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81.
Tu X Rhee Y Condon KW Bivi N Allen MR Dwyer D Stolina M Turner CH Robling AG Plotkin LI Bellido T 《BONE》2012,50(1):209-217
Sclerostin, the Wnt signaling antagonist encoded by the Sost gene, is secreted by osteocytes and inhibits bone formation by osteoblasts. Mechanical stimulation reduces sclerostin expression, suggesting that osteocytes might coordinate the osteogenic response to mechanical force by locally unleashing Wnt signaling. To investigate whether sclerostin downregulation is a pre-requisite for load-induced bone formation, we conducted experiments in transgenic mice (TG) engineered to maintain high levels of SOST expression during mechanical loading. This was accomplished by introducing a human SOST transgene driven by the 8 kb fragment of the DMP1 promoter that also provided osteocyte specificity of the transgene. Right ulnae were subjected to in vivo cyclic axial loading at equivalent strains for 1 min/day at 2 Hz; left ulnae served as internal controls. Endogenous murine Sost mRNA expression measured 24 h after 1 loading bout was decreased by about 50% in TG and wild type (WT) littermates. In contrast, human SOST, only expressed in TG mice, remained high after loading. Mice were loaded on 3 consecutive days and bone formation was quantified 16 days after initiation of loading. Periosteal bone formation in control ulnae was similar in WT and TG mice. Loading induced the expected strain-dependent increase in bone formation in WT mice, resulting from increases in both mineralizing surface (MS/BS) and mineral apposition rate (MAR). In contrast, load-induced bone formation was reduced by 70-85% in TG mice, due to lower MS/BS and complete inhibition of MAR. Moreover, Wnt target gene expression induced by loading in WT mice was absent in TG mice. Thus, downregulation of Sost/sclerostin in osteocytes is an obligatory step in the mechanotransduction cascade that activates Wnt signaling and directs osteogenesis to where bone is structurally needed. 相似文献
82.
Pterostilbene and cancer: current review 总被引:2,自引:0,他引:2
Pterostilbene (trans-3,5-dimethoxy-4-hydroxystilbene) is an antioxidant that is primarily found in blueberries. Studies suggest that pterostilbene exhibits the hallmark characteristics of an effective anticancer agent based on its antineoplastic properties in several common malignancies. In vitro models have shown that pterostilbene inhibits cancer growth through alteration of the cell cycle, induction of apoptosis, and inhibition of metastasis. In vivo, pterostilbene inhibits tumorigenesis and metastasis with negligible toxicity. Pterostilbene has also been shown to be effective as an inducer of antioxidant capacity in multiple cancer cell lines that may facilitate its function as an anticarcinogenic compound. Additionally, preliminary studies show that pterostilbene exhibits much greater bioavailability compared with other stilbene compounds; however the exact pharmacologic mechanism of pterostilbene and its effects in humans are still under investigation. In this review, we present a comprehensive summary of the antineoplastic mechanisms of pterostilbene based on the results of preclinical studies and highlight recent advances in the study of this dietary compound. 相似文献
83.
Aneurysms are rare in children. Causes include congenital, traumatic, inflammatory, and infectious etiologies. When and how to best surgically treat arterial aneurysms in a child remain unclear. We present the case of a 3-month-old child with an aneurysm of the left common iliac artery, which was first detected on abdominal ultrasound and was successfully repaired with a cadaveric vein graft. 相似文献
84.
Prenatal ultrasound and fetal MRI: the comparative value of each modality in prenatal diagnosis 总被引:1,自引:0,他引:1
Fetal MRI is used with increasing frequency as an adjunct to ultrasound (US) in prenatal diagnosis. In this review, we discuss the relative value of both prenatal US and MRI in evaluating fetal and extra-fetal structures for a variety of clinical indications. Advantages and disadvantages of each imaging modality are addressed. In summary, MRI has advantages in demonstrating pathology of the brain, lungs, complex syndromes, and conditions associated with reduction of amniotic fluid. At present, US is the imaging method of choice during the first trimester, and in the diagnosis of cardiovascular abnormalities, as well as for screening. In some conditions, such as late gestational age, increased maternal body mass index, skeletal dysplasia, and metabolic disease, neither imaging method may provide sufficient diagnostic information. 相似文献
85.
Shahinfar S Dickson TZ Ahmed T Zhang Z Ramjit D Smith RD Brenner BM;RENAAL Investigators 《Kidney international. Supplement》2002,(82):S64-S67
BACKGROUND: Recently, the Reduction of Endpoints in NIDDM with the Angiotensin II Antagonist Losartan (RENAAL) Study demonstrated the benefit of losartan in reducing renal outcomes in patients with type 2 diabetes and proteinuria. Additional questions concerning the reduction of proteinuria and its relationship to end-stage renal disease (ESRD) as well as cardio-renal outcomes and the safety and tolerability of losartan remain to be addressed. METHODS: Three analyses were performed: (a) the impact of losartan on the relationship between the reduction of proteinuria and ESRD; (b) a time-to-event analysis of the cardio-renal composite endpoint of ESRD, myocardial infarction, stroke or all-cause death; and (c) additional analyses of adverse events, particularly in patients with serum creatinine >or=2.0 mg/dL. RESULTS: After adjusting the values for proteinuria over the entire study, the reduction of proteinuria accounted for approximately half of the treatment effect of losartan on the risk reduction for ESRD. In addition, losartan was associated with a 21% risk reduction for the composite cardio-renal outcome (P=0.003). The addition of losartan to a conventional antihypertensive regimen did not increase the overall incidence of adverse events, regardless of severity of renal impairment. CONCLUSIONS: Losartan significantly reduced the risk of cardiorenal outcomes and was well tolerated by patients, including those with serum creatinine levels >or=2.0 g/dL. In addition, although this study shows that the reduction of proteinuria does not completely explain the impact of intervention on outcomes such as ESRD, reduction of proteinuria must remain an important consideration when treating patients with type 2 diabetes and nephropathy. However, the reduction of outcomes such as ESRD should remain the goal of therapy when evaluating renal protection in this patient population. 相似文献
86.
