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71.
Carol A Mathews Caroline M Nievergelt Amin Azzam Helena Garrido Denise A Chavira Jennifer Wessel Monica Bagnarello Victor I Reus Nicholas J Schork 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2007,(2):174-182
To date, only one complete genome screen for obsessive-compulsive disorder (OCD) has been published. That study identified a region of suggestive linkage (maximum lod score of 2.25) with a relatively small sample size (N = 56; 27 with OCD). Additional complete genome screens are needed to confirm this finding and identify other regions of linkage. We present the clinical characteristics and power to detect linkage of 11 multigenerational families with OCD and hoarding (N = 92; 44 with OCD), as well as heritability estimates for several quantitative traits. Families with at least two individuals with OCD were identified through probands with childhood-onset OCD. Expected lod scores were calculated for simulated genetic marker data under an additive and two dominant models assuming a dense SNP marker map. All affected individuals had an early age of onset (18 or younger). Hoarding was present in 46% of subjects. Obsessive-compulsive symptoms and hoarding were highly heritable. The maximum mean expected lod score was 3.31 for OCD and 1.39 for hoarding. We found reasonable power to detect regions of interest (lod = 2) for OCD in these families, but will need to expand our family collection to have adequate power to detect regions of interest for hoarding. 相似文献
72.
Grego E Profiti M Giammarioli M Giannino L Rutili D Woodall C Rosati S 《Clinical and diagnostic laboratory immunology》2002,9(4):828-832
The pol and gag gene fragments of small ruminant lentivirus field isolates collected in the last decade in Italy were amplified, sequenced, and analyzed. Phylogenetic analysis revealed that the majority of ovine isolates form a distinct cluster more similar to caprine lentivirus prototypes than to the visna virus prototype. These findings confirm and extend those reported by Leroux et al. (Arch. Virol., 142:1125-1137, 1997). Moreover, we observed that a variable region of Gag, included in the fragment analyzed, corresponded to one of the three major capsid antigen epitopes, which suggests that the antibody response to this epitope may be type specific. To test this hypothesis, two recombinant peptides, derived from the Icelandic prototype K1514 and this novel genotype, were expressed and used in an enzyme-linked immunosorbent assay to screen a panel of ovine and caprine sera collected from different geographical locations in Italy. Several sera reacted in a type-specific manner, indicating that in a diagnostic setting the combination of at least these two type-specific peptides is necessary to cover a wide range of infections. Additionally, these results support the hypothesis of cross-species transmission based on the phylogenetic analysis described above. This has implications for the control and eradication of small ruminant lentivirus infections. 相似文献
73.
Monica Rossi Enzo Ricci Luca Colantoni Giuliana Galluzzi Roberto Frusciante Pietro A Tonali Luciano Felicetti 《BMC medical genetics》2007,8(1):8
Background
The homologous 4q and 10q subtelomeric regions include two distinctive polymorphic arrays of 3.3 kb repeats, named D4Z4. An additional BlnI restriction site on the 10q-type sequence allows to distinguish the chromosomal origin of the repeats. Reduction in the number of D4Z4 repeats below a threshold of 10 at the 4q locus is tightly linked to Facioscapulohumeral Muscular Dystrophy (FSHD), while similar contractions at 10q locus, are not pathogenic. Sequence variations due to the presence of BlnI-sensitive repeats (10q-type) on chromosome 4 or viceversa of BlnI-resistant repeats (4q-type) on chromosome 10 are observed in both alleles. 相似文献74.
Differentiation of Cucumber mosaic virus isolates by hybridization to oligonucleotides in a microarray format 总被引:5,自引:0,他引:5
Deyong Z Willingmann P Heinze C Adam G Pfunder M Frey B Frey JE 《Journal of virological methods》2005,123(1):101-108
A system for microarrays was developed to detect and differentiate Cucumber mosaic virus (CMV) serogroups and subgroups. The coat protein genes of 14 different isolates were amplified using cy3-labelled generic but species-specific primers. These amplicons were hybridized against a set of five different serotype and subgroup specific 24-mer oligonucleotides bound to an aldehyde-coated glass slide via an aminolinker. The results of the hybridization revealed that the method allowed a clear differentiation of the 14 different CMV isolates into the serogroupes 1 and 2, and in addition was able to assign 9 out of 10 different serogroup 1 isolates correctly into subgroups 1a and 1b. This differentiation was not possible by RFLP analysis with the restriction enzyme MspI. The use of amplicons larger than 700 base pairs and their successful differentiation by hybridization to specific oligonucleotides opens avenues to highly parallel, yet sensitive assays for plant viruses. 相似文献
75.
76.
Human cancer is an unpredictable disease as is its response to therapy. The intrinsic genetic heterogeneity and instability
of cancer cells could in part explain such behavior. However, it is possible that, individual variation in the genetic make-up
of humans may affect the relationship between host and cancer cells and, therefore, be, at least in part responsible for this
extraordinary variation. Human gene polymorphism has been shown indeed to play a role in immune responses; among the immune-related
genes, cytokines are often polymorphic. Some polymorphisms of cytokine and cytokine receptor may have direct functional significance
by altering directly and indirectly the level of gene expression and/or its function; other may only demarcate a genetic linkage
to a particular haplotype associated with a given clinical condition. The majority of polymorphisms found in cytokines or
their receptors are located in the promoter, intronic and 3′ untranslated regions. These sequence variations can still affect
gene expression and function. In this review will we summarize the current knowledge about the role of cytokine polymorphism
in disease and more specifically in cancer. 相似文献
77.
