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71.
Fracture risk in monoclonal gammopathy of undetermined significance.   总被引:3,自引:0,他引:3  
To assess fractures in monoclonal gammopathy of undetermined significance (MGUS), the precursor of multiple myeloma, we followed 488 Olmsted County, MN, residents with MGUS in a retrospective cohort study. There was a 2.7-fold increase in the risk of axial fractures but no increase in limb fractures. The pathophysiologic basis for the increased axial fractures should be determined. INTRODUCTION: Multiple myeloma is often preceded by monoclonal gammopathy of undetermined significance (MGUS). Fractures are common in myeloma as a result of lytic bone lesions, generalized bone loss, and elevated bone turnover from excessive cytokine production. Whether fractures are also increased in MGUS is unknown. MATERIALS AND METHODS: In a population-based retrospective cohort study, 488 Olmsted County, MN, residents with MGUS first diagnosed in 1960-1994 (52% men; mean age, 71.4 +/- 12.8 years) were followed for 3901 person-years; follow-up was censored at progression to myeloma. The relative risk of fractures was assessed by standardized incidence ratios (SIRs), and risk factors were evaluated in proportional hazards models. RESULTS AND CONCLUSIONS: Altogether, 200 patients experienced 385 fractures. Compared with expected rates in the community, statistically significant increases were seen for fractures at most axial sites, for example, vertebrae (SIR, 6.3; 95% CI, 5.2-7.5). There was a slight increase in hip (SIR, 1.6; 95% CI, 1.2-2.2) but not distal forearm fractures (SIR, 0.8; 95% CI, 0.4-1.5). The relative risk (SIR) of any axial fracture was 2.7 (95% CI, 2.3-3.1) compared with only 1.1 (95% CI, 0.9-1.4) for all limb fractures combined. In a multivariate analysis, the independent predictors of any subsequent fracture were age (hazard ratio [HR] per 10-year increase, 1.4; 95% CI, 1.2-1.6) and corticosteroid use (HR, 1.8; 95% CI, 1.2-2.6); greater weight at diagnosis (HR per 10 kg, 0.8; 95% CI, 0.8-0.9), and IgG monoclonal protein (HR, 0.7; 95% CI, 0.5-0.97) were protective. Baseline monoclonal protein level, a determinant of myeloma progression, did not predict fracture risk. Thus, the risk of axial, but not peripheral, fractures is increased among MGUS patients even before progression to myeloma. The pathophysiologic basis for this should be determined because elevated bone turnover, for example, might be treatable.  相似文献   
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73.
Polycyclic aromatic hydrocarbons (PAH), of which benzo[a]pyrene is a representative member, are combustion-related environmental pollutants and include known carcinogens. Laboratory animal studies indicate that the dose of PAHs to the fetus is on the order of a 10th that to the mother and that there is heightened susceptibility to PAH-induced carcinogenesis during the fetal and infancy periods. Carcinogen-DNA adducts, a measure of procarcinogenic genetic damage, are considered a biomarker of increased cancer risk. Here we compare the levels of benzo[a]pyrene-DNA adducts as a proxy for PAH-DNA damage measured in maternal blood and newborn cord blood obtained at delivery in four different populations of mothers (total of 867) and newborns (total of 822), representing a 30-fold range of exposure to ambient PAHs. The populations include residents in Northern Manhattan, participants in a study of the effects of the World Trade Center disaster, residents in Krakow, Poland, and residents in Tongliang, China. Mean adduct concentrations in both maternal and cord blood and the proportion of samples with detectable adducts, increased across the populations [Northern Manhattan < World Trade Center (WTC) < Krakow < Tongliang], consistent with the trend in estimated ambient exposure to PAHs (P < 0.001). For mothers, the means in the respective populations were Northern Manhattan (0.21 adducts per 10(8) nucleotides), WTC (0.23 adducts per 10(8) nucleotides), Krakow (0.28 adducts per 10(8) nucleotides), Tongliang (0.31 adducts per 10(8) nucleotides); the corresponding means in the newborns were Northern Manhattan (0.23), WTC (0.24), Krakow (0.29), Tongliang (0.31). The percentage of mothers with detectable levels of adducts in the respective populations were Northern Manhattan (36.8%), WTC (57.5%), Krakow (72.9%), Tongliang (73.4%); the corresponding percentages among the newborns were Northern Manhattan (42.4%), WTC (60.6%), Krakow (71.1%), Tongliang (79.5%). Despite the estimated 10-fold lower PAH dose to the fetus based on laboratory animal experiments, the adduct levels in the newborns were similar to or higher than in the mothers. This study suggests that the fetus may be 10-fold more susceptible to DNA damage than the mother and that in utero exposure to polycyclic aromatic hydrocarbons may disproportionately increase carcinogenic risk. The data support preventive policies to limit PAH exposure to pregnant women and children.  相似文献   
74.
75.
Background. Facial acne scarring has been treated with multiple methods with varying degrees of improvement. Although the 1,320 nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser has been widely used to improve photoaging, studies analyzing its effects on atrophic acne scarring are limited.
Objective. To evaluate the efficacy of a dynamic cryogen-cooled 1,320 nm Nd:YAG laser for the treatment of atrophic facial acne scars in a larger cohort of patients with long-term follow-up.
