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61.

INTRODUCTION

We describe our experience with oncology patients on a frequent dosing schedule of intravenous (i.v.) bisphosphonates at the Jordan University Hospital (JUH).

PATIENTS AND METHODS

Patients treated by i.v. bisphosphonates in the medical oncology unit at the JUH were examined for bisphosphonate-related osteonecrosis of the jaws (BRONJ). Diagnosis was made according to the guidelines of the American Association of Oral and Maxillofacial Surgeons (AAOMS) original position paper.

RESULTS

Of the 41 patients, four developed BRONJ, two in maxilla, one in mandible and one bimaxillary. Patients with BRONJ were older; mean age was 69.3 ±3.1 years compared to 62.8 ± 12.5 years (P = 0.022). Dental co-morbidities were more commonly present in patients with the disease (P = 0.038). Patients who developed BRONJ were on treatment for a longer duration of time; the mean duration of treatment was 23.5 ± 8.4 months compared to 11.9 ± 13.4 months (P = 0.10).

CONCLUSIONS

The results of this case series demonstrated that age and poor oral health status are significant risk factors of BRONJ for oncology patients on long-term frequent dosing schedule of i.v. bisphosphonates.  相似文献   
62.
Transition to diets that are high in saturated fat and sugar has caused a global public health concern, as the pattern of food consumption is a major modifiable risk factor for chronic non-communicable diseases. Although agri-food systems are intimately associated with this transition, agriculture and health sectors are largely disconnected in their priorities, policy, and analysis, with neither side considering the complex inter-relation between agri-trade, patterns of food consumption, health, and development. We show the importance of connection of these perspectives through estimation of the eff ect of adopting a healthy diet on population health, agricultural production, trade, the economy, and livelihoods,with a computable general equilibrium approach. On the basis of case-studies from the UK and Brazil, we suggest that benefits of a healthy diet policy will vary substantially between different populations, not only because of population dietary intake but also because of agricultural production, trade, and other economic factors.  相似文献   
63.

Introduction

Silver dressings are an integral part of the management of burn patients. Package inserts assert a lack of compatibility and safety with magnetic resonance imaging (MRI) and recommend removal prior to any MRI procedure, although there is no clear evidence to support this recommendation. Dressing removal is associated with increased pain, anxiety, stress, and analgesia use. This study was to determine whether these products produce MRI image distortion or if the agitation of the silver particles generates enough heat which might produce further skin damage.

Methods

Hind limbs from euthanized pigs were used in a 7 T MRI scanner with three standard silver wound dressings. Images were obtained with both dry and wet dressings. Temperature was assessed before and during MRI by probes inserted between the dressing and skin. Images were independently reviewed by a radiologist and MR physicist for distortion.

Results

None of the dressings exhibited significant temperature increases nor produced significant distortion that influenced imaging quality.

Conclusion

Our data suggests silver containing wound dressings do not cause a significant increase in dressing temperature or image distortion and thus their removal is not warranted for clinical MRI examinations.  相似文献   
64.
The relative contributions of the direct and indirect pathways in alloimmune responses have not been fully elucidated. We report a novel murine TCR transgenic system that can simultaneously track the CD4-direct (CD4-d), CD4-indirect (CD4-i) and CD8-direct (CD8-d) pathways after transplantation. Using this system, we have observed a profoundly greater proliferation of CD4-i T cells relative to CD4-d and CD8-d T cells after transplantation. Furthermore, a much larger proportion of CD4-i T cells attain an effector phenotype. We also analyzed endogenous, wild-type T cells using enzyme-linked immunospot analysis. In naïve mice, T cells with indirect reactivity were undetectable, but T cells with direct reactivity were abundant. However, 10 days after skin or heterotopic heart transplantation, CD4-i T cells comprised approximately 10% of the CD4+ response. Consistent with increased priming of the CD4-i pathway, we observed that the CD4-i T cells were further enriched in the effector cells migrating to the allograft and in memory-like T cells persisting after rejection. Thus, priming of the CD4-i pathway is favored after transplantation, allowing a rare population to rapidly become a major component of the CD4+ T-cell response in acute allograft rejection. The generalizability of this observation to other models remains to be determined.  相似文献   
65.
Periodontal disease involves complex interactions of microorganisms and host defenses. This work investigated the associations between putative bacterial pathogens, herpesviruses and chronic periodontitis. Subgingival samples were collected from 40 periodontally healthy individuals and from 40 patients with chronic periodontitis with probing depths of ≤3 mm or ≥6 mm. Multiplex and nested polymerase chain reactions were used to identify bacterial pathogens and herpesviruses. Porphyromonas gingivalis, Tannerella forsythia, Epstein–Barr virus (EBV) type 1, cytomegalovirus (CMV), Aggregatibacter actinomycetemcomitans and EBV type 2 were detected in, respectively, 95, 75, 72.5, 50, 12.5 and 10% of sites with probing depths ≥6 mm. P. gingivalis, T. forsythia, EBV‐1 and CMV were statistically associated with probing depths ≥6 mm. A. actinomycetemcomitans and EBV‐2 showed no association with periodontitis sites, and no significant associations were found for any of the test infectious agents and probing depths ≤3 mm. Our results confirm an association between P. gingivalis, T. forsythia, EBV‐1 and CMV, and chronic periodontitis. These infectious agents may play an important synergistic role in the pathogenesis of chronic periodontitis.  相似文献   
66.
The renin-angiotensin-aldosterone system (RAAS) plays a dominant role in the pathophysiology of hypertension, Diabetes mellitus (DM), chronic kidney disease (CKD) and chronic heart failure (CHF). Therefore, drugs that block key components of the RAAS such as ACE inhibitors (ACEi) and angiotensin receptor blockers (ARBs) have gained wide clinical use for these indications. Despite progress, the morbidity and mortality of patients treated with ACEi or ARBs remain high. Small molecules that directly inhibit renin (DRI) and are orally active have also been developed and one such drug, aliskiren, was introduced into clinical use for treatment of hypertension in 2007. Further clinical trials aimed to expand the therapeutic use of aliskiren are in progress for CKD-DM and CHF. In this review we analyze and review the translational medicine prospects of aliskiren in respect to the biochemical pharmacology of the RAAS, the marketed RAAS modulators and the new emerging science regarding the role of prorenin, renin and renin receptors in cardiovascular biology and disease. The information already gained with aliskiren, raises questions regarding the advantages of DRIs as monotherapy compared to marketed ACEis and ARBs, their potential added value in combination with other RAAS modulators and other unproven benefits in relation to prorenin and renin receptor biology. This review will also indicate basic and clinical research needs that are critical to determine whether DRIs can provide meaningful added medical benefits over contemporary medicines that regulate the RAAS, and the need to identify patients that are more likely to benefit from DRIs and any possible long term adverse effects.  相似文献   
67.

