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Sample records for regenerative hyperplasia nrh

  1. Hepatic Lesions Caused by Large Granular Lymphocyte Leukemia in Fischer 344 Rats: Similar Morphologic Features and Morphogenesis to Those of Nodular Regenerative Hyperplasia (NRH) in the Human Liver.

    PubMed

    Shiga, Atsushi; Narama, Isao

    2015-08-01

    To characterize the hepatic lesions in Fischer 344 (F344) rats afflicted with large granular lymphocyte (LGL) leukemia, the livers of rats with LGL leukemia at various stages were examined histopathologically and immunohistochemically. The morphologic features in the livers of rats afflicted with LGL leukemia were diffuse, uniform-sized, granular, or micronodular lesions consisting of hepatocytes showing centrilobular atrophy and perilobular hypertrophy (CAPH) without fibrosis. With progression in the stage of the LGL leukemia, the severity of the CAPH of hepatocytes increased resulting in fatty change and/or single-cell necrosis, along with compensatory hyperplasia of the hepatocytes, finally resulting in lesions similar to those seen in nodular regenerative hyperplasia (NRH) in the human liver. The CAPH of hepatocytes was a nonspecific tissue adaptation against ischemia or hypoxemia and/or imbalance in blood supply due to disturbance in the portal circulation and hemolytic anemia induced by the leukemia cells. In addition, direct and/or indirect hepatocellular injuries by leukemia cells were considered to be necessary for the formation of human NRH-like lesions. Morphogenetic investigation of the livers of rats afflicted with LGL leukemia may be helpful to clarify the pathogenesis of NRH in the human liver.

  2. [Nodular regenerative hyperplasia as a complication of thiopurine treatment in a patient with inflammatory bowel disease].

    PubMed

    Cohen-Ezra, Oranit; Avni, Yona; Morgenstern, Sara; Ben-Ari, Ziv

    2012-12-01

    Immunomodulator therapy with thiopurine analogues azathioprine or 6-mercaptopurine is commonly prescribed for the treatment of organ transplantation, inflammatory bowel disease, autoimmune diseases and malignancies. Hepatotoxicity due to thiopurine analogues usually presents as an increase in serum transaminase levels. Toxicity is usually not severe, and a dose reduction is effective in most patients. Nodular regenerative hyperplasia (NRH) is a very rare but potentially severe complication of thiopurine-containing therapy. NRH is often asymptomatic, neither biochemical nor molecular markers are indicative for NRH. The suspicion rises when there are clinical symptoms of portal hypertension or increases in transaminases levels orthrombocytopenia. Liver biopsy is essential for definitive diagnosis. This is a case report of a 40-year-old male patient with Crohn's disease who developed increased serum levels of liver enzymes and thrombocytopenia following the administration of thiopurine. Although treatment with thiopurine was discontinued, he has further progressed and presented with acute variceal bleeding due to portal hypertension. The diagnosis of nodular regenerative hyperplasia was proven by a liver biopsy. In conclusion, NRH is a very rare but potentially severe complication of thiopurine-containing immunosuppressive therapy for IBD.

  3. [Regenerative nodular hyperplasia in HIV].

    PubMed

    González, Ramiro Javier Romo; Chaves, Emiliano; Mullen, Eduardo; Copello, Hercilia

    2011-12-01

    Nodular regenerative hyperplasia of the liver is a rare condition. We describe here the case of a patient with HIV who presented with a clinical syndrome of portal hypertension. After multiple evaluations the diagnosis was recognized by the histology. The findings were attributed to the prolonged use of didanosine.

  4. A case of idiopathic portal hypertension associated with nodular regenerative hyperplasia-like nodule of the liver and mixed connective tissue disease.

    PubMed

    Hayano, Shunsuke; Naganuma, Atsushi; Okano, Yudai; Suzuki, Yuhei; Shiina, Keisuke; Yoshida, Haruka; Hayashi, Eri; Uehara, Sanae; Hoshino, Takashi; Miyamae, Naomi; Kudo, Tomohiro; Ishihara, Hiroshi; Ogawa, Akira; Sato, Ken; Kakizaki, Satoru

    2016-05-01

    A 51-year-old woman was diagnosed with mixed connective tissue disease (MCTD) in 2011. She underwent treatment with prednisolone. Her hepatobiliary enzyme level increased, and multiple nodules were found in both liver lobes in abdominal imaging studies. Ultrasonography revealed large and small hyperechoic lesions with indistinct or well-defined borders. No findings of classic hepatocellular carcinoma or liver cirrhosis were observed on contrast-enhanced computed tomography, but some nodules showed an enhanced effect of the central lesion that was characteristic of focal nodular hyperplasia (FNH) in an arterial phase. On gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging, slightly high-intensity nodules, 10-40mm in size, were observed on T1- and T2-weighted images. The nodules showed highest intensities in the hepatocyte phase and were enhanced with the uptake of Gd-EOB-DTPA as compared with the background liver. FNH was suspected based on the imaging findings, but we performed a liver tumor biopsy for differential diagnosis of the malignant lesion. Based on the immunohistopathological examination results, the final diagnosis was idiopathic portal hypertension associated with nodular regenerative hyperplasia (NRH)-like nodule of the liver. Benign nodular hepatocellular lesions are caused by abnormal hepatic circulation and were previously known as anomalous portal tract syndrome. Our case of atypical NRH with large nodules may be included in this disease entity. Here, we report a rare case of MCTD with NRH-like nodules and idiopathic portal hypertension with a review of literature.

  5. Diffuse Muscular Pain, Skin Tightening, and Nodular Regenerative Hyperplasia Revealing Paraneoplastic Amyopathic Dermatomyositis due to Testicular Cancer.

    PubMed

    Norrenberg, Sarah; Gangji, Valérie; Del Marmol, Véronique; Soyfoo, Muhammad S

    2012-01-01

    Paraneoplastic dermatomyositis (DM) associated with testicular cancer is extremely rare. We report the case of a patient with skin tightening, polymyalgia, hypereosinophilia, and nodular regenerative hyperplasia revealing seminoma and associated paraneoplastic DM.

  6. Concurrent liver hodgkin lymphoma and nodular regenerative hyperplasia on an explanted liver with clinical diagnosis of alcoholic cirrhosis at university hospital fundación santa fe de bogotá.

    PubMed

    López, R; Barrera, L; Vera, A; Andrade, R

    2014-01-01

    Liver involvement by Hodgkin lymphoma (HL) is well documented. However, secondary liver failure to this neoplastic process is rare and usually presents late in the course of the disease. We present a case of a HL associated with nodular regenerative hyperplasia (NRH) diagnosed on an explanted liver from a 53-year-old patient with clinical diagnosis of alcoholic cirrhosis. Hematoxylin and eosin stain (H&E) showed abnormal liver architecture with hepatocytes nodules highlighted by reticulin stain with absent fibrosis on the trichrome stain. The portal spaces had diffuse infiltration by Reed-Sternberg cells positive for CD15, CD30, and latent membrane protein (LMP) on immunohistochemical studies. The patient also had a concurrent hilar lymph node biopsy that also showed HL involvement. Liver failure as the initial presentation of Hodgkin' lymphoma is rare. We believe that more research about the utility of performing liver biopsies in patients candidates for transplantation with noncirrhotic hepatic failure is needed in order to establish the etiology and the optimal treatment.

  7. Parathyroid hyperplasia

    MedlinePlus

    Enlarged parathyroid glands; Osteoporosis - parathyroid hyperplasia; Bone thinning - parathyroid hyperplasia; Osteopenia - parathyroid hyperplasia; High calcium level - parathyroid hyperplasia; Chronic kidney disease - parathyroid hyperplasia; ...

  8. Pregnancy restores the regenerative capacity of the aged liver via activation of an mTORC1-controlled hyperplasia/hypertrophy switch.

    PubMed

    Gielchinsky, Yuval; Laufer, Neri; Weitman, Efi; Abramovitch, Rinat; Granot, Zvi; Bergman, Yehudit; Pikarsky, Eli

    2010-03-15

    Regenerative capacity is progressively lost with age. Here we show that pregnancy markedly improved liver regeneration in aged mice concomitantly with inducing a switch from proliferation-based liver regeneration to a regenerative process mediated by cell growth. We found that the key mediator of this switch was the Akt/mTORC1 pathway; its inhibition blocked hypertrophy, while increasing proliferation. Moreover, pharmacological activation of this pathway sufficed to induce the hypertrophy module, mimicking pregnancy. This treatment dramatically improved hepatic regenerative capacity and survival of old mice. Thus, cell growth-mediated mass reconstitution, which is relatively resistant to the detrimental effects of aging, is employed in a physiological situation and holds potential as a therapeutic strategy for ameliorating age-related functional deterioration.

  9. High resolution observations with Artemis-IV and the NRH. I. Type IV associated narrow-band bursts

    NASA Astrophysics Data System (ADS)

    Bouratzis, C.; Hillaris, A.; Alissandrakis, C. E.; Preka-Papadema, P.; Moussas, X.; Caroubalos, C.; Tsitsipis, P.; Kontogeorgos, A.

    2016-02-01

    Context. Narrow-band bursts appear on dynamic spectra from microwave to decametric frequencies as fine structures with very small duration and bandwidth. They are believed to be manifestations of small scale energy release through magnetic reconnection. Aims: We analyzed 27 metric type IV events with embedded narrow-band bursts, which were observed by the ARTEMIS-IV radio spectrograph from 30 June 1999 to 1 August 2010. We examined the morphological characteristics of isolated narrow-band structures (mostly spikes) and groups or chains of structures. Methods: The events were recorded with the SAO high resolution (10 ms cadence) receiver of ARTEMIS-IV in the 270-450 MHz range. We measured the duration, spectral width, and frequency drift of ~12 000 individual narrow-band bursts, groups, and chains. Spike sources were imaged with the Nançay radioheliograph (NRH) for the event of 21 April 2003. Results: The mean duration of individual bursts at fixed frequency was ~100 ms, while the instantaneous relative bandwidth was ~2%. Some bursts had measurable frequency drift, either positive or negative. Quite often spikes appeared in chains, which were closely spaced in time (column chains) or in frequency (row chains). Column chains had frequency drifts similar to type-IIId bursts, while most of the row chains exhibited negative frequently drifts with a rate close to that of fiber bursts. From the analysis of NRH data, we found that spikes were superimposed on a larger, slowly varying, background component. They were polarized in the same sense as the background source, with a slightly higher degree of polarization of ~65%, and their size was about 60% of their size in total intensity. Conclusions: The duration and bandwidth distributions did not show any clear separation in groups. Some chains tended to assume the form of zebra, lace stripes, fiber bursts, or bursts of the type-III family, suggesting that such bursts might be resolved in spikes when viewed with high

  10. Endometrial hyperplasia.

    PubMed

    Mills, Anne M; Longacre, Teri A

    2010-11-01

    Endometrial hyperplasia is a heterogeneous set of pathologic lesions that range from mild, reversible glandular proliferations to direct cancer precursors. These lesions comprise a continuum of morphologic appearances, with the earliest proliferation represented by crowded glands with simple tubular architecture lined by cells resembling proliferative endometrium, whereas advanced proliferations in this continuum are characterized by crowded glands with complex architecture, often containing cells with nuclear atypia resembling low-grade endometrioid adenocarcinoma. The former "early" proliferations may be isolated to an endometrial polyp, but advanced proliferations are generally more diffusely present throughout the endometrium. There are at least three major classification systems for endometrial carcinoma precursor lesions, each of which trend toward overlap at the complex end of the spectrum. Although some classifications are based on a series of molecular genetic alterations (which may or may not translate into biologically or clinically relevant risk lesions), each classification scheme ultimately uses a series of histologic features, usually a combination of architecture and cytology, to establish a diagnosis of hyperplasia. Because different pathologists may apply different histologic criteria for endometrial hyperplasia depending on the classification system used, this article will provide an overview of the classifications used in current daily practice, present the histologic criteria and relative merits of each classification system, and discuss common and not so common causes of misclassification.

  11. The two common polymorphic forms of human NRH-quinone oxidoreductase 2 (NQO2) have different biochemical properties.

    PubMed

    Megarity, Clare F; Gill, James R E; Caraher, M Clare; Stratford, Ian J; Nolan, Karen A; Timson, David J

    2014-05-02

    There are two common forms of NRH-quinone oxidoreductase 2 (NQO2) in the human population resulting from SNP rs1143684. One has phenylalanine at position 47 (NQO2-F47) and the other leucine (NQO2-L47). Using recombinant proteins, we show that these variants have similar steady state kinetic parameters, although NQO2-L47 has a slightly lower specificity constant. NQO2-L47 is less stable towards proteolytic digestion and thermal denaturation than NQO2-F47. Both forms are inhibited by resveratrol, but NQO2-F47 shows negative cooperativity with this inhibitor. Thus these data demonstrate, for the first time, clear biochemical differences between the variants which help explain previous biomedical and epidemiological findings.

  12. Hyperplasia (Ductal or Lobular)

    MedlinePlus

    ... is also known as epithelial hyperplasia or proliferative breast disease. It’s an overgrowth of the cells that line the ducts or the milk glands (lobules). Hyperplasia may be called either ductal hyperplasia ( ...

  13. Regenerative Aerobraking

    NASA Technical Reports Server (NTRS)

    Moses, Robert W.

    2004-01-01

    NASA's exploration goals for Mars and Beyond will require new power systems and in situ resource utilization technologies. Regenerative aerobraking may offer a revolutionary approach for in situ power generation and oxygen harvesting during these exploration missions. In theory, power and oxygen can be collected during aerobraking and stored for later use in orbit or on the planet. This technology would capture energy and oxygen from the plasma field that occurs naturally during hypersonic entry using well understood principles of magnetohydrodynamics and oxygen filtration. This innovative approach generates resources upon arrival at the operational site, and thus greatly differs from the traditional approach of taking everything you need with you from Earth. Fundamental analysis, computational fluid dynamics, and some testing of experimental hardware have established the basic feasibility of generating power during a Mars entry. Oxygen filtration at conditions consistent with spacecraft entry parameters at Mars has been studied to a lesser extent. Other uses of the MHD power are presented. This paper illustrates how some features of regenerative aerobraking may be applied to support human and robotic missions at Mars.

  14. Regenerative Aerobraking

    NASA Astrophysics Data System (ADS)

    Moses, Robert W.

    2005-02-01

    NASA's exploration goals for Mars and Beyond will require new power systems and in situ resource utilization technologies. Regenerative aerobraking may offer a revolutionary approach for in situ power generation and oxygen harvesting during these exploration missions. In theory, power and oxygen can be collected during aerobraking and stored for later use in orbit or on the planet. This technology would capture energy and oxygen from the plasma field that occurs naturally during hypersonic entry using well understood principles of magnetohydrodynamics and oxygen filtration. This innovative approach generates resources upon arrival at the operational site, and thus greatly differs from the traditional approach of taking everything you need with you from Earth. Fundamental analysis, computational fluid dynamics, and some testing of experimental hardware have established the basic feasibility of generating power during a Mars entry. Oxygen filtration at conditions consistent with spacecraft entry parameters at Mars has been studied to a lesser extent. Other uses of the MHD power are presented. This paper illustrates how some features of regenerative aerobraking may be applied to support human and robotic missions at Mars.

  15. Fully relayed regenerative amplifier

    DOEpatents

    Glass, Alexander J.

    1981-01-01

    A regenerative laser apparatus and method using the optical relay concept to maintain high fill factors, to suppress diffraction effects, and to minimize phase distortions in a regenerative amplifier.

  16. [Regenerative approach for COPD].

    PubMed

    Kubo, Hiroshi

    2011-10-01

    No treatment to cure of chronic obstructive pulmonary disease (COPD) is available. Regenerative medicine is one of promising areas for this intractable disease. Several reagents and growth factors are known to promote lung regeneration in small animal models. However, regenerative medicines for human lungs are not achieved yet. Recent advances in stem cell biology and tissue engineering have expanded our understanding of lung endogenous stem cells, and this new knowledge provides us with new ideas for future regenerative therapy for lung diseases. Although lungs are the most challenging organ for regenerative medicine, our cumulative knowledge of lung regeneration and of endogenous progenitor cells makes clear the possibilities for regenerative approach to COPD.

  17. Benign prostate hyperplasia (BPH) - resources

    MedlinePlus

    Resources - benign prostatic hyperplasia (BPH); Prostate enlargement resources; BPH resources ... organizations provide information on benign prostatic hyperplasia ( prostate enlargement ): National Kidney and Urologic Diseases Information Clearinghouse -- www. ...

  18. NRH Neuroscience Research Center

    DTIC Science & Technology

    2004-06-01

    platelet medications (Persantine, Dipyridamole, Ticlodipine, Plavix, Clopidogril, Aspirin, Aggrenox) and anticoagulants (Heparin, Coumadin, Warfarin...supplement list to determine which items should ’count’ as supplements. Snacks and bowel agents such as yogurt and fiber rich should not count as dietary...Levodopa, Carbidura, Bromocriptine Cholinergics: Aricept, Reminyl, Cognex, Exelon, Tacrine, Antiplatelet , Aspirin, Persantine, Aggrenox, Plavix, Ticlid

  19. NRH Neuroscience Research Center

    DTIC Science & Technology

    2008-06-01

    Project E3: Neuropsychology Conference The Principal Investigator (Dr. Garmoe) attended fMRI workshops at the National Academy of Neuropsychology...annual conference in 2003. In addition, he met with Dr. Frank Hillary, an experienced fMRI researcher (who at the time was at Kessler), to discuss...feasibility of fMRI designs. Dr. Hillary affirmed the feasibility of fMRI protocols to investigate self-awareness, and possible collaboration was

  20. NRH Neuroscience Research Center

    DTIC Science & Technology

    2005-06-01

    substance in question or a nonactive placebo sugar of psychoanalysis . Surgeons struggle with creating pill. The whole patient experience is rigorously...placebo sugar of psychoanalysis . Surgeons struggle with creating pill. The whole patient experience is rigorously sham interventions,41" and a lot of

  1. Regenerative (Regen) ECLSS Operations Water Balance

    NASA Technical Reports Server (NTRS)

    Tobias, Barry

    2010-01-01

    In November 2008, the Water Regenerative System racks were launched aboard Space Shuttle flight, STS-126 (ULF2) and installed and activated on the International Space Station (ISS). These racks, consisting of the Water Processor Assembly (WPA) and Urine Processor Assembly (UPA), completed the installation of the Regenerative (Regen) ECLSS systems which includes the Oxygen Generator Assembly (OGA) that was launched 2 years prior. With the onset of active water management on the US segment of the ISS, a new operational concept was required, that of "water balance." Even more recently, in 2010 the Sabatier system came online which converts H2 and CO2 into water and methane. The Regen ECLSS systems accept condensation from the atmosphere, urine from crew, and processes that fluid via various means into potable water which is used for crew drinking, building up skip-cycle water inventory, and water for electrolysis to produce oxygen. Specification rates of crew urine output, condensate output, O2 requirements, toilet flush water and drinking needs are well documented and used as a general plan when Regen ECLSS came online. Spec rates are useful in long term planning, however, daily or weekly rates are dependent on a number of variables. The constantly changing rates created a new challenge for the ECLSS flight controllers, who are responsible for operating the ECLSS systems onboard ISS. This paper will review the various inputs to rate changes and inputs to planning events, including but not limited to; crew personnel makeup, Regen ECLSS system operability, vehicle traffic, water containment availability, and Carbon Dioxide Removal Assembly (CDRA) capability. Along with the inputs that change the various rates, the paper will review the different systems, their constraints and finally the operational means by which flight controllers manage this new challenge of "water balance."

  2. Regenerative medicine blueprint.

    PubMed

    Terzic, Andre; Harper, C Michel; Gores, Gregory J; Pfenning, Michael A

    2013-12-01

    Regenerative medicine, a paragon of future healthcare, holds unprecedented potential in extending the reach of treatment modalities for individuals across diseases and lifespan. Emerging regenerative technologies, focused on structural repair and functional restoration, signal a radical transformation in medical and surgical practice. Regenerative medicine is poised to provide innovative solutions in addressing major unmet needs for patients, ranging from congenital disease and trauma to degenerative conditions. Realization of the regenerative model of care predicates a stringent interdisciplinary paradigm that will drive validated science into standardized clinical options. Designed as a catalyst in advancing rigorous new knowledge on disease causes and cures into informed delivery of quality care, the Mayo Clinic regenerative medicine blueprint offers a patient-centered, team-based strategy that optimizes the discovery-translation-application roadmap for the express purpose of science-supported practice advancement.

  3. Regenerative Hydride Heat Pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    1992-01-01

    Hydride heat pump features regenerative heating and single circulation loop. Counterflow heat exchangers accommodate different temperatures of FeTi and LaNi4.7Al0.3 subloops. Heating scheme increases efficiency.

  4. INCIDENCE OF ENDOMETRIAL HYPERPLASIA

    PubMed Central

    REED, Susan D.; NEWTON, Katherine M.; CLINTON, Walter L.; EPPLEIN, Meira; GARCIA, Rochelle; ALLISON, Kimberly; VOIGT, Lynda F.; Weiss, Noel S.

    2009-01-01

    Objective Estimate age-specific incidence of endometrial hyperplasia: simple, complex, and atypical, in order of increasing likelihood of progression to carcinoma. Study design Women ages 18–90 years with endometrial pathology specimens (1985–2003) at a large integrated health plan were identified using automated data. Incidence rates were obtained by dividing the number of cases by the estimated number of female health plan enrollees who retained a uterus. Results Endometrial hyperplasia peak incidence was: simple-142/100,000 woman-years, complex-213/100,000 woman-years, both in the early 50s; and atypical-56/100,000 woman-years in the early 60s. Age-adjusted incidence decreased over the study period, especially for atypical hyperplasia. Conclusions Endometrial hyperplasia incidence without and with atypia peaks in the early postmenopausal years and in the early 60s, respectively. Given that some cases of endometrial hyperplasia likely go undiagnosed, the figures provided should be viewed as minimum estimates of the true incidence. PMID:19393600

  5. [Focal epithelial hyperplasia].

    PubMed

    Vera-Iglesias, E; García-Arpa, M; Sánchez-Caminero, P; Romero-Aguilera, G; Cortina de la Calle, P

    2007-11-01

    Focal epithelial hyperplasia is a rare disease of the oral mucosa caused by the human papilloma virus (HPV). It appears as a benign epithelial growth, usually in the mucosa of the lower lip. It is mainly associated with HPV serotypes 13 and 32 and there is a clear racial predilection for the disease in Native Americans and Eskimos. We describe the case of a 17-year-old girl from Ecuador with multiple papular lesions in both lips that were clinically and histologically consistent with focal epithelial hyperplasia. Analysis by polymerase chain reaction detected HPV serotype 13.

  6. Congenital Adrenal Hyperplasia

    PubMed Central

    Speiser, Phyllis W.

    2015-01-01

    Congenital adrenal hyperplasia associated with deficiency of steroid 21-hydroxylase is the most common inborn error in adrenal function and the most common cause of adrenal insufficiency in the pediatric age group. As patients now survive into adulthood, adult health-care providers must also be familiar with this condition. Over the past several years, F1000 has published numerous commentaries updating research and practical guidelines for this condition. The purposes of this review are to summarize basic information defining congenital adrenal hyperplasia and to highlight current knowledge and controversies in management. PMID:26339484

  7. Regenerative Life Support Evaluation

    NASA Technical Reports Server (NTRS)

    Kleiner, G. N.; Thompson, C. D.

    1977-01-01

    This paper describes the development plan and design concept of the Regenerative Life Support Evaluation (RLSE) planned for flight testing in the European Space Agency Spacelab. The development plan encompasses the ongoing advanced life support subsystem and a systems integration effort to evolve concurrently subsystem concepts that perform their function and can be integrated with other subsystems in a flight demonstration of a regenerative life support system. The design concept for RLSE comprises water-electrolysis O2 generation, electrochemically depolarized CO2 removal, and Sabatier CO2 reduction for atmosphere regeneration, urine vapor-compression distillation, and wash-water hyperfiltration for waste-water recovery. The flight demonstration by RLSE is an important step in qualifying the regenerative concepts for life support in space stations.

  8. Regenerative similariton laser

    NASA Astrophysics Data System (ADS)

    North, Thibault; Brès, Camille-Sophie

    2016-05-01

    Self-pulsating lasers based on cascaded reshaping and reamplification (2R) are capable of initiating ultrashort pulses despite the accumulation of large amounts of nonlinearities in all-fiber resonators. The spectral properties of pulses in self-similar propagation are compatible with cascaded 2R regeneration by offset filtering, making parabolic pulses suitable for the design of a laser of this recently introduced class. A new type of regenerative laser giving birth to similaritons is numerically investigated and shows that this laser is the analog of regenerative sources based solely on self-phase modulation and offset filtering. The regenerative similariton laser does not suffer from instabilities due to excessive nonlinearities and enables ultrashort pulse generation in a simple cavity configuration.

  9. Oral focal epithelial hyperplasia.

    PubMed

    Bassioukas, K; Danielides, V; Georgiou, I; Photos, E; Zagorianakou, P; Skevas, A

    2000-01-01

    Focal epithelial hyperplasia (FEH) or Heck disease, is a rare viral infection of the oral mucosa caused by HPV 13 or HPV 32. In Caucasians there have been only a few cases reported. We present the first case in Greece in a young Caucasian girl in which HPV 13 was detected with PCR analysis. The patient was successfully treated with CO2 laser.

  10. Congenital adrenal hyperplasia

    MedlinePlus

    ... or inappropriately). Congenital adrenal hyperplasia can affect both boys and girls. About 1 in 10,000 to 18,000 ... penis but normal testes Well-developed muscles Both boys and girls will be tall as children, but much shorter ...

  11. Microscale Regenerative Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Moran, Matthew E.; Stelter, Stephan; Stelter, Manfred

    2006-01-01

    The device described herein is designed primarily for use as a regenerative heat exchanger in a miniature Stirling engine or Stirling-cycle heat pump. A regenerative heat exchanger (sometimes called, simply, a "regenerator" in the Stirling-engine art) is basically a thermal capacitor: Its role in the Stirling cycle is to alternately accept heat from, then deliver heat to, an oscillating flow of a working fluid between compression and expansion volumes, without introducing an excessive pressure drop. These volumes are at different temperatures, and conduction of heat between these volumes is undesirable because it reduces the energy-conversion efficiency of the Stirling cycle.

  12. Oral focal epithelial hyperplasia.

    PubMed

    López-Jornet, Pía; Camacho-Alonso, Fabio; Berdugo, Lucero

    2010-01-01

    Focal epithelial hyperplasia (FEH) is a benign, asymptomatic disease. It appears as papules, principally on the lower lip, although it can also be found on the retro-commissural mucosa and tongue and, less frequently, on the upper lip, gingiva and palate. FEH is caused by human papillomavirus subtype 13 or 32. The condition occurs in many populations and ethnic groups. We present the clinical case of a 31-year-old male with lesions that clinically and histologically corresponded to FEH.

  13. Regenerative periodontal therapy.

    PubMed

    Hägi, Tobias T; Laugisch, Oliver; Ivanovic, Aleksandar; Sculean, Anton

    2014-03-01

    The goal of regenerative periodontal therapy is to completely restore the tooth's supporting apparatus that has been lost due to inflammatory periodontal disease or injury. It is characterized by formation of new cementum with inserting collagen fibers, new periodontal ligament, and new alveolar bone. Indeed conventional, nonsurgical, and surgical periodontal therapy usually result in clinical improvements evidenced by probing depth reduction and clinical attachment gain, but the healing occurs predominantly through formation of a long junctional epithelium and no or only unpredictable periodontal regeneration. Therefore, there is an ongoing search for new materials and improved surgical techniques, with the aim of predictably promoting periodontal wound healing/regeneration and improving the clinical outcome. This article attempts to provide the clinician with an overview of the most important biologic events involved in periodontal wound healing/ regeneration and on the criteria on how to select the appropriate regenerative material and surgical technique in order to optimize the clinical outcomes.

  14. Regenerative photonic therapy: Review

    NASA Astrophysics Data System (ADS)

    Salansky, Natasha; Salansky, Norman

    2012-09-01

    After four decades of research of photobiomodulation phenomena in mammals in vitro and in vivo, a solid foundation is created for the use of photobiomodulation in regenerative medicine. Significant accomplishments are achieved in animal models that demonstrate opportunities for photo-regeneration of injured or pathological tissues: skin, muscles and nerves. However, the use of photobiomodulation in clinical studies leads to controversial results while negative or marginal clinical efficacy is reported along with positive findings. A thor ough analysis of requirements to the optical parameters (dosimetry) for high efficacy in photobimodulation led us to the conclusion that there are several misconceptions in the clinical applications of low level laser therapy (LLLT). We present a novel appr oach of regenerative photonic therapy (RPT) for tissue healing and regeneration that overcomes major drawbacks of LLLT. Encouraging clinical results on RPT efficacy are presented. Requirements for RPT approach and vision for its future development for tissue regeneration is discussed.

  15. Regenerative fuel cells

    NASA Technical Reports Server (NTRS)

    Swette, Larry L.; Kackley, Nancy D.; Laconti, Anthony B.

    1992-01-01

    A development status evaluation is presented for moderate-temperature, single-unit, regenerative fuel cells using either alkaline or solid polymer proton-exchange membrane (PEM) electrolytes. Attention is given to the results thus far obtained for Pt, Ir, Rh, and Na(x)Pt3O4 catalysts. Alkaline electrolyte tests have been performed on a half-cell basis with a floating-electrode cell; PEM testing has been with complete fuel cells, using Nafion 117.

  16. Regenerative fuel cells

    NASA Astrophysics Data System (ADS)

    Swette, Larry L.; Kackley, Nancy D.; Laconti, Anthony B.

    A development status evaluation is presented for moderate-temperature, single-unit, regenerative fuel cells using either alkaline or solid polymer proton-exchange membrane (PEM) electrolytes. Attention is given to the results thus far obtained for Pt, Ir, Rh, and Na(x)Pt3O4 catalysts. Alkaline electrolyte tests have been performed on a half-cell basis with a floating-electrode cell; PEM testing has been with complete fuel cells, using Nafion 117.

  17. Regenerative feedback resonant circuit

    DOEpatents

    Jones, A. Mark; Kelly, James F.; McCloy, John S.; McMakin, Douglas L.

    2014-09-02

    A regenerative feedback resonant circuit for measuring a transient response in a loop is disclosed. The circuit includes an amplifier for generating a signal in the loop. The circuit further includes a resonator having a resonant cavity and a material located within the cavity. The signal sent into the resonator produces a resonant frequency. A variation of the resonant frequency due to perturbations in electromagnetic properties of the material is measured.

  18. Cytomics in regenerative medicine

    NASA Astrophysics Data System (ADS)

    Tárnok, Attila; Pierzchalski, Arkadiusz

    2008-02-01

    Cytomics is the high-content analysis of cell-systems [6, 78]. The area of Cytomics and Systems Biology received great attention during the last years as it harbours the promise to substantially impact on various fields of biomedicine, drug discovery, predictive medicine [6] and may have major potential for regenerative medicine. In regenerative medicine Cytomics includes process control of cell preparation and culturing using non-invasive detection techniques, quality control and standardization for GMP and GLP conformity and even prediction of cell fate based on sophisticated data analysis. Cytomics requires quantitative and stoichiometric single cell analysis. In some areas the leading cytometric techniques represent the cutting edge today. Many different applications/variations of multicolour staining were developed for flow- or slide-based cytometry (SBC) analysis of suspensions and sections to whole animal analysis [78]. SBC has become an important analytical technology in drug discovery, diagnosis and research and is an emerging technology for systems analysis [78]. It enables high-content high-throughput measurement of cell suspensions, cell cultures and tissues. In the last years various commercial SBC instruments were launched principally enabling to perform similar tasks. Standardisation as well as comparability of different instruments is a major challenge. Hyperspectral optical imaging may be implemented in SBC analysis for label free cell detection based on cellular autofluorescence [3]. All of these developments push the systemic approach of the analysis of biological specimens to enhance the outcome of regenerative medicine.

  19. [Focal epithelial hyperplasia].

    PubMed

    Delgado, Yolanda; Torrelo, Antonio; Colmenero, Isabel; Zambrano, Antonio

    2005-12-01

    Focal epithelial hyperplasia (FEH) is a benign proliferation of the oral mucosa with well defined clinical and histological characteristics. It has been associated with infection of the oral mucosa by types 13 and 32 of the human papillomavirus (HPV), and to a lesser extent, with other types. Its clinical course is variable, although it usually persists for months or years; cases with spontaneous resolution have been described, as have others with prolonged persistence. We present the case of an Ecuadorian boy whose visit was motivated by lesions in the oral mucosa consistent with a diagnosis of FEH, which were confirmed in the histological study, and in which HPV type 13 DNA was identified.

  20. Oncocytic hyperplasia of the larynx.

    PubMed

    Thawley, S E; Berlin, B P; Berkowitz, W P

    1977-07-01

    Oncocytic hyperplasia of the larynx is rare. The lesion most commonly arises from the false vocal chord. A distinction arises between oncocytomas of the salivary glands which are considered to be neoplasms and extrasalivary oncocytic lesions which are secondary to hyperplasia. Oncocytic lesions of the larynx are benign and treatment is excision. They may be multiple, but recurrences are rare.

  1. REGENERATIVE TRANSISTOR AMPLIFIER

    DOEpatents

    Kabell, L.J.

    1958-11-25

    Electrical circults for use in computers and the like are described. particularly a regenerative bistable transistor amplifler which is iurned on by a clock signal when an information signal permits and is turned off by the clock signal. The amplifier porforms the above function with reduced power requirements for the clock signal and circuit operation. The power requirements are reduced in one way by employing transformer coupling which increases the collector circuit efficiency by eliminating the loss of power in the collector load resistor.

  2. Regenerative adsorbent heat pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor)

    1991-01-01

    A regenerative adsorbent heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system and at least a portion of the heat of adsorption. A series of at least four compressors containing an adsorbent is provided. A large amount of heat is transferred from compressor to compressor so that heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

  3. Regenerative Sorption Refrigerator

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.; Wen, Liang-Chi; Bard, Steven

    1991-01-01

    Two-stage sorption refrigerator achieves increased efficiency via regenerative-heating concept in which waste heat from praseodymium/cerium oxide (PCO) chemisorption compressor runs charcoal/krypton (C/Kr) sorption compressor. Waste heat from each PCO sorption compressor used to power surrounding C/Kr sorption compressor. Flows of heat in two compressor modules controlled by gas-gap thermal switches. Has no wearing moving parts other than extremely long life, room-temperature check valves operating about twice per hour. Virtually no measurable vibration, and has potential operating life of at least ten years.

  4. Regenerative air heater

    DOEpatents

    Hasselquist, P.B.; Baldner, R.

    1980-11-26

    A gas-cooled steel skirt is used to support a refractory cored brick matrix and dome structure in a high temperature regenerative air heater useful in magnetohydrodynamic power generation. The steel skirt thermally expands to accommodate the thermal expansion of the dome structure despite substantial temperature differential thereby reducing relative movement between the dome bricks. Gas cooling of the steel skirt allows the structure to operate above its normal temperature during clean-out cycles and also allows for the control of the thermal expansion of the steel skirt.

  5. Regenerative air heater

    DOEpatents

    Hasselquist, Paul B.; Baldner, Richard

    1982-01-01

    A gas-cooled steel skirt is used to support a refractory cored brick matrix and dome structure in a high temperature regenerative air heater useful in magnetohydrodynamic power generation. The steel skirt thermally expands to accommodate the thermal expansion of the dome structure despite substantial temperature differential thereby reducing relative movement between the dome bricks. Gas cooling of the steel skirt allows the structure to operate above its normal temperature during clean-out cycles and also allows for the control of the thermal expansion of the steel skirt.

  6. Regenerative Medicine Build-Out

    PubMed Central

    Pfenning, Michael A.; Gores, Gregory J.; Harper, C. Michel

    2015-01-01

    Summary Regenerative technologies strive to boost innate repair processes and restitute normative impact. Deployment of regenerative principles into practice is poised to usher in a new era in health care, driving radical innovation in patient management to address the needs of an aging population challenged by escalating chronic diseases. There is urgency to design, execute, and validate viable paradigms for translating and implementing the science of regenerative medicine into tangible health benefits that provide value to stakeholders. A regenerative medicine model of care would entail scalable production and standardized application of clinical grade biotherapies supported by comprehensive supply chain capabilities that integrate sourcing and manufacturing with care delivery. Mayo Clinic has rolled out a blueprint for discovery, translation, and application of regenerative medicine therapies for accelerated adoption into the standard of care. To establish regenerative medical and surgical service lines, the Mayo Clinic model incorporates patient access, enabling platforms and delivery. Access is coordinated through a designated portal, the Regenerative Medicine Consult Service, serving to facilitate patient/provider education, procurement of biomaterials, referral to specialty services, and/or regenerative interventions, often in clinical trials. Platforms include the Regenerative Medicine Biotrust and Good Manufacturing Practice facilities for manufacture of clinical grade products for cell-based, acellular, and/or biomaterial applications. Care delivery leverages dedicated interventional suites for provision of regenerative services. Performance is tracked using a scorecard system to inform decision making. The Mayo Clinic roadmap exemplifies an integrated organization in the discovery, development, and delivery of regenerative medicine within a growing community of practice at the core of modern health care. Significance Regenerative medicine is at the

  7. Will Regenerative Medicine Replace Transplantation?

    PubMed Central

    Orlando, Giuseppe; Soker, Shay; Stratta, Robert J.; Atala, Anthony

    2013-01-01

    Recent groundbreaking advances in organ bioengineering and regeneration have provided evidence that regenerative medicine holds promise to dramatically improve the approach to organ transplantation. The two fields, however, share a common heritage. Alexis Carrel can be considered the father of both regenerative medicine and organ transplantation, and it is now clear that his legacy is equally applicable for the present and future generations of transplant and regenerative medicine investigators. In this review, we will briefly illustrate the interplay that should be established between these two complementary disciplines of health sciences. Although regenerative medicine has shown to the transplant field its potential, transplantation is destined to align with regenerative medicine and foster further progress probably more than either discipline alone. Organ bioengineering and regeneration technologies hold the promise to meet at the same time the two most urgent needs in organ transplantation, namely, the identification of a new, potentially inexhaustible source of organs and immunosuppression-free transplantation of tissues and organs. PMID:23906883

  8. Extensive focal epithelial hyperplasia.

    PubMed

    Hashemipour, Maryam Alsadat; Shoryabi, Ali; Adhami, Shahrzad; Mehrabizadeh Honarmand, Hoda

    2010-01-01

    Heck's disease or focal epithelial hyperplasia is a benign contagious disease caused by human papillomavirus types 13 or 32. It occurs with low frequency in the Iranian population. This condition is characterized by the occurrence of multiple, small papules or nodules in the oral cavity, especially on the labial and buccal mucosa and tongue. In some populations, up to 39% of children are affected. Conservative surgical excision of lesions may be performed for diagnostic or aesthetic purposes. The risk of recurrence after this therapy is minimal, and there seems to be no malignant transformation potential. In the present work, we presented the clinical case of a 12-year-old Iranian girl with oral lesions that clinically and histologically correspond to Heck's disease.

  9. Congenital adrenal hyperplasia.

    PubMed

    Merke, Deborah P; Bornstein, Stefan R

    Congenital adrenal hyperplasia (CAH) due to deficiency of 21-hydroxylase is a disorder of the adrenal cortex characterised by cortisol deficiency, with or without aldosterone deficiency, and androgen excess. Patients with the most severe form also have abnormalities of the adrenal medulla and epinephrine deficiency. The severe classic form occurs in one in 15,000 births worldwide, and the mild non-classic form is a common cause of hyperandrogenism. Neonatal screening for CAH and gene-specific prenatal diagnosis are now possible. Standard hormone replacement fails to achieve normal growth and development for many children with CAH, and adults can experience iatrogenic Cushing's syndrome, hyperandrogenism, infertility, or the development of the metabolic syndrome. This Seminar reviews the epidemiology, genetics, pathophysiology, diagnosis, and management of CAH, and provides an overview of clinical challenges and future therapies.

  10. Benign prostatic hyperplasia.

    PubMed Central

    Simpson, R J

    1997-01-01

    The clinical syndrome of benign prostatic hyperplasia reflects a complex interplay between benign prostatic enlargement, which will affect almost all men by the age of 80, and the resulting outlet obstruction and lower urinary tract symptoms. The disease is now known to adversely affect the quality of life of around one man in three over the age of 50. New medical treatments and new surgical interventions are challenging the previous standard treatment of transurethral resection of prostate, which continues to have a morbidity of 17% and some mortality. Primary care will be increasingly involved in shared care with particular emphasis on monitoring of patients on watchful waiting medical therapy- and following operative intervention. PMID:9196969

  11. Active Magnetic Regenerative Liquefier

    SciTech Connect

    Barclay, John A.; Oseen-Send, Kathryn; Ferguson, Luke; Pouresfandiary, Jamshid; Cousins, Anand; Ralph, Heather; Hampto, Tom

    2016-01-12

    This final report for the DOE Project entitled Active Magnetic Regenerative Liquefier (AMRL) funded under Grant DE-FG36-08GO18064 to Heracles Energy Corporation d.b.a. Prometheus Energy (Heracles/Prometheus) describes an active magnetic regenerative refrigerator (AMRR) prototype designed and built during the period from July 2008 through May 2011. The primary goal of this project was to make significant technical advances toward highly efficient liquefaction of hydrogen. Conventional hydrogen liquefiers at any scale have a maximum FOM of ~0.35 due primarily to the intrinsic difficulty of rapid, efficient compression of either hydrogen or helium working gases. Numerical simulation modeling of high performance AMRL designs indicates certain designs have promise to increase thermodynamic efficiency from a FOM of ~0.35 toward ~0.5 to ~0.6. The technical approach was the use of solid magnetic working refrigerants cycled in and out of high magnetic fields to build an efficient active regenerative magnetic refrigeration module providing cooling power for AMRL. A single-stage reciprocating AMRR with a design temperature span from ~290 K to ~120 K was built and tested with dual magnetic regenerators moving in and out of the conductively-cooled superconducting magnet subsystem. The heat transfer fluid (helium) was coupled to the process stream (refrigeration/liquefaction load) via high performance heat exchangers. In order to maximize AMRR efficiency a helium bypass loop with adjustable flow was incorporated in the design because the thermal mass of magnetic refrigerants is higher in low magnetic field than in high magnetic field. Heracles/Prometheus designed experiments to measure AMRR performance under a variety of different operational parameters such as cycle frequency, magnetic field strength, heat transfer fluid flow rate, amount of bypass flow of the heat transfer fluid while measuring work input, temperature span, cooling capability as a function of cold temperature

  12. Hyperplasia vs hypertrophy in tissue regeneration after extensive liver resection

    PubMed Central

    Marongiu, Fabio; Marongiu, Michela; Contini, Antonella; Serra, Monica; Cadoni, Erika; Murgia, Riccardo; Laconi, Ezio

    2017-01-01

    AIM To address to what extent hypertrophy and hyperplasia contribute to liver mass restoration after major tissue loss. METHODS The ability of the liver to regenerate is remarkable on both clinical and biological grounds. Basic mechanisms underlying this process have been intensively investigated. However, it is still debated to what extent hypertrophy and hyperplasia contribute to liver mass restoration after major tissue loss. We addressed this issue using a genetically tagged system. We were able to follow the fate of single transplanted hepatocytes during the regenerative response elicited by 2/3 partial surgical hepatectomy (PH) in rats. Clusters of transplanted cells were 3D reconstructed and their size distribution was evaluated over time after PH. RESULTS Liver size and liver DNA content were largely recovered 10 d post-PH, as expected (e.g., total DNA/liver/100 g b.w. was 6.37 ± 0.21 before PH and returned to 6.10 ± 0.36 10 d after PH). Data indicated that about 2/3 of the original residual hepatocytes entered S-phase in response to PH. Analysis of cluster size distribution at 24, 48, 96 h and 10 d after PH revealed that about half of the remnant hepatocytes completed at least 2 cell cycles. Average size of hepatocytes increased at 24 h (248.50 μm2 ± 7.82 μm2, P = 0.0015), but returned to control values throughout the regenerative process (up to 10 d post-PH, 197.9 μm2 ± 6.44 μm2, P = 0.11). A sizeable fraction of the remnant hepatocyte population does not participate actively in tissue mass restoration. CONCLUSION Hyperplasia stands as the major mechanism contributing to liver mass restoration after PH, with hypertrophy playing a transient role in the process. PMID:28348481

  13. Regenerative periodontal therapy.

    PubMed

    Kao, Daniel W K; Fiorellini, Joseph P

    2012-01-01

    Traditional treatment for loss of bone and attachment due to periodontal disease has focused around repairing the damage induced. However, over the past few decades, clinicians have begun to utilize regenerative techniques to rebuild bone, cementum and the periodontal ligament. Conventional procedures most often involve the use of barrier membranes with bone grafts that foster selective cell repopulation and regrowth of osseous structures. Since the predictability of these techniques may be limited to certain case types, pharmacologically based efforts are underway to investigate the possibility of harnessing osseous regrowth potential. Clinical research has found that proteins are potent biological mediators that promote many of the events in wound healing, and have been shown to promote bone formation in human clinical studies.

  14. Regenerative braking device

    DOEpatents

    Hoppie, Lyle O.

    1982-01-12

    Disclosed are several embodiments of a regenerative braking device for an automotive vehicle. The device includes a plurality of rubber rollers (24, 26) mounted for rotation between an input shaft (14) connectable to the vehicle drivetrain and an output shaft (16) which is drivingly connected to the input shaft by a variable ratio transmission (20). When the transmission ratio is such that the input shaft rotates faster than the output shaft, the rubber rollers are torsionally stressed to accumulate energy, thereby slowing the vehicle. When the transmission ratio is such that the output shaft rotates faster than the input shaft, the rubber rollers are torsionally relaxed to deliver accumulated energy, thereby accelerating or driving the vehicle.

  15. Hydrogels in Regenerative Medicine

    PubMed Central

    Slaughter, Brandon V.; Khurshid, Shahana S.; Fisher, Omar Z.; Khademhosseini, Ali

    2015-01-01

    Hydrogels, due to their unique biocompatibility, flexible methods of synthesis, range of constituents, and desirable physical characteristics, have been the material of choice for many applications in regenerative medicine. They can serve as scaffolds that provide structural integrity to tissue constructs, control drug and protein delivery to tissues and cultures, and serve as adhesives or barriers between tissue and material surfaces. In this work, the properties of hydrogels that are important for tissue engineering applications and the inherent material design constraints and challenges are discussed. Recent research involving several different hydrogels polymerized from a variety of synthetic and natural monomers using typical and novel synthetic methods are highlighted. Finally, special attention is given to the microfabrication techniques that are currently resulting in important advances in the field. PMID:20882499

  16. PEM regenerative fuel cells

    NASA Technical Reports Server (NTRS)

    Swette, Larry L.; Laconti, Anthony B.; Mccatty, Stephen A.

    1993-01-01

    This paper will update the progress in developing electrocatalyst systems and electrode structures primarily for the positive electrode of single-unit solid polymer proton exchange membrane (PEM) regenerative fuel cells. The work was done with DuPont Nafion 117 in complete fuel cells (40 sq cm electrodes). The cells were operated alternately in fuel cell mode and electrolysis mode at 80 C. In fuel cell mode, humidified hydrogen and oxygen were supplied at 207 kPa (30 psi); in electrolysis mode, water was pumped over the positive electrode and the gases were evolved at ambient pressure. Cycling data will be presented for Pt-Ir catalysts and limited bifunctional data will be presented for Pt, Ir, Ru, Rh, and Na(x)Pt3O4 catalysts as well as for electrode structure variations.

  17. Regenerative combustion device

    DOEpatents

    West, Phillip B.

    2004-03-16

    A regenerative combustion device having a combustion zone, and chemicals contained within the combustion zone, such as water, having a first equilibrium state, and a second combustible state. Means for transforming the chemicals from the first equilibrium state to the second combustible state, such as electrodes, are disposed within the chemicals. An igniter, such as a spark plug or similar device, is disposed within the combustion zone for igniting combustion of the chemicals in the second combustible state. The combustion products are contained within the combustion zone, and the chemicals are selected such that the combustion products naturally chemically revert into the chemicals in the first equilibrium state following combustion. The combustion device may thus be repeatedly reused, requiring only a brief wait after each ignition to allow the regeneration of combustible gasses within the head space.

  18. The pharmacology of regenerative medicine.

    PubMed

    Christ, George J; Saul, Justin M; Furth, Mark E; Andersson, Karl-Erik

    2013-07-01

    Regenerative medicine is a rapidly evolving multidisciplinary, translational research enterprise whose explicit purpose is to advance technologies for the repair and replacement of damaged cells, tissues, and organs. Scientific progress in the field has been steady and expectations for its robust clinical application continue to rise. The major thesis of this review is that the pharmacological sciences will contribute critically to the accelerated translational progress and clinical utility of regenerative medicine technologies. In 2007, we coined the phrase "regenerative pharmacology" to describe the enormous possibilities that could occur at the interface between pharmacology, regenerative medicine, and tissue engineering. The operational definition of regenerative pharmacology is "the application of pharmacological sciences to accelerate, optimize, and characterize (either in vitro or in vivo) the development, maturation, and function of bioengineered and regenerating tissues." As such, regenerative pharmacology seeks to cure disease through restoration of tissue/organ function. This strategy is distinct from standard pharmacotherapy, which is often limited to the amelioration of symptoms. Our goal here is to get pharmacologists more involved in this field of research by exposing them to the tools, opportunities, challenges, and interdisciplinary expertise that will be required to ensure awareness and galvanize involvement. To this end, we illustrate ways in which the pharmacological sciences can drive future innovations in regenerative medicine and tissue engineering and thus help to revolutionize the discovery of curative therapeutics. Hopefully, the broad foundational knowledge provided herein will spark sustained conversations among experts in diverse fields of scientific research to the benefit of all.

  19. [Congenital Adrenal Hyperplasia in Adults].

    PubMed

    Vrbíková, Jana

    2016-01-01

    Congenital adrenal hyperplasia is a life-long disease requiring an integrated therapy. It may negatively influence the quality of life. In childhood, the main problems of the care of these patients involve sex determination and ensuring optimum growth and puberty. The therapeutic goals for adults are the prevention of Addisonian crisis and ensuring the best possible quality of life, including fertility.Key words: androgens - cardiovascular risk - congenital adrenal hyperplasia - bone density - testicular rest tumors.

  20. Congenital lipoid adrenal hyperplasia

    PubMed Central

    2014-01-01

    Congenital lipoid adrenal hyperplasia (lipoid CAH) is the most fatal form of CAH, as it disrupts adrenal and gonadal steroidogenesis. Most cases of lipoid CAH are caused by recessive mutations in the gene encoding steroidogenic acute regulatory protein (StAR). Affected patients typically present with signs of severe adrenal failure in early infancy and 46,XY genetic males are phenotypic females due to disrupted testicular androgen secretion. The StAR p.Q258X mutation accounts for about 70% of affected alleles in most patients of Japanese and Korean ancestry. However, it is more prevalent (92.3%) in the Korean population. Recently, some patients have been showed that they had late and mild clinical findings. These cases and studies constitute a new entity of 'nonclassic lipoid CAH'. The cholesterol side-chain cleavage enzyme, P450scc (CYP11A1), plays an essential role converting cholesterol to pregnenolone. Although progesterone production from the fetally derived placenta is necessary to maintain a pregnancy to term, some patients with P450scc mutations have recently been reported. P450scc mutations can also cause lipoid CAH and establish a recently recognized human endocrine disorder. PMID:25654062

  1. Benign prostatic hyperplasia

    PubMed Central

    2006-01-01

    Introduction Symptomatic benign prostatic hyperplasia (BPH) may affect up to 30% of men in their early 70s, causing urinary symptoms of bladder outlet obstruction. Symptoms can improve without treatment, but the usual course is a slow progression of symptoms, with acute urinary retention occurring in 1-2% of men with BPH per year. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of medical, surgical, and herbal treatments? We searched: Medline, Embase, The Cochrane Library and other important databases up to May 2005 (BMJ Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 43 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: 5 alpha-reductase inhibitors, alpha-blockers, beta-sitosterol plant extract, less-invasive surgical techniques, pygeum africanum, rye grass pollen extract, saw palmetto plant extracts, transurethral microwave thermotherapy, transurethral needle ablation, and transurethral resection.

  2. Decellularized scaffolds in regenerative medicine

    PubMed Central

    Yu, Yaling; Alkhawaji, Ali; Ding, Yuqiang; Mei, Jin

    2016-01-01

    Allogeneic organ transplantation remains the ultimate solution for end-stage organ failure. Yet, the clinical application is limited by the shortage of donor organs and the need for lifelong immunosuppression, highlighting the importance of developing effective therapeutic strategies. In the field of regenerative medicine, various regenerative technologies have lately been developed using various biomaterials to address these limitations. Decellularized scaffolds, derived mainly from various non-autologous organs, have been proved a regenerative capability in vivo and in vitro and become an emerging treatment approach. However, this regenerative capability varies between scaffolds as a result of the diversity of anatomical structure and cellular composition of organs used for decellularization. Herein, recent advances in scaffolds based on organ regeneration in vivo and in vitro are highlighted along with aspects where further investigations and analyses are needed. PMID:27486772

  3. Regenerative switching CMOS system

    DOEpatents

    Welch, James D.

    1998-01-01

    Complementary Metal Oxide Semiconductor (CMOS) Schottky barrier Field Effect Transistor systems, which are a seriesed combination of N and P-Channel MOSFETS, in which Source Schottky barrier junctions of the N and P-Channel Schottky barrier MOSFETS are electically interconnected, (rather than the Drains as in conventional diffused junction CMOS), which Schottky barrier MOSFET system demonstrates Regenerative Inverting Switching Characteristics in use are disclosed. Both the N and P-Channel Schottky barrier MOSFET devices are unique in that they provide operational Drain Current vs. Drain to Source voltage as a function of Gate voltage only where the polarities of the Drain voltage and Gate voltage are opposite, referenced to the Source as a common terminal, and where the polarity of the voltage applied to the Gate is appropriate to cause Channel inversion. Experimentally derived results which demonstrate and verify the operation of N and P-Channel Schottky barrier MOSFETS actually fabricated on P and N-type Silicon respectively, by a common procedure using vacuum deposited Chromium as a Schottky barrier forming metal, are also provided.

  4. Regenerative switching CMOS system

    DOEpatents

    Welch, J.D.

    1998-06-02

    Complementary Metal Oxide Semiconductor (CMOS) Schottky barrier Field Effect Transistor systems, which are a series combination of N and P-Channel MOSFETS, in which Source Schottky barrier junctions of the N and P-Channel Schottky barrier MOSFETS are electrically interconnected, (rather than the Drains as in conventional diffused junction CMOS), which Schottky barrier MOSFET system demonstrates Regenerative Inverting Switching Characteristics in use are disclosed. Both the N and P-Channel Schottky barrier MOSFET devices are unique in that they provide operational Drain Current vs. Drain to Source voltage as a function of Gate voltage only where the polarities of the Drain voltage and Gate voltage are opposite, referenced to the Source as a common terminal, and where the polarity of the voltage applied to the Gate is appropriate to cause Channel inversion. Experimentally derived results which demonstrate and verify the operation of N and P-Channel Schottky barrier MOSFETS actually fabricated on P and N-type Silicon respectively, by a common procedure using vacuum deposited Chromium as a Schottky barrier forming metal, are also provided. 14 figs.

  5. Personalized Regenerative Medicine.

    PubMed

    Arjmand, Babak; Goodarzi, Parisa; Mohamadi-Jahani, Fereshteh; Falahzadeh, Khadijeh; Larijani, Bagher

    2017-03-01

    Personalized medicine as a novel field of medicine refers to the prescription of specific therapeutics procedure for an individual. This approach has established based on pharmacogenetic and pharmacogenomic information and data. The terms precision and personalized medicines are sometimes applied interchangeably. However, there has been a shift from "personalized medicine" towards "precision medicine". Although personalized medicine emerged from pharmacogenetics, nowadays it covers many fields of healthcare. Accordingly, regenerative medicine and cellular therapy as the new fields of medicine use cell-based products in order to develop personalized treatments. Different sources of stem cells including mesenchymal stem cells, embryonic stem cells and induced pluripotent stem cells (iPSCs) have been considered in targeted therapies which could give many advantages. iPSCs as the novel and individual pluripotent stem cells have been introduced as the appropriate candidates for personalized cell therapies. Cellular therapies can provide a personalized approach. Because of person-to-person and population differences in the result of stem cell therapy, individualized cellular therapy must be adjusted according to the patient specific profile, in order to achieve best therapeutic results and outcomes. Several factors should be considered to achieve personalized stem cells therapy such as, recipient factors, donor factors, and the overall body environment in which the stem cells could be active and functional. In addition to these factors, the source of stem cells must be carefully chosen based on functional and physical criteria that lead to optimal outcomes.

  6. Thermally regenerative fuel cells

    NASA Astrophysics Data System (ADS)

    Ludwig, F. A.; Kindler, A.; McHardy, J.

    1991-10-01

    The three phase project was undertaken to investigate solventless ionic liquids as possible working fluids for a new type of thermally regenerative fuel cell (TRFC). The heart of the new device, invented at Hughes Aircraft Company in 1983, is an electrochemical concentration cell where acid and base streams react to produce electrical energy. Thermal energy is then used to decompose the resulting salts and regenerate the cell reactants. In principle, a TRFC can be matched to any source of thermal energy simply by selecting working fluids with the appropriate regeneration temperature. However, aqueous working fluids (the focus of previous studies) impose limitations on both the operating temperatures and the achievable energy densities. It was the need to overcome these limitations that prompted the present investigation. Specific aims were to identify possible working fluids for TRFC systems with both low and high regeneration temperatures. A major advantage of our aqueous-fluid TRFC systems has been the ability to use hydrogen electrodes. The low activation and mass transfer losses of these electrodes contribute substantially to overall system efficiency.

  7. Pharmacotherapy for benign prostatic hyperplasia.

    PubMed Central

    Narayan, P; Indudhara, R

    1994-01-01

    Benign prostatic hyperplasia is a benign neoplasm of the prostate seen in men of advancing age. Microscopic evidence of the disorder is seen in about 70% of men by 70 years of age, whereas symptoms requiring some form of surgical intervention occur in 30% of men during their lifetime. Although the exact cause of benign prostatic hyperplasia is not clear, it is well recognized that high levels of intraprostatic androgens are required for the maintenance of prostatic growth. In recent years, extensive surveys of patients undergoing transurethral resection of the prostate reveal an 18% incidence of morbidity that has essentially not changed in the past 30 years. This procedure is also the second highest reimbursed surgical therapy under Medicare. These findings have resulted in an intensive search for alternative therapies for prostatic hyperplasia. An alternative that has now been well defined is the use of alpha-adrenergic blockers to relax the prostatic urethra. This is based on findings that a major component of benign prostatic hyperplasia symptoms is spasm of the prostatic urethra and bladder neck, which is mediated by the alpha-adrenergic nerves. A second approach is to block androgens involved in maintaining prostate growth. Several such drugs are now available for clinical use, and we discuss their side effects and use. We also include the newer recommendations on evaluating benign prostatic hyperplasia that are cost-effective yet comprehensive. Images PMID:7528957

  8. Intimal hyperplasia: slow but deadly.

    PubMed

    Mills, B; Robb, T; Larson, D F

    2012-11-01

    Intimal hyperplasia is the leading cause of long-term failure in coronary artery bypass vein grafting, coronary artery stenting, angioplasty, arteriovenous fistula for dialysis, and allograft transplantation. Intimal hyperplasia is a product of vascular smooth muscle cell proliferation, migration through the internal elastic lamina, and deposition of extracellular matrix proteins driven by growth factors in the vasculature. This vascular pathology results in a progressive diminution of the vessel lumen and serves as a site for thrombosis and atherosclerotic lesions. A key cell type in the initiation of intimal hyperplasia is the vascular endothelial cell, which appears to have down-stream effects on the vascular smooth muscle proliferation and migration. Currently, the only means available for prevention of intimal hyperplasia is through inhibition of mammalian target of rapamycin (mTOR) with the immunosuppressant rapamycin. mTOR integrates up-stream signals from growth factors such as IL-2 and senses the cellular nutrient and energy levels and redox status. This presentation will discuss the potential means of preserving the vascular endothelial cell and, thereby, reducing the development of intimal hyperplasia in our open-heart surgical patients.

