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1.
Radiologe ; 61(12): 1107-1114, 2021 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-34767032

RESUMO

BACKGROUND: Due to our ageing population, the number of elderly patients who are treated in the emergency department due to low-energy trauma (e.g., tripping) continues to rise. These minor accidents often result in fragility fractures classically located in the proximal humerus, distal radius, spine, pelvis, and near the hip joint. Pre-existing conditions, polypharmacy, and general frailty increase the risk of fragility fractures in this patient population. METHODS: Geriatric trauma fractures and especially insufficiency fractures of the posterior pelvic ring are often difficult to diagnose by plain X­ray. Therefore, in geriatric trauma patients, cross-sectional imaging, e.g., computed tomography (CT), dual-energy CT (DECT), or magnetic resonance imaging (MRI), should be considered early for reliable evaluation of a suspected fracture. This also allows for the identification of older fractures. Particularly in cognitively impaired elderly patients, difficult examination conditions or an unclear fall event, cross-sectional imaging is often indicated. However, this may also involve risks, e.g., use of contrast medium in patients with impaired renal function, so that each case must be considered individually. Furthermore, the diagnosis and treatment of osteoporosis, which is an underlying disease that leads to fragility fractures, is of particular importance. In the diagnostic workup, measurement of bone density using dual energy X­ray absorptiometry (DXA) is the standard method according to guidelines. In specific situations, high-resolution peripheral quantitative CT (HR-pQCT) may also be used. CONCLUSION: Due to the special challenges of correctly detecting fragility fractures and being able to quickly initiate adequate therapy, good cooperation between radiologists and trauma surgeons is necessary.


Assuntos
Fraturas Ósseas , Osteoporose , Absorciometria de Fóton , Idoso , Densidade Óssea , Humanos , Tomografia Computadorizada por Raios X
2.
Z Gerontol Geriatr ; 52(5): 414-420, 2019 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-31297588

RESUMO

The differential diagnoses of osteoporosis in geriatric and trauma patients are very important as they may induce different therapies. On average approximately 20% of women and 50% of men have secondary causes of osteoporosis. The foundation of the diagnostics is a basic osteological laboratory investigation with which the most important secondary causes can be identified. From a geriatric and traumatological point of view vitamin D deficiency with secondary hyperparathyroidism, primary hyperparathyroidism, male hypogonadism, multiple myeloma and monoclonal gammopathy of unclear significance (MGUS) are of particular importance.


Assuntos
Gamopatia Monoclonal de Significância Indeterminada/complicações , Mieloma Múltiplo/complicações , Osteoporose/diagnóstico , Deficiência de Vitamina D/complicações , Idoso , Diagnóstico Diferencial , Feminino , Geriatria , Humanos , Masculino , Deficiência de Vitamina D/sangue
3.
Osteoporos Int ; 28(11): 3215-3228, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28849275

RESUMO

To better understand the association between high salt intake and osteoporosis, we investigated the effect of sodium chloride (NaCl) on mice and human osteoclastogenesis. The results suggest a direct, activating role of NaCl supplementation on bone resorption. INTRODUCTION: High NaCl intake is associated with increased urinary calcium elimination and parathyroid hormone (PTH) secretion which in turn stimulates the release of calcium from the bone, resulting in increased bone resorption. However, while calciuria after NaCl loading could be shown repeatedly, several studies failed to reveal a significant increase in PTH in response to a high-sodium diet. Another possible explanation that we investigated here could be a direct effect of high-sodium concentration on bone resorption. METHODS: Mouse bone marrow macrophage and human peripheral blood mononuclear cells (PBMC) driven towards an osteoclastogenesis pathway were cultivated under culture conditions mimicking hypernatremia environments. RESULTS: In this study, a direct effect of increased NaCl concentrations on mouse osteoclast differentiation and function was observed. Surprisingly, in a human osteoclast culture system, significant increases in the number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts, calcitonin receptor (CTR)-positive osteoclasts, nuclear factor-activated T cells c1 (NFATc1) gene expression, and areal and volumetric resorptions were observed for increasing concentrations of NaCl. This suggests a direct, activating, cell-mediated effect of increased concentrations of NaCl on osteoclasts. CONCLUSIONS: The reported that enhanced bone resorption after high-sodium diets may not only be secondary to the urinary calcium loss but may also be a direct, cell-mediated effect on osteoclastic resorption. These findings allow us to suggest an explanation for the clinical findings independent of a PTH-mediated regulation.


