168 research outputs found
522 GENE EXPRESSION CHANGES ASSOCIATED WITH CHONDROGENIC DIFFERENTIATION OF HUMAN MSCS J.F. Welter
Two-subband system in quantizing magnetic field: Probing many-body gap by non-equilibrium phonons
We study the many-body effects in a two-subband quasi-two-dimensional
electron system in a quantizing magnetic field at filling factor three. A
manifestation of these effects in the phonon absorption spectroscopy is
discussed. The electron system is mapped onto a two-level system with the
separation between levels determined by the intersubband splitting and the
cyclotron energy. The electron-electron interaction enhances the excitation
gap, which exists at all values of the interlevel splitting. This results in a
single-peak structure of the phonon absorption rate as a function of magnetic
field, instead of the double-peak structure for non-interacting electrons.Comment: 9 pages, 3 figure
Tissue Formation and Vascularization in Anatomically Shaped Human Joint Condyle Ectopically in Vivo
Scale-up of bioengineered grafts toward clinical applications is a challenge in regenerative medicine. Here, we report tissue formation and vascularization of anatomically shaped human tibial condyles ectopically with a dimension of 20 15 15mm3. A composite of poly-ɛ-caprolactone and hydroxyapatite was fabricated using layer deposition of three-dimensional interlaid strands with interconnecting microchannels (400μm) and seeded with human bone marrow stem cells (hMSCs) with or without osteogenic differentiation. An overlaying layer (1mm deep) of poly(ethylene glycol)-based hydrogel encapsulating hMSCs or hMSC-derived chondrocytes was molded into anatomic shape and anchored into microchannels by gel infusion. After 6 weeks of subcutaneous implantation in athymic rats, hMSCs generated not only significantly more blood vessels, but also significantly larger-diameter vessels than hMSC-derived osteoblasts, although hMSC-derived osteoblasts yielded mineralized tissue in microchannels. Chondrocytes in safranin-O-positive glycosaminoglycan matrix were present in the cartilage layer seeded with hMSC-derived chondrogenic cells, although significantly more cells were present in the cartilage layer seeded with hMSCs than hMSC-derived chondrocytes. Together, MSCs elaborate substantially more angiogenesis, whereas their progenies yield corresponding differentiated tissue phenotypes. Scale up is probable by incorporating a combination of stem cells and their progenies in repeating modules of internal microchannels.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78100/1/ten.tea.2008.0653.pd
Elastomeric Osteoconductive Synthetic Scaffolds with Acquired Osteoinductivity Expedite the Repair of Critical Femoral Defects in Rats
Regenerative medicine aspires to reduce reliance on or overcome limitations associated with donor tissue-mediated repair. Structural bone allografts are commonly used in orthopedic surgery, with a high percentage of graft failure due to poor tissue integration. This problem is aggravated among elderly, those suffering from metabolic conditions, or those undergoing cancer therapies that compromise graft healing. Toward this end, we developed a synthetic graft named FlexBone, in which nanocrystalline hydroxyapatite (50-wt%) was structurally integrated with crosslinked poly(hydroxyethyl methacrylate) hydrogel, which provides dimensional stability and elasticity. It recapitulates the essential role of nanocrystalline hydroxyapatite in defining the osteoconductivity and biochemical microenvironment of bone because of its affinity for biomolecules. Here, we demonstrate that FlexBone effectively absorbed endogenously secreted signaling molecules associated with the inflammation/graft healing cascade upon being press-fit into a 5-mm rat femoral segmental defect. Further, when preabsorbed with a single dose of 400-ng recombinant human (rh) bone morphogenetic protein-2/7 heterodimer, it enabled the functional repair of the critical-sized defect by 8-12 weeks. FlexBone was stably encapsulated by the bridging bony callus and the FlexBone-callus interface was continuously remodeled. In summary, FlexBone combines the dimensional stability and osteoconductivity of structural bone allografts with desirable surgical compressibility and acquired osteoinductivity in an easy-to-fabricate and scalable synthetic biomaterial.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90480/1/ten-2Etea-2E2010-2E0274.pd
Описание клинических случаев меланомы кожи
Skin melanoma is a malignant tumor originating in the cells of the melanocytic system, which is characterized by an aggressive clinical course, significant metastatic potential and unfavorable prognosis. These features of the tumor stipulate the need to improve measures to optimize early diagnosis of tumors. The article presents cases of pigmented skin melanoma to demonstrate the variability of clinical manifestations of this tumor requiring dermatologist skills in the differential diagnostics of neoplasms.Меланома кожи - злокачественное новообразование, происходящее из клеток меланоцитарной системы, характеризуется агрессивным клиническим течением, значительным метастатическим потенциалом, неблагоприятным прогнозом. Данные особенности опухоли указывают на необходимость совершенствования мер по оптимизации ранней диагностики новообразования. Описаны случаи пигментной меланомы кожи с целью демонстрации вариабельности клинических проявлений данного новообразования, требующих от врача-дерматолога навыков его дифференциальной диагностики
Colliders and Cosmology
Dark matter in variations of constrained minimal supersymmetric standard
models will be discussed. Particular attention will be given to the comparison
between accelerator and direct detection constraints.Comment: Submitted for the SUSY07 proceedings, 15 pages, LaTex, 26 eps figure
Neonatal intervention
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68335/2/10.1177_027112148300300105.pd
Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV
A search for a Higgs boson decaying into two photons is described. The
analysis is performed using a dataset recorded by the CMS experiment at the LHC
from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an
integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross
section of the standard model Higgs boson decaying to two photons. The expected
exclusion limit at 95% confidence level is between 1.4 and 2.4 times the
standard model cross section in the mass range between 110 and 150 GeV. The
analysis of the data excludes, at 95% confidence level, the standard model
Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The
largest excess of events above the expected standard model background is
observed for a Higgs boson mass hypothesis of 124 GeV with a local significance
of 3.1 sigma. The global significance of observing an excess with a local
significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is
estimated to be 1.8 sigma. More data are required to ascertain the origin of
this excess.Comment: Submitted to Physics Letters
Measurement of isolated photon production in pp and PbPb collisions at sqrt(sNN) = 2.76 TeV
Isolated photon production is measured in proton-proton and lead-lead
collisions at nucleon-nucleon centre-of-mass energies of 2.76 TeV in the
pseudorapidity range |eta|<1.44 and transverse energies ET between 20 and 80
GeV with the CMS detector at the LHC. The measured ET spectra are found to be
in good agreement with next-to-leading-order perturbative QCD predictions. The
ratio of PbPb to pp isolated photon ET-differential yields, scaled by the
number of incoherent nucleon-nucleon collisions, is consistent with unity for
all PbPb reaction centralities.Comment: Submitted to Physics Letters
Níveis críticos e tóxicos de boro em solos de Pernambuco determinados em casa de vegetação
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