A one-year follow-up on the effects of raloxifene on thyroid function in postmenopausal women 总被引:5,自引:0,他引:5
Ceresini G Morganti S Rebecchi I Bertone L Ceda GP Bacchi-Modena A Sgarabotto M Baldini M Ablondi F Valenti G Braverman LE 《Menopause (New York, N.Y.)》2004,11(2):176-179
OBJECTIVE: Estrogens increase serum thyroxine-binding globulin (TBG) and total thyroxine (TT4) concentrations. Serum free thyroxine (FT4) concentrations, however, remain normal. Raloxifene (RAL) is a selective estrogen receptor modulator used to treat postmenopausal osteoporosis. Data on the long-term effects of RAL on thyroid physiology are scanty. We evaluated the effects of RAL administration for 1 year on thyroid function in osteopenic, postmenopausal women. DESIGN: Fifty osteopenic, postmenopausal women were randomly assigned to receive either RAL (60 mg/day, n = 25) or placebo (PL, n = 25) for 1 year, in a double-blind study. Measurements of serum TBG, TT4, FT4, thyroid-stimulating hormone (TSH), thyroid hormone-binding ratio (THBR), FT4 index (FT4-I) and TT4/TBG ratio were carried out at baseline and after 4 and 12 months of therapy. RESULTS: Baseline values were similar in both treatment groups. Serum TBG concentrations were increased during RAL treatment from baseline values of 29.60 +/- 0.9 microg/mL to 31.45 +/- 1.33 and 32.34 +/- 1.37 microg/mL at 4 months and 1 year, respectively (P < 0.05, baseline v 1-year values) but were unchanged during PL treatment. A small, insignificant increase in TT4 and TSH concentrations occurred in the RAL group and no changes in the PL group. All other values were unchanged during either treatment. CONCLUSIONS: These results demonstrate that RAL significantly increased serum TBG levels, but the changes were small and not accompanied by changes in FT4-I, FT4, or TSH concentrations, suggesting that long-term RAL treatment is unlikely to clinically affect the thyroid status in euthyroid, postmenopausal women. 相似文献
78.
Strategic control and medial frontal negativity: beyond errors and response conflict 总被引:6,自引:0,他引:6
Errors in timed choice tasks typically produce an error-related negativity (ERN) in the event-related potential (ERP). The error specificity of the ERN has been challenged by studies showing a correct response negativity (CRN). Forty-five participants engaged in a flanker task in which both compatibility between flankers and target and the probability of compatible flankers were manipulated. Correct responses elicited a CRN, the amplitude of which increased with the degree of mismatch between the presence of conflict and conflict probability, even on low-conflict (compatible) trials. The fronto-central N2 component was larger on high-conflict (incompatible) correct response trials. However, in contrast to some recent accounts, this N2 was largest for highly probable stimuli. These findings suggest revision to models of the effects of conflict on response-related negativity to account for strategic adjustments made in preparation for the response. 相似文献
79.
Leonard A. Jason Steven B. Pokorny Mazna Patka Monica Adams Taylor Morello 《Journal of community psychology》2007,35(8):967-979
Two primary outlets for community psychology research, the American Journal of Community Psychology and the Journal of Community Psychology, were assessed to rank institutions based on publication frequency and scientific influence of publications over a 32‐year period. Three specific periods were assessed (1973–1983, 1984–1994, 1995–2004). Findings indicate that there were a large group of institutions that published articles during these periods. Those academic institutions that had the most published articles as well as the largest influence, based on citations by other authors, were identified. Using archival data from the community psychology literature represents one approach for identifying those settings that made substantial contributions to the development and growth of the field. © 2007 Wiley Periodicals, Inc. J Comm Psychol 35: 967–979, 2007. 相似文献
80.
Turell MJ O'Guinn ML Navarro R Romero G Estrada-Franco JG 《Journal of medical entomology》2003,40(3):306-310
Experimental studies evaluated the vector competence of Ochlerotatus taeniorhynchus (Wiedemann), Culex cancer Theobald, Culex pseudes (Dyar and Knab), Culex taeniopus Dyar and Knab, and a Culex (Culex) species, probably Culex quinquefasciatus Say, and Culex nigripalpus Theobald from Chiapas, Mexico, and Tocoa, Honduras, for epizootic (IC) and enzootic (IE) strains of Venezuelan equine encephalomyelitis (VEE) virus. Culex pseudes was highly susceptible to infection with both the IC and IE strains of VEE (infection rates >78%). Patterns of susceptibility to VEE were similar for Oc. taeniorhynchus collected in Mexico and Honduras. Although Oc. taeniorhynchus was highly susceptible to the epizootic IC strains (infection rates > or = 95%, n = 190), this species was less susceptible to the enzootic IE strain (infection rates < or = 35%, n = 233). The Culex (Culex) species were refractory to both subtypes of VEE, and none of 166 contained evidence of a disseminated infection. Virus-exposed Cx. pseudes that refed on susceptible hamsters readily transmitted virus, confirming that this species was an efficient vector of VEE. Although Oc. taeniorhynchus that fed on hamsters infected with the epizootic IC strain transmitted VEE efficiently, only one of six of those with a disseminated infection with the enzootic IE virus that fed on hamsters transmitted virus by bite. These data indicate that Cx. pseudes is an efficient laboratory vector of both epizootic and enzootic strains of VEE and that Oc. taeniorhynchus could be an important vector of epizootic subtypes of VEE. 相似文献