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2.
Odontology ; 106(4): 469-480, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29713913

RESUMO

Antiresorptive-related osteonecrosis of the jaw (ARONJ) is a rare but severe side effect of antiresorptive treatment with bisphosphonates or RANKL-antibody denosumab in patients with malignant diseases or osteoporosis. Whilst osteonecrosis of the jaw (ONJ) related to the administration of bisphosphonates (BPs) has been investigated for more than 1 decade now, only few data are available on denosumab-related ONJ, especially in patients with osteoporosis. From 2008 to 2016, 52 osteoporosis patients were treated with ARONJ in the Department of Oral and Maxillofacial Surgery, University Medical Center Freiburg, Germany. In all patients, a surgical regimen consisting of complete removal of necrotic bone, primary wound closure and perioperative i.v. antibiotic therapy was applied. Of the 52 patients, 38 developed ARONJ after BP monotherapy; in 11 patients, antiresorptive therapy had been transitioned from BPs to denosumab and 3 patients had received denosumab monotherapy. From July 2013, when the first patient with ONJ and transitioning therapy from BPs to denosumab presented to our department, to October 2016, we found recurrences in 17.6% of the patients with BP monotherapy and in 45.5% of the patients with transitioning therapy from BPs to denosumab. Transitioning antiresorptive therapy from BPs to denosumab may be an additional risk factor for developing ARONJ. In these patients, treatment of ARONJ-lesions seems to provoke more complications. An additional dental screening before transitioning should be initiated. Further studies are needed to evaluate if a first-line treatment with denosumab decreases the incidence of ARONJ in patients with osteoporosis and simplifies its treatment.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/terapia , Conservadores da Densidade Óssea/efeitos adversos , Denosumab/efeitos adversos , Osteoporose/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Panorâmica , Resultado do Tratamento
3.
Phys Rev Lett ; 116(12): 122502, 2016 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-27058074

RESUMO

The lifetimes of the first excited 2^{+} and 4^{+} states in ^{72}Ni were measured at the National Superconducting Cyclotron Laboratory with the recoil-distance Doppler-shift method, a model-independent probe to obtain the reduced transition probability. Excited states in ^{72}Ni were populated by the one-proton knockout reaction of an intermediate energy ^{73}Cu beam. γ-ray-recoil coincidences were detected with the γ-ray tracking array GRETINA and the S800 spectrograph. Our results provide evidence of enhanced transition probability B(E2;2^{+}→0^{+}) as compared to ^{68}Ni, but do not confirm the trend of large B(E2) values reported in the neighboring isotope ^{70}Ni obtained from Coulomb excitation measurement. The results are compared to shell model calculations. The lifetime obtained for the excited 4_{1}^{+} state is consistent with models showing decay of a seniority ν=4, 4^{+} state, which is consistent with the disappearance of the 8^{+} isomer in ^{72}Ni.

4.
Nanotechnology ; 27(11): 115602, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26878255

RESUMO

We report nano-selective area growth (NSAG) of BGaN by MOCVD on AlN/Si(111) and GaN templates resulting in 150 nm single crystalline nanopyramids. This is in contrast to unmasked or micro-selective area growth, which results in a multi-crystalline structure on both substrates. Various characterization techniques were used to evaluate NSAG as a viable technique to improve BGaN material quality on AlN/Si(111) using results of GaN NSAG and unmasked BGaN growth for comparison. Evaluation of BGaN nanopyramid quality, shape and size uniformity revealed that the growth mechanism is the same on both the templates. Further STEM analysis of BGaN nanopyramids on AlN/Si (111) templates confirmed that these are single-crystalline structures without any dislocations, likely due to single nucleation occurring in the 80 nm mask opening. CL results correspond to boron content between 1.7% and 2.0% in the nanopyramids. We conclude that NSAG is promising for growth of high-quality BGaN nanostructures and complex nano-heterostructures, especially for low-cost silicon substrates.

5.
Phys Rev Lett ; 114(19): 192502, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26024166

RESUMO

The first conclusive evidence of a dipole resonance in ^{11}Li having isoscalar character observed from inelastic scattering with a novel solid deuteron target is reported. The experiment was performed at the newly commissioned IRIS facility at TRIUMF. The results show a resonance peak at an excitation energy of 1.03±0.03 MeV with a width of 0.51±0.11 MeV (FWHM). The angular distribution is consistent with a dipole excitation in the distorted-wave Born approximation framework. The observed resonance energy together with shell model calculations show the first signature that the monopole tensor interaction is important in ^{11}Li. The first ab initio calculations in the coupled cluster framework are also presented.