  9. The Pharmacology of Regenerative Medicine

    PubMed Central

    Saul, Justin M.; Furth, Mark E.; Andersson, Karl-Erik

    2013-01-01

    Regenerative medicine is a rapidly evolving multidisciplinary, translational research enterprise whose explicit purpose is to advance technologies for the repair and replacement of damaged cells, tissues, and organs. Scientific progress in the field has been steady and expectations for its robust clinical application continue to rise. The major thesis of this review is that the pharmacological sciences will contribute critically to the accelerated translational progress and clinical utility of regenerative medicine technologies. In 2007, we coined the phrase “regenerative pharmacology” to describe the enormous possibilities that could occur at the interface between pharmacology, regenerative medicine, and tissue engineering. The operational definition of regenerative pharmacology is “the application of pharmacological sciences to accelerate, optimize, and characterize (either in vitro or in vivo) the development, maturation, and function of bioengineered and regenerating tissues.” As such, regenerative pharmacology seeks to cure disease through restoration of tissue/organ function. This strategy is distinct from standard pharmacotherapy, which is often limited to the amelioration of symptoms. Our goal here is to get pharmacologists more involved in this field of research by exposing them to the tools, opportunities, challenges, and interdisciplinary expertise that will be required to ensure awareness and galvanize involvement. To this end, we illustrate ways in which the pharmacological sciences can drive future innovations in regenerative medicine and tissue engineering and thus help to revolutionize the discovery of curative therapeutics. Hopefully, the broad foundational knowledge provided herein will spark sustained conversations among experts in diverse fields of scientific research to the benefit of all. PMID:23818131

  10. Focal epithelial hyperplasia: Case report.

    PubMed

    Puriene, Alina; Rimkevicius, Arunas; Gaigalas, Mindaugas

    2011-01-01

    The purpose of the present article is to present a 15 year-old patient with focal epithelial hyperplasia and to review the references on the subject-related etiological, pathological, diagnostic and treatment aspects. Focal epithelial hyperplasia is a rare human papilloma virus (HPV) related to oral lesion with very low frequency within our population. Surgical treatment with a biopsy was performed, acanthosis and parakeratosis are consistent histopathological features, since the patient had no history of sexual contact and HIV infection, the virus was probably acquired from environmental sources.

  11. Myometrial dysplasia (atypical myometrial hyperplasia).

    PubMed

    Cramer, Stewart F; Newcomb, Patricia M; Bonfiglio, Thomas A

    2007-04-01

    Although precursor lesions are well known for cervical and endometrial neoplasms, precursor lesions are not currently recognized for the most common tumor of the uterus-leiomyomas. Myometrial hyperplasia has been recently described and evaluated by morphometry, but its relationship to uterine leiomyomas has not been systematically explored. Myometrial dysplasia (atypical myometrial hyperplasia) has not been previously recognized. We herein report a case of myometrial dysplasia with immunostains for proliferation marker MIB-1 (Ki-67) and for p53. The paradoxical rarity of myometrial dysplasia is considered in comparison to the striking frequency of uterine leiomyomas.

  12. Biomaterials for Bone Regenerative Engineering.

    PubMed

    Yu, Xiaohua; Tang, Xiaoyan; Gohil, Shalini V; Laurencin, Cato T

    2015-06-24

    Strategies for bone tissue regeneration have been continuously evolving for the last 25 years since the introduction of the "tissue engineering" concept. The convergence of the life, physical, and engineering sciences has brought in several advanced technologies available to tissue engineers and scientists. This resulted in the creation of a new multidisciplinary field termed as "regenerative engineering". In this article, the role of biomaterials in bone regenerative engineering is systematically reviewed to elucidate the new design criteria for the next generation of biomaterials for bone regenerative engineering. The exemplary design of biomaterials harnessing various materials characteristics towards successful bone defect repair and regeneration is highlighted. Particular attention is given to the attempts of incorporating advanced materials science, stem cell technologies, and developmental biology into biomaterials design to engineer and develop the next generation bone grafts.

  13. Bio-regenerative life support

    NASA Technical Reports Server (NTRS)

    Macelroy, Robert D.; Wydeven, Theodore, Jr.

    1989-01-01

    The basis for and the potential uses of bio-regenerative life support are examined. Bio-regenerative life support systems are an alternative to physical-chemical regeneration techniques for use when resupply of a crew in space is expensive, or when the logistics of resupply are difficult. Many of the scientific studies required for bio-regenerative life support systems have been completed and preliminary development of some components will begin within the next 12 to 18 months. The focus of the work that lies ahead will be efficient power and mass use, long-term system stability, component function, systems integration, and extensive testing in the space environment. Because of the advantages of bio-regeneration, it is anticipated that human life support for long-term space missions will evolve to include increasingly large amounts of biologically-based regeneration.

  14. Rare presentation of sebaceous hyperplasia

    PubMed Central

    Lester, Rachael A; Torgerson, Rochelle R; Sandhu, Nicole P

    2014-01-01

    A 23-year-old woman presented with an 8-month history of asymptomatic thickening of the central areola bilaterally and oily nipple discharge. On examination, there were yellowish-pink papules coalescing into plaques bilaterally. Biopsy showed ectopic sebaceous glands (Montgomery tubercles), known as bilateral areolar sebaceous hyperplasia. PMID:24759166

  15. Thermoacoustic simulator for regenerative machines

    NASA Astrophysics Data System (ADS)

    Luo, E.; Wu, J.; Yang, J.; Xiao, J.

    2002-05-01

    Linear thermoacoustic theory is a powerful tool to understand the working mechanism of many regenerative machines. Based on the theory, the authors have developed a computer code "Thermoacoustic Simulator" for analyzing and designing different regenerative cryocoolers including String refrigerators, Stirling and G-M types of pulse tube refrigerators and G-M cryocoolers. Also, standing-wave and traveling-wave thermoacoustic machines can be simulated, too. This paper will present the philosophy of the "Thermoacoustic Simulator" and some demonstrations of simulation for different types of cryocoolers and thermoacoustic engines.

  16. Regenerative Endodontics by Cell Homing.

    PubMed

    He, Ling; Zhong, Juan; Gong, Qimei; Cheng, Bin; Kim, Sahng G; Ling, Junqi; Mao, Jeremy J

    2017-01-01

    Apical revascularization (AR) and platelet-rich plasma have been used to restore dental pulp vitality in infected immature permanent teeth. Two regenerative therapies are cell transplantation and cell homing. This article updates and benchmarks these therapies with cell homing. A case report concluded that AR increased root length; however, quantitative and statistical assessments disproved this. Regenerative endodontic therapies require prospective clinical trials demonstrating safety and efficacy. These therapies are intrinsically susceptible to procedural and patient variations. Cell homing uses novel molecules that drive therapeutic efficacy, and may be less sensitive to procedural and patient variations.

  17. Regeneratively Cooled Porous Media Jacket

    NASA Technical Reports Server (NTRS)

    Mungas, Greg (Inventor); Fisher, David J. (Inventor); London, Adam Pollok (Inventor); Fryer, Jack Merrill (Inventor)

    2013-01-01

    The fluid and heat transfer theory for regenerative cooling of a rocket combustion chamber with a porous media coolant jacket is presented. This model is used to design a regeneratively cooled rocket or other high temperature engine cooling jacket. Cooling jackets comprising impermeable inner and outer walls, and porous media channels are disclosed. Also disclosed are porous media coolant jackets with additional structures designed to transfer heat directly from the inner wall to the outer wall, and structures designed to direct movement of the coolant fluid from the inner wall to the outer wall. Methods of making such jackets are also disclosed.

  18. Laser system using regenerative amplifier

    DOEpatents

    Emmett, J.L.

    1980-03-04

    High energy laser system is disclosed using a regenerative amplifier, which relaxes all constraints on laser components other than the intrinsic damage level of matter, so as to enable use of available laser system components. This can be accomplished by use of segmented components, spatial filters, at least one amplifier using solid state or gaseous media, and separated reflector members providing a long round trip time through the regenerative cavity, thereby allowing slower switching and adequate time to clear the spatial filters, etc. The laser system simplifies component requirements and reduces component cost while providing high energy output. 10 figs.

  19. [Frequency of Kongenital Adrenal Hyperplasia (author's transl)].

    PubMed

    Müller, W; Prader, M; Kofler, J; Glatzl, J; Geir, W

    1979-01-01

    The frequency of homozygous congenital adrenal hyperplasia in Tyrol is found to be 1 : 8991, the gene-frequency for congenital adrenal hyperplasia 1 : 95 and the frequency of heterozygous congenital adrenal hyperplasia 1 : 48. Our data is compared on a numerical and statistical base with that in Zürich and Munich with regard to the frequency of congenital adrenal hyperplasia, to its distribution with and without salt loss and to its sex-distribution. According to our study one may assume a frequency of homozygous congenital adrenal hyperplasia in Tyrol, Zürich and Munich of 1 : 7000--10,000.

  20. Nondestructive test of regenerative chambers

    NASA Technical Reports Server (NTRS)

    Malone, G. A.; Stauffis, R.; Wood, R.

    1972-01-01

    Flat panels simulating internally cooled regenerative thrust chamber walls were fabricated by electroforming, brazing and diffusion bonding to evaluate the feasibility of nondestructive evaluation techniques to detect bonds of various strength integrities. Ultrasonics, holography, and acoustic emission were investigated and found to yield useful and informative data regarding the presence of bond defects in these structures.

  1. Regenerative Strategies for Craniofacial Disorders

    PubMed Central

    Garland, Catharine B.; Pomerantz, Jason H.

    2012-01-01

    Craniofacial disorders present markedly complicated problems in reconstruction because of the complex interactions of the multiple, simultaneously affected tissues. Regenerative medicine holds promise for new strategies to improve treatment of these disorders. This review addresses current areas of unmet need in craniofacial reconstruction and emphasizes how craniofacial tissues differ from their analogs elsewhere in the body. We present a problem-based approach to illustrate current treatment strategies for various craniofacial disorders, to highlight areas of need, and to suggest regenerative strategies for craniofacial bone, fat, muscle, nerve, and skin. For some tissues, current approaches offer excellent reconstructive solutions using autologous tissue or prosthetic materials. Thus, new “regenerative” approaches would need to offer major advantages in order to be adopted. In other tissues, the unmet need is great, and we suggest the greatest regenerative need is for muscle, skin, and nerve. The advent of composite facial tissue transplantation and the development of regenerative medicine are each likely to add important new paradigms to our treatment of craniofacial disorders. PMID:23248598

  2. Biomimetic microenvironments for regenerative endodontics.

    PubMed

    Kaushik, Sagar N; Kim, Bogeun; Walma, Alexander M Cruz; Choi, Sung Chul; Wu, Hui; Mao, Jeremy J; Jun, Ho-Wook; Cheon, Kyounga

    2016-01-01

    Regenerative endodontics has been proposed to replace damaged and underdeveloped tooth structures with normal pulp-dentin tissue by providing a natural extracellular matrix (ECM) mimicking environment; stem cells, signaling molecules, and scaffolds. In addition, clinical success of the regenerative endodontic treatments can be evidenced by absence of signs and symptoms; no bony pathology, a disinfected pulp, and the maturation of root dentin in length and thickness. In spite of the various approaches of regenerative endodontics, there are several major challenges that remain to be improved: a) the endodontic root canal is a strong harbor of the endodontic bacterial biofilm and the fundamental etiologic factors of recurrent endodontic diseases, (b) tooth discolorations are caused by antibiotics and filling materials, (c) cervical root fractures are caused by endodontic medicaments, (d) pulp tissue is not vascularized nor innervated, and (e) the dentin matrix is not developed with adequate root thickness and length. Generally, current clinical protocols and recent studies have shown a limited success of the pulp-dentin tissue regeneration. Throughout the various approaches, the construction of biomimetic microenvironments of pulp-dentin tissue is a key concept of the tissue engineering based regenerative endodontics. The biomimetic microenvironments are composed of a synthetic nano-scaled polymeric fiber structure that mimics native pulp ECM and functions as a scaffold of the pulp-dentin tissue complex. They will provide a framework of the pulp ECM, can deliver selective bioactive molecules, and may recruit pluripotent stem cells from the vicinity of the pulp apex. The polymeric nanofibers are produced by methods of self-assembly, electrospinning, and phase separation. In order to be applied to biomedical use, the polymeric nanofibers require biocompatibility, stability, and biodegradability. Therefore, this review focuses on the development and application of the

  3. Nanotechnology Biomimetic Cartilage Regenerative Scaffolds

    PubMed Central

    Sardinha, Jose Paulo; Myers, Simon

    2014-01-01

    Cartilage has a limited regenerative capacity. Faced with the clinical challenge of reconstruction of cartilage defects, the field of cartilage engineering has evolved. This article reviews current concepts and strategies in cartilage engineering with an emphasis on the application of nanotechnology in the production of biomimetic cartilage regenerative scaffolds. The structural architecture and composition of the cartilage extracellular matrix and the evolution of tissue engineering concepts and scaffold technology over the last two decades are outlined. Current advances in biomimetic techniques to produce nanoscaled fibrous scaffolds, together with innovative methods to improve scaffold biofunctionality with bioactive cues are highlighted. To date, the majority of research into cartilage regeneration has been focused on articular cartilage due to the high prevalence of large joint osteoarthritis in an increasingly aging population. Nevertheless, the principles and advances are applicable to cartilage engineering for plastic and reconstructive surgery. PMID:24883273

  4. Electrospun Nanofibers for Regenerative Medicine**

    PubMed Central

    Liu, Wenying; Thomopoulos, Stavros

    2013-01-01

    This article reviews recent progress in applying electrospun nanofibers to the emerging field of regenerative medicine. We begin with a brief introduction to electrospinning and nanofibers, with a focus on issues related to the selection of materials, incorporation of bioactive molecules, degradation characteristics, control of mechanical properties, and facilitation of cell infiltration. We then discuss a number of approaches to fabrication of scaffolds from electrospun nanofibers, including techniques for controlling the alignment of nanofibers and for producing scaffolds with complex architectures. We also highlight applications of the nanofiber-based scaffolds in four areas of regenerative medicine that involve nerves, dural tissues, tendons, and the tendon-to-bone insertion site. We conclude this review with perspectives on challenges and future directions for design, fabrication, and utilization of scaffolds based on electrospun nanofibers. PMID:23184683

  5. The unitized regenerative fuel cell

    SciTech Connect

    1997-05-01

    Fuel cells can operate on hydrogen fuel and oxygen from air. If the fuel cell is designed to also operate in reverse as an electrolyzer, then electricity can be used to convert the water back into hydrogen and oxygen. This dual function system is known as a reversible or unitized regenerative fuel cell. This is an excellent energy source in situations where weight is a concern.

  6. Regenerative endodontics: regeneration or repair?

    PubMed

    Simon, Stéphane R J; Tomson, Phillip L; Berdal, Ariane

    2014-04-01

    Recent advances in biotechnology and translational research have made it possible to provide treatment modalities that protect the vital pulp, allow manipulation of reactionary and reparative dentinogenesis, and, more recently, permit revascularization of an infected root canal space. These approaches are referred to as regenerative procedures. The method currently used to determine the origin of the tissue secreted during the repair/regeneration process is largely based on the identification of cellular markers (usually proteins) left by cells that were responsible for this tissue production. The presence of these proteins in conjunction with other indicators of cellular behavior (especially biomineralization) and analysis of the structure of the newly generated tissue allow conclusions to be made of how it was formed. Thus far, it has not been possible to truly establish the biological mechanism controlling tertiary dentinogenesis. This article considers current therapeutic techniques to treat the dentin-pulp complex and contextualize them in terms of reparative and regenerative processes. Although it may be considered a semantic argument rather than a biological one, the definitions of regeneration and repair are explored to clarify our position in this era of regenerative endodontics.

  7. Current research on regenerative systems.

    PubMed

    Shapira, J; Mandel, A D; Quattrone, P D; Bell, N L

    1969-01-01

    Multiple studies directed toward the development of a regenerative life support system have shown that easily synthesized organic compounds and microbiological materials are potentially capable of being used as foods for long-duration space missions. Animal feeding studies have supported these views. The organic compounds presently believed to offer the greatest potential are glycerol, simple glycerol derivatives such as triacetin, and formose sugars. Laboratory studies indicate that glycerol can be synthesized from formaldehyde which in turn is obtained by the direct catalytic oxidation of methane, a by-product of the Sabatier reaction used in spacecraft atmosphere control system. Formose sugars are derived from the self-condensation of formaldehyde. Mixtures of glycerol and triacetin have been shown to be suitable as a major component of diets fed to weanling rats for prolonged periods. These compounds do not exist as stereoisomers and therefore offer advantages over the formose sugars. Hydrogenomonas eutropha is the microbiological system under investigation. An automated system for the continuous autotrophic production of Hydrogenomonas bacteria is in operation, and the nutritional requirements for growth in the system using urea as a nitrogen source are being studied. Nutritional evaluation of Hydrogenomonas bacteria has shown they are capable of supplying the total protein requirement of growing rats for prolonged periods. The potential and problems of these regenerative systems and the prospects for the accomplishment of a totally regenerative food system will be discussed.

  8. A review on endogenous regenerative technology in periodontal regenerative medicine.

    PubMed

    Chen, Fa-Ming; Zhang, Jing; Zhang, Min; An, Ying; Chen, Fang; Wu, Zhi-Fen

    2010-11-01

    Periodontitis is a globally prevalent inflammatory disease that causes the destruction of the tooth-supporting apparatus and potentially leads to tooth loss. Currently, the methods to reconstitute lost periodontal structures (i.e. alveolar bone, periodontal ligament, and root cementum) have relied on conventional mechanical, anti-infective modalities followed by a range of regenerative procedures such as guided tissue regeneration, the use of bone replacement grafts and exogenous growth factors (GFs), and recently developed tissue engineering technologies. However, all current or emerging paradigms have either been shown to have limited and variable outcomes or have yet to be developed for clinical use. To accelerate clinical translation, there is an ongoing need to develop therapeutics based on endogenous regenerative technology (ERT), which can stimulate latent self-repair mechanisms in patients and harness the host's innate capacity for regeneration. ERT in periodontics applies the patient's own regenerative 'tools', i.e. patient-derived GFs and fibrin scaffolds, sometimes in association with commercialized products (e.g. Emdogain and Bio-Oss), to create a material niche in an injured site where the progenitor/stem cells from neighboring tissues can be recruited for in situ periodontal regeneration. The choice of materials and the design of implantable devices influence therapeutic potential and the number and invasiveness of the associated clinical procedures. The interplay and optimization of each niche component involved in ERT are particularly important to comprehend how to make the desired cell response safe and effective for therapeutics. In this review, the emerging opportunities and challenges of ERT that avoid the ex vivo culture of autologous cells are addressed in the context of new approaches for engineering or regeneration of functional periodontal tissues by exploiting the use of platelet-rich products and its associated formulations as key

  9. Pituicytoma Coexisting With Corticotroph Hyperplasia

    PubMed Central

    Guo, Xiaopeng; Fu, Hanhui; Kong, Xiangyi; Gao, Lu; Wang, Wenze; Ma, Wenbin; Yao, Yong; Wang, Renzhi; Xing, Bing

    2016-01-01

    Abstract Pituicytoma is a rare, low-grade glial neoplasm that arises in the neurohypophysis or infundibulum and usually presents as pituitary gland enlargement. They are often misdiagnosed as pituitary adenomas. Causes have varied for high serum adrenocorticotropic hormone level reported in a few patients with pituicytoma. We report a rare case of pituicytoma accompanied by corticotroph hyperplasia—a challenging diagnosis guided by clinical presentations, radiological signs, and biopsy. We present a case of pituicytoma with corticotroph hyperplasia in a 46-year-old woman with typical Cushing syndrome. Magnetic resonance imaging revealed a lesion in the sellar area with equal T1 and T2 signals and marked homogeneous enhancement. We present detailed analysis of the patient's disease course and review pertinent literature. Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor of this journal. Because of this, there is no need to conduct special ethic review and the ethical approval is not necessary. The patient underwent a surgical exploration and tumor resection through a trans-sphenoidal approach. Pathologic results revealed pituicytoma and corticotroph hyperplasia. As adrenocorticotropic hormone and cortisol levels did not decrease to normal, the patient received radiotherapy and recovered uneventfully. No recurrence was found over 8 years of follow-up. Pituicytoma is a rare type of sellar tumor. Pituicytomas in patients with Cushing syndrome are rarer still. To our knowledge, this is the first report of Cushing syndrome caused by corticotroph hyperplasia in a pituicytoma patient. PMID:26962837

  10. Focal epithelial hyperplasia: Heck disease.

    PubMed

    Cohen, P R; Hebert, A A; Adler-Storthz, K

    1993-09-01

    Two sisters of Mexican ancestry had focal epithelial hyperplasia (FEH). The lesions on the oral mucosa of the older child were initially misinterpreted as representing sexual abuse. Microscopic evaluation of a hematoxylin and eosin-stained section from a lower lip papule demonstrated the histologic features of FEH. Although human papillomavirus (HPV) type 13 and HPV32 have been most consistently present in FEH lesions, types 6, 11, 13, and 32 were not detected in the paraffin-embedded tissue specimen of our patient using an in situ hybridization technique. The lesions persisted or recurred during management using destructive modalities; subsequently, they completely resolved spontaneously.

  11. Benign Prostatic Hyperplasia: An Overview

    PubMed Central

    Roehrborn, Claus G

    2005-01-01

    Despite the deceptively simple description of benign prostatic hyperplasia (BPH), the actual relationship between BPH, lower urinary tract symptoms (LUTS), benign prostatic enlargement, and bladder outlet obstruction is complex and requires a solid understanding of the definitional issues involved. The etiology of BPH and LUTS is still poorly understood, but the hormonal hypothesis has many arguments in its favor. There are many medical and minimally invasive treatment options available for affected patients. In the intermediate and long term, minimally invasive treatment options are superior to medical therapy in terms of symptom and flow rate improvement; tissue ablative surgical treatment options are superior to both minimally invasive and medical therapy. PMID:16985902

  12. Hyperplasia in glands with hormone excess.

    PubMed

    Marx, Stephen J

    2016-01-01

    Five syndromes share predominantly hyperplastic glands with a primary excess of hormones: neonatal severe primary hyperparathyroidism, from homozygous mutated CASR, begins severely in utero; congenital non-autoimmune thyrotoxicosis, from mutated TSHR, varies from severe with fetal onset to mild with adult onset; familial male-limited precocious puberty, from mutated LHR, expresses testosterone oversecretion in young boys; hereditary ovarian hyperstimulation syndrome, from mutated FSHR, expresses symptomatic systemic vascular permeabilities during pregnancy; and familial hyperaldosteronism type IIIA, from mutated KCNJ5, presents in young children with hypertension and hypokalemia. The grouping of these five syndromes highlights predominant hyperplasia as a stable tissue endpoint and as their tissue stage for all of the hormone excess. Comparisons were made among this and two other groups of syndromes, forming a continuum of gland staging: predominant oversecretions express little or no hyperplasia; predominant hyperplasias express little or no neoplasia; and predominant neoplasias express nodules, adenomas, or cancers. Hyperplasias may progress (5 of 5) to neoplastic stages while predominant oversecretions rarely do (1 of 6; frequencies differ P<0.02). Hyperplasias do not show tumor multiplicity (0 of 5) unlike neoplasias that do (13 of 19; P<0.02). Hyperplasias express mutation of a plasma membrane-bound sensor (5 of 5), while neoplasias rarely do (3 of 14; P<0.002). In conclusion, the multiple distinguishing themes within the hyperplasias establish a robust pathophysiology. It has the shared and novel feature of mutant sensors in the plasma membrane, suggesting that these are major contributors to hyperplasia.

  13. Nodular extramammary Paget disease with fibroepitheliomatous hyperplasia.

    PubMed

    Kim, Joung Soo; Jeong, Myeong Gil; Kang, Ho Song; Yu, Hee Joon

    2014-12-01

    Extramammary Paget disease (EMPD) is a rare skin condition usually found in the anogenital region. Histologically, EMPD may be associated with varying degrees of epidermal hyperplasia classified as squamous, papillomatous, or fibroepitheliomatous. We report a case of EMPD in a 90-year-old man who presented with well-demarcated plaques and a nodule in the pubic area with fibroepitheliomatous hyperplasia.

  14. Regenerative Engineering and Bionic Limbs

    PubMed Central

    James, Roshan; Laurencin, Cato T.

    2015-01-01

    Amputations of the upper extremity are severely debilitating, current treatments support very basic limb movement, and patients undergo extensive physiotherapy and psychological counselling. There is no prosthesis that allows the amputees near-normal function. With increasing number of amputees due to injuries sustained in accidents, natural calamities and international conflicts, there is a growing requirement for novel strategies and new discoveries. Advances have been made in technological, material and in prosthesis integration where researchers are now exploring artificial prosthesis that integrate with the residual tissues and function based on signal impulses received from the residual nerves. Efforts are focused on challenging experts in different disciplines to integrate ideas and technologies to allow for the regeneration of injured tissues, recording on tissue signals and feed-back to facilitate responsive movements and gradations of muscle force. A fully functional replacement and regenerative or integrated prosthesis will rely on interface of biological process with robotic systems to allow individual control of movement such as at the elbow, forearm, digits and thumb in the upper extremity. Regenerative engineering focused on the regeneration of complex tissue and organ systems will be realized by the cross-fertilization of advances over the past thirty years in the fields of tissue engineering, nanotechnology, stem cell science, and developmental biology. The convergence of toolboxes crated within each discipline will allow interdisciplinary teams from engineering, science, and medicine to realize new strategies, mergers of disparate technologies, such as biophysics, smart bionics, and the healing power of the mind. Tackling the clinical challenges, interfacing the biological process with bionic technologies, engineering biological control of the electronic systems, and feed-back will be the important goals in regenerative engineering over the next

  15. Advanced regenerative absorption refrigeration cycles

    DOEpatents

    Dao, Kim

    1990-01-01

    Multi-effect regenerative absorption cycles which provide a high coefficient of performance (COP) at relatively high input temperatures. An absorber-coupled double-effect regenerative cycle (ADR cycle) (10) is provided having a single-effect absorption cycle (SEA cycle) (11) as a topping subcycle and a single-effect regenerative absorption cycle (1R cycle) (12) as a bottoming subcycle. The SEA cycle (11) includes a boiler (13), a condenser (21), an expansion device (28), an evaporator (31), and an absorber (40), all operatively connected together. The 1R cycle (12) includes a multistage boiler (48), a multi-stage resorber (51), a multisection regenerator (49) and also uses the condenser (21), expansion device (28) and evaporator (31) of the SEA topping subcycle (11), all operatively connected together. External heat is applied to the SEA boiler (13) for operation up to about 500 degrees F., with most of the high pressure vapor going to the condenser (21) and evaporator (31) being generated by the regenerator (49). The substantially adiabatic and isothermal functioning of the SER subcycle (12) provides a high COP. For higher input temperatures of up to 700 degrees F., another SEA cycle (111) is used as a topping subcycle, with the absorber (140) of the topping subcycle being heat coupled to the boiler (13) of an ADR cycle (10). The 1R cycle (12) itself is an improvement in that all resorber stages (50b-f) have a portion of their output pumped to boiling conduits (71a-f) through the regenerator (49), which conduits are connected to and at the same pressure as the highest pressure stage (48a) of the 1R multistage boiler (48).

  16. Regenerative superheated steam turbine cycles

    NASA Technical Reports Server (NTRS)

    Fuller, L. C.; Stovall, T. K.

    1980-01-01

    PRESTO computer program was developed to analyze performance of wide range of steam turbine cycles with special attention given to regenerative superheated steam turbine cycles. It can be used to model standard turbine cycles, including such features as process steam extraction, induction and feedwater heating by external sources, peaking, and high back pressure. Expansion line efficiencies, exhaust loss, leakages, mechanical losses, and generator losses are used to calculate cycle heat rate and generator output. Program provides power engineer with flexible aid for design and analysis of steam turbine systems.

  17. Wavelength tunable alexandrite regenerative amplifier

    SciTech Connect

    Harter, D.J.; Bado, P.

    1988-11-01

    We describe a wavelength tunable alexandrite regenerative amplifier which is used to amplify nanosecond slices from a single-frequency cw dye laser or 50-ps pulses emitted by a diode laser to energies in the 10-mJ range. The amplified 5-ns slices generated by the cw-pumped line narrowed dye laser are Fourier transform limited. The 50-ps pulses emitted by a gain-switched diode laser are amplified by more than 10 orders of magnitude in a single stage.

  18. Optimal performance of regenerative cryocoolers

    NASA Astrophysics Data System (ADS)

    de Boer, P. C. T.

    2011-02-01

    The key component of a regenerative cryocooler is its regenerative heat exchanger. This device is subject to losses due to imperfect heat transfer between the regenerator material and the gas, as well as due to viscous dissipation. The relative magnitudes of these losses can be characterized by the ratio of the Stanton number St to the Fanning friction factor f. Using available data for the ratio St/ f, results are developed for the optimal cooling rate and Carnot efficiency. The variations of pressure and temperature are taken to be sinusoidal in time, and to have small amplitudes. The results are applied to the case of the Stirling cryocooler, with flow being generated by pistons at both sides of the regenerator. The performance is found to be close to optimal at large ratio of the warm space volume to the regenerator void volume. The results are also applied to the Orifice Pulse Tube Refrigerator. In this case, optimal performance additionally requires a large ratio of the regenerator void volume to the cold space volume.

  19. Lessons from developmental biology for regenerative medicine.

    PubMed

    Turner, Neill J; Keane, Timothy J; Badylak, Stephen F

    2013-09-01

    The ultimate goal of regenerative medicine is the functional restoration of lost or damaged tissues and organs. Since most tissues in man lack true regenerative properties and instead respond to injury with an inflammatory response and scar tissue formation, regenerative medicine strategies that include combinations of cells, scaffolds, and bioactive molecules to replace injured or missing tissues have been developed. The physical, chemical, and electrical cues that define the microenvironmental niche and the effect of these influences upon cell behavior during development are of interest to developmental biologists, with obvious overlap to the interest of the regenerative medicine field. This manuscript provides an overview of current approaches for tissue restoration being investigated in the field of regenerative medicine and attempts to identify areas of mutual beneficial interest with the field of developmental biology.

  20. Focal epithelial hyperplasia - an update.

    PubMed

    Said, Ahmed K; Leao, Jair C; Fedele, Stefano; Porter, Stephen R

    2013-07-01

    Focal epithelial hyperplasia (FEH) is an asymptomatic benign mucosal disease, which is mostly observed in specific groups in certain geographical regions. FEH is usually a disease of childhood and adolescence and is generally associated with people who live in poverty and of low socioeconomic status. Clinically, FEH is typically characterized by multiple, painless, soft, sessile papules, plaques or nodules, which may coalesce to give rise to larger lesions. Human papillomavirus (HPV), especially genotypes 13 and 32, have been associated and detected in the majority of FEH lesions. The clinical examination and social history often allow diagnosis, but histopathological examination of lesional tissue is usually required to confirm the exact diagnosis. FEH sometimes resolves spontaneously however, treatment is often indicated as a consequence of aesthetic effects or any interference with occlusion. There remains no specific therapy for FEH, although surgical removal, laser excision or possibly topical antiviral agents may be of benefit. There remains no evidence that FEH is potentially malignant.

  1. Lasers for median lobe hyperplasia.

    PubMed

    Muschter, R; Gilling, A P

    2001-08-01

    Laser treatment encompases a variety of techniques using different laser wavelengths, application systems, and surgical techniques to achieve contrasting tissue effects such as incision, resection, vaporization, or coagulation. Many studies have proven the clinical efficacy of the various laser techniques for the treatment of benign prostatiuc hyperplasia, including randomized studies versus transurethral prostatectomy (TURP). Recently, long-term follow-up of up to 5 years has demonstrated the durability of the results, although in some of the studies, retreatment rates were higher than after TURP. Median lobes were never seen as a contraindication for treatment in the laser based procedures. Technically, laser treatment techniques such as side-firing transurethral coagulation, contact- and free-beam laser vaporization, interstitial laser coagulation, and the holmium laser-based resection and enucleation are fully suitable for treatment of median lobes. Surprisingly, no studies focussing specifically on laser treatment of median lobes have been published.

  2. [Phytotherapy of benign prostatic hyperplasia].

    PubMed

    Bracher, F

    1997-01-01

    Phytopharmaceutical agents have been used for a long time in the treatment of symptomatic benign prostatic hyperplasia (BPH). However, until recently, it has been questioned whether phytotherapy is superior to a placebo treatment. In this article, the most widely used phytopharmaceutical agents, such as saw palmetto berry extracts, Radix urticae extracts, pumpkin seeds, pollen extracts and different phytosterols, are described. In addition, both in vitro and in vivo studies are discussed in an attempt to explain a possible mechanism of action. There are several new clinical studies which demonstrate a significant benefit compared with placebo treatment. Based on these results, the use of phytopharmaceutical agents for the treatment of mild to moderate symptomatic BPH seems to be well justified. So far, no significant inhibition of further prostate growth has been demonstrated. For this, a careful follow-up of the patients is necessary so as not to miss a deterioration and perhaps the need for an operation.

  3. Laser tonsillotomy in children with tonsillar hyperplasia.

    PubMed

    Baharudin, A; Shahid, H; Rhendra, M Z

    2006-08-01

    Tonsillectomy in children is performed on a regular basis in ENT. The indications are chronic tonsillitis, sleep apnea to deeper structures. The natural history of tonsillar hyperplasia is regression when a child is six years beyond. In children with bilateral tonsillar hyperplasia we studied the use of laser as an alternative procedure to reduce the bulk of the tonsillar mass. Children with symptoms of bilateral tonsillar hyperplasia underwent laser tonsillotomy. The tonsils were dissected using carbon dioxide (CO2) laser. The tonsillar bed was left untouched. Intraoperative and postoperative conditions were noted.

  4. Unitized regenerative fuel cell systems

    SciTech Connect

    Mitlitsky, F; Molter, T M; Myers, B; Weisberg, A H

    1998-09-10

    Energy storage systems with extremely high specific energy (>400 Wh/kg) have been designed that use lightweight pressure vessels to contain the gases generated by reversible (unitized) regenerative fuel cells (URFCs).[1] URFC systems are being designed and developed for a variety of applications, including high altitude long endurance (HALE) solar rechargeable aircraft (SRA), zero emission vehicles (ZEVs), hybrid energy storage/propulsion systems for spacecraft, energy storage for remote (off-grid) power sources, and peak shaving for on-grid applications.[1-10] Energy storage for HALE SRA was the original application for this set of innovations, and a prototype solar powered aircraft (Pathfinder-Plus) recently set another altitude record for all propeller-driven aircraft on August 6, 1998, when it flew to 80,285 feet (24.47 km).[11

  5. Unitized regenerative fuel cell system

    NASA Technical Reports Server (NTRS)

    Burke, Kenneth A. (Inventor)

    2008-01-01

    A Unitized Regenerative Fuel Cell system uses heat pipes to convey waste heat from the fuel cell stack to the reactant storage tanks. The storage tanks act as heat sinks/sources and as passive radiators of the waste heat from the fuel cell stack. During charge up, i.e., the electrolytic process, gases are conveyed to the reactant storage tanks by way of tubes that include dryers. Reactant gases moving through the dryers give up energy to the cold tanks, causing water vapor in with the gases to condense and freeze on the internal surfaces of the dryer. During operation in its fuel cell mode, the heat pipes convey waste heat from the fuel cell stack to the respective reactant storage tanks, thereby heating them such that the reactant gases, as they pass though the respective dryers on their way to the fuel cell stacks retrieve the water previously removed.

  6. [Regenerative medicine: history and perspectives].

    PubMed

    Okabayashi, Koji; Asashima, Makoto

    2008-05-01

    Regenerative medicine using stem cells is one of the most important topics today. Embryonic stem cells (ES cells) are useful in the studies of the differentiation of various cells or tissues for transplantation therapy, because of their pluripotency to differentiate into almost all types of cells in the body. However, it is controversial to use human ES cells, because it is necessary to sacrifice the life of human embryos for the establishment of these cells. Induced pluripotent stem cells (iPS cells) generated from somatic cells of patients are one of the alternative sources of human pluripotent stem cells while avoiding ethical problems. Epigenetic studies using iPS cells may be valuable to find the way to control cell differentiation more effectively.

  7. Variable ratio regenerative braking device

    DOEpatents

    Hoppie, Lyle O.

    1981-12-15

    Disclosed is a regenerative braking device (10) for an automotive vehicle. The device includes an energy storage assembly (12) having a plurality of rubber rollers (26, 28) mounted for rotation between an input shaft (36) and an output shaft (42), clutches (38, 46) and brakes (40, 48) associated with each shaft, and a continuously variable transmission (22) connectable to a vehicle drivetrain and to the input and output shafts by the respective clutches. The rubber rollers are torsionally stressed to accumulate energy from the vehicle when the input shaft is clutched to the transmission while the brake on the output shaft is applied, and are torsionally relaxed to deliver energy to the vehicle when the output shaft is clutched to the transmission while the brake on the input shaft is applied. The transmission ratio is varied to control the rate of energy accumulation and delivery for a given rotational speed of the vehicle drivetrain.

  8. Regenerative Electroless Etching of Silicon.

    PubMed

    Kolasinski, Kurt W; Gimbar, Nathan J; Yu, Haibo; Aindow, Mark; Mäkilä, Ermei; Salonen, Jarno

    2017-01-09

    Regenerative electroless etching (ReEtching), described herein for the first time, is a method of producing nanostructured semiconductors in which an oxidant (Ox1 ) is used as a catalytic agent to facilitate the reaction between a semiconductor and a second oxidant (Ox2 ) that would be unreactive in the primary reaction. Ox2 is used to regenerate Ox1 , which is capable of initiating etching by injecting holes into the semiconductor valence band. Therefore, the extent of reaction is controlled by the amount of Ox2 added, and the rate of reaction is controlled by the injection rate of Ox2 . This general strategy is demonstrated specifically for the production of highly luminescent, nanocrystalline porous Si from the reaction of V2 O5 in HF(aq) as Ox1 and H2 O2 (aq) as Ox2 with Si powder and wafers.

  9. Angiolymphoid Hyperplasia with Eosinophilia: A Case Report

    PubMed Central

    Esteves, Paola; Barbalho, Marcella; Lima, Tiago; Quintella, Leonardo; Niemeyer-Corbellini, João Paulo; Ramos-e-Silva, Marcia

    2015-01-01

    Angiolymphoid hyperplasia with eosinophilia is a rare disease considered as being a vascular malformation resulting from a subjacent arteriovenous shunt. It affects mostly the head of women between 20 and 40 years old and may present spontaneous involution. PMID:26120306

  10. Oxidative stress in benign prostate hyperplasia.

    PubMed

    Zabaiou, N; Mabed, D; Lobaccaro, J M; Lahouel, M

    2016-02-01

    To assess the status of oxidative stress in benign prostate hyperplasia, a very common disease in older men which constitutes a public health problem in Jijel, prostate tissues were obtained by transvesical adenomectomy from 10 men with benign prostate hyperplasia. We measured the cytosolic levels of malondialdehyde (MDA) and glutathione (GSH) and cytosolic enzyme activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione S-transferase. The development of benign prostate hyperplasia is accompanied by impaired oxidative status by increasing levels of MDA, depletion of GSH concentrations and a decrease in the activity of all the antioxidant enzymes studied. These results have allowed us to understand a part of the aetiology of benign prostate hyperplasia related to oxidative stress.

  11. Diffuse villous hyperplasia of choroid plexus.

    PubMed

    Iplikcioglu, A C; Bek, S; Gökduman, C A; Bikmaz, K; Cosar, M

    2006-06-01

    Diffuse villous hyperplasia of choroid plexus (DVHCP) is a rare condition which is characterized by the presence of diffuse enlargement of the entire choroid plexus throughout the length of the choroidal fissure and overproduction of CSF. The diagnosis of diffuse villous hyperplasia of choroid plexus can be established by the MR demonstration of diffusely large, contrast enhanced choroid plexus in the cases of overproduction hydrocephalus. Although some authors recommend choroid plexus excision or coagulation, ventriculo-atrial shunt insertion is a simple and effective treatment modality in cases of diffuse villous hyperplasia of the choroid plexus. In this report we present a case of diffuse villous hyperplasia of the choroid plexus and a short review of the literature. To our knowledge, in the CT and MRI era only 5 cases of DVHCP cases have been reported.

  12. Ancient history of congenital adrenal hyperplasia.

    PubMed

    New, Maria I

    2011-01-01

    Although there are many erudite reports on the history of endocrinology and endocrine disorders, the history of congenital adrenal hyperplasia has not been published. I have tried to review ancient as well as modern history of CAH.

  13. Sebaceous hyperplasia: systemic treatment with isotretinoin*

    PubMed Central

    Tagliolatto, Sandra; Santos, Octavio de Oliveira; Alchorne, Maurício Mota de Avelar; Enokihara, Mauro Yoshiaki

    2015-01-01

    The study aimed to verify the therapeutic action of isotretinoin in the treatment of sebaceous hyperplasia. During two months, 20 patients with sebaceous hyperplasia took isotretinoin at a dosage of 1mg/kg per day. Their skin lesions were counted and photographed before and after treatment and re-evaluated two years later. The average number of sebaceous hyperplasia lesions before treatment was 24 per patient. At the end of two months of therapy, the number of lesions decreased to 2 per patient. The statistically analyzed data showed a reduction in the number of lesions following isotretinoin use (p < 0.05). Two years after the end of the treatment, the average number of sebaceous hyperplasia lesions was 4 per patient. There were no severe side effects. Thus, the data analysis suggests that isotretinoin is a safe and effective drug for treating the disease under study. PMID:25830991

  14. Sebaceous hyperplasia: systemic treatment with isotretinoin.

    PubMed

    Tagliolatto, Sandra; Santos Neto, Octavio de Oliveira; Alchorne, Maurício Mota de Avelar; Enokihara, Mauro Yoshiaki

    2015-01-01

    The study aimed to verify the therapeutic action of isotretinoin in the treatment of sebaceous hyperplasia. During two months, 20 patients with sebaceous hyperplasia took isotretinoin at a dosage of 1mg/kg per day. Their skin lesions were counted and photographed before and after treatment and re-evaluated two years later. The average number of sebaceous hyperplasia lesions before treatment was 24 per patient. At the end of two months of therapy, the number of lesions decreased to 2 per patient. The statistically analyzed data showed a reduction in the number of lesions following isotretinoin use (p < 0.05). Two years after the end of the treatment, the average number of sebaceous hyperplasia lesions was 4 per patient. There were no severe side effects. Thus, the data analysis suggests that isotretinoin is a safe and effective drug for treating the disease under study.

  15. Modeling regenerative braking and storage for vehicles

    SciTech Connect

    Wicks, F.; Donnelly, K.

    1997-12-31

    The fuel savings benefits of regenerative braking and storage for vehicles are often described but not quantified. For example, the federal government and automobile manufacturers are sponsoring a Program for a New Generation of Vehicles (PGNV) with a goal of obtaining a performance of 80 mpg in a family size car. It is typically suggested that such a vehicle will be a hybrid engine and electric drive with regenerative braking. The authors note that while regenerative braking has the potential of saving fuel, it may also do more harm than good as a result of additional weight, less than ideal charge/discharge efficiency on the batteries or storage flywheels and the limited portion of the entire driving cycle when regenerative braking can be utilized. The authors also noted that if regenerative braking can have a net benefit, it would be on a heavy vehicle such as a municipal bus because of the frequent stop and go requirements for both traffic light and passengers. Thus the authors initiated a study of regenerative braking on such a vehicle. The resulting analysis presented in this paper includes data following municipal buses to define the driving cycle, modeling the bus power requirements from weight, aerodynamics and rolling resistance, and then calculating the fuel saving that could result from an ideal regenerative braking system.

  16. An uncommon focal epithelial hyperplasia manifestation.

    PubMed

    dos Santos-Pinto, Lourdes; Giro, Elisa Maria Aparecida; Pansani, Cyneu Aguiar; Ferrari, Junia; Massucato, Elaine Maria Sgavioli; Spolidório, Luis Carlos

    2009-01-01

    Focal epithelial hyperplasia is a rare, contagious disease associated with infection of the oral mucosa by human papillomavirus types 13 or 32, characterized by multiple soft papules of the same color as the adjacent normal mucosa. It mainly affects the lower lip, buccal mucosa, and tongue. The purpose of this case report was to describe a rare verrucal lesion located in the upper gingiva that was clinically and histologically consistent with focal epithelial hyperplasia.

  17. Stem cell research and regenerative medicine in 2014: first year of regenerative medicine in Japan.

    PubMed

    Okano, Hideyuki

    2014-09-15

    It is my great pleasure to announce that we were able to publish the Japan Issue in Stem Cells and Development, especially in this year 2014. This year, 2014, is said to be the First Year of Regenerative Medicine in Japan. This movement is likely to be based on the establishment of a new law system regarding regenerative medicine (an Act for Ensuring the Safety of Regenerative Medicine or the so-called Regenerative Medicine Law) and the partial revision of the Pharmaceutical Affairs Law (PAL). Both laws will come into effect in 2014 in this country. These new law systems are expected to have a great impact on the facilitation of R&D related to regenerative medicine and stem cell biology. In the present Japan Issue, some excellent stem cell research in this country will be introduced to celebrate the First Year of Regenerative Medicine in Japan.

  18. Regenerative medicine: a primer for paediatricians.

    PubMed

    Polak, Dame Julia M

    2009-11-01

    Regenerative medicine is a multidisciplinary field concerned with the replacement, repair or restoration of injured tissues. Cell therapy and tissue engineering are part of the broader remit of regenerative medicine. The ultimate aim is to provide safe and efficient therapies for a large number of clinical conditions. Novel regenerative therapies are already in use in initial clinical trials. The main components of regenerative medicine are cells and specially designed materials. A vast variety of cells types are currently used including: adult and stem cells. Equally a large number of natural and man-made materials have been investigated. Despite of considerable advances many challenges lie ahead. These are summarised in this review article. The field is slowly maturing and the initial unhelpful hype has been replaced by a more measured, mature and realistic outlook.

  19. Regenerative medicine applications in combat casualty care.

    PubMed

    Fleming, Mark E; Bharmal, Husain; Valerio, Ian

    2014-03-01

    The purpose of this report is to describe regenerative medicine applications in the management of complex injuries sustained by service members injured in support of the wars in Afghanistan and Iraq. Improvements in body armor, resuscitative techniques and faster transport have translated into increased patient survivability and more complex wounds. Combat-related blast injuries have resulted in multiple extremity injuries, significant tissue loss and amputations. Due to the limited availability and morbidity associated with autologous tissue donor sites, the introduction of regenerative medicine has been critical in managing war extremity injuries with composite massive tissue loss. Through case reports and clinical images, this report reviews the application of regenerative medicine modalities employed to manage combat-related injuries. It illustrates that the novel use of hybrid reconstructions combining traditional and regenerative medicine approaches are an effective tool in managing wounds. Lessons learned can be adapted to civilian care.

  20. Regenerative rotary displacer Stirling engine

    SciTech Connect

    Isshiki, Naotsugu; Watanabe, Hiroichi; Raggi, L.; Isshiki, Seita; Hirata, Koichi

    1996-12-31

    A few rotary displacer Stirling engines in which the displacer has one gas pocket space at one side and rotates in a main enclosed cylinder, which is heated from one side and cooled from opposite side without any regenerator, have been studied for some time by the authors. The authors tried to improve this engine by equipping it with a regenerator, because without a regenerator, pressure oscillation and efficiency are too small. Here, several types of regenerative rotary displacer piston Stirling engines are proposed. One is the contra-rotating tandem two disc type displacer engine using axial heat conduction through side walls or by heat pipes and another is a single disc type with circulating fluid regenerator or heat pipes. Stirling engines of this new rotary displacer type are thought to attain high speed. Here, experimental results of the original rotary displacer Stirling engine without a regenerator, and one contra-rotating tandem displacer engine with side wall regenerator by axial heat conduction are reported accompanied with a discussion of the results.

  1. A regenerative elastocaloric heat pump

    NASA Astrophysics Data System (ADS)

    Tušek, Jaka; Engelbrecht, Kurt; Eriksen, Dan; Dall'Olio, Stefano; Tušek, Janez; Pryds, Nini

    2016-10-01

    A large fraction of global energy use is for refrigeration and air-conditioning, which could be decarbonized if efficient renewable energy technologies could be found. Vapour-compression technology remains the most widely used system to move heat up the temperature scale after more than 100 years; however, caloric-based technologies (those using the magnetocaloric, electrocaloric, barocaloric or elastocaloric effect) have recently shown a significant potential as alternatives to replace this technology due to high efficiency and the use of green solid-state refrigerants. Here, we report a regenerative elastocaloric heat pump that exhibits a temperature span of 15.3 K on the water side with a corresponding specific heating power up to 800 W kg-1 and maximum COP (coefficient-of-performance) values of up to 7. The efficiency and specific heating power of this device exceeds those of other devices based on caloric effects. These results open up the possibility of using the elastocaloric effect in various cooling and heat-pumping applications.

  2. High power regenerative laser amplifier

    DOEpatents

    Miller, J.L.; Hackel, L.A.; Dane, C.B.; Zapata, L.E.

    1994-02-08

    A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse. 7 figures.

  3. High power regenerative laser amplifier

    DOEpatents

    Miller, John L.; Hackel, Lloyd A.; Dane, Clifford B.; Zapata, Luis E.

    1994-01-01

    A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse.

  4. Staged regenerative sorption heat pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor)

    1995-01-01

    A regenerative adsorbent heat pump process and system for cooling and heating a space. A sorbent is confined in a plurality of compressors of which at least four are first stage and at least four are second stage. The first stage operates over a first pressure region and the second stage over a second pressure region which is higher than the first. Sorbate from the first stage enters the second stage. The sorbate loop includes a condenser, expansion valve, evaporator and the compressors. A single sorbate loop can be employed for single-temperature-control such as air conditioning and heating. Two sorbate loops can be used for two-temperature-control as in a refrigerator and freezer. The evaporator temperatures control the freezer and refrigerator temperatures. Alternatively the refrigerator temperature can be cooled by the freezer with one sorbate loop. A heat transfer fluid is circulated in a closed loop which includes a radiator and the compressors. Low temperature heat is exhausted by the radiator. High temperature heat is added to the heat transfer fluid entering the compressors which are desorbing vapor. Heat is transferred from compressors which are sorbing vapor to the heat transfer fluid, and from the heat transfer fluid to the compressors which are desorbing vapor. Each compressor is subjected to the following phases, heating to its highest temperature, cooling down from its highest temperature, cooling to its lowest temperature, and warming up from its lowest temperature. The phases are repeated to complete a cycle and regenerate heat.

  5. Clinical imaging in regenerative medicine

    PubMed Central

    Naumova, Anna V; Modo, Michel; Moore, Anna; Murry, Charles E; Frank, Joseph A

    2014-01-01

    In regenerative medicine, clinical imaging is indispensable for characterizing damaged tissue and for measuring the safety and efficacy of therapy. However, the ability to track the fate and function of transplanted cells with current technologies is limited. Exogenous contrast labels such as nanoparticles give a strong signal in the short term but are unreliable long term. Genetically encoded labels are good both short- and long-term in animals, but in the human setting they raise regulatory issues related to the safety of genomic integration and potential immunogenicity of reporter proteins. Imaging studies in brain, heart and islets share a common set of challenges, including developing novel labeling approaches to improve detection thresholds and early delineation of toxicity and function. Key areas for future research include addressing safety concerns associated with genetic labels and developing methods to follow cell survival, differentiation and integration with host tissue. Imaging may bridge the gap between cell therapies and health outcomes by elucidating mechanisms of action through longitudinal monitoring. PMID:25093889

  6. Regenerative fuel cell engineering - FY99

    SciTech Connect

    Michael A. Inbody; Rodney L. Borup; James C. Hedstrom; Jose Tafoya; Byron Morton; Lois Zook; Nicholas E. Vanderborgh

    2000-01-01

    The authors report the work conducted by the ESA-EPE Fuel Cell Engineering Team at Los Alamos National Laboratory during FY99 on regenerative fuel cell system engineering. The work was focused on the evaluation of regenerative fuel cell system components obtained through the RAFCO program. These components included a 5 kW PEM electrolyzer, a two-cell regenerative fuel cell stack, and samples of the electrolyzer membrane, anode, and cathode. The samples of the electrolyzer membrane, anode, and cathode were analyzed to determine their structure and operating characteristics. Tests were conducted on the two-cell regenerative fuel cell stack to characterize its operation as an electrolyzer and as a fuel cell. The 5 kW PEM electrolyzer was tested in the Regenerative Fuel Cell System Test Facility. These tests served to characterize the operation of the electrolyzer and, also, to verify the operation of the newly completed test facility. Future directions for this work in regenerative fuel cell systems are discussed.

  7. Current overview on challenges in regenerative endodontics

    PubMed Central

    Bansal, Ramta; Jain, Aditya; Mittal, Sunandan

    2015-01-01

    Introduction: Regenerative endodontics provides hope of converting the non-vital tooth into vital once again. It focuses on substituting traumatized and pathological pulp with functional pulp tissue. Current regenerative procedures successfully produce root development but still fail to re-establish real pulp tissue and give unpredictable results. There are several drawbacks that need to be addressed to improve the quality and efficiency of the treatment. Aim: The aim of this review article is to discuss major priorities that ought to be dealt before applications of regenerative endodontics flourish the clinical practice. Materials and Methods: A web-based research on MEDLINE was done using filter terms Review, published in the last 10 years and Dental journals. Keywords used for research were “regenerative endodontics,” “dental stem cells,” “growth factor regeneration,” “scaffolds,” and “challenges in regeneration.” This review article screened about 150 articles and then the relevant information was compiled. Results: Inspite of the impressive growth in regenerative endodontic field, there are certain loopholes in the existing treatment protocols that might sometimes result in undesired and unpredictable outcomes. Conclusion: Considerable research and development efforts are required to improve and update existing regenerative endodontic strategies to make it an effective, safe, and biological mode to save teeth. PMID:25657518

  8. Pseudocarcinomatous hyperplasia of the urinary bladder.

    PubMed

    Wu, Angela

    2014-10-01

    We review the morphology and differential diagnoses of pseudocarcinomatous hyperplasia of the bladder, using a study case to illustrate the discussion. Pseudocarcinomatous hyperplasia is a rare, reactive response to an ischemic insult, classically to radiation therapy, and consists of proliferative, pseudoinfiltrative urothelial nests within the stroma. The presence of background radiation therapy-related changes, such as numerous dilated thrombosed vessels, reactive-appearing endothelial and stromal cells, edema, and hemorrhage, can provide clues to the diagnosis. The main differential diagnoses include invasive urothelial carcinoma and the nested variant of urothelial carcinoma; morphologic features, such as the presence or absence of background therapy-related changes and the architecture and the cytologic atypia of the nests, can help distinguish between pseudocarcinomatous hyperplasia and urothelial carcinoma.

  9. Intrathyroidal parathyroid hyperplasia in tertiary hyperparathyroidism

    PubMed Central

    Kim, Byung Seup; Ryu, Han Suk; Kang, Kyung Ho; Park, Sung Jun

    2013-01-01

    We report herein a case of intrathyroidal parathyroid hyperplasia in a patient with tertiary hyperparathyroidism. The patient was recommended for parathyroidectomy due to sustained hypercalcemia after kidney transplantation. Preoperative radiologic evaluations showed a benign-looking thyroid mass and three enlarged parathyroid glands. Intraoperative intact parathyroid hormone (iPTH) level and frozen biopsy results indicated a missed parathyroid gland after immediate subtotal parathyroidectomy. Then, a secondary partial resection of thyroid including the thyroid nodule was performed. An excised intrathyroid nodule was diagnosed to be parathyroid hyperplasia by frozen biopsy, and intraoperative iPTH level abruptly decreased. A benign-looking thyroidal mass in patients with secondary or tertiary hyperparathyroidism should be carefully evaluated considering the possibility of an intrathyroidal parathyroid hyperplasia. PMID:24964443

  10. [Modern pharmacotherapy of benign prostatic hyperplasia].

    PubMed

    Krysiak, Robert; Okopień, Bogusław; Szkróbka, Witold; Herman, Zbigniew Stanisław

    2005-11-01

    Benign prostatic hyperplasia is the most common medical problem affecting elderly men throughout the world. With increasing awareness of health issues amongst males, the morbidity caused by this disease is not longer being accepted as just part of growing old. Until about 10 years ago, surgery was the only effective treatment for symptomatic benign prostatic hyperplasia. Now, many men suffering from this disorder may be effectively treated with a medical therapy. This article provides an overview of the efficacy and safety of 5alpha-reductase inhibitors, alpha1-adrenoceptor antagonists and herbal remedies, putting special emphasis on the current place of these agents in the modem therapy of benign prostatic hyperplasia. Wherever possible, our opinion is based on the detailed analysis of the results of available clinical trials.

  11. Outcome of congenital adrenal hyperplasia.

    PubMed

    Kuhnle, U; Bullinger, M

    1997-09-01

    In congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, affected girls are born with ambiguous genitalia due to increased secretion of androgens in utero by the defective adrenal gland. Even though it is generally accepted that there are differences between male and female brain development, determining factors have been difficult to identify. Girls with CAH have frequently been studied to evaluate the impact of prenatal androgen exposure on psychological, psychosocial, and psychosexual development, and impairments in various areas have been identified. However, there is no comprehensive study available regarding the outcome of this chronic disorder in adult life. We studied the quality of life in women with CAH, with particular emphasis on how they cope with genital malformations, genital operations, and chronic disease as well as lifelong medication. The patients filled out questionnaires covering their physical state, psychological well-being, social relationships, and functional capacity, as well as questionnaires on psychosexual identification and psychosocial integration. The results were evaluated using a computerized statistical program for social studies. Out of a total of 94 patients above 18 years of age, 45 agreed to participate and were compared to 46 healthy, age-matched controls. Age at diagnosis was 2. 31 +/- 1.55 years and 38% suffered from the simple-virilizing, 45% from the salt-wasting, and 17.0% from the late-onset form of CAH. About one-third of patients had Prader stage 3 or 4 genital virilization. While the overall quality of life did not differ significantly, CAH patients were more often single (47.8% vs. 66.7%) and fewer of them had children (22.2% vs. 38.6%) compared to controls. Significant impairments were found in regard to body image and attitudes toward sexuality, but there was no increased homosexual preference. The women were successful in adjusting to illness and receiving social support. It is speculated that

  12. Extensive Focal Epithelial Hyperplasia: A Case Report.

    PubMed

    Mansouri, Zahra; Bakhtiari, Sedigheh; Noormohamadi, Robab

    2015-01-01

    Focal epithelial hyperplasia (FEH) or Heck's disease is a rare viral infection of the oral mucosa caused by human papilloma virus especially subtypes 13 or 32. The frequency of this disease varies widely from one geographic region and ethnic groups to another. This paper reports an Iranian case of extensive focal epithelial hyperplasia. A 35-year-old man with FEH is described, in whom the lesions had persisted for more than 25 years. The lesion was diagnosed according to both clinical and histopathological features. Dental practitioner should be aware of these types of lesions and histopathological examination together and a careful clinical observation should be carried out for a definitive diagnosis.

  13. Regenerative medicine: Current therapies and future directions

    PubMed Central

    Mao, Angelo S.; Mooney, David J.

    2015-01-01

    Organ and tissue loss through disease and injury motivate the development of therapies that can regenerate tissues and decrease reliance on transplantations. Regenerative medicine, an interdisciplinary field that applies engineering and life science principles to promote regeneration, can potentially restore diseased and injured tissues and whole organs. Since the inception of the field several decades ago, a number of regenerative medicine therapies, including those designed for wound healing and orthopedics applications, have received Food and Drug Administration (FDA) approval and are now commercially available. These therapies and other regenerative medicine approaches currently being studied in preclinical and clinical settings will be covered in this review. Specifically, developments in fabricating sophisticated grafts and tissue mimics and technologies for integrating grafts with host vasculature will be discussed. Enhancing the intrinsic regenerative capacity of the host by altering its environment, whether with cell injections or immune modulation, will be addressed, as well as methods for exploiting recently developed cell sources. Finally, we propose directions for current and future regenerative medicine therapies. PMID:26598661

  14. Functional imaging for regenerative medicine.

    PubMed

    Leahy, Martin; Thompson, Kerry; Zafar, Haroon; Alexandrov, Sergey; Foley, Mark; O'Flatharta, Cathal; Dockery, Peter

    2016-04-19

    In vivo imaging is a platform technology with the power to put function in its natural structural context. With the drive to translate stem cell therapies into pre-clinical and clinical trials, early selection of the right imaging techniques is paramount to success. There are many instances in regenerative medicine where the biological, biochemical, and biomechanical mechanisms behind the proposed function of stem cell therapies can be elucidated by appropriate imaging. Imaging techniques can be divided according to whether labels are used and as to whether the imaging can be done in vivo. In vivo human imaging places additional restrictions on the imaging tools that can be used. Microscopies and nanoscopies, especially those requiring fluorescent markers, have made an extraordinary impact on discovery at the molecular and cellular level, but due to their very limited ability to focus in the scattering tissues encountered for in vivo applications they are largely confined to superficial imaging applications in research laboratories. Nanoscopy, which has tremendous benefits in resolution, is limited to the near-field (e.g. near-field scanning optical microscope (NSNOM)) or to very high light intensity (e.g. stimulated emission depletion (STED)) or to slow stochastic events (photo-activated localization microscopy (PALM) and stochastic optical reconstruction microscopy (STORM)). In all cases, nanoscopy is limited to very superficial applications. Imaging depth may be increased using multiphoton or coherence gating tricks. Scattering dominates the limitation on imaging depth in most tissues and this can be mitigated by the application of optical clearing techniques that can impose mild (e.g. topical application of glycerol) or severe (e.g. CLARITY) changes to the tissue to be imaged. Progression of therapies through to clinical trials requires some thought as to the imaging and sensing modalities that should be used. Smoother progression is facilitated by the use of

  15. Cardiovascular Regenerative Technologies: Update and Future Outlook

    PubMed Central

    Mallone, Anna; Weber, Benedikt; Hoerstrup, Simon P.