Assuntos
Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Animais , Reabsorção Óssea/induzido quimicamente , Reabsorção Óssea/metabolismo , Reabsorção Óssea/fisiopatologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Camundongos , Osteoclastos/citologia , Osteoclastos/metabolismo , Receptores da Calcitonina/metabolismo , Cloreto de Sódio/administração & dosagem , Fosfatase Ácida Resistente a Tartarato/metabolismo
4.
Appl Opt ; 56(19): G188-G196, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29047484

RESUMO

We report a phenomenon manifesting itself as brief flashes of light on the snow's surface near a lidar beam. The flashes are imaged and interpreted as specular reflection patterns from individual ice particles. Such patterns have a two-dimensional structure and are similar to those previously observed in forward scattering. Patterns are easiest to capture from particles with well-defined horizontal facets, such as near-horizontally aligned plates. The patterns and their position can be used to determine properties such as ice particle shape, size, roughness, alignment, and altitude. Data obtained at Summit in Greenland show the presence of regular hexagonal and scalene plates, columns, and rounded plates of various sizes, among others.

5.
J Evol Biol ; 28(9): 1682-90, 2015 09.
Artigo em Inglês | MEDLINE | ID: mdl-26135011

RESUMO

Abiotic environmental heterogeneity can promote the evolution of diverse resource specialists, which in turn may increase the degree of host-parasite specialization. We coevolved Pseudomonas fluorescens and lytic phage ϕ2 in spatially structured populations, each consisting of two interconnected subpopulations evolving in the same or different nutrient media (homogeneous and heterogeneous environments, respectively). Counter to the normal expectation, host-parasite specialization was significantly lower in heterogeneous compared with homogeneous environments. This result could not be explained by dispersal homogenizing populations, as this would have resulted in the heterogeneous treatments having levels of specialization equal to or greater than that of the homogeneous environments. We argue that selection for costly generalists is greatest when the coevolving species are exposed to diverse environmental conditions and that this can provide an explanation for our results. A simple coevolutionary model of this process suggests that this can be a general mechanism by which environmental heterogeneity can reduce rather than increase host-parasite specialization.


Assuntos
Interações Hospedeiro-Parasita , Modelos Teóricos , Fagos de Pseudomonas/fisiologia , Pseudomonas fluorescens/virologia , Evolução Biológica , Fagos de Pseudomonas/genética , Pseudomonas fluorescens/genética , Seleção Genética
8.
Science ; 232(4749): 497-9, 1986 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-3961492

RESUMO

Dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin, TCDD) is a highly toxic contaminant produced in the manufacture of phenoxy herbicides. Despite its high TCDD content, soil from a contaminated area associated with a 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) manufacturing site in Newark, New Jersey, did not induce acute toxicity when administered to guinea pigs (the most sensitive species) by gavage. Analysis of liver samples demonstrated low bioavailability of TCDD from this soil. A comparative analysis of soils showed that Soxhlet extraction was necessary for the determination of TCDD on Newark soil, whereas solvent extraction was sufficient for soil from Times Beach, Missouri. The difference in the bioavailability of TCDD from these soils is correlated with TCDD extractability and may be related to the different compositions of the soils.


Assuntos
Ácido 2,4,5-Triclorofenoxiacético/síntese química , Indústria Química , Dioxinas/metabolismo , Dibenzodioxinas Policloradas/metabolismo , Poluentes do Solo , Animais , Benzofuranos/análise , Disponibilidade Biológica , Dioxinas/análise , Feminino , Cobaias , Masculino , New Jersey , Dibenzodioxinas Policloradas/análise , Dibenzodioxinas Policloradas/toxicidade , Solo/análise , Poluentes do Solo/análise
9.
Pharmacoepidemiol Drug Saf ; 18(11): 1101-10, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19688727