Deferrari G Ravera M Deferrari L Vettoretti S Ratto E Parodi D 《Journal of the American Society of Nephrology : JASN》2002,13(Z3):S224-S229
Aggressive treatment of hypertension is effective in reducing both microvascular and macrovascular complications in type 2 diabetes, and target BP less than 130/85 or 130/80 mmHg are now recommended. Inhibition of renin angiotensin aldosterone system (RAAS) plays an essential role in the treatment of hypertension and diabetes-related complications. Studies focusing on renal end-points suggest that angiotensin-converting enzyme inhibitors (ACE-I) are more effective than other traditional agents in reducing the onset of clinical proteinuria in both type 1 and type 2 diabetic patients with incipient nephropathy, mainly in normotensive ones (secondary prevention). However, several small trials in type 2 diabetic patients with overt nephropathy (tertiary prevention) failed to demonstrate a specific renoprotective role for ACE-I, at variance with type 1 diabetes. Three recent large trials address the question of whether angiotensin II receptor blockers (ARB) prevent the development of clinical proteinuria or delay the progression of nephropathy in type 2 diabetes. The IRMA study showed that irbesartan is more effective than conventional therapy in preventing the development of clinical proteinuria and in favoring the regression to normoalbuminuria for comparable BP control in patients with incipient nephropathy. The IDNT and RENAAL trials showed that ARB are more effective than traditional antihypertensive therapies in reducing progression toward end-stage renal failure (ESRF) in type 2 diabetic patients with overt nephropathy independently of changes in BP. Moreover, a reduction in hospitalizations for heart failure was demonstrated for ARB-treated patients compared with placebo. Furthermore, the LIFE study showed that losartan is more effective than conventional therapy in reducing cardiovascular morbidity and mortality in a cohort of diabetic patients with hypertension and left ventricular hypertrophy. In conclusion, ARB seem to be effective in both preventing renal damage and reducing progression toward ESRF in type 2 diabetic patients. Thus, the guidelines for the prevention and treatment of diabetic nephropathy are now changed. In type 1 diabetes ACE-I are the first-choice drug; in type 2 diabetes, ARB are considered first-choice drugs in secondary prevention as well as ACE-I and have been now elected the unique first-choice drug in tertiary prevention of ESRF. Finally, ARB should be considered as the first-choice drug in cardiovascular prevention too, as well as ACE-I. 相似文献
87.
Matthijs?P.?SomfordEmail author Rebecca?A.?Nieuwe Weme Inger?Sierevelt Denise?Eygendaal 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2017,27(7):883-887
Introduction
With a survey among Dutch orthopedic surgeons, we try to assess whether eponymous terms are still in use in daily practice. We also tried to find out whether younger generations tend to use them less than our older colleagues.Materials and methods
In a survey consisting of 57 eponymous terms, 67 participants were asked to mark the eponyms they knew and whether they used them in daily practice.Results
No correlation was observed in known/used eponyms or years of experience in 58 completed surveys. Respondents who classified themselves as trauma or general orthopedic surgeons knew or used a significantly higher number of eponyms in daily practice than orthopedic surgeons who classified themselves as spine, upper limb, lower limb, sports or pediatric surgeons.Discussion
Eponymous terms are used frequently in daily practice. Super-specialization might eradicate the general orthopedic surgeon, and the number of eponyms known and used might become smaller and more focused on the super-specialty.Conclusion
Our survey showed that eponymous terms are still used frequently in daily practice among both young and more senior orthopedic surgeons in The Netherlands.88.
89.
de Andrade AK Feist IS Pannuti CM Cai S Zezell DM De Micheli G 《Lasers in medical science》2008,23(4):341-347
The Nd:YAG laser efficacy associated with conventional treatment for bacterial reduction has been investigated throughout
literature. The purpose of this study was to evaluate the bacterial reduction after Nd:YAG laser irradiation associated with
scaling and root planning in class II furcation defects in patients with chronic periodontitis. Thirty-four furcation lesions
were selected from 17 subjects. The control group received conventional treatment, and the experimental group received the
same treatment followed by Nd:YAG laser irradiation (100 mJ/pulse; 15 Hz; 1.5 W, 60 s, 141.5 J/cm2). Both treatments resulted in improvements of most clinical parameters. A significant reduction of colony forming unit (CFU)
of total bacteria number was observed in both groups. The highest reduction was noted in the experimental group immediately
after the treatment. The number of dark pigmented bacteria and the percentage of patients with Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans reduced immediately after the treatment and returned to values close to the initial ones 6 weeks after the baseline for both
groups. The Nd:YAG laser associated with conventional treatment promoted significant bacterial reduction in class II furcation
immediately after irradiation, although this reduction was not observed 6 weeks after the baseline. 相似文献
90.
Stavros M Stivaros Robert Alston Neville B Wright Kate Chandler Denise Bonney Robert F Wynn Andrew M Will Maqsood Punekar Sean Loughran John-Paul Kilday Detlev Schindler Leena Patel Stefan Meyer 《The British journal of radiology》2015,88(1056)