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31.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
32.
Sweets, chocolate, and atypical depressive traits 总被引:1,自引:0,他引:1
An original questionnaire, the Foods and Moods Inventory (FMI) was used to investigate appetite for sweets and chocolate and its relationship to dysphoric mood. The FMI was administered to a group of subjects with an identified interest in chocolate (chocolate group, N = 73), a comparison sample (comparison group, N = 172), and a sample of former alcoholics (N = 22). Those who reported "self-medicating" with sweets or chocolate were more likely to have personality traits associated with hysteroid dysphoria, an atypical depressive syndrome. In addition, the tendency to eat compulsively, in general, and appetite for sweets and chocolate, in particular, were significantly greater among women. 相似文献
33.
目的:应用微乳液反应法制备磺胺嘧啶银均匀微晶,均匀制得的微晶的粒径大小约为2~4um,均匀微晶的结晶性好,纯度高。用均匀设计方法优化条件,制备的均匀的微晶平均粒径大小为2.09um,实验结果达到预测结果要求。结论:用微乳液反应法能获得磺胺嘧啶银均匀微晶。 相似文献
34.
微乳液反应法制备磺胺嘧啶银均匀微晶及其质量评价 总被引:1,自引:0,他引:1
目的:应用微乳液反应法制备磺胺嘧啶银均匀微晶,并评价其质量。方法:利用磺胺嘧啶钠微乳和硝酸银微乳混合后反应的方法,制备磺胺嘧啶银均匀微晶,用透射电镜观察其形态和大小,以X-射线衍射分析、红外光谱、核磁共振、差热分析等手段检测磺胺嘧啶银均匀微晶各种理化特性。结果:磺胺嘧啶银均匀微晶的粒径大小约为2~4μm,均匀微晶的结晶性好,纯度高。体外抑菌实验表明该品比市售磺胺嘧啶银具有更好的抑菌效果。结论:用微乳液反应法能获得磺胺嘧啶银均匀微晶。 相似文献
35.
Brain metabolic changes in major depressive disorder from pre- to post-treatment with paroxetine 总被引:5,自引:0,他引:5
Brody AL Saxena S Silverman DH Alborzian S Fairbanks LA Phelps ME Huang SC Wu HM Maidment K Baxter LR 《Psychiatry research》1999,91(3):127-139
Functional brain imaging studies of subjects with Major Depressive Disorder (MDD) have suggested that decreased dorsolateral (DLPFC) and increased ventrolateral (VLPFC) prefrontal cortical activity mediate the depressed state. Pre- to post-treatment studies indicate that these abnormalities normalize with successful treatment. We performed [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) scans on 16 outpatients with MDD before and after treatment with paroxetine (target dose = 40 mg/day). Regions of interest (ROIs) for this analysis were drawn by a rater blind to subject identity on the magnetic resonance image of each subject and transferred onto their coregistered PET scans. We hypothesized that DLPFC metabolism would increase, while ventral frontal metabolism [in the VLPFC, the orbitofrontal cortex (OFC), and the inferior frontal gyrus (IFG)] would decrease with successful treatment. Treatment response was defined as a decrease in the Hamilton Depression Rating Scale of > 50% and a Clinical Global Improvement Scale rating of 'much' or 'very much' improved. By these criteria, nine of the subjects were classified as treatment responders. These responders had significantly greater decreases in normalized VLPFC and OFC metabolism than did non-responders. There were no significant effects of treatment response on change in the DLPFC or IFG in this sample. However, there was a positive correlation between change in HAM-D scores and change in normalized IFG and VLPFC metabolism. There were no significant interactions with laterality. On pre-treatment scans, lower metabolism in the left ventral anterior cingulate gyrus was associated with better treatment response. These findings implicate ventral prefrontal-subcortical brain circuitry in the mediation of response to serotonin reuptake inhibitors in MDD. 相似文献
36.
As a consequence of the NHS reforms, the budgeting and competitive tendering of clinical services between districts requires accurate accumulation of data. John Mosley and Roger Fairbanks describe how data obtained by clinicians from their own audit has been used to construct a casemix solution that provides the necessary financial information for a district. 相似文献
37.
Economic costs of functional dyspepsia 总被引:5,自引:0,他引:5
Dyspepsia is defined as chronic or recurrent symptoms believed to originate in the upper gastrointestinal tract. When routine investigation results in no identifiable explanation for those symptoms patients are labelled as having functional dyspepsia. In community-based surveys, approximately 30% of the otherwise apparently healthy population report dyspeptic symptoms and the majority are believed to have functional dyspepsia. Although only 1 in 4 or 5 patients make use of healthcare resources, this patient category is one of the largest in ambulatory care (1.6 to 5% of all consultations in general practice). The annual frequency of consultations for functional dyspepsia in Sweden has been estimated at 47 per 1000 population. In consequence of its high prevalence and associated absenteeism, the total costs of functional dyspepsia are considerable. In Sweden in 1981, the costs were estimated at $US55 000 per 1000 population ($US113 630 in 1991 dollars). The most cost-effective management strategy remains to be defined. Evidence is accumulating that the traditional 'wait-and-see' policy with initial empirical therapeutic trials without investigation may not be the most cost conserving strategy. 相似文献
38.