RESUMO

PURPOSE: In the majority of studies on determinants of use of anxiolytics and antidepressants a substantially higher consumption is observed among women than among men. We investigated gender differences in the association between the use of anxiolytics and antidepressants and mental health and explored if there are indications of gender differences in inappropriate use of these medicines. METHODS: Data were from the 2004 Belgian Health Interview Survey, a nationally representative sample of the Belgian population. The analysis was restricted to the population of 15 years and older (n = 11,220). The probability of use of anxiolytics and antidepressants was assessed through logistic regression models by gender and through models including the interaction between gender and mental health. RESULTS: The association between the use of antidepressants and mental health did not vary substantially between men and women. Among men the use of anxiolytics showed a strong association with sleeping problems, but not with depressive disorders. Among women the use of anxiolytics was significantly associated with the three mental health conditions that were investigated: depressive disorder, anxiety, and sleeping problems. CONCLUSIONS: The link between mental health and use of anxiolytics differs by gender. Some indications exist for gender differences in inappropriate use of anxiolytics, whereas this does not hold true for the use of antidepressants. Further efforts are needed to increase the awareness of prescribers, policy makers, and the general public on the appropriate use of anxiolytics, especially among women and in the older population.


Assuntos
Ansiolíticos/administração & dosagem , Antidepressivos/administração & dosagem , Revisão de Uso de Medicamentos , Saúde Mental , Vigilância da População , Caracteres Sexuais , Adolescente , Adulto , Idoso , Bélgica , Feminino , Humanos , Modelos Logísticos , Masculino , Saúde Mental/estatística & dados numéricos , Pessoa de Meia-Idade , Adulto Jovem
10.
J Biomech ; 41(9): 1885-91, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18495131

RESUMO

Until now, there has been no in vitro model that duplicates the environment of bone marrow. The purpose of this study was to analyze proliferation and differentiation of human bone marrow stromal cells (hBMSC) under the influence of continuous perfusion and cyclic mechanical loading. hBMSC of seven individuals were harvested, grown in vitro, and combined. 10(6) hBMSC were seeded on a bovine spongiosa disc and incubated in a bioreactor system. Cell culture was continued using three different conditions: Continuous perfusion (group A), 10% cyclic compression at 0.5Hz (group B) and static controls (group C). After 24h, 1, 2, and 3 weeks, we determined cell proliferation (MTS-assay) and osteogenic differentiation (osteocalcin ELISA, Runx2 mRNA). Tenascin-C mRNA was quantified to exclude fibroblastic differentiation. In groups A and B, proliferation was enhanced after 2 weeks (48.6+/-19.6x10(3) (A) and 44.6+/-14.3 x 10(3) cells (B)) and after 3 weeks (46.6+/-15.1 x 10(3) (A) and 44.8+/-10.2 x 10(3) cells (B)) compared with controls (26.3+/-10.8 x 10(3) (2 weeks) and 17.1+/-6.5 x 10(3) cells (3 weeks), p<0.03). Runx2 mRNA was upregulated in both stimulated groups after 1, 2, and 3 weeks compared to control (group A, 1 week: 5.2+/-0.7-fold; p<0.01, 2 weeks: 4.4+/-1.9-fold; p<0.01, 3 weeks: 3.8+/-1.7-fold; p=0.013; group B, 1 week: 3.6+/-1.1-fold, p<0.01, 2 weeks: 4.2+/-2.2-fold, p<0.01; 3 weeks: 5.3+/-2.7-fold, p<0.01). hBMSC stimulated by cyclic compression expressed the highest amount of osteocalcin at all time points (1 week: 294.5+/-88.4 mg/g protein, 2 weeks: 294.4+/-73.3mg/g protein, 3 weeks: 293.1+/-83.6 mg/g protein, p0.03). The main stimulus for cell proliferation in a 3-dimensional culture of hBMSC is continuous perfusion whereas mechanical stimulation fosters osteogenic commitment of hBMSC. This study thereby contributes to the understanding of physical stimuli that influence hBMSC in a 3-dimensional cell culture system.


Assuntos
Células da Medula Óssea/citologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Células da Medula Óssea/metabolismo , Proliferação de Células , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Ciclização , Regulação da Expressão Gênica , Humanos , Osteocalcina/metabolismo , RNA Mensageiro/genética , Células Estromais/citologia , Células Estromais/metabolismo
11.
Mar Pollut Bull ; 95(1): 248-52, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25916197

RESUMO

Marine filter feeders are exposed to microplastic because of their selection of small particles as food source. Baleen whales feed by filtering small particles from large water volumes. Macroplastic was found in baleen whales before. This study is the first to show the presence of microplastic in intestines of a baleen whale (Megaptera novaeangliae). Contents of its gastrointestinal tract were sieved, dissolved in 10% potassium hydroxide and washed. From the remaining dried material, potential synthetic polymer particles were selected based on density and appearance, and analysed by Fourier transform infrared (FTIR) spectroscopy. Several polymer types (polyethylene, polypropylene, polyvinylchloride, polyethylene terephthalate, nylon) were found, in varying particle shapes: sheets, fragments and threads with a size of 1mm to 17cm. This diversity in polymer types and particle shapes, can be interpreted as a representation of the varying characteristics of marine plastic and the unselective way of ingestion by M. novaeangliae.