6.
J Oral Maxillofac Surg ; 72(1): 128-38, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24095006

RESUMO

PURPOSE: This article presents a novel method of navigation-guided lateral gap arthroplasty (LGA) in the treatment of temporomandibular joint ankylosis (TMJA). MATERIALS AND METHODS: Six patients with unilateral TMJA from 2007 through 2011 were included in this study. Presurgical planning was performed to determine the amount and extent of ankylosed bone to be resected using the simulation platform. Minimum follow-up was 6 months. Patients were monitored for complications and signs of recurrence. Maximum mouth opening (MO) was measured and compared intra- and postoperatively. RESULTS: Preoperative planning was performed at the STN or Accu-Navi workstation. The amount and extent of ankylosed bone to be resected was determined. All 6 LGAs were completed successfully using real-time instrument- and pointer-based navigation. Measurements performed intraoperatively showed that the mean for maximum MO was about 35 to 40 mm and remained the same postoperatively. Follow-up evaluation showed remarkable improvement in function and esthetics, with no signs of recurrence. CONCLUSION: Navigation-guided LGA can be regarded a viable option for performing this delicate and complicated surgical procedure.


Assuntos
Anquilose/cirurgia , Artroplastia/métodos , Cirurgia Assistida por Computador/métodos , Transtornos da Articulação Temporomandibular/cirurgia , Adolescente , Adulto , Pontos de Referência Anatômicos/anatomia & histologia , Anquilose/etiologia , Simulação por Computador , Feminino , Seguimentos , Humanos , Cuidados Intraoperatórios , Masculino , Côndilo Mandibular/lesões , Fraturas Mandibulares/complicações , Modelos Anatômicos , Planejamento de Assistência ao Paciente , Modalidades de Fisioterapia , Complicações Pós-Operatórias , Amplitude de Movimento Articular/fisiologia , Recidiva , Transtornos da Articulação Temporomandibular/etiologia , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Interface Usuário-Computador , Adulto Jovem
7.
Phys Rev Lett ; 108(12): 122501, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-22540576

RESUMO

We present a novel technique for studying the quenching of shell gaps in exotic isotopes. The method is based on extracting Gamow-Teller (ΔL=0, ΔS=1) transition strengths [B(GT)] to low-lying states from charge-exchange reactions at intermediate beam energies. These Gamow-Teller strengths are very sensitive to configuration mixing between cross-shell orbitals, and this technique thus provides an important complement to other tools currently used to study cross-shell mixing. This work focuses on the N=8 shell gap. We populated the ground and 2.24 MeV 0+ states in 12Be using the 12B(1+) (7Li, 7Be) reaction at 80 MeV/u in inverse kinematics. Using the ground-state B(GT) value from ß-decay measurements (0.184±0.007) as a calibration, the B(GT) for the transition to the second 0+ state was determined to be 0.214±0.051. Comparing the extracted Gamow-Teller strengths with shell-model calculations, it was determined that the wave functions of the first and second 0+ states in 12Be are composed of 25±5% and 60±5% (0s)4(0p)8 configurations, respectively.

8.
Nanotechnology ; 23(45): 455707, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23089619

RESUMO

Using elastic scattering theory we show that a small set of energy dispersive x-ray spectroscopy (EDX) measurements is sufficient to experimentally evaluate the scattering function of electrons in high-angle annular dark field scanning transmission microscopy (HAADF-STEM). We then demonstrate how to use this function to transform qualitative HAADF-STEM images of InGaN layers into precise, quantitative chemical maps of the indium composition. The maps obtained in this way combine the resolution of HAADF-STEM and the chemical precision of EDX. We illustrate the potential of such chemical maps by using them to investigate nanometer-scale fluctuations in the indium composition and their impact on the growth of epitaxial InGaN layers.

