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1.
Phantana-angkool April Voci Amy E. Warren Yancey E. Livasy Chad A. Beasley Lakesha M. Robinson Myra M. Hadzikadic-Gusic Lejla Sarantou Terry Forster Meghan R. Sarma Deba White Richard L. 《Annals of surgical oncology》2019,26(12):3874-3882
Annals of Surgical Oncology - The role of sentinel lymph node biopsy (SLNB) when ductal carcinoma in situ with microinvasion (DCISM) is identified on core biopsy is unclear. Our aim was to assess... 相似文献
2.
Rachel A. Woolrich Myra J. Cooper Hannah M. Turner 《Cognitive therapy and research》2006,30(6):735-748
Objective: The study explored the semantic content and origins of negative self-beliefs, and their functional links to “not eating enough” and other behaviors, in participants with anorexia nervosa (AN). Method: Fifteen women meeting DSM-IV criteria for AN were compared with 17 dieting and 18 non-dieting women matched on age and number of years of education. The main outcome measure was a semi-structured interview. Results: Six themes were identified in the beliefs of participants with AN. These were, in order of decreasing frequency, powerlessness (present in all but three AN participants), failure, defectiveness, unattractiveness, worthlessness and emptiness. Importantly, powerlessness and failure beliefs were consistently present independent of Beck Depression Inventory-II scores. The negative early life experiences associated with these beliefs had high distress and responsibility ratings. Participants with AN reported that they employed specific behaviors, particularly ‘not eating enough,’ and ‘placating others,’ to try to reduce the cognitive and emotional impact of their negative self-beliefs. Discussion: The findings are discussed in relation to the role of powerlessness and the function of “not eating enough” in cognitive theory and therapy for AN.
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Chemiluminescent and flow cytometric analysis of gamma interferon preincubation on neonatal and adult rat polymorphonuclear leukocytes.
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R R Wittler M M Lieberman D D Paine S L Muehlbauer J E Lima D M Sachanandani C A Pinney 《Clinical and Vaccine Immunology : CVI》1996,3(5):527-532
Gamma interferon (IFN-gamma) has multiple immunomodulating effects and has been postulated as a possible immunopotentiating agent for the prevention or treatment of neonatal infections. This report describes the effect of rat recombinant IFN-gamma on the oxidative burst activity and CD11b expression of neonatal and adult rat polymorphonuclear leukocytes (PMNL). Oxidative burst activity was assessed by chemiluminescence and dihydrorhodamine flow cytometry. Neonatal PMNL exhibited significantly less oxidative burst activity than did adult PMNL. IFN-gamma mildly enhanced the chemiluminescence response of PMNL from both the rat pups and adults, but this effect was not statistically significant when analyzed by a multivariate model of repeated-measures analysis of variance for both chemiluminescence and dihydrorhodamine flow cytometry. CD11b expression was also not significantly enhanced by IFN-gamma. 相似文献
6.
Three structurally related compounds, 4-acetoxy-3-acetoxy-methyl-acetophenone(AAMAP), 1-[4'- hydroxy-3'-hydroxy-methylphenyl]-2-[benzyl-t-butylamino]ethanone hydrochloride (HHBEH) and 1-[4'-hydroxy-3'-hydroxymethyl-phenyl]-2-[benzyl-t-butylamino]ethanol (HHBE), gave positive dose-related mutagenic responsesin the Ames test when Salmonella typhimurium strain TA100 wasused as the test organism. Strain TA100 carries the hisG46 allele,which is revertable by base changes, together with plasmid pKM101,which encodes mucAB genes that are analogous to umuDC, the chromosomalSOS-repair genes of Escherichia coli K-12. None of the compoundswas mutagenic in Ames strain TA1535, which is the plasmid-freederivative of strain TA100. Only AAMAP, and that at only thehighest concentration tested, was mutagenic in strain TA98,which detects frameshift mutations and carries plasmid pKM101.No compound was significantly mutagenic in strain TA1538, whichis the plasmid-free derivative of strain TA98. When the threecompounds were tested for the induction of sister-chromatidexchanges (SCEs) in Chinese hamster cells, the two more potentmutagens, AAMAP and HHBEH were found to increase SCEs, whereasHHBE did not give a significant response at any concentrationtested. Ames test data showing plasmid pKM101-dependent mutagenesisare therefore, at least for these compounds, relevant indicatorsof eukaryotic genotoxicity.
Parts of this paper were communicated to the Science Group atthe 123rd British Pharmaceutical Conference, Jersey, 1986. 相似文献
7.
Molecular identification of a novel deltaproteobacterium as the etiologic agent of epizootic bovine abortion (foothill abortion)
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King DP Chen CI Blanchard MT Aldridge BM Anderson M Walker R Maas J Hanks D Hall M Stott JL 《Journal of clinical microbiology》2005,43(2):604-609
Epizootic bovine abortion (EBA) is endemic in California's coastal range and the foothill regions of the Sierra Nevada, where it has been the primary diagnosed cause of abortion in beef cattle for >50 years. Investigation of these losses has defined a specific fetal syndrome characterized by late-term abortion or birth of weak or dead calves. Although the unusual clinical presentation and unique fetal pathology associated with EBA have been recognized since the 1950s, the identity of the etiologic agent is unknown. In this study, suppression-hybridization PCR was used to identify a fragment of the 16S rRNA gene of a previously undescribed bacterium in thymus tissue derived from affected fetuses. Phylogenetic analysis revealed that this pathogen was a deltaproteobacterium closely related to members of the order Myxococcales. A specific PCR was subsequently developed to detect the presence of this bacterium in DNA extracted from fetal thymuses. Using histopathology as the definitive diagnosis for EBA, this PCR demonstrated 100% specificity and 88% sensitivity. The bacterium was also detected in the argasid tick Ornithodoros coriaceus, which is the recognized vector of EBA. These data imply a close association between this novel agent and the etiology of EBA. 相似文献
8.