Methods. Twenty-nine patients (skin phototypes I–IV) with facial acne scarring received a mean of 5.5 (range 2–17) treatments with a 1,320 nm Nd:YAG laser. Objective physician assessment scores of improvement were determined by side-by-side comparison of preoperative and postoperative photographs at a range of 1 to 27 months (mean 10.4 months) postoperatively. Subjective patient self-assessment scores of improvement were also obtained.
Results. Acne scarring was significantly improved by both physician and patient assessment scores. Mean improvement was 2.8 (  p < .05  ) on a 0- to 4-point scale by physician assessment and 5.4 (  p < .05  ) on a 0- to 10-point scale by patient assessment. No significant complications were observed.
Conclusions. Nonablative laser skin resurfacing with a 1,320 nm Nd:YAG laser can effectively improve the appearance of facial acne scars with minimal adverse sequelae.  相似文献   
76.
We present a case of Bernard Soulier syndrome in a 9-year-old boy caused by a novel genetic mutation. This child was shown to be homozygous for a single nucleotide deletion (c.1077delG) in the GP1BA gene not previously reported. Clinically, the boy has become refractory to platelet transfusions with both allo-antibodies and iso-antibodies and a massive transfusion requirement for ongoing haemorrhage. We describe the critical role that the blood product transfusion continues to play in the management of Bernard Soulier syndrome and discuss therapeutic options in these patients.  相似文献   
77.
PURPOSE: This study aims to determine the effect of loss of breast cancer metastasis suppressor 1 (BRMS1) protein expression on disease-free survival in breast cancer patients stratified by estrogen receptor (ER), progesterone receptor (PR), or HER2 status, and to determine whether loss of BRMS1 protein expression correlated with genomic copy number changes. EXPERIMENTAL DESIGN: A tissue microarray immunohistochemical analysis was done on tumors of 238 newly diagnosed breast cancer patients who underwent surgery at the Cleveland Clinic between January 1, 1995 and December 31, 1996, and a comparison was made with 5-year clinical follow-up data. Genomic copy number changes were determined by array-based comparative genomic hybridization in 47 breast cancer cases from this population and compared with BRMS1 staining. RESULTS: BRMS1 protein expression was lost in nearly 25% of cases. Patients with tumors that were PR negative (P=0.006) or HER2 positive (P=0.039) and <50 years old at diagnosis (P=0.02) were more likely to be BRMS1 negative. No overall correlation between BRMS1 staining and disease-free survival was observed. A significant correlation, however, was seen between loss of BRMS1 protein expression and reduced disease-free survival when stratified by either loss of ER (P=0.008) or PR (P=0.029) or HER2 overexpression (P=0.026). Overall, there was poor correlation between BRMS1 protein staining and copy number status. CONCLUSIONS: These data suggest a mechanistic relationship between BRMS1 expression, hormone receptor status, and HER2 growth factor. BRMS1 staining could potentially be used in patient stratification in conjunction with other prognostic markers. Further, mechanisms other than genomic deletion account for loss of BRMS1 gene expression in breast tumors.  相似文献   
78.
A previously reported paradigm in which rats run down a runway for food reward followed by morphine injection was analyzed to assess the utility of the paradigm in studies of opiate reinforcement. One experiment replicated the original report that post-trial morphine caused both an increase in runway speed and a decrease in food consumption (taste aversion) over successive trials, and showed in addition that the increase in runway speed did not occur as a result of food deprivation alone, but required the animals to have consumed food in the goal box. A second study using the quaternary opiate antagonist methyl naltrexone to block the peripheral effects of morphine suggested that the increase in runway speed has a peripheral locus while the taste aversion has a central one. A third experiment in which morphine was microinjected into either the lateral ventricle or the ventral tegmental area supported these observations, in that intracranial morphine failed to result in an increased runway speed, but did produce taste aversion after microinjection into either site. These findings also suggest that the increase in runway speed caused by post-trial morphine in this experiment has a peripheral locus of effect, which is probably distinct from the central effect that supports morphine self-administration and conditioned place preference. Offprint requests to: W.A.CorrigallThe views expressed in this publication are those of the authors and do not necessarily reflect those of the Addiction Research Foundation  相似文献   
79.
Systemic anticancer therapy for hepatocellular carcinoma (HCC) is limited by intrinsic drug resistance and accompanying liver dysfunction. However, recent advances in molecular targeted therapy (MTT) have shed light on the treatment of advanced HCC. A recent randomized, placebo-controlled trial demonstrated that sorafenib, a multi-target tyrosine kinase inhibitor, prolonged overall survival and time-to-progression in patients with advanced HCC. This breakthrough highlights the potential of MTT targeting hepatocarcinogenic pathways, such as the Raf/MAPK/ERK pathway, angiogenic pathways and the EGFR signaling pathway. This review discusses the current status and the potential of developing novel MTTs for advanced HCC.  相似文献   
80.
The irritable bowel syndrome (IBS) is found more commonly in women than men. It is more prevalent in patients with chronic fatigue syndrome, fibromyalgia, and chronic pelvic pain, all syndromes characterized by pain and found predominantly in women. This article reviews evidence for a role of biological sex factors and gender on the pathways mediating visceral pain. The effect of gonadal hormones on gastrointestinal motility and the sensory afferent pathway and central processing of visceral stimuli and the contribution of gender role to the clinical presentation are discussed. Although differences in responses to treatment modalities between genders exist, the approach to IBS patients in both genders is quite similar. Nevertheless, a special attention to gender role and stress-related factors should be addressed. New developments in research, outlined in the paper, might bring more gender-specific treatments in the future.  相似文献   
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