Assuntos
Monitoramento Ambiental , Conteúdo Gastrointestinal , Jubarte , Plásticos/análise , Poluentes da Água/análise , Animais , Cetáceos
12.
Leukemia ; 29(3): 696-704, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25102945

RESUMO

Multiple myeloma is a mostly incurable malignancy characterized by the expansion of a malignant plasma cell (PC) clone in the human bone marrow (BM). Myeloma cells closely interact with the BM stroma, which secretes soluble factors that foster myeloma progression and therapy resistance. Growth arrest-specific gene 6 (Gas6) is produced by BM-derived stroma cells and can promote malignancy. However, the role of Gas6 and its receptors Axl, Tyro3 and Mer (TAM receptors) in myeloma is unknown. We therefore investigated their expression in myeloma cell lines and in the BM of myeloma patients and healthy donors. Gas6 showed increased expression in sorted BMPCs of myeloma patients compared with healthy controls. The fraction of Mer(+) BMPCs was increased in myeloma patients in comparison with healthy controls whereas Axl and Tyro3 were not expressed by BMPCs in the majority of patients. Downregulation of Gas6 and Mer inhibited the proliferation of different myeloma cell lines, whereas knocking down Axl or Tyro3 had no effect. Inhibition of the Gas6 receptor Mer or therapeutic targeting of Gas6 by warfarin reduced myeloma burden and improved survival in a systemic model of myeloma. Thus, the Gas6-Mer axis represents a novel candidate for therapeutic intervention in this incurable malignancy.


Assuntos
Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Mieloma Múltiplo/genética , Plasmócitos/metabolismo , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/genética , Animais , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Mieloma Múltiplo/terapia , Transplante de Neoplasias , Plasmócitos/patologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais , Células Estromais/metabolismo , Células Estromais/patologia , Análise de Sobrevida , Varfarina/farmacologia , c-Mer Tirosina Quinase , Receptor Tirosina Quinase Axl
13.
Toxicol Lett ; 40(1): 1-9, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3341047

RESUMO

Interactions of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and estradiol were studied in three strains of mice: CD-1 and C57B/6 (TCDD sensitive) and DBA/2 (TCDD resistant at lower doses). Immature females were injected with 0-200 ng/kg/day estradiol for 2 weeks, s.c. On days 7, 9, 11, and 13, mice received 10 micrograms TCDD/kg by gavage. Relative uterine weight increased in mice of all three strains treated with estradiol alone. Uterine imbibition was suppressed by TCDD treatment, although this effect was antagonized in a saturable manner by coadministration of estradiol. TCDD induced aryl hydrocarbon hydroxylase (AHH) in liver microsomes of treated mice independent of estradiol dose and strain of mice (the dose of TCDD used was high enough to cause AHH induction in the resistant DBA/2 mice). Treatment of CD-1 mice, but not other strains, with TCDD and estradiol resulted in a decrease in the electrophoretic band of hepatic microsomal proteins comigrating with cytochrome P-450a and epoxide hydrase.


Assuntos
Dioxinas/toxicidade , Estradiol/farmacologia , Camundongos Endogâmicos/fisiologia , Microssomos Hepáticos/enzimologia , Dibenzodioxinas Policloradas/toxicidade , Útero/efeitos dos fármacos , Fatores Etários , Animais , Hidrocarboneto de Aril Hidroxilases/metabolismo , Peso Corporal/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/metabolismo , Interações Medicamentosas , Feminino , Camundongos , Tamanho do Órgão/efeitos dos fármacos , Útero/anatomia & histologia
14.
Toxicol Lett ; 32(1-2): 123-32, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3738924