9.
Osteoporos Int ; 22(4): 1115-21, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20503036

RESUMO

UNLABELLED: Osteoporosis is a major public health problem worldwide. Its significance in the fields of traumatology and implantology of the maxillofacial area requires investigation. A large animal model was used to assess bone loss in the lumbar spine and mandible. INTRODUCTION: Osteoporosis is a prevalent disease characterized by low bone mass and microarchitectural deterioration of bone tissue. Osteoporosis-related fractures represent a major public health burden. The presence and relevance of osteoporosis in the maxillofacial area remain controversial. Research in humans is limited by difficulties in finding large homogenous study groups and, due to ethical considerations, numerous animal models have been used in osteoporosis research. The aim of this study was to assess a sheep model of generalized osteopenia for changes in the maxillofacial area. METHODS: Bone loss was induced in ten Merino sheep by ovariectomy, intramuscular administration of glucocorticoids, and a calcium-reduced diet. Five untreated animals served as controls. Bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry at the lumbar spine at baseline and after 1, 3, 6, 9, and 12 months. Lumbar and mandibular bone biopsies were obtained and analyzed with microcomputed tomography. RESULTS: Lumbar BMD decreased progressively in the intervention group and was most significantly low after 6 months (p < 0.001). Lumbar trabecular bone showed a significant decrease in bone volume (BV)/tissue volume (TV; p < 0.05) in the inducted group. Significant changes were found in both analyzed mandibular regions for BV/TV (p < 0.05). Regional variations were found for other parameters in the mandible. The cortical width was substantially reduced in the intervention group (p < 0.001). CONCLUSIONS: Microstructural changes occurring in sheep as a result of induction seem to have a generalized nature. This sheep model meets the criteria for further investigation in the maxillofacial area.


Assuntos
Doenças Ósseas Metabólicas/etiologia , Modelos Animais de Doenças , Mandíbula/fisiopatologia , Animais , Doenças Ósseas Metabólicas/diagnóstico por imagem , Doenças Ósseas Metabólicas/fisiopatologia , Cálcio da Dieta/administração & dosagem , Dexametasona , Feminino , Glucocorticoides , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiopatologia , Mandíbula/diagnóstico por imagem , Ovariectomia , Ovinos , Microtomografia por Raio-X/métodos
10.
Phys Rev Lett ; 106(2): 022502, 2011 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-21405225

RESUMO

The transition rates for the 2(1)+ states in (62,64,66)Fe were studied using the recoil distance Doppler-shift technique applied to projectile Coulomb excitation reactions. The deduced E2 strengths illustrate the enhanced collectivity of the neutron-rich Fe isotopes up to N = 40. The results are interpreted using the generalized concept of valence proton symmetry which describes the evolution of nuclear structure around N = 40 as governed by the number of valence protons with respect to Z ≈ 30. The trend of collectivity suggested by the experimental data is described by state-of-the-art shell-model calculations with a new effective interaction developed for the fpgd valence space.

11.
Phys Rev Lett ; 107(10): 102501, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21981497

RESUMO

Establishing how and when large N/Z values require modified or new theoretical tools is a major quest in nuclear physics. Here we report the first measurement of the lifetime of the 2(1)+ state in the near-dripline nucleus 20C. The deduced value of τ(2(1)+)=9.8±2.8(stat)(-1.1)(+0.5)(syst) ps gives a reduced transition probability of B(E2; 2(1)+→0(g.s.)+)=7.5(-1.7)(+3.0)(stat)(-0.4)(+1.0)(syst) e2 fm4 in good agreement with a shell model calculation using isospin-dependent effective charges.

12.
Int J Oral Maxillofac Surg ; 50(4): 511-515, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32847710

RESUMO

A 71-year-old woman was referred to the clinic with extensive medication-related osteonecrosis of the jaw (MRONJ) involving the mandible. She had received 7 years of zoledronate therapy. On cone beam computed tomography, the MRONJ presented as a large sequestrum spanning from the left to the right condylar process, surrounded by thick sub-periosteal bone. The sequestrum was excised via an intraoral approach, leaving the newly formed sub-periosteal bone as a neo-mandible. The patient recovered well from the operation and was discharged 5 days after surgery. She healed completely without complications. This case report presents an alternative surgical treatment that may be considered if there is clinically stable sub-periosteal bone surrounding extensive MRONJ.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Conservadores da Densidade Óssea , Osteonecrose , Idoso , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/diagnóstico por imagem , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/cirurgia , Conservadores da Densidade Óssea/efeitos adversos , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Mandíbula , Ácido Zoledrônico
13.
J Oral Biol Craniofac Res ; 11(4): 601-607, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34567964