Germline mutations of the CDKN2 gene in UK melanoma families 总被引:4,自引:1,他引:4
Harland M; Meloni R; Gruis N; Pinney E; Brookes S; Spurr NK; Frischauf AM; Bataille V; Peters G; Cuzick J; Selby P; Bishop DT; Bishop JN 《Human molecular genetics》1997,6(12):2061-2067
Germline mutations in CDKN2 on chromosome 9p21, which codes for the cyclin
D kinase inhibitor p16, and more rarely, mutations in the gene coding for
CDK4, the protein to which p16 binds, underlie susceptibility in some
melanoma families. We have sequenced all exons of CDKN2 and analysed the
CDK4 gene for mutations in 27 UK families showing evidence of
predisposition to melanoma. Five different germline mutations in CDKN2 were
found in six families. Three of the mutations (Met53Ile, Arg24Pro and
23ins24) have been reported previously. We have identified two novel CDKN2
mutations (88delG and Ala118Thr) which are likely to be associated with the
development of melanoma, because of their co-segregation with the disease
and their likely functional effect on the CDKN2 protein. In binding assays
the protein expressed from the previously described mutation, Met53Ile, did
not bind to CDK4/CDK6, confirming its role as a causal mutation in the
development of melanoma. Ala118Thr appeared to be functional in this assay.
Arg24Pro appeared to bind to CDK6, but not to CDK4. No mutations were
detected in exon 2 of CDK4, suggesting that causal mutations in this gene
are uncommon. The penetrance of these mutant CDKN2 genes is not yet
established, nor is the risk of non-melanoma cancer to gene carriers.
相似文献
9.
Detection of HIV-1 antiretroviral resistance from patients with persistently low but detectable viraemia 总被引:3,自引:0,他引:3
We modified the Abbott diagnostics HIV-1 Viroseq version 2 assay trade mark in order to detect the presence of HIV-1 drug resistance mutations in patients with viraemia below 1000 copies/ml of plasma. One hundred and forty-four patients with a detectable HIV-1 plasma viral load below 1000 copies/ml were selected and HIV-1 genetic analysis carried out using a modification of the Abbott Diagnostics Viroseq 2.0 assay trade mark. The procedure differs from the standard protocol in that a nested PCR amplification step was introduced. The oligonucleotide primers for the first round of PCR were those supplied in the RT-PCR module of the kit. The nested PCR primers were primers A and H taken from the sequencing module. One hundred and twenty-eight out of 144 (89%) plasma samples with an HIV-1 viral load of less than 1000 copies/ml (ranging from 54 to 992 copies) were successfully sequenced. HIV-1 genotypes were obtained from 68 out of 81 (84%) samples with a viral load of greater than 50 but less than 300 copies/ml and 60/63 (95%) of samples with a viral load of greater than 300 but less than 1000 copies/ml. Serial dilution of a sample with a high viral load did not affect the detection of resistance mutations. Multiple sequencing of samples with low viral load did not result in detection of additional mutations, although, in one sample the K103N mutation was detected in 3/6 replicates while wild-type was detected in 2/6 and a mixture of wild-type/mutant in 1/6. Samples from patients infected with both clade B and non-B clades of HIV-1 could be genotyped at low copy number. Modification of the Abbott Viroseq assay allows reproducible sequencing of the HIV-1 genome from patients with low, but detectable, plasma virus burden. 相似文献
10.
In vitro evidence for participation of DEC-205 expressed by thymic cortical epithelial cells in clearance of apoptotic thymocytes 总被引:2,自引:0,他引:2
Binding of apoptotic cells was compared after incubation of thymocytes with two clones of murine thymic stromal cells to which CD4(+)/CD8(+) thymocytes attach. With the BA/10, but not the BA/2, clone, thymocytes with apoptotic morphology were bound irreversibly. These tightly bound thymocytes were further identified as apoptotic in terms of active caspase-3 and DNA fragmentation assayed in situ. FACS analysis indicated that the apoptotic thymocytes are at an early double-positive stage and results with mice mutant for the Fas gene showed that the Fas-Fas ligand system is not involved. Comparison of BA/10 and BA/2 cells showed that the former, but not the latter, can be induced to express CDR-1 antigen which is characteristic of cortical epithelial thymic stroma and constitutively express DEC-205, a surface protein common to cortical thymic epithelium and dendritic cells. Antibody NLDC-145 that is specific for the DEC-205 protein strongly reduced the number of stromal cells with bound apoptotic thymocytes. Preincubation of thymocytes in dexamethasone dramatically increased the number of bound apoptotic cells, indicating that the thymic cortical epithelial cells can participate in clearance of apoptotic thymocytes through involvement of DEC-205. 相似文献