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Not Necessary (not + necessary)
Selected AbstractsMemory Complaint Is Not Necessary for Diagnosis of Mild Cognitive Impairment and Does Not Predict 10-Year Trajectories of Functional Disability, Word Recall, or Short Portable Mental Status Questionnaire LimitationsJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 2 2006Jama L. Purser PhD OBJECTIVES: To evaluate the prevalence and utility of memory complaint in a geographically representative cohort and, in cases with mild cognitive impairment (MCI), to determine whether memory complaint alters 10-year trajectories of disability in activities of daily living (ADLs), Short Portable Mental Status Questionnaire (SPMSQ) score, and 20-item word recall. DESIGN: Prospective cohort study. SETTING: Washington and Iowa counties, Iowa. PARTICIPANTS: Iowa Established Populations for Epidemiologic Studies of the Elderly (N=3,673; aged ,65; 61.3% female; 99.9% white). MEASUREMENTS: Age, sex, education, SPMSQ score, 20-item word recall, ADL or instrumental ADL disability, and chronic medical conditions. RESULTS: The prevalence of memory complaint was 34%. Although proportionally more cognitively impaired individuals were in the memory complaint group (34% vs 27%), the pattern of subclassification into cognitively intact and MCI Stage 1 and 2 subgroups was similar for people with and without memory complaint. Median SPMSQ score and number of words recalled at baseline were comparable across memory complaint categories in each subgroup. MCI participants without subjective memory complaint constituted a larger proportion of the overall sample than individuals with subjective memory complaint (460 (14%) vs 295 (8.9%)) and of persons objectively classified as having MCI (61% vs 39%). The distribution of individual 10-year change in ADL disability, SPMSQ score, and word recall were similar for those with and without memory complaint across all subgroups of cognitive impairment. CONCLUSION: Memory complaint is not necessary for MCI diagnosis and does not distinguish cases with different progression rates in disability or cognitive impairment. 2006. [source] Research Article: The Cysteine Pairs in CLV2 are Not Necessary for Sensing the CLV3 Peptide in Shoot and Root MeristemsJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 9 2010Xiufen Song Receptor-like proteins (RLPs) are involved in both plant defense and developmental processes. Previous genetic and biochemical studies show that the leucine-rich repeat (LRR) receptor-like protein CLAVATA2 (CLV2) functions together with CLAVATA1 (CLV1) and CORYNE (CRN) in Arabidopsis to limit the stem cell number in shoot apical meristem, while in root it acts with CRN to trigger a premature differentiation of the stem cells after sensing the exogenously applied peptides of CLV3p, CLE19p or CLE40p. It has been proposed that disulfide bonds might be formed through two cysteine pairs in the extracellular LRR domains of CLV1 and CLV2 to stabilize the receptor complex. Here we tested the hypothesis by replacing these cysteines with alanines and showed that depletions of one or both of the cysteine pairs do not hamper the function of CLV2 in SAM maintenance. In vitro peptide assay also showed that removal of the cysteine pairs did not affect the perception of CLV3 peptides in roots. These observations allow us to conclude that the formation of disulfide bonds is not needed for the function of CLV2. [source] Daily Meal Timing is Not Necessary for Resetting the Main Circadian Clock by Calorie RestrictionJOURNAL OF NEUROENDOCRINOLOGY, Issue 2 2008J. Mendoza In rodents, entrainment and/or resetting by feeding of the central circadian clock, the suprachiasmatic nucleus (SCN), is more efficient when food cues arise from a timed calorie restriction. Because timed calorie restriction is associated with a single meal each day at the same time, its resetting properties on the SCN possibly depend on a combination of meal time-giving cues and hypocaloric conditions per se. To exclude any effect of daily meal timing in resetting by calorie restriction, the present study employed a model of ultradian feeding schedules, divided into six meals with different durations of food access (6 × 8-min versus 6 × 12-min meal schedule) every 4 h over the 24-h cycle. The effects of such an ultradian calorie restriction were evaluated on the rhythms of wheel-running activity (WRA) and body temperature (Tb) in rats. The results indicate that daily/circadian rhythms of WRA and Tb were shifted by a hypocaloric feeding distributed in six ultradian short meals (i.e. 6 × 8-min meal schedule), showing both phase advances and delays. The magnitude of phase shifts was positively correlated with body weight loss and level of day-time behavioural activity. By contrast, rats fed daily with six ultradian meals long enough (i.e. 6 × 12-min meal schedule) to prevent body weight loss, showed only small, if any, phase shifts in WRA and Tb rhythms. The results obtained reveal the potency of calorie restriction to reset the SCN clock without synchronisation to daily meal timing, highlighting functional links between metabolism, calorie restriction and the circadian timing system. [source] Donor Fas Is Not Necessary for T-Cell-Mediated Rejection of Mouse Kidney AllograftsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 10 2008D. Kayser It is important to resolve whether T-cell-mediated rejection (TCMR) is mediated by contact-dependent cytotoxicity or by contact-independent inflammatory mechanisms. We recently showed that the cytotoxic molecules perforin and granzymes A and B are not required for TCMR of mouse kidney transplants. Nevertheless, TCMR could still be mediated by cytotoxicity via Fas on donor cells engaging Fas ligand on host T cells. We examined whether the diagnostic TCMR lesions would be abrogated if donor Fas was absent, particularly in hosts deficient in perforin or granzymes A and B. Kidneys from Fas-deficient donors transplanted into major histocompatibility complex (MHC)- mismatched hosts developed tubulitis and diffuse interstitial infiltration indistinguishable from wild-type (WT) allografts, even in hosts deficient in perforin and granzymes A and B. Gene expression analysis revealed similar molecular disturbances in Fas-deficient and WT allografts at day 21 transplanted into WT, perforin and granzyme A/B-deficient hosts, indicating epithelial injury and dedifferentiation. Thus, donor Fas is not necessary for TCMR diagnostic lesions or molecular changes, even in the absence of perforin,granzyme mechanisms. We propose that in TCMR, interstitial effector T cells mediate parenchymal injury by inflammatory mechanisms that require neither the perforin,granzyme nor the Fas,Fas ligand cytotoxic mechanisms. [source] | ||||||||||