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11.
Per H. Morberg Olle G. P. Isaksson Carina B. Johansson Jonas Sandstedt Jan F. T rnell 《Acta orthopaedica》1997,68(4):344-348
Several recent studies have investigated the effects of growth hormone (GH) on the healing of fractures and bone ingrowth, but with conflicting results. The negative results may be due to antibody formation against injected GH or because some experimental models are able to prove only positive GH effects. In this study, we wanted to investigate the effect of GH on implant integration in bone. To avoid potential formation of antibodies against injected GH, we used a model with transgenic mice overexpressing bovine GH (bGH).
Titanium implants were inserted in the forehead of the mice. 4 months after insertion, the implants were cut out en bloc with the surrounding bone. The calcified specimens were cut and ground to a thickness of approximately 10m. Histomorphometry demonstrated significantly more direct bone-to-metal contact in the transgenic mice than in the nontransgenic littermates. Our findings indicate that systemic administration of GH in humans may improve implant integration in bone. 相似文献
Titanium implants were inserted in the forehead of the mice. 4 months after insertion, the implants were cut out en bloc with the surrounding bone. The calcified specimens were cut and ground to a thickness of approximately 10m. Histomorphometry demonstrated significantly more direct bone-to-metal contact in the transgenic mice than in the nontransgenic littermates. Our findings indicate that systemic administration of GH in humans may improve implant integration in bone. 相似文献
12.
Francisco Airton Castro da Rocha Artur José de Brum-Fernandes 《Journal of bone and mineral research》2002,17(3):434-442
Peroxynitrite (PN), a nitric oxide (NO*)-derived anion, has been associated with NO* damage in various cell types. We examined the effects of adding PN to cultured human osteoblast-like (hOB) cells obtained after hip arthroplasty. Exposure to PN (0.1-0.4 mM) decreased both hOB proliferation and differentiation, measured by [3H]thymidine uptake and alkaline phosphatase production, respectively. Incubation with 3-morpholinosydnonimine (SIN-1; 0.25-1 mM), an NO* and O2- donor that leads to PN release, also reduced both hOB proliferation and differentiation. Coincubation with both superoxide dismutase (SOD; 100 U/ml) and catalase (CAT; 50 U/ml), rendering SIN-1 a pure NO* donor, reversed its effects on hOB proliferation and differentiation. However, SIN-1-induced NO* production, measured by nitrite release to the hOB medium, was not altered by cotreatment with SOD and CAT. Expression of nitrotyrosine by hOB, a marker of PN action, was significantly increased after SIN-1 addition, as compared with untreated cells, as revealed by Western blot analysis. Interleukin-1alpha (IL-1alpha) and interferon gamma (IFN-gamma) but not tumor necrosis factor alpha (TNF-alpha) also significantly increased nitrotyrosine expression in these cells. These data show that PN is at least partially responsible for osteoblast derangement by NO* and that cytokines released during inflammatory arthropathies can induce PN production in hOB cells. 相似文献
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The effects of chronic dietary protein restriction on ischemic renal failure were evaluated in rats subjected to 90 min of bilateral renal clamping. The rats were kept on either 20% casein (regular) diet or casein-free (protein-free) diet 10 days before and 21 days after renal injury. Rats on regular protein diet showed higher levels of BUN and serum creatinine and had a lower inulin clearance (microliter/min/100 g BW) than animals on protein-free diet (289 +/- 34 vs 582 +/- 103, p less than 0.05) 2 days after ischemia. However, the inulin clearance measured 21 days following ischemia was significantly higher in rats on regular diet (1468 +/- 181) than those maintained on protein-free diet after ischemia (560 +/- 167). When unilateral 90 min ischemia was performed in rats on regular diet, the postischemic kidneys showed an incomplete recovery of the inulin clearance (226 +/- 35) compared to the contralateral kidney (900 +/- 116), 21 days after ischemia; whereas in rats on a protein-free diet the inulin clearance averaged 106 +/- 17 in the postischemic kidney and 345 +/- 41 in the right kidney. When left renal ischemia and contralateral nephrectomy were performed, the inulin clearance was 1149 +/- 74 in rats on regular diet and 534 +/- 60 in rats on protein-free diet, 21 days following renal insult. These results suggest that protein restriction can play a protective role against renal ischemia in an initial phase, but it limits the late recovery from ischemia. The presence of a normal contralateral kidney inhibits the functional recovery of the postischemic kidney and a contralateral nephrectomy produces a compensatory functional hypertrophy of the postischemic kidney, even in rats on a protein-free diet. 相似文献
15.
