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101.
We analyzed the presenting features and survival in 1689 patients with multiple myeloma aged younger than 50 years compared with 8860 patients 50 years of age and older. Of the total 10 549 patients, 7765 received conventional therapy and 2784 received high-dose therapy. Young patients were more frequently male, had more favorable features such as low International Staging System (ISS) and Durie-Salmon stage as well as less frequently adverse prognostic factors including high C-reactive protein (CRP), low hemoglobin, increased serum creatinine, and poor performance status. Survival was significantly longer in young patients (median, 5.2 years vs 3.7 years; P < .001) both after conventional (median, 4.5 years vs 3.3 years; P < .001) or high-dose therapy (median, 7.5 years vs 5.7 years; P = .04). The 10-year survival rate was 19% after conventional therapy and 43% after high-dose therapy in young patients, and 8% and 29%, respectively, in older patients. Multivariate analysis revealed age as an independent risk factor during conventional therapy, but not after autologous transplantation. A total of 5 of the 10 independent risk factors identified for conventional therapy were also relevant for autologous transplantation. After adjusting for normal mortality, lower ISS stage and other favorable prognostic features seem to account for the significantly longer survival of young patients with multiple myeloma with age remaining a risk factor during conventional therapy.  相似文献   
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Parental longevity is associated with an increased life expectancy; results with regard to specific diseases are conflicting. There are limited data focusing on host characteristics and their effect on survival among multiple myeloma (MM) patients and individuals with monoclonal gammopathy of undetermined significance (MGUS). Therefore, our aim was to evaluate the impact of parental longevity on survival of patients with MM and MGUS. A total of 4675 patients with MM, 6812 MGUS patients and 13 398 population-based controls for MM as well as 19 110 controls for MGUS, from 1988 to 2013, were included in the study. Longevity was defined as >90 years of age. Among MM patients, parental longevity was associated with a decreased risk of death [hazard ratio (HR) = 0·92, 95% confidence interval (CI) 0·84–0·99] and the same was true for MGUS patients (HR = 0·87, 95% CI 0·78–0·96). Having one long lived parent significantly decreased the risk of death in both groups, but was not statistically significant when both parents exceeded 90 years of age. In conclusion, parental longevity decreases the risk of death for patients with MM and MGUS which may reflect the importance of the host's genetic and environmental factors in relation to survival.  相似文献   
104.
To investigate the management of patients with community-acquired pneumonia (CAP) treated in hospital in Sweden, a multicentre retrospective cohort study was performed with medical record review of 982 patients (mean age 63 y) at 17 departments of infectious diseases at hospitals in Sweden. Information on antimicrobial therapy, demographic characteristics, comorbid conditions, physical examination findings, and laboratory and microbiological test results were recorded. Outcome measures were in-hospital mortality and length of hospital stay (LOS). Cultures were obtained from blood in 80% and from sputum in 22% of the patients. A microbiological aetiology was determined for 23% of the patients, with Streptococcus pneumoniae as the dominating agent (9%). The initial antibiotic treatment was mostly given intravenously (78%). Penicillin (50%) or a cephalosporin (30%) was the most common choice. Both of these drugs were usually given as a single agent. The overall mortality was 3.5% and the mean LOS was 6.4 d. Thus, the outcome was favourable despite the empirical antibiotic treatment having a narrow spectrum compared with the broader approach recommended in most recent guidelines on the management of CAP. These findings suggest that a majority of patients who are hospitalized with moderately severe pneumonia can be treated initially with penicillin alone.  相似文献   
105.
There are data to support a role for genetic and immune-related factors in the pathogenesis of lymphomas and plasma cell diseases. In this paper, we review our published large population-based studies and other relevant studies in Hodgkin’s and non-Hodgkin’s lymphomas, multiple myeloma, and the precursor condition monoclonal gammopathy of undetermined significance. We discuss the overlap in risk factors between related malignancies and explore the underlying mechanisms. Based on these studies, we provide clinical implications and discuss the relevance of these data for patient counseling and clinical follow-up. Finally, we suggest future directions for new studies designed to increase our current knowledge and to define underlying biological mechanisms of our findings.  相似文献   
106.