RESUMO

Weanling C57B/6 female mice treated with 6 micrograms/kg 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) 3 times a week for one month (total dose 72 micrograms/kg) were observed to have greatly reduced relative uterine weights and histopathological changes in the uterus. Weanling CD-1 female mice were then treated with estradiol (E2) subcutaneously daily for 2 weeks. Half the mice also received 10 micrograms/kg TCDD in corn oil: acetone (9:1) by gavage 4 times during the second week. Control mice received either no E2 or no TCDD. Mice were killed on day 15 and autopsied. Relative uterine weights increased with increasing E2 doses; however, TCDD decreased this effect of E2 markedly. Liver microsomes from these animals showed that cytochrome P1-450 and P3-450 and, aryl hydrocarbon hydroxylase (AHH) induction by TCDD were independent of E2 dosage. Epoxide hydrolase was induced in TCDD treated animals. Gels showed an E2 dose dependent decrease in a protein migrating near epoxide hydrolase and 'P-450a' in animals receiving both E2 and TCDD. These results suggest that: E2 may act at the TCDD receptor; the TCDD receptor may be related to the estrogen receptor; the anti-estrogenic effects of TCDD are possibly independent of the Ah locus and AHH induction, and in TCDD-treated mice a protein migrating near epoxide hydrolase and 'P-450a' may be controlled by estrogen levels.


Assuntos
Sistema Enzimático do Citocromo P-450/biossíntese , Dioxinas/toxicidade , Estradiol/farmacologia , Fígado/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , Útero/efeitos dos fármacos , Animais , Hidrocarboneto de Aril Hidroxilases/biossíntese , Relação Dose-Resposta a Droga , Epóxido Hidrolases/biossíntese , Estro/efeitos dos fármacos , Feminino , Fígado/enzimologia , Camundongos , Camundongos Endogâmicos , Tamanho do Órgão/efeitos dos fármacos
15.
J Am Psychoanal Assoc ; 48(4): 1097-127; discussion 1175-87, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11212184

RESUMO

This presentation focuses on the disorganized/disoriented (Group D) categories of infant, child, and adult attachment. The infant D category is assigned on the basis of interruptions and anomalies in organization and orientation observed during Ainsworth's strange situation procedure. In neurologically normal low-risk samples, D attachment is not substantially related to descriptions of infant temperament, and usually appears with respect to only one parent. At six, former D infants are often found to be role-inverting (D-Controlling) towards the parent, while drawings and separation-related narratives (D-Fearful) suggest continuing states of fear and disorganization. In adults, marked lapses in reasoning and discourse surrounding the discussion of loss or abuse during the Adult Attachment Interview (AAI) causes a transcript to be assigned to Unresolved/disorganized (U/d) adult attachment status, which predicts infant D attachment. Bowlby's theory is extended, with the proposal that certain forms of frightening parental behavior will arouse contradictory biologically channeled propensities to approach and to take flight from the parent. Maltreated infants are therefore highly likely to be disorganized. Also identified are subtler forms of frightening parental behavior (including dissociative behavior and anomalous forms of frightened behavior) that appear to lead to infant disorganization. This suggests that infant D attachment may at times represent a second-generation effect of the parent's own continuing unresolved responses to trauma. Infant D attachment predicts disruptive/aggressive and dissociative disorders in childhood and adolescence, while U/d adult attachment appears frequently in psychiatric and criminal populations. Clinical implications are discussed.


Assuntos
Atenção , Maus-Tratos Infantis/psicologia , Transtornos Dissociativos/psicologia , Transtorno Reativo de Vinculação na Infância/psicologia , Adolescente , Comportamento do Adolescente , Adulto , Criança , Comportamento Infantil , Pré-Escolar , Crime/psicologia , Medo , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Relações Pais-Filho , Transtorno Reativo de Vinculação na Infância/etiologia
18.
Unfallchirurg ; 111(7): 553-8, 2008 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-18210039

RESUMO

Melorheostosis is a rare, benign, and sporadically occurring osteosclerosis of unknown cause. The onset of the disease is usually in early adulthood. Melorheostosis affects both genders, develops progressively, and is usually limited to one side of the human body. The sclerosis originates predominantly from the cortices of the long bones of the lower limbs and rarely the upper limbs. Frequently, the sclerosis involves the soft tissue surrounding the affected bones which may cause limitations in the range of motion, contractures, deformities, and pain. Melorheostosis is usually diagnosed by radiograms. Pain relief and restoration of the full range of motion are the primary goals of the therapeutic approach. A good outcome cannot always be achieved and a recurrence of the disease happens very often.