BACKGROUND/AIMS: Hepatocytes (HEP) have been the major target for structural quantification in the liver, but an estimation of their total number (N), their percentage in relation to the global number of liver cells and the evaluation of the percentage of binucleated hepatocytes (BnHEPs) have never been performed with modern design-based stereological techniques. The establishment of sound technical guidelines and baseline quantitative data in non-pathological conditions are relevant to properly evaluate HEP hyperplasia and BnHEP responses. METHODS: In this study, we combined immunocytochemistry with sound design-based stereology for estimating the N of HEP and the N of non-hepatocytic cells (NHCs). For obtaining systematic uniform random sections (30 microm thick), a smooth fractionator sampling scheme was applied to the liver of five male Wistar rats (3 month old). Those sections were immunostained with polyclonal antibodies against carcinoembryonic antigen. Because biliary canaliculi were then marked, an unequivocal counting of mononucleated hepatocytes (MnHEP) and BnHEP was allowed. RESULTS: The N of HEP was estimated to be 1.93 x 10(9), with a coefficient of error (CE) of 0.02, corresponding to 129 x 10(6) HEP/g of liver. BnHEP represented 26% of total HEP number. The N of NHC was estimated as 1.31 x 10(9) (CE=0.02). CONCLUSION: The strategy here presented provides a reliable method for accessing the N of HEP (distinguishing MnHEP from BnHEP) in situations in which these parameters are relevant, namely for evaluating the magnitude of an hyperplastic liver response from its very early onset. 相似文献
16.
M G Brand?o T S Grandi E M Rocha D R Sawyer A U Krettli 《Journal of ethnopharmacology》1992,36(2):175-182
Plants traditionally employed for the treatment of malaria in certain areas of Brazil, where this disease is prevalent, were surveyed by interviewing natives and migrants in the Amazon Region. Forty-one plants used for malarial treatment and/or for the related symptoms (fever and liver disorders) were collected and identified. Given the potential of Brazil's forests and medicinal plants, research on traditional plant-based remedies in this country may lead to the development of new drugs. 相似文献
17.
Lars Hellgren Christopher Gillberg I. Carina Gillberg 《European child & adolescent psychiatry》1994,3(1):1-15
Fifty-six children with and forty-five children without deficits in attention, motor control and perception (DAMP) had been recruited from the general population at age 7 years. They were followed up neuropsychiatrically at age 16 years after intermediate term follow up at age 10 and 13 years. Cases were subdivided into those with good and not good outcome on the basis of absence or presence of psychiatric and personality disorders, multiple traumatic accidents and speech and language problems at age 16 years. The presence of DAMP in itself was the strongest predictor of poor outcome. High scores for minor neurological dysfunction, low performance IQ, autistic features at age 7 years and poor reading skills at age 10 and/or 13 years were important background factors in cases with poor outcome. In the small subgroup with poor outcome among those without DAMP at age 7 years, major life events was the most important background factor.
Zusammenfassung 56 Kinder mit und 45 Kinder ohne Störungen der Aufmerksamkeit, der motorischen Kontrolle und der Wahrnehmung (DAMP) waren aus einer Gesamtpopulation 7jÄhriger rekrutiert worden. Sie wurden neuropsychiatrisch im Alter von 16 jahren nachuntersucht, nachdem zwischenzeitliche Untersuchungen im Alter von 10 und 13 Jahren erfolgt waren. Die Probanden wurden in solche mit gutem und nicht gutem Ausgang unterteilt, in AbhÄngigkeit vom Vorliegen psychiatrischer AuffÄlligkeiten, Persönlichkeitsstörungen, multiplen Traumata und Sprech- und Sprachproblemen im Alter von 16 Jahren. Das Vorhandensein von DAMP war der stÄrkste PrÄdiktor für einen schlechten Ausgang. Hohe Werte für leichte neurologische AuffÄlligkeiten, ein niedriger Handlungs-IQ, autistische Züge im Alter von 7 Jahren und schlechte LesefÄhigkeiten im Alter von 10 und/oder 13 Jahren waren wichtige Hintergrundfaktoren bei den Probanden mit einem schlechten Ausgang. In der kleinen Untergruppe mit einem schlechten Ausgang bei den Kindern, die im Alter von 7 Jahren kein DAMP ausgewiesen hatten, bildeten schwerwiegende Lebensereignisse den wichtigsten Hintergrundfaktor.