    2016-01-01

    In the effort of improving treatment for cardiovascular disease (CVD), scientists struggle with the lack of the regenerative capacities of finally differentiated cardiovascular tissues. In this context, the advancements in regenerative medicine contributed to the development of cell-based therapies as well as macro- and micro-scale tissue-engineering technologies. The current experimental approaches focus on different regenerative strategies including a broad spectrum of techniques such as paracrine-based stimulation of autologous cardiac stem cells, mesenchymal cell injections, 3D microtissue culture techniques and vascular tissue-engineering methods. These potential next-generation strategies are leading the way to a revolution in addressing CVD, and numerous studies are now undertaken to assess their therapeutic value. With this review, we provide an update on the current research directions, on their major challenges, limitations, and achievements. PMID:27721705

  16. Therapeutic potential of nanoceria in regenerative medicine

    SciTech Connect

    Das, Soumen; Chigurupati, Srinivasulu; Dowding, Janet; Munusamy, Prabhakaran; Baer, Donald R.; McGinnis, James F.; Mattson, Mark P.; Self, William; Seal, Sudipta

    2014-11-01

    Tissue engineering and regenerative medicine aim to achieve functional restoration of tissue or cells damaged through disease, aging or trauma. Advancement of tissue engineering requires innovation in the field of 3D scaffolding, and functionalization with bioactive molecules. Nanotechnology offers advanced materials with patterned nano-morphologies for cell growth and different molecular substrates which can support cell survival and functions. Cerium oxide nanoparticles (nanoceria) can control intracellular as well as extracellular reactive oxygen and nitrogen species. Recent findings suggest that nanoceria can enhance long-term cell survival, enable cell migration and proliferation, and promote stem cell differentiation. Moreover, the self-regenerative property of nanoceria permits a small dose to remain catalytically active for extended time. This review summarizes the possibilities and applications of nanoceria in the field of tissue engineering and regenerative medicine.

  17. Combined hydraulic and regenerative braking system

    DOEpatents

    Venkataperumal, R.R.; Mericle, G.E.

    1979-08-09

    A combined hydraulic and regenerative braking system and method for an electric vehicle is disclosed. The braking system is responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

  18. Combined hydraulic and regenerative braking system

    SciTech Connect

    Venkataperumal, Rama R.; Mericle, Gerald E.

    1981-06-02

    A combined hydraulic and regenerative braking system and method for an electric vehicle, with the braking system being responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

  19. Intravascular papillary endothelial hyperplasia of the foot.

    PubMed

    Cisco, R W; McCormac, R M

    1994-01-01

    Intravascular papillary endothelial hyperplasia is a rare benign reactive lesion usually found in thrombosed subcutaneous blood vessels. The lesion resembles malignant angiosarcoma clinically and histopathologically, and must be diagnosed correctly to avoid inappropriate treatment. The following is a case presentation involving the foot.

  20. Multifocal epithelial hyperplasia. Report of nine cases.

    PubMed

    Ledesma-Montes, Constantino; Vega-Memije, Elisa; Garcés-Ortíz, Maricela; Cardiel-Nieves, Maritza; Juárez-Luna, Claudia

    2005-01-01

    Multifocal epithelial hyperplasia (MEH) is also known as focal epithelial hyperplasia, Heck's disease or multifocal papillomavirus-induced epithelial hyperplasia. It is characterised by the presence of multiple lesions in the oral mucosa of children and it has been associated with the presence of the human papillomavirus. The aim of this study was to determine the clinico-pathological features of the cases diagnosed as MEH in the Service of Dermatology of the Hospital Manuel Gea González (SDHMGG). The files of the SDHMGG were reviewed and all cases diagnosed as MEH were retrieved. Nine MEH cases were found. Most of the patients were 20 year-old or younger (67%) and females were more commonly affected (78%). All patients presented multiple lesions and always, close relatives with similar lesions were found. Lesions were located most commonly in the buccal mucosa, lower lip and commissures. MEH is a soft tissue intraoral condition that needs treatment solely of the traumatised lesions or those with cosmetic problems. Remaining lesions will disappear with the age of the patients. It is suggested that this entity should be named multifocal epithelial hyperplasia since this name describes better the clinico-pathological and microscopic features of the disease.

  1. [Focal epithelial hyperplasia. An unusual clinical aspect].

    PubMed

    Bodokh, I; Lacour, J P; Rainero, C; Orth, G; Perrin, C; Hoffman, P; Santini, J; Ortonne, J P

    1993-01-01

    We report a case of focal epithelial hyperplasia in a child born in France of Algerian parents. The clinical appearance was unusual in that certain lesions were verrucous and pediculate. A virological study revealed the presence of papillomavirus 32, one of the two types of HPV specifically associated with this entity.

  2. Pseudoepitheliomatous Hyperplasia in Oral Lesions: A Review

    PubMed Central

    Nayak, Vaidhehi Narayan; Uma, K; Girish, H C; Murgod, Sanjay; Shyamala, K; Naik, Ranajit B

    2015-01-01

    Pseudoepitheliomatous hyperplasia (PEH) is a histopathological reaction pattern to various stimuli, which includes trauma, infection, inflammation, neoplasia. It is seen as tongue like epithelial proliferation invading the connective tissue and should not be mistaken for squamous cell carcinoma (SCC). This review enlists oral lesions which exhibit PEH with a note on how to differentiate SCC from PEH. PMID:26435636

  3. Regenerative therapy: a periodontal-endodontic perspective.

    PubMed

    Kinaia, Bassam Michael; Chogle, Sami M A; Kinaia, Atheel M; Goodis, Harold E

    2012-07-01

    Periodontal and endodontic diseases are inflammatory responses leading to periodontal and pulpal tissue loss. Regenerative therapies aim to restore the lost structures to vitality and function. Various materials and treatments methods have been used such as bone grafts, guided tissue regeneration, enamel matrix derivatives, growth and differentiation factors, and stem cells. Although the current materials and methods demonstrated adequate clinical results, true and complete biological tissue regeneration is not yet attainable. The current article reviews chronologically the materials and methods used in periodontal and endodontic regeneration highlighting their clinical success and shortcomings, and discussing future directions in regenerative therapy.

  4. Improved Regenerative Sorbent-Compressor Refrigerator

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    1992-01-01

    Conceptual regenerative sorbent-compressor refrigerator attains regeneration efficiency and, therefore, overall power efficiency and performance greater than conventional refrigerators. Includes two fluid loops. In one, CH2FCF3 (R134a) ciculates by physical adsorption and desorption in four activated-charcoal sorption compressors. In other, liquid or gas coolant circulated by pump. Wave of regenerative heating and cooling propagates cyclically like peristatic wave among sorption compressors and associated heat exchangers. Powered by electricity, oil, gas, solar heat, or waste heat. Used as air conditioners, refrigerators, and heat pumps in industrial, home, and automotive applications.

  5. WIDE BAND REGENERATIVE FREQUENCY DIVIDER AND MULTIPLIER

    DOEpatents

    Laine, E.F.

    1959-11-17

    A regenerative frequency divider and multiplier having wide band input characteristics is presented. The circuit produces output oscillations having frequencies related by a fixed ratio to input oscillations over a wide band of frequencies. In accomplishing this end, the divider-multiplier includes a wide band input circuit coupled by mixer means to a wide band output circuit having a pass band related by a fixed ratio to that of the input circuit. A regenerative feedback circuit derives a fixed frequency ratio feedback signal from the output circuit and applies same to the mixer means in proper phase relation to sustain fixed frequency ratio oscillations in the output circuit.

  6. Regenerative medicine: does Erythropoietin have a role?

    PubMed

    Buemi, Michele; Lacquaniti, Antonio; Maricchiolo, Giulia; Bolignano, Davide; Campo, Susanna; Cernaro, Valeria; Sturiale, Alessio; Grasso, Giovanni; Buemi, Antoine; Allegra, Alessandro; Donato, Valentina; Genovese, Lucrezia

    2009-01-01

    Regenerative Medicine, a recent new medical domain, aims to develop new therapies through the stimulation of natural regenerative processes also in human beings. In this field, Erythropoietin (EPO) represents a significant subject of research. Several studies allow the assertion that EPO, in different concentrations, has protective effects mainly on the central nervous system, cardiovascular system and renal tissue. This action is carried out through one of few regenerative activities of human beings: angiogenesis. This mechanism, which involves endothelial stem cells and VEGF (Vascular Endothelial Growth Factor), has been experimentally demonstrated with Recombinant human erythropoietin (rHuEPO) and Darbepoetin, a long-acting EPO derivate. Furthermore, the demonstration of a cardiac production of EPO in Fugu rubripes and in Zebrafish has led cardiologists to "discover" Erythropoietin, postulating a hypothetical role in treatment of cardiovascular disease for this hormone. This is some of the experimental evidence which demonstrates that EPO can be in reason considered an important element of research of Regenerative Medicine and put in the network of drugs able to regenerate tissues and organs.

  7. Simulations of the LANL regenerative amplifier FEL

    SciTech Connect

    Kesselring, M.; Colson, W.B.; Wong, R.K.; Sheffield, R.L.

    1997-08-01

    The LANL regenerative amplifier FEL is designed to produce an average output power of 1 kW. Simulations study the transverse effects due to guiding by the intense electron beam and feedback. These simulations coupled with experimental measurements can be used to improve future high-power FEL designs.

  8. Regenerative fuel cells for space applications

    NASA Technical Reports Server (NTRS)

    Appleby, A. John

    1987-01-01

    After several years of development of the regenerative fuel cell (RFC) as the electrochemical storage system to be carried by the future space station, the official stance has now been adopted that nickel hydrogen batteries would be a better system choice. RFCs are compared with nickel hydrogen and other battery systems for space platform applications.

  9. Regenerative Studies: College Community and Community College.

    ERIC Educational Resources Information Center

    Woltz, Mary G.

    This case study applies principles derived from the Center for Regenerative Studies (CRS) to a community college in North Carolina. CRS, on the campus of California State Polytechnic Institute (California), is dedicated to the education, demonstration, and research of degenerative systems in the areas of shelter, food production, energy, water and…

  10. Applications of regenerative medicine in organ transplantation

    PubMed Central

    Jain, Aditya; Bansal, Ramta

    2015-01-01

    A worldwide shortage of organs for clinical implantation establishes the need to bring forward and test new technologies that will help in solving the problem. The concepts of regenerative medicine hold the potential for augmenting organ function or repairing damaged organ or allowing regeneration of deteriorated organs and tissue. Researchers are exploring possible regenerative medicine applications in organ transplantation so that coming together of the two fields can benefit each other. The present review discusses the strategies that are being implemented to regenerate or bio-engineer human organs for clinical purposes. It also highlights the limitations of the regenerative medicine that needs to be addressed to explore full potential of the field. A web-based research on MEDLINE was done using keywords “regenerative medicine,” “tissue-engineering,” “bio-engineered organs,” “decellularized scaffold” and “three-dimensional printing.” This review screened about 170 articles to get the desired knowledge update. PMID:26229352

  11. Mesenchymal stem cells, aging and regenerative medicine

    PubMed Central

    Raggi, Chiara; Berardi, Anna C.

    2012-01-01

    Summary Tissue maintenance and regeneration is dependent on stem cells and increasing evidence has shown to decline with age. Stem cell based-aging is thought to influence therapeutic efficacy. Mesenchymal stromal cells (MSCs) are involved in tissue regeneration. Here, we discuss the effects of age-related changes on MSC properties considering their possible use in research or regenerative medicine. PMID:23738303

  12. Regenerative nanomedicine: current perspectives and future directions

    PubMed Central

    Chaudhury, Koel; Kumar, Vishu; Kandasamy, Jayaprakash; RoyChoudhury, Sourav

    2014-01-01

    Nanotechnology has considerably accelerated the growth of regenerative medicine in recent years. Application of nanotechnology in regenerative medicine has revolutionized the designing of grafts and scaffolds which has resulted in new grafts/scaffold systems having significantly enhanced cellular and tissue regenerative properties. Since the cell–cell and cell-matrix interaction in biological systems takes place at the nanoscale level, the application of nanotechnology gives an edge in modifying the cellular function and/or matrix function in a more desired way to mimic the native tissue/organ. In this review, we focus on the nanotechnology-based recent advances and trends in regenerative medicine and discussed under individual organ systems including bone, cartilage, nerve, skin, teeth, myocardium, liver and eye. Recent studies that are related to the design of various types of nanostructured scaffolds and incorporation of nanomaterials into the matrices are reported. We have also documented reports where these materials and matrices have been compared for their better biocompatibility and efficacy in supporting the damaged tissue. In addition to the recent developments, future directions and possible challenges in translating the findings from bench to bedside are outlined. PMID:25214780

  13. Congenital adrenal hyperplasia with cholestatic jaundice.

    PubMed

    Ali, Nisreen Feroz; Zafar, Farhana; Bangash, Areeb Sohail; Malik, Abdul; Mohammedi, Karimunnisa

    2014-01-01

    Congenital Adrenal Hyperplasia describes a group of autosomal recessive disorders characterized by a decrease in Cortisol production. 11 beta hydroxylase deficiencies is the second most common form. However, its presentation with cholestatic jaundice is extremely rare. We present a case of a 29-day-old infant who came to us with unusual dark complexion, persistent jaundice, and electrolyte imbalance. On investigation he was diagnosed as a case of congenital adrenal hyperplasia. Treatment with hydrocortisone and fludrocortisone cleared his jaundice and complexion with subsequent improvement in electrolytes. The aim of this report is to illustrate an unusual presentation of CAH with Cholestatic jaundice. This is the first case to be reported from Pakistan. The case outlines the difficult workup that was encountered in the diagnosis and management of the patient.

  14. Extensive Focal Epithelial Hyperplasia: A Case Report

    PubMed Central

    Mansouri, Zahra; Bakhtiari, Sedigheh; Noormohamadi, Robab

    2015-01-01

    Focal epithelial hyperplasia (FEH) or Heck’s disease is a rare viral infection of the oral mucosa caused by human papilloma virus especially subtypes 13 or 32. The frequency of this disease varies widely from one geographic region and ethnic groups to another. This paper reports an Iranian case of extensive focal epithelial hyperplasia. A 35-year-old man with FEH is described, in whom the lesions had persisted for more than 25 years. The lesion was diagnosed according to both clinical and histopathological features. Dental practitioner should be aware of these types of lesions and histopathological examination together and a careful clinical observation should be carried out for a definitive diagnosis. PMID:26351501

  15. Myocardial hypertrophy induces carotid body hyperplasia.

    PubMed

    Sivridis, Efthimios; Pavlidis, Pavlos; Fiska, Aliki; Pitsiava, Dimitra; Giatromanolaki, Alexandra

    2011-01-01

    The carotid bodies tend to enlarge after long-standing cardiopulmonary disease. Our objective was to investigate whether cardiac hypertrophy is associated with carotid body hyperplasia. Fifteen autopsy cases with combined left and right ventricular hypertrophy were examined and compared with two control groups (16 cases). The study involved a meticulous dissection of carotid bifurcations, thin serial sections, and morphometric analysis of carotid body volume and cell types (progenitor, dark, light, and sustentacular). There was a significant increase in sustentacular cells in all individuals with cardiac hypertrophy, which was not drug-induced, and accompanied by a similar increase in carotid body volume. Dark or light cell accumulation was detected focally and only in three instances. It appears that the generalized sustentacular cell hyperplasia is the result of long-standing hypoxia, while a superimposed focal prominence of dark or light cells may be proliferative or metaplastic in nature and attributed to short-term hypoxia.

  16. Lymphoid papillary hyperplasia of the palatine tonsils.

    PubMed

    Carrillo-Farga, J; Abbud-Neme, F; Deutsch, E

    1983-09-01

    A rare case of papillary hyperplasia of the palatine tonsils is reported in a 9-year-old girl who presented with pharyngeal obstruction. The obstruction was due to the bilateral enlargement of the palatine tonsils with a papillary surface configuration so atypical that a diagnosis of malignant neoplasm was clinically considered. Histopathological study showed a peculiar form of lymphoid hyperplasia. No other members of the family were affected. As far as we know, this is the only case reported in recent years in an Occidental patient although a few similar cases have been reported from Japan. The importance of recognizing this peculiar abnormality rests in the fact that in spite of the clinical features simulating a cancer or multiple epithelial papillomas, the process is benign, probably non-neoplastic, and easily cured by bilateral tonsillectomy.

  17. Unilateral condylar hyperplasia: a treatment strategy.

    PubMed

    Ferreira, Sabrina; da Silva Fabris, André Luis; Ferreira, Gabriel Ramalho; Faverani, Leonardo Perez; Francisconi, Giovanna Barbosa; Souza, Francisley Avila; Garcia, Idelmo Rangel

    2014-05-01

    Condylar hyperplasia (CH) is a pathologic condition that causes overdevelopment of the condylar head and neck as well as the mandible. Slowly progressive unilateral enlargement of the head and the neck of the condyle causes crossbite malocclusion, facial asymmetry, and shifting of the midpoint of the chin to the unaffected side. The etiology and the pathogenesis of CH remain uncertain. The diagnosis is made by clinical and radiologic examinations and bone scintigraph. A difference in uptake of 10% or more between condyles is regarded as indicative of CH, and the affected condyles had a relative uptake of 55% or more. When the diagnosis of active CH is established, the treatment consists of removal of the growth center by a partial condylectomy. The authors present the case of a 46-year-old male patient with right active type II CH or hemimandibular hyperplasia who underwent a high condylectomy.

  18. Mandibular coronoid hyperplasia: a case report.

    PubMed

    Yura, Shinya; Ohga, Noritaka; Ooi, Kazuhiro; Izumiyama, Yuri

    2009-10-01

    A case of unilateral coronoid hyperplasia successfully treated by coronoidotomy with prolonged postoperative physiotherapy and reveal the postoperative radiographic changes between the sectioned part of the coronoid process and the mandibular ascending ramus is described. The patient was a 28-year-old man whose maximum mouth opening was 30 mm. A coronoidotomy of the left coronoid process was performed. Nine days after surgery, the patient started physiotherapy with a HU-OS(r) appliance. After coronoidotomy and physiotherapy, the maximum mouth opening had increased to 43 mm. Radiographic follow-up showed that the coronoid process apparently united with the mandibular ascending ramus, with moderate dislocation and inclination posteriorly. In the case presented, an intraoral coronoidotomy with postoperative physiotherapy for treatment of coronoid process hyperplasia allowed satisfactory and stable results in the correction of coronoid-malar interference.

  19. Focal epithelial hyperplasia in a Turkish family.

    PubMed

    Gökahmetoğlu, Selma; Ferahbaş, Ayten; Canöz, Özlem

    2014-12-01

    Focal epithelial hyperplasia (FEH) is a benign proliferative condition that is more frequently found in children of certain ethnic groups. Human papillomavirus (HPV) 13 and 32 genotypes has been consistently detected in these lesions. In this study a daughter, mother and father had FEH, and HPV 13 was shown by sequence analysis in the lesions of these patients. Cryotherapy was applied to the lesions and the lesions improved, but did not recover properly. In conclusion, HPV genotyping should be performed in FEH cases.

  20. Extensive focal epithelial hyperplasia: case report.

    PubMed

    Durso, Braz Campos; Pinto, José Marcelo Vargas; Jorge, Jacks; de Almeida, Oslei Paes

    2005-11-01

    Focal epithelial hyperplasia (FEH) is a rare benign lesion caused by human papillomavirus subtype 13 or 32. The condition occurs in numerous populations and ethnic groups. A higher incidence in close communities and among family members indicates infectious pathogenesis. A 21-year-old woman with FEH is described, in whom the lesions had persisted for 10 years. A literature review is also presented, with emphasis on manifestations in the oral mucosa and histopathological features.

  1. [Hepatocellular nodular hyperplasias, adenomas and carcinomas].

    PubMed

    Altmann, H W

    1995-01-01

    Nodular hyperplasias ("hyperplasiomas") are new formations whose development as a required and regulated response can be traced either to compensatory reactions to the loss of cells (regeneration in a narrow sense) and to decreased cellular performance, or to primary growth impulses. Included in this group are: the "macroregenerative nodules" after extensive cell losses; solitary nodules of uncertain etiology; and the minute foci of "micronodular transformation" whose origin can be traced to a particular disturbance of the hepatic blood supply. The so-called "adenomatous hyperplasias" of the cirrhotic liver that have a tendency towards carcinomatous change are not included in this group and are perhaps better considered as "hyperplasiogenic adenomas". The so-called "focal nodular hyperplasia" too, it must be stressed, should be separated from the simple hyperplasias, for it is more closely related to the adenomas, but represents a new formation of limited growth potential. Morphologically it is conspicuously subdivided by multiple connective tissue bands and scars, but it is above all characterized by metaplastically derived neoductuli, and hence it is appropriately designated as a "combined nodule". Among the true uninodular adenomas there are several variants differing in their morphology,--the so-called "atypical" or "intermediate" forms, that can give rise to carcinomas. The hepatocellular carcinoma, that may arise in a variety of ways, presents multiple cytological and histological variants, but only the so-called "fibrolamellar carcinoma" presents also a clinical peculiarity. "Hepatoblastomas" differ from the common hepatocellular carcinomas by their origin in early childhood from immature early precursor cells and, in the later phases of life, from redifferentiated cells that can even give rise to mesenchymal elements. There is no evidence of the existence of particular pluripotential stem cells.

  2. Hereditary Pituitary Hyperplasia with Infantile Gigantism

    PubMed Central

    Gläsker, Sven; Vortmeyer, Alexander O.; Lafferty, Antony R. A.; Hofman, Paul L.; Li, Jie; Weil, Robert J.; Zhuang, Zhengping

    2011-01-01

    Context: We report hereditary pituitary hyperplasia. Objective: The objective of the study was to describe the results of the clinical and laboratory analysis of this rare instance of hereditary pituitary hyperplasia. Design: The study is a retrospective analysis of three cases from one family. Setting: The study was conducted at the National Institutes of Health, a tertiary referral center. Patients: A mother and both her sons had very early-onset gigantism associated with high levels of serum GH and prolactin. Interventions: The condition was treated by total hypophysectomy. Main Outcome Measure(s): We performed clinical, pathological, and molecular evaluations, including evaluation basal and provocative endocrine testing, neuroradiological assessment, and assessment of the pituitary tissue by microscopic evaluation, immunohistochemistry, and electron microscopy. Results: All three family members had very early onset of gigantism associated with abnormally high serum levels of GH and prolactin. Serum GHRH levels were not elevated in either of the boys. The clinical, radiographic, surgical, and histological findings indicated mammosomatotroph hyperplasia. The pituitary gland of both boys revealed diffuse mammosomatotroph hyperplasia of the entire pituitary gland without evidence of adenoma. Prolactin and GH were secreted by the same cells within the same secretory granules. Western blot and immunohistochemistry demonstrated expression of GHRH in clusters of cells distributed throughout the hyperplastic pituitary of both boys. Conclusions: This hereditary condition seems to be a result of embryonic pituitary maldevelopment with retention and expansion of the mammosomatotrophs. The findings suggest that it is caused by paracrine or autocrine pituitary GHRH secretion during pituitary development. PMID:21976722

  3. Metformin for endometrial hyperplasia: a Cochrane protocol

    PubMed Central

    Clement, Naomi S; Oliver, Thomas R W; Shiwani, Hunain; Saner, Juliane R F; Mulvaney, Caroline A; Atiomo, William

    2016-01-01

    Introduction Endometrial hyperplasia is a precancerous lesion of the endometrium, commonly presenting with uterine bleeding. If managed expectantly, it frequently progresses to endometrial carcinoma, rates of which are increasing dramatically worldwide. However, the established treatment for endometrial hyperplasia (progestogens) involves multiple side effects and leaves the risk of recurrence. Metformin is the most commonly used oral hypoglycaemic agent in type 2 diabetes mellitus. It has also been linked to the reversal of endometrial hyperplasia and may therefore contribute to decreasing the prevalence of endometrial carcinoma without the fertility and side effect consequences of current therapies. However, the efficacy and safety of metformin being used for this therapeutic target is unclear and, therefore, this systematic review will aim to determine this. Methods and analysis We will search the following trials and databases with no language restrictions: Cochrane Gynaecology and Fertility Specialised Register; Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; EMBASE; EBSCO Cumulative Index to Nursing and Allied Health Literature; PubMed; Google Scholar; ClinicalTrials.gov; the WHO International Trials Registry Platform portal; OpenGrey and the Latin American and Caribbean Health Sciences Literature (LILACS). We will include randomised controlled trials (RCTs) of use of metformin compared with a placebo or no treatment, conventional medical treatment (eg, progestogens) or any other active intervention. Two review authors will independently assess the trial eligibility, risk of bias and extract appropriate data points. Trial authors will be contacted for additional data. The primary review outcome is the regression of endometrial hyperplasia histology towards normal histology. Secondary outcomes include hysterectomy rate; abnormal uterine bleeding; quality of life scores and adverse reactions to treatments. Ethics and dissemination

  4. [Primary hyperaldosteronism due to unilateral adrenal hyperplasia with surgical resolution].

    PubMed

    Rubio-Puchol, O; Garzón-Pastor, S; Salom-Vendrell, C; Hernández-Mijares, A

    Unilateral adrenal hyperplasia is a rare cause of primary hyperaldosteronism (around a 3%) that has surgical treatment. A case of a patient with hypertension resistant to conventional therapy in treatment with 7 drugs who presented with primary hyperaldosteronism due to unilateral adrenal hyperplasia is presented. A left adrenalectomy was performed, and the patient had a good clinical response, with no need of any drug after 2 years of surgery. Unilateral adrenal hyperplasia is a different entity and it is not an asymmetric variant of the bilateral adrenal hyperplasia. In the study of patients with primary hyperaldosteronism and imaging tests with absence of adenoma is a diagnosis that must be considered before cataloguing patients with bilateral adrenal hyperplasia and start a medical treatment, because unilateral adrenal hyperplasia would have a surgical resolution.

  5. Regenerative Endodontics: A Road Less Travelled

    PubMed Central

    Bansal, Ramta; Mittal, Sunandan; Kumar, Tarun; Kaur, Dilpreet

    2014-01-01

    Although traditional approaches like root canal therapy and apexification procedures have been successful in treating diseased or infected root canals, but these modalities fail to re-establish healthy pulp tissue in treated teeth. Regeneration-based approaches aims to offer high levels of success by replacing diseased or necrotic pulp tissues with healthy pulp tissue to revitalize teeth. The applications of regenerative approaches in dental clinics have potential to dramatically improve patients’ quality of life. This review article offers a detailed overview of present regenerative endodontic approaches aiming to revitalize teeth and also outlines the problems to be dealt before this emerging field contributes to clinical treatment protocols. It conjointly covers the basic trilogy elements of tissue engineering. PMID:25478476

  6. Regenerative endodontics: a road less travelled.

    PubMed

    Bansal, Ramta; Jain, Aditya; Mittal, Sunandan; Kumar, Tarun; Kaur, Dilpreet

    2014-10-01

    Although traditional approaches like root canal therapy and apexification procedures have been successful in treating diseased or infected root canals, but these modalities fail to re-establish healthy pulp tissue in treated teeth. Regeneration-based approaches aims to offer high levels of success by replacing diseased or necrotic pulp tissues with healthy pulp tissue to revitalize teeth. The applications of regenerative approaches in dental clinics have potential to dramatically improve patients' quality of life. This review article offers a detailed overview of present regenerative endodontic approaches aiming to revitalize teeth and also outlines the problems to be dealt before this emerging field contributes to clinical treatment protocols. It conjointly covers the basic trilogy elements of tissue engineering.

  7. Micro-Scale Regenerative Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Moran, Matthew E.; Stelter, Stephan; Stelter, Manfred

    2004-01-01

    A micro-scale regenerative heat exchanger has been designed, optimized and fabricated for use in a micro-Stirling device. Novel design and fabrication techniques enabled the minimization of axial heat conduction losses and pressure drop, while maximizing thermal regenerative performance. The fabricated prototype is comprised of ten separate assembled layers of alternating metal-dielectric composite. Each layer is offset to minimize conduction losses and maximize heat transfer by boundary layer disruption. A grating pattern of 100 micron square non-contiguous flow passages were formed with a nominal 20 micron wall thickness, and an overall assembled ten-layer thickness of 900 microns. Application of the micro heat exchanger is envisioned in the areas of micro-refrigerators/coolers, micropower devices, and micro-fluidic devices.

  8. Chemical transdifferentiation: closer to regenerative medicine.

    PubMed

    Xu, Aining; Cheng, Lin

    2016-06-01

    Cell transdifferentiation, which directly switches one type of differentiated cells into another cell type, is more advantageous than cell reprogramming to generate pluripotent cells and differentiate them into functional cells. This process is crucial in regenerative medicine. However, the cell-converting strategies, which mainly depend on the virus-mediated expression of exogenous genes, have clinical safety concerns. Small molecules with compelling advantages are a potential alternative in manipulating cell fate conversion. In this review, we briefly retrospect the nature of cell transdifferentiation and summarize the current developments in the research of small molecules in promoting cell conversion. Particularly, we focus on the complete chemical compound-induced cell transdifferentiation, which is closer to the clinical translation in cell therapy. Despite these achievements, the mechanisms underpinning chemical transdifferentiation remain largely unknown. More importantly, identifying drugs that induce resident cell conversion in vivo to repair damaged tissue remains to be the end-goal in current regenerative medicine.

  9. Unitized Regenerative Fuel Cell System Model Development

    NASA Technical Reports Server (NTRS)

    Burke, Kenneth A.; Jakupca, Ian

    2003-01-01

    A Unitized Regenerative Fuel Cell (URFC) Energy Storage System is being developed at the NASA Glenn Research Center. This URFC system is unique in that it uses the surface area of the hydrogen and oxygen storage tanks as radiating heat surfaces for overall thermal control of the system. The tank surfaces also play an important role in the temperature control of regenerative gas dryers/humidifiers used to dry the hydrogen and oxygen gases produced by electrolysis during the charging and also used to humidify the hydrogen and oxygen gases used by fuel cell during the discharging of the URFCS. A bi- directional pressure controller is used to control the pressure of the oxygen and hydrogen gas inside the URFC stack during both charging and discharging of the URFC system. A water storage accumulator is used to store water reactant and control water pressure inside the URFC stack.

  10. Electrospun Silk Biomaterial Scaffolds for Regenerative Medicine

    PubMed Central

    Zhang, Xiaohui; Reagan, Michaela R; Kaplan, David L.

    2009-01-01

    Electrospinning is a versatile technique that enables the development of nanofiber-based biomaterial scaffolds. Scaffolds can be generated that are useful for tissue engineering and regenerative medicine since they mimic the nanoscale properties of certain fibrous components of the native extracellular matrix in tissues. Silk is a natural protein with excellent biocompatibility, remarkable mechanical properties as well as tailorable degradability. Integrating these protein polymer advantages with electrospinning results in scaffolds with combined biochemical, topographical and mechanical cues with versatility for a range of biomaterial, cell and tissue studies and applications. This review covers research related to electrospinning of silk, including process parameters, post treatment of the spun fibers, functionalization of nanofibers, and the potential applications for these material systems in regenerative medicine. Research challenges and future trends are also discussed. PMID:19643154

  11. Fluorescent Cell Imaging in Regenerative Medicine

    PubMed Central

    Sapoznik, Etai; Niu, Guoguang; Zhou, Yu; Murphy, Sean V.; Soker, Shay

    2016-01-01

    Fluorescent protein imaging, a promising tool in biological research, incorporates numerous applications that can be of specific use in the field of regenerative medicine. To enhance tissue regeneration efforts, scientists have been developing new ways to monitor tissue development and maturation in vitro and in vivo. To that end, new imaging tools and novel fluorescent proteins have been developed for the purpose of performing deep-tissue high-resolution imaging. These new methods, such as intra-vital microscopy and Förster resonance energy transfer, are providing new insights into cellular behavior, including cell migration, morphology, and phenotypic changes in a dynamic environment. Such applications, combined with multimodal imaging, significantly expand the utility of fluorescent protein imaging in research and clinical applications of regenerative medicine. PMID:27158228

  12. Regenerative endodontics: a state of the art.

    PubMed

    Bansal, Rashmi; Bansal, Rajesh

    2011-01-01

    Scientific advances in the creation of restorative biomaterials, in vitro cell culture technology, tissue grafting, tissue engineering, molecular biology and the human genome project provide the basis for the introduction of new technologies into dentistry. Non-vital infected teeth have long been treated with root canal therapy (for mature root apex) and apexification (for immature root apex), or doomed to extraction. Although successful, current treatments fail to re-establish healthy pulp tissue in these teeth. But, what if the non-vital tooth could be made vital once again? That is the hope offered by regenerative endodontics, an emerging field focused on replacing traumatized and diseased pulp with functional pulp tissue. Restoration of vitality of non-vital tooth is based on tissue engineering and revascularization procedures. The purpose of this article is to review these biological procedures and the hurdles that must be overcome to develop regenerative endodontic procedures.

  13. [Progress in stem cells and regenerative medicine].

    PubMed

    Wang, Libin; Zhu, He; Hao, Jie; Zhou, Qi

    2015-06-01

    Stem cells have the ability to differentiate into all types of cells in the body and therefore have great application potential in regenerative medicine, in vitro disease modelling and drug screening. In recent years, stem cell technology has made great progress, and induced pluripotent stem cell technology revolutionizes the whole stem cell field. At the same time, stem cell research in our country has also achieved great progress and becomes an indispensable power in the worldwide stem cell research field. This review mainly focuses on the research progress in stem cells and regenerative medicine in our country since the advent of induced pluripotent stem cell technology, including induced pluripotent stem cells, transdifferentiation, haploid stem cells, and new gene editing tools.

  14. Induced pluripotent stem cells for regenerative medicine.

    PubMed

    Hirschi, Karen K; Li, Song; Roy, Krishnendu

    2014-07-11

    With the discovery of induced pluripotent stem (iPS) cells, it is now possible to convert differentiated somatic cells into multipotent stem cells that have the capacity to generate all cell types of adult tissues. Thus, there is a wide variety of applications for this technology, including regenerative medicine, in vitro disease modeling, and drug screening/discovery. Although biological and biochemical techniques have been well established for cell reprogramming, bioengineering technologies offer novel tools for the reprogramming, expansion, isolation, and differentiation of iPS cells. In this article, we review these bioengineering approaches for the derivation and manipulation of iPS cells and focus on their relevance to regenerative medicine.

  15. Endometrial stem cells in regenerative medicine.

    PubMed

    Verdi, Javad; Tan, Aaron; Shoae-Hassani, Alireza; Seifalian, Alexander M

    2014-01-01

    First described in 2004, endometrial stem cells (EnSCs) are adult stem cells isolated from the endometrial tissue. EnSCs comprise of a population of epithelial stem cells, mesenchymal stem cells, and side population stem cells. When secreted in the menstrual blood, they are termed menstrual stem cells or endometrial regenerative cells. Mounting evidence suggests that EnSCs can be utilized in regenerative medicine. EnSCs can be used as immuno-modulatory agents to attenuate inflammation, are implicated in angiogenesis and vascularization during tissue regeneration, and can also be reprogrammed into induced pluripotent stem cells. Furthermore, EnSCs can be used in tissue engineering applications and there are several clinical trials currently in place to ascertain the therapeutic potential of EnSCs. This review highlights the progress made in EnSC research, describing their mesodermal, ectodermal, and endodermal potentials both in vitro and in vivo.

  16. Denture hyperplasia with areas simulating oral inverted ductal papilloma.

    PubMed

    Vargas, Pablo Agustin; Perez, Danyel Elias da Cruz; Jorge, Jacks; Rangel, Ana Lúcia Carrinho Ayrosa; León, Jorge Esquiche; Almeida, Oslei Paes de

    2005-07-01

    Denture hyperplasia is a reactive lesion of the oral mucosa, usually associated to an ill-fitting denture. This lesion is easily diagnosed and in some cases distinct microscopic variations such as osseous, oncocytic and squamous metaplasia may be found. These metaplastic alterations probably are associated with the lymphocytic infiltrate usually present in denture hyperplasia. We present a case of denture hyperplasia containing salivary gland tissue with ductal alterations mimicking an oral inverted ductal papilloma.

  17. 18F-FDG-avid brunner gland hyperplasia.

    PubMed

    Park, Seol Hoon; Park, Kwang-Min; Kim, Jae Seung

    2014-08-01

    Brunner gland hyperplasia, a rare duodenal tumor, usually presents with benign features. A 68-year-old man with a history of anemia presented with a polypoid duodenal mass that was detected by CT and esophagogastroduodenoscopy. This mass showed high F-FDG avidity on PET/CT and was histopathologically confirmed as Brunner gland hyperplasia. We suggest that Brunner gland hyperplasia should be considered in the differential diagnosis of F-FDG-avid duodenal tumors.

  18. Unilateral condylar hyperplasia: A case report and review of literature.

    PubMed

    Bharathi, Saravana C; Senthilnathan, S; Kumar, Lokesh D; Mohan, Anand C S; Taranath, M

    2014-01-01

    Condylar hyperplasia is (CH) an uncommon malformation of the mandible involving change in size and morphology of the condylar neck and head. CH is an anomaly that usually occurs unilaterally and equally affects in both men and women. Hyperplasia of the condyle 'differentiated into hemimandibular hyperplasia, hemimandibular elongation and CH. Here, we are presenting a case of 17-year-old male patient with unilateral CH and its review of the literature.

  19. A solar regenerative thermoelectrochemical converter (RTEC)

    SciTech Connect

    Townsend, C.W.; McHardy, J. )

    1992-02-01

    This is an executive summary of a final subcontract report that describes the successful completion of a closed-loop demonstration of a regenerative thermoelectromechanical device using solar heat input for the production of electricity. The full report, which contains a detailed description of the two-year effort, is currently subject to a government secrecy order which precludes public release of the information. Copies of the full report will be made available for general release whenever the secrecy order is lifted.

  20. Regenerative medicine. The industry comes of age.

    PubMed

    Mason, C

    2007-01-01

    The regenerative medicine industry has moved into a new era in which commercialisation and not research is the number one priority. To achieve its new goal, much has had to change, including the introduction of expert business management, simpler but superior products and scalability of manufacture. Mass public and political support is supplying both long-term resources and the market demand to finally create a sustainable new health-care sector.

  1. Nanostructured polymeric scaffolds for orthopaedic regenerative engineering.

    PubMed

    Deng, Meng; James, Roshan; Laurencin, Cato T; Kumbar, Sangamesh G

    2012-03-01

    Successful regeneration necessitates the development of three-dimensional (3-D) tissue-inducing scaffolds that mimic the hierarchical architecture of native tissue extracellular matrix (ECM). Cells in nature recognize and interact with the surface topography they are exposed to via ECM proteins. The interaction of cells with nanotopographical features such as pores, ridges, groves, fibers, nodes, and their combinations has proven to be an important signaling modality in controlling cellular processes. Integrating nanotopographical cues is especially important in engineering complex tissues that have multiple cell types and require precisely defined cell-cell and cell-matrix interactions on the nanoscale. Thus, in a regenerative engineering approach, nanoscale materials/scaffolds play a paramount role in controlling cell fate and the consequent regenerative capacity. Advances in nanotechnology have generated a new toolbox for the fabrication of tissue-specific nanostructured scaffolds. For example, biodegradable polymers such as polyesters, polyphosphazenes, polymer blends and composites can be electrospun into ECM-mimicking matrices composed of nanofibers, which provide high surface area for cell attachment, growth, and differentiation. This review provides the fundamental guidelines for the design and development of nanostructured scaffolds for the regeneration of various tissue types in human upper and lower extremities such as skin, ligament, tendon, and bone. Examples focusing on the collective work of our laboratory in those areas are discussed to demonstrate the regenerative efficacy of this approach. Furthermore, preliminary strategies and significant challenges to integrate these individual tissues into one complex organ through regenerative engineering-based integrated graft systems are also discussed.

  2. Low temperature thermally regenerative electrochemical system

    DOEpatents

    Loutfy, Raouf O.; Brown, Alan P.; Yao, Neng-Ping

    1983-01-01

    A thermally regenerative electrochemical system including an electrochemical cell with two water-based electrolytes separated by an ion exchange membrane, at least one of the electrolytes containing a complexing agent and a salt of a multivalent metal whose respective order of potentials for a pair of its redox couples is reversible by a change in the amount of the complexing agent in the electrolyte, the complexing agent being removable by distillation to cause the reversal.

  3. Low-temperature thermally regenerative electrochemical system

    DOEpatents

    Loutfy, R.O.; Brown, A.P.; Yao, N.P.

    1982-04-21

    A thermally regenerative electrochemical system is described including an electrochemical cell with two water-based electrolytes separated by an ion exchange membrane, at least one of the electrolytes containing a complexing agent and a salt of a multivalent metal whose respective order of potentials for a pair of its redox couples is reversible by a change in the amount of the ocmplexing agent in the electrolyte, the complexing agent being removable by distillation to cause the reversal.

  4. Mesenchymal stem cells in regenerative rehabilitation

    PubMed Central

    Nurkovic, Jasmin; Dolicanin, Zana; Mustafic, Fahrudin; Mujanovic, Rifat; Memic, Mensur; Grbovic, Vesna; Skevin, Aleksandra Jurisic; Nurkovic, Selmina

    2016-01-01

    [Purpose] Regenerative medicine and rehabilitation contribute in many ways to a specific plan of care based on a patient’s medical status. The intrinsic self-renewing, multipotent, regenerative, and immunosuppressive properties of mesenchymal stem cells offer great promise in the treatment of numerous autoimmune, degenerative, and graft-versus-host diseases, as well as tissue injuries. As such, mesenchymal stem cells represent a therapeutic fortune in regenerative medicine. The aim of this review is to discuss possibilities, limitations, and future clinical applications of mesenchymal stem cells. [Subjects and Methods] The authors have identified and discussed clinically and scientifically relevant articles from PubMed that have met the inclusion criteria. [Results] Direct treatment of muscle injuries, stroke, damaged peripheral nerves, and cartilage with mesenchymal stem cells has been demonstrated to be effective, with synergies seen between cellular and physical therapies. Over the past few years, several researchers, including us, have shown that there are certain limitations in the use of mesenchymal stem cells. Aging and spontaneous malignant transformation of mesenchymal stem cells significantly affect the functionality of these cells. [Conclusion] Definitive conclusions cannot be made by these studies because limited numbers of patients were included. Studies clarifying these results are expected in the near future. PMID:27390452

  5. Common ethical issues in regenerative medicine.

    PubMed

    Awaya, Tsuyoshi

    2005-01-01

    One of the common ethical issues in regenerative medicine is progress in 'componentation' (= being treated as parts) of the human body, and the enhancement of the view of such "human body parts." 'Componentation' of the human body represents a preliminary step toward commodification of the human body. The process of commodification of the human body follows the steps of 'materialization' (= being treated as a material object) [first step] -- 'componentation' [second step] -- 'resourcialization' (= being treated as resources) [third step] -- commodification [fourth step]. Transplantation medicine and artificial organ developments have dramatically exposed the potential of organs and tissues as parts, and regenerative medicine has a role in advancing 'componentation' of the human body and further enhancing the view of human body parts. The 'componentation' of the human body, regardless of the degree of regenerative medicine's contribution to it, is considered as a challenge to the traditional view of human bodies and the abstract value of "Human Dignity" in the same way or alongside the 'resourcialization' and commodification. However, in the future, a new perspective of human bodies that means "a perspective whereby human bodies, organs, tissues, and even the bodies themselves are perceived as disposable tools like disposable cameras, syringes, or contact lens" and therefore a new ethical view, suitable for a new reality, may emerge.

  6. Upconversion Nanoparticles for Bioimaging and Regenerative Medicine

    PubMed Central

    González-Béjar, María; Francés-Soriano, Laura; Pérez-Prieto, Julia

    2016-01-01

    Nanomaterials are proving useful for regenerative medicine in combination with stem cell therapy. Nanoparticles (NPs) can be administrated and targeted to desired tissues or organs and subsequently be used in non-invasive real-time visualization and tracking of cells by means of different imaging techniques, can act as therapeutic agent nanocarriers, and can also serve as scaffolds to guide the growth of new tissue. NPs can be of different chemical nature, such as gold, iron oxide, cadmium selenide, and carbon, and have the potential to be used in regenerative medicine. However, there are still many issues to be solved, such as toxicity, stability, and resident time. Upconversion NPs have relevant properties such as (i) low toxicity, (ii) capability to absorb light in an optical region where absorption in tissues is minimal and penetration is optimal (note they can also be designed to emit in the near-infrared region), and (iii) they can be used in multiplexing and multimodal imaging. An overview on the potentiality of upconversion materials in regenerative medicine is given. PMID:27379231

  7. Regenerative endodontics--Creating new horizons.

    PubMed

    Dhillon, Harnoor; Kaushik, Mamta; Sharma, Roshni

    2016-05-01

    Trauma to the dental pulp, physical or microbiologic, can lead to inflammation of the pulp followed by necrosis. The current treatment modality for such cases is non-surgical root canal treatment. The damaged tissue is extirpated and the root canal system prepared. It is then obturated with an inert material such a gutta percha. In spite of advances in techniques and materials, 10%-15% of the cases may end in failure of treatment. Regenerative endodontics combines principles of endodontics, cell biology, and tissue engineering to provide an ideal treatment for inflamed and necrotic pulp. It utilizes mesenchymal stem cells, growth factors, and organ tissue culture to provide treatment. Potential treatment modalities include induction of blood clot for pulp revascularization, scaffold aided regeneration, and pulp implantation. Although in its infancy, successful treatment of damaged pulp tissue has been performed using principles of regenerative endodontics. This field is dynamic and exciting with the ability to shape the future of endodontics. This article highlights the fundamental concepts, protocol for treatment, and possible avenues for research in regenerative endodontics.

  8. Mesenchymal stem cells in regenerative rehabilitation.

    PubMed

    Nurkovic, Jasmin; Dolicanin, Zana; Mustafic, Fahrudin; Mujanovic, Rifat; Memic, Mensur; Grbovic, Vesna; Skevin, Aleksandra Jurisic; Nurkovic, Selmina

    2016-06-01

    [Purpose] Regenerative medicine and rehabilitation contribute in many ways to a specific plan of care based on a patient's medical status. The intrinsic self-renewing, multipotent, regenerative, and immunosuppressive properties of mesenchymal stem cells offer great promise in the treatment of numerous autoimmune, degenerative, and graft-versus-host diseases, as well as tissue injuries. As such, mesenchymal stem cells represent a therapeutic fortune in regenerative medicine. The aim of this review is to discuss possibilities, limitations, and future clinical applications of mesenchymal stem cells. [Subjects and Methods] The authors have identified and discussed clinically and scientifically relevant articles from PubMed that have met the inclusion criteria. [Results] Direct treatment of muscle injuries, stroke, damaged peripheral nerves, and cartilage with mesenchymal stem cells has been demonstrated to be effective, with synergies seen between cellular and physical therapies. Over the past few years, several researchers, including us, have shown that there are certain limitations in the use of mesenchymal stem cells. Aging and spontaneous malignant transformation of mesenchymal stem cells significantly affect the functionality of these cells. [Conclusion] Definitive conclusions cannot be made by these studies because limited numbers of patients were included. Studies clarifying these results are expected in the near future.

  9. Genetic causation of neointimal hyperplasia in hemodialysis vascular access dysfunction.

    PubMed

    Lee, Timmy; Wadehra, Davinder

    2012-01-01

    The major cause of hemodialysis vascular access failure is venous stenosis resulting from neointimal hyperplasia. Genetic factors have been shown to be associated with cardiovascular disease and peripheral vascular disease (PVD) in the general population. Genetic factors may also play an important role in vascular access stenosis and development of neointimal hyperplasia by affecting pathways that lead to inflammation, endothelial function, oxidative stress, and vascular smooth muscle proliferation. This review will discuss the role of genetics in understanding neointimal hyperplasia development in hemodialysis vascular access dysfunction and other disease processes with similar neointimal hyperplasia development such as coronary artery disease and PVD.

  10. Genetic Causation of Neointimal Hyperplasia in Hemodialysis Vascular Access Dysfunction

    PubMed Central

    Lee, Timmy; Wadehra, Davinder

    2014-01-01

    The major cause of hemodialysis vascular access failure is venous stenosis resulting from neointimal hyperplasia. Genetic factors have been shown to be associated with cardiovascular disease (CVD) and peripheral vascular disease (PVD) in the general population. Genetic factors may also play an important role in vascular access stenosis and development of neointimal hyperplasia by affecting pathways that lead to inflammation, endothelial function, oxidative stress, and vascular smooth muscle proliferation. This review will discuss the role of genetics in understanding neointimal hyperplasia development in hemodialysis vascular access dysfunction and other disease processes with similar neointimal hyperplasia development such coronary artery disease and peripheral vascular disease. PMID:21917012

  11. Inflammatory papillary hyperplasia: A systematic review

    PubMed Central

    Gual-Vaqués, Patricia; Jané-Salas, Enric; Egido-Moreno, Sonia; Ayuso-Montero, Raúl; Marí-Roig, Antoni

    2017-01-01

    Introduction Inflammatory papillary hyperplasia (IPH) is a benign lesion of the palatal mucosa. It is usually found in denture-wearers but also has been reported in patients without a history of use of a maxillary prosthesis use. Objetives The aim of this study is to review the literature to assess the prevalence of denture stomatitis and inflammatory papillary hyperplasia and the etiological factors associated. Material and Methods A search was carried out in PubMed (January 2005 to October 2015) with the key words “inflammatory papillary hyperplasia”, “denture stomatitis”, “granular stomatitis” and “Newton’s type III” The inclusion criteria were studies including at least a sample of 50 apparently healthy patients, articles published from 2005 to 2015 written in English. The exclusion criteria were reviews and non-human studies. Results Out of the 190 studies obtained initially from the search 16 articles were selected to be included in our systematic review. The prevalence of denture stomatitis was 29.56% and 4.44% for IPH. We found 5 cases of denture stomatitis among non-denture-wearer individuals. All IPH cases were associated with the use of prosthesis. Smoking and continued use of ill-fitting dentures turned out to be the most frequent risk factors for developing IPH. Conclusions IPH is a rare oral lesion and its pathogenesis still remains unclear. Its presentation among non-denture-wearers is extremely unusual. Key words:Inflammatory papillary hyperplasia, denture stomatitis, prevalence, granular stomatitis, Newton’s type III stomatitis. PMID:27918740

  12. Steroid 21 hydroxylase deficiency congenital adrenal hyperplasia.

    PubMed

    Nimkarn, Saroj; Lin-Su, Karen; New, Maria I

    2011-10-01

    Steroid 21 hydroxylase deficiency is the most common form of congenital adrenal hyperplasia (CAH). The severity of this disorder depends on the extent of impaired enzymatic activity, which is caused by various mutations of the 21 hydroxylase gene. This article reviews adrenal steroidogenesis and the pathophysiology of 21 hydroxylase deficiency. The three forms of CAH are then discussed in terms of clinical presentation, diagnosis and treatment, and genetic basis. Prenatal diagnosis and treatment are also reviewed. The goal of therapy is to correct the deficiency in cortisol secretion and suppress androgen overproduction. Glucocorticoid replacement has been the mainstay of treatment for CAH, but new treatment strategies continue to be developed and studied.

  13. Adrenal Steroidogenesis and Congenital Adrenal Hyperplasia

    PubMed Central

    Turcu, Adina F.; Auchus, Richard J.

    2015-01-01

    Synopsis Adrenal steroidogenesis is a dynamic process, reliant on de novo synthesis from cholesterol, under the stimulation of ACTH and other regulators. The syntheses of mineralocorticoids, glucocorticoids and adrenal androgens occur in separate adrenal cortical zones, each expressing specific enzymes. Congenital adrenal hyperplasia (CAH) encompasses a group of autosomal recessive enzymatic defects in cortisol biosynthesis. 21-hydroxylase (21OHD) deficiency accounts for over 90% of CAH cases and when milder or nonclassic forms are included, 21OHD is one of the most common genetic diseases. This review discusses in detail the epidemiology, genetics, diagnostic, clinical aspects and management of 21OHD. PMID:26038201

  14. Multifocal epithelial hyperplasia: report of 3 cases.

    PubMed

    Tehranchinia, Zohreh; Mozafari, Nikoo; Barikbin, Behrooz; Nadji, Seyed Alireza

    2014-08-17

    Multifocal epithelial hyperplasia (MEH) is a rare disorder characterized by multiple painless discrete and soft flattened papules on the oral mucosa. It is caused by human papilloma virus 13 and 32. The frequency of this disease varies widely from one geographic region to another. Generally it is very rare in Asia. Herein we report 3 Iranian cases with oral lesions, which showed clinical and histopathological characteristics of MEH disease. Two of them were siblings and HPV13 was detected in one of the patients.

  15. Diode-pumped regenerative Yb:SrF2 amplifier

    NASA Astrophysics Data System (ADS)

    Ricaud, S.; Georges, P.; Camy, P.; Doualan, J.-L.; Moncorgé, R.; Courjaud, A.; Mottay, E.; Druon, F.

    2012-03-01

    We report what we believe to be the first Yb:SrF2 regenerative femtosecond amplifier. The regenerative amplifier produces 325-fs pulses at 100-Hz repetition rate with an energy before compression of 1.4 mJ. The interest of Yb:SrF2 in such regenerative amplifiers and its complementarity to its well-known isotype Yb:CaF2 is also discussed.

  16. Focal epithelial hyperplasia caused by human papillomavirus 13.

    PubMed

    Saunders, Natasha R; Scolnik, Dennis; Rebbapragada, Anuradha; Koelink, Eric; Craw, Lindsey; Roth, Sherryn; Aronson, Leya; Perusini, Stephen; Silverman, Michael S

    2010-06-01

    Focal epithelial hyperplasia is a benign, papulo-nodular disease of the oral cavity. It is rare, affecting primarily Native American populations during childhood. It is closely associated with human papillomavirus 13 and 32. This report describes the diagnosis of 2 cases of focal epithelial hyperplasia in children from southern Guyana. The diagnosis was made using clinical criteria, polymerase chain reaction, and DNA sequencing.

  17. Pseudocarcinomatous hyperplasia involving the ear from gout: a diagnostic pitfall.

    PubMed

    Morrissey, Kelly A; Garcia-Albea, Victoria; Goldberg, Lynne J

    2014-01-01

    The ear is a characteristic location for deposition of uric acid in patients with gout. Pseudocarcinomatous hyperplasia has not been described in this location. We report three patients with tophaceous gout on the ear whose biopsies exhibited epidermal hyperplasia mimicking squamous cell carcinoma, in order to call attention to this potential diagnostic pitfall.

  18. Could we also be regenerative superheroes, like salamanders?

    PubMed

    Dall'Agnese, Alessandra; Puri, Pier Lorenzo

    2016-09-01

    Development of methods to reawaken the semi-dormant regenerative potential that lies within adult human tissues would hold promise for the restoration of diseased or damaged organs and tissues. While most of the regeneration potential is suppressed in many vertebrates, including humans, during adult life, urodele amphibians (salamanders) retain their regenerative ability throughout adulthood. Studies in newts and axolotls, two salamander models, have provided significant knowledge about adult limb regeneration. In this review, we present a comparative analysis of salamander and mammalian regeneration and discuss how evolutionarily altered properties of the regenerative environment can be exploited to restore full regenerative potential in the human body.

  19. Platelet rich fibrin - a novel acumen into regenerative endodontic therapy

    PubMed Central

    Sharma, Krishna

    2014-01-01

    Research into regenerative dentistry has added impetus onto the field of molecular biology. It can be documented as a prototype shift in the therapeutic armamentarium for dental disease. Regenerative endodontic procedures are widely being added to the current armamentarium of pulp therapy procedures. The regenerative potential of platelets has been deliberated. A new family of platelet concentrates called the platelet rich fibrin (PRF) has been recently used by several investigators and has shown application in diverse disciplines of dentistry. This paper is intended to add light on the various prospects of PRF and clinical insights to regenerative endodontic therapy. PMID:24516822

  20. A Regeneratively-Cooled Thrust Chamber for the Fastrac Engine

    NASA Technical Reports Server (NTRS)

    Brown, Kendall; Sparks, Dave; Woodcock, Gordon; Jim Turner (Technical Monitor)

    2000-01-01

    This document consists of presentation slides about the development of the regeneratively cooled thrust chamber for the Fastrac engine. The Fastrac engine was originally developed to demonstrate low cost design and fabrication methods. It was intended to be used in an expendable booster. The regen thrust chamber enables a more cost efficient test program. Using the low cost design and fabrication methodology designed for the 12K regeneratively cooled chamber, the contractor designed, developed and fabricated a regeneratively cooled thrust chamber for the Fastrac engine.

  1. Clinical concepts for regenerative therapy in furcations.

    PubMed

    Sanz, Mariano; Jepsen, Karin; Eickholz, Peter; Jepsen, Søren

    2015-06-01

    Furcation involvements present one of the greatest challenges in periodontal therapy because furcation-involved molar teeth respond less favorably to conventional periodontal therapy compared with noninvolved molar or nonmolar teeth. Various regenerative procedures have been proposed and applied with the aim of eliminating the furcation defect or reducing the furcation depth. An abundance of studies and several systematic reviews have established the effectiveness of membrane therapy (guided tissue regeneration) for buccal Class II furcation involvement of mandibular and maxillary molars compared with open flap surgery. Bone grafts/substitutes may enhance the results of guided tissue regeneration. However, complete furcation closure is not a predictable outcome. Limited data and no meta-analyses are available on the effects of enamel matrix proteins for furcation regeneration. Enamel matrix protein therapy has demonstrated clinical improvements in the treatment of buccal Class II furcation defects in mandibular molars; however, complete closure of the furcation lesion is achieved only in a minority of cases. Neither guided tissue regeneration nor enamel matrix protein therapy have demonstrated predictable results for approximal Class II and for Class III furcations. Promising preclinical data from furcation regeneration studies in experimental animals is available for growth factor- and differentiation factor-based technologies, but very limited data are available from human clinical studies. Although cell-based therapies have received considerable attention in regenerative medicine, their experimental evaluation in the treatment of periodontal furcation lesions is at a very early stage of development. In summary, the indications and the limitations for currently available treatment modalities for furcation defects are well established. New regenerative treatments are clearly needed to improve the predictability of a complete resolution of furcation defects.

  2. Regenerative Blower for EVA Suit Ventilation Fan

    NASA Technical Reports Server (NTRS)

    Izenson, Michael G.; Chen, Weibo; Paul, Heather L.

    2010-01-01

    Portable life support systems in future space suits will include a ventilation subsystem driven by a dedicated fan. This ventilation fan must meet challenging requirements for pressure rise, flow rate, efficiency, size, safety, and reliability. This paper describes research and development that showed the feasibility of a regenerative blower that is uniquely suited to meet these requirements. We proved feasibility through component tests, blower tests, and design analysis. Based on the requirements for the Constellation Space Suit Element (CSSE) Portable Life Support System (PLSS) ventilation fan, we designed the critical elements of the blower. We measured the effects of key design parameters on blower performance using separate effects tests, and used the results of these tests to design a regenerative blower that will meet the ventilation fan requirements. We assembled a proof-of-concept blower and measured its performance at sub-atmospheric pressures that simulate a PLSS ventilation loop environment. Head/flow performance and maximum efficiency point data were used to specify the design and operating conditions for the ventilation fan. We identified materials for the blower that will enhance safety for operation in a lunar environment, and produced a solid model that illustrates the final design. The proof-of-concept blower produced the flow rate and pressure rise needed for the CSSE ventilation subsystem while running at 5400 rpm, consuming only 9 W of electric power using a non-optimized, commercial motor and controller and inefficient bearings. Scaling the test results to a complete design shows that a lightweight, compact, reliable, and low power regenerative blower can meet the performance requirements for future space suit life support systems.