RESUMO

Skull base surgery remains one of the challenging areas in the field of cranio-maxillofacial surgery, otolaryngology and neurosurgery. Subsequent reconstruction of bone and soft tissue are an essential component to restore function and appearance after ablative surgery. Establishment of interdisciplinary tumor boards with presentation of the individual patient cases have become standard. Multiplanar reconstruction using MRI or CT imaging techniques combined with virtual 3D planning allow precise planning of the procedures. Intraoperative navigation helps for complete resection of malignant findings with safety margins; surgical approaches provide a good overview of the surgical site. Reconstruction using local flaps have a low complication rate with equally reliable results in reconstruction of small tissue defects. Free flap surgery makes reconstruction of large tissue defects possible. Alloplastic materials are alternatively used for reconstruction of bone defects. Based on selected patients, treatment algorithms and standard surgical procedures in extracerebral skull base surgery will be illustrated. Current techniques and new approaches will be discussed with emphasize on hard and soft tissue reconstruction.

14.
Phys Rev Lett ; 104(21): 212504, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20867091

RESUMO

We report on the first successful extraction of a ß+ Gamow-Teller strength distribution from a radioactive isotope in an intermediate-energy charge-exchange experiment in inverse kinematics. The (7Li,7Be+γ(429 keV)) reaction at 100A MeV was used to measure Gamow-Teller transition strengths from 34P to states in 34Si. The results show that little mixing occurs between sd and pf shell configurations for the low-lying 0+ and 2+ states even though 34Si neighbors the island of inversion and low-lying 2ℏω intruder states exist. Shell-model calculations in the sdpf model space are consistent with these findings.

15.
J Stomatol Oral Maxillofac Surg ; 121(5): 599-603, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31904529

RESUMO

Salivary duct carcinoma (SDC) is a rare and highly aggressive neoplasm of the salivary glands associated with high rates of local and distant recurrence and poor overall survival. We present a patient with SDC, who relapsed despite extensive multimodal therapy including surgery, postoperative radiochemotherapy, and heavy ion therapy. In the recurrent setting, immunohistochemical analysis confirmed androgen receptor positivity, prompting initiation of combined androgen deprivation therapy (ADT), which resulted in a fast and durable remission of the local tumor now lasting for 26 months. Analyzing the histopathologic specimens of all SDC patients treated at our department since 2009, we found significant AR expression in all patients. This is in line with other reports found in current literature and indicates AR positivity as a consistent feature of SDC, supporting ADT as a viable therapeutic option for SDC.


Assuntos
Antagonistas de Androgênios , Neoplasias da Próstata , Antagonistas de Androgênios/uso terapêutico , Humanos , Masculino , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/tratamento farmacológico , Receptores Androgênicos/genética , Ductos Salivares
16.
J Cell Biol ; 83(3): 562-75, 1979 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-521454

RESUMO

Treatment of sparse, proliferating cultures of 3T3 cells (target cells) with medium conditioned by exposure to density-inhibited 3T3 cultures resulted in an inhibition of growth and division in the target cells when compared to similar treatment with unconditioned medium (UCM). This differential effect of conditioned medium (CM) and UCM on target cells was demonstrated using three assay systems: (a) assessment of total cell number; (b) measurement of [3H]thymidine incorporated into acid-precipitable DNA; and (c) determination of the percentage of radioactively labeled nuclei in individual cells after incorporation of [3H]thymidine. The difference in the total incorporation of [3H]thymidine in CM-treated and UCM-treated cells was reflected by a difference in the percent of labeled cells. There was no differences in the average number of grains per labeled cell in the two cultures. Moreover, the inhibitory effect of the CM on target cell proliferation was reversible. Finally, this growth inhibitory activity can be collected in serum-free medium, precipitated by ammonium sulfate, and fractionated by gel filtration. In these purification procedures, the inhibitory activity was consistently found to be associated with the protein-containing fractions of the CM. No activity was found upon similar treatment with UCM. These results suggest that a system has been developed for the purification and molecular analysis of growth inhibitory factors that may mediate growth control in culture fibroblasts.