Résumé Cinquante-six enfants atteints et quarante-cinq enfants non atteints de déficits de l'attention, du contrÔle moteur et de la perception (DAMP), ont été recrutés en population générale à l'âge de 7 ans. Ils ont été évalués sur la plan neuropsychiatrique à l'âge de 16 ans, après des évaluations intermédiaires à l'âge de 10 et 13 ans. Les cas ont été subdivisés entre bons et mauvais devenir sur la base de la présence ou de l'absence de troubles de la personnalité, l'importance du nombre d'accidents traumatiques, les difficultés d'élocution et de langage à 16 ans. La présence de DAMP était en soi, le facteur prédictif le plus important de mauvais devenir. Des scores élevés à des dysfonctionnements neurologiques mineurs, un QI bas, des traits autistiques à l'âge de 7 ans, et de mauvaises capacités en lecture à l'âge de 10 ou 13 ans ont été des facteurs importants dans les cas de mauvais devenir. Dans le petit sous-groupe à mauvais devenir caractérisé par une absence de DAMP à l'âge de 7 ans, des événements de vie marquants ont semblé Être des antécédents importants.相似文献
18.
C-fos immunoreactivity was used to reveal brain areas in which neurons were influenced by electrical stimulations applied to the dorsal periaqueductal gray. These stimulations were applied in freely moving rats so that the resulting behaviors could be observed. Shortly afterwards, the brains of the rats were processed for C-fos immunoreactivity. In order to determine the specificity of the brain areas thus labeled, control stimulations were applied to the ventral tegmental area of other rats. Immunoreactive cells were found surrounding the tip of the stimulation electrode within a radius of 0.5 mm. This labeled area extended further along the rostro-caudal axis than along the medio-lateral or dorso-ventral axis in the periaqueductal gray. Distally, clusters of labeled cells were found ipsilaterally in the caudal periaqueductal gray extending to the nucleus cuneiformis, and bilaterally in the locus coeruleus and supramamillary decussation. More widespread labeling was found in most hypothalamic subareas and in the lateral habenula. The labeled brain areas following ventral tegmental area stimulations were totally distinct, and comprised the medial forebrain bundle, the nucleus accumbens, the vertical limb of the diagonal band and the medial septum. The pattern of labeling produced by periaqueductal gray stimulations was therefore specific, and provided information about brain structures involved in the motivational and behavioral effects of such stimulations. 相似文献
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20.
Marie Louise Hall-Lord PhD RNT Bodil Wilde Larsson PhD RNT Carina Bth MsC RN Inger Johansson PhD RNT 《Journal of Orthopaedic Nursing》2004,8(4):76
The aims were to investigate: (1) experiences of physical pain in elderly patients with hip fracture; (2) if background variables, confusion, experiences of pain and distress and interventions aimed at reducing pain and distress, functional ability, pain in the ambulance, and type of fracture varied between patients with more intense physical pain and patients with less intense physical pain. The sample included 49 patients, 70 years or older, with hip fracture. Structured instruments were used to interview and observe the patients on four occasions during the hospital stay. The patients’ experiences of physical pain decreased during the hospital stay. Physical pain at rest was lower than pain with movement. Patients who scored physical pain as more intense (group B) during the visit to the hospital had significantly more unfavourable experiences in the sensory, emotional, and existential dimensions the day before discharge from the hospital compared with the patients who scored pain as less intense (group A). The patients in group B perceived the interventions as less favourable than group A. Furthermore, group B had more intense physical pain in the ambulance than the patients in the other group. More patients in group B than in group A had additional health problems. 相似文献