  3. Therapeutic options for management of endometrial hyperplasia.

    PubMed

    Chandra, Vishal; Kim, Jong Joo; Benbrook, Doris Mangiaracina; Dwivedi, Anila; Rai, Rajani

    2016-01-01

    Endometrial hyperplasia (EH) comprises a spectrum of changes in the endometrium ranging from a slightly disordered pattern that exaggerates the alterations seen in the late proliferative phase of the menstrual cycle to irregular, hyperchromatic lesions that are similar to endometrioid adenocarcinoma. Generally, EH is caused by continuous exposure of estrogen unopposed by progesterone, polycystic ovary syndrome, tamoxifen, or hormone replacement therapy. Since it can progress, or often occur coincidentally with endometrial carcinoma, EH is of clinical importance, and the reversion of hyperplasia to normal endometrium represents the key conservative treatment for prevention of the development of adenocarcinoma. Presently, cyclic progestin or hysterectomy constitutes the major treatment option for EH without or with atypia, respectively. However, clinical trials of hormonal therapies and definitive standard treatments remain to be established for the management of EH. Moreover, therapeutic options for EH patients who wish to preserve fertility are challenging and require nonsurgical management. Therefore, future studies should focus on evaluation of new treatment strategies and novel compounds that could simultaneously target pathways involved in the pathogenesis of estradiol-induced EH. Novel therapeutic agents precisely targeting the inhibition of estrogen receptor, growth factor receptors, and signal transduction pathways are likely to constitute an optimal approach for treatment of EH.

  4. Torus hyperplasia of the pyloric antrum.

    PubMed

    Kim, Chi-Hun; Han, Hye Seung; Lee, Sun-Young; Kim, Byung Kook; Sung, In-Kyung; Seong, Moo Kyung; Lee, Kyung Yung

    2010-01-01

    Primary or idiopathic hypertrophy of the pyloric muscle in adult, so called torus hyperplasia, is an infrequent but an established entity. It is caused by a circular muscle hypertrophy affecting the lesser curvature near the pylorus. Since most of the lesions are difficult to differentiate from tumor, distal gastrectomy is usually preformed to rule out most causes of pyloric lesions including neoplastic ones through a pathological study. A 56-yr-old man with a family history of gastric cancer presented with abdominal discomfort of 1 month duration. Upper gastrointestinal endoscopy showed a 1.0 cm sized irregular submucosal lesion proximal to the pylorus to the distal antrum on the lesser curvature. On colonoscopy examination, a 1.5 cm sized protruding mass was noticed on the appendiceal orifice. Gastrectomy and cecectomy were done, and histological section revealed marked hypertrophy of the distal circular pyloric musculature and an appendiceal mucocele. To the best of our knowledge, this is the first case of torus hyperplasia with appendiceal mucocele which is found incidentally.

  5. Leydig Cell Hyperplasia Revealed by Gynecomastia

    PubMed Central

    Tazi, Mohamed Fadl; Mellas, Soufiane; El Fassi, Mohamed Jamal; Farih, Moulay Hassan

    2008-01-01

    Leydig cell tumors are rare and represent 1% to 3% of all tumors of the testis. Leydig cell tumors affect males at any age, but there are 2 peak periods of incidence: between 5 and 10 years and between 25 and 35 years. Their main clinical presentation is a testicular mass associated with endocrinal manifestations that are variable according to age and appearance of the tumor. Our patient, a 17-year-old adolescent, presented with an isolated and painless hypertrophy of the right mammary gland. Clinical examination found gynecomastia and no testicular mass. Hormonal levels and tumor markers were normal. Testicular sonography showed an ovular and homogeneous right intratesticular mass 6 mm in diameter. We treated the patient with an inguinal right orchidectomy. The anatomopathological study found a nodule of Leydig cell hyperplasia. The patient recovered without recurrence at 8-month follow-up. The patient opted for mammoplasty 2 months after his orchidectomy rather than wait for the spontaneous gradual regression of his gynecomastia, which requires at least 1 year. Leydig cell hyperplasia manifests in the adult by signs of hypogonadism, most frequently gynecomastia. Although many teams prefer total orchidectomy because of the diagnostic difficulty associated with malignant forms, simple subcapsular orchidectomy should become the first-line treatment, provided it be subsequently followed by close surveillance, as it preserves maximum fertility, and these tumors usually resolve favorably. PMID:18660859

  6. Leydig cell hyperplasia revealed by gynecomastia.

    PubMed

    Tazi, Mohamed Fadl; Mellas, Soufiane; El Fassi, Mohamed Jamal; Farih, Moulay Hassan

    2008-01-01

    Leydig cell tumors are rare and represent 1% to 3% of all tumors of the testis. Leydig cell tumors affect males at any age, but there are 2 peak periods of incidence: between 5 and 10 years and between 25 and 35 years. Their main clinical presentation is a testicular mass associated with endocrinal manifestations that are variable according to age and appearance of the tumor. Our patient, a 17-year-old adolescent, presented with an isolated and painless hypertrophy of the right mammary gland. Clinical examination found gynecomastia and no testicular mass. Hormonal levels and tumor markers were normal. Testicular sonography showed an ovular and homogeneous right intratesticular mass 6 mm in diameter. We treated the patient with an inguinal right orchidectomy. The anatomopathological study found a nodule of Leydig cell hyperplasia. The patient recovered without recurrence at 8-month follow-up. The patient opted for mammoplasty 2 months after his orchidectomy rather than wait for the spontaneous gradual regression of his gynecomastia, which requires at least 1 year. Leydig cell hyperplasia manifests in the adult by signs of hypogonadism, most frequently gynecomastia. Although many teams prefer total orchidectomy because of the diagnostic difficulty associated with malignant forms, simple subcapsular orchidectomy should become the first-line treatment, provided it be subsequently followed by close surveillance, as it preserves maximum fertility, and these tumors usually resolve favorably.

  7. Therapeutic options for management of endometrial hyperplasia

    PubMed Central

    2016-01-01

    Endometrial hyperplasia (EH) comprises a spectrum of changes in the endometrium ranging from a slightly disordered pattern that exaggerates the alterations seen in the late proliferative phase of the menstrual cycle to irregular, hyperchromatic lesions that are similar to endometrioid adenocarcinoma. Generally, EH is caused by continuous exposure of estrogen unopposed by progesterone, polycystic ovary syndrome, tamoxifen, or hormone replacement therapy. Since it can progress, or often occur coincidentally with endometrial carcinoma, EH is of clinical importance, and the reversion of hyperplasia to normal endometrium represents the key conservative treatment for prevention of the development of adenocarcinoma. Presently, cyclic progestin or hysterectomy constitutes the major treatment option for EH without or with atypia, respectively. However, clinical trials of hormonal therapies and definitive standard treatments remain to be established for the management of EH. Moreover, therapeutic options for EH patients who wish to preserve fertility are challenging and require nonsurgical management. Therefore, future studies should focus on evaluation of new treatment strategies and novel compounds that could simultaneously target pathways involved in the pathogenesis of estradiol-induced EH. Novel therapeutic agents precisely targeting the inhibition of estrogen receptor, growth factor receptors, and signal transduction pathways are likely to constitute an optimal approach for treatment of EH. PMID:26463434

  8. Diagnosis and management of benign prostatic hyperplasia.

    PubMed

    Edwards, Jonathan L

    2008-05-15

    Benign prostatic hyperplasia is a common condition affecting older men. Typical presenting symptoms include urinary hesitancy, weak stream, nocturia, incontinence, and recurrent urinary tract infections. Acute urinary retention, which requires urgent bladder catheterization, is relatively uncommon. Irreversible renal damage is rare. The initial evaluation should assess the frequency and severity of symptoms and the impact of symptoms on the patient's quality of life. The American Urological Association Symptom Index is a validated instrument for the objective assessment of symptom severity. The initial evaluation should also include a digital rectal examination and urinalysis. Men with hematuria should be evaluated for bladder cancer. A palpable nodule or induration of the prostate requires referral for assessment to rule out prostate cancer. For men with mild symptoms, watchful waiting with annual reassessment is appropriate. Over the past decade, numerous medical and surgical interventions have been shown to be effective in relieving symptoms of benign prostatic hyperplasia. Alpha blockers improve symptoms relatively quickly. Although 5-alpha reductase inhibitors have a slower onset of action, they may decrease prostate size and alter the disease course. Limited evidence shows that the herbal agents saw palmetto extract, rye grass pollen extract, and pygeum relieve symptoms. Transurethral resection of the prostate often provides permanent relief. Newer laser-based surgical techniques have comparable effectiveness to transurethral resection up to two years after surgery with lower perioperative morbidity. Various outpatient surgical techniques are associated with reduced morbidity, but symptom relief may be less durable.

  9. Regulating the therapeutic translation of regenerative medicine.

    PubMed

    Cuchiara, Maude L; Olive, Jackie K; Matthews, Kirstin

    2015-01-01

    Regenerative medicine and stem cell research are exciting new fields. But as the fields progress toward clinical therapies, controversies emerge. Hype surrounding stem cell research has caused an increase in their use in interventions that are not clinically proven. Furthermore, the regulatory agencies have a lot of difficulty dealing with cell therapies, which are distinctly different from drugs and medical devices they more commonly approve. To move the field forward, advocates, regulators and scientists need to come together to find new options for stem cell research oversight that protects both the patients and the research field.

  10. Regenerative nanotechnology in oral and maxillofacial surgery.

    PubMed

    Shakib, Kaveh; Tan, Aaron; Soskic, Vukic; Seifalian, Alexander M

    2014-12-01

    Regenerative nanotechnology is at the forefront of medical research, and translational medicine is a challenge to both scientists and clinicians. Although there has been an exponential rise in the volume of research generated about it for both medical and surgical uses, key questions remain about its actual benefits. Nevertheless, some people think that therapeutics based on its principles may form the core of applied research for the future. Here we give an account of its current use in oral and maxillofacial surgery, and implications and challenges for the future.

  11. The essential materials paradigms for regenerative medicine

    NASA Astrophysics Data System (ADS)

    Williams, David

    2011-04-01

    Medical technology is changing rapidly. Several disease states can now be treated very effectively by implantable devices that restore mechanical and physical functionality, such as replacement of hip joints or restoration of heart rhythms by pacemakers. These techniques, however, are rather limited, and no biological functionality can be restored through the use of inert materials and devices. This paper explores the role of new types of biomaterials within the emerging area of regenerative medicine, where they are able to play a powerful role in persuading the human body to regenerate itself.

  12. Collagen: a network for regenerative medicine

    PubMed Central

    Pawelec, K. M.; Best, S. M.

    2016-01-01

    The basic building block of the extra-cellular matrix in native tissue is collagen. As a structural protein, collagen has an inherent biocompatibility making it an ideal material for regenerative medicine. Cellular response, mediated by integrins, is dictated by the structure and chemistry of the collagen fibers. Fiber formation, via fibrillogenesis, can be controlled in vitro by several factors: pH, ionic strength, and collagen structure. After formation, fibers are stabilized via cross-linking. The final bioactivity of collagen scaffolds is a result of both processes. By considering each step of fabrication, scaffolds can be tailored for the specific needs of each tissue, improving their therapeutic potential. PMID:27928505

  13. Transpiration And Regenerative Cooling Of Rocket Engine

    NASA Technical Reports Server (NTRS)

    Obrien, Charles J.

    1989-01-01

    Transpiration cooling extends limits of performance. Addition of transpiration cooling to regeneratively-cooled rocket-engine combustion chamber proposed. Modification improves performance of engine by allowing use of higher chamber pressure. Throat section of combustion-chamber wall cooled by transpiration, while chamber and nozzle sections cooled by fluid flowing in closed channels. Concept applicable to advanced, high-performance terrestrial engines or some kinds of industrial combustion chambers. With proper design, cooling scheme makes possible to achieve higher chamber pressure and higher overall performance in smaller engine.

  14. Regenerative fuel cell systems for space station

    NASA Technical Reports Server (NTRS)

    Hoberecht, M. A.; Sheibley, D. W.

    1985-01-01

    Regenerative fuel cell (RFC) systems are the leading energy storage candidates for Space Station. Key design features are the advanced state of technology readiness and high degree of system level design flexibility. Technology readiness was demonstrated through testing at the single cell, cell stack, mechanical ancillary component, subsystem, and breadboard levels. Design flexibility characteristics include independent sizing of power and energy storage portions of the system, integration of common reactants with other space station systems, and a wide range of various maintenance approaches. The design features led to selection of a RFC system as the sole electrochemical energy storage technology option for the space station advanced development program.

  15. The strong financial case for regenerative medicine and the regen industry.

    PubMed

    Mason, Chris; Dunnill, Peter

    2008-05-01

    Although the therapeutic promise of regenerative medicine is immensely exciting, the cost of product development, and particularly of clinical trials, for the more demanding applications will be high. For this reason it is vital for scientists and start-ups who wish to see their ideas implemented to be able to convince established major pharmaceutical or device companies with the necessary 'deep pockets' that the expenditure can yield an appropriate return. It also means that governments and health insurance companies must see a gain in funding regenerative medicine for patients. To address this issue the costs of five major medical conditions that could benefit from regenerative medicine have been defined for the USA as an illustration. This choice of country was made as potentially the largest initial market and one where the billing system for healthcare allows access to individual direct and some indirect costs. The data are complemented by a number of relevant examples of costs per quality-adjusted life year to indicate where current treatment methods are weak or strong. Finally, the relationship of the nascent regen* industry to the pharma and medical device sectors is summarized to assess the challenge of encouraging their involvement.

  16. Progestin Therapy of Complex Endometrial Hyperplasia With and Without Atypia

    PubMed Central

    Reed, SD; Voigt, LF; Newton, KM; Garcia, R; Allison, HK; Epplein, M; Jordan, D; Swisher, E; Weiss, NS

    2009-01-01

    Precis Complex hyperplasia regression is common with and without progestin therapy, and the likelihood of atypical hyperplasia regression is greater with progestin therapy than without. Objective To assess likelihood of histologic persistence/progression of complex hyperplasia and atypical hyperplasia among women treated with progestin compared to those not treated, with attention to type, dose and duration. Methods This was a cohort study of women at an integrated health plan, ages 18-85 years, with complex or atypical hyperplasia on independent pathology review with a second endometrial specimen in the 2-6 months following the index diagnosis. Progestin therapy between index diagnosis and follow-up biopsy was determined from the pharmacy database. Medical record abstraction was performed. Relative risks (RR), adjusted for age and body mass index, were calculated. Results Among 185 women, average age 55.9 years, follow-up 16.1 weeks, 115 women had complex and 70 had atypical hyperplasia. Among women with complex hyperplasia 28.4% of women treated with progestin and 30.0% of those not treated had persistence/progression (RR 1.20, 95% confidence interval (CI) 0.53-2.72). Among women with atypical hyperplasia, 26.9% of those treated with progestin and 66.7% of those not treated had persistence/progression (RR 0.39, 95% CI 0.21-0.70); there was a suggestion that use of at least a medium dose, or a duration of at least 3 months, was associated with a particularly low probability of persistence/progression. Conclusion While progestin treatment of women with atypical hyperplasia was associated with a substantial increase in the likelihood of regression of the lesion during the ensuing 2-6 months, persistence/progression was nonetheless present in more than one-quarter of treated women. Regression of complex hyperplasia without atypia was common whether progestin had or had not been used. PMID:19300331

  17. Scaffolds in regenerative endodontics: A review

    PubMed Central

    Gathani, Kinjal M.; Raghavendra, Srinidhi Surya

    2016-01-01

    Root canal therapy has enabled us to save numerous teeth over the years. The most desired outcome of endodontic treatment would be when diseased or nonvital pulp is replaced with healthy pulp tissue that would revitalize the teeth through regenerative endodontics. ‘A search was conducted using the Pubmed and MEDLINE databases for articles with the criteria ‘Platelet rich plasma’, ‘Platelet rich fibrin’, ‘Stem cells’, ‘Natural and artificial scaffolds’ from 1982–2015’. Tissues are organized as three-dimensional structures, and appropriate scaffolding is necessary to provide a spatially correct position of cell location and regulate differentiation, proliferation, or metabolism of the stem cells. Extracellular matrix molecules control the differentiation of stem cells, and an appropriate scaffold might selectively bind and localize cells, contain growth factors, and undergo biodegradation over time. Different scaffolds facilitate the regeneration of different tissues. To ensure a successful regenerative procedure, it is essential to have a thorough and precise knowledge about the suitable scaffold for the required tissue. This article gives a review on the different scaffolds providing an insight into the new developmental approaches on the horizon. PMID:27857762

  18. Translational science in disinfection for regenerative endodontics.

    PubMed

    Diogenes, Anibal R; Ruparel, Nikita B; Teixeira, Fabricio B; Hargreaves, Kenneth M

    2014-04-01

    The endodontic management of permanent immature teeth is fraught with challenges. Although treatment modalities for vital pulp therapy in these teeth provide long-term favorable outcome, the outcomes from the treatment of pulp necrosis and apical periodontitis are significantly less predictable. Immature teeth diagnosed with pulp necrosis have been traditionally treated with apexification or apexogenesis approaches. Unfortunately, these treatments provide little to no benefit in promoting continued root development. Regenerative endodontic procedures have emerged as an important alternative in treating teeth with otherwise questionable long-term prognosis because of thin, fragile dentinal walls and a lack of immunocompetency. These procedures rely heavily on root canal chemical disinfection of the root canal system. Traditionally, irrigants and medicaments have been chosen for their maximum antimicrobial effect without consideration for their effects on stem cells and the dentinal microenvironment. Translational research has been crucial to provide evidence for treatment modifications that aim to increase favorable outcome while steering away from common pitfalls in the currently used protocols. In this review, recent advances learned from translational research related to disinfection in regenerative endodontics are presented and discussed.

  19. Regenerative fuel cell systems R and D

    SciTech Connect

    Mitlitsky, F.; Myers, B.; Weisberg, A.H.

    1998-08-01

    Regenerative fuel cell (RFC) systems produce power and electrolytically regenerate their reactants using stacks of electrochemical cells. Energy storage systems with extremely high specific energy (> 400 Wh/kg) have been designed that use lightweight pressure vessels to contain the gases generated by reversible (unitized) regenerative fuel cells (URFCs). Progress is reported on the development, integration, and operation of rechargeable energy storage systems with such high specific energy. Lightweight pressure vessels that enable high specific energies have been designed with performance factors (burst pressure/internal volume/tank weight) > 50 km (2.0 million inches), and a vessel with performance factor of 40 km (1.6 million inches) was fabricated. New generations of both advanced and industry-supplied hydrogen tankage are under development. A primary fuel cell test rig with a single cell (46 cm{sup 2} active area) has been modified and operated reversibly as a URFC (for up to 2010 cycles on a single cell). This URFC uses bifunctional electrodes (oxidation and reduction electrodes reverse roles when switching from charge to discharge, as with a rechargeable battery) and cathode feed electrolysis (water is fed from the hydrogen side of the cell). Recent modifications also enable anode feed electrolysis (water is fed from the oxygen side of the cell). Hydrogen/halogen URFCs, capable of higher round-trip efficiency than hydrogen/oxygen URFCs, have been considered, and will be significantly heavier. Progress is reported on higher performance hydrogen/oxygen URFC operation with reduced catalyst loading.

  20. Multiple excitation regenerative amplifier inertial confinement system

    DOEpatents

    George, Victor E. [Livermore, CA; Haas, Roger A. [Pleasanton, CA; Krupke, William F. [Pleasanton, CA; Schlitt, Leland G. [Livermore, CA

    1980-05-27

    The invention relates to apparatus and methods for producing high intensity laser radiation generation which is achieved through an optical amplifier-storage ring design. One or two synchronized, counterpropagating laser pulses are injected into a regenerative amplifier cavity and amplified by gain media which are pumped repetitively by electrical or optical means. The gain media excitation pulses are tailored to efficiently amplify the laser pulses during each transit. After the laser pulses have been amplified to the desired intensity level, they are either switched out of the cavity by some switch means, as for example an electro-optical device, for any well known laser end uses, or a target means may be injected into the regenerative amplifier cavity in such a way as to intercept simultaneously the counterpropagating laser pulses. One such well known end uses to which this invention is intended is for production of high density and temperature plasmas suitable for generating neutrons, ions and x-rays and for studying matter heated by high intensity laser radiation.

  1. Multiple excitation regenerative amplifier inertial confinement system

    DOEpatents

    George, V.E.; Haas, R.A.; Krupke, W.F.; Schlitt, L.G.

    1980-05-27

    The invention relates to apparatus and methods for producing high intensity laser radiation generation which is achieved through an optical amplifier-storage ring design. One or two synchronized, counterpropagating laser pulses are injected into a regenerative amplifier cavity and amplified by gain media which are pumped repetitively by electrical or optical means. The gain media excitation pulses are tailored to efficiently amplify the laser pulses during each transit. After the laser pulses have been amplified to the desired intensity level, they are either switched out of the cavity by some switch means, as for example an electro-optical device, for any well known laser end uses, or a target means may be injected into the regenerative amplifier cavity in such a way as to intercept simultaneously the counterpropagating laser pulses. One such well known end uses to which this invention is intended is for production of high density and temperature plasmas suitable for generating neutrons, ions and x-rays and for studying matter heated by high intensity laser radiation. 11 figs.

  2. Erich Regener - a forgotten cosmic ray pioneer

    NASA Astrophysics Data System (ADS)

    Carlson, Per; Watson, Alan

    2013-04-01

    In the 1930s the German physicist Erich Regener (1881-1955), did important work on the measurement of the rate production of ionisation in the atmosphere and deep under-water. He discovered, along with one of his students, Georg Pfotzer, the altitude at which the production of ionisation in the atmosphere reaches a maximum, often and misleadingly called the Pfotzer maximum. He was one of the first to estimate the energy density of cosmic rays, an estimate used by Baade and Zwicky to postulate that supernovae might be the source of cosmic rays. Yet Regener's name is little known largely because he was forced to take early retirement by the National Socialists in 1937 as his wife had Jewish ancestors. In this paper we review his work on cosmic rays and the subsequent influence that he had on the subject through his son, his son-in-law, his grandson and his students. He was nominated for the Nobel Prize in Physics by Schroedinger in 1938. He died in 1955 at the age of 73.

  3. Engineering growth factors for regenerative medicine applications.

    SciTech Connect

    Mitchell, Aaron C.; Briquez, Priscilla S.; Hubbell, Jeffrey A.; Cochran, Jennifer R.

    2016-01-15

    Growth factors are important morphogenetic proteins that instruct cell behavior and guide tissue repair and renewal. Although their therapeutic potential holds great promise in regenerative medicine applications, translation of growth factors into clinical treatments has been hindered by limitations including poor protein stability, low recombinant expression yield, and suboptimal efficacy. This review highlights current tools, technologies, and approaches to design integrated and effective growth factor-based therapies for regenerative medicine applications. The first section describes rational and combinatorial protein engineering approaches that have been utilized to improve growth factor stability, expression yield, biodistribution, and serum half-life, or alter their cell trafficking behavior or receptor binding affinity. The second section highlights elegant biomaterial-based systems, inspired by the natural extracellular matrix milieu, that have been developed for effective spatial and temporal delivery of growth factors to cell surface receptors. Although appearing distinct, these two approaches are highly complementary and involve principles of molecular design and engineering to be considered in parallel when developing optimal materials for clinical applications.

  4. Integrated regenerative fuel cell experimental evaluation

    NASA Technical Reports Server (NTRS)

    Martin, Ronald E.

    1990-01-01

    An experimental test program was conducted to investigate the performance characteristics of an integrated regenerative fuel cell (IRFC) concept. The IRFC consists of a separate fuel cell unit and electrolysis cell unit in the same structure, with internal storage of fuel cell product water and external storage of electrolysis cell produced hydrogen and oxygen. The fuel cell unit incorporates an enhanced Orbiter-type cell capable of improved performance at reduced weight. The electrolysis cell features a NiCo2O4 catalyst oxygen evolution eletrode with a porous Teflon cover to retard electrolyte loss. Six complete IRFC assemblies were assembled and performance tested at an operating temperature of 200 F (93.3 C) and reactant pressures up to 170 psia (117.2 n/cu cm) on IRFC No. 4. Anomalous pressure charge/discharge characteristics were encountered during performance evaluation. A reversible fuel cell incorporating a proprietary bi-functional oxygen electrode operated satisfactory at 200 F (93.3 C) at reactant pressures up to 50 psia (41.4 n/cu cm) as a regenerative fuel cell for one cycle, before developing an electrical short in the fuel cell mode. Electrolysis cell 300-hour endurance tests demonstrated the electrolyte retention capability of the electrode Teflon cover and the performance stability of the bi-functional oxygen electrode at high potential.

  5. Analysis of Regen Cooling in Rocket Combustors

    NASA Technical Reports Server (NTRS)

    Harper, Brent (Technical Monitor); Merkle, C. L.; Li, D.; Sankaran, V.

    2004-01-01

    The use of detailed CFD modeling for the description of cooling in rocket chambers is discussed. The overall analysis includes a complete three-dimensional analysis of the flow in the regenerative cooling passages, conjugate heat transfer in the combustor walls, and the effects of film cooling on the inside chamber. The results in the present paper omit the effects of film cooling and include only regen cooling and the companion conjugate heat transfer. The hot combustion gases are replaced by a constant temperature wall boundary condition. Load balancing for parallel cluster computations is ensured by using single-block unstructured grids for both fluids and solids, and by using a 'multiple physical zones' to account for differences in the number of equations. Validation of the method is achieved by comparing simple two-dimensional solutions with analytical results. Representative results for cooling passages are presents showing the effects of heat conduction in the copper walls with tube aspect ratios of 1.5:l.

  6. PRMT7 Preserves Satellite Cell Regenerative Capacity.

    PubMed

    Blanc, Roméo Sébastien; Vogel, Gillian; Chen, Taiping; Crist, Colin; Richard, Stéphane

    2016-02-16

    Regeneration of skeletal muscle requires the continued presence of quiescent muscle stem cells (satellite cells), which become activated in response to injury. Here, we report that whole-body protein arginine methyltransferase PRMT7(-/-) adult mice and mice conditionally lacking PRMT7 in satellite cells using Pax7-CreERT2 both display a significant reduction in satellite cell function, leading to defects in regenerative capacity upon muscle injury. We show that PRMT7 is preferentially expressed in activated satellite cells and, interestingly, PRMT7-deficient satellite cells undergo cell-cycle arrest and premature cellular senescence. These defects underlie poor satellite cell stem cell capacity to regenerate muscle and self-renew after injury. PRMT7-deficient satellite cells express elevated levels of the CDK inhibitor p21CIP1 and low levels of its repressor, DNMT3b. Restoration of DNMT3b in PRMT7-deficient cells rescues PRMT7-mediated senescence. Our findings define PRMT7 as a regulator of the DNMT3b/p21 axis required to maintain muscle stem cell regenerative capacity.

  7. Prevalence of significant liver disease in human immunodeficiency virus-infected patients exposed to Didanosine: A cross sectional study

    PubMed Central

    Logan, Sarah; Rodger, Alison; Maynard-Smith, Laura; O’Beirne, James; Fernandez, Thomas; Ferro, Filippo; Smith, Colette; Bhagani, Sanjay

    2016-01-01

    AIM To identify significant liver disease [including nodular regenerative hyperplasia (NRH)] in asymptomatic Didanosine (DDI) exposed human immunodeficiency virus (HIV) positive patients. METHODS Patients without known liver disease and with > 6 mo previous DDI use had liver stiffness assessed by transient elastography (TE). Those with alanine transaminase (ALT) above upper limit normal and/or TE > 7.65 kPa underwent ultrasound scan (U/S). Patients with: (1) abnormal U/S; or (2) elevated ALT plus TE > 7.65 kPa; or (3) TE > 9.4 kPa were offered trans-jugular liver biopsy (TJLB) with hepatic venous pressure gradient (HVPG) assessment. RESULTS Ninety-nine patients were recruited, median age 50 years (range 31-70), 81% male and 70% men who have sex with men. Ninety-five percent with VL < 50 copies on antiretroviral therapy with median CD4 count 639 IU/L. Median DDI exposure was 3.4 years (range 0.5-14.6). Eighty-one had a valid TE readings (interquartile range/score ratio < 0.3): 71 (88%) < 7.65 kPa, 6 (7%) 7.65-9.4 kPa and 4 (6%) > 9.4 kPa. Seventeen (17%) met criteria for TJLB, of whom 12 accepted. All had HVPG < 6 mmHg. Commonest histological findings were steatosis (n = 6), normal architecture (n = 4) and NRH (n = 2), giving a prevalence of previously undiagnosed NRH of 2% (95%CI: 0.55%, 7.0%). CONCLUSION A screening strategy based on TE, liver enzymes and U/S scan found a low prevalence of previously undiagnosed NRH in DDI exposed, asymptomatic HIV positive patients. Patients were more likely to have steatosis highlighting the increased risk of multifactorial liver disease in this population. PMID:28083085

  8. 78 FR 43889 - Synergizing Efforts in Standards Development for Cellular Therapies and Regenerative Medicine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-22

    ... Therapies and Regenerative Medicine Products; Public Workshop AGENCY: Food and Drug Administration, HHS... Development for Cellular Therapies and Regenerative Medicine Products.'' The purpose of the public workshop is... activities involving cellular therapies and regenerative medicine products. Date and Time: The...

  9. Regenerative medicine. Opportunities and challenges: a brief overview.

    PubMed

    Polak, Dame Julia

    2010-12-06

    Regenerative medicine is a new multi-disciplinary field aiming at the repair or replacement of disease body parts. The field is progressing at an unprecedented pace and although the opportunities are immense, many hurdles lie ahead. This brief review analyses the opportunities and challenges faced by regenerative medicine.

  10. Stem cells: intellectual property issues in regenerative medicine.

    PubMed

    Zachariades, Nicholas A

    2013-12-01

    The topic of stem cells for use in regenerative medicine, especially embryonic stem cells, inspires much debate, discussion, and outrage as it slices through the very core moral values of society. These social and moral issues have, in turn, resulted in government policies that have influenced the study of stem cells in regenerative medicine.

  11. Improved Round Trip Efficiency for Regenerative Fuel Cell Systems

    DTIC Science & Technology

    2011-04-04

    advanced membrane materials that enable higher efficiency electrolysis , substantially improving the practical energy density for regenerative fuel cell... electrolysis system for recharging the reactants, and reactant storage. These water- based energy storage systems have been shown to perform...catalyst materials will enable higher efficiency electrolysis , substantially improving the practical energy density for regenerative fuel cell applications

  12. State of the art: stem cells in equine regenerative medicine.

    PubMed

    Lopez, M J; Jarazo, J

    2015-03-01

    According to Greek mythology, Prometheus' liver grew back nightly after it was removed each day by an eagle as punishment for giving mankind fire. Hence, contrary to popular belief, the concept of tissue and organ regeneration is not new. In the early 20th century, cell culture and ex vivo organ preservation studies by Alexis Carrel, some with famed aviator Charles Lindbergh, established a foundation for much of modern regenerative medicine. While early beliefs and discoveries foreshadowed significant accomplishments in regenerative medicine, advances in knowledge within numerous scientific disciplines, as well as nano- and micromolecular level imaging and detection technologies, have contributed to explosive advances over the last 20 years. Virtually limitless preparations, combinations and applications of the 3 major components of regenerative medicine, namely cells, biomaterials and bioactive molecules, have created a new paradigm of future therapeutic options for most species. It is increasingly clear, however, that despite significant parallels among and within species, there is no 'one-size-fits-all' regenerative therapy. Likewise, a panacea has yet to be discovered that completely reverses the consequences of time, trauma and disease. Nonetheless, there is no question that the promise and potential of regenerative medicine have forever altered medical practices. The horse is a relative newcomer to regenerative medicine applications, yet there is already a large body of work to incorporate novel regenerative therapies into standard care. This review focuses on the current state and potential future of stem cells in equine regenerative medicine.

  13. C-cell hyperplasia and medullary thyroid microcarcinoma.

    PubMed

    Albores-Saavedra, J A; Krueger, J E

    2001-01-01

    Since the discovery of the thyroid C-cell, considerable progress has been made regarding its origin, function, and pathology. In this article an attempt is made to summarize and update our knowledge about physiologic or reactive C-cell hyperplasia, neoplastic C-cell hyperplasia (medullary carcinoma in situ), and medullary microcarcinoma. Seldom recognized preoperatively, physiologic C-cell hyperplasia is associated with inflammatory, metabolic, and neoplastic thyroid disorders as well as with hypercalcemia. However, the pathogenesis is still unclear. Although physiologic C-cell hyperplasia may progress to medullary carcinoma, the full malignant potential is unknown. Problems related to the definition of physiologic C-cell hyperplasia are discussed. Immunohistochemistry and quantitative analysis are required for the diagnosis. By contrast, C-cell hyperplasia associated with MEN II syndromes or familial medullary carcinoma can be diagnosed preoperatively in asymptomatic children or adolescents by the detection of germline mutations of the RET protooncogene. Morphologic and genetic abnormalities support the idea that C-cells in the familial form of C-cell hyperplasia are neoplastic and can be recognized with conventional stains. Therefore, the number of C-cells is irrelevant for the diagnosis. Medullary microcarcinoma is a neoplasm that measures < 1 cm. The sporadic variant is usually an incidental microscopic finding, whereas the familial form can be diagnosed by genetic testing. Its morphologic features and biologic behavior differ from those of larger medullary carcinomas. The frequency of medullary microcarcinoma will probably increase with the use of genetic testing.

  14. Stem Cells Applications in Regenerative Medicine and Disease Therapeutics

    PubMed Central

    2016-01-01

    Regenerative medicine, the most recent and emerging branch of medical science, deals with functional restoration of tissues or organs for the patient suffering from severe injuries or chronic disease. The spectacular progress in the field of stem cell research has laid the foundation for cell based therapies of disease which cannot be cured by conventional medicines. The indefinite self-renewal and potential to differentiate into other types of cells represent stem cells as frontiers of regenerative medicine. The transdifferentiating potential of stem cells varies with source and according to that regenerative applications also change. Advancements in gene editing and tissue engineering technology have endorsed the ex vivo remodelling of stem cells grown into 3D organoids and tissue structures for personalized applications. This review outlines the most recent advancement in transplantation and tissue engineering technologies of ESCs, TSPSCs, MSCs, UCSCs, BMSCs, and iPSCs in regenerative medicine. Additionally, this review also discusses stem cells regenerative application in wildlife conservation. PMID:27516776

  15. Stem Cells Applications in Regenerative Medicine and Disease Therapeutics.

    PubMed

    Mahla, Ranjeet Singh

    2016-01-01

    Regenerative medicine, the most recent and emerging branch of medical science, deals with functional restoration of tissues or organs for the patient suffering from severe injuries or chronic disease. The spectacular progress in the field of stem cell research has laid the foundation for cell based therapies of disease which cannot be cured by conventional medicines. The indefinite self-renewal and potential to differentiate into other types of cells represent stem cells as frontiers of regenerative medicine. The transdifferentiating potential of stem cells varies with source and according to that regenerative applications also change. Advancements in gene editing and tissue engineering technology have endorsed the ex vivo remodelling of stem cells grown into 3D organoids and tissue structures for personalized applications. This review outlines the most recent advancement in transplantation and tissue engineering technologies of ESCs, TSPSCs, MSCs, UCSCs, BMSCs, and iPSCs in regenerative medicine. Additionally, this review also discusses stem cells regenerative application in wildlife conservation.

  16. Evaluation strategy of regenerative braking energy for supercapacitor vehicle.

    PubMed

    Zou, Zhongyue; Cao, Junyi; Cao, Binggang; Chen, Wen

    2015-03-01

    In order to improve the efficiency of energy conversion and increase the driving range of electric vehicles, the regenerative energy captured during braking process is stored in the energy storage devices and then will be re-used. Due to the high power density of supercapacitors, they are employed to withstand high current in the short time and essentially capture more regenerative energy. The measuring methods for regenerative energy should be investigated to estimate the energy conversion efficiency and performance of electric vehicles. Based on the analysis of the regenerative braking energy system of a supercapacitor vehicle, an evaluation system for energy recovery in the braking process is established using USB portable data-acquisition devices. Experiments under various braking conditions are carried out. The results verify the higher efficiency of energy regeneration system using supercapacitors and the effectiveness of the proposed measurement method. It is also demonstrated that the maximum regenerative energy conversion efficiency can reach to 88%.

  17. Congenital adrenal hyperplasia: Treatment and outcomes.

    PubMed

    Kamoun, Mahdi; Feki, Mouna Mnif; Sfar, Mohamed Habib; Abid, Mohamed

    2013-10-01

    Congenital adrenal hyperplasia (CAH) describes a group of autosomal recessive disorders where there is impairment of cortisol biosynthesis. CAH due to 21-hydroxylase deficiency accounts for 95% of cases and shows a wide range of clinical severity. Glucocorticoid and mineralocorticoid replacement therapies are the mainstays of treatment of CAH. The optimal treatment for adults with CAH continues to be a challenge. Important long-term health issues for adults with CAH affect both men and women. These issues may either be due to the disease or to steroid treatment and may affect final height, fertility, cardiometabolic risk, bone metabolism, neuro-cognitive development and the quality-of-life. Patients with CAH should be regularly followed-up from childhood to adulthood by multidisciplinary teams who have knowledge of CAH. Optimal replacement therapy, close clinical and laboratory monitoring, early life-style interventions, early and regular fertility assessment and continuous psychological management are needed to improve outcome.

  18. Microwave Treatment of Prostate Cancer and Hyperplasia

    NASA Technical Reports Server (NTRS)

    Arndt, G. Dickey; Ngo, Phong; Carl, J. R.; Raffoul, George

    2005-01-01

    Microwave ablation in the form of microwave energy applied to a heart muscle by a coaxial catheter inserted in a vein in the groin area can be used to heat and kill diseased heart cells. A microwave catheter has been developed to provide deep myocardial ablation to treat ventricular tachycardia by restoring appropriate electrical activity within the heart and eliminating irregular heartbeats. The resulting microwave catheter design, which is now being developed for commercial use in treating ventricular tachycardia, can be modified to treat prostate cancer and benign prostatic hyperplasia (BPH). Inasmuch as the occurrence of BPH is increasing currently 350,000 operations per year are performed in the United States alone to treat this condition this microwave catheter has significant commercial potential.

  19. Pseudoangiomatous stromal hyperplasia causing massive breast enlargement.

    PubMed

    Bourke, Anita Geraldine; Tiang, Stephen; Harvey, Nathan; McClure, Robert

    2015-10-16

    Pseudoangiomatous stromal hyperplasia (PASH) of the breast is a benign mesenchymal proliferative process, initially described by Vuitch et al. We report an unusual case of a 46-year-old woman who presented with a 6-week history of bilateral massive, asymmetrical, painful enlargement of her breasts, without a history of trauma. On clinical examination, both breasts were markedly enlarged and oedematous, but there were no discrete palpable masses. Preoperative image-guided core biopsies and surgery showed PASH. PASH is increasingly recognised as an incidental finding on image-guided core biopsy performed for screen detected lesions. There are a few reported cases of PASH presenting as rapid breast enlargement. In our case, the patient presented with painful, asymmetrical, massive breast enlargement. Awareness needs to be raised of this entity as a differential diagnosis in massive, painful breast enlargement.

  20. Pseudoepitheliomatous Hyperplasia: Relevance in Oral Pathology

    PubMed Central

    Sarangarajan, R; Vedam, V K Vaishnavi; Sivadas, G; Krishnaraj, R; Sarangarajan, Anuradha; Shanmugam, K T

    2015-01-01

    Pseudoepitheliomatous hyperplasia (PEH), a neglected entity by oral pathologist possesses utmost importance in the field of research. Of all the investigative challenges, PEH, a reactive epithelial proliferation is seen secondary to lesions with infectious, inflammatory, reactive, and degenerative origin. Small sized samples, incomplete excision, improper orientation, and dense inflammatory changes render diagnostic confront to the oral pathologist in exclusion of frankly invasive malignant lesions like squamous cell carcinoma from lesions exhibiting PEH. The diagnosis can occasionally be difficult as they mimic other lesions also, on clinic-pathological assessment. Thus, this article gives an insight regarding the various concepts of etiopathogenesis, histopathology, differential diagnosis, and malignant potential of PEH. A combined effort of a clinician and pathologist benefits every patient to rule out malignancy and render appropriate treatment as the only local conservative approach is essential to remove PEH associated lesions. PMID:26229388

  1. Saw palmetto and benign prostatic hyperplasia.

    PubMed

    Gong, Edward M; Gerber, Glenn S

    2004-01-01

    Benign prostatic hyperplasia (BPH) is a common health issue that affects 8% of all men at the age of 40, 60% of men in their 70s, and 90% of those greater than 80 years of age. One-fourth of these men will develop moderate to severe lower urinary tract symptoms that greatly affect their quality of life. Recent evidence suggests that the use of saw palmetto leads to improvements in urinary function for those suffering from BPH. The favorable comparison of saw palmetto with tamsulosin, a well-known first line agent in the treatment of urinary tract symptoms, demonstrates promise towards a beneficial effect of this herbal agent, with very few, if any, adverse effects. However, what degree of this beneficial activity is due to placebo effects is yet to be determined. In addition, the precise mechanism of action of saw palmetto in men with BPH remains unclear.

  2. Papillary endothelial hyperplasia (Masson's tumor) in children.

    PubMed

    Liné, A; Sanchez, J; Jayyosi, L; Birembaut, P; Ohl, X; Poli-Mérol, M-L; François, C

    2016-06-23

    The intravascular papillary endothelial hyperplasia (IPEH/Masson's tumor) is a rare benign tumor of the skin and subcutaneous vessels. We report, in four pediatric cases, clinical presentation, care (diagnostic and surgical) of Masson's tumor in children. Two boys (two years) and two girls (four and six years) showed a pain subcutaneous tumor (one to five centimeters). They were in the transverse abdominal muscle, between two metatarsals, at the front of thigh and in the axilla. Imaging performed (MRI, Doppler ultrasound) evoked either a hematoma, a lymphangioma or hemangioma. The indication for removal was selected from pain and/or parental concern. The diagnosis was histologically. A lesion persisted in residual form (incomplete initial resection), and is currently not scalable for eleven years.

  3. Risk stratification for benign prostatic hyperplasia.

    PubMed

    Zattoni, Fabio; Ficarra, Vincenzo; Novara, Giacomo

    2017-03-18

    Benign prostatic hyperplasia (BPH) represents an important public health problem in ageing men due to frequently associated lower urinary tract symptoms (LUTS), which may impair quality of life. BPH is also a progressive disease, mainly characterized by a worsening of LUTS over time, and in some patients by the occurrence of serious outcomes such as acute urinary retention and need for BPH-related surgery. The management of BPH and LUTS in men should move forward its focus on symptom control only. Indeed, the goals of therapy for BPH are not only to improve bothersome LUTS but also to identify those patients at risk of unfavourable outcomes in order to optimize their management and reduce complications. Risk stratification and tailored treatment should improve the reductions in both symptoms and the long-term consequences of BPH and BPH treatments. To do this, clinicians need to know possible factors that may support the develop of PBH and possible risks due to the BPH itself.

  4. Benign prostatic hyperplasia: clinical manifestations and evaluation.

    PubMed

    Santos Dias, José

    2012-12-01

    Benign prostatic hyperplasia (BPH) is a very common condition, related to aging and causing symptoms, called lower urinary tract symptoms. On account of its huge prevalence, it is important for clinicians who are involved in the management of patients with BPH to be aware of the very strict recommendations for BPH evaluation. In this article, we describe the different steps and procedures doctors should follow to evaluate these patients; symptoms and signs of BPH are reviewed, as well as the clinical evaluation steps and examinations available. The basic evaluation of the patients with BPH should include, according to the recommendations of the most relevant international guidelines, lower urinary tract symptoms evaluation with appropriate symptom scores, digital rectal examination, voiding charts, prostate-specific antigen and creatinine measurement, urinalysis, and imaging of the urinary tract.

  5. Neonatal screening for congenital adrenal hyperplasia.

    PubMed Central

    Cacciari, E; Balsamo, A; Cassio, A; Piazzi, S; Bernardi, F; Salardi, S; Cicognani, A; Pirazzoli, P; Zappulla, F; Capelli, M

    1983-01-01

    Capillary blood samples from 42930 infants born in the Italian region of Emilia-Romagna were collected for 17-hydroxyprogesterone radioimmunoassays on days 2, 3, 4, 5, 6, and 7, or between days 7 and 15 of life. A microfilter paper method modified from that of Pang et al.1 was used for this assay. Pathologic values of 17-hydroxyprogesterone were found in 5 infants giving an incidence in this homogeneous Caucasian population of 1:8586. We also investigated 17-hydroxyprogesterone values in relation to the day of sampling and the possible correlation between 17-hydroxyprogesterone values and birthweight and gestational age. We concluded that neonatal screening for congenital adrenal hyperplasia caused by 21-hydroxylase deficiency was possible by this method and that the infants' maturity and the particular day of collection of the samples affect the values but not the validity of the screening. PMID:6639129

  6. Optimizing the management of benign prostatic hyperplasia

    PubMed Central

    Elterman, Dean S.; Kaplan, Steven A.

    2012-01-01

    One of the challenges facing primary care physicians and specialists as the population ages is the management of lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH). While as many as 18% of men in their 40s report bother from an enlarged prostate, that figure rises dramatically, whereby 50% of men in their 50s and 90% of men in their 90s will complain of bothersome symptoms related to an enlarged prostate. Studies have shown that BPH is a progressive disease, which if left untreated can result in worsening of symptoms, acute urinary retention and renal failure. Until about 20 years ago the only management option available to urologists was surgery. In the early 1990s medical therapy emerged as the predominant treatment for BPH. Therapy may be tailored to target symptoms and progression of disease. PMID:22496710

  7. Solar Airplanes and Regenerative Fuel Cells

    NASA Technical Reports Server (NTRS)

    Bents, David J.

    2007-01-01

    A solar electric aircraft with the potential to "fly forever" has captured NASA's interest, and the concept for such an aircraft was pursued under Aeronautics Environmental Research Aircraft and Sensor Technology (ERAST) project. Feasibility of this aircraft happens to depend on the successful development of solar power technologies critical to NASA's Exploration Initiatives; hence, there was widespread interest throughout NASA to bring these technologies to a flight demonstration. The most critical is an energy storage system to sustain mission power during night periods. For the solar airplane, whose flight capability is already limited by the diffuse nature of solar flux and subject to latitude and time of year constraints, the feasibility of long endurance flight depends on a storage density figure of merit better than 400-600 watt-hr per kilogram. This figure of merit is beyond the capability of present day storage technologies (other than nuclear) but may be achievable in the hydrogen-oxygen regenerative fuel cell (RFC). This potential has led NASA to undertake the practical development of a hydrogen-oxygen regenerative fuel cell, initially as solar energy storage for a high altitude UAV science platform but eventually to serve as the primary power source for NASAs lunar base and other planet surface installations. Potentially the highest storage capacity and lowest weight of any non-nuclear device, a flight-weight RFC aboard a solar-electric aircraft that is flown continuously through several successive day-night cycles will provide the most convincing demonstration that this technology's widespread potential has been realized. In 1998 NASA began development of a closed cycle hydrogen oxygen PEM RFC under the Aeronautics Environmental Research Aircraft and Sensor Technology (ERAST) project and continued its development, originally for a solar electric airplane flight, through FY2005 under the Low Emissions Alternative Power (LEAP) project. Construction of

  8. Fibroadenoma with "immature-like" type of usual ductal hyperplasia.

    PubMed

    Bezić, Joško; Karaman, Ivana; Kunac, Nenad

    2016-01-01

    We herein report a case of the breast fibroadenoma with foci of so-called immature variant of the conventional ductal hyperplasia. This type of usual ductal hyperplasia is histologically characterised by encircling intraductal proliferation of large cells with pale to amphophilic cytoplasm and large nuclei which vary in shape and in staining quality of the chromatin. We showed here, using the cytokeratin immunohistochemistry, that the proliferating cells were not of immature but rather mature immunohistochemical phenotype. Because of the presented discordance between immature histology and mature immunohistological profile we suggest that this rare type of usual ductal hyperplasia should be called "immature-like".

  9. Liposomes in tissue engineering and regenerative medicine

    PubMed Central

    Monteiro, Nelson; Martins, Albino; Reis, Rui L.; Neves, Nuno M.

    2014-01-01

    Liposomes are vesicular structures made of lipids that are formed in aqueous solutions. Structurally, they resemble the lipid membrane of living cells. Therefore, they have been widely investigated, since the 1960s, as models to study the cell membrane, and as carriers for protection and/or delivery of bioactive agents. They have been used in different areas of research including vaccines, imaging, applications in cosmetics and tissue engineering. Tissue engineering is defined as a strategy for promoting the regeneration of tissues for the human body. This strategy may involve the coordinated application of defined cell types with structured biomaterial scaffolds to produce living structures. To create a new tissue, based on this strategy, a controlled stimulation of cultured cells is needed, through a systematic combination of bioactive agents and mechanical signals. In this review, we highlight the potential role of liposomes as a platform for the sustained and local delivery of bioactive agents for tissue engineering and regenerative medicine approaches. PMID:25401172

  10. Regenerative medicine: the emergence of an industry.

    PubMed

    Nerem, Robert M

    2010-12-06

    Over the last quarter of a century there has been an emergence of a tissue engineering industry, one that has now evolved into the broader area of regenerative medicine. There have been 'ups and downs' in this industry; however, it now appears to be on a track that may be described as 'back to the future'. The latest data indicate that for 2007 the private sector activity in the world for this industry is approaching $2.5 billion, with 167 companies/business units and more than 6000 employee full time equivalents. Although small compared with the medical device and also the pharmaceutical industries, these numbers are not insignificant. Thus, there is the indication that this industry, and the related technology, may still achieve its potential and address the needs of millions of patients worldwide, in particular those with needs that currently are unmet.

  11. Why regenerative medicine needs an extracellular matrix.

    PubMed

    Prestwich, Glenn D; Healy, Kevin E

    2015-01-01

    Regenerative medicine is now coming of age. Many attempts at cell therapy have failed to show significant efficacy, and the umbrella term 'stem cell therapy' is perceived in some quarters as hype or just expensive and unnecessary medical tourism. Here we present a short editorial in three parts. First, we examine the importance of using a semisynthetic extracellular matrix (ECM) mimetic, or sECM, to deliver and retain therapeutic cells at the site of administration. Second, we describe one approach in which biophysical and biochemical properties are tailored to each tissue type, which we call "design for optimal functionality." Third, we describe an alternative approach to sECM design and implementation, called "design for simplicity," in which a deconstructed, minimalist sECM is employed and biology is allowed to perform the customization in situ. We opine that an sECM, whether minimal or instructive, is an essential contributor to improve the outcomes of cell-based therapies.

  12. The international translational regenerative medicine center.

    PubMed

    Alexis, Mardi de Veuve; Grinnemo, Karl-Henrik; Jove, Richard

    2012-11-01

    The International Translational Regenerative Medicine Center, an organizing sponsor of the World Stem Cell Summit 2012, is a global initiative established in 2011 by founding partners Karolinska Institutet (Stockholm, Sweden) and Beckman Research Institute at City of Hope (CA, USA) with a mission to facilitate the acceleration of translational research and medicine on a global scale. Karolinska Institutet, home of the Nobel Prize in Medicine or Physiology, is one of the most prestigious medical research institutions in the world. The Beckman Research Institute/City of Hope is ranked among the leading NIH-designated comprehensive cancer research and treatment institutions in the USA, has the largest academic GMP facility and advanced drug discovery capability, and is a pioneer in diabetes research and treatment.

  13. Regenerative Medicine Strategies for Esophageal Repair

    PubMed Central

    Londono, Ricardo

    2015-01-01

    Pathologies that involve the structure and/or function of the esophagus can be life-threatening. The esophagus is a complex organ comprising nonredundant tissue that does not have the ability to regenerate. Currently available interventions for esophageal pathology have limited success and are typically associated with significant morbidity. Hence, there is currently an unmet clinical need for effective methods of esophageal repair. The present article presents a review of esophageal disease along with the anatomic and functional consequences of each pathologic process, the shortcomings associated with currently available therapies, and the latest advancements in the field of regenerative medicine with respect to strategies for esophageal repair from benchtop to bedside. PMID:25813694

  14. A regenerative approach towards mucosal fenestration closure.

    PubMed

    Gandi, Padma; Anumala, Naveen; Reddy, Amarender; Chandra, Rampalli Viswa

    2013-06-06

    Mucosal fenestration is an opening or an interstice through the oral mucosa. A lesion which occurs with greater frequency than generally realised, its occurrence is attributed to a myriad of causes. Mucogingival procedures including connective tissue grafts, free gingival grafts and lateral pedicle grafts are generally considered to be the treatment of choice in the closure of a mucosal fenestration. More often, these procedures are performed in conjunction with other procedures such as periradicular surgery and with bone grafts. However, the concomitant use of gingival grafts and bone grafts in mucosal fenestrations secondary to infections in sites exhibiting severe bone loss is highly debatable. In this article, we report two cases of mucosal fenestrations secondary to trauma and their management by regenerative periodontal surgery with the placement of guided tissue regeneration membrane and bone graft. The final outcome was a complete closure of the fenestration in both the cases.

  15. Heart Valve Replacements with Regenerative Capacity

    PubMed Central

    Dijkman, Petra E.; Fioretta, Emanuela S.; Frese, Laura; Pasqualini, Francesco S.; Hoerstrup, Simon P.

    2016-01-01

    The incidence of severe valvular dysfunctions (e.g., stenosis and insufficiency) is increasing, leading to over 300,000 valves implanted worldwide yearly. Clinically used heart valve replacements lack the capacity to grow, inherently requiring repetitive and high-risk surgical interventions during childhood. The aim of this review is to present how different tissue engineering strategies can overcome these limitations, providing innovative valve replacements that proved to be able to integrate and remodel in pre-clinical experiments and to have promising results in clinical studies. Upon description of the different types of heart valve tissue engineering (e.g., in vitro, in situ, in vivo, and the pre-seeding approach) we focus on the clinical translation of this technology. In particular, we will deepen the many technical, clinical, and regulatory aspects that need to be solved to endure the clinical adaptation and the commercialization of these promising regenerative valves. PMID:27721704

  16. [Cell transplant and regenerative stem cell therapy].

    PubMed

    Prosper, F

    2008-01-01

    The derivation of the first human embryonic stem cell lines as well as the notion of the unexpected plasticity and potential of the adult stem cells has significantly impacted the biomedical research. Many of the tissues long believe to lack any regenerative capacity has demonstrated otherwise. Patients alike physicians expectations for treatment of incurable diseases have also fuelled this field and in occasions have led to unrealistic expectations. In the next pages I review some of the tissue specific stem cells that have been used either in preclinical models or even in clinical research. Despite the effort of numerous investigators, more questions that answers remain in the field of cell therapy and only careful and independent -not biased- research will allow us to translate some of this findings into clinical application.

  17. Genetic engineering for skeletal regenerative medicine.

    PubMed

    Gersbach, Charles A; Phillips, Jennifer E; García, Andrés J

    2007-01-01

    The clinical challenges of skeletal regenerative medicine have motivated significant advances in cellular and tissue engineering in recent years. In particular, advances in molecular biology have provided the tools necessary for the design of gene-based strategies for skeletal tissue repair. Consequently, genetic engineering has emerged as a promising method to address the need for sustained and robust cellular differentiation and extracellular matrix production. As a result, gene therapy has been established as a conventional approach to enhance cellular activities for skeletal tissue repair. Recent literature clearly demonstrates that genetic engineering is a principal factor in constructing effective methods for tissue engineering approaches to bone, cartilage, and connective tissue regeneration. This review highlights this literature, including advances in the development of efficacious gene carriers, novel cell sources, successful delivery strategies, and optimal target genes. The current status of the field and the challenges impeding the clinical realization of these approaches are also discussed.

  18. Regenerative medicine: the emergence of an industry

    PubMed Central

    Nerem, Robert M.

    2010-01-01

    Over the last quarter of a century there has been an emergence of a tissue engineering industry, one that has now evolved into the broader area of regenerative medicine. There have been ‘ups and downs’ in this industry; however, it now appears to be on a track that may be described as ‘back to the future’. The latest data indicate that for 2007 the private sector activity in the world for this industry is approaching $2.5 billion, with 167 companies/business units and more than 6000 employee full time equivalents. Although small compared with the medical device and also the pharmaceutical industries, these numbers are not insignificant. Thus, there is the indication that this industry, and the related technology, may still achieve its potential and address the needs of millions of patients worldwide, in particular those with needs that currently are unmet. PMID:20843840

  19. Carbohydrate engineered cells for regenerative medicine.

    PubMed

    Du, Jian; Yarema, Kevin J

    2010-06-15

    Carbohydrates are integral components of the stem cell niche on several levels; proteoglycans are a major constituent of the extracellular matrix (ECM) surrounding a cell, glycosoaminoglycans (GAGs) help link cells to the ECM and the neighboring cells, and small but informationally-rich oligosaccharides provide a "sugar code" that identifies each cell and provides it with unique functions. This article samples roles that glycans play in development and then describes how metabolic glycoengineering - a technique where monosaccharide analogs are introduced into the metabolic pathways of a cell and are biosynthetically incorporated into the glycocalyx - is overcoming many of the long-standing barriers to manipulating carbohydrates in living cells and tissues and is becoming an intriguing new tool for tissue engineering and regenerative medicine.

  20. Carbohydrate Engineered Cells for Regenerative Medicine

    PubMed Central

    Du, Jian; Yarema, Kevin J.

    2010-01-01

    Carbohydrates are integral components of the stem cell niche on several levels; proteoglycans are a major constituent of the extracellular matrix (ECM) surrounding a cell, glycosoaminoglycans (GAGs) help link cells to the ECM and the neighboring cells, and small but informationally-rich oligosaccharides provide a “sugar code” that identifies each cell and provides it with unique functions. This article samples roles that glycans play in development and then describes how metabolic glycoengineering – a technique where monosaccharide analogs are introduced into the metabolic pathways of a cell and are biosynthetically incorporated into the glycocalyx – is overcoming many of the long-standing barriers to manipulating carbohydrates in living cells and tissues and is becoming an intriguing new tool for tissue engineering and regenerative medicine. PMID:20117158

  1. Power Management in Regenerative Life Support Systems

    NASA Technical Reports Server (NTRS)

    Crawford, Sekou; Pawlowski, Christopher; Finn, Cory; Mead, Susan C. (Technical Monitor)

    1999-01-01

    Effective management of power can reduce the cost of launch and operation of regenerative life support systems. Variations in power may be quite severe and may manifest as surges or spikes, While the power plant may have some ability to deal with these variations, with batteries for example, over-capacity is expensive and does nothing to address the fundamental issue of excessive demand. Because the power unit must be sized to accommodate the largest demand, avoiding power spikes has the potential to reduce the required size of the power plant while at the same time increasing the dependability of the system. Scheduling of processors can help to reduce potential power spikes. However, not all power-consuming equipment is easily scheduled. Therefore, active power management is needed to further decrease the risk of surges or spikes. We investigate the use of a hierarchical scheme to actively manage power for a model of a regenerative life support system. Local level controllers individually determine subsystem power usage. A higher level controller monitors overall system power and detects surges or spikes. When a surge condition is detected, the higher level controller conducts an 'auction' and describes subsystem power usage to re-allocate power. The result is an overall reduction in total power during a power surge. The auction involves each subsystem making a 'bid' to buy or sell power based on local needs. However, this re-allocation cannot come at the expense of life support function. To this end, participation in the auction is restricted to those processes meeting certain tolerance constraints. These tolerances represent acceptable limits within which system processes can be operated. We present a simulation model and discuss some of our results.

  2. Regenerative Blower for EVA Suit Ventilation Fan

    NASA Technical Reports Server (NTRS)

    Paul, Heather; Izenson, Mike; Chen, Weibo

    2008-01-01

    Portable life support systems in future space suits will include a ventilation subsystem driven by a dedicated fan. This ventilation fan must meet challenging requirements for pressure rise, flow rate, efficiency, size, safety, and reliability. This paper describes research and development that showed the feasibility of a regenerative blower that is uniquely suited to meet these requirements. We proved feasibility through component tests, blower tests, and design analysis. Based on the requirements for the Constellation Space Suit ventilation fan, we designed the critical elements of the blower. We measured the effects of key design parameters on blower performance using separate effects tests, and used the results of these tests to design a regenerative blower that will meet the ventilation fan requirements. We assembled a proof-of-concept blower and measured its performance at low pressures that simulate a PLSS environment. We obtained head/flow performance curves over a range of operating speeds, identified the maximum efficiency point for the blower, and used these results to specify the design and operating conditions for the ventilation fan. We designed a compact motor that can drive the blower under all anticipated operating requirements and operate with high efficiency during normal operation. We identified materials for the blower that will enhance safety for operation in a lunar environment. We produced a solid model that illustrates the final design. The proof-of-concept blower produced the flow rate and pressure rise needed for the CSSS ventilation subsystem while running at 5400 rpm and consuming only 9 W of electric power and using a non-optimized, commercial motor and controller and inefficient bearings. Scaling the test results to a complete design shows that a lightweight, compact, reliable, and low power blower can meet the performance requirements for future PLSSs.