Steroids produced locally in brain (neurosteroids), including dehydroepiandrosterone (DHEA), influence cognition and behavior. We previously described a novel cytochrome P450, Cyp7b, strongly expressed in rat and mouse brain, particularly in hippocampus. Cyp7b is most similar to steroidogenic P450s and potentially could play a role in neurosteroid metabolism. To examine the catalytic activity of the enzyme mouse Cyp7b cDNA was introduced into a vaccinia virus vector. Extracts from cells infected with the recombinant showed NADPH-dependent conversion of DHEA (Km, 13.6 μM) and pregnenolone (Km, 4.0 μM) to slower migrating forms on thin layer chromatography. The expressed enzyme was less active against 25-hydroxycholesterol, 17β-estradiol and 5α-androstane-3β,17β-diol, with low to undetectable activity against progesterone, corticosterone, and testosterone. On gas chromatography and mass spectrometry of the Cyp7b metabolite of DHEA the retention time and fragmentation patterns were identical to those obtained with authentic 7α-hydroxy DHEA. The reaction product also comigrated on thin layer chromatography with 7α-hydroxy DHEA but not with 7β-hydroxy DHEA; when [7α-3H]pregnenolone was incubated with Cyp7b extracts the extent of release of radioactivity into the medium suggested that hydroxylation was preferentially at the 7α position. Brain extracts also efficiently liberated tritium from [7α-3H]pregnenolone and converted DHEA to a product with a chromatographic mobility indistinguishable from 7α-hydroxy DHEA. We conclude that Cyp7b is a 7α-hydroxylase participating in the synthesis, in brain, of neurosteroids 7α-hydroxy DHEA, and 7α-hydroxy pregnenolone.  相似文献   
107.
INTRODUCTION: The aim of this study was to analyze the block of HERG-carried membrane currents caused by H 345/52, a new antiarrhythmic compound with low proarrhythmic activity, in transfected mouse fibroblasts. METHODS AND RESULTS: Using the whole-cell configuration of the voltage patch clamp technique, it was demonstrated that H 345/52 concentration-dependently blocked HERG-carried currents with an IC50 of 230 nM. H 345/52 preferentially bound to the open channel with unusually rapid kinetics and was trapped by channel closure. Voltage-independent behavior of H 345/52 was observed during both square-pulse and action potential clamp protocols. In contrast, the Class III agents dofetilide (10 nM) and almokalant (250 nM) demonstrated significant membrane potential-dependent effects during square-pulse clamp protocols. When using action potential clamp protocols, voltage dependence was seen with dofetilide but not with almokalant. Mathematical simulations of human ventricular action potentials predicted that the different voltage-dependent behaviors would not produce marked variations in action potential duration prolongation patterns. CONCLUSION: We propose that block of IKr is the principal mechanism by which H 345/52 delays repolarization in human myocardium. The voltage independence of HERG/IKr block is unlikely to underlie the low proarrhythmic potential, and ancillary effects on other membrane currents must be considered.  相似文献   
108.
109.
The objective of this study is to validate two abridged versions of the mini-mental state examination (MMSE): one intended for use in face-to-face interviews, and the other developed for telephonic interviews, using data from Sweden and the US to validate the abridged scales against dementia diagnoses as well as to compare their performance to that of the full MMSE scale. The abridged versions were based on eight domains from the original MMSE scale. The domains included in the MMSE-SF were registration, orientation, delayed recall, attention, and visual spatial ability. In the MMSE-SF-C, the visual spatial ability item was excluded, and instead, one additional orientation item was added. There were 794 participants from the Swedish HARMONY study [mean age 81.8 (4.8); the proportion of cognitively impaired was 51 %] and 576 participants from the US ADAMS study [mean age 83.2 (5.7); the proportion of cognitively impaired was 65 %] where it was possible to compare abridged MMSE scales to dementia diagnoses and to the full MMSE scale. We estimated the sensitivity and specificity levels of the abridged tests, using clinical diagnoses as reference. Analyses with both the HARMONY and the ADAMS data indicated comparable levels of sensitivity and specificity in detecting cognitive impairment for the two abridged scales relative to the full MMSE. Receiver operating characteristic curves indicated that the two abridged scales corresponded well to those of the full MMSE. The two abridged tests have adequate validity and correspond well with the full MMSE. The abridged versions could therefore be alternatives to consider in larger population studies where interview length is restricted, and the respondent burden is high.  相似文献   
110.
The two estrogen receptor isoforms ERα and ERβ mediate biological effects of estrogens, but are also targets for endocrine disruptive chemicals (EDCs), compounds that interfere with hormonal signaling. 3-Methylcholanthrene (3-MC) and dioxin (TCDD) are EDCs and prototypical aryl hydrocarbon receptor (AhR) agonists, and can inhibit ER signaling. However, in contrast to TCDD, 3-MC gives rise to metabolites with estrogenic properties. We compared gene expression profiles in HepG2 cells after exposure to 3-MC, TCDD, and the synthetic estrogen diethylstilbestrol (DES). Interestingly, we observed little overlap between the genetic networks activated by 3-MC and TCDD, two compounds sometimes considered as interchangeable AhR ligands. Like DES, 3-MC induced a number of ER-regulated genes and lead to recruitment of ERα to the promoters of such genes. Interestingly, in contrast to DES, the estrogenic effects exerted by 3-MC were exclusively observed in ERα, but not in ERβ-expressing cells, suggesting ER isoform selectivity of 3-MC-derived metabolites.  相似文献   
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