Assuntos
Divisão Celular/efeitos dos fármacos , Inibidores do Crescimento/farmacologia , Animais , Contagem de Células , Linhagem Celular , Sobrevivência Celular , Meios de Cultura/análise , DNA/biossíntese , Fibroblastos , Camundongos , Timidina/metabolismo
17.
J Cell Biol ; 92(2): 523-30, 1982 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7061594

RESUMO

Treatment of sparse, proliferating cultures of 3T3 cells with medium conditioned by exposure to density-inhibited 3T3 cultures resulted in an inhibition of growth and division in the target cells when compared to similar treatment with unconditioned medium. This growth inhibitory activity was fractionated by ammonium sulfate precipitation and gel filtration, yielding one fraction that was 35-fold enriched in specific activity. Analysis of the chemical and biological properties of this highly active fraction indicated that: (a) it is an endogenous cell product, synthesized by the 3T3 cells and shed into the medium; (b) it is a protein and its activity is sensitive to treatment with pronase; (c) the constituent polypeptide chains have molecular weights of 10,000 and 13,000; and (d) it is not cytotoxic and its effect on target cells are reversible. These results suggest that we have partially purified from conditioned medium an endogenous growth regulatory factor that may play a role in density-dependent inhibition of growth in cultured fibroblasts. We propose the term Fibroblast Growth Regulator to describe this class of molecules.


Assuntos
Ciclo Celular , Inibição de Contato , Fibroblastos/fisiologia , Glicopeptídeos/farmacologia , Inibidores do Crescimento/isolamento & purificação , Animais , Células Cultivadas , Meios de Cultura/análise , Replicação do DNA/efeitos dos fármacos , Inibidores do Crescimento/farmacologia , Camundongos , Peso Molecular
19.
Gesundheitswesen ; 71(8-9): 460-8, 2009 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-19418426

RESUMO

AIMS: The aim of the study is the development of a questionnaire for the assessment of health care from the patients' perspective. METHODS: In the framework of a bottom-up approach, 8 focus groups of patients with diabetes or cardiovascular diseases from two different regions have been conducted. Results of the focus groups have been analysed by means of qualitative content analysis. On the basis of the results of the qualitative content analysis, a pool of 125 questions has been developed which constitute the starting point of a stepwise process for the selection of 44 items for a field test questionnaire. The field test questionnaire has been completed by 195 patients from three regions. The dimensional structure and the psychometric properties of the questionnaire have been analysed by means of exploratory and confirmatory factor analyses and by means of item-response-theory (IRT) models. RESULTS: The final questionnaire consists of 18 items belonging to the five dimensions "physician treatment", "treatment equity", "consultation by pharmacists", "preventive care" and "waiting times". The results of the confirmatory factor analysis reveal a good fit of the five factor model. Results of IRT analyses confirm that all subscales have at least an ordinal scale level. The reliability of the five subscales ranges between 0.70 and 0.91. CONCLUSIONS: A questionnaire for the assessment of health care from the patients' perspective has been developed. The new instrument can be applied in the evaluation of interventions for the improvement of the organisational aspects of health care for patients with chronic conditions.


Assuntos
Atitude , Prestação Integrada de Cuidados de Saúde/estatística & dados numéricos , Satisfação do Paciente/estatística & dados numéricos , Garantia da Qualidade dos Cuidados de Saúde/métodos , Inquéritos e Questionários , Alemanha , Humanos
20.
J Craniomaxillofac Surg ; 47(12): 1973-1979, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31810844

RESUMO

The Cook-Swartz-Doppler probe is an easy to handle and reliable tool for free flap monitoring. In the head and neck region different confounders can affect the read out. We therefore analyzed the use of the Doppler probe regarding these potential difficulties and to compare the diagnostic accuracy in arterial or venous monitoring of free flaps in the head and neck region. A retrospective study was performed in which all patients were included who underwent free flap surgery in the head and neck region in the Department of Plastic Surgery and the Department of Maxillofacial Surgery of our institution between 2010 and 2018 and were monitored with an implanted Doppler probe. 147 free tissue transfers were included. No significance was found for arterial and venous placement of the Doppler probe for sensitivity (artery 83.3%; vein 84.6%; p = 0.87), specificity (artery 89.2%; vein 96.1%; p = 0.17) and negative predictive value (artery 96.7%; vein 94.2%; p = 0.55). A better positive predictive value for placing the Doppler probe around the artery (82.7%) than the vein (61.1%) was found in our study (p = 0.056). The better positive predictive value in arterial monitoring suggests that this is the more reliable measuring method to assess flap perfusion in the head and neck region.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Retalhos de Tecido Biológico , Neoplasias de Cabeça e Pescoço/cirurgia , Monitorização Ambulatorial/métodos , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/irrigação sanguínea , Adulto , Idoso , Idoso de 80 Anos ou mais , Retalhos de Tecido Biológico/irrigação sanguínea , Retalhos de Tecido Biológico/fisiologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Fluxometria por Laser-Doppler/instrumentação , Microcirurgia/métodos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/cirurgia , Estudos Retrospectivos
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