  3. Heat cascading regenerative sorption heat pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor)

    1995-01-01

    A simple heat cascading regenerative sorption heat pump process with rejected or waste heat from a higher temperature chemisorption circuit (HTCC) powering a lower temperature physisorption circuit (LTPC) which provides a 30% total improvement over simple regenerative physisorption compression heat pumps when ammonia is both the chemisorbate and physisorbate, and a total improvement of 50% or more for LTPC having two pressure stages. The HTCC contains ammonia and a chemisorbent therefor contained in a plurality of canisters, a condenser-evaporator-radiator system, and a heater, operatively connected together. The LTPC contains ammonia and a physisorbent therefor contained in a plurality of compressors, a condenser-evaporator-radiator system, operatively connected together. A closed heat transfer circuit (CHTC) is provided which contains a flowing heat transfer liquid (FHTL) in thermal communication with each canister and each compressor for cascading heat from the HTCC to the LTPC. Heat is regenerated within the LTPC by transferring heat from one compressor to another. In one embodiment the regeneration is performed by another CHTC containing another FHTL in thermal communication with each compressor. In another embodiment the HTCC powers a lower temperature ammonia water absorption circuit (LTAWAC) which contains a generator-absorber system containing the absorbent, and a condenser-evaporator-radiator system, operatively connected together. The absorbent is water or an absorbent aqueous solution. A CHTC is provided which contains a FHTL in thermal communication with the generator for cascading heat from the HTCC to the LTAWAC. Heat is regenerated within the LTAWAC by transferring heat from the generator to the absorber. The chemical composition of the chemisorbent is different than the chemical composition of the physisorbent, and the absorbent. The chemical composition of the FHTL is different than the chemisorbent, the physisorbent, the absorbent, and ammonia.

  4. Rejuvenation: an integrated approach to regenerative medicine.

    PubMed

    Kang, Y James; Zheng, Lily

    2013-12-01

    The word "rejuvenate" found in the Merriam-Webster dictionary is (1) to make young or youthful again: give new vigor to, and (2) to restore to an original or new state. Regenerative medicine is the process of creating living, functional tissues to repair or replace tissue or organ function lost due to age, disease, damage, or congenital defects. To accomplish this, approaches including transplantation, tissue engineering, cell therapy, and gene therapy are brought into action. These all use exogenously prepared materials to forcefully mend the failed organ. The adaptation of the materials in the host and their integration into the organ are all uncertain. It is a common sense that tissue injury in the younger is easily repaired and the acute injury is healed better and faster. Why does the elder have a diminished capacity of self-repairing, or why does chronic injury cause the loss of the self-repairing capacity? There must be some critical elements that are involved in the repair process, but are suppressed in the elder or under the chronic injury condition. Rejuvenation of the self-repair mechanism would be an ideal solution for functional recovery of the failed organ. To achieve this, it would involve renewal of the injury signaling, reestablishment of the communication and transportation system, recruitment of the materials for repairing, regeneration of the failed organ, and rehabilitation of the renewed organ. It thus would require a comprehensive understanding of developmental biology and a development of new approaches to activate the critical players to rejuvenate the self-repair mechanism in the elder or under chronic injury condition. Efforts focusing on rejuvenation would expect an alternative, if not a better, accomplishment in the regenerative medicine.

  5. The TMI Regenerative Solid Oxide Fuel Cell

    NASA Technical Reports Server (NTRS)

    Cable, Thomas L.; Ruhl, Robert C.; Petrik, Michael

    1996-01-01

    Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. Systems generally consist of photovoltaic solar arrays which operate (during sunlight cycles) to provide system power and regenerate fuel (hydrogen) via water electrolysis and (during dark cycles) fuel cells convert hydrogen into electricity. Common configurations use two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Reliability, power to weight and power to volume ratios could be greatly improved if both power production (fuel cells) and power storage (electrolysis) functions can be integrated into a single unit. The solid oxide fuel cell (SOFC) based design integrates fuel cell and electrolyzer functions and potentially simplifies system requirements. The integrated fuel cell/electrolyzer design also utilizes innovative gas storage concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H20 electrode (SOFC anode/electrolyzer cathode) materials for regenerative fuel cells. Tests have shown improved cell performance in both fuel and electrolysis modes in reversible fuel cell tests. Regenerative fuel cell efficiencies, ratio of power out (fuel cell mode) to power in (electrolyzer mode), improved from 50 percent using conventional electrode materials to over 80 percent. The new materials will allow a single SOFC system to operate as both the electolyzer and fuel cell. Preliminary system designs have also been developed to show the technical feasibility of using the design for space applications requiring high energy storage efficiencies and high specific energy. Small space systems also have potential for dual-use, terrestrial applications.

  6. Materials science tools for regenerative medicine

    NASA Astrophysics Data System (ADS)

    Richardson, Wade Nicholas

    Regenerative therapies originating from recent technological advances in biology could revolutionize medicine in the coming years. In particular, the advent of human pluripotent stem cells (hPSCs), with their ability to become any cell in the adult body, has opened the door to an entirely new way of treating disease. However, currently these medical breakthroughs remain only a promise. To make them a reality, new tools must be developed to surmount the new technical hurdles that have arisen from dramatic departure from convention that this field represents. The collected work presented in this dissertation covers several projects that seek to apply the skills and knowledge of materials science to this tool synthesizing effort. The work is divided into three chapters. The first deals with our work to apply Raman spectroscopy, a tool widely used for materials characterization, to degeneration in cartilage. We have shown that Raman can effectively distinguish the matrix material of healthy and diseased tissue. The second area of work covered is the development of a new confocal image analysis for studying hPSC colonies that are chemical confined to uniform growth regions. This tool has important application in understanding the heterogeneity that may slow the development of hPSC -based treatment, as well as the use of such confinement in the eventually large-scale manufacture of hPSCs for therapeutic use. Third, the use of structural templating in tissue engineering scaffolds is detailed. We have utilized templating to tailor scaffold structures for engineering of constructs mimicking two tissues: cartilage and lung. The work described here represents several important early steps towards large goals in regenerative medicine. These tools show a great deal of potential for accelerating progress in this field that seems on the cusp of helping a great many people with otherwise incurable disease.

  7. New Developments in Our Understanding of Neointimal Hyperplasia.

    PubMed

    Lee, Timmy; Ul Haq, Naveed

    2015-11-01

    The vascular access remains the lifeline for the hemodialysis patient. The most common etiology of vascular access dysfunction is venous stenosis at the vein-artery anastomosis in arteriovenous fistula and at the vein-graft anastomosis in arteriovenous grafts (AVG). This stenotic lesion is typically characterized on histology as aggressive venous neointimal hyperplasia in both arteriovenous fistula and AVG. In recent years, we have advanced our knowledge and understanding of neointimal hyperplasia in vascular access and begun testing several novel therapies. This article will (1) review recent developments in our understanding of the pathophysiology of neointimal hyperplasia development in AVG and fistula failure, (2) discuss atypical factors leading to neointimal hyperplasia development, (3) highlight key novel therapies that have been evaluated in clinical trials, and (4) discuss future opportunities and challenges to improve our understanding of vascular access dysfunction and translate this knowledge into novel and innovative therapies.

  8. A patient with congenital hypertrichosis, gum hyperplasia and macromastia.

    PubMed

    Sood, A; Garg, R K; Saily, R; Dash, R J

    2000-05-01

    A syndrome of congenital hypertrichosis, hirsutism, gum hyperplasia and macromastia is described. The patient was demonstrated to have mild hyperinsulinemia with normal oral glucose tolerance test. This is the second such patient reported in the literature.

  9. Axon and muscle spindle hyperplasia in the myostatin null mouse.

    PubMed

    Elashry, Mohamed I; Otto, Anthony; Matsakas, Antonios; El-Morsy, Salah E; Jones, Lisa; Anderson, Bethan; Patel, Ketan

    2011-02-01

    Germline deletion of the myostatin gene results in hyperplasia and hypertrophy of the tension-generating (extrafusal) fibres in skeletal muscle. As this gene is expressed predominantly in myogenic tissues it offers an excellent model with which to investigate the quantitative relationship between muscle and axonal development. Here we show that skeletal muscle hyperplasia in myostatin null mouse is accompanied by an increase in nerve fibres in major nerves of both the fore- and hindlimbs. We show that axons within these nerves undergo hypertrophy. Furthermore, we provide evidence that the age-related neural atrophic process is delayed in the absence of myostatin. Finally, we show that skeletal muscle hyperplasia in the myostatin null mouse is accompanied by an increase in the number of muscle spindles (also called stretch receptors or proprioceptors). However, our work demonstrates that the mechanisms regulating intrafusal fibre hyperplasia and hypertrophy differ from those that control the aetiology of extrafusal fibres.

  10. A giant prostatic hyperplasia treated by open surgery

    PubMed Central

    Ogawa, Soichiro; Manome, Masahiko; Yabe, Michihiro; Kuma, Yoshinobu; Yamaoka, Masaaki; Sato, Yuichi; Akaihata, Hidenori; Oguro, Toshiki; Kataoka, Masao; Kumagai, Shin; Kojima, Yoshiyuki

    2012-01-01

    We report a rare case of giant prostatic hyperplasia treated by open surgery. A 70-year-old man was suffering from macrohematuria. Computed tomography revealed a markedly enlarged prostate measuring 580 mL. The serum prostate-specific antigen level was 9.430 ng/mL. Prostatic biopsy showed benign prostatic hyperplasia. We perfomed retropubic open prostatectomy, since macrohematuria continued and he was also suffering from lower urinary tract symptoms. The adenoma was completely enucleated in one piece. The removed specimen was 13 × 11 × 6 cm in size and weighed 475 g. Histological examination also demonstrated prostatic fibromuscular hyperplasia. This is the 15th-heaviest adenoma ever reported in English-language journals. Transurethral surgical techniques or other minimally invasive approaches are performed for patients with small to medium-sized prostates. However, open surgery is recommended for markedly enlarged prostatic hyperplasia. PMID:23271919

  11. Ortho-surgical management of condylar hyperplasia: Rare case reports.

    PubMed

    Singh, Virendra; Verma, Ajay; Attresh, Gyanander; Batra, Jitender

    2014-01-01

    Condylar hyperplasia of the mandible is a clinical condition of over-development and growth because of excessive cellular growth of one condylar part of the mandible leading to facial asymmetry, mandibular deviation and enlargement of condyle. The elongation of the condylar neck in turn leads to malocclusion and articular dysfunction. In the past the interceptive and corrective procedures of growth and deformity in condylar hyperplasia were either condylectomy or high condylotomy. However, the deformity ceases after growth is completed. Therefore, other surgical procedures have to be undertaken to correct the manifested deformity of condylar hyperplasia. Further it has to be stressed that no single procedure can completely correct the deformity. So in addition to condylectomy, other orthognathic surgical procedures both on body and ramus and also on maxilla can be undertaken to correct the canting of occlusion. Two rare cases of unilateral hyperplasia encountered in our hospital are presented which required different lines of treatment.

  12. A review of the regenerative endodontic treatment procedure

    PubMed Central

    Lee, Bin-Na; Moon, Jong-Wook; Chang, Hoon-Sang; Hwang, In-Nam; Oh, Won-Mann

    2015-01-01

    Traditionally, apexification has been used to treat immature permanent teeth that have lost pulp vitality. This technique promotes the formation of an apical barrier to close the open apex so that the filling materials can be confined to the root canal. Because tissue regeneration cannot be achieved with apexification, a new technique called regenerative endodontic treatment was presented recently to treat immature permanent teeth. Regenerative endodontic treatment is a treatment procedure designed to replace damaged pulp tissue with viable tissue which restores the normal function of the pulp-dentin structure. After regenerative endodontic treatment, continued root development and hard tissue deposition on the dentinal wall can occur under ideal circumstances. However, it is difficult to predict the result of regenerative endodontic treatment. Therefore, the purpose of this study was to summarize multiple factors effects on the result of regenerative endodontic treatment in order to achieve more predictable results. In this study, we investigated the features of regenerative endodontic treatment in comparison with those of other pulp treatment procedures and analyzed the factors that have an effect on regenerative endodontic treatment. PMID:26295020

  13. Focal epithelial hyperplasia. A rare disease in our area.

    PubMed

    Segura-Saint-Gerons, Rafael; Toro-Rojas, Mariano; Ceballos-Salobreña, Alejandro; Aparicio-Soria, Jose Luis; Fuentes-Vaamonde, Helena

    2005-01-01

    Focal epithelial hyperplasia is a benign, asymptomatic disease, occurring with very low frequency within our population. It appears as papules, principally on the lower lip, although it can also be found on the retro-commissural mucosa and tongue, and less frequently on the upper lip, gingiva and palate. We present the clinical case of a 9-year-old Saharan girl with lesions that clinically and histologically corresponded to a focal epithelial hyperplasia.

  14. Dedifferentiation, transdifferentiation, and reprogramming: future directions in regenerative medicine.

    PubMed

    Eguizabal, Cristina; Montserrat, Nuria; Veiga, Anna; Izpisua Belmonte, Juan Carlos

    2013-01-01

    The main goal of regenerative medicine is to replace damaged tissue. To do this it is necessary to understand in detail the whole regeneration process including differentiated cells that can be converted into progenitor cells (dedifferentiation), cells that can switch into another cell type (transdifferentiation), and somatic cells that can be induced to become pluripotent cells (reprogramming). By studying the regenerative processes in both nonmammal and mammal models, natural or artificial processes could underscore the molecular and cellular mechanisms behind these phenomena and be used to create future regenerative strategies for humans.

  15. The Quest toward limb regeneration: a regenerative engineering approach

    PubMed Central

    Laurencin, Cato T.; Nair, Lakshmi S.

    2016-01-01

    The Holy Grail to address the clinical grand challenge of human limb loss is to develop innovative strategies to regrow the amputated limb. The remarkable advances in the scientific understanding of regeneration, stem cell science, material science and engineering, physics and novel surgical approaches in the past few decades have provided a regenerative tool box to face this grand challenge and address the limitations of human wound healing. Here we discuss the convergence approach put forward by the field of Regenerative Engineering to use the regenerative tool box to design and develop novel translational strategies to limb regeneration. PMID:27047679

  16. Regenerative endodontics: barriers and strategies for clinical translation.

    PubMed

    Mao, Jeremy J; Kim, Sahng G; Zhou, Jian; Ye, Ling; Cho, Shoko; Suzuki, Takahiro; Fu, Susan Y; Yang, Rujing; Zhou, Xuedong

    2012-07-01

    Regenerative endodontics has encountered substantial challenges toward clinical translation. The adoption by the American Dental Association of evoked pulp bleeding in immature permanent teeth is an important step for regenerative endodontics. However, there is no regenerative therapy for most endodontic diseases. Simple recapitulation of cell therapy and tissue engineering strategies that are under development for other organ systems has not led to clinical translation in regeneration endodontics. Recent work using novel biomaterial scaffolds and growth factors that orchestrate the homing of host endogenous cells represents a departure from traditional cell transplantation approaches and may accelerate clinical translation.

  17. Adaptive controller for regenerative and friction braking system

    DOEpatents

    Davis, R.I.

    1990-10-16

    A regenerative and friction braking system for a vehicle having one or more road wheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerative brakes operatively connected with the road wheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerative braking subsystems so that maximum brake torques sustainable by the road wheels of the vehicle without skidding or slipping will not be exceeded. 8 figs.

  18. Biomolecule delivery to engineer the cellular microenvironment for regenerative medicine.

    PubMed

    Bishop, Corey J; Kim, Jayoung; Green, Jordan J

    2014-07-01

    To realize the potential of regenerative medicine, controlling the delivery of biomolecules in the cellular microenvironment is important as these factors control cell fate. Controlled delivery for tissue engineering and regenerative medicine often requires bioengineered materials and cells capable of spatiotemporal modulation of biomolecule release and presentation. This review discusses biomolecule delivery from the outside of the cell inwards through the delivery of soluble and insoluble biomolecules as well as from the inside of the cell outwards through gene transfer. Ex vivo and in vivo therapeutic strategies are discussed, as well as combination delivery of biomolecules, scaffolds, and cells. Various applications in regenerative medicine are highlighted including bone tissue engineering and wound healing.

  19. Adaptive controller for regenerative and friction braking system

    SciTech Connect

    Davis, Roy I.

    1990-01-01

    A regenerative and friction braking system for a vehicle having one or more roadwheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerative brakes operatively connected with the roadwheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerative braking subsystems so that maximum brake torques sustainable by the roadwheels of the vehicle without skidding or slipping will not be exceeded.

  20. Cinacalcet HCl prevents development of parathyroid gland hyperplasia and reverses established parathyroid gland hyperplasia in a rodent model of CKD

    PubMed Central

    Miller, Gerald; Davis, James; Shatzen, Edward; Colloton, Matthew; Martin, David

    2012-01-01

    Background. Secondary hyperparathyroidism (sHPT) represents an adaptive response to progressively impaired control of calcium, phosphorus and vitamin D in chronic kidney disease (CKD). It is characterized by parathyroid hyperplasia and excessive synthesis and secretion of parathyroid hormone (PTH). Parathyroid hyperplasia in uremic rats can be prevented by calcium-sensing receptor (CaSR) activation with the calcimimetic cinacalcet (Sensipar®/Mimpara®); however, it is unknown, how long the effects of cinacalcet persist after withdrawal of treatment or if cinacalcet is efficacious in uremic rats with established sHPT. Methods. We sought to determine the effect of cinacalcet discontinuation in uremic rats and whether cinacalcet was capable of influencing parathyroid hyperplasia in animals with established sHPT. Results. Discontinuation of cinacalcet resulted in reversal of the beneficial effects on serum PTH and parathyroid hyperplasia. In rats with established sHPT, cinacalcet decreased serum PTH and mediated regression of parathyroid hyperplasia. The cinacalcet-mediated decrease in parathyroid gland size was accompanied by increased expression of the cyclin-dependent kinase inhibitor p21. Prevention of cellular proliferation with cinacalcet occurred despite increased serum phosphorus and decreased serum calcium. Conclusions. The animal data provided suggest established parathyroid hyperplasia can be reversed by modulating CaSR activity with cinacalcet and that continued treatment may be necessary to maintain reductions in PTH. PMID:22036941

  1. New Regenerative Cycle for Vapor Compression Refrigeration

    SciTech Connect

    Mark J. Bergander

    2005-08-29

    The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient of performance for geothermal heat pumps based on a new regenerative thermodynamic cycle as comparing to existing technology. In order to demonstrate the improved performance of the prototype, it will be compared to published parameters of commercially available geothermal heat pumps manufactured by US and foreign companies. Other objectives are to optimize the design parameters and to determine the economic viability of the new technology. Background (as stated in the proposal): The proposed technology closely relates to EERE mission by improving energy efficiency, bringing clean, reliable and affordable heating and cooling to the residential and commercial buildings and reducing greenhouse gases emission. It can provide the same amount of heating and cooling with considerably less use of electrical energy and consequently has a potential of reducing our nations dependence on foreign oil. The theoretical basis for the proposed thermodynamic cycle was previously developed and was originally called a dynamic equilibrium method. This theory considers the dynamic equations of state of the working fluid and proposes the methods for modification of T-S trajectories of adiabatic transformation by changing dynamic properties of gas, such as flow rate, speed and acceleration. The substance of this proposal is a thermodynamic cycle characterized by the regenerative use of the potential energy of two-phase flow expansion, which in traditional systems is lost in expansion valves. The essential new features of the process are: (1) The application of two-step throttling of the working fluid and two-step compression of its vapor phase. (2) Use of a compressor as the initial step compression and a jet device as a second step, where throttling and compression are combined. (3) Controlled ratio of a working fluid at the first and

  2. Nonclassical Congenital Adrenal Hyperplasia and Pregnancy

    PubMed Central

    Cuhaci, Neslihan; Aydın, Cevdet; Yesilyurt, Ahmet; Pınarlı, Ferda Alpaslan; Ersoy, Reyhan; Cakir, Bekir

    2015-01-01

    Objective. The most common form of congenital adrenal hyperplasia (CAH) is 21-hydroxylase (21-OH) deficiency due to mutation of the CYP21A2 gene. Patients with nonclassical CAH (NC-CAH) are usually asymptomatic at birth and typically present in late childhood, adolescence, or adulthood with symptoms of excessive androgen secretion. Subfertility is relative in NC-CAH, but the incidence of spontaneous miscarriage is higher. Here, we report a previously undiagnosed female who gave birth to a normal male child and is planning to become pregnant again. Case Report. A 32-year-old female was referred to our clinic for obesity. Her medical history revealed that she had had three pregnancies. She was planning to become pregnant again. Her laboratory results revealed that she had NC-CAH. Since her husband is the son of her aunt and she had miscarriages and intrauterin exitus in her history, their genetic analyses were performed. Conclusion. Since most patients with NC-CAH have a severe mutation, these patients may give birth to a child with the classical CAH (C-CAH) if their partner is also carrying a severe mutation. Females with NC-CAH who desire pregnancy must be aware of the risk of having an infant with C-CAH. PMID:26558116

  3. Neointimal hyperplasia associated with synthetic hemodialysis grafts

    PubMed Central

    Li, Li; Terry, Christi M.; Shiu, Yan-Ting E.; Cheung, Alfred K.

    2008-01-01

    Stenosis is a major cause of failure of hemodialysis vascular grafts and is primarily caused by neointimal hyperplasia (NH) at the anastomoses. The objective of this article is to provide a scientific review of the biology underlying this disorder and a critical review of the state-of-the-art investigational preventive strategies in order to stimulate further research in this exciting area. The histology of the NH shows myofibroblasts (that are probably derived from adventitial fibroblasts), extracellular matrices, pro-inflammatory cells including foreign-body giant cells, a variety of growth factors and cytokines, and neovasculature. The contributing factors of the pathogenesis of NH include surgical trauma, bioincompatibility of the synthetic graft, and the various mechanical stresses that result from luminal hypertension and compliance mismatch between the vessel wall and graft. These mechanical stimuli are focal in nature and may have a significant influence on the preferential localization of the NH. Novel mechanical graft designs and local drug delivery strategies show promise in animal models in preventing graft NH development. Successful prevention of graft stenosis would provide a superior alternative to the native fistula as hemodialysis vascular access. PMID:18668026

  4. Benign Prostatic Hyperplasia: from Bench to Clinic

    PubMed Central

    Cho, Hee Ju

    2012-01-01

    Benign prostatic hyperplasia (BPH) is a prevalent disease, especially in old men, and often results in lower urinary tract symptoms (LUTS). This chronic disease has important care implications and financial risks to the health care system. LUTS are caused not only by mechanical prostatic obstruction but also by the dynamic component of obstruction. The exact etiology of BPH and its consequences, benign prostatic enlargement and benign prostatic obstruction, are not identified. Various theories concerning the causes of benign prostate enlargement and LUTS, such as metabolic syndrome, inflammation, growth factors, androgen receptor, epithelial-stromal interaction, and lifestyle, are discussed. Incomplete overlap of prostatic enlargement with symptoms and obstruction encourages focus on symptoms rather than prostate enlargement and the shifting from surgery to medicine as the treatment of BPH. Several alpha antagonists, including alfuzosin, doxazosin, tamsulosin, and terazosin, have shown excellent efficacy without severe adverse effects. In addition, new alpha antagonists, silodosin and naftopidil, and phosphodiesterase 5 inhibitors are emerging as BPH treatments. In surgical treatment, laser surgery such as photoselective vaporization of the prostate and holmium laser prostatectomy have been introduced to reduce complications and are used as alternatives to transurethral resection of the prostate (TURP) and open prostatectomy. The status of TURP as the gold standard treatment of BPH is still evolving. We review several preclinical and clinical studies about the etiology of BPH and treatment options. PMID:22468207

  5. Emerging drug therapies for benign prostatic hyperplasia.

    PubMed

    Bullock, Travis L; Andriole, Gerald L

    2006-03-01

    Benign prostatic hyperplasia (BPH) is the nonmalignant enlargement of the prostate gland caused by increases in number of both epithelial and stromal cells. Clinically, BPH leads to voiding dysfunction, which is most often referred to as lower urinary tract symptoms (LUTS). Historically, the only treatments for LUTS due to BPH were watchful waiting or surgery (transurethral or open prostatectomy). However, over the last 20 years medical therapy has taken a prominent role in the management of BPH. Current medical treatments for BPH include alpha-adrenergic receptor antagonists, inhibitors of the 5-alpha reductase enzyme and various phytotherapies. These agents are generally effective and safe; however, many patients are unable to tolerate the side effects or are refractory to medical management and require surgery. In light of this, many potential new therapies for the treatment of BPH are under development. Some represent a variation of current treatments, whereas others target novel molecular pathways within the prostate. The aim of this review is to examine current pharmacotherapies as well as to highlight emerging drugs that may improve our treatment of patients with LUTS secondary to BPH.

  6. Dutasteride/tamsulosin: in benign prostatic hyperplasia.

    PubMed

    Keating, Gillian M

    2012-05-01

    The 5α-reductase inhibitor dutasteride and the α(1)-adrenergic receptor antagonist tamsulosin are available as a fixed-dose combination for use in men with symptomatic benign prostatic hyperplasia (BPH) and an enlarged prostate. Dutasteride 0.5 mg/day plus tamsulosin 0.4 mg/day improved lower urinary tract symptoms (LUTS) to a significantly greater extent than dutasteride or tamsulosin alone in men with BPH, moderate to severe LUTS and an increased risk of disease progression, according to the results of the randomized, double-blind, multinational CombAT trial. The mean change from baseline in the total International Prostate Symptom Score was significantly greater with dutasteride plus tamsulosin than with dutasteride or tamsulosin alone after 2 years (primary endpoint) and 4 years of therapy. After 4 years' therapy in the CombAT trial, the time to first acute urinary retention or BPH-related surgery (primary endpoint) significantly favoured men with symptomatic BPH who were receiving dutasteride plus tamsulosin versus those receiving tamsulosin alone, with no significant difference between recipients of dutasteride plus tamsulosin and recipients of dutasteride alone. In the CombAT trial, health-related quality of life and treatment satisfaction were improved to a significantly greater extent with dutasteride plus tamsulosin than with dutasteride or tamsulosin alone. Combination therapy with oral dutasteride plus tamsulosin was generally well tolerated in patients with symptomatic BPH in the CombAT trial.

  7. [Regenerative medicine in head and neck reconstructive surgery].

    PubMed

    Riedel, F; Goessler, U R; Stern-Straeter, J; Riedel, K; Hörmann, K

    2008-03-01

    Autologous transplantation is regarded as the gold standard in the treatment of congenital or acquired deformities. However, the availability of autologous tissue for transplantation is often limited. Regenerative medicine aims to activate individuals' own intrinsic regenerative mechanisms and embraces tissue engineering, cell/system biology, gene therapy and stem-cell biology. Most approaches in tissue engineering are based on the expansion of small autologous cell aggregates. Tissue engineering supplemented by isolated and amplified stem cells is another very promising option for producing autologous transplants and getting over the limited availability. The association of stem cell-based tissue engineering and gene therapy allows the creation of regenerative tissue in the optimal ambience of regulatory proteins. This leads to great opportunities in the transplantation of skin, bones or cartilage. This paper presents the current status and the possible benefits, but also the limitations, of regenerative medicine in reconstructive surgery of the head and neck.

  8. Science and Ethics: Bridge to the Future for Regenerative Medicine

    PubMed Central

    Patricio, Ventura-Juncá

    2011-01-01

    The objective of this article is to reflect on the relationship between regenerative medicine and ethics, using as references the Aristotelian concept of what is ethical and that of Raessler Van Potter about bioethics. To do this, I will briefly describe the advances in regenerative medicine with stem cells, the strategies for producing pluripotential cells without destroying human embryos, and the great potential of stem cells to improve life for Humanity, noting that for this to be possible, it is necessary to locate the role of regenerative medicine in the context of human values and well being. In this way, this article has a real perspective of the role that regenerative medicine can play in benefitting human beings and engendering respect for human and natural environments. PMID:24298338

  9. Iron serves as diffusion barrier in thermally regenerative galvanic cell

    NASA Technical Reports Server (NTRS)

    Crouthamel, C. E.

    1967-01-01

    Pure iron or iron-coated diaphragm provides a hydrogen diffusion electrode for a thermally regenerative galvanic cell. It allows the gas to diffuse through its interatomic spaces and resists the corrosive action of the cell environment.

  10. 3. INSIDE BATCH FURNACE BUILDING, VIEW LOOKING NORTH AT REGENERATIVE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. INSIDE BATCH FURNACE BUILDING, VIEW LOOKING NORTH AT REGENERATIVE BATCH FURNACES ON LEFT AND 5 TON CAPACITY CHARGING MACHINE ON RIGHT. - U.S. Steel Duquesne Works, 22-Inch Bar Mill, Along Monongahela River, Duquesne, Allegheny County, PA

  11. Advancing pig cloning technologies towards application in regenerative medicine.

    PubMed

    Nagashima, H; Matsunari, H; Nakano, K; Watanabe, M; Umeyama, K; Nagaya, M

    2012-08-01

    Regenerative medicine is expected to make a significant contribution by development of novel therapeutic treatments for intractable diseases and for improving the quality of life of patients. Many advances in regenerative medicine, including basic and translational research, have been developed and tested in experimental animals; pigs have played an important role in various aspects of this work. The value of pigs as a model species is being enhanced by the generation of specially designed animals through cloning and genetic modifications, enabling more sophisticated research to be performed and thus accelerating the clinical application of regenerative medicine. This article reviews the significant aspects of the creation and application of cloned and genetically modified pigs in regenerative medicine research and considers the possible future directions of the technology. We also discuss the importance of reproductive biology as an interface between basic science and clinical medicine.

  12. Cell sheet engineering for regenerative medicine: current challenges and strategies.

    PubMed

    Owaki, Toshiyuki; Shimizu, Tatsuya; Yamato, Masayuki; Okano, Teruo

    2014-07-01

    Substantial progress made in the areas of stem cell research and regenerative medicine has provided a number of innovative methods to repair or regenerate defective tissues and organs. Although previous studies regarding regenerative medicine, especially those involving induced pluripotent stem cells, have been actively promoted in the past decade, there remain some challenges that need to be addressed in order to enable clinical applications. Designed for use in clinical applications, cell sheet engineering has been developed as a unique, scaffold-free method of cell processing utilizing temperature-responsive cell culture vessels. Clinical studies using cell sheets have shown positive outcomes and will be translated into clinical practice in the near future. However, several challenges stand in the way of the industrialization of cell sheet products and the widespread acceptance of regenerative medicine based on cell sheet engineering. This review describes current strategies geared towards the realization of the regenerative medicine approach.

  13. From regenerative dentistry to regenerative medicine: progress, challenges, and potential applications of oral stem cells.

    PubMed

    Xiao, Li; Nasu, Masanori

    2014-01-01

    Adult mesenchymal stem cells (MSCs) and epithelial stem cells play essential roles in tissue repair and self-healing. Oral MSCs and epithelial stem cells can be isolated from adult human oral tissues, for example, teeth, periodontal ligament, and gingiva. Cocultivated adult oral epithelial stem cells and MSCs could represent some developmental events, such as epithelial invagination and tubular structure formation, signifying their potentials for tissue regeneration. Oral epithelial stem cells have been used in regenerative medicine over 1 decade. They are able to form a stratified cell sheet under three-dimensional culture conditions. Both experimental and clinical data indicate that the cell sheets can not only safely and effectively reconstruct the damaged cornea in humans, but also repair esophageal ulcer in animal models. Oral MSCs include dental pulp stem cells (DPSCs), stem cells from exfoliated deciduous teeth (SHED), stem cells from apical papilla (SCAP), periodontal ligament stem cells (PDLSCs), and mesenchymal stem cells from gingiva (GMSCs). They are widely applied in both regenerative dentistry and medicine. DPSCs, SHED, and SCAP are able to form dentin-pulp complex when being transplanted into immunodeficient animals. They have been experimentally used for the regeneration of dental pulp, neuron, bone muscle and blood vessels in animal models and have shown promising results. PDLSCs and GMSCs are demonstrated to be ideal cell sources for repairing the damaged tissues of periodontal, muscle, and tendon. Despite the abovementioned applications of oral stem cells, only a few human clinical trials are now underway to use them for the treatment of certain diseases. Since clinical use is the end goal, their true regenerative power and safety need to be further examined.

  14. Citrate-Based Biomaterials and Their Applications in Regenerative Engineering

    NASA Astrophysics Data System (ADS)

    Tran, Richard T.; Yang, Jian; Ameer, Guillermo A.

    2015-07-01

    Advances in biomaterials science and engineering are crucial to translating regenerative engineering, an emerging field that aims to recreate complex tissues, into clinical practice. In this regard, citrate-based biomaterials have become an important tool owing to their versatile material and biological characteristics including unique antioxidant, antimicrobial, adhesive, and fluorescent properties. This review discusses fundamental design considerations, strategies to incorporate unique functionality, and examples of how citrate-based biomaterials can be an enabling technology for regenerative engineering.

  15. Citrate-Based Biomaterials and Their Applications in Regenerative Engineering

    PubMed Central

    Tran, Richard T.; Yang, Jian; Ameer, Guillermo A.

    2015-01-01

    Advances in biomaterials science and engineering are crucial to translating regenerative engineering, an emerging field that aims to recreate complex tissues, into clinical practice. In this regard, citrate-based biomaterials have become an important tool owing to their versatile material and biological characteristics including unique antioxidant, antimicrobial, adhesive, and fluorescent properties. This review discusses fundamental design considerations, strategies to incorporate unique functionality, and examples of how citrate-based biomaterials can be an enabling technology for regenerative engineering. PMID:27004046

  16. Adipose stem cells: biology, safety, regulation, and regenerative potential.

    PubMed

    Minteer, Danielle M; Marra, Kacey G; Rubin, J Peter

    2015-04-01

    This article discusses adipose-derived stem cell (ASC) biology, describes the current knowledge in the literature for the safety and regulation of ASCs, and provides a brief overview of the regenerative potential of ASCs. It is not an exhaustive listing of all available clinical studies or every study applying ASCs in tissue engineering and regenerative medicine, but is an objective commentary of these topics.

  17. Regenerative life support system research and concepts

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Life support systems that involve recycling of atmospheres, water, food and waste are so complex that models incorporating all the interactions and relationships are vital to design, development, simulations, and ultimately to control of space qualified systems. During early modeling studies, FORTRAN and BASIC programs were used to obtain numerical comparisons of the performance of different regenerative concepts. Recently, models were made by combining existing capabilities with expert systems to establish an Intelligent Design Support Environment for simpliflying user interfaces and to address the need for the engineering aspects. Progress was also made toward modeling and evaluating the operational aspects of closed loop life support systems using Time-step and Dynamic simulations over a period of time. Example models are presented which show the status and potential of developed modeling techniques. For instance, closed loop systems involving algae systeMs for atmospheric purification and food supply augmentation, plus models employing high plants and solid waste electrolysis are described and results of initial evaluations are presented.

  18. PLURIPOTENT STEM CELL APPLICATIONS FOR REGENERATIVE MEDICINE

    PubMed Central

    Angelos, Mathew G.; Kaufman, Dan S.

    2015-01-01

    Purpose of Review In this review, we summarize the current status of clinical trials using therapeutic cells produced from human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs). We also discuss combined cell and gene therapy via correction of defined mutations in human pluripotent stem cells and provide commentary on key obstacles facing wide-scale clinical adoption of pluripotent stem cell-based therapy. Recent Findings Initial data suggest hESC/hiPSC-derived cell products used for retinal repair and spinal cord injury are safe for human use. Early stage studies for treatment of cardiac injury and diabetes are also in progress. However, there remain key concerns regarding the safety and efficacy of these cells that need to be addressed in additional well-designed clinical trials. Advances using the CRISPR/Cas9 gene-editing system offer an improved tool for more rapid and on-target gene correction of genetic diseases. Combined gene and cell therapy using human pluripotent stem cells may provide an additional curative approach for disabling or lethal genetic and degenerative diseases where there are currently limited therapeutic opportunities. Summary Human pluripotent stem cells are emerging as a promising tool to produce cells and tissues suitable for regenerative therapy for a variety of genetic and degenerative diseases. PMID:26536430

  19. High power, high beam quality regenerative amplifier

    DOEpatents

    Hackel, Lloyd A.; Dane, Clifford B.

    1993-01-01

    A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

  20. High power, high beam quality regenerative amplifier

    DOEpatents

    Hackel, L.A.; Dane, C.B.

    1993-08-24

    A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

  1. Unitized Regenerative Fuel Cell System Development

    NASA Technical Reports Server (NTRS)

    Burke, Kenneth A.

    2003-01-01

    Unitized Regenerative Fuel Cells (URFC) have recently been developed by several fuel cell manufacturers. These manufacturers have concentrated their efforts on the development of the cell stack technology itself, and have not up to this point devoted much effort to the design and development of the balance of plant. A fuel cell technology program at the Glenn Research Center (GRC) that has as its goal the definition and feasibility testing of the URFC system balance of plant. Besides testing the feasibility, the program also intends to minimize the system weight, volume, and parasitic power as its goal. The design concept currently being developed uses no pumps to circulate coolant or reactants, and minimizes the ancillary components to only the oxygen and hydrogen gas storage tanks, a water storage tank, a loop heat pipe to control the temperature and two pressure control devices to control the cell stack pressures during operation. The information contained in this paper describes the design and operational concepts employed in this concept. The paper also describes the NASA Glenn research program to develop this concept and test its feasibility.

  2. Introduction to stem cells and regenerative medicine.

    PubMed

    Kolios, George; Moodley, Yuben

    2013-01-01

    Stem cells are a population of undifferentiated cells characterized by the ability to extensively proliferate (self-renewal), usually arise from a single cell (clonal), and differentiate into different types of cells and tissue (potent). There are several sources of stem cells with varying potencies. Pluripotent cells are embryonic stem cells derived from the inner cell mass of the embryo and induced pluripotent cells are formed following reprogramming of somatic cells. Pluripotent cells can differentiate into tissue from all 3 germ layers (endoderm, mesoderm, and ectoderm). Multipotent stem cells may differentiate into tissue derived from a single germ layer such as mesenchymal stem cells which form adipose tissue, bone, and cartilage. Tissue-resident stem cells are oligopotent since they can form terminally differentiated cells of a specific tissue. Stem cells can be used in cellular therapy to replace damaged cells or to regenerate organs. In addition, stem cells have expanded our understanding of development as well as the pathogenesis of disease. Disease-specific cell lines can also be propagated and used in drug development. Despite the significant advances in stem cell biology, issues such as ethical controversies with embryonic stem cells, tumor formation, and rejection limit their utility. However, many of these limitations are being bypassed and this could lead to major advances in the management of disease. This review is an introduction to the world of stem cells and discusses their definition, origin, and classification, as well as applications of these cells in regenerative medicine.

  3. Mesenchymal dental stem cells in regenerative dentistry.

    PubMed

    Rodríguez-Lozano, Francisco-Javier; Insausti, Carmen-Luisa; Iniesta, Francisca; Blanquer, Miguel; Ramírez, María-del-Carmen; Meseguer, Luis; Meseguer-Henarejos, Ana-Belén; Marín, Noemí; Martínez, Salvador; Moraleda, José-María

    2012-11-01

    In the last decade, tissue engineering is a field that has been suffering an enormous expansion in the regenerative medicine and dentistry. The use of cells as mesenchymal dental stem cells of easy access for dentist and oral surgeon, immunosuppressive properties, high proliferation and capacity to differentiate into odontoblasts, cementoblasts, osteoblasts and other cells implicated in the teeth, suppose a good perspective of future in the clinical dentistry. However, is necessary advance in the known of growth factors and signalling molecules implicated in tooth development and regeneration of different structures of teeth. Furthermore, these cells need a fabulous scaffold that facility their integration, differentiation, matrix synthesis and promote multiple specific interactions between cells. In this review, we give a brief description of tooth development and anatomy, definition and classification of stem cells, with special attention of mesenchymal stem cells, commonly used in the cellular therapy for their trasdifferentiation ability, non ethical problems and acceptable results in preliminary clinical trials. In terms of tissue engineering, we provide an overview of different types of mesenchymal stem cells that have been isolated from teeth, including dental pulp stem cells (DPSCs), stem cells from human exfoliated deciduous teeth (SHEDs), periodontal ligament stem cells (PDLSCs), dental follicle progenitor stem cells (DFPCs), and stem cells from apical papilla (SCAPs), growth factors implicated in regeneration teeth and types of scaffolds for dental tissue regeneration.

  4. How predictable are periodontal regenerative procedures?

    PubMed

    Zohar, Ron; Tenenbaum, Howard C

    2005-10-01

    Periodontal regeneration has become one of the primary objectives of periodontal therapy. The resulting scientific endeavours have elucidated modes of periodontal wound healing, the growth of periodontal cells and their association with the surrounding matrix, and growth-promoting factors. The periodontal regeneration industry is producing better and more expensive devices, but the criteria for evaluating their success have not progressed to the same extent. Although clinical measurements of attachment level and probing depths, along with radiography, are good methods of evaluating tooth survival and prognosis, they do not indicate true biological regeneration. In addition, the regeneration industry may encourage the overuse of allografts and alloplasts which may serve as an impediment to simple wound healing. This review is a critical assessment of the clinical use of various regenerative tools, specifically bone replacements and membranes. The future of the regeneration industry may depend on the merging of various technologies and biological concepts, including the possible use of biological barriers, various bone and periodontal growth inducers, and artificial matrices that will attract or carry the cells necessary for regeneration.

  5. Bioactive nanofibrous scaffolds for regenerative endodontics.

    PubMed

    Bottino, M C; Kamocki, K; Yassen, G H; Platt, J A; Vail, M M; Ehrlich, Y; Spolnik, K J; Gregory, R L

    2013-11-01

    Here we report the synthesis, materials characterization, antimicrobial capacity, and cytocompatibility of novel antibiotic-containing scaffolds. Metronidazole (MET) or Ciprofloxacin/(CIP) was mixed with a polydioxanone (PDS)polymer solution at 5 and 25 wt% and processed into fibers. PDS fibers served as a control. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), tensile testing, and high-performance liquid chromatography (HPLC) were used to assess fiber morphology, chemical structure, mechanical properties, and drug release, respectively. Antimicrobial properties were evaluated against those of Porphyromonas gingivalis/Pg and Enterococcus faecalis/Ef. Cytotoxicity was assessed in human dental pulp stem cells (hDPSCs). Statistics were performed, and significance was set at the 5% level. SEM imaging revealed a submicron fiber diameter. FTIR confirmed antibiotic incorporation. The tensile values of hydrated 25 wt% CIP scaffold were significantly lower than those of all other groups. Analysis of HPLC data confirmed gradual, sustained drug release from the scaffolds over 48 hrs. CIP-containing scaffolds significantly (p < .00001) inhibited biofilm growth of both bacteria. Conversely, MET-containing scaffolds inhibited only Pg growth. Agar diffusion confirmed the antimicrobial properties against specific bacteria for the antibiotic-containing scaffolds. Only the 25 wt% CIP-containing scaffolds were cytotoxic. Collectively, this study suggests that polymer-based antibiotic-containing electrospun scaffolds could function as a biologically safe antimicrobial drug delivery system for regenerative endodontics.

  6. Regenerative Capacity of Macrophages for Remyelination

    PubMed Central

    Rawji, Khalil S.; Mishra, Manoj K.; Yong, V. Wee

    2016-01-01

    White matter injury, consisting of loss of axons, myelin, and oligodendrocytes, is common in many neurological disorders and is believed to underlie several motor and sensory deficits. Remyelination is the process in which the insulative myelin sheath is restored to axons, thereby facilitating recovery from functional loss. Remyelination proceeds with oligodendrocyte precursor cells (OPCs) that differentiate into oligodendrocytes to synthesize the new myelin sheath after demyelination. This process is influenced by several factors, including trophic factors, inhibitory molecules in the lesion microenvironment, age of the subject, as well as the inflammatory response. Currently studied strategies that enhance remyelination consist of pharmacological approaches that directly induce OPC differentiation or using agents to neutralize the inhibitory microenvironment. Another strategy is to harness a reparative inflammatory response. This response, coordinated by central nervous system resident microglia and peripherally-derived infiltrating macrophages, has been shown to be important in the remyelination process. These innate immune cells perform important functions in remyelination, including the proteolysis and phagocytosis of inhibitory molecules present in the lesion microenvironment, the provision of trophic and metabolic factors to OPCs, in addition to iron handling capacity. Additionally, an initial pro-inflammatory phase followed by a regulatory/anti-inflammatory phase has been shown to be important for OPC proliferation and differentiation, respectively. This review will discuss the beneficial roles of macrophages/microglia in remyelination and discuss therapeutic strategies to obtain the optimal regenerative macrophage phenotype for enhanced remyelination. PMID:27243011

  7. Recent advances in acellular regenerative tissue scaffolds.

    PubMed

    Protzman, Nicole M; Brigido, Stephen A

    2015-01-01

    The management of chronic wounds is a considerable challenge for foot and ankle surgeons. The well-established tenets of adequate vascular supply, debridement with eradication of infection, and offloading must be employed in the management of all extremity wounds. Regenerative scaffolds are a viable means of reestablishing a favorable wound environment. The matrix facilitates cell migration, chemoattraction, angiogenesis, wound bed granulation, and expedited wound closure. Although studies have demonstrated success with acellular matrices, a multimodal approach should always be employed to improve healing success. Negative pressure wound therapy, compression, offloading, and antibiotics are advocated to improve outcomes. Acellular graft selection requires a multifactorial analysis, taking into consideration the specific patient and wound characteristics as well as the differences between acellular matrices. Patient age, comorbidities, activity level, and ability to comply with protocol as well as wound etiology, duration, depth, surface area, exudate, bacterial burden, location, vascular status, ischemic status, and presentation are all critical components. To effectively choose a matrix, the clinician must have a comprehensive understanding of the products available and the data validating their use. The mechanisms by which the acellular matrix accelerates wound healing and increases the likelihood of wound healing continue to be investigated. However, it is clear that these acellular biologic tissue scaffolds are incorporating into the host tissue, with resultant revascularization and cellular repopulation. Moving forward, additional investigations examining the effectiveness of acellular biologic tissue scaffolds to improve healing in complex, nondiabetic wounds are warranted.

  8. Liver-Regenerative Transplantation: Regrow and Reset

    PubMed Central

    de l’Hortet, A. Collin; Takeishi, K.; Guzman-Lepe, J.; Handa, K.; Matsubara, K.; Fukumitsu, K.; Dorko, K.; Presnell, S. C.; Yagi, H.; Soto-Gutierrez, A.

    2016-01-01

    Liver transplantation, either a partial liver from a living or deceased donor or a whole liver from a deceased donor, is the only curative therapy for severe end-stage liver disease. Only one-third of those on the liver transplant waiting list will be transplanted, and the demand for livers is projected to increase 23% in the next 20 years. Consequently, organ availability is an absolute constraint on the number of liver transplants that can be performed. Regenerative therapies aim to enhance liver tissue repair and regeneration by any means available (cell repopulation, tissue engineering, biomaterials, proteins, small molecules, and genes). Recent experimental work suggests that liver repopulation and engineered liver tissue are best suited to the task if an unlimited availability of functional induced pluripotent stem (iPS)–derived liver cells can be achieved. The derivation of iPS cells by reprogramming cell fate has opened up new lines of investigation, for instance, the generation of iPS-derived xenogeneic organs or the possibility of simply inducing the liver to reprogram its own hepatocyte function after injury. We reviewed current knowledge about liver repopulation, generation of engineered livers and reprogramming of liver function. We also discussed the numerous barriers that have to be overcome for clinical implementation. PMID:26699680

  9. New biomimetic directions in regenerative ophthalmology.

    PubMed

    Green, David W; Watson, Gregory S; Watson, Jolanta; Abraham, Samuel J K

    2012-03-01

    One of the most complete and permanent ways of treating many causes of visual impairment and blindness is to replace the entire affected tissue with pre-cultured ocular tissues supported and maintained on biomaterial frameworks. One direction towards enhancing ocular tissue regeneration on biomaterials, in the laboratory is by applying biomimicry. Specifically to engineer biomaterials with important functional elements of the native extracellular matrices, such as topography, that support and organise cells into coherent tissues. Further problems in regenerative ophthalmology can be potentially solved through application of biomimicry. They include, more efficient ways of moving and transplanting cultivated tissues into correct therapeutic locations inside the eye and scar-less, non-destructive healing of surgical incisions and wounds, to repair structural integrity of tissues at the ocular surface. Two examples are given to show this potential for redeveloping an ocular epithelium onto a nanostructured insect wing surface and producing an origami membrane modelled on deployable structures in nature. Efforts to harness natural innovation will eventually provide unique designs and structures that cannot for now be made synthetically, for regeneration of clinically acceptable ocular tissues.

  10. Cold end fouling regenerative air preheaters

    SciTech Connect

    Levy, E.; D`Agostini, M.; Sarunac, N.; Yilmaz, A.

    1996-05-01

    Condensation of sulfuric acid occurs in the cold end flow passages of a regenerative air preheater (APH) when local metal temperatures fall beneath the acid dew point of the flue gas. In coal-fired units, the acid condensate acts as an adhesive for fly ash particulate, the deposition of which gradually reduces the cross-sectional area of the passage, leading to higher gas pressure drops and increased fan power requirements. In units which are fan-limited, costly unit derates and forced outages for APH cleaning often occur. Although optimization of APH operation is a highly unit specific issue, the method of approaching the problem is fairly general and can involve combinations of theoretical analysis, field measurements and proper data regression. This paper describes case studies of the APH acid condensation and fouling characteristics at three different coal-fired utility boilers, which illustrate specific applications of the general optimization technique. The approach is also valid for units which employ ammonia injection.

  11. Regenerative medicine as applied to general surgery.

    PubMed

    Orlando, Giuseppe; Wood, Kathryn J; De Coppi, Paolo; Baptista, Pedro M; Binder, Kyle W; Bitar, Khalil N; Breuer, Christopher; Burnett, Luke; Christ, George; Farney, Alan; Figliuzzi, Marina; Holmes, James H; Koch, Kenneth; Macchiarini, Paolo; Mirmalek Sani, Sayed-Hadi; Opara, Emmanuel; Remuzzi, Andrea; Rogers, Jeffrey; Saul, Justin M; Seliktar, Dror; Shapira-Schweitzer, Keren; Smith, Tom; Solomon, Daniel; Van Dyke, Mark; Yoo, James J; Zhang, Yuanyuan; Atala, Anthony; Stratta, Robert J; Soker, Shay

    2012-05-01

    The present review illustrates the state of the art of regenerative medicine (RM) as applied to surgical diseases and demonstrates that this field has the potential to address some of the unmet needs in surgery. RM is a multidisciplinary field whose purpose is to regenerate in vivo or ex vivo human cells, tissues, or organs to restore or establish normal function through exploitation of the potential to regenerate, which is intrinsic to human cells, tissues, and organs. RM uses cells and/or specially designed biomaterials to reach its goals and RM-based therapies are already in use in several clinical trials in most fields of surgery. The main challenges for investigators are threefold: Creation of an appropriate microenvironment ex vivo that is able to sustain cell physiology and function in order to generate the desired cells or body parts; identification and appropriate manipulation of cells that have the potential to generate parenchymal, stromal and vascular components on demand, both in vivo and ex vivo; and production of smart materials that are able to drive cell fate.

  12. REGENERATIVE MEDICINE AS APPLIED TO GENERAL SURGERY

    PubMed Central

    Orlando, Giuseppe; Wood, Kathryn J; De Coppi, Paolo; Baptista, Pedro M; Binder, Kyle W; Bitar, Khalil N; Breuer, Christopher; Burnett, Luke; Christ, George; Farney, Alan; Figliuzzi, Marina; Holmes, James H; Koch, Kenneth; Macchiarini, Paolo; Sani, Sayed-Hadi Mirmalek; Opara, Emmanuel; Remuzzi, Andrea; Rogers, Jeffrey; Saul, Justin M; Seliktar, Dror; Shapira-Schweitzer, Keren; Smith, Tom; Solomon, Daniel; Van Dyke, Mark; Yoo, James J; Zhang, Yuanyuan; Atala, Anthony; Stratta, Robert J; Soker, Shay

    2012-01-01

    The present review illustrates the state of the art of regenerative medicine (RM) as applied to surgical diseases and demonstrates that this field has the potential to address some of the unmet needs in surgery. RM is a multidisciplinary field whose purpose is to regenerate in vivo or ex vivo human cells, tissues or organs in order to restore or establish normal function through exploitation of the potential to regenerate, which is intrinsic to human cells, tissues and organs. RM uses cells and/or specially designed biomaterials to reach its goals and RM-based therapies are already in use in several clinical trials in most fields of surgery. The main challenges for investigators are threefold: Creation of an appropriate microenvironment ex vivo that is able to sustain cell physiology and function in order to generate the desired cells or body parts; identification and appropriate manipulation of cells that have the potential to generate parenchymal, stromal and vascular components on demand, both in vivo and ex vivo; and production of smart materials that are able to drive cell fate. PMID:22330032

  13. Manufacturing Road Map for Tissue Engineering and Regenerative Medicine Technologies

    PubMed Central

    Hunsberger, Joshua; Harrysson, Ola; Shirwaiker, Rohan; Starly, Binil; Wysk, Richard; Cohen, Paul; Allickson, Julie; Yoo, James

    2015-01-01

    Summary The Regenerative Medicine Foundation Annual Conference held on May 6 and 7, 2014, had a vision of assisting with translating tissue engineering and regenerative medicine (TERM)-based technologies closer to the clinic. This vision was achieved by assembling leaders in the field to cover critical areas. Some of these critical areas included regulatory pathways for regenerative medicine therapies, strategic partnerships, coordination of resources, developing standards for the field, government support, priorities for industry, biobanking, and new technologies. The final day of this conference featured focused sessions on manufacturing, during which expert speakers were invited from industry, government, and academia. The speakers identified and accessed roadblocks plaguing the field where improvements in advanced manufacturing offered many solutions. The manufacturing sessions included (a) product development toward commercialization in regenerative medicine, (b) process challenges to scale up manufacturing in regenerative medicine, and (c) infrastructure needs for manufacturing in regenerative medicine. Subsequent to this, industry was invited to participate in a survey to further elucidate the challenges to translation and scale-up. This perspective article will cover the lessons learned from these manufacturing sessions and early results from the survey. We also outline a road map for developing the manufacturing infrastructure, resources, standards, capabilities, education, training, and workforce development to realize the promise of TERM. PMID:25575525

  14. Manufacturing road map for tissue engineering and regenerative medicine technologies.

    PubMed

    Hunsberger, Joshua; Harrysson, Ola; Shirwaiker, Rohan; Starly, Binil; Wysk, Richard; Cohen, Paul; Allickson, Julie; Yoo, James; Atala, Anthony

    2015-02-01

    The Regenerative Medicine Foundation Annual Conference held on May 6 and 7, 2014, had a vision of assisting with translating tissue engineering and regenerative medicine (TERM)-based technologies closer to the clinic. This vision was achieved by assembling leaders in the field to cover critical areas. Some of these critical areas included regulatory pathways for regenerative medicine therapies, strategic partnerships, coordination of resources, developing standards for the field, government support, priorities for industry, biobanking, and new technologies. The final day of this conference featured focused sessions on manufacturing, during which expert speakers were invited from industry, government, and academia. The speakers identified and accessed roadblocks plaguing the field where improvements in advanced manufacturing offered many solutions. The manufacturing sessions included (a) product development toward commercialization in regenerative medicine, (b) process challenges to scale up manufacturing in regenerative medicine, and (c) infrastructure needs for manufacturing in regenerative medicine. Subsequent to this, industry was invited to participate in a survey to further elucidate the challenges to translation and scale-up. This perspective article will cover the lessons learned from these manufacturing sessions and early results from the survey. We also outline a road map for developing the manufacturing infrastructure, resources, standards, capabilities, education, training, and workforce development to realize the promise of TERM.

  15. Current Laser Treatments for Benign Prostatic Hyperplasia

    PubMed Central

    Son, Hwancheol; Song, Sang Hoon

    2010-01-01

    The latest technical improvements in the surgical armamentarium are remarkable. In particular, advancements in the urologic field are so exceptional that we could observe the flare-up of robot-assisted laparoscopic radical prostatectomy for prostate cancer and laser prostatectomy for benign prostatic hyperplasia (BPH). Photoselective vaporization of the prostate (PVP) and holmium laser prostatectomy are the most generalized options for laser surgery of BPH, and both modalities have shown good postoperative results. In comparison to transurethral prostatectomy (TURP), they showed similar efficacy and a much lower complication rate in randomized prospective clinical trials. Even in cases of large prostates, laser prostatectomy showed comparable efficacy and safety profiles compared to open prostatectomy. From a technical point of view, PVP is considered to be an easier technique for the urologist to master. Furthermore, patients can be safely followed up in an outpatient clinic. Holmium laser enucleation of the prostate (HoLEP) mimics open prostatectomy because the adenomatous tissue is peeled off the surgical capsule in both procedures. Therefore, HoLEP shows notable volume reduction of the prostate similar to open prostatectomy with fewer blood transfusions, shorter hospital stay, and cost reduction regardless of prostate size. Outcomes of laser prostatectomy for BPH are encouraging but sometimes are unbalanced because safety and feasibility studies were reported mainly for PVP, whereas long-term data are mostly available for HoLEP. We need longer-term randomized clinical data to identify the reoperation rate of PVP and to determine which procedure is the ideal alternative to TURP and open prostatectomy for each patient. PMID:21165192

  16. Platelet derivatives in regenerative medicine: an update.

    PubMed

    De Pascale, Maria Rosaria; Sommese, Linda; Casamassimi, Amelia; Napoli, Claudio

    2015-01-01

    Prior preclinical and clinical studies support the use of platelet-derived products for the treatment of soft and hard tissue lesions. These regenerative effects are controlled by autocrine and paracrine biomolecules including growth factors and cytokines contained in platelet alpha granules. Each growth factor is involved in a phase of the healing process, such as inflammation, collagen synthesis, tissue granulation, and angiogenesis collectively promoting tissue restitution. Platelet derivatives have been prepared as platelet-rich plasma, platelet gel, platelet-rich fibrin, and platelet eye drops. These products vary in their structure, growth factors, composition, and cytokine concentrations. Here, we review the current use of platelet-derived biological products focusing on the rationale for their use and the main requirements for their preparation. Variation in the apparent therapeutic efficacy may have resulted from a lack of reproducible, standardized protocols for preparation. Despite several individual studies showing favorable treatment effects, some randomized controlled trials as well as meta-analyses have found no constant clinical benefit from the application of platelet-derived products for prevention of tissue lesions. Recently, 3 published studies in dentistry showed an improvement in bone density. Seven published studies showed positive results in joint regeneration. Five published studies demonstrated an improvement in the wound healing, and an improvement of eye epithelial healing was observed in 2 reports. Currently, at least 14 ongoing clinical trials in phase 3 or 4 have been designed with large groups of treated patients (n > 100). Because the rationale of the therapy with platelet-derived compounds is still debated, a definitive insight can be acquired only when these large randomized trials will be completed.

  17. Clinical cardiac regenerative studies in children

    PubMed Central

    Pavo, Imre J; Michel-Behnke, Ina

    2017-01-01

    Although the incidence of pediatric heart failure is low, the mortality is relatively high, with severe clinical symptoms requiring repeated hospitalization or intensive care treatment in the surviving patients. Cardiac biopsy specimens have revealed a higher number of resident human cardiac progenitor cells, with greater proliferation and differentiation capacity, in the neonatal period as compared with adults, demonstrating the regeneration potential of the young heart, with rising interest in cardiac regeneration therapy in critically ill pediatric patients. We review here the available literature data, searching the MEDLINE, Google Scholar and EMBASE database for completed, and www.clinicaltrials.gov homepage for ongoing studies involving pediatric cardiac regeneration reports. Because of difficulties conducting randomized blinded clinical trials in pediatric patients, mostly case reports or cohort studies with a limited number of individuals have been published in the field of pediatric regenerative cardiology. The majority of pediatric autologous cell transplantations into the cardiac tissue have been performed in critically ill children with severe or terminal heart failure. Congenital heart disease, myocarditis, and idiopathic hypertrophic or dilated cardiomyopathy leading to congestive heart failure are some possible areas of interest for pediatric cardiac regeneration therapy. Autologous bone marrow mononuclear cells, progenitor cells, or cardiospheres have been applied either intracoronary or percutaneously intramyocardially in severely ill children, leading to a reported clinical benefit of cell-based cardiac therapies. In conclusion, compassionate use of autologous stem cell administration has led to at least short-term improvement in heart function and clinical stability in the majority of the critically ill pediatric patients. PMID:28289528

  18. Clinical cardiac regenerative studies in children.

    PubMed

    Pavo, Imre J; Michel-Behnke, Ina

    2017-02-26

    Although the incidence of pediatric heart failure is low, the mortality is relatively high, with severe clinical symptoms requiring repeated hospitalization or intensive care treatment in the surviving patients. Cardiac biopsy specimens have revealed a higher number of resident human cardiac progenitor cells, with greater proliferation and differentiation capacity, in the neonatal period as compared with adults, demonstrating the regeneration potential of the young heart, with rising interest in cardiac regeneration therapy in critically ill pediatric patients. We review here the available literature data, searching the MEDLINE, Google Scholar and EMBASE database for completed, and www.clinicaltrials.gov homepage for ongoing studies involving pediatric cardiac regeneration reports. Because of difficulties conducting randomized blinded clinical trials in pediatric patients, mostly case reports or cohort studies with a limited number of individuals have been published in the field of pediatric regenerative cardiology. The majority of pediatric autologous cell transplantations into the cardiac tissue have been performed in critically ill children with severe or terminal heart failure. Congenital heart disease, myocarditis, and idiopathic hypertrophic or dilated cardiomyopathy leading to congestive heart failure are some possible areas of interest for pediatric cardiac regeneration therapy. Autologous bone marrow mononuclear cells, progenitor cells, or cardiospheres have been applied either intracoronary or percutaneously intramyocardially in severely ill children, leading to a reported clinical benefit of cell-based cardiac therapies. In conclusion, compassionate use of autologous stem cell administration has led to at least short-term improvement in heart function and clinical stability in the majority of the critically ill pediatric patients.