Assuntos
Artralgia/etiologia , Artralgia/prevenção & controle , Instabilidade Articular/etiologia , Instabilidade Articular/cirurgia , Melorreostose/diagnóstico por imagem , Melorreostose/cirurgia , Adulto , Feminino , Humanos , Melorreostose/complicações , Pessoa de Meia-Idade , Radiografia , Resultado do Tratamento
19.
Z Orthop Unfall ; 146(5): 636-43, 2008.
Artigo em Alemão | MEDLINE | ID: mdl-18846492

RESUMO

AIM: The aim of the study was to investigate the effects of dexamethasone and cyclic mechanical strain on human bone marrow stromal cells (hBMSCs) in osteogenic differentiation by determing levels of mRNA of collagen I, II, III, tenascin C and Cbfa1. METHOD: hBMSCs from seven donors (32.5 +/- 6.2 years old) were cultivated with (D +) or without (D -) dexamethasone. After the second passage 2.2 x 10 (5) cells were seeded on flexible silicon dishes. A cyclic mechanical strain with an elongation of 2 % (D + 2; D - 2) or 8 % (D + 8; D - 8) was applied for three days with a stimulation time of three times for two hours each day. Cells were harvested on day 1, day 1 after stress (day 4) and day 4 after stress (day 7). mRNA expression of collagen I, II, III, tenascin C and Cbfa1 was investigated by RT-PCR. RESULTS: Cbfa1 mRNA levels were significantly different on different days (p < 0.05), and for strain on day 1: 8 %: 0.0291 +/- 0.0338 versus 0 %: 0.00 528 +/- 0.0127, p = 0.017; day 8: 8 %: 0.0411 +/- 0.116, 0 %: 0.00 103 +/- 0.00 217, p = 0.009. All other observed paramaters showed tendencies without significant differences. CONCLUSION: In the short-term over seven days, cyclic stretching is a stronger differentiation factor than dexamethasone.


Assuntos
Dexametasona/administração & dosagem , Mecanotransdução Celular/fisiologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Osteoblastos/citologia , Osteoblastos/fisiologia , Osteogênese/fisiologia , Adulto , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Elasticidade , Feminino , Glucocorticoides/administração & dosagem , Humanos , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Estresse Mecânico
20.
Z Orthop Unfall ; 146(6): 747-53, 2008.
Artigo em Alemão | MEDLINE | ID: mdl-19085724

RESUMO

AIM: Novice drivers are at high risk for crash involvement. We performed an analysis of causations, injury patterns and distributions of novice drivers in cars and on motorcycles in road traffic as a basis for proper measurements. METHOD: Data of accident and hospital records of novice drivers (licence < 2 years) were analysed focusing on the following parameters: injury type, localisation and mechanism, abbreviated injury scale (AIS), maximum AIS (MAIS), delta-v, collision speed and other technical parameters and compared with those of experienced drivers. RESULTS: In 18 352 accidents in the area of Hannover (years 1985-2004), 2602 novice drivers and 18 214 experienced drivers were recorded as having an accident. Novice car drivers were more often and more severely injured whereas on motorcycles the experienced drivers were at higher risk. Novice drivers of both groups sustained more often extremity injuries. 4.5 % of the novice car drivers were not restrained by seatbelts as compared to 3.7 % of the experienced drivers and 6.1 % of the novice motorcycle drivers did not wear a proper helmet (versus 6.5 %). Severe injuries were sustained in 20 % at collision speeds below 30 km/h and in 80 % at collision speeds above 50 km/h. Novice car drivers drove significantly older cars. The risk profile of novice drivers is similar to that of drivers older than 65. CONCLUSION: Structural protection and special lectures like skidding courses could be proper measurements next to harder punishment of violations.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Condução de Veículo/educação , Automóveis/estatística & dados numéricos , Motocicletas/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Escala Resumida de Ferimentos , Adolescente , Adulto , Fatores Etários , Condução de Veículo/estatística & dados numéricos , Causalidade , Estudos Transversais , Feminino , Alemanha , Dispositivos de Proteção da Cabeça/estatística & dados numéricos , Humanos , Incidência , Masculino , Estudos Prospectivos , Cintos de Segurança/estatística & dados numéricos , Fatores Sexuais , Revisão da Utilização de Recursos de Saúde/estatística & dados numéricos , Adulto Jovem
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