McGuire M Bakst K Fairbanks L McGuire M Sachinvala N von Scotti H Brown N 《The Journal of nervous and mental disease》2000,188(12):813-817
We describe the design and development of the Cognitive Evaluation Protocol (CEP), a computer software program for evaluating cognitive and functional capacities and mood. The program is self-administered by subjects using touchscreen monitors for input. Stimuli in CEP subtests are randomized to reduce the effects of learning on repeated assessments. Findings demonstrate that a) minimum instruction is required for touchscreen use, even for computer-naive subjects; c) both normative subjects and psychiatric patients respond positively to self-administered evaluations; and c) CEP can be used for within-subject repeated evaluations with minimal distortion of results due to practice effects. The CEP Report Generator provides immediate printed performance results and creates a database for long-term digital storage and information use. 相似文献
39.
The involvement of the proliferating cell nuclear antigen (PCNA) in the
process of DNA repair induced by alkylating agents or by oxidative damage
was investigated in human quiescent fibroblasts by immunofluorescence and
flow cytometry. Transition from soluble to the DNA-bound form of PCNA, was
taken as the parameter to determine its involvement in repair DNA
synthesis. Treatment with the alkylating agents methylmethane sulfonate and
N-methyl-N'-nitro-N-nitrosoguanidine resulted in the rapid and
dose-dependent increase in the nuclear binding of PCNA. Similar results
were obtained with compounds such as hydrogen peroxide or tert-butyl
hydroperoxide, which are known to induce oxidative DNA damage. Tert-butyl
hydroperoxide may also generate malondialdehyde through a reaction of lipid
peroxidation. This mutagenic and carcinogenic product has been previously
shown to form adducts with DNA. Therefore, the possibility that tert-butyl
hydroperoxide could induce DNA damage through this pathway was investigated
by incubating cells directly in the presence of malondialdehyde. Such
treatment resulted in an increase in immunofluorescence associated with
nuclear-bound PCNA. The ability of oxidative and alkylating agents to
induce the nuclear binding of PCNA was also assessed in proliferating
cells. In these conditions, treatment with hydrogen peroxide or
methylmethane sulfonate, resulted in an increase in nuclear-bound PCNA in
the G1 and in the G2 + M compartments, but not in S phase. At longer times
after treatment, PCNA immunostaining was reduced to basal levels, while an
increase in nuclear binding of p21(waf1/cip1) protein was found in
concomitance with cell-cycle arrest. These results indicate that agents
inducing DNA base alterations in vivo, promote the nuclear binding of PCNA.
These lines of evidence support the role of a PCNA-dependent reaction in
the base excision repair system.
相似文献
40.
Hansen LA; Malarkey DE; Wilkinson JE; Rosenberg M; Woychik RE; Tennant RW 《Carcinogenesis》1998,19(10):1837-1845
We previously reported that papillomas can arise from the follicular
epithelium of v-Ha-ras transgenic TGxAC mice. Since the viable-yellow
mutation (A(vy)) of the mouse agouti gene which regulates coat color
pigmentation by acting within the micro-environment of the hair follicle
has been shown to function as a tumor promoter in the liver, we
hypothesized that it may also play a role in TGxAC skin tumorigenesis.
Endogenous agouti protein product was detected in the outer root sheath of
anagen hair follicles following plucking of the hair shaft, but not in the
interfollicular epithelium, in TGxAC mice on an FVB/N genetic background.
It was also detected in papillomas from these mice produced by
12-O-tetradecanoylphorbol-13-acetate (TPA) treatment or plucking.
Expression of the A(vy) allele in the v-Ha-ras transgenic TGxAC mouse line
results in an approximately 2-fold increase in papilloma development
compared with controls which did not carry the A(vy) allele following
twice-weekly treatment with 1.25, 2.5 or 5.0 microg TPA. In addition,
TPA-treated, papilloma-bearing F1 mice which carried the A(vy) allele, but
not F1 mice which did not carry the A(vy) allele, exhibited a syndrome of
humoral hypercalcemia mediated by parathyroid hormone-related protein
(PTHrP) that led to weight loss, hypercalcemia and hypophosphatemia. Thus,
we conclude that the A(vy) allele can influence the development of skin
tumors and PTHrP-mediated humoral hypercalcemia in v-Ha-ras transgenic
TGxAC mice.
相似文献