  19. Plastic Surgery Challenges in War Wounded II: Regenerative Medicine

    PubMed Central

    Valerio, Ian L.; Sabino, Jennifer M.; Dearth, Christopher L.

    2016-01-01

    Background: A large volume of service members have sustained complex injuries during Operations Iraqi Freedom (OIF) and Enduring Freedom (OEF). These injuries are complicated by contamination with particulate and foreign materials, have high rates of bacterial and/or fungal infections, are often composite-type defects with massive soft tissue wounds, and usually have multisystem involvement. While traditional treatment modalities remain a mainstay for optimal wound care, traditional reconstruction approaches alone may be inadequate to fully address the scope and magnitude of such massive complex wounds. As a result of these difficult clinical problems, the use of regenerative medicine therapies, such as autologous adipose tissue grafting, stem cell therapies, nerve allografts, and dermal regenerate templates/extracellular matrix scaffolds, is increased as adjuncts to traditional reconstructive measures. Basic and Clinical Science Advances: The beneficial applications of regenerative medicine therapies have been well characterized in both in vitro studies and in vivo animal studies. The use of these regenerative medicine techniques in the treatment of combat casualty injuries has been increasing throughout the recent war conflicts. Clinical Care Relevance: Military medicine has shown positive results when utilizing certain regenerative medicine modalities in treating complex war wounds. As a result, multi-institution clinical trials are underway to further evaluate these observations and reconstruction measures. Conclusion: Successful combat casualty wound care often requires a combination of traditional aspects of the reconstructive ladder/elevator with adoption of various regenerative medicine therapies. Due to the recent OIF/OEF conflicts, a high volume of combat casualties have benefited from adoption of regenerative medicine therapies and increased access to innovative clinical trials. Furthermore, many of these patients have had long-term follow-up to report

  20. Plastic Surgery Challenges in War Wounded II: Regenerative Medicine.

    PubMed

    Valerio, Ian L; Sabino, Jennifer M; Dearth, Christopher L

    2016-09-01

    Background: A large volume of service members have sustained complex injuries during Operations Iraqi Freedom (OIF) and Enduring Freedom (OEF). These injuries are complicated by contamination with particulate and foreign materials, have high rates of bacterial and/or fungal infections, are often composite-type defects with massive soft tissue wounds, and usually have multisystem involvement. While traditional treatment modalities remain a mainstay for optimal wound care, traditional reconstruction approaches alone may be inadequate to fully address the scope and magnitude of such massive complex wounds. As a result of these difficult clinical problems, the use of regenerative medicine therapies, such as autologous adipose tissue grafting, stem cell therapies, nerve allografts, and dermal regenerate templates/extracellular matrix scaffolds, is increased as adjuncts to traditional reconstructive measures. Basic and Clinical Science Advances: The beneficial applications of regenerative medicine therapies have been well characterized in both in vitro studies and in vivo animal studies. The use of these regenerative medicine techniques in the treatment of combat casualty injuries has been increasing throughout the recent war conflicts. Clinical Care Relevance: Military medicine has shown positive results when utilizing certain regenerative medicine modalities in treating complex war wounds. As a result, multi-institution clinical trials are underway to further evaluate these observations and reconstruction measures. Conclusion: Successful combat casualty wound care often requires a combination of traditional aspects of the reconstructive ladder/elevator with adoption of various regenerative medicine therapies. Due to the recent OIF/OEF conflicts, a high volume of combat casualties have benefited from adoption of regenerative medicine therapies and increased access to innovative clinical trials. Furthermore, many of these patients have had long-term follow-up to report

  1. [Current possibilities of examination and preservative treatment in endometrial hyperplasia].

    PubMed

    Kołodziejczak, Małgorzata; Knapp, Paweł; Kuźmicki, Mariusz; Knapp, Piotr

    2011-07-01

    Endometrial hyperplasia is one of the most frequent reasons of pre- and menopausal bleeding. In recent years, knowledge of biology of hyperplastic endometrium has changed some medical guidelines in a group of patients diagnosed with endometrial lesions. In many cases radical procedures have been replaced with preservative treatment, especially for those women who wished to spare their uterus. Also, in many high-risk surgical procedures there are a number of algorithms which allow to perform non-radical treatment in those cases. Enforcement of those strategy should be linked to precise examination of endometrium morphology Summarizing, a preservative treatment in case of endometrial hyperplasia needs sensitive and specific tests which determine safety limits of the procedure. This paper has presented current possibilities of examination and non-radical treatment of endometrial hyperplasia.

  2. Congenital Hemifacial Hyperplasia: Clinical Presentation and Literature Review.

    PubMed

    Shanmugasundaram, Karpagavalli; Vedam, V K Vaishnavi; Ganapathy, Sivadas; Sathish, Sivan; Satti, Parvathi

    2016-01-01

    Hemifacial hyperplasia is a rare congenital malformation characterized by noticeable unilateral excess development of hard and soft tissues of the face. Asymmetry in Congenital Hemifacial Hyperplasia (CHH) is usually evident at birth and accentuated at the age of puberty. The affected side grows exponentially as compared to the unaffected side. Multiple tissue involvement has resulted due to etiological heterogeneity like heredity, chromosomal abnormalities, altered intrauterine environment, and endocrine dysfunctions. As this lesion is rarely seen in our routine clinical practice, we present a case of hemifacial hyperplasia with reported orofacial features that supplement existing clinical knowledge. This paper also adds knowledge to the readers regarding detailed investigation procedures which has complemented our diagnosis. Further emphasis has been placed on periodic approach to its diagnosis and multidisciplinary management following correct diagnosis.

  3. Pathophysiology and management of endometrial hyperplasia and carcinoma.

    PubMed Central

    Fu, Y. S.; Gambone, J. C.; Berek, J. S.

    1990-01-01

    Endometrial cancer is currently the commonest pelvic malignancy affecting American women, most of whom share the same pathophysiologic basis, that is, unopposed estrogenic stimulation. The initial result of hyperestrogenism is the development of endometrial hyperplasia, which is reversible in most cases by appropriate hormonal therapy. Persistent stimulation eventually leads to atypical hyperplasia with nuclear atypia and invasive carcinoma. Because there is no cost-effective screening method for the detection of endometrial hyperplasia and carcinoma, it is essential to survey the high-risk population with appropriate diagnostic techniques. After diagnosis, therapy should be individualized based on pathologic findings (cell type and histologic grade) and extent of disease (International Federation of Gynaecologists and Obstetricians stage, depth of myometrial invasion, and pelvic and para-aortic lymph node status). Recent studies suggest that sex hormone receptors and nuclear DNA ploidy patterns provide useful prognostic information independent of histologic grade. Images PMID:2202159

  4. Congenital Hemifacial Hyperplasia: Clinical Presentation and Literature Review

    PubMed Central

    Shanmugasundaram, Karpagavalli; Ganapathy, Sivadas; Sathish, Sivan; Satti, Parvathi

    2016-01-01

    Hemifacial hyperplasia is a rare congenital malformation characterized by noticeable unilateral excess development of hard and soft tissues of the face. Asymmetry in Congenital Hemifacial Hyperplasia (CHH) is usually evident at birth and accentuated at the age of puberty. The affected side grows exponentially as compared to the unaffected side. Multiple tissue involvement has resulted due to etiological heterogeneity like heredity, chromosomal abnormalities, altered intrauterine environment, and endocrine dysfunctions. As this lesion is rarely seen in our routine clinical practice, we present a case of hemifacial hyperplasia with reported orofacial features that supplement existing clinical knowledge. This paper also adds knowledge to the readers regarding detailed investigation procedures which has complemented our diagnosis. Further emphasis has been placed on periodic approach to its diagnosis and multidisciplinary management following correct diagnosis. PMID:27843653

  5. Smoking habits and benign prostatic hyperplasia

    PubMed Central

    Xu, Huan; Fu, Shi; Chen, Yanbo; Chen, Qi; Gu, Meng; Wang, Zhong

    2016-01-01

    Abstract Previous studies have warned against the promoting effects of cigarette smoking on benign prostatic hyperplasia (BPH). In contrast, some have argued that smoking confers a protective effect regarding BPH, while others have observed an aggravated effect. Thus, we performed this meta-analysis to determine whether cigarette use is associated with BPH risk. To identify articles from observational studies of relevance, a search was performed concurrent to March 21, 2016, on PubMed, Web of Science, Cochrane, EBSCO, and EMBASE databases. Random-effect model, according to the heterogeneity, was calculated to reveal the relative risks (RRs) and corresponding 95% confidence intervals (CIs). Eight articles were included in this meta-analysis, representing data for 44,100 subjects, of which 5221 (11.8%) had BPH as defined according to the criteria. Seven reports are concerned with analysis between nonsmokers and ex-smokers, in which no significant difference was observed (RR = 0.99, 95% CI 0.94–1.05). Another meta-analysis of 7 studies indicated an observable trend, but without significant difference between groups of nonsmokers and current smokers (RR = 1.17, 95% CI 0.98–1.41). Between groups of heavy (6 articles; RR = 1.02, 95% CI 0.84–1.24) and light smokers (5 articles; RR = 0.90, 95% CI 0.71–1.15), again no significant difference appears. Finally, we combined individuals as never-smokers and ever-smokers and still found no significant difference between the 2 groups of patients (RR = 1.03, 95% CI 0.92–1.15). Sensitivity analysis was displayed and confirmed the stability of the present results. Combined evidence from observational studies shows no significant association between cigarette smoking and BPH risk, either for ex-smokers or for current smokers. The trend of elevated BPH risk from smoking was observed only in current smokers compared with nonsmokers, while marginal significance was observed in comparing ever-smokers with

  6. An Extensive Denture-Induced Hyperplasia of Maxilla

    PubMed Central

    Veena, KM; Jagadishchandra, H; Sequria, J; Hameed, SK; Chatra, L; Shenai, P

    2013-01-01

    Denture-induced hyperplasia is a reactive lesion arising from excessive and chronic mechanical pressure on the vestibular oral mucosa. It has a female predilection and it is mostly seen in the maxilla. The size of the lesion may be as small as a few millimeters to massive lesion involving the entire vestibule. It is usually asymptomatic but sometimes severe inflammation and ulceration can occur. Elimination of the inflammation and excision of the lesion is the treatment of choice. Denture induced hyperplasia in right maxillary buccal vestibule in a middle age old female patient was presented. Surgical excision was done and new denture was fabricated. PMID:24349860

  7. Oral focal epithelial hyperplasia: report of five cases.

    PubMed

    Borborema-Santos, Cristina Maria; Castro, Maria Marta de; Santos, Paulo José Benevides dos; Talhari, Sinésio; Astolfi-Filho, Spartaco

    2006-01-01

    Focal epithelial hyperplasia or Heck's disease is a rare contagious disease caused by human papillomavirus types 13 or 32, initially described among Native American populations. This condition is characterized by the occurrence of multiple small papules or nodules in oral cavity, especially on labial and buccal mucosa and tongue. This report describes the diagnosis of focal epithelial hyperplasia in five Central Amazonian Indians who sought treatment at the Amazonas State Foundation of Tropical Medicine (FMT-AM), using clinical criteria, polymerase chain reaction (PCR) and DNA sequencing.

  8. Prostate Artery Embolization for Benign Prostatic Hyperplasia: Current Status.

    PubMed

    Mirakhur, Anirudh; McWilliams, Justin P

    2017-02-01

    Prostate artery embolization has garnered much attention as a promising treatment for lower urinary tract symptoms secondary to benign prostatic hyperplasia. We aim to provide an up-to-date review of this minimally invasive technique, including discussion of potential benefits and technical challenges. Current evidence suggests it is a safe and effective option for patients with medication-refractory urinary obstructive symptoms who are poor surgical candidates or refuse surgical therapy. Larger, randomized studies with long-term follow-up data are needed for this technique to be formally established in the treatment paradigm for benign prostatic hyperplasia.

  9. Advanced biomatrix designs for regenerative therapy of periodontal tissues.

    PubMed

    Kim, J H; Park, C H; Perez, R A; Lee, H Y; Jang, J H; Lee, H H; Wall, I B; Shi, S; Kim, H W

    2014-12-01

    Periodontitis is an inflammatory disease that causes loss of the tooth-supporting apparatus, including periodontal ligament, cementum, and alveolar bone. A broad range of treatment options is currently available to restore the structure and function of the periodontal tissues. A regenerative approach, among others, is now considered the most promising paradigm for this purpose, harnessing the unique properties of stem cells. How to make full use of the body's innate regenerative capacity is thus a key issue. While stem cells and bioactive factors are essential components in the regenerative processes, matrices play pivotal roles in recapitulating stem cell functions and potentiating therapeutic actions of bioactive molecules. Moreover, the positions of appropriate bioactive matrices relative to the injury site may stimulate the innate regenerative stem cell populations, removing the need to deliver cells that have been manipulated outside of the body. In this topical review, we update views on advanced designs of biomatrices-including mimicking of the native extracellular matrix, providing mechanical stimulation, activating cell-driven matrices, and delivering bioactive factors in a controllable manner-which are ultimately useful for the regenerative therapy of periodontal tissues.

  10. A Novel Unitized Regenerative Proton Exchange Membrane Fuel Cell

    NASA Technical Reports Server (NTRS)

    Murphy, O. J.; Cisar, A. J.; Gonzalez-Martin, A.; Salinas, C. E.; Simpson, S. F.

    1996-01-01

    A difficulty encountered in designing a unitized regenerative proton exchange membrane (PEM) fuel cell lies in the incompatibility of electrode structures and electrocatalyst materials optimized for either of the two functions (fuel cell or electrolyzer) with the needs of the other function. This difficulty is compounded in previous regenerative fuel cell designs by the fact that water, which is needed for proton conduction in the PEM during both modes of operation, is the reactant supplied to the anode in the electrolyzer mode of operation and the product formed at the cathode in the fuel cell mode. Drawbacks associated with existing regenerative fuel cells have been addressed. In a first innovation, electrodes function either as oxidation electrodes (hydrogen ionization or oxygen evolution) or as reduction electrodes (oxygen reduction or hydrogen evolution) in the fuel cell and electrolyzer modes, respectively. Control of liquid water within the regenerative fuel cell has been brought about by a second innovation. A novel PEM has been developed with internal channels that permit the direct access of water along the length of the membrane. Lateral diffusion of water along the polymer chains of the PEM provides the water needed at electrode/PEM interfaces. Fabrication of the novel single cell unitized regenerative fuel cell and results obtained on testing it are presented.

  11. A novel unitized regenerative proton exchange membrane fuel cell

    NASA Technical Reports Server (NTRS)

    Murphy, O. J.; Cisar, A. J.; Gonzalez-Martin, A.; Salinas, C. E.; Simpson, S. F.

    1995-01-01

    A difficulty encountered in designing a unitized regenerative proton exchange membrane (PEM) fuel cell lies in the incompatibility of electrode structures and electrocatalyst materials optimized for either of the two functions (fuel cell or electrolyzer) with the needs of the other function. This difficulty is compounded in previous regenerative fuel cell designs by the fact that water, which is needed for proton conduction in the PEM during both modes of operation, is the reactant supplied to the anode in the electrolyzer mode of operation and the product formed at the cathode in the fuel cell mode. Drawbacks associated with existing regenerative fuel cells have been addressed in work performed at Lynntech. In a first innovation, electrodes function either as oxidation electrodes (hydrogen ionization or oxygen evolution) or as reduction electrodes (oxygen reduction or hydrogen evolution) in the fuel cell and electrolyzer modes, respectively. Control of liquid water within the regenerative fuel cell has been brought about by a second innovation. A novel PEM has been developed with internal channels that permit the direct access of water along the length of the membrane. Lateral diffusion of water along the polymer chains of the PEM provides the water needed at electrode/PEM interfaces. Fabrication of the novel unitized regenerative fuel cell and results obtained on testing it will be presented.

  12. Regenerative Medicine: Charting a New Course in Wound Healing

    PubMed Central

    Gurtner, Geoffrey C.; Chapman, Mary Ann

    2016-01-01

    Significance: Chronic wounds are a prevalent and costly problem in the United States. Improved treatments are needed to heal these wounds and prevent serious complications such as infection and amputation. Recent Advances: In wound healing, as in other areas of medicine, technologies that have the potential to regenerate as opposed to repair tissue are gaining ground. These include customizable nanofiber matrices incorporating novel materials; a variety of autologous and allogeneic cell types at various stages of differentiation (e.g., pluripotent, terminally differentiated); peptides; proteins; small molecules; RNA inhibitors; and gene therapies. Critical Issues: Wound healing is a logical target for regenerative medicine due to the accessibility and structure of skin, the regenerative nature of healing, the lack of good limb salvage treatments, and the current use of cell therapies. However, more extensive knowledge of pathophysiologic targets is needed to inform regenerative strategies, and new technologies must demonstrate value in terms of outcomes and related health economic measures to achieve successful market access and penetration. Future Directions: Due to similarities in cell pathways and developmental mechanisms, regenerative technologies developed in one therapeutic area may be applicable to others. Approaches that proceed from human genomic or other big data sources to models are becoming increasingly common and will likely suggest novel therapeutic avenues. To fully capitalize on the advances in regenerative medicine, studies must demonstrate the value of new therapies in identified patient populations, and sponsors must work with regulatory agencies to develop appropriate dossiers supporting timely approval. PMID:27366592

  13. Erich Regener and the ionisation maximum of the atmosphere

    NASA Astrophysics Data System (ADS)

    Carlson, P.; Watson, A. A.

    2014-12-01

    In the 1930s the German physicist Erich Regener (1881-1955) did important work on the measurement of the rate of production of ionisation deep under water and in the atmosphere. Along with one of his students, Georg Pfotzer, he discovered the altitude at which the production of ionisation in the atmosphere reaches a maximum, often, but misleadingly, called the Pfotzer maximum. Regener was one of the first to estimate the energy density of cosmic rays, an estimate that was used by Baade and Zwicky to bolster their postulate that supernovae might be their source. Yet Regener's name is less recognised by present-day cosmic ray physicists than it should be, largely because in 1937 he was forced to take early retirement by the National Socialists as his wife had Jewish ancestors. In this paper we briefly review his work on cosmic rays and recommend an alternative naming of the ionisation maximum. The influence that Regener had on the field through his son, his son-in-law, his grandsons and his students, and through his links with Rutherford's group in Cambridge, is discussed in an appendix. Regener was nominated for the Nobel Prize in Physics by Schrödinger in 1938. He died in 1955 at the age of 73.

  14. TOPICAL REVIEW: Cell and biomolecule delivery for regenerative medicine

    NASA Astrophysics Data System (ADS)

    Smith, Ian O.; Ma, Peter X.

    2010-02-01

    Regenerative medicine is an exciting field that aims to create regenerative alternatives to harvest tissues for transplantation. In this approach, the delivery of cells and biological molecules plays a central role. The scaffold (synthetic temporary extracellular matrix) delivers cells to the regenerative site and provides three-dimensional environments for the cells. To fulfil these functions, we design biodegradable polymer scaffolds with structural features on multiple size scales. To enhance positive cell-material interactions, we design nano-sized structural features in the scaffolds to mimic the natural extracellular matrix. We also integrate micro-sized pore networks to facilitate mass transport and neo tissue regeneration. We also design novel polymer devices and self-assembled nanospheres for biomolecule delivery to recapitulate key events in developmental and wound healing processes. Herein, we present recent work in biomedical polymer synthesis, novel processing techniques, surface engineering and biologic delivery. Examples of enhanced cellular/tissue function and regenerative outcomes of these approaches are discussed to demonstrate the excitement of the biomimetic scaffold design and biologic delivery in regenerative medicine.

  15. Regenerative Endodontics: Barriers and Strategies for Clinical Translation

    PubMed Central

    Kim, Sahng G.; Zhou, Jian; Ye, Ling; Cho, Shoko; Suzuki, Takahiro; Fu, Susan Y.; Yang, Rujing; Zhou, Xuedong; Mao, Jeremy J.

    2014-01-01

    SYNOPSIS Despite a great deal of enthusiasm and effort, regenerative endodontics has encountered substantial challenges towards clinical translation. Recent adoption by the American Dental Association (ADA) of evoked pulp bleeding in immature permanent teeth is an important step for regenerative endodontics. However, there is no regenerative therapy for the majority of endodontic diseases. Simple recapitulation of cell therapy and tissue engineering strategies that are under development for other organ systems has not led to clinical translation in regeneration endodontics. Dental pulp stem cells may appear to be a priori choice for dental pulp regeneration. However, dental pulp stem cells may not be available in a patient who is in need of pulp regeneration. Even if dental pulp stem cells are available autologously or perhaps allogeneically, one must address a multitude of scientific, regulatory and commercialization barriers, and unless these issues are resolved, transplantation of dental pulp stem cells will remain a scientific exercise, rather than a clinical reality. Recent work using novel biomaterial scaffolds and growth factors that orchestrate the homing of host endogenous cells represents a departure from traditional cell transplantation approaches and may accelerate clinical translation. Given the functions and scale of dental pulp and dentin, regenerative endodontics is poised to become one of the early biological solutions in regenerative dental medicine. PMID:22835543

  16. The continued promise of stem cell therapy in regenerative medicine.

    PubMed

    Eve, David J

    2011-12-01

    The use of stem cells is galvanizing regenerative medicine research. An analysis of recent trends as typified by articles published between 2009 and 2010 in the journals Cell Transplantation--The Regenerative Medicine Journal and Medical Science Monitor demonstrate the increasing importance of stem cell research as being on the cutting edge of regenerative medicine research. The analysis revealed an even split between transplantation and non-transplantation studies, showing that both the applicability and general research is being pursued. New methods and tissue engineering are also highly important components of regenerative medicine as demonstrated by a number of the stem cell studies being involved with either ex vivo manipulation, or cotransplantation with other cells or biomaterials. This suggests that the best results may be achieved with adjuvant therapies. The non-transplantation studies were more focused on manipulation of transplantable agents including cells and scaffold systems, as well as the use of medicines and dietary supplements. The further elucidation of disease mechanisms was a major contribution. This analysis suggests that regenerative medicine is proceeding at a rapid pace and the next few years should be of considerable interest with the initial results of pioneering stem cell therapies being announced.

  17. Stem cells have the potential to rejuvenate regenerative medicine research.

    PubMed

    Eve, David J; Fillmore, Randolph; Borlongan, Cesar V; Sanberg, Paul R

    2010-10-01

    The increasing number of publications featuring the use of stem cells in regenerative processes supports the idea that they are revolutionizing regenerative medicine research. In an analysis of the articles published in the journal Cell Transplantation - The Regenerative Medicine Journal between 2008 and 2009, which reveals the topics and categories that are on the cutting edge of regenerative medicine research, stem cells are becoming increasingly relevant as the "runner-up" category to "neuroscience" related articles. The high volume of stem cell research casts a bright light on the hope for stem cells and their role in regenerative medicine as a number of reports deal with research using stem cells entering, or seeking approval for, clinical trials. The "methods and new technologies" and "tissue engineering" sections were almost equally as popular, and in part, reflect attempts to maximize the potential of stem cells and other treatments for the repair of damaged tissue. Transplantation studies were again more popular than non-transplantation, and the contribution of stem cell-related transplants was greater than other types of transplants. The non-transplantation articles were predominantly related to new methods for the preparation, isolation and manipulation of materials for transplant by specific culture media, gene therapy, medicines, dietary supplements, and co-culturing with other cells and further elucidation of disease mechanisms. A sizeable proportion of the transplantation articles reported on how previously new methods may have aided the ability of the cells or tissue to exert beneficial effects following transplantation.

  18. Repairing quite swimmingly: advances in regenerative medicine using zebrafish

    PubMed Central

    Goessling, Wolfram; North, Trista E.

    2014-01-01

    Regenerative medicine has the promise to alleviate morbidity and mortality caused by organ dysfunction, longstanding injury and trauma. Although regenerative approaches for a few diseases have been highly successful, some organs either do not regenerate well or have no current treatment approach to harness their intrinsic regenerative potential. In this Review, we describe the modeling of human disease and tissue repair in zebrafish, through the discovery of disease-causing genes using classical forward-genetic screens and by modulating clinically relevant phenotypes through chemical genetic screening approaches. Furthermore, we present an overview of those organ systems that regenerate well in zebrafish in contrast to mammalian tissue, as well as those organs in which the regenerative potential is conserved from fish to mammals, enabling drug discovery in preclinical disease-relevant models. We provide two examples from our own work in which the clinical translation of zebrafish findings is either imminent or has already proven successful. The promising results in multiple organs suggest that further insight into regenerative mechanisms and novel clinically relevant therapeutic approaches will emerge from zebrafish research in the future. PMID:24973747

  19. Proteins and Small Molecules for Cellular Regenerative Medicine

    PubMed Central

    Green, Eric M.

    2013-01-01

    Regenerative medicine seeks to understand tissue development and homeostasis and build on that knowledge to enhance regeneration of injured tissues. By replenishing lost functional tissues and cells, regenerative medicine could change the treatment paradigm for a broad range of degenerative and ischemic diseases. Multipotent cells hold promise as potential building blocks for regenerating lost tissues, but successful tissue regeneration will depend on comprehensive control of multipotent cells–differentiation into a target cell type, delivery to a desired tissue, and integration into a durable functional structure. At each step of this process, proteins and small molecules provide essential signals and, in some cases, may themselves act as effective therapies. Identifying these signals is thus a fundamental goal of regenerative medicine. In this review we discuss current progress using proteins and small molecules to regulate tissue regeneration, both in combination with cellular therapies and as monotherapy. PMID:23303911

  20. Immunosuppression-free transplantation reconsidered from a regenerative medicine perspective.

    PubMed

    Orlando, Giuseppe

    2012-02-01

    Recent groundbreaking progress in regenerative medicine has shown its potential to meet the two major needs of solid organ transplantation, namely the achievement of an immunosuppression-free state (IFS) and the identification of a new, potentially inexhaustible source of organs. This review illustrates how regenerative medicine technology may contribute to the achievement of IFS. There are three possible strategies: organ bioengineering, immuno-isolation and thymus bioengineering. The goal of organ bioengineering is to manufacture organs ex vivo from autologous cells. Immuno-isolation technology implements strategies aiming to prevent recognition of nonself antigens by the host immune system. Thymus organoids have been bioengineered with scaffold-seeding methods to allow deletion of T-cell clones responsible for allograft rejection. Despite the several hurdles that must be overcome, regenerative medicine technologies offer alternative strategies aimed at establishing immediate, stable and durable IFS in solid organ graft recipients.

  1. Nanotechnology and regenerative therapeutics in plastic surgery: The next frontier

    PubMed Central

    Tan, Aaron; Chawla, Reema; Natasha, G; Mahdibeiraghdar, Sara; Jeyaraj, Rebecca; Rajadas, Jayakumar; Hamblin, Michael R.; Seifalian, Alexander M.

    2015-01-01

    Summary The rapid ascent of nanotechnology and regenerative therapeutics as applied to medicine and surgery has seen an exponential rise in the scale of research generated in this field. This is evidenced not only by the sheer volume of papers dedicated to nanotechnology but also in a large number of new journals dedicated to nanotechnology and regenerative therapeutics specifically to medicine and surgery. Aspects of nanotechnology that have already brought benefits to these areas include advanced drug delivery platforms, molecular imaging and materials engineering for surgical implants. Particular areas of interest include nerve regeneration, burns and wound care, artificial skin with nanoelectronic sensors and head and neck surgery. This study presents a review of nanotechnology and regenerative therapeutics, with focus on its applications and implications in plastic surgery. PMID:26422652

  2. Regenerative nanomedicine and the treatment of degenerative retinal diseases.

    PubMed

    Zarbin, Marco A; Montemagno, Carlo; Leary, James F; Ritch, Robert

    2012-01-01

    Regenerative medicine deals with the repair or the replacement of tissues and organs using advanced materials and methodologies. Regenerative nanomedicine uses nanoparticles containing gene transcription factors and other modulating molecules that allow reprogramming of cells in vivo as well as nanomaterials to induce selective differentiation of neural progenitor cells and to create neural-mechanical interfaces. In this article, we consider some applications of nanotechnology that may be useful for the treatment of degenerative retinal diseases, for example, use of nanoparticles for drug and gene therapy, use of nanomaterials for neural interfaces and extracellular matrix construction for cell-based therapy and neural prosthetics, and the use of bionanotechnology to re-engineer proteins and cell behavior for regenerative medicine.

  3. Lightweight pressure vessels and unitized regenerative fuel cells

    SciTech Connect

    Mitlitsky, F.; Myers, B.; Weisberg, A.H.

    1996-09-06

    Energy storage systems have been designed using lightweight pressure vessels with unitized regenerative fuel cells (URFCs). The vessels provide a means of storing reactant gases required for URFCs; they use lightweight bladder liners that act as inflatable mandrels for composite overwrap and provide a permeation barrier. URFC systems have been designed for zero emission vehicles (ZEVs); they are cost competitive with primary FC powered vehicles that operate on H/air with capacitors or batteries for power peaking and regenerative braking. URFCs are capable of regenerative braking via electrolysis and power peaking using low volume/low pressure accumulated oxygen for supercharging the power stack. URFC ZEVs can be safely and rapidly (<5 min.) refueled using home electrolysis units. Reversible operation of cell membrane catalyst is feasible without significant degradation. Such systems would have a rechargeable specific energy > 400 Wh/kg.

  4. Genetically modified cells in regenerative medicine and tissue engineering.

    PubMed

    Sheyn, Dima; Mizrahi, Olga; Benjamin, Shimon; Gazit, Zulma; Pelled, Gadi; Gazit, Dan

    2010-06-15

    Regenerative medicine appears to take as its patron, the Titan Prometheus, whose liver was able to regenerate daily, as the field attempts to restore lost, damaged, or aging cells and tissues. The tremendous technological progress achieved during the last decade in gene transfer methods and imaging techniques, as well as recent increases in our knowledge of cell biology, have opened new horizons in the field of regenerative medicine. Genetically engineered cells are a tool for tissue engineering and regenerative medicine, albeit a tool whose development is fraught with difficulties. Gene-and-cell therapy offers solutions to severe problems faced by modern medicine, but several impediments obstruct the path of such treatments as they move from the laboratory toward the clinical setting. In this review we provide an overview of recent advances in the gene-and-cell therapy approach and discuss the main hurdles and bottlenecks of this approach on its path to clinical trials and prospective clinical practice.

  5. Gene delivery in tissue engineering and regenerative medicine.

    PubMed

    Fang, Y L; Chen, X G; W T, Godbey

    2015-11-01

    As a promising strategy to aid or replace tissue/organ transplantation, gene delivery has been used for regenerative medicine applications to create or restore normal function at the cell and tissue levels. Gene delivery has been successfully performed ex vivo and in vivo in these applications. Excellent proliferation capabilities and differentiation potentials render certain cells as excellent candidates for ex vivo gene delivery for regenerative medicine applications, which is why multipotent and pluripotent cells have been intensely studied in this vein. In this review, gene delivery is discussed in detail, along with its applications to tissue engineering and regenerative medicine. A definition of a stem cell is compared to a definition of a stem property, and both provide the foundation for an in-depth look at gene delivery investigations from a germ lineage angle.

  6. 25th Anniversary Article: Supramolecular Materials for Regenerative Medicine

    PubMed Central

    Boekhoven, Job

    2014-01-01

    In supramolecular materials, molecular building blocks are designed to interact with one another via non-covalent interactions in order to create function. This offers the opportunity to create structures similar to those found in living systems that combine order and dynamics through the reversibility of intermolecular bonds. For regenerative medicine there is a great need to develop materials that signal cells effectively, deliver or bind bioactive agents in vivo at controlled rates, have highly tunable mechanical properties, but at the same time, can biodegrade safely and rapidly after fulfilling their function. These requirements make supramolecular materials a great platform to develop regenerative therapies. This review illustrates the emerging science of these materials and their use in a number of applications for regenerative medicine. PMID:24496667

  7. Electric vehicle regenerative antiskid braking and traction control system

    SciTech Connect

    Cikanek, Susan R.

    1995-01-01

    An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydrualic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control.

  8. Electric vehicle regenerative antiskid braking and traction control system

    SciTech Connect

    Cikanek, S.R.

    1995-09-12

    An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydraulic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control. 10 figs.

  9. Nanotechnology and regenerative therapeutics in plastic surgery: The next frontier.

    PubMed

    Tan, Aaron; Chawla, Reema; G, Natasha; Mahdibeiraghdar, Sara; Jeyaraj, Rebecca; Rajadas, Jayakumar; Hamblin, Michael R; Seifalian, Alexander M

    2016-01-01

    The rapid ascent of nanotechnology and regenerative therapeutics as applied to medicine and surgery has seen an exponential rise in the scale of research generated in this field. This is evidenced not only by the sheer volume of papers dedicated to nanotechnology but also in a large number of new journals dedicated to nanotechnology and regenerative therapeutics specifically to medicine and surgery. Aspects of nanotechnology that have already brought benefits to these areas include advanced drug delivery platforms, molecular imaging and materials engineering for surgical implants. Particular areas of interest include nerve regeneration, burns and wound care, artificial skin with nanoelectronic sensors and head and neck surgery. This study presents a review of nanotechnology and regenerative therapeutics, with focus on its applications and implications in plastic surgery.

  10. Biomarkers of progestin therapy resistance and endometrial hyperplasia progression

    PubMed Central

    Upson, Kristen; Allison, Kimberly H.; Reed, Susan D.; Jordan, Carolyn D.; Newton, Katherine M.; Swisher, Elizabeth M.; Doherty, Jennifer A.; Garcia, Rochelle L.

    2012-01-01

    Objective To identify biomarkers associated with progestin therapy resistance and persistence/progression of endometrial hyperplasia. Study Design We performed a nested case-control study among women with complex (n=73) and atypical (n=41) hyperplasia treated with oral progestin, followed 2–6 months for persistence/progression. We evaluated index endometrial protein expression for progesterone receptors A (PRA) and B (PRB), PTEN, Pax-2 and Bcl-2. Odds ratios and 95% confidence intervals were estimated. Results Among women with atypical hyperplasia, high PRB expression was associated with 90% decreased risk of persistence/progression (95% CI: 0.01–0.8). High expression of PRA and PRB suggested decreased risk of persistence/ progression (OR=0.1, 95% CI: 0.02–1.0). These findings were not observed among women with complex hyperplasia. No associations were found with PTEN, Pax-2, and Bcl-2 protein expression. Conclusions PRB expression shows promise as a biomarker of progestin response. Further research is warranted to understand how PRB expression may guide treatment decisions. PMID:22727345

  11. Thymic remodeling associated with hyperplasia in myasthenia gravis.

    PubMed

    Le Panse, Rozen; Bismuth, Jacky; Cizeron-Clairac, Géraldine; Weiss, Julia Miriam; Cufi, Perrine; Dartevelle, Philippe; De Rosbo, Nicole Kerlero; Berrih-Aknin, Sonia

    2010-08-01

    Acquired myasthenia gravis (MG), a neurological autoimmune disease, is caused by autoantibodies against components of the neuromuscular junction that lead to disabling muscle fatigability. The thymus is clearly involved in the pathogenesis of early-onset MG with anti-acetylcholine receptor antibodies, and thymic hyperplasia of lympho-proliferative origin is a hallmark of the disease. In this review, we describe the structural and cellular changes associated with thymic hyperplasia, its main characteristics being the development of ectopic germinal centers (GCs) associated with active neoangiogenic processes, such as development of high endothelial venules and lymphangiogenesis. What triggers such thymic abnormalities in MG is not yet clear. A thymic transcriptome analysis has demonstrated a strong inflammatory signature in MG that could orchestrate the development of thymic hyperplasia. In this context, thymic epithelial cells (TECs) seem to play a central role, either by contributing or responding to the inflammatory environment and up-regulating the autoimmune response. In particular, MG TECs clearly overexpress various cytokines, among which chemokines play a crucial role in the recruitment of peripheral lymphocytes to the thymus via the newly expanded vessel network, thereby leading to the development of ectopic GCs. Clearly, a better understanding of major events that lead to thymic hyperplasia will help optimize strategies toward more specific therapy for MG.

  12. [Focal epithelial hyperplasia (Heck's disease) in a Turkish family].

    PubMed

    Weidner, F

    1996-12-01

    A 31-year-old Turkish patient and some family members suffered from multiple hyperplastic oral mucosal papules. Intralesional papilloma virus was not found but the patient had elevated levels of CD8 lymphocytes in his peripheral blood. We diagnosed focal epithelial hyperplasia of Heck.

  13. Focal epithelial hyperplasia (Heck disease) associated with AIDS.

    PubMed

    Viraben, R; Aquilina, C; Brousset, P; Bazex, J

    1996-01-01

    Focal epithelial hyperplasia (FEH) of the oral mucosa occurring in a HIV-infected man is described. Molecular biology disclosed an HPV-32 type in oral lesions. The association of FEH and AIDS is uncommon although many HPV subtypes may manifest during HIV infection.

  14. Condylar hyperplasia: correlation of histological and scintigraphic features.

    PubMed

    Gray, R J; Horner, K; Testa, H J; Lloyd, J J; Sloan, P

    1994-05-01

    Scintigaphy using 99mTc-MDP is widely advocated as a method of diagnosis and presurgical assessment of patients with condylar hyperplasia. A previous study has demonstrated that hyperplasia of the mandibular condyle is characterized histologically by the presence of an uninterrupted layer of undiffentiated germinative mesenchyme cells, a layer of hypertrophic cartilage and the presence of islands of chondrocytes in the subchondral trabecular bone. This study was undertaken to determine whether there was any association between the degree of 99mTc-MDP uptake and the histological features of condylar hyperplasia. The parameters examined were trabecular bone volume, depth of cartilage islands and the presence of forming and resorbing surfaces. The images were analyzed by three experienced observers, who ranked the images according to degree of asymmetry between sides and the degree of uptake on the affected side. There was a significant correlation between the proportions of resorbing and osteoid covered bone surfaces and scintigraphic appearances. The rank correlations were rs = 0.55 (P = 0.3) between the resorptive surfaces and degree of symmetry and rs = 0.53 (P = 0.04) between the osteoid surfaces and absolute uptake. The correlation was higher for both methods (rs = 0.64 in each case) when the osteoid surface and resorptive surface measurements were combined. The results indicate that visual examination of radioisotope bone scans by experienced observers is a valid form of assessment of bone activity in condylar hyperplasia.

  15. Hyperplasia and Hypertrophy of Pacinian Corpuscles: A Case Report.

    PubMed

    García, Fernando Cano; Acosta, Dalia Rodríguez; Diaz González, José Manuel; Lima, Marcela Saeb

    2015-08-01

    The proliferation of Pacinian corpuscles is a rare benign lesion that occurs frequently in the fingers of hands, with the only clinical sign of pain when a drastic temperature change happens. A case of an extremely rare lesion in which we observed hypertrophy and hyperplasia of Pacinian corpuscles has been reported.

  16. Mistaken gender identity in non-classical congenital adrenal hyperplasia.

    PubMed

    Kukreti, Prerna; Kandpal, Manish; Jiloha, R C

    2014-04-01

    Gender identity is the sense of belonging that one feels for a particular sex psychologically and socially, independent of one's biological sex. There is much less systematic data on gender identity in females with congenital adrenal hyperplasia (CAH). We report a case of non-classical CAH presenting as a case of gender identity disorder.

  17. MX-INDUCED URINARY BLADDER EPITHELIAL HYPERPLASIA IN EKER RATS

    EPA Science Inventory

    MX-INDUCED URINARY BLADDER EPITHELIAL HYPERPLASIA IN EKER RATS

    Epidemiological studies have shown a positive association between chronic exposure to chlorinated drinking water and human cancer, particularly of the urinary bladder. MX (3- chloro-4-(dichloromethyl)-5-hydrox...

  18. Severe venous neointimal hyperplasia prior to dialysis access surgery

    PubMed Central

    Lee, Timmy; Chauhan, Vibha; Krishnamoorthy, Mahesh; Wang, Yang; Arend, Lois; Mistry, Meenakshi J.; El-Khatib, Mahmoud; Banerjee, Rupak; Munda, Rino; Roy-Chaudhury, Prabir

    2011-01-01

    Background. Venous neointimal hyperplasia is the most common cause of arteriovenous (AV) fistula and graft dysfunction following dialysis access surgery. However, the pathogenetic impact of pre-existing venous neointimal hyperplasia at the time of AV access creation on final clinical success is currently unknown in the setting of advanced chronic kidney disease (CKD) and end-stage renal disease (ESRD) patients. The aim of this study was to perform a detailed histological, morphometric, and immunohistochemical analysis of vein specimens in advanced CKD and ESRD patients collected at the time of new vascular access placement. Methods. Vein samples from 12 patients were collected at the time of AV access creation near the site of AV anastomosis. Histological, immunohistochemistry and morphometric studies were performed on these vein samples. Results. Examination of the tissue specimens obtained at the time of surgery showed neointimal hyperplasia in 10 of 12 specimens, ranging from minimal to very severe. The majority of cells within the neointima were myofibroblasts with a minority of contractile smooth muscle cells present. Conclusion. Our work represents a detailed description of the morphometric and cellular phenotypic lesions present in the veins of CKD and ESRD patients, prior to dialysis access placement. These studies (i) suggest the future possibility of a new predictive marker (pre-existing venous neointimal hyperplasia) for AV dialysis access dysfunction and (ii) open the door for the future development of novel local therapies for optimization of the venous substrate on which the dialysis access is created. PMID:21220751

  19. Mistaken gender identity in non-classical congenital adrenal hyperplasia

    PubMed Central

    Kukreti, Prerna; Kandpal, Manish; Jiloha, R. C.

    2014-01-01

    Gender identity is the sense of belonging that one feels for a particular sex psychologically and socially, independent of one's biological sex. There is much less systematic data on gender identity in females with congenital adrenal hyperplasia (CAH). We report a case of non-classical CAH presenting as a case of gender identity disorder. PMID:24891708

  20. Diffuse Neuroendocrine Cell Hyperplasia: Report of Two Cases

    PubMed Central

    Cansız Ersöz, Cevriye; Cangır, Ayten Kayı; Dizbay Sak, Serpil

    2016-01-01

    Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a rare pulmonary disorder characterised by a proliferation of neuroendocrine cells within the lung. It is believed that a minority of the patients with DIPNECH can develop carcinoid tumors. Here, we report two new cases of DIPNECH with coexisting carcinoid tumors. PMID:27293939

  1. [Bilateral hyperplasia of the coronoid apophyses. A clinical case].

    PubMed

    Parascandolo, S; Rusciano, A; Tamai, M; Morlino, M

    1993-03-01

    The authors report on the case of a young patient affected with bilateral hyperplasia of the coronoid apophyses, who presented a serious reduction of the mandibular excursion. Normal mouth opening was re-established by a bilateral osteotomy with endoral removal of the coronoid apophyses.

  2. Congenital adrenal hyperplasia with localized aggressive periodontitis and amelogenesis imperfecta.

    PubMed

    Ajlan, Sumaiah Abdulbaqi

    2015-11-01

    Congenital adrenal hyperplasia (CAH) is an inherited medical condition that implies defects in steroid biosynthesis. The dental findings of a female patient with CAH are reported. The patient suffered from severe periodontal tissue destruction, obvious enamel defects, as well as some occlusal problems. The management approach is presented and the possibility of interrelation of her dental findings with her medical condition is discussed.

  3. Regenerative medicine and organ transplantation: past, present, and future.

    PubMed

    Orlando, Giuseppe; Wood, Kathryn J; Stratta, Robert J; Yoo, James J; Atala, Anthony; Soker, Shay

    2011-06-27

    This overview traces the history of regenerative medicine pertinent to organ transplantation, illustrates potential clinical applications reported to date, and highlights progress achieved in the field of complex modular organ engineering. Regenerative medicine can now produce relatively simple tissues such as skin, bladders, vessels, urethras, and upper airways, whereas engineering or generation of complex modular organs remains a major challenge. Ex vivo organ engineering may benefit from complementary investigations in the fields of developmental biology and stem cells and transplantation before its full potential can be realized.

  4. Regenerative medicine and stem cell based drug discovery.

    PubMed

    Sakurada, Kazuhiro; McDonald, Fiona M; Shimada, Fumiki

    2008-01-01

    As William Shakespeare beautifully described, increasing age often causes loss of tissue and organ function. The increase in average life expectancy in many countries is generating an aging society and an increase in age-related health problems. Regenerative medicine is expected to be a powerful actor in this drama, and stem cell technology may hold the key to the development of innovative treatments for acute and chronic degenerative conditions. This Review surveys the present situation and some future prospects for regenerative medicine and stem cell based drug discovery.

  5. Reprogramming and transdifferentiation shift the landscape of regenerative medicine.

    PubMed

    Guo, Jingjing; Wang, Hu; Hu, Xingchang

    2013-10-01

    Regenerative medicine is a new interdisciplinary field in biomedical science, which aims at the repair or replacement of the defective tissue or organ by congenital defects, age, injury, or disease. Various cell-related techniques such as stem cell-based biotherapy are a hot topic in the current press, and stem cell research can help us to expand our understanding of development as well as the pathogenesis of disease. In addition, new technology such as reprogramming or dedifferentiation and transdifferentiation open a new area for regenerative medicine. Here we review new approaches of these technologies used for cell-based therapy and discuss future directions and challenges in the field of regeneration.

  6. Regenerative endodontics and tissue engineering: what the future holds?

    PubMed

    Goodis, Harold E; Kinaia, Bassam Michael; Kinaia, Atheel M; Chogle, Sami M A

    2012-07-01

    The work performed by researchers in regenerative endodontics and tissue engineering over the last decades has been superb; however, many questions remain to be answered. The basic biologic mechanisms must be elucidated that will allow the development of dental pulp and dentin in situ. Stress must be placed on the many questions that will lead to the design of effective, safe treatment options and therapies. This article discusses those questions, the answers to which may become the future of regenerative endodontics. The future remains bright, but proper support and patience are required.

  7. A high-power compact regenerative amplifier FEL

    SciTech Connect

    Nguyen, D.C.; Sheffield, R.L.; Fortgang, C.M.; Kinross-Wright, J.M.; Ebrahim, N.A.; Goldstein, J.C.

    1997-08-01

    The Regenerative Amplifier FEL (RAFEL) is a new FEL approach aimed at achieving the highest optical power from a compact rf-linac FEL. The key idea is to feed back a small fraction (< 10%) of the optical power into a high-gain ({approximately}10{sup 5} in single pass) wiggler to enable the FEL to reach saturation in a few passes. This paper summarizes the design of a high-power compact regenerative amplifier FEL and describes the first experimental demonstration of the RAFEL concept.

  8. Ignition feedback regenerative free electron laser (FEL) amplifier

    DOEpatents

    Kim, Kwang-Je; Zholents, Alexander; Zolotorev, Max

    2001-01-01

    An ignition feedback regenerative amplifier consists of an injector, a linear accelerator with energy recovery, and a high-gain free electron laser amplifier. A fraction of the free electron laser output is coupled to the input to operate the free electron laser in the regenerative mode. A mode filter in this loop prevents run away instability. Another fraction of the output, after suitable frequency up conversion, is used to drive the photocathode. An external laser is provided to start up both the amplifier and the injector, thus igniting the system.

  9. SIRT1 Limits Adipocyte Hyperplasia through c-Myc Inhibition.

    PubMed

    Abdesselem, Houari; Madani, Aisha; Hani, Ahmad; Al-Noubi, Muna; Goswami, Neha; Ben Hamidane, Hisham; Billing, Anja M; Pasquier, Jennifer; Bonkowski, Michael S; Halabi, Najeeb; Dalloul, Rajaa; Sheriff, Mohamed Z; Mesaeli, Nasrin; ElRayess, Mohamed; Sinclair, David A; Graumann, Johannes; Mazloum, Nayef A

    2016-01-29

    The expansion of fat mass in the obese state is due to increased adipocyte hypertrophy and hyperplasia. The molecular mechanism that drives adipocyte hyperplasia remains unknown. The NAD(+)-dependent protein deacetylase sirtuin 1 (SIRT1), a key regulator of mammalian metabolism, maintains proper metabolic functions in many tissues, counteracting obesity. Here we report that differentiated adipocytes are hyperplastic when SIRT1 is knocked down stably in mouse 3T3-L1 preadipocytes. This phenotype is associated with dysregulated adipocyte metabolism and enhanced inflammation. We also demonstrate that SIRT1 is a key regulator of proliferation in preadipocytes. Quantitative proteomics reveal that the c-Myc pathway is altered to drive enhanced proliferation in SIRT1-silenced 3T3-L1 cells. Moreover, c-Myc is hyperacetylated, levels of p27 are reduced, and cyclin-dependent kinase 2 (CDK2) is activated upon SIRT1 reduction. Remarkably, differentiating SIRT1-silenced preadipocytes exhibit enhanced mitotic clonal expansion accompanied by reduced levels of p27 as well as elevated levels of CCAAT/enhancer-binding protein β (C/EBPβ) and c-Myc, which is also hyperacetylated. c-Myc activation and enhanced proliferation phenotype are also found to be SIRT1-dependent in proliferating mouse embryonic fibroblasts and differentiating human SW872 preadipocytes. Reducing both SIRT1 and c-Myc expression in 3T3-L1 cells simultaneously does not induce the adipocyte hyperplasia phenotype, confirming that SIRT1 controls adipocyte hyperplasia through c-Myc regulation. A better understanding of the molecular mechanisms of adipocyte hyperplasia will open new avenues toward understanding obesity.

  10. DDS for anti-aging and regenerative medicine (review).

    PubMed

    Mizushima, Y; Hoshi, K

    2006-01-01

    In this paper we summarized, first the present status and history of the development of research in anti-aging and regenerative medicine in Japan, and secondly some of our research using DDS in the field of both medicine. The regenerative medicine has been developed in Japan by using the fund from the Government, particularly as the Millennium Project. While anti-aging medicine developed following the social interest on it in Japan and it was influenced by American Society (A4M). Next, we summarized our research on DDS for anti-aging and regenerative medicine. In most cases we used oily or solid nanoparticles as carriers of drug. Those particles have a property of both of targeting and slow release in the DDS technology. The two properties are important for anti-aging and regenerative medicine, since drugs have to be administered safely and for long time. We applied prostaglandin E1, granulocyte-colony stimulate factor (G-CSF), and retinoid into the systems.

  11. Regenerative Snubber For GTO-Commutated SCR Inverter

    NASA Technical Reports Server (NTRS)

    Rippel, Wally E.; Edwards, Dean B.

    1992-01-01

    Proposed regenerative snubbing circuit substituted for dissipative snubbing circuit in inverter based on silicon controlled rectifiers (SCR's) commutated by gate-turn-off thyristor (GTO). Intended to reduce loss of power that occurs in dissipative snubber. Principal criteria in design: low cost, simplicity, and reliability.

  12. A Regeneratively Cooled Thrust Chamber For The Fastrac Engine

    NASA Technical Reports Server (NTRS)

    Brown, Kendall K.; Sparks, Dave; Woodcock, Gordon

    2000-01-01

    Abstract This paper presents the development of a low-cost, regeneratively-cooled thrust chamber for the Fastrac engine. The chamber was fabricated using hydraformed copper tubing to form the coolant jacket and wrapped with a fiber reinforced polymer composite Material to form a structural jacket. The thrust chamber design and fabrication approach was based upon Space America. Inc.'s 12,000 lb regeneratively-cooled LOX/kerosene rocket engine. Fabrication of regeneratively cooled thrust chambers by tubewall construction dates back to the early US ballistic missile programs. The most significant innovations in this design was the development of a low-cost process for fabrication from copper tubing (nickel alloy was the usual practice) and use of graphite composite overwrap as the pressure containment, which yields an easily fabricated, lightweight pressure jacket around the copper tubes A regeneratively-cooled reusable thrust chamber can benefit the Fastrac engine program by allowing more efficient (cost and scheduler testing). A proof-of-concept test article has been fabricated and will he tested at Marshall Space Flight Center in the late Summer or Fall of 2000.

  13. Alkaline regenerative fuel cell systems for energy storage

    SciTech Connect

    Schubert, F.H.; Reid, M.A.; Martin, R.E.

    1981-01-01

    This paper presents the results of a preliminary design study of a Regenerative Fuel Cell Energy Storage system for application to future low-earth orbit space missions. This high energy density storage system is based on state-of-the-art alkaline electrolyte cell technology and incorporates dedicated fuel cell and electrolysis cell modules. 11 refs.

  14. Stem cell bioprinting for applications in regenerative medicine.

    PubMed

    Tricomi, Brad J; Dias, Andrew D; Corr, David T

    2016-11-01

    Many regenerative medicine applications seek to harness the biologic power of stem cells in architecturally complex scaffolds or microenvironments. Traditional tissue engineering methods cannot create such intricate structures, nor can they precisely control cellular position or spatial distribution. These limitations have spurred advances in the field of bioprinting, aimed to satisfy these structural and compositional demands. Bioprinting can be defined as the programmed deposition of cells or other biologics, often with accompanying biomaterials. In this concise review, we focus on recent advances in stem cell bioprinting, including performance, utility, and applications in regenerative medicine. More specifically, this review explores the capability of bioprinting to direct stem cell fate, engineer tissue(s), and create functional vascular networks. Furthermore, the unique challenges and concerns related to bioprinting living stem cells, such as viability and maintaining multi- or pluripotency, are discussed. The regenerative capacity of stem cells, when combined with the structural/compositional control afforded by bioprinting, provides a unique and powerful tool to address the complex demands of tissue engineering and regenerative medicine applications.

  15. Status of the Regenerative ECLS Water Recovery System

    NASA Technical Reports Server (NTRS)

    Carter, Donald Layne

    2010-01-01

    The regenerative Water Recovery System (WRS) has completed its first full year of operation on the International Space Station (ISS). The major assemblies included in this system are the Water Processor Assembly (WPA) and Urine Processor Assembly (UPA). This paper summarizes the on-orbit status as of May 2010, and describes the technical challenges encountered and lessons learned over the past year.

  16. Crewmember repairing the Regenerative Carbon Dioxide Removal System wiring.

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Mission Pilot Ken Bowersox, busy at work on the wiring harness for the Regenerative Carbon Dioxide Removal System located under the mid deck floor. Photo shows Bowersox splicing wires together to 'fool' a faulty sensor that caused the 'air conditioner' to shut down.

  17. Serenoa repens for benign prostatic hyperplasia

    PubMed Central

    Tacklind, James; MacDonald, Roderick; Rutks, Indy; Wilt, Timothy J

    2011-01-01

    Background Benign prostatic hyperplasia (BPH), a nonmalignant enlargement of the prostate, can lead to obstructive and irritative lower urinary tract symptoms (LUTS). The pharmacologic use of plants and herbs (phytotherapy) for the treatment of LUTS associated with BPH is common. The extract of the berry of the American saw palmetto, or dwarf palm plant, Serenoa repens (also known by its botanical name of Sabal serrulatum), is one of several phytotherapeutic agents available for the treatment of BPH. Objectives This systematic review aimed to assess the effects of Serenoa repens in the treatment of LUTS consistent with BPH. Search strategy Trials were searched in computerized general and specialized databases (MEDLINE, EMBASE, and The Cochrane Library), by checking bibliographies, and by handsearching the relevant literature. Selection criteria Trials were eligible if they (1) randomized men with symptomatic BPH to receive preparations of Serenoa repens (alone or in combination) for at least four weeks in comparison with placebo or other interventions, and (2) included clinical outcomes such as urologic symptom scales, symptoms, and urodynamic measurements. Eligibility was assessed by at least two independent observers. Data collection and analysis Information on patients, interventions, and outcomes was extracted by at least two independent reviewers using a standard form. The main outcome measure for comparing the effectiveness of Serenoa repens with placebo or other interventions was the change in urologic symptom-scale scores. Secondary outcomes included changes in nocturia and urodynamic measures. The main outcome measure for side effects or adverse events was the number of men reporting side effects. Main results In this update 9 new trials involving 2053 additional men (a 64.8% increase) have been included. For the main comparison - Serenoa repens versus placebo - 3 trials were added with 419 subjects and 3 endpoints (IPSS, peak urine flow, prostate size

  18. SPE (tm) regenerative hydrogen/oxygen fuel cells for extraterrestrial surface and microgravity applications

    NASA Technical Reports Server (NTRS)

    Mcelroy, J. F.

    1990-01-01

    Viewgraphs on SPE regenerative hydrogen/oxygen fuel cells for extraterrestrial surface and microgravity applications are presented. Topics covered include: hydrogen-oxygen regenerative fuel cell energy storage system; electrochemical cell reactions; SPE cell voltage stability; passive water removal SPE fuel cell; fuel cell performance; SPE water electrolyzers; hydrophobic oxygen phase separator; hydrophilic/electrochemical hydrogen phase separator; and unitized regenerative fuel cell.

  19. Planarians: an In Vivo Model for Regenerative Medicine.

    PubMed

    Karami, Ali; Tebyanian, Hamid; Goodarzi, Vahabodin; Shiri, Sajad

    2015-11-01

    The emergence of regenerative medicine has raised the hope of treating an extraordinary range of disease and serious injuries. Understanding the processes of cell proliferation, differentiation and pattern formation in regenerative organisms could help find ways to enhance the poor regenerative abilities shown by many other animals, including humans. Recently, planarians have emerged as an attractive model in which to study regeneration. These animals are considering as in vivo plate, during which we can study the behavior and characristics of stem cells in their own niche. A variety of characteristic such as: simplicity, easy to manipulate experimentally, the existence of more than 100 years of literature, makes these animals an extraordinary model for regenerative medicine researches. Among planarians free-living freshwater hermaphrodite Schmidtea mediterranea has emerged as a suitable model system because it displays robust regenerative properties and, unlike most other planarians, it is a stable diploid with a genome size of about 4.8×10(8) base pairs, nearly half that of other common planarians. Planarian regeneration involves two highly flexible systems: pluripotent neoblasts that can generate any new cell type and muscle cells that provide positional instructions for the regeneration of anybody region. neoblasts represent roughly 25~30 percent of all planarian cells and are scattered broadly through the parenchyma, being absent only from the animal head tips and the pharynx. Two models for neo-blast specification have been proposed; the naive model posits that all neoblasts are stem cells with the same potential and are a largely homogeneous population.

  20. Trends in biomedical engineering: focus on Regenerative Medicine.

    PubMed

    Asnaghi, M Adelaide; Candiani, Gabriele; Farè, Silvia; Fiore, Gianfranco B; Petrini, Paola; Raimondi, Manuela T; Soncini, Monica; Mantero, Sara

    2011-01-01

    Regenerative medicine is a critical frontier in biomedical and clinical research. The major progresses in the last few years were driven by a strong clinical need which could benefit from regenerative medicine outcomes for the treatment of a large number of conditions including birth defects, degenerative and neoplastic diseases, and traumatic injuries. Regenerative medicine applies the principles of engineering and life sciences to enhance the comprehension of the fundamental biological mechanisms underlying the structure-function relationships in physiologic and pathologic tissues and to accomplish alternative strategies for developing in vitro biological substitutes which are able to restore, maintain, or improve tissue, and organ function. This paper reviews selected approaches currently being investigated at Politecnico di Milano in the field of regenerative medicine. Specific tissue-oriented topics are divided in three sections according to each developmental stage: in vitro study, pre-clinical study, and clinical application. In vitro studies investigate the basic phenomena related to gene delivery, stem cell behavior, tissue regeneration, and to explore dynamic culture potentiality in different applications: cardiac and skeletal muscle, cartilage, hematopoietic system, peripheral nerve, and gene delivery. Specific fields of regenerative medicine, i.e., bone, blood vessels, and ligaments engineering have already reached the preclinical stage providing promising insights for further research towards clinical applications. The translation of the results obtained during in vitro and preclinical steps into clinical organ replacement is a very challenging issue, which can offer a valid alternative to fight morbidity, organ shortage, and ethical-social problems associated with allotransplantation as shown in the clinical case reported in this review.