Background

We describe a project to quantify the burden of heat and ozone on mortality in the UK, both for the present-day and under future emission scenarios.

Methods

Mortality burdens attributable to heat and ozone exposure are estimated by combination of climate-chemistry modelling and epidemiological risk assessment. Weather forecasting models (WRF) are used to simulate the driving meteorology for the EMEP4UK chemistry transport model at 5 km by 5 km horizontal resolution across the UK; the coupled WRF-EMEP4UK model is used to simulate daily surface temperature and ozone concentrations for the years 2003, 2005 and 2006, and for future emission scenarios. The outputs of these models are combined with evidence on the ozone-mortality and heat-mortality relationships derived from epidemiological analyses (time series regressions) of daily mortality in 15 UK conurbations, 1993-2003, to quantify present-day health burdens.

Results

During the August 2003 heatwave period, elevated ozone concentrations > 200 μg m-3 were measured at sites in London and elsewhere. This and other ozone photochemical episodes cause breaches of the UK air quality objective for ozone. Simulations performed with WRF-EMEP4UK reproduce the August 2003 heatwave temperatures and ozone concentrations. There remains day-to-day variability in the high ozone concentrations during the heatwave period, which on some days may be explained by ozone import from the European continent.Preliminary calculations using extended time series of spatially-resolved WRF-EMEP4UK model output suggest that in the summers (May to September) of 2003, 2005 & 2006 over 6000 deaths were attributable to ozone and around 5000 to heat in England and Wales. The regional variation in these deaths appears greater for heat-related than for ozone-related burdens.Changes in UK health burdens due to a range of future emission scenarios will be quantified. These future emissions scenarios span a range of possible futures from assuming current air quality legislation is fully implemented, to a more optimistic case with maximum feasible reductions, through to a more pessimistic case with continued strong economic growth and minimal implementation of air quality legislation.

Conclusion

Elevated surface ozone concentrations during the 2003 heatwave period led to exceedences of the current UK air quality objective standards. A coupled climate-chemistry model is able to reproduce these temperature and ozone extremes. By combining model simulations of surface temperature and ozone with ozone-heat-mortality relationships derived from an epidemiological regression model, we estimate present-day and future health burdens across the UK. Future air quality legislation may need to consider the risk of increases in future heatwaves.
  相似文献   
68.
Deformation analysis using 2-dimensional strain echocardiography can detect early systolic function abnormalities in patients with left ventricular hypertrophy. This study was designed to characterize global and regional myocardial deformation using 2-dimensional strain in professional soccer players (PSPs) compared with control subjects and patients with hypertrophic cardiomyopathy (HC). Twenty nine PSPs, 26 patients with HC, and 17 controls were investigated at rest using transthoracic echocardiography with 2-dimensional strain analysis. Radial and transverse strains were significantly higher in PSPs compared with controls, whereas longitudinal strain was lower. Compared with patients with HC, athletes had higher values for transverse, radial, and circumferential strains. In pathologic hypertrophic segments, longitudinal strain was lower in patients with HC than in PSPs. In conclusion, 2-dimensional strain can identify specific patterns of myocardial deformation in PSPs, controls, and patients with HC. It has the potential to become a routinely used method for the differentiation of athlete's heart and HC.  相似文献   
69.
Cotard's syndrome is a rare syndrome, characterized by the presence of nihilistic delusions. The syndrome is typically related to depression and is mostly found in middle-aged or older people. A few cases have been reported in young people with 90% of these being females. We present a case of a young pregnant woman suffering from Cotard's syndrome. This is the first report of this syndrome in a pregnant woman. The case was diagnosed late, due to lack of awareness of psychiatric problems in primary care physicians resulting in undue suffering, loss of precious time and resources for the patient. Besides highlighting the rare combination of pregnancy and Cotard's syndrome this report delineates the difficulties faced by patients with such symptoms in a low resource setting.  相似文献   
70.
Drug interactions with herbal medicines   总被引:3,自引:0,他引:3  
The use of herbal medicines (HM) is on the rise among the global population. Although the safety profile of many herbal medicines is promising, accumulated data show evidence of significant interactions with medications, which can place individual patients at great risk. A range of electronic databases have been reviewed for articles published in this field: Medline, Allied and Complementary Medicine Database, HealthSTAR, AMBASE, CINHAL, Cochrane Library, as well as Internet documents and manually searched references in medical journals. In this review, we examined the literature from 1966 to 2006 and focused on the importance of the risk of drug interactions and potential side effects when HM are involved. We discuss these in light of the documented findings. A review of the problematic issues is given and recommendations are made in order to encourage the setting up of clinical trials on HM and herb-drug interactions.  相似文献   
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