  1. Mesenchymal stem cell secretome and regenerative therapy after cancer.

    PubMed

    Zimmerlin, Ludovic; Park, Tea Soon; Zambidis, Elias T; Donnenberg, Vera S; Donnenberg, Albert D

    2013-12-01

    Cancer treatment generally relies on tumor ablative techniques that can lead to major functional or disfiguring defects. These post-therapy impairments require the development of safe regenerative therapy strategies during cancer remission. Many current tissue repair approaches exploit paracrine (immunomodulatory, pro-angiogenic, anti-apoptotic and pro-survival effects) or restoring (functional or structural tissue repair) properties of mesenchymal stem/stromal cells (MSC). Yet, a major concern in the application of regenerative therapies during cancer remission remains the possible triggering of cancer recurrence. Tumor relapse implies the persistence of rare subsets of tumor-initiating cancer cells which can escape anti-cancer therapies and lie dormant in specific niches awaiting reactivation via unknown stimuli. Many of the components required for successful regenerative therapy (revascularization, immunosuppression, cellular homing, tissue growth promotion) are also critical for tumor progression and metastasis. While bi-directional crosstalk between tumorigenic cells (especially aggressive cancer cell lines) and MSC (including tumor stroma-resident populations) has been demonstrated in a variety of cancers, the effects of local or systemic MSC delivery for regenerative purposes on persisting cancer cells during remission remain controversial. Both pro- and anti-tumorigenic effects of MSC have been reported in the literature. Our own data using breast cancer clinical isolates have suggested that dormant-like tumor-initiating cells do not respond to MSC signals, unlike actively dividing cancer cells which benefited from the presence of supportive MSC. The secretome of MSC isolated from various tissues may partially diverge, but it includes a core of cytokines (i.e. CCL2, CCL5, IL-6, TGFβ, VEGF), which have been implicated in tumor growth and/or metastasis. This article reviews published models for studying interactions between MSC and cancer cells with a focus

  2. Myofiber-specific TEAD1 overexpression drives satellite cell hyperplasia and counters pathological effects of dystrophin deficiency

    PubMed Central

    Southard, Sheryl; Kim, Ju-Ryoung; Low, SiewHui; Tsika, Richard W; Lepper, Christoph

    2016-01-01

    When unperturbed, somatic stem cells are poised to affect immediate tissue restoration upon trauma. Yet, little is known regarding the mechanistic basis controlling initial and homeostatic ‘scaling’ of stem cell pool sizes relative to their target tissues for effective regeneration. Here, we show that TEAD1-expressing skeletal muscle of transgenic mice features a dramatic hyperplasia of muscle stem cells (i.e. satellite cells, SCs) but surprisingly without affecting muscle tissue size. Super-numeral SCs attain a ‘normal’ quiescent state, accelerate regeneration, and maintain regenerative capacity over several injury-induced regeneration bouts. In dystrophic muscle, the TEAD1 transgene also ameliorated the pathology. We further demonstrate that hyperplastic SCs accumulate non-cell-autonomously via signal(s) from the TEAD1-expressing myofiber, suggesting that myofiber-specific TEAD1 overexpression activates a physiological signaling pathway(s) that determines initial and homeostatic SC pool size. We propose that TEAD1 and its downstream effectors are medically relevant targets for enhancing muscle regeneration and ameliorating muscle pathology. DOI: http://dx.doi.org/10.7554/eLife.15461.001 PMID:27725085

  3. Genome-wide expression profile of the response to spinal cord injury in Xenopus laevis reveals extensive differences between regenerative and non-regenerative stages

    PubMed Central

    2014-01-01

    Background Xenopus laevis has regenerative and non-regenerative stages. As a tadpole, it is fully capable of functional recovery after a spinal cord injury, while its juvenile form (froglet) loses this capability during metamorphosis. We envision that comparative studies between regenerative and non-regenerative stages in Xenopus could aid in understanding why spinal cord regeneration fails in human beings. Results To identify the mechanisms that allow the tadpole to regenerate and inhibit regeneration in the froglet, we obtained a transcriptome-wide profile of the response to spinal cord injury in Xenopus regenerative and non-regenerative stages. We found extensive transcriptome changes in regenerative tadpoles at 1 day after injury, while this was only observed by 6 days after injury in non-regenerative froglets. In addition, when comparing both stages, we found that they deployed a very different repertoire of transcripts, with more than 80% of them regulated in only one stage, including previously unannotated transcripts. This was supported by gene ontology enrichment analysis and validated by RT-qPCR, which showed that transcripts involved in metabolism, response to stress, cell cycle, development, immune response and inflammation, neurogenesis, and axonal regeneration were regulated differentially between regenerative and non-regenerative stages. Conclusions We identified differences in the timing of the transcriptional response and in the inventory of regulated transcripts and biological processes activated in response to spinal cord injury when comparing regenerative and non-regenerative stages. These genes and biological processes provide an entry point to understand why regeneration fails in mammals. Furthermore, our results introduce Xenopus laevis as a genetic model organism to study spinal cord regeneration. PMID:24885550

  4. Oral focal epithelial hyperplasia: report of three cases.

    PubMed

    Ghalayani, Parichehr; Tavakoli, Payam; Eftekhari, Mehdi; Haghighi, Mohammad Akhondzadeh

    2015-01-01

    Focal epithelial hyperplasia or Heck's disease is an infrequent asymptomatic condition caused by human papillomavirus types 13 or 32 affecting the mucous membrane of the mouth and is commonly seen in young individuals. Firstly, it was described in Indians and Eskimos, but it exists in various populations. We present three cases of Heck's disease in an Afghan immigrant family group living in Iran that seem to have familial predominance. The disease was identified as oral focal epithelial hyperplasia on the basis of histopathologic and clinical findings. The lesions were reduced significantly after 4 months of good oral hygiene. Dentists should be familiar with the clinical manifestations of these types of lesions that affect the oral cavity. In fact, histopathologic assessment and clinical observation are necessary to establish the diagnosis.

  5. Focal epithelial hyperplasia (Heck's disease) in two Chinese females.

    PubMed

    Liu, N; Li, Y; Zhou, Y; Zeng, X

    2012-08-01

    Focal epithelial hyperplasia, or Heck's disease, is a relatively rare virus-induced benign disease. To the best of the authors' knowledge it has not been reported in an ethnic Chinese population. The authors report two cases of focal epithelial hyperplasia (FEH) in Chinese patients, which were clinically and histologically in accord with FEH. In particular, the lesions in one case were located on the gingival mucosa, which is rarely affected by FEH. DNA extracted from paraffin-embedded specimens from the two patients was tested for the presence of human papilloma virus followed by specific polymerase chain reaction testing for 16, 18, 13, and 32 subtypes in order to confirm the clinical diagnosis.

  6. Focal nodular hyperplasia with major sinusoidal dilatation: a misleading entity

    PubMed Central

    Laumonier, Hervé; Frulio, Nora; Laurent, Christophe; Balabaud, Charles; Zucman-Rossi, Jessica; Bioulac-Sage, Paulette

    2010-01-01

    Focal nodular hyperplasia (FNH) is a benign liver lesion thought to be a non-specific response to locally increased blood flow. Although the diagnosis of FNH and hepatocellular adenoma (HCA) has made great progress over the last few years using modern imaging techniques, there are still in daily practice some difficulties concerning some atypical nodules. Here, the authors report the case of a 47-year-old woman with a single liver lesion thought to be, by imaging, an inflammatory HCA with major sinusoidal congestion. This nodule was revealed to be, at the microscopical level and after specific immunostaining and molecular analysis, an FNH with sinusoidal dilatation (so-called telangiectatic focal nodular hyperplasia). PMID:22798311

  7. [Laser tonsillectomy in tonsillar hyperplasia of early childhood].

    PubMed

    Helling, K; Abrams, J; Bertram, W K; Hohner, S; Scherer, H

    2002-05-01

    Tonsillotomy, the partial resection of hyperplastic tonsils, is generally rejected in Germany as a treatment option for obstructions of the isthmus faucium in early childhood. We think this approach merits consideration. The favorable results obtained with tonsillotomy in the University Hospital Benjamin Franklin (n = 637), a private clinic, and an ENT practice with surgical facilities (n = 189) showed that there is no justification for adhering to literature reports of severe late complications with scarred tonsillar crypts and peritonsillar abscesses. No patient has developed any of these complications thus far. Following tonsillotomy, preoperative complaints (snoring, respiratory obstruction, dysphagia, and failure to grow) decreased considerably. Thus, tonsillotomy proved to be a suitable modality for treating tonsillar hyperplasia in early childhood. The prerequisite for long-term success is strict limitation of this intervention to the diagnosis of tonsillar hyperplasia.

  8. Clinical outcomes of childhood x-irradiation for lymphoid hyperplasia

    SciTech Connect

    Pottern, L.M.

    1987-01-01

    A prospective study was conducted to explore the relationship between childhood x-irradiation for lymphoid hyperplasia and the subsequent development of thyroid gland and other head and neck disorders. All individuals under 18 years of age who were x-irradiated for lymphoid hyperplasia during the years 1938-69 at Children's Hospital Medical Center, Boston comprised the exposed population. The comparison group consisted of non-exposed, surgically treated individuals. The study included a health questionnaire and a clinical examination component. A history of thyroid cancer was reported by 11 exposed subjects and no non-exposed subjects. Significantly elevated standardized incidence ratios of thyroid cancer were seen for both exposed males and females, 19.9 and 12.1, respectively. The average thyroid radiation dose was 25.8 rads and the mean latency period was 17.3 years.

  9. Therapeutic options in the treatment of benign prostatic hyperplasia

    PubMed Central

    Sandhu, Jaspreet S

    2009-01-01

    Current theraputic options for the treatment of symptomatic benign prostatic hyperplasia (BPH) are reviewed. Therapeutic options for mild lower urinary tract symptoms (LUTS), as defined by the American Urological Association, are generally treated medically. Moderate to severe LUTS can be treated medically or with surgical therapy. Current medical and surgical treatments for LUTS secondary to BPH are reviewed and evolving treatments are explored. PMID:19936164

  10. Leydig cell hyperplasia in the setting of Klinefelter syndrome.

    PubMed

    Sterbis, Joseph; E-Nunu, Toritsetimiyin

    2015-07-24

    A man in his 20's with Klinefelter syndrome presented to the urology clinic with a recent history of left-sided orchalgia. Ultrasound evaluation demonstrated multiple small hypoechoic lesions bilaterally, with the largest lesion measured at 5 mm × 6 mm × 8 mm. Testis cancer tumour markers, chest radiographs and abdominal CT imaging were negative. A partial orchiectomy was performed on the largest lesion, demonstrating the presence of Leydig cell hyperplasia.

  11. Cell proliferation contributes to PNEC hyperplasia after acute airway injury.

    PubMed

    Stevens, T P; McBride, J T; Peake, J L; Pinkerton, K E; Stripp, B R

    1997-03-01

    Pulmonary neuroendocrine cells (PNECs) are airway epithelial cells that are capable of secreting a variety of neuropeptides. PNECs are scattered throughout the bronchial tree either as individual cells or clusters of cells termed neuroepithelial bodies (NEBs). PNECs and their secretory peptides have been considered to play a role in fetal lung development. Although the normal physiological function of PNECs and neuropeptides in normal adult lungs and in repair from lung injury is not known, PNEC hyperplasia has been associated with chronic lung diseases, such as bronchopulmonary dysplasia, and with chronic exposures, such as hypoxia, tobacco smoke, nitrosamines, and ozone. To evaluate changes in PNEC number and distribution after acute airway injury, FVB/n mice were treated with either naphthalene or vehicle. Naphthalene is an aromatic hydrocarbon that, at the dose used in this study, selectively destroys nonciliated bronchial epithelial cells (Clara cells) through cytochrome P-450-mediated metabolic activation into cytotoxic epoxides. PNECs were identified by immunohistochemical analysis of calcitonin gene-related peptide-like immunoreactivity (CGRP-IR). Proliferating cells were marked with [(3)H]thymidine incorporation. Acute naphthalene toxicity results in PNEC hyperplasia that is detectable after 5 days of recovery. PNEC hyperplasia is characterized by increased numbers of NEBs without significant changes in the number of isolated PNECs and by increased [(3)H]thymidine labeling of CGRP-IR cells. These data show that cell proliferation contributes to PNEC hyperplasia after acute airway injury and suggest that PNECs may be capable of more rapidly increasing their number in response to injury than previously recognized.

  12. Clinical and radiological findings of a bilateral coronoid hyperplasia case

    PubMed Central

    Torenek, Kubra; Duman, Suayip Burak; Bayrakdar, Ibrahim Sevki; Miloglu, Ozkan

    2015-01-01

    Coronoid hyperplasia (CH) is an infrequent condition that can be defined as an abnormal bony elongation of histologically normal bone. Progressive and painless difficulty in opening the mouth is the main clinical finding of CH. In this case report, the clinical and radiological findings for a 23-year-old male patient with bilateral CH are presented. When plain radiographies are not sufficient for diagnosis and evaluation of the CH, cone-beam computed tomography can be used. PMID:25713499

  13. Involvement of interleukin-21 in the epidermal hyperplasia of psoriasis.

    PubMed

    Caruso, Roberta; Botti, Elisabetta; Sarra, Massimiliano; Esposito, Maria; Stolfi, Carmine; Diluvio, Laura; Giustizieri, Maria Laura; Pacciani, Valentina; Mazzotta, Annamaria; Campione, Elena; Macdonald, Thomas T; Chimenti, Sergio; Pallone, Francesco; Costanzo, Antonio; Monteleone, Giovanni

    2009-09-01

    T cells are crucial mediators of the skin damage in psoriasis. We here show that interleukin-21 (IL-21), a T cell-derived cytokine, is highly expressed in the skin of individuals with psoriasis, stimulates human keratinocytes to proliferate and causes epidermal hyperplasia when injected intradermally into mice. In the human psoriasis xenograft mouse model, blockade of IL-21 activity resolves inflammation and reduces keratinocyte proliferation. Blocking IL-21 may represent a new therapeutic strategy in psoriasis.

  14. [Occult cancer in patients with symptomatic benign prostatic hyperplasia].

    PubMed

    Rodríguez Duarte, C; Aguillón, J; Rodríguez, H

    1991-05-01

    The results of a prospective study undertaken in 29 patients with symptomatic benign prostatic hyperplasia (BPH) are presented. Transrectal ultrasound, ultrasound-guided biopsy and prostate specific antigen (PSA) were utilized in the search for hidden cancer of the prostate. However, no cancer was detected in any patient. Very high values of PSA were found, particularly in patients with an indwelling catheter. Transrectal ultrasound yielded no false negatives and no complications were observed.

  15. Mandibular condylar hyperplasia: clinical, histopathological, and treatment considerations.

    PubMed

    Angiero, Francesca; Farronato, Giampietro; Benedicenti, Stefano; Vinci, Raffaele; Farronato, Davide; Magistro, Sarah; Stefani, Michele

    2009-01-01

    Condylar hyperplasia is a rare disorder characterized by an increased volume of the condyle, ramus, and mandibular body leading to facial asymmetry. We present three cases of condylar hyperplasia: two women and one man, age range 27 to 34. Clinically, all three patients showed a deviation of the mandible to the opposite side and a protruded position of the chin, hypertrophy of the lower border of the mandible, combined with an elongation of the mandibular ramus, open-bite on the deformed side, and cross-bite on the opposite side. In all three cases, scintigraphy showed an increased uptake. Radiography and CT scanning confirmed the clinical diagnosis and patients were subjected to surgery, comprising high condylectomy on the affected side with access in the pre-tragus area. The surgical piece sent to the Institute of Pathological Anatomy for histological examination revealed a nonuniform picture, in terms of both the depth of cartilage islands and the thickness of the fibrous layer covering the joint surface. Common to all three cases, however, was the apparent evolution of fibrous tissue to cartilage, and of this to compact bone tissue. At two-four years, all cases have maintained a good occlusal response. The asymmetric deformity of the mandible resulting from the rare condition of hemimandibular hyperplasia is presented and the clinical, histopathological and therapeutic aspects discussed.

  16. Pseudoepitheliomatous hyperplasia after diode laser oral surgery. An experimental study

    PubMed Central

    Seoane, Juan; González-Mosquera, Antonio; García-Martín, José-Manuel; García-Caballero, Lucía; Varela-Centelles, Pablo

    2015-01-01

    Background To examine the process of epithelial reparation in a surgical wound caused by diode laser. Material and Methods An experimental study with 27 Sprage-Dawley rats was undertaken. The animals were randomly allocated to two experimental groups, whose individuals underwent glossectomy by means of a diode laser at different wattages, and a control group treated using a number 15 scalpel blade. The animals were slaughtered at the 2nd, 7th, and 14th day after glossectomy. The specimens were independently studied by two pathologists (blinded for the specimens’ group). Results At the 7th day, re-epithelisation was slightly faster for the control group (conventional scalpel) (p=0.011). At the 14th day, complete re-epithelization was observed for all groups. The experimental groups displayed a pseudoepitheliomatous hyperplasia. Conclusions It is concluded that, considering the limitations of this kind of experimental studies, early re-epithelisation occurs slightly faster when a conventional scalpel is used for incision, although re-epithelisation is completed in two weeks no matter the instrument used. In addition, pseudoepitheliomatous hyperplasia is a potential event after oral mucosa surgery with diode laser. Knowledge about this phenomenon (not previously described) may prevent diagnostic mistakes and inadequate treatment approaches, particularly when dealing with potentially malignant oral lesions. Key words:Diode laser, animal model, oral biopsy, oral cancer, oral precancer, pseudoepitheliomatous hyperplasia. PMID:26116841

  17. Adipocyte hyperplasia and RMI1 in the treatment of obesity.

    PubMed

    Suwa, Akira; Kurama, Takeshi; Shimokawa, Teruhiko

    2011-02-01

    The escalating prevalence of obesity is one of the most pressing health concerns of the modern era, yet existing medicines to combat this global pandemic are disappointingly limited in terms of safety and effectiveness. The inadequacy of currently available therapies for obesity has made new drug development crucial. In the past several decades, however, major progress has been achieved in understanding adipocyte hyperplasia associated with the pathogenesis of obesity, and consequently new potential targets for the medical treatment of obesity have been identified. We primarily review recent progress in the regulation of adipocyte hyperplasia as a novel emerging nontraditional approach. In this minireview, we focus on recQ-mediated genome instability 1 (RMI1), a recently identified novel molecular target for obesity treatment. RMI1-deficient mice have been found to be resistant to high-fat diet- and genetics-related obesity. Expression of this protein is regulated by E2F transcription factors, and recent studies have suggested that RMI1 plays an important role in the control of energy homeostasis during the development of obesity, with a mode of action based on the regulation of adipocyte hyperplasia.

  18. Phytotherapeutic Agents for Benign Prostatic Hyperplasia: An Overview.

    PubMed

    Passi, Neelima Dhingra

    2016-06-20

    Benign prostatic hyperplasia (BPH) the most common condition in aging men is the non malignant enlargement of the prostate gland with increase in numbers of both epithelial and stromal cells within the periurethal transition zone of the prostate. Sources of symptoms in patient with BPH appear to be both static and dynamic component. Management of BPH has undergone a rapid evolution over the past decade to aid men with lower urinary tract symptoms attributed to bladder outlet obstruction. Treatment of clinical BPH aims to improve symptoms, prevent urinary tract infections, avoid renal insult, relief obstruction and improve bladder emptying.Prostate cancer patients and those with benign prostatic hyperplasia are increasingly exploring the use of plant derived non-nutritive compounds with protective or disease preventive properties, especially due to long term side effects of pharmacological treatment and risk of mortality associated with surgical procedures. Phytotherapeutic preparations are plant extracts with different components obtained by different extraction procedures. Numerous mechanisms of action have been postulated for mono and combination plant extracts. This article give a brief account of rationale and efficacy of various existing phytotherapeutic agents in the management of benign prostatic hyperplasia, including the herbs which hold the potential promise are also mentioned , although much research is still required.

  19. Protection against fat cell hyperplasia in a hibernator, Glis glis.

    PubMed

    Mrosovsky, N; Nash, P; Faust, I M

    1987-10-01

    Dormice, Glis glis, were fed a high-fat diet for 11 mo in one experiment: in another experiment they were fed a high-fat diet for 5 mo, either at room temperature (21.5 degrees C) or in a warm room (27 degrees C). Only in the latter group did adipocyte hyperplasia occur; this was significant in all the fat depots studied (inguinal, retroperitoneal, and gonadal). In the other groups there was no evidence of fat cell hyperplasia, despite weight gains from approximately 160 g (peaks on chow diet) to approximately 250 g (maximums on high-fat diet). Instead, fat cell size, assessed from biopsies of the inguinal area, became considerably enlarged. Taken together with earlier data from other species, the results suggest that hibernators are protected against fat cell hyperplasia. In dormice this protection appears to be present at all phases of their seasonal weight cycles. For species that experience several cycles of weight gain and loss in their lives, it may be adaptive to avoid increases in adipocyte number.

  20. Hot spot liver scan in focal nodular hyperplasia

    SciTech Connect

    Piers, D.A.; Houthoff, H.J.; Krom, R.A.F.; Schuur, K.H.; Sikkens, H.; Weits, J.

    1980-12-01

    In scintigraphy of the liver with radiocolloid, space-occupying lesions generally are visualized as regions of decreased accumulation of radioactivity. Rarely focal areas of increased activity are depicted; most are related to altered vascular dynamics in the liver secondary to obstruction of the superior or inferior vena cava or the hepatic veins. There are reports of single cases of focally increased activity due to a hepatic hemangioma, hepatic venoocclusive disease, herniation of a part of the liver, and a liver hot spot found after radiocolloid injection via a malpositioned central venous catheter in one of the hepatic vein branches. In patients with focal nodular hyperplasia, liver scans with solitary defects as well as normal patterns are found. In some cases, increased uptake of colloid in the lesion has been documented. Pasquier and Dorta reported a patient with a palpable mass in the left liver lobe with increased accumulation of radioactivity on the radiocolloid liver scan. The histologic diagnosis was hamartoma, but reviewing the description and considering the confusion in the past concerning the nomenclature, this case is suggestive of focal nodular hyperplasia. We report a patient with focal nodular hyperplasia who had increased radiocolloid uptake in the lesion. The radionuclide studies are compared with angiography, sonography, and computed tomography. An explanation for the localized increased colloid accumulation based on histologic findings is suggested.

  1. Insurance systems and reimbursement concerning research and development of regenerative medicine in Japan.

    PubMed

    Okada, Kiyoshi; Miyata, Toshio; Sawa, Yoshiki

    2017-03-01

    In Japan, the Act on the Safety of Regenerative Medicine and the Pharmaceuticals, Medical Devices and Other Therapeutic Products Act were enacted in November 2014, creating a new framework for clinical research and products related to regenerative medicine. Together with these regulatory frameworks, new insurance procedures were created for handling regenerative medicine in Japan. For developing regenerative medicine in Japan, understanding medical insurance greatly influences funding and venture success, particularly in the stages between clinical research and market launch. The study aimed to identify the issues and examples surrounding Japan's present medical insurance system, especially for regenerative medicine. We believe that building stronger insurance systems for regenerative medicine is essential for internationally aligning and harmonizing the progress of regenerative medicine.

  2. Nanotechnologies and regenerative medical approaches for space and terrestrial medicine.

    PubMed

    Grattoni, Alessandro; Tasciotti, Ennio; Fine, Daniel; Fernandez-Moure, Joseph S; Sakamoto, Jason; Hu, Ye; Weiner, Bradley; Ferrari, Mauro; Parazynski, Scott

    2012-11-01

    One purpose of the International Space Station (ISS) is to explore powerful new areas of biomedical science in microgravity. Recent advances in nanotechnology applied to medicine--what we now refer to as nano-medicine--and regenerative medicine have enormous untapped potential for future space and terrestrial medical applications. Novel means for drug delivery and nanoscale screening tools will one day benefit astronauts venturing to Mars and places beyond, while the space laboratory will foster advances in nanotechnologies for diagnostic and therapeutic tools to help our patients here on Earth. Herein we review a series of nanotechnologies and selected regenerative medical approaches and highlight key areas of ongoing and future investigation that will benefit both space and terrestrial medicine. These studies target significant areas of human disease such as osteoporosis, diabetes, radiation injury, and many others.

  3. Investigation of electroforming techniques. [fabrication of regeneratively cooled thrust chambers

    NASA Technical Reports Server (NTRS)

    Malone, G. A.

    1975-01-01

    Copper and nickel electroforming was examined for the purpose of establishing the necessary processes and procedures for repeatable, successful fabrication of the outer structures of regeneratively cooled thrust chambers. The selection of electrolytes for copper and nickel deposition is described. The development studies performed to refine and complete the processes necessary for successful chamber shell fabrication and the testing employed to verify the applicability of the processes and procedures to small scale hardware are described. Specifications were developed to afford a guideline for the electroforming of high quality outer shells on regeneratively cooled thrust chamber liners. Test results indicated repeatable mechanical properties could be produced in copper deposits from the copper sulfate electrolyte with periodic current reversal and in nickel deposits from the sulfamate solution. Use of inert, removable channel fillers and the conductivizing of such is described. Techniques (verified by test) which produce high integrity bonds to copper and copper alloy liners are discussed.

  4. High-precision buffer circuit for suppression of regenerative oscillation

    NASA Technical Reports Server (NTRS)

    Tripp, John S.; Hare, David A.; Tcheng, Ping

    1995-01-01

    Precision analog signal conditioning electronics have been developed for wind tunnel model attitude inertial sensors. This application requires low-noise, stable, microvolt-level DC performance and a high-precision buffered output. Capacitive loading of the operational amplifier output stages due to the wind tunnel analog signal distribution facilities caused regenerative oscillation and consequent rectification bias errors. Oscillation suppression techniques commonly used in audio applications were inadequate to maintain the performance requirements for the measurement of attitude for wind tunnel models. Feedback control theory is applied to develop a suppression technique based on a known compensation (snubber) circuit, which provides superior oscillation suppression with high output isolation and preserves the low-noise low-offset performance of the signal conditioning electronics. A practical design technique is developed to select the parameters for the compensation circuit to suppress regenerative oscillation occurring when typical shielded cable loads are driven.

  5. Trends in the stem cell and regenerative medicine industry.

    PubMed

    Ilic, Dusko

    2012-09-01

    The World Stem Cell Regenerative Medicine Congress series, now in its 7th year, is organized annually in the USA, Europe and Asia by Terrapinn, a business media company with its head office in London, and has grown over the last several years into the largest and probably the most important strategic stem cell conference where regulators, investors, big pharma, and small and medium enterprises gather to share and create synergy in developing and commercializing stem cell applications. The conference, held in London on 21-23 May 2012, only confirmed that this series is the meeting to attend if you want to get a clear understanding of trends in the stem cell and regenerative medicine industry.

  6. The Impact of Biomechanics in Tissue Engineering and Regenerative Medicine

    PubMed Central

    Butler, David L.; Goldstein, Steven A.; Guo, X. Edward; Kamm, Roger; Laurencin, Cato T.; McIntire, Larry V.; Mow, Van C.; Nerem, Robert M.; Sah, Robert L.; Soslowsky, Louis J.; Spilker, Robert L.; Tranquillo, Robert T.

    2009-01-01

    Biomechanical factors profoundly influence the processes of tissue growth, development, maintenance, degeneration, and repair. Regenerative strategies to restore damaged or diseased tissues in vivo and create living tissue replacements in vitro have recently begun to harness advances in understanding of how cells and tissues sense and adapt to their mechanical environment. It is clear that biomechanical considerations will be fundamental to the successful development of clinical therapies based on principles of tissue engineering and regenerative medicine for a broad range of musculoskeletal, cardiovascular, craniofacial, skin, urinary, and neural tissues. Biomechanical stimuli may in fact hold the key to producing regenerated tissues with high strength and endurance. However, many challenges remain, particularly for tissues that function within complex and demanding mechanical environments in vivo. This paper reviews the present role and potential impact of experimental and computational biomechanics in engineering functional tissues using several illustrative examples of past successes and future grand challenges. PMID:19583462

  7. The theory of an active magnetic regenerative refrigerator

    NASA Technical Reports Server (NTRS)

    Barclay, J. A.

    1983-01-01

    The adiabatic temperature change with field which is limited to about 2 K/Tesla for ferromagnets near their Curie temperatures by the change of magnetization with temperature and the lattice heat capacity is discussed. Practical magnetic refrigerators operate on a regenerative cycle such as the Brayton cycle. This cycle can be executed through the use of an active magnetic regenerator, i.e., a regenerator composed of magnetic material that is cycled in an out of a magnetic field with appropriate fluid flows. The theory of these devices is predicted by solving the partial differential equations that describe fluid and the magnetic solid. The active magnetic regenerator is described along with the method of calculation. Temperature profiles for a normal regenerator and a magnetic regenerative refrigerator are shown.

  8. Regenerative Environmental Control and Life Support System Diagram

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This diagram shows the flow of recyclable resources in the International Space Station (ISS). The Environmental Control and Life Support System (ECLSS) Group of the Flight Projects Directorate at the Marshall Space Flight Center is responsible for the regenerative ECLSS hardware, as well as providing technical support for the rest of the system. The regenerative ECLSS, whose main components are the Water Recovery System (WRS), and the Oxygen Generation System (OGS), reclaims and recycles water and oxygen. The ECLSS maintains a pressurized habitation environment, provides water recovery and storage, maintains and provides fire detection / suppression, and provides breathable air and a comfortable atmosphere in which to live and work within the ISS. The ECLSS hardware will be located in the Node 3 module of the ISS.

  9. Spacecraft Radiator Freeze Protection Using a Regenerative Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Ungar, Eugene K.; Schunk, Richard G.

    2011-01-01

    An active thermal control system architecture has been modified to include a regenerative heat exchanger (regenerator) inboard of the radiator. Rather than using a radiator bypass valve a regenerative heat exchanger is placed inboard of the radiators. A regenerator cold side bypass valve is used to set the return temperature. During operation, the regenerator bypass flow is varied, mixing cold radiator return fluid and warm regenerator outlet fluid to maintain the system setpoint. At the lowest heat load for stable operation, the bypass flow is closed off, sending all of the flow through the regenerator. This lowers the radiator inlet temperature well below the system set-point while maintaining full flow through the radiators. By using a regenerator bypass flow control to maintain system setpoint, the required minimum heat load to avoid radiator freezing can be reduced by more than half compared to a radiator bypass system.

  10. Modelling the regenerative niche: a major challenge in biomaterials research†

    PubMed Central

    Kirkpatrick, C. James

    2015-01-01

    By definition, biomaterials are developed for clinical application. In the field of regenerative medicine their principal function is to play a significant, and, if possible, an instructive role in tissue healing. In the last analysis the latter involves targeting the ‘regenerative niche’. The present paper will address the problem of simulating this niche in the laboratory and adopts a life science approach involving the harnessing of heterotypic cellular communication to achieve this, that is, the ability of cells of different types to mutually influence cellular functions. Thus, co-culture systems using human cells are the methodological focus and will concern four exemplary fields of regeneration, namely, bone, soft tissue, lower respiratory tract and airway regeneration. The working hypothesis underlying this approach is that in vitro models of higher complexity will be more clinically relevant than simple monolayer cultures of transformed cell lines in testing innovative strategies with biomaterials for regeneration. PMID:26816650

  11. Regenerative medicine using dental pulp stem cells for liver diseases

    PubMed Central

    Ohkoshi, Shogo; Hara, Hajime; Hirono, Haruka; Watanabe, Kazuhiko; Hasegawa, Katsuhiko

    2017-01-01

    Acute liver failure is a refractory disease and its prognosis, if not treated using liver transplantation, is extremely poor. It is a good candidate for regenerative medicine, where stem cell-based therapies play a central role. Mesenchymal stem cells (MSCs) are known to differentiate into multiple cell lineages including hepatocytes. Autologous cell transplant without any foreign gene induction is feasible using MSCs, thereby avoiding possible risks of tumorigenesis and immune rejection. Dental pulp also contains an MSC population that differentiates into hepatocytes. A point worthy of special mention is that dental pulp can be obtained from deciduous teeth during childhood and can be subsequently harvested when necessary after deposition in a tooth bank. MSCs have not only a regenerative capacity but also act in an anti-inflammatory manner via paracrine mechanisms. Promising efficacies and difficulties with the use of MSC derived from teeth are summarized in this review. PMID:28217369

  12. Cell sheet approach for tissue engineering and regenerative medicine.

    PubMed

    Matsuura, Katsuhisa; Utoh, Rie; Nagase, Kenichi; Okano, Teruo

    2014-09-28

    After the biotech medicine era, regenerative medicine is expected to be an advanced medicine that is capable of curing patients with difficult-to-treat diseases and physically impaired function. Our original scaffold-free cell sheet-based tissue engineering technology enables transplanted cells to be engrafted for a long time, while fully maintaining their viability. This technology has already been applied to various diseases in the clinical setting, including the cornea, esophagus, heart, periodontal ligament, and cartilage using autologous cells. Transplanted cell sheets not only replace the injured tissue and compensate for impaired function, but also deliver growth factors and cytokines in a spatiotemporal manner over a prolonged period, which leads to promotion of tissue repair. Moreover, the integration of stem cell biology and cell sheet technology with sufficient vascularization opens possibilities for fabrication of human three-dimensional vascularized dense and intact tissue grafts for regenerative medicine to parenchymal organs.

  13. Regenerative Fuel Cell Test Rig at Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Chang, Bei-Jiann; Johnson, Donald W.; Garcia, Christopher P.; Jakupca, Ian J.; Scullin, Vincent J.; Bents, David J.

    2003-01-01

    The regenerative fuel cell development effort at Glenn Research Center (GRC) involves the integration of a dedicated fuel cell and electrolyzer into an energy storage system test rig. The test rig consists of a fuel cell stack, an electrolysis stack, cooling pumps, a water transfer pump, gas recirculation pumps, phase separators, storage tanks for oxygen (O2) and hydrogen (H2), heat exchangers, isolation valves, pressure regulators, interconnecting tubing, nitrogen purge provisions, and instrumentation for control and monitoring purposes. The regenerative fuel cell (RFC) thus formed is a completely closed system which is capable of autonomous cyclic operation. The test rig provides direct current (DC) load and DC power supply to simulate power consumption and solar power input. In addition, chillers are used as the heat sink to dissipate the waste heat from the electrochemical stack operation. Various vents and nitrogen (N2) sources are included in case inert purging is necessary to safe the RFC test rig.

  14. Differentiation of pluripotent stem cells for regenerative medicine.

    PubMed

    Li, Ke; Kong, Yan; Zhang, Mingliang; Xie, Fei; Liu, Peng; Xu, Shaohua

    2016-02-26

    A long-standing goal in regenerative medicine is to obtain scalable functional cells on demand to replenish cells lost in various conditions, including relevant diseases, injuries, and aging. As an unlimited cell source, pluripotent stem cells (PSCs) are invaluable for regenerative medicine, because they have the potential to give rise to any cell type in an organism. For therapeutic purposes, it is important to develop specific approach to directing PSC differentiation towards desired cell types efficiently. Through directed differentiation, PSCs could give rise to scalable, clinically relevant cells for in vivo transplantation, as well as for studying diseases in vitro and discovering drugs to treat them. Over the past few years, significant progress has been made in directing differentiation of PSCs into a variety of cell types. In this review, we discuss recent progress in directed differentiation of PSCs, clinical translation of PSC-based cell replacement therapies, and remaining challenges.

  15. Stem cells: a promising source for vascular regenerative medicine.

    PubMed

    Rammal, Hassan; Harmouch, Chaza; Lataillade, Jean-Jacques; Laurent-Maquin, Dominique; Labrude, Pierre; Menu, Patrick; Kerdjoudj, Halima

    2014-12-15

    The rising and diversity of many human vascular diseases pose urgent needs for the development of novel therapeutics. Stem cell therapy represents a challenge in the medicine of the twenty-first century, an area where tissue engineering and regenerative medicine gather to provide promising treatments for a wide variety of diseases. Indeed, with their extensive regeneration potential and functional multilineage differentiation capacity, stem cells are now highlighted as promising cell sources for regenerative medicine. Their multilineage differentiation involves environmental factors such as biochemical, extracellular matrix coating, oxygen tension, and mechanical forces. In this review, we will focus on human stem cell sources and their applications in vascular regeneration. We will also discuss the different strategies used for their differentiation into both mature and functional smooth muscle and endothelial cells.

  16. Derivation and application of pluripotent stem cells for regenerative medicine.

    PubMed

    Wang, Jiaqiang; Zhou, Qi

    2016-06-01

    Pluripotent stem cells (PSCs) are cells that can differentiate into any type of cells in the body, therefore have valuable promise in regenerative medicine of cell replacement therapies and tissue/organ engineering. PSCs can be derived either from early embryos or directly from somatic cells by epigenetic reprogramming that result in customized cells from patients. Here we summarize the methods of deriving PSCs, the various types of PSCs generated with different status, and their versatile applications in both clinical and embryonic development studies. We also discuss an intriguing potential application of PSCs in constructing tissues/organs in large animals by interspecies chimerism. All these emerging findings are likely to contribute to the breakthroughs in biological research and the prosperous prospects of regenerative medicine.

  17. Regenerative thermal oxidation and alternative technologies for VOC control

    SciTech Connect

    Biedell, E.L.

    1995-12-31

    Thermal oxidation technologies have been used successfully to control VOC`s for many years but the recent 1990 Clean Air Act Amendments have spurred improvements in the established processes and development of economic alternatives. The combination of the regulatory maze and confusion in the selection of the best technology for a particular application has created a potential nightmare for those companies facing a need to reduce their VOC EMISSIONS. The relative advantages and disadvantages of regenerative, recuperative and catalytic oxidizers will be reviewed, with an emphasis on the economic justification for regenerative thermal oxidation (RTO). Control efficiencies of more than 99% have been demonstrated for RTO`s on a multitude of industrial process exhaust streams. Lowest evaluated cost over a fifteen to twenty year effective equipment life is a key selection criteria. This paper describes the underlying principles of thermal oxidation, and discusses the applicability of these and other emerging technologies for VOC control.

  18. Antarctic analogs as a testbed for regenerative life support technologies

    NASA Technical Reports Server (NTRS)

    Roberts, D. R.; Andersen, D. T.; Mckay, C. P.; Wharton, R. A., Jr.; Rummel, J. D.

    1991-01-01

    The feasibility of using Antarctica as a platform for creating earth-based simulations of regenerative life support systems (LSSs) for future space missions is discussed. The requirements for a bioregenerative LSS and the types of technologies that may be used in such a system are examined. Special attention is given to the objectives and the organization of the NASA's CELSS program for the development of regenerative LSSs to support long-duration human missions in space, largely independent of resupply, in a safe and reliable manner. There are two types of locations on the continent of Antarctica suitable for the placement of simulation facilities: the polar plateau and the ice-free dry valleys. The unique attributes that lend each type of location to very different functions as simulation facilities are discussed.

  19. Regenerative medicine for the kidney: stem cell prospects & challenges

    PubMed Central

    2013-01-01

    The kidney has key roles in maintaining human health. There is an escalating medical crisis in nephrology as growing numbers of patients suffer from kidney diseases that culminate in organ failure. While dialysis and transplantation provide life-saving treatments, these therapies are rife with limitations and place significant burdens on patients and healthcare systems. It has become imperative to find alternative ways to treat existing kidney conditions and preemptive means to stave off renal dysfunction. The creation of innovative medical approaches that utilize stem cells has received growing research attention. In this review, we discuss the regenerative and maladaptive cellular responses that occur during acute and chronic kidney disease, the emerging evidence about renal stem cells, and some of the issues that lie ahead in bridging the gap between basic stem cell biology and regenerative medicine for the kidney. PMID:23688352

  20. Does Preoperative Diagnosis of Endometrial Hyperplasia Necessitate Intraoperative Frozen Section Consultation?

    PubMed Central

    Boyraz, Gokhan; Başaran, Derman; Salman, Mehmet C.; Özgül, Nejat; Yüce, Kunter

    2016-01-01

    Background In women with endometrial hyperplasia, there is a risk for co-existent endometrial cancer when patients are subjected to immediate surgical treatment. Aims The aim of this study was to investigate the frequency of endometrial cancer and the accuracy of frozen section analysis at the time of hysterectomy among patients with endometrial hyperplasia, to reveal whether or not a preoperative diagnosis of endometrial hyperplasia necessitates frozen section consultation. Study Design Retrospective cross-sectional study. Methods A department database review was performed to identify patients who were subjected to hysterectomy with a preoperative diagnosis of endometrial hyperplasia, during the period from 2007 to 2014. Results The study group included 189 cases. The final pathological examination revealed endometrial cancer in 16 women (8.4%). The risk of cancer in patients with endometrial hyperplasia was 1 of 125 (0.8%) in simple hyperplasia without atypia, 1 of 21 (4.8%) in complex hyperplasia without atypia and 14 of 43 (32.5%) in atypical hyperplasia. Of women with cancer, 2 of 16 (12.5%) had high-risk features. Frozen section analysis was requested in 46 cases. Frozen sections helped to identify six out of 11 cases of endometrial cancer (54.5%). The sensitivity, specificity and positive and negative predictive values of frozen section analysis for the detection of endometrial cancer among women with endometrial hyperplasia were 54.4%, 97.2%, 85.7% and 87.5%, respectively. Conclusion Although a significant proportion of patients with atypical endometrial hyperplasia are diagnosed with endometrial cancer following hysterectomy, most of these cases have low-risk features and do not require surgical staging. Additionally, intraoperative frozen section analysis if not helpful for diagnosing concurrent endometrial cancer in patients with endometrial hyperplasia. Therefore, it seems that patients with endometrial hyperplasia can be operated upon in settings with

  1. On the Genealogy of Tissue Engineering and Regenerative Medicine

    PubMed Central

    2015-01-01

    In this article, we identify and discuss a timeline of historical events and scientific breakthroughs that shaped the principles of tissue engineering and regenerative medicine (TERM). We explore the origins of TERM concepts in myths, their application in the ancient era, their resurgence during Enlightenment, and, finally, their systematic codification into an emerging scientific and technological framework in recent past. The development of computational/mathematical approaches in TERM is also briefly discussed. PMID:25343302

  2. SULFUR DIOXIDE - SULFUR TRIOXIDE REGENERATIVE FUEL CELL RESEARCH

    DTIC Science & Technology

    The thermodynamics and electrolytic characteristics are discussed of an SO2-SO3 regenerative, closed-cycle fuel cell , and summarizes the electrolytic...electrochemical, and phase separation research conducted during a study program to determine the practicability of such a fuel cell . The...experimental results obtained were at such wide variance with the theoretical concept that it became apparent that a fuel cell of this type is not feasible. (Author)

  3. Carbon nanotube torsional springs for regenerative braking systems

    NASA Astrophysics Data System (ADS)

    Liu, Sanwei; Martin, Corbin; Lashmore, David; Schauer, Mark; Livermore, Carol

    2015-10-01

    The modeling and demonstration of large stroke, high energy density and high power density torsional springs based on carbon nanotube (CNT) yarns is reported, as well as their application as energy-storing actuators for regenerative braking systems. An originally untwisted CNT yarn is cyclically loaded and unloaded in torsion, with the maximum rotation angle increasing incrementally until failure. The measured average extractable energy density values are 2.9 kJ kg-1  ±  1.2 kJ kg-1 and 3.4 kJ kg-1  ±  0.4 kJ kg-1 for 1-ply CNT yarns and 2-ply CNT yarns, respectively. Additionally, a regenerative braking system is demonstrated to capture the kinetic energy of a wheel and store it as elastic energy in twisted CNT yarns. When the yarn’s twist is released, the stored energy reaccelerates the wheel. The measured energy and mean power densities of the CNT yarns in the simple regenerative braking setup are on average 3.3 kJ kg-1 and 0.67 kW kg-1, respectively, with maximum measured values of up to 4.7 kJ kg-1 and 1.2 kW kg-1, respectively. A slightly lower energy density of up to 1.2 kJ kg-1 and a 0.29 kW kg-1 mean power density are measured for CNT yarns in a more complex setup that mimics a unidirectional rotating regenerative braking mechanism.

  4. The Almost Regenerative Method for Stochastic System Simulations

    DTIC Science & Technology

    1975-12-01

    Wolfowitz rank product-moment test for lag 1 [ Wald and Wolfowitz (1943)]. The central idea is to replace the X ’s in (A.3) by their ranks, where the...of spurious observations. Wald and Wolfowitz showed that the resulting rank product-moment statistic, r , is asymptotically normally...Chapter 4: Using the Almost Regenerative Method to Obtain Order of Magnitude Improvements in MSE Efficiency .... 49 4.1 The M/M/c Tandem Queue

  5. Preventing Vision Loss from Blast Injuries with Regenerative Biomaterial

    DTIC Science & Technology

    2013-08-01

    addition, eye injury is the number one cause of field evacuation in the military. Corneal wounds cause intense pain and may lead to blindness...depending on the severity of injury. Seryx’s regenerative biomaterial accelerates corneal healing and soothes the damaged surface by providing a coating...immortalized human corneal -limbal epithelial (HCLE) cell line. HCLE cells were grown to confluence in culture, and the media was then supplemented

  6. Regen compressors power Capo Bon trans-med station

    SciTech Connect

    de Biasi, V.

    1981-11-01

    It is expected that Algeria will begin deliveries of natural gas from the Hassi-R'Mel gasfield in the Sahara Desert to Italy by the end of 1981 or early 1982. The main station for the Trans-Med natural gas pipeline, powered by five regenerative M5322R gas turbines, has a design throughput of some 1.6 million m/sup 3//hr and serves as the boost station for the submarine section of the pipeline.

  7. A graphite-lined regeneratively cooled thrust chamber

    NASA Technical Reports Server (NTRS)

    Stubbs, V. R.

    1972-01-01

    Design concepts, based on use of graphite as a thermal barrier for regeneratively cooled FLOX-methane thrust chambers, have been screened and concepts selected for detailed thermodynamic, stress, and fabrication analyses. A single design employing AGCarb-101, a fibrous graphite composite material, for a thermal barrier liner and an electroformed nickel structure with integral coolant passages was selected for fabrication and testing. The fabrication processes and the test results are described and illustrated.

  8. Potential Therapeutic Strategies of Regenerative Medicine for Renal Failure.

    PubMed

    Mata-Miranda, Monica Maribel; Delgado-Macuil, Raul Jacobo; Rojas-Lopez, Marlon; Martinez-Flores, Ricardo; Vazquez-Zapien, Gustavo Jesus

    2017-03-17

    Kidney diseases are a public health problem worldwide; the mortality rate is between 50 and 80%. Available therapies include replacement function by dialysis or transplant, associated with a high morbidity and mortality; kidney transplantation is limited by the shortage of donor organs, immune rejection and lifelong treatment with immunosuppressive. Likewise, none of these treatments compensates all kidney functions. There is a great concern in developing more effective therapies with the ability to replace the wide range of renal functions, so that, new researches on developing therapeutic strategies have focused on regenerative medicine, science that includes artificial creation of tissues and organs, in order to repair or replace a tissue or organ function. The aim of this paper is to review the new advances in regenerative medicine strategies for treatment of renal failure. Generally, regenerative medicine comprises two therapeutic strategies: cell therapy and tissue engineering. Cell therapy techniques depend on cell and tissue culture, with the aim to grow specific cells that will replace morphological structures, tissues and functions. In this area, some investigations that include the use of stem cells have been carried out. Tissue engineering complements cell therapy combining techniques of biological sciences and engineering to create structures and devices as scaffolds, matrices or biocompatible materials, which alone or in combination will give support and facilitate the repair of damaged tissue. Even though there is a great advance in regenerative medicine strategies, we are far from using any of its techniques on health institutions, due to it is necessary to evaluate side effects, biodistribution, dosage, type of administration, vehicle of cell therapy, as well as the evaluation of response time and long-term studies, among other studies.

  9. Hydrogen-Oxygen PEM Regenerative Fuel Cell Energy Storage System

    NASA Technical Reports Server (NTRS)

    Bents, David J.; Scullin, Vincent J.; Chang, Bei-Jiann; Johnson, Donald W.; Garcia, Christopher P.

    2005-01-01

    An introduction to the closed cycle hydrogen-oxygen polymer electrolyte membrane (PEM) regenerative fuel cell (RFC), recently constructed at NASA Glenn Research Center, is presented. Illustrated with explanatory graphics and figures, this report outlines the engineering motivations for the RFC as a solar energy storage device, the system requirements, layout and hardware detail of the RFC unit at NASA Glenn, the construction history, and test experience accumulated to date with this unit.

  10. Regenerative amplification in alexandrite of pulses from specialized oscillators

    SciTech Connect

    Bado, P.; Pessot, M.; Squier, J.; Mourou, G.A.; Harter, D.J.

    1988-06-01

    The authors describe an alexandrite regenerative amplifier used to amplify the output of various specialized oscillators. Nanosecond pulses from a narrow frequency CW-pumped dye laser, picosecond pulses from a gain-switched diode laser, and femtosecond pulses from a synchronously pumped dye laser were amplified by six-ten orders of magnitude in a single stage while conserving the temporal and spectral profiles characteristic to the oscillators.

  11. Design of a regenerative fuel cell system for Space Station

    NASA Technical Reports Server (NTRS)

    Hoberecht, M. A.; Rieker, L. L.

    1985-01-01

    The NASA Space Station will employ alkaline regenerative fuel cells (RFCs) as its sole electrochemical energy storage system, in virtue of demonstrated technology readiness and a high degree of system-level design flexibility. NASA Johnson and NASA Lewis are currently engaged in the development of a 10-kW alkaline engineering model system, for 1987 delivery, which will encompass a fully autonomous 120-V system with 55 percent overall electrical efficiency and a 20,000-hr service life.

  12. Status of the Regenerative ECLSS Water Recovery System

    NASA Technical Reports Server (NTRS)

    Carter, Donald Layne

    2009-01-01

    NASA has completed the delivery of the regenerative Water Recovery System (WRS) for the International Space Station (ISS). The major assemblies included in this system are the Water Processor Assembly (WPA) and Urine Processor Assembly (UPA). This paper summarizes the final effort to deliver the hardware to the Kennedy Space Center for launch on STS-126, the on-orbit status as of April 2009, and describes some of the technical challenges encountered and lessons learned over the past year.

  13. The Application of Microwave Incineration to Regenerative Life Support

    NASA Technical Reports Server (NTRS)

    Sun, Sidney C.; Srinivasan, Venkatesh; Covington, Al (Technical Monitor)

    1995-01-01

    Future human exploration missions will require life support systems that are highly regenerative, requiring minimum resupply, enabling the crews to be largely self-sufficient. Solid wastes generated in space will be processed to recover usable material. Researchers at NASA Ames Research Center are studying a commercially-produced microwave incinerator as a solid waste processor. This paper will describe the results of testing to-date.

  14. Leptin effects on the regenerative capacity of human periodontal cells.

    PubMed

    Nokhbehsaim, Marjan; Keser, Sema; Nogueira, Andressa Vilas Boas; Jäger, Andreas; Jepsen, Søren; Cirelli, Joni Augusto; Bourauel, Christoph; Eick, Sigrun; Deschner, James

    2014-01-01

    Obesity is increasing throughout the globe and characterized by excess adipose tissue, which represents a complex endocrine organ. Adipose tissue secrets bioactive molecules called adipokines, which act at endocrine, paracrine, and autocrine levels. Obesity has recently been shown to be associated with periodontitis, a disease characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium, and also with compromised periodontal healing. Although the underlying mechanisms for these associations are not clear yet, increased levels of proinflammatory adipokines, such as leptin, as found in obese individuals, might be a critical pathomechanistic link. The objective of this study was to examine the impact of leptin on the regenerative capacity of human periodontal ligament (PDL) cells and also to study the local leptin production by these cells. Leptin caused a significant downregulation of growth (TGFβ1, and VEGFA) and transcription (RUNX2) factors as well as matrix molecules (collagen, and periostin) and inhibited SMAD signaling under regenerative conditions. Moreover, the local expression of leptin and its full-length receptor was significantly downregulated by inflammatory, microbial, and biomechanical signals. This study demonstrates that the hormone leptin negatively interferes with the regenerative capacity of PDL cells, suggesting leptin as a pathomechanistic link between obesity and compromised periodontal healing.

  15. Thermal regenerative design of a fuel cell cogeneration system

    NASA Astrophysics Data System (ADS)

    Hwang, Jenn-Jiang

    2012-12-01

    The objective of the present work is to design and fabricate a thermal management system (TMS) that commands a proton exchange membrane fuel cell (PEMFC) based cogeneration system to generate the electricity and hot water efficiently. Parametric studies include the external load (PL) and the regenerative temperature (TR). A thermostat valve is employed to optimize the stack operation temperature, while a thermal regenerative unit (TRU) containing a planar heat exchanger is used to recover the heat dissipated by the stack. First, the dynamics of thermal and electrical characteristics such as voltage, current, power, coolant temperature, coolant flow rate, and hydrogen flow rate are measured to check the reliability of the TMS. Then, the effectiveness of the planar heat exchanger is determined to verify the cooling ability of the TRU. Moreover, the transient system efficiencies, including electrical efficiency, thermal efficiency, and overall efficiency are determined. Furthermore, the effect of the regenerative temperature on the time-averaged system efficiencies is examined under different external loads. Finally, an empirical correlation for time-averaged overall efficiency is proposed for helping in design of the PEMFC cogeneration system.

  16. Human dental pulp stem cells: Applications in future regenerative medicine

    PubMed Central

    Potdar, Pravin D; Jethmalani, Yogita D

    2015-01-01

    Stem cells are pluripotent cells, having a property of differentiating into various types of cells of human body. Several studies have developed mesenchymal stem cells (MSCs) from various human tissues, peripheral blood and body fluids. These cells are then characterized by cellular and molecular markers to understand their specific phenotypes. Dental pulp stem cells (DPSCs) are having a MSCs phenotype and they are differentiated into neuron, cardiomyocytes, chondrocytes, osteoblasts, liver cells and β cells of islet of pancreas. Thus, DPSCs have shown great potentiality to use in regenerative medicine for treatment of various human diseases including dental related problems. These cells can also be developed into induced pluripotent stem cells by incorporation of pluripotency markers and use for regenerative therapies of various diseases. The DPSCs are derived from various dental tissues such as human exfoliated deciduous teeth, apical papilla, periodontal ligament and dental follicle tissue. This review will overview the information about isolation, cellular and molecular characterization and differentiation of DPSCs into various types of human cells and thus these cells have important applications in regenerative therapies for various diseases. This review will be most useful for postgraduate dental students as well as scientists working in the field of oral pathology and oral medicine. PMID:26131314

  17. Adipose Tissue-Derived Stem Cells in Regenerative Medicine

    PubMed Central

    Frese, Laura; Dijkman, Petra E.; Hoerstrup, Simon P.

    2016-01-01

    In regenerative medicine, adult stem cells are the most promising cell types for cell-based therapies. As a new source for multipotent stem cells, human adipose tissue has been introduced. These so called adipose tissue-derived stem cells (ADSCs) are considered to be ideal for application in regenerative therapies. Their main advantage over mesenchymal stem cells derived from other sources, e.g. from bone marrow, is that they can be easily and repeatable harvested using minimally invasive techniques with low morbidity. ADSCs are multipotent and can differentiate into various cell types of the tri-germ lineages, including e.g. osteocytes, adipocytes, neural cells, vascular endothelial cells, cardiomyocytes, pancreatic β-cells, and hepatocytes. Interestingly, ADSCs are characterized by immunosuppressive properties and low immunogenicity. Their secretion of trophic factors enforces the therapeutic and regenerative outcome in a wide range of applications. Taken together, these particular attributes of ADSCs make them highly relevant for clinical applications. Consequently, the therapeutic potential of ADSCs is enormous. Therefore, this review will provide a brief overview of the possible therapeutic applications of ADSCs with regard to their differentiation potential into the tri-germ lineages. Moreover, the relevant advancements made in the field, regulatory aspects as well as other challenges and obstacles will be highlighted. PMID:27721702

  18. Fusion and regenerative therapies: is immortality really recessive?

    PubMed

    Stolzing, Alexandra; Hescheler, Jürgen; Sethe, Sebastian

    2007-12-01

    Harnessing cellular fusion as a potential tool for regenerative therapy has been under tentative investigation for decades. A look back the history of fusion experiments in gerontology reveals that whereas some studies indicate that aging-related changes are conserved in fused cells, others have demonstrated that fusion can be used as a tool to revoke cellular senescence and induce tissue regeneration. Recent findings about the role of fusion processes in tissue homeostasis, replenishment, and repair link insights from fusion studies of previous decades with modern developments in stem cell biology and regenerative medicine. We suggest that age-associated loss of regenerative capacity is associated with a decline of effectiveness in stem cell fusion. We project how studies into the fusion of stem cells with tissue cells, or the fusion between activator stem cells and patient cells might help in the development of applications that "rejuvenate" certain target cells, thereby strategically reinstating a regeneration cascade. The outlook is concluded with a discussion of the next research milestones and the potential hazards of fusion therapies.

  19. Human dental pulp stem cells: Applications in future regenerative medicine.

    PubMed

    Potdar, Pravin D; Jethmalani, Yogita D

    2015-06-26

    Stem cells are pluripotent cells, having a property of differentiating into various types of cells of human body. Several studies have developed mesenchymal stem cells (MSCs) from various human tissues, peripheral blood and body fluids. These cells are then characterized by cellular and molecular markers to understand their specific phenotypes. Dental pulp stem cells (DPSCs) are having a MSCs phenotype and they are differentiated into neuron, cardiomyocytes, chondrocytes, osteoblasts, liver cells and β cells of islet of pancreas. Thus, DPSCs have shown great potentiality to use in regenerative medicine for treatment of various human diseases including dental related problems. These cells can also be developed into induced pluripotent stem cells by incorporation of pluripotency markers and use for regenerative therapies of various diseases. The DPSCs are derived from various dental tissues such as human exfoliated deciduous teeth, apical papilla, periodontal ligament and dental follicle tissue. This review will overview the information about isolation, cellular and molecular characterization and differentiation of DPSCs into various types of human cells and thus these cells have important applications in regenerative therapies for various diseases. This review will be most useful for postgraduate dental students as well as scientists working in the field of oral pathology and oral medicine.

  20. Arrayed cellular environments for stem cells and regenerative medicine.

    PubMed

    Titmarsh, Drew M; Chen, Huaying; Wolvetang, Ernst J; Cooper-White, Justin J

    2013-02-01

    The behavior and composition of both multipotent and pluripotent stem cell populations are exquisitely controlled by a complex, spatiotemporally variable interplay of physico-chemical, extracellular matrix, cell-cell interaction, and soluble factor cues that collectively define the stem cell niche. The push for stem cell-based regenerative medicine models and therapies has fuelled demands for increasingly accurate cellular environmental control and enhanced experimental throughput, driving an evolution of cell culture platforms away from conventional culture formats toward integrated systems. Arrayed cellular environments typically provide a set of discrete experimental elements with variation of one or several classes of stimuli across elements of the array. These are based on high-content/high-throughput detection, small sample volumes, and multiplexing of environments to increase experimental parameter space, and can be used to address a range of biological processes at the cell population, single-cell, or subcellular level. Arrayed cellular environments have the capability to provide an unprecedented understanding of the molecular and cellular events that underlie expansion and specification of stem cell and therapeutic cell populations, and thus generate successful regenerative medicine outcomes. This review focuses on recent key developments of arrayed cellular environments and their contribution and potential in stem cells and regenerative medicine.

  1. Adipose Tissue-Derived Stem Cells in Regenerative Medicine.

    PubMed

    Frese, Laura; Dijkman, Petra E; Hoerstrup, Simon P

    2016-07-01

    In regenerative medicine, adult stem cells are the most promising cell types for cell-based therapies. As a new source for multipotent stem cells, human adipose tissue has been introduced. These so called adipose tissue-derived stem cells (ADSCs) are considered to be ideal for application in regenerative therapies. Their main advantage over mesenchymal stem cells derived from other sources, e.g. from bone marrow, is that they can be easily and repeatable harvested using minimally invasive techniques with low morbidity. ADSCs are multipotent and can differentiate into various cell types of the tri-germ lineages, including e.g. osteocytes, adipocytes, neural cells, vascular endothelial cells, cardiomyocytes, pancreatic β-cells, and hepatocytes. Interestingly, ADSCs are characterized by immunosuppressive properties and low immunogenicity. Their secretion of trophic factors enforces the therapeutic and regenerative outcome in a wide range of applications. Taken together, these particular attributes of ADSCs make them highly relevant for clinical applications. Consequently, the therapeutic potential of ADSCs is enormous. Therefore, this review will provide a brief overview of the possible therapeutic applications of ADSCs with regard to their differentiation potential into the tri-germ lineages. Moreover, the relevant advancements made in the field, regulatory aspects as well as other challenges and obstacles will be highlighted.

  2. Regulators of pluripotency and their implications in regenerative medicine

    PubMed Central

    El-Badawy, Ahmed; El-Badri, Nagwa

    2015-01-01

    The ultimate goal of regenerative medicine is to replace damaged tissues with new functioning ones. This can potentially be accomplished by stem cell transplantation. While stem cell transplantation for blood diseases has been increasingly successful, widespread application of stem cell therapy in the clinic has shown limited results. Despite successful efforts to refine existing methodologies and to develop better ones for reprogramming, clinical application of stem cell therapy suffers from issues related to the safety of the transplanted cells, as well as the low efficiency of reprogramming technology. Better understanding of the underlying mechanism(s) involved in pluripotency should accelerate the clinical application of stem cell transplantation for regenerative purposes. This review outlines the main decision-making factors involved in pluripotency, focusing on the role of microRNAs, epigenetic modification, signaling pathways, and toll-like receptors. Of special interest is the role of toll-like receptors in pluripotency, where emerging data indicate that the innate immune system plays a vital role in reprogramming. Based on these data, we propose that nongenetic mechanisms for reprogramming provide a novel and perhaps an essential strategy to accelerate application of regenerative medicine in the clinic. PMID:25960670

  3. Focal epithelial hyperplasia: report of six cases from Ghana, West Africa.

    PubMed

    Nartey, N O; Newman, Merley A; Nyako, E A

    2002-01-01

    Focal epithelial hyperplasia is a proliferative growth of the oral mucosa with distinct clinical and histopathological features. Although focal epithelial hyperplasia is frequently reported in children of American Indian and Eskimo descent, it is rarely seen in Africans. This report presents six new cases of focal epithelial hyperplasia observed in African children. The age of the patients ranged from 4 to 12 years, and all except one were females. Clinical variants, the papillary and the papular types were noted in the same patient. There was spontaneous regression of focal epithelial hyperplasia in four patients during the study period. However, the lesions still persist in two patients three years after the initial presentation.

  4. The Functional Role of Reactive Stroma in Benign Prostatic Hyperplasia

    PubMed Central

    Schauer, Isaiah G.; Rowley, David R.

    2011-01-01

    The human prostate gland is one of the only internal organs that continue to enlarge throughout adulthood. The specific mechanisms that regulate this growth, as well as the pathological changes leading to the phenotype observed in the disease benign prostatic hyperplasia (BPH), are essentially unknown. Recent studies and their associated findings have made clear that many complex alterations occur, involving persistent and chronic inflammation, circulating hormonal level deregulation, and aberrant wound repair processes. BPH has been etiologically characterized as a progressive, albeit discontinuous, hyperplasia of both the glandular epithelial and stromal cell compartments coordinately yielding an expansion of the prostate gland and clinical symptoms. Interestingly, the inflammatory and repair responses observed in BPH are also key components of general wound repair in post-natal tissues. These responses include altered expression of chemokines, cytokines, matrix remodeling factors, chronic inflammatory processes, altered immune surveillance and recognition, as well as the formation of a prototypical ‘reactive’ stroma which is similar to that observed across various fibroplasias and malignancies of a variety of tissue sites. Stromal tissue, both embryonic mesenchyme, and adult reactive stroma myofibroblasts, has been shown to exert potent and functional regulatory control over epithelial proliferation and differentiation as well as immunoresponsive modulation. Thus, the functional biology of a reactive stroma, within the context of an adult disease typified by epithelial and stromal aberrant hyperplasia, is critical to understand within the context of prostate disease and beyond. The mechanisms that regulate reactive stroma biology in BPH represent targets of opportunity for new therapeutic approaches that may extend to other tissue contexts. Accordingly, this review seeks to address the dissection of important factors, signaling pathways, genes, and other

  5. Non-Classical Congenital Adrenal Hyperplasia in Childhood

    PubMed Central

    Kurtoğlu, Selim; Hatipoğlu, Nihal

    2017-01-01

    Congenital adrenal hyperplasia (CAH) is classified as classical CAH and non-classical CAH (NCCAH). In the classical type, the most severe form comprises both salt-wasting and simple virilizing forms. In the non-classical form, diagnosis can be more confusing because the patient may remain asymptomatic or the condition may be associated with signs of androgen excess in the postnatal period or in the later stages of life. This review paper will include information on clinical findings, symptoms, diagnostic approaches, and treatment modules of NCCAH. PMID:27354284

  6. The Next 150 Years of Congenital Adrenal Hyperplasia

    PubMed Central

    Turcu, Adina F.; Auchus, Richard J.

    2015-01-01

    Congenital adrenal hyperplasias (CAH) are a group of autosomal recessive defects in cortisol biosynthesis. Substantial progress has been made since the description of the first report, 150 years ago. This article reviews some of the recent advances in the genetics, diagnosis and treatment of CAH. In addition, we underline the aspects where further progress is required, including, among others, better diagnostic modalities for the mild phenotype and for some of the rare forms of disease, elucidation of epigenetic factors that lead to different phenotypes in patients with identical genotype and expending on treatment options for controlling the adrenal androgen excess. PMID:26047556

  7. Focal epithelial hyperplasia: a multifocal oral human papillomavirus infection.

    PubMed

    Flaitz, C M

    2000-01-01

    Widespread, slightly elevated and confluent nodules are observed throughout the oral mucosa in a young Hispanic girl. Repeated irritation of the soft tissues from a compromised occlusion is an aggravating factor for the spread of these lesions. A diagnosis of focal epithelial hyperplasia, a human papillomavirus infection, is made following histopathologic diagnosis and viral typing. Recognition of this specific type of warts is important in order to avoid the mistaken identification of condyloma acuminata, which may have significant repercussions in the life of a young child.

  8. Oral focal epithelial hyperplasia in a howler monkey (Alouatta fusca).

    PubMed

    Sá, L R; DiLoreto, C; Leite, M C; Wakamatsu, A; Santos, R T; Catão-Dias, J L

    2000-09-01

    Oral focal epithelial hyperplasia is a rare and seldom reported disease in animals and humans induced by a papillomavirus. The present report is the first description of this disease in a Neotropical primate, a howler monkey (Alouatta fusca). The diagnosis was based on gross and microscopic findings. The generic papillomavirus antigen was identified by immunohistochemistry and was found not to be related to any human papillomavirus DNA tested by in situ hybridization. This virus is probably a specific papillomavirus of the howler monkey (HMPV).

  9. A huge benign prostatic hyperplasia presenting with renal failure

    PubMed Central

    Basatac, Cem; Cicek, Mehmet Cagatay

    2015-01-01

    Although transurethral resection of the prostate is still standard of care in many patients suffering from benign prostatic hyperplasia, traditional open prostatectomy (OP) seems as a widely applied method in larger glands. In spite of the fact that holmium laser enucleation can be performed in large glands, upper limits of prostate size in this method are not clearly identified in the current literature. In this case, we aim to report feasibility and efficacy of OP in huge prostate size measured as 680 ml by transrectal ultrasound and review the current literature. PMID:26034239

  10. [Tonsillectomy versus laser tonsillotomy for tonsillar hyperplasia in children].

    PubMed

    Hagedorn, H; Andratschke, M

    2005-04-28

    An appropriate indication for laser tonsillotomy is non-infectious obstructive hyperplasia in children. As a rule, these children suffer from pronounced rhonchopathy, which may be associated with episodes of apnea. Furthermore, disordered articulation and problems with eating have also been described. With increasing age hyperplastic tonsils may repeatedly become inflamed, with the result that tonsillar tissue undergoes changes that further the development of chronic tonsillitis. The indication for tonsillotomy should, however, not be applied in children older than 6 years. In children beyond this age tonsillectomy is recommended, not least due to the fact that the immunological "learning phase" is usually complete around the age of 6.

  11. Congenital Adrenal Hyperplasia and Schmid Metaphyseal Chondrodysplasia in a Child

    PubMed Central

    Khorasani, Efat; Vakili, Rahim

    2016-01-01

    Congenital adrenal hyperplasia (CAH) is a group of hereditary diseases, which are autosomal recessive. CAH occurs due to defect in one of the cortisol coding genes and often clinically presents itself with signs of androgen overproduction. In this article, we report a case of CAH and Schmid metaphyseal dysplasia. Our literature review indicated that this report is the first attempt on CYP11B1 and Schmid dysplasia in a child. The specific diagnosis of 11-β-hydroxylase deficiency can be determined using high basal levels of deoxycorticosterone and/or 11-deoxycortisol serums. PMID:26722148

  12. The next 150 years of congenital adrenal hyperplasia.

    PubMed

    Turcu, Adina F; Auchus, Richard J

    2015-09-01

    Congenital adrenal hyperplasias (CAH) are a group of autosomal recessive defects in cortisol biosynthesis. Substantial progress has been made since the description of the first report, 150 years ago. This article reviews some of the recent advances in the genetics, diagnosis and treatment of CAH. In addition, we underline the aspects where further progress is required, including, among others, better diagnostic modalities for the mild phenotype and for some of the rare forms of disease, elucidation of epigenetic factors that lead to different phenotypes in patients with identical genotype and expending on treatment options for controlling the adrenal androgen excess.

  13. Dominant negative myostatin produces hypertrophy without hyperplasia in muscle.

    PubMed

    Zhu, X; Hadhazy, M; Wehling, M; Tidball, J G; McNally, E M

    2000-05-26

    Myostatin, a TGF-beta family member, is a negative regulator of muscle growth. Here, we generated transgenic mice that expressed myostatin mutated at its cleavage site under the control of a muscle specific promoter creating a dominant negative myostatin. These mice exhibited a significant (20-35%) increase in muscle mass that resulted from myofiber hypertrophy and not from myofiber hyperplasia. We also evaluated the role of myostatin in muscle degenerative states, such as muscular dystrophy, and found significant downregulation of myostatin. Thus, further inhibition of myostatin may permit increased muscle growth in muscle degenerative disorders.

  14. Endometrial thickness predicts endometrial hyperplasia in patients with polycystic ovary syndrome.

    PubMed

    McCormick, Betsy A; Wilburn, Rochelle D; Thomas, Michael A; Williams, Daniel B; Maxwell, Rose; Aubuchon, Mira

    2011-06-30

    Body mass index is predictive of sonographic endometrial stripe thickness, which in turn is predictive of endometrial hyperplasia in patients with polycystic ovary syndrome. For every 1-mm increase in endometrial stripe, the odds ratio of hyperplasia increased by 1.48 (95% confidence interval, 1.04-2.10).

  15. Use of levonorgestrel-releasing intrauterine system in the prevention and treatment of endometrial hyperplasia.

    PubMed

    Ewies, Ayman A A; Alfhaily, Fadi

    2012-11-01

    Endometrial hyperplasia is a commonly seen gynecological condition that affects women of all age groups. Whereas hysterectomy is the most preferred treatment option for complex endometrial hyperplasia with atypia, there is no consensus regarding the first-line management of women with hyperplasia without cytological atypia. Oral progestogen therapy was used with some success. Nonetheless, it may be plausible to argue that women with endometrial hyperplasia need continuous treatment and high level of compliance to ensure complete regression, which may not be guaranteed with oral therapy. Observational studies suggested that levonorgestrel-releasing intrauterine system (LNG-IUS) has been successfully used to treat endometrial hyperplasia without cytological atypia and selected cases of atypical endometrial hyperplasia. Furthermore, there is strong evidence from randomized controlled trials that LNG-IUS prevents the development of endometrial hyperplasia in exogenous estrogen users; however, its protective role and safety in tamoxifen-treated breast cancer survivors remain uncertain. This article evaluates the current evidence for the use of LNG-IUS, releasing 20 μg of LNG per day, in the prevention and treatment of endometrial hyperplasia.

  16. Marked left ventricular hypertrophy mimicking hypertrophic cardiomyopathy associated with steroid therapy for congenital adrenal hyperplasia.

    PubMed

    Scirè, Giuseppe; D'Anella, Giorgio; Cristofori, Laura; Mazzuca, Valentina; Cianfarani, Stefano

    2007-06-01

    We describe a child treated with high-dose steroid therapy for congenital adrenal hyperplasia who showed marked left ventricular hypertrophy mimicking hypertrophic cardiomyopathy associated with steroid therapy for congenital adrenal hyperplasia. Cardiomyopathy reversed completely when an appropriate steroid therapeutic regimen was established.

  17. Mammary fibroadenomatous hyperplasia in a young cat attributed to treatment with megestrol acetate

    PubMed Central

    MacDougall, Lori D.

    2003-01-01

    A male, neutered cat was presented for lethargy, reluctance to walk, and mammary enlargement after recent treatment with megestrol acetate. Mammary fibroadenomatous hyperplasia was diagnosed on the basis of history, clinical signs, and histopathological findings. Pathogenesis, clinical signs, and treatment options for mammary fibroadenomatous hyperplasia attributed to megestrol acetate treatment are discussed. PMID:12677692

  18. Bringing regenerative medicines to the clinic: the future for regulation and reimbursement.

    PubMed

    Bubela, Tania; McCabe, Christopher; Archibald, Peter; Atkins, Harold; Bradshaw, Steven E; Kefalas, Panos; Mujoomdar, Michelle; Packer, Claire; Piret, James; Raxworthy, Mike; Soares, Marta; Viswanathan, Sowmya

    2015-01-01

    Significant investments in regenerative medicine necessitate discussion to align evidentiary requirements and decision-making considerations from regulatory, health system payer and developer perspectives. Only with coordinated efforts will the potential of regenerative medicine be realized. We report on discussions from two workshops sponsored by NICE, University of Alberta, Cell Therapy Catapult and Centre for Commercialization of Regenerative Medicine. We discuss methods to support the assessment of value for regenerative medicine products and services and the synergies that exist between market authorization and reimbursement regulations and practices. We discuss the convergence in novel adaptive licensing practices that may promote the development and adoption of novel therapeutics that meet the needs of healthcare payers.

  19. Theoretical and experimental study on regenerative rotary displacer Stirling engine

    SciTech Connect

    Raggi, L.; Katsuta, Masafumi; Isshiki, Naotsugu; Isshiki, Seita

    1997-12-31

    Recently a quite new type of hot air engine called rotary displacer engine, in which the displacer is a rotating disk enclosed in a cylinder, has been conceived and developed. The working gas, contained in a notch excavated in the disk, is heated and cooled alternately, on account of the heat transferred through the enclosing cylinder that is heated at one side and cooled at the opposite one. The gas temperature oscillations cause the pressure fluctuations that get out mechanical power acting on a power piston. In order to attempt to increase the performances for this kind of engine, the authors propose three different regeneration methods. The first one comprises two coaxial disks that, revolving in opposite ways, cause a temperature gradient on the cylinder wall and a regenerative axial heat conduction through fins shaped on the cylinder inner wall. The other two methods are based on the heat transferred by a proper closed circuit that in one case has a circulating liquid inside and in the other one is formed by several heat pipes working each one for different temperatures. An engine based on the first principle, the Regenerative Tandem Contra-Rotary Displacer Stirling Engine, has been realized and experimented. In this paper experimental results with and without regeneration are reported comparatively with a detailed description of the unity. A basic explanation of the working principle of this engine and a theoretical analysis investigating the main influential parameters for the regenerative effect are done. This new rotating displacer Stirling engines, for their simplicity, are expected to attain high rotational speed especially for applications as demonstration and hobby unities.

  20. Regenerative thermal oxidation for non-conventional applications

    SciTech Connect

    Gosselin, G.; Gravel, J.J.O.

    1999-07-01

    Regenerative Thermal Oxidation has been applied by Biothermica to treat non-conventional emissions. These emissions include pollutants as VOC, COC, TRS, PAH, PCB, HCl and odors. In the kraft pulping industry, environmental requirements for reduced emissions of total reduced sulfur (TRS) and volatile organic compounds (VOC) from pulping operations are leading to incinerators of high destruction efficiency and thermal performance. The first installation in Canada of a Regenerative Thermal Oxidation (RTO) was placed in service early in 1997 at a kraft pulp mill in the province of Quebec. Tests have shown a TRS reduction of 99.6% with a thermal efficiency of 88.5% in the RTO. It can be considered the best method to comply with the new norms for TRS atmospheric emissions in the pulp and paper industry. In the primary aluminum process, a marked improvement in anode properties can be gained by preparing the paste at high temperature, followed by cooling with a water addition in an intensive mixer. However, the addition of cooling water results in a large increase in the emissions of VOC and PAH which can prejudice the process. A number of emission control processes were evaluated. An improved Regenerative Thermal Oxidation (RTO) unit was installed in a modern aluminum plant in Canada. The emissions of VOCs and PAHs from an EIRICH intensive mixer-cooler were reduced by more than 99.9% while all troublesome deposits in the fumes collection system were eliminated. This enabled the plant to remain well within the emission levels allowed by the environmental authority while enjoying considerable benefits from improved anode qualities. In the asphalt roofing industry, RTO was applied to treat the VOC and COC emissions and several units have been in operation since 1990. In the United States two units were installed in asphalt shingle plants and new features in the process show a VOC and COC reduction of 99%.

  1. Cell/tissue processing information system for regenerative medicine.

    PubMed

    Iwayama, Daisuke; Yamato, Masayuki; Tsubokura, Tetsuya; Takahashi, Minoru; Okano, Teruo

    2016-11-01

    When conducting clinical studies of regenerative medicine, compliance to good manufacturing practice (GMP) is mandatory, and thus much time is needed for manufacturing and quality management. It is therefore desired to introduce the manufacturing execution system (MES), which is being adopted by factories manufacturing pharmaceutical products. Meanwhile, in manufacturing human cell/tissue processing autologous products, it is necessary to protect patients' personal information, prevent patients from being identified and obtain information for cell/tissue identification. We therefore considered it difficult to adopt conventional MES to regenerative medicine-related clinical trials, and so developed novel software for production/quality management to be used in cell-processing centres (CPCs), conforming to GMP. Since this system satisfies the requirements of regulations in Japan and the USA for electronic records and electronic signatures (ER/ES), the use of ER/ES has been allowed, and the risk of contamination resulting from the use of recording paper has been eliminated, thanks to paperless operations within the CPC. Moreover, to reduce the risk of mix-up and cross-contamination due to contact during production, we developed a touchless input device with built-in radio frequency identification (RFID) reader-writer devices and optical sensors. The use of this system reduced the time to prepare and issue manufacturing instructions by 50% or more, compared to the conventional handwritten system. The system contributes to producing more large-scale production and to reducing production costs for cell and tissue products in regenerative medicine. Copyright © 2014 John Wiley & Sons, Ltd.

  2. Integration of regenerative shock absorber into vehicle electric system

    NASA Astrophysics Data System (ADS)

    Zhang, Chongxiao; Li, Peng; Xing, Shaoxu; Kim, Junyoung; Yu, Liangyao; Zuo, Lei

    2014-03-01

    Regenerative/Energy harvesting shock absorbers have a great potential to increase fuel efficiency and provide suspension damping simultaneously. In recent years there's intensive work on this topic, but most researches focus on electricity extraction from vibration and harvesting efficiency improvement. The integration of electricity generated from regenerative shock absorbers into vehicle electric system, which is very important to realize the fuel efficiency benefit, has not been investigated. This paper is to study and demonstrate the integration of regenerative shock absorber with vehicle alternator, battery and in-vehicle electrical load together. In the presented system, the shock absorber is excited by a shaker and it converts kinetic energy into electricity. The harvested electricity flows into a DC/DC converter which realizes two functions: controlling the shock absorber's damping and regulating the output voltage. The damping is tuned by controlling shock absorber's output current, which is also the input current of DC/DC converter. By adjusting the duty cycles of switches in the converter, its input impedance together with input current can be adjusted according to dynamic damping requirements. An automotive lead-acid battery is charged by the DC/DC converter's output. To simulate the working condition of combustion engine, an AC motor is used to drive a truck alternator, which also charges the battery. Power resistors are used as battery's electrical load to simulate in-vehicle electrical devices. Experimental results show that the proposed integration strategy can effectively utilize the harvested electricity and power consumption of the AC motor is decreased accordingly. This proves the combustion engine's load reduction and fuel efficiency improvement.

  3. New approaches to the quantitation of hypertrophy and hyperplasia in hepatomegaly.

    PubMed

    Carthew, P; Edwards, R E; Nolan, B M

    1998-12-28

    A histological method utilizing the optical dissector principle has been developed for determining the contribution of hypertrophy and hyperplasia to the hepatomegaly induced by the peroxisome proliferator gemfibrozil. The optical dissector is a technique derived from the 'new stereology' and has been used to estimate the number of hepatocyte nuclear profiles, that are present in a reference volume of tissue. The overall changes due to hypertrophy and hyperplasia in the rat liver after gemfibrozil treatment, did not reach significance, although the zonal hypertrophy change did. This indicated that although there was a 20% increase in liver weight with treatment, the hepatomegaly was caused by a combination of hypertrophy and hyperplasia, neither of which, on its own, was significantly different from the control values. The distinction of hyperplasia from hypertrophy, using a purely histological method, will be useful in assessing whether treatment related sustained hyperplasia is occurring in the liver.

  4. Advances and new frontiers in the pathophysiology of venous neointimal hyperplasia and dialysis access stenosis.

    PubMed

    Lee, Timmy; Roy-Chaudhury, Prabir

    2009-09-01

    Hemodialysis vascular access dysfunction is a major cause of morbidity and mortality in hemodialysis patients. The most common cause of this vascular access dysfunction is venous stenosis as a result of venous neointimal hyperplasia within the perianastomotic region (arteriovenous fistula) or at the graft-vein anastomosis (polytetrafluoroethylene, or PTFE, grafts). There have been few effective treatments to date for venous neointimal hyperplasia, in part, because of the poor understanding of the pathogenesis of venous neointimal hyperplasia. Therefore, this article will (1) describe the pathology of hemodialysis access stenosis in arteriovenous fistulas and grafts, (2) review and describe both current and novel concepts in the pathogenesis of neointimal hyperplasia formation, (3) discuss current and future novel therapies for treating venous neointimal hyperplasia, and (4) suggest future research areas in the field of hemodialysis vascular access dysfunction.

  5. Advances and New Frontiers in the Pathophysiology of Venous Neointimal Hyperplasia and Dialysis Access Stenosis

    PubMed Central

    Lee, Timmy; Roy-Chaudhury, Prabir

    2009-01-01

    Hemodialysis vascular access dysfunction is a major cause of morbidity and mortality in hemodialysis patients. The most common cause of this vascular access dysfunction is venous stenosis as a result of venous neointimal hyperplasia within the peri-anastomotic region (AV fistula) or at the graft-vein anastomosis (PTFE grafts). There have been few effective treatments to-date for venous neointimal hyperplasia in part because of the poor understanding of the pathogenesis of venous neointimal hyperplasia. Therefore, this article will (1) describe the pathology of hemodialysis access stenosis in AV fistulas and grafts, (2) review and describe both current and novel concepts in the pathogenesis of neointimal hyperplasia formation, (3) discuss current and future novel therapies for treating venous neointimal hyperplasia, and (4) suggest future research areas in the field of hemodialysis vascular access dysfunction. PMID:19695501

  6. Effect of Phellius linteus water extract on benign prostatic hyperplasia

    PubMed Central

    Kim, Yu-Na; Kim, Min-Sun; Chun, Sung-Sik

    2013-01-01

    Benign prostatic hyperplasia (BPH) is one of the most common diseases among elderly men. As the old-age population is increasing recently, it is to our interest to observe the growing BPH within them. In BPH, the dihydrotestosterone (DHT) acts as promotes prostate growth. It inhibits enzyme 5α-reductase that is involved in the conversion of testosterone to the DHT activity which reduces the excessive prostate growth. Through experiments, the effects of Phellius linteus water extract performed on the BPH rats were induced by testosterone treatments. For 12 weeks, Sprague-Dawley rats were treated with testosterone for the induction of BPH. Rats were divided into four experimental groups: the not treated group (N), the testosterone injection and D.W treatment group (TN), the testosterone injection and Phellinus linteus treatment group (TP) and testosterone injection and finasteride treatment group (TF). Prostate weight, volume and weight ratio in the TP group and the TF group were significantly lower than the TN group. Testosterone and DHT levels in the TN group were significantly higher than that of the N group. And the TP group was significantly decreased than that of the TN group. While prostates of control rats revealed severe acinar gland atrophy and stromal proliferation; the TP and TF groups showed trophic symptoms and were lined by flattened epithelial cells, thus, the stromal proliferation is relatively low as compared to the TN group. These suggest that Phellinus linteus water extracts may be an useful remedy for treating the benign prostatic hyperplasia. PMID:23766877

  7. Korean clinical practice guideline for benign prostatic hyperplasia

    PubMed Central

    Yeo, Jeong Kyun; Choi, Hun; Bae, Jae Hyun; Kim, Jae Heon; Yang, Seong Ok; Oh, Chul Young; Cho, Young Sam; Kim, Kyoung Woo

    2016-01-01

    In 2014, the Korean Urological Association organized the Benign Prostatic Hyperplasia Guideline Developing Committee composed of experts in the field of benign prostatic hyperplasia (BPH) with the participation of the Korean Academy of Family Medicine and the Korean Continence Society to develop a Korean clinical practice guideline for BPH. The purpose of this clinical practice guideline is to provide current and comprehensive recommendations for the evaluation and treatment of BPH. The committee developed the guideline mainly by adapting existing guidelines and partially by using the de novo method. A comprehensive literature review was carried out primarily from 2009 to 2013 by using medical search engines including data from Korea. Based on the published evidence, recommendations were synthesized, and the level of evidence of the recommendations was determined by using methods adapted from the 2011 Oxford Centre for Evidence-Based Medicine. Meta-analysis was done for one key question and four recommendations. A draft guideline was reviewed by expert peer reviewers and discussed at an expert consensus meeting until final agreement was achieved. This evidence-based guideline for BPH provides recommendations to primary practitioners and urologists for the diagnosis and treatment of BPH in men older than 40 years. PMID:26966724

  8. Enhanced hyperplasia in muscles of transgenic zebrafish expressing Follistatin1.

    PubMed

    Li, Xi; Nie, Fen; Yin, Zhan; He, JiangYan

    2011-02-01

    Myostatin is a member of the transforming growth factor-β (TGF-β) super-family and functions as a negative regulator of muscle growth. Binding of the specific receptor, Activin receptor IIB (Act RIIB), with myostatin or other related TGF-β members, could be inhibited by the activin-binding protein follistatin (Fst) in mammals. Overexpressing Fst in mouse skeletal muscle leads to muscle hypertrophy and hyperplasia. To determine if Fst has similar roles in fish, we generated transgenic zebrafish expressing high levels of zebrafish Fst1 using the promoter of the zebrafish skeletal muscle-specific gene, myosin, light polypeptide 2, skeletal muscle (Mylz2). Independent transgenic zebrafish lines exhibited elevated expression levels of myogenic regulatory genes MyoD and Pax7 in muscle cells. Adult Fst1 overexpressing transgenic zebrafish exhibited a slight body weight increase. The high level of Fst1 expression dramatically increased myofiber numbers in skeletal muscle, without significantly changing the fiber size. Our findings suggest that Fst1 overexpression can promote zebrafish muscle growth by enhancing myofiber hyperplasia.

  9. Altered catecholamine receptor affinity in rabbit aortic intimal hyperplasia

    SciTech Connect

    O'Malley, M.K.; Cotecchia, S.; Hagen, P.O. )

    1991-08-01

    Intimal thickening is a universal response to endothelial denudation and is also thought to be a precursor of atherosclerosis. The authors have demonstrated selective supersensitivity in arterial intimal hyperplasia to norepinephrine and they now report a possible mechanism for this. Binding studies in rabbit aorta with the selective alpha 1-adrenergic radioligand 125I-HEAT demonstrated that there was no change in receptor density (20 {plus minus} 4 fmole/10(6) cells) in intact vascular smooth muscle cells at either 5 or 14 days after denudation. However, competition studies showed a 2.6-fold increase in alpha 1-adrenergic receptor affinity for norepinephrine in intimal hyperplastic tissue (P less than 0.05). This increased affinity for norepinephrine was associated with a greater increase in 32P-labeled phosphatidylinositol (148% intimal thickening versus 76% control) and phosphatidic acid (151% intimal thickening versus 56% control) following norepinephrine stimulation of free floating rings of intimal hyperplastic aorta. These data suggest that the catecholamine supersensitivity in rabbit aortic intimal hyperplasia is receptor mediated and may be linked to the phosphatidylinositol cycle.

  10. Surgical management of mandibular condylar hyperplasia type 1

    PubMed Central

    Morales-Ryan, Carlos A.; García-Morales, Patricia; Perez, Daniel

    2009-01-01

    This study compared outcomes of two surgical methods for patients diagnosed with active condylar hyperplasia type 1. Group 1 (n = 12) was treated with orthognathic surgery only, while group 2 (n = 42) was treated with high condylectomies, articular disc repositioning, and orthognathic surgery. There was no statistically significant difference between the two groups for maximum incisal opening, lateral excursions, and subjective jaw function before surgery. Group 2 showed more active presurgical mandibular growth (P < 0.05). At long-term follow up, no differences were found in lateral excursions and subjective jaw function. Group 2 showed a greater increase in maximum incisal opening (P < 0.01) and stability (P < 0.05) at long-term follow-up. All of the patients in group 1 grew back into skeletal and occlusal Class III relationships requiring secondary intervention, whereas all patients in group 2 remained stable in a Class I skeletal and occlusal relationship. Thus, patients with active condylar hyperplasia treated with high condylectomy, articular disc repositioning, and orthognathic surgery had stable, predictable outcomes compared with those treated with orthognathic surgery only. The high condylectomy effectively arrests disproportionate mandibular growth while maintaining normal jaw function. PMID:19865502

  11. High Pressure Regenerative Turbine Engine: 21st Century Propulsion

    NASA Technical Reports Server (NTRS)

    Lear, W. E.; Laganelli, A. L.; Senick, Paul (Technical Monitor)

    2001-01-01

    A novel semi-closed cycle gas turbine engine was demonstrated and was found to meet the program goals. The proof-of-principle test of the High Pressure Regenerative Turbine Engine produced data that agreed well with models, enabling more confidence in designing future prototypes based on this concept. Emission levels were significantly reduced as predicted as a natural attribute of this power cycle. Engine testing over a portion of the operating range allowed verification of predicted power increases compared to the baseline.

  12. Status of the Regenerative ECLSS Water Recovery System

    NASA Technical Reports Server (NTRS)

    Bagdigian, Robert M.; Carter, D. Layne; Bedard, John

    2007-01-01

    NASA is developing a regenerative water recovery system (WRS) for deployment on the International Space Station (ISS), The major assemblies included in this system are the Water Processor Assembly (WPA) and Urine Processor Assembly (UPA). The WPA has been developed by Hamilton Sundstrand Space Systems International (HSSSI), Inc., while the UPA has been developed by the Marshall Space Flight Center (MSFC). Test and verification activities have been completed for the system and planning for launch and on-orbit activation is underway. This paper summarizes the status as of April 2007 and describes some of the technical challenges encountered and lessons learned over the past year.

  13. A Possible Regenerative, Molten-Salt, Thermoelectric Fuel Cell

    NASA Technical Reports Server (NTRS)

    Greenberg, Jacob; Thaller, Lawrence H.; Weber, Donald E.

    1964-01-01

    Molten or fused salts have been evaluated as possible thermoelectric materials because of the relatively good values of their figures of merit, their chemical stability, their long liquid range, and their ability to operate in conjunction with a nuclear reactor to produce heat. In general, molten salts are electrolytic conductors; therefore, there will be a transport of materials and subsequent decomposition with the passage of an electric current. It is possible nonetheless to overcome this disadvantage by using the decomposition products of the molten-salt electrolyte in a fuel cell. The combination of a thermoelectric converter and a fuel cell would lead to a regenerative system that may be useful.

  14. Regenerative Medicine for Epilepsy: From Basic Research to Clinical Application

    PubMed Central

    Yasuhara, Takao; Agari, Takashi; Kameda, Masahiro; Kondo, Akihiko; Kuramoto, Satoshi; Jing, Meng; Sasaki, Tatsuya; Toyoshima, Atsuhiko; Sasada, Susumu; Sato, Kenichiro; Shinko, Aiko; Wakamori, Takaaki; Okuma, Yu; Miyoshi, Yasuyuki; Tajiri, Naoki; Borlongan, Cesario V.; Date, Isao

    2013-01-01

    Epilepsy is a chronic neurological disorder, which presents with various forms of seizures. Traditional treatments, including medication using antiepileptic drugs, remain the treatment of choice for epilepsy. Recent development in surgical techniques and approaches has improved treatment outcomes. However, several epileptic patients still suffer from intractable seizures despite the advent of the multimodality of therapies. In this article, we initially provide an overview of clinical presentation of epilepsy then describe clinically relevant animal models of epilepsy. Subsequently, we discuss the concepts of regenerative medicine including cell therapy, neuroprotective agents, and electrical stimulation, which are reviewed within the context of our data. PMID:24287913

  15. Propellant feed system of a regeneratively cooled scramjet

    SciTech Connect

    Kanda, Takeshi; Masuya, Goro; Wakamatsu, Yoshio )

    1991-04-01

    An expander cycle for an airframe-integrated hydrogen-fueled scramjet is analyzed to study regenerative cooling characteristics and overall specific impulse. Below Mach 10, the specific impulse and thrust coincide with the reference values. At Mach numbers above 10, a reduction of the specific impulse occurs due to the coolant flow rate requirement, which is accompanied by an increase of thrust. It is shown that the thrust may be increased by injecting excess fuel into the combustor to compensate for the decrease of the specific impulse. 9 refs.

  16. An alexandrite regenerative amplifier for water vapor and temperature measurements

    NASA Technical Reports Server (NTRS)

    Thro, P.-Y.; Boesenberg, J.; Wulfmeyer, V.

    1992-01-01

    The Differential Absorption Lidar (DIAL) technique is a powerful method for determining meteorological parameters, but it requires high quality of the laser source: high energy, very narrow bandwidth, high wavelength stability, and spectral purity. Although many efforts have been made to improve the lasers in view of these aspects, a satisfactory solution has not been demonstrated up to now. We describe a regenerative amplifier, using a Ti:sapphire laser as master oscillator and an alexandrite laser as slave amplifier, which is expected to meet the requirements for water vapor concentration and temperature measurements.

  17. Alexandrite-pumped alexandrite regenerative amplifier for femtosecond pulse amplification

    SciTech Connect

    Hariharan, A.; Fermann, M.E.; Stock, M.L.; Harter, D.J.; Squier, J.

    1996-01-01

    We demonstrate a regenerative amplifier incorporating alexandrite as the gain medium that is pumped by an alexandrite laser. Temperature-altered gain permitted the 728-nm alexandrite pump laser, operating at room temperature, to pump a 780{endash}800-nm alexandrite laser that was maintained at elevated temperatures. 200-fs pulses from a Ti:sapphire oscillator were amplified to the millijoule level. This system also amplified femtosecond pulses from a frequency-doubled Er-doped fiber laser. {copyright} {ital 1996 Optical Society of America.}

  18. A regenerative CO2 amplifier with controlled pulse duration

    NASA Astrophysics Data System (ADS)

    Apollonov, V. V.; Kazakov, K. Kh.; Sorochenko, V. R.; Shakir, Iu. A.

    1991-03-01

    The paper reports the development of a regenerative TEA CO2 amplifier with the pulse duration in a train controlled within the range from 10 to 40 ns, the interval between the pulses amounting to 110 ns and their total energy amounting to 4 J. Laser radiation screening by an optical-air-breakdown plasma in a lens telescope focus was used to form the injected pulse. Good reproduction of the temporal parameters of the injected pulse was achieved by virtue of the injection of radiation from a frequency stabilized CW CO2-laser into the master oscillator.

  19. Regenerative fuel cells for space and terrestrial use

    NASA Astrophysics Data System (ADS)

    Tillmetz, Werner; Dietrich, Guenther; Benz, Uwe

    Electrolysis, fuel cell, and energy storage technologies are compared and evaluated. The use of a fuel cell and electrolyzer with an immobilized electrolyte is selected as the most promising technique. A comparison of the batteries demonstrates that a RFCS (regenerative fuel cell system) could be a serious competitor in future space activities, especially with increasing power level and energy to be stored. Also, for many terrestrial applications, highly efficient energy storage systems will be of great interest in the near future. Aspects of the terrestrial use of a RFCS are discussed.

  20. Performance of a transpiration-regenerative cooled rocket thrust chamber

    NASA Technical Reports Server (NTRS)

    Valler, H. W.

    1979-01-01

    The analysis, design, fabrication, and testing of a liquid rocket engine thrust chamber which is gas transpiration cooled in the high heat flux convergent portion of the chamber and water jacket cooled (simulated regenerative) in the barrel and divergent sections of the chamber are described. The engine burns LOX-hydrogen propellants at a chamber pressure of 600 psia. Various transpiration coolant flow rates were tested with resultant local hot gas wall temperatures in the 800 F to 1400 F range. The feasibility of transpiration cooling with hydrogen and helium, and the use of photo-etched copper platelets for heat transfer and coolant metering was successfully demonstrated.

  1. Analysing regenerative potential in zebrafish models of congenital muscular dystrophy.

    PubMed

    Wood, A J; Currie, P D

    2014-11-01

    The congenital muscular dystrophies (CMDs) are a clinically and genetically heterogeneous group of muscle disorders. Clinically hypotonia is present from birth, with progressive muscle weakness and wasting through development. For the most part, CMDs can mechanistically be attributed to failure of basement membrane protein laminin-α2 sufficiently binding with correctly glycosylated α-dystroglycan. The majority of CMDs therefore arise as the result of either a deficiency of laminin-α2 (MDC1A) or hypoglycosylation of α-dystroglycan (dystroglycanopathy). Here we consider whether by filling a regenerative medicine niche, the zebrafish model can address the present challenge of delivering novel therapeutic solutions for CMD. In the first instance the readiness and appropriateness of the zebrafish as a model organism for pioneering regenerative medicine therapies in CMD is analysed, in particular for MDC1A and the dystroglycanopathies. Despite the recent rapid progress made in gene editing technology, these approaches have yet to yield any novel zebrafish models of CMD. Currently the most genetically relevant zebrafish models to the field of CMD, have all been created by N-ethyl-N-nitrosourea (ENU) mutagenesis. Once genetically relevant models have been established the zebrafish has several important facets for investigating the mechanistic cause of CMD, including rapid ex vivo development, optical transparency up to the larval stages of development and relative ease in creating transgenic reporter lines. Together, these tools are well suited for use in live-imaging studies such as in vivo modelling of muscle fibre detachment. Secondly, the zebrafish's contribution to progress in effective treatment of CMD was analysed. Two approaches were identified in which zebrafish could potentially contribute to effective therapies. The first hinges on the augmentation of functional redundancy within the system, such as upregulating alternative laminin chains in the candyfloss

  2. Controlling life: from Jacques Loeb to regenerative medicine.

    PubMed

    Maienschein, Jane

    2009-01-01

    In his 1987 book Controlling Life: Jacques Loeb and the Engineering Ideal in Biology, Philip Pauly presented his readers with the biologist Jacques Loeb and his role in developing an emphasis on control of life processes. Loeb's work on artificial parthenogenesis, for example, provided an example of bioengineering at work. This paper revisits Pauly's study of Loeb and explores the way current research in regenerative medicine reflects the same tradition. A history of regeneration research reveals patterns of thinking and research methods that both echo Loeb's ideology and point the way to modern studies. Pauly's work revealed far more than we readers realized at the time of its publication.

  3. Complement-triggered pathways orchestrate regenerative responses throughout phylogenesis

    PubMed Central

    Mastellos, Dimitrios C.; DeAngelis, Robert A.; Lambris, John D.

    2014-01-01

    Adult tissue plasticity, cell reprogramming, and organ regeneration are major challenges in the field of modern regenerative medicine. Devising strategies to increase the regenerative capacity of tissues holds great promise for dealing with donor organ shortages and low transplantation outcomes and also provides essential impetus to tissue bioengineering approaches for organ repair and replacement. The inherent ability of cells to reprogram their fate by switching into an embryonic-like, pluripotent progenitor state is an evolutionary vestige that in mammals has been retained mostly in fetal tissues and persists only in a few organs of the adult body. Tissue regeneration reflects the capacity of terminally differentiated cells to re-enter the cell cycle and proliferate in response to acute injury or environmental stress signals. In lower vertebrates, this regenerative capacity extends to several organs and remarkably culminates in precise tissue patterning, through cellular transdifferentiation and complex morphogenetic processes that can faithfully reconstruct entire body parts. Many lessons have been learned from robust regeneration models in amphibians such as the newt and axolotl. However, the dynamic interactions between the regenerating tissue, the surrounding stroma, and the host immune response, as it adapts to the actively proliferating tissue, remain ill-defined. The regenerating zone, through a sequence of distinct molecular events, adopts phenotypic plasticity and undergoes rigorous tissue remodeling that, in turn, evokes a significant inflammatory response. Complement is a primordial sentinel of the innate immune response that engages in multiple inflammatory cascades as it becomes activated during tissue injury and remodeling. In this respect, complement proteins have been implicated in tissue and organ regeneration in both urodeles and mammals. Distinct complement-triggered pathways have been shown to modulate critical responses that promote tissue

  4. Hybrid regenerative fuel cell systems for space applications

    NASA Technical Reports Server (NTRS)

    Saucier, David R.

    1988-01-01

    This paper describes a hybrid regenerative fuel cell (RFC) system for space application, which is made up of an alkaline fuel cell (Space Shuttle fuel cell) and an acid electrolysis unit (solid polymer electrolyte). In the RFC, gas produced from the acid electrolysis unit and water produced by the alkaline fuel cell are repeatedly reacted in the other unit. The results of RFC's tests indicate that the system is feasible in terms of fluid/unit compatibility. In addition, the fuel cell thermal-control system proved capable of controlling fuel cell temperatures throughout long open-circuit periods. Diagrams of the RFC and its subsystems are included.

  5. NASA Lewis Evaluation of Regenerative Fuel Cell (RFC) Systems

    NASA Technical Reports Server (NTRS)

    Hagedorn, N. H.; Gonzalez-Sanabria, O. D; Kohout, L. L.

    1986-01-01

    Evaluation of two regenerative fuel cell (RFC) systems was begun in-house, and under contracts and grants. The passive hydrogen-oxygen RFC offers the possibility of a high-energy density, long-life storage system for geosynchronous Earth orbit missions. The hydrogen-bromine RFC offers the combination of high efficiency and moderate energy density that could ideally suit low Earth orbit missions if successfully developed. Either or both of these systems would be attractive additions to the storage options available to designers of future missions.

  6. Long life Regenerative Fuel Cell technology development plan

    NASA Technical Reports Server (NTRS)

    Littman, Franklin D.; Cataldo, Robert L.; Mcelroy, James F.; Stedman, Jay K.

    1992-01-01

    This paper summarizes a technology roadmap for completing advanced development of a Proton Exchange Membrane (PEM) Regenerative Fuel Cell (RFC) to meet long life (20,000 hrs at 50 percent duty cycle) mobile or portable power system applications on the surface of the moon and Mars. Development of two different sized RFC power system modules is included in this plan (3 and 7.5 kWe). A conservative approach was taken which includes the development of a Ground Engineering System, Qualification Unit, and Flight Unit. This paper includes a concept description, technology assessment, development issues, development tasks, and development schedule.

  7. Severe systemic toxicity and urinary bladder cytotoxicity and regenerative hyperplasia induced by arsenite in arsenic (+3 oxidation state) methyltransferase knockout mice. A preliminary report

    EPA Science Inventory

    Arsenic (+3 oxidation state) methyltransferase (As3mt) catalyzes reactions which convert inorganic arsenic to methylated metabolites. This study determined whether the As3mt null genotype in the mouse modifies cytotoxic and proliferative effects seen in urinary bladders of wild t...

  8. Regeneratively cooled rocket engine for space storable propellants

    NASA Technical Reports Server (NTRS)

    Wagner, W. R.; Waldman, B. J.

    1973-01-01

    Analyses and experimental studies were performed with the OF2 (F2/O2)/B2H6 propellant combination over a range in operating conditions to determine suitability for a space storable pressure fed engine configuration for an extended flight space vehicle configuration. The regenerative cooling mode selected for the thrust chamber was explored in detail with the use of both the fuel and oxidizer as coolants in an advanced milled channel construction thrust chamber design operating at 100 psia chamber pressure and a nominal mixture ratio of 3.0 with a 60:1 area ratio nozzle. Benefits of the simultaneous cooling as related to gaseous injection of both fuel and oxidizer propellants were defined. Heat transfer rates, performance and combustor stability were developed for impinging element triplet injectors in uncooled copper calorimeter hardware with flow, pressure and temperature instrumentation. Evaluation of the capabilities of the B2H6 and OF2 during analytical studies and numerous tests with flow through electrically heated blocks provided design criteria for subsequent regenerative chamber design and fabrication.

  9. Regenerative Medicine for Periodontal and Peri-implant Diseases

    PubMed Central

    Larsson, L.; Decker, A.M.; Nibali, L.; Pilipchuk, S.P.; Berglundh, T.; Giannobile, W.V.

    2015-01-01

    The balance between bone resorption and bone formation is vital for maintenance and regeneration of alveolar bone and supporting structures around teeth and dental implants. Tissue regeneration in the oral cavity is regulated by multiple cell types, signaling mechanisms, and matrix interactions. A goal for periodontal tissue engineering/regenerative medicine is to restore oral soft and hard tissues through cell, scaffold, and/or signaling approaches to functional and aesthetic oral tissues. Bony defects in the oral cavity can vary significantly, ranging from smaller intrabony lesions resulting from periodontal or peri-implant diseases to large osseous defects that extend through the jaws as a result of trauma, tumor resection, or congenital defects. The disparity in size and location of these alveolar defects is compounded further by patient-specific and environmental factors that contribute to the challenges in periodontal regeneration, peri-implant tissue regeneration, and alveolar ridge reconstruction. Efforts have been made over the last few decades to produce reliable and predictable methods to stimulate bone regeneration in alveolar bone defects. Tissue engineering/regenerative medicine provide new avenues to enhance tissue regeneration by introducing bioactive models or constructing patient-specific substitutes. This review presents an overview of therapies (e.g., protein, gene, and cell based) and biomaterials (e.g., resorbable, nonresorbable, and 3-dimensionally printed) used for alveolar bone engineering around teeth and implants and for implant site development, with emphasis on most recent findings and future directions. PMID:26608580

  10. Johnson Space Center's Regenerative Life Support Systems Test Bed.

    PubMed

    Barta, D J; Henninger, D L

    1996-01-01

    The Regenerative Life Support Systems (RLSS) Test Bed at NASA's Johnson Space Center is an atmospherically closed, controlled environment facility for human testing of regenerative life support systems using higher plants in conjunction with physicochemical life support systems. The facility supports NASA's Advanced Life Support (ALS) Program. The facility is comprised of two large scale plant growth chambers, each with approximately 11 m2 growing area. The root zone in each chamber is configurable for hydroponic or solid media plant culture systems. One of the two chambers, the Variable Pressure Growth Chamber (VPGC), is capable of operating at lower atmospheric pressures to evaluate a range of environments that may be used in a planetary surface habitat; the other chamber, the Ambient Pressure Growth Chamber (APGC) operates at ambient atmospheric pressure. The air lock of the VPGC is currently being outfitted for short duration (1 to 15 day) human habitation at ambient pressures. Testing with and without human subjects will focus on 1) integration of biological and physicochemical air and water revitalization systems; 2) effect of atmospheric pressure on system performance; 3) planetary resource utilization for ALS systems, in which solid substrates (simulated planetary soils or manufactured soils) are used in selected crop growth studies; 4) environmental microbiology and toxicology; 5) monitoring and control strategies; and 6) plant growth systems design. Included are descriptions of the overall design of the test facility, including discussions of the atmospheric conditioning, thermal control, lighting, and nutrient delivery systems.

  11. Repair Injured Heart by Regulating Cardiac Regenerative Signals

    PubMed Central

    Wang, Lei; Paul, Christian

    2016-01-01

    Cardiac regeneration is a homeostatic cardiogenic process by which the sections of malfunctioning adult cardiovascular tissues are repaired and renewed employing a combination of both cardiomyogenesis and angiogenesis. Unfortunately, while high-quality regeneration can be performed in amphibians and zebrafish hearts, mammalian hearts do not respond in kind. Indeed, a long-term loss of proliferative capacity in mammalian adult cardiomyocytes in combination with dysregulated induction of tissue fibrosis impairs mammalian endogenous heart regenerative capacity, leading to deleterious cardiac remodeling at the end stage of heart failure. Interestingly, several studies have demonstrated that cardiomyocyte proliferation capacity is retained in mammals very soon after birth, and cardiac regeneration potential is correspondingly preserved in some preadolescent vertebrates after myocardial infarction. There is therefore great interest in uncovering the molecular mechanisms that may allow heart regeneration during adult stages. This review will summarize recent findings on cardiac regenerative regulatory mechanisms, especially with respect to extracellular signals and intracellular pathways that may provide novel therapeutics for heart diseases. Particularly, both in vitro and in vivo experimental evidences will be presented to highlight the functional role of these signaling cascades in regulating cardiomyocyte proliferation, cardiomyocyte growth, and maturation, with special emphasis on their responses to heart tissue injury. PMID:27799944

  12. Feasibility study of a simple unitized regenerative fuel cell

    NASA Astrophysics Data System (ADS)

    Verma, A.; Basu, S.

    Conventional fuel cells use hydrogen and oxygen as the fuel and oxidant, respectively. Hydrogen and oxygen can be produced through electrolysis of water in an electrochemical cell. A simple unitized regenerative fuel cell (URFC), by combining an electrolyzer and a fuel cell, is constructed to check the feasibility of such a device. In the first cycle, hydrogen and oxygen gases are generated from water containing NaHCO 3 when a given dc voltage is applied across Ni-Co/stainless steel electrodes. A solar photovoltaic cell is also used to provide the power. The generated gases are trapped between their respective electrodes and nylon mesh. In the second cycle, the hydrogen and oxygen gases are used in the same electrochemical cell (fuel cell) to produce electricity under a specific load. The current density and voltage are measured by varying different parameters, e.g., time of electrolysis, magnitude of voltage applied, and electrolyte concentration. An open-circuit voltage (OCV) of 1.3 V is obtained from two regenerative fuel cells in series with a total active electrode area of 300 cm 2. A current density of about 0.5 mA cm -2 is generated using 0.5N NaHCO 3 when 4.5 V is applied for 25 min. A maximum power of 36.5 mW is obtained at 0.21 mA cm -2.

  13. Implications of mesenchymal stem cells in regenerative medicine.

    PubMed

    Kariminekoo, Saber; Movassaghpour, Aliakbar; Rahimzadeh, Amirbahman; Talebi, Mehdi; Shamsasenjan, Karim; Akbarzadeh, Abolfazl

    2016-05-01

    Mesenchymal stem cells (MSCs) are a population of multipotent progenitors which reside in bone marrow, fat, and some other tissues and can be isolated from various adult and fetal tissues. Self-renewal potential and multipotency are MSC's hallmarks. They have the capacity of proliferation and differentiation into a variety of cell lineages like osteoblasts, condrocytes, adipocytes, fibroblasts, cardiomyocytes. MSCs can be identified by expression of some surface molecules like CD73, CD90, CD105, and lack of hematopoietic specific markers including CD34, CD45, and HLA-DR. They are hopeful tools for regenerative medicine for repairing injured tissues. Many studies have focused on two significant features of MSC therapy: (I) systemically administered MSCs home to sites of ischemia or injury, and (II) MSCs can modulate T-cell-mediated immunological responses. MSCs express chemokine receptors and ligands involved in cells migration and homing process. MSCs induce immunomedulatory effects on the innate (dendritic cells, monocyte, natural killer cells, and neutrophils) and the adaptive immune system cells (T helper-1, cytotoxic T lymphocyte, and B lymphocyte) by secreting soluble factors like TGF-β, IL-10, IDO, PGE-2, sHLA-G5, or by cell-cell interaction. In this review, we discuss the main applications of mesenchymal stem in Regenerative Medicine and known mechanisms of homing and Immunomodulation of MSCs.

  14. Stem cells, growth factors and scaffolds in craniofacial regenerative medicine

    PubMed Central

    Tollemar, Viktor; Collier, Zach J.; Mohammed, Maryam K.; Lee, Michael J.; Ameer, Guillermo A.; Reid, Russell R.

    2015-01-01

    Current reconstructive approaches to large craniofacial skeletal defects are often complicated and challenging. Critical-sized defects are unable to heal via natural regenerative processes and require surgical intervention, traditionally involving autologous bone (mainly in the form of nonvascularized grafts) or alloplasts. Autologous bone grafts remain the gold standard of care in spite of the associated risk of donor site morbidity. Tissue engineering approaches represent a promising alternative that would serve to facilitate bone regeneration even in large craniofacial skeletal defects. This strategy has been tested in a myriad of iterations by utilizing a variety of osteoconductive scaffold materials, osteoblastic stem cells, as well as osteoinductive growth factors and small molecules. One of the major challenges facing tissue engineers is creating a scaffold fulfilling the properties necessary for controlled bone regeneration. These properties include osteoconduction, osetoinduction, biocompatibility, biodegradability, vascularization, and progenitor cell retention. This review will provide an overview of how optimization of the aforementioned scaffold parameters facilitates bone regenerative capabilities as well as a discussion of common osteoconductive scaffold materials. PMID:27239485

  15. Renal stem cell reprogramming: Prospects in regenerative medicine

    PubMed Central

    Morales, Elvin E; Wingert, Rebecca A

    2014-01-01

    Stem cell therapy is a promising future enterprise for renal replacement in patients with acute and chronic kidney disease, conditions which affect millions worldwide and currently require patients to undergo lifelong medical treatments through dialysis and/or organ transplant. Reprogramming differentiated renal cells harvested from the patient back into a pluripotent state would decrease the risk of tissue rejection and provide a virtually unlimited supply of cells for regenerative medicine treatments, making it an exciting area of current research in nephrology. Among the major hurdles that need to be overcome before stem cell therapy for the kidney can be applied in a clinical setting are ensuring the fidelity and relative safety of the reprogrammed cells, as well as achieving feasible efficiency in the reprogramming processes that are utilized. Further, improved knowledge about the genetic control of renal lineage development is vital to identifying predictable and efficient reprogramming approaches, such as the expression of key modulators or the regulation of gene activity through small molecule mimetics. Here, we discuss several recent advances in induced pluripotent stem cell technologies. We also explore strategies that have been successful in renal progenitor generation, and explore what these methods might mean for the development of cell-based regenerative therapies for kidney disease. PMID:25258667

  16. Amniotic fluid-derived stem cells in regenerative medicine research.

    PubMed

    Joo, Sunyoung; Ko, In Kap; Atala, Anthony; Yoo, James J; Lee, Sang Jin

    2012-02-01

    The stem cells isolated from amniotic fluid present an exciting possible contribution to the field of regenerative medicine and amniotic fluid-derived stem (AFS) cells have significant potential for research and therapeutic applications. AFS cells are multipotent, showing the ability to differentiate into cell types from all three embryonic germ layers. They express both embryonic and adult stem cell markers, expand extensively without feeder cells, double in 36 h, and are not tumorigenic. The AFS cells can be maintained for over 250 population doublings and preserve their telomere length and a normal karyotype. They differentiate easily into specific cell lineages and do not require human embryo tissue for their isolation, thus avoiding the current controversies associated with the use of human embryonic stem (ES) cells. The discovery of the AFS cells has been recent, and a great deal of work remains to be performed on the characterization and use of these cells. This review describes the various differentiated lineages that AFS cells can form and the future of these promising new stem cells in regenerative medicine research.

  17. Unitized Regenerative Fuel Cell System Gas Storage-Radiator Development

    NASA Technical Reports Server (NTRS)

    Burke, Kenneth A.; Jakupta, Ian

    2005-01-01

    High-energy-density regenerative fuel cell systems that are used for energy storage require novel approaches to integrating components in order to preserve mass and volume. A lightweight unitized regenerative fuel cell (URFC) energy storage system concept is being developed at the NASA Glenn Research Center. This URFC system minimizes mass by using the surface area of the hydrogen and oxygen storage tanks as radiating heat surfaces for overall thermal control of the system. The waste heat generated by the URFC stack during charging and discharging is transferred from the cell stack to the surface of each tank by loop heat pipes, which are coiled around each tank and covered with a thin layer of thermally conductive carbon composite. The thin layer of carbon composite acts as a fin structure that spreads the heat away from the heat pipe and across the entire tank surface. Two different-sized commercial-grade composite tanks were constructed with integral heat pipes and tested in a thermal vacuum chamber to examine the feasibility of using the storage tanks as system radiators. The storage tank-radiators were subjected to different steady-state heat loads and varying heat load profiles. The surface emissivity and specific heat capacity of each tank were calculated. In the future, the results will be incorporated into a model that simulates the performance of similar radiators using lightweight, spacerated carbon composite tanks.

  18. High Energy Density Regenerative Fuel Cell Systems for Terrestrial Applications

    NASA Technical Reports Server (NTRS)

    Burke, Kenneth A.

    1999-01-01

    Regenerative Fuel Cell System (RFCS) technology for energy storage has been a NASA power system concept for many years. Compared to battery-based energy storage systems, RFCS has received relatively little attention or resources for development because the energy density and electrical efficiency were not sufficiently attractive relative to advanced battery systems. Even today, RFCS remains at a very low technology readiness level (TRL of about 2 indicating feasibility has been demonstrated). Commercial development of the Proton Exchange Membrane (PEM) fuel cells for automobiles and other terrestrial applications and improvements in lightweight pressure vessel design to reduce weight and improve performance make possible a high energy density RFCS energy storage system. The results from this study of a lightweight RFCS energy storage system for a remotely piloted, solar-powered, high altitude aircraft indicate an energy density up to 790 w-h/kg with electrical efficiency of 53.4% is attainable. Such an energy storage system would allow a solar-powered aircraft to carry hundreds of kilograms of payload and remain in flight indefinitely for use in atmospheric research, earth observation, resource mapping. and telecommunications. Future developments in the areas of hydrogen and oxygen storage, pressure vessel design, higher temperature and higher- pressure fuel cell operation, unitized regenerative fuel cells, and commercial development of fuel cell technology will improve both the energy density and electrical efficiency of the RFCS.

  19. Regenerative Medicine for Periodontal and Peri-implant Diseases.

    PubMed

    Larsson, L; Decker, A M; Nibali, L; Pilipchuk, S P; Berglundh, T; Giannobile, W V

    2016-03-01

    The balance between bone resorption and bone formation is vital for maintenance and regeneration of alveolar bone and supporting structures around teeth and dental implants. Tissue regeneration in the oral cavity is regulated by multiple cell types, signaling mechanisms, and matrix interactions. A goal for periodontal tissue engineering/regenerative medicine is to restore oral soft and hard tissues through cell, scaffold, and/or signaling approaches to functional and aesthetic oral tissues. Bony defects in the oral cavity can vary significantly, ranging from smaller intrabony lesions resulting from periodontal or peri-implant diseases to large osseous defects that extend through the jaws as a result of trauma, tumor resection, or congenital defects. The disparity in size and location of these alveolar defects is compounded further by patient-specific and environmental factors that contribute to the challenges in periodontal regeneration, peri-implant tissue regeneration, and alveolar ridge reconstruction. Efforts have been made over the last few decades to produce reliable and predictable methods to stimulate bone regeneration in alveolar bone defects. Tissue engineering/regenerative medicine provide new avenues to enhance tissue regeneration by introducing bioactive models or constructing patient-specific substitutes. This review presents an overview of therapies (e.g., protein, gene, and cell based) and biomaterials (e.g., resorbable, nonresorbable, and 3-dimensionally printed) used for alveolar bone engineering around teeth and implants and for implant site development, with emphasis on most recent findings and future directions.

  20. Gaussian-only regenerative stations cannot act as quantum repeaters

    NASA Astrophysics Data System (ADS)

    Namiki, Ryo; Gittsovich, Oleg; Guha, Saikat; Lütkenhaus, Norbert

    2014-12-01

    Higher transmission loss diminishes the performance of optical communication—be it the rate at which classical or quantum data can be sent reliably, or the secure key generation rate of quantum key distribution (QKD). Loss compounds with distance—exponentially in an optical fiber, and inverse square with distance for a free-space channel. In order to boost classical communication rates over long distances, it is customary to introduce regenerative relays at intermediate points along the channel. It is therefore natural to speculate whether untended regenerative stations, such as phase-insensitive or phase-sensitive optical amplifiers, could serve as repeaters for long-distance QKD. The primary result of this paper rules out all bosonic Gaussian channels to be useful as QKD repeaters, which include phase-insensitive and phase-sensitive amplifiers as special cases, for any QKD protocol. We also delineate the conditions under which a Gaussian relay renders a lossy channel entanglement breaking, which in turn makes the channel useless for QKD.