PubMed Health⌕ Search

Biomedical subjects

N Silverberg

Publications and source records attributed to N Silverberg.

5 recordsLinked to original sources
PubMed2005

Is the functional decline of Parkinson's disease similar to the functional decline of Alzheimer's disease?

Since many Parkinson's disease (PD) subjects develop dementia, we determined whether the correlation between functional and cognitive decline seen in Alzheimer's disease (AD) is seen in PD. Seventy-five PD subjects with and without dementia and 103 AD/MCI subjects underwent the Functional Assessment Staging (FAST), the Global Deterioration Scale (GDS), the UPDRS motor portion, and the MMSE. In AD/MCI subjects, changes in FAST and GDS scores correlated with MMSE (rho=-0.814, P<0.001; rho=-0.840, P<0.001, respectively). In PD subjects, the FAST and GDS also correlated with MMSE (rho=-0.675, P<0.001; rho=-0.647, P<0.001, respectively). The UPDRS correlated with the GDS and FAST more closely in PD than in AD. Similar to AD, functional declines in PD correlates with cognitive decline and may be influenced by motor disability in PD.

Activities of Daily Living↗
PubMed2003

Cognitive decline in high-functioning older adults: reserve or ascertainment bias?

The detection of mild cognitive impairment and dementia in high-functioning older adults can be difficult. It has also been observed that high-functioning persons show a lower prevalence of dementia than low-functioning persons. Three alternative explanations for this observation have been proposed in the literature: brain reserve capacity (BRC), cognitive reserve, and ascertainment bias. With data from a prospective, population-based study of incident dementia, the Canadian Study of Health and Aging (CSHA), we classified participants as being high- (HF) or low-functioning (LF) in three ways: educational and occupational attainment, and estimated premorbid IQ. We observed that fewer HF older adults were diagnosed with dementia after five years, which is in accordance with both the BRC and cognitive reserve models. Contrary to expectations, no difference on rate of memory deterioration was observed between those HF and LF persons who exhibited mild cognitive impairment at CSHA-1. However, HF persons who subsequently were diagnosed with dementia (CSHA-2) showed more rapid decline on five of the six memory measures over time than did LF persons diagnosed with dementia at CSHA-2. When performance on measures of memory functioning at CSHA-1 was examined for highly educated older adults, significantly more of those with dementia at CSHA-2 (n = 59) had scores falling within or below the average range in comparison to normative standards than those who continued to show no cognitive impairment (n = 145). Our findings suggest that the lower incidence of dementia for HF persons may be primarily the result of ascertainment bias, not underlying differences in brain or cognitive reserve.

Activities of Daily Living↗
PubMed1996

Vertical Flux of Biogenic Carbon in the Ocean: Is There Food Web Control?

Models of biogenic carbon (BC) flux assume that short herbivorous food chains lead to high export, whereas complex microbial or omnivorous food webs lead to recycling and low export, and that export of BC from the euphotic zone equals new production (NP). In the Gulf of St. Lawrence, particulate organic carbon fluxes were similar during the spring phytoplankton bloom, when herbivory dominated, and during nonbloom conditions, when microbial and omnivorous food webs dominated. In contrast, NP was 1.2 to 161 times greater during the bloom than after it. Thus, neither food web structure nor NP can predict the magnitude or patterns of BC export, particularly on time scales over which the ocean is in nonequilibrium conditions.

Journal Article↗
PubMed1989

Aging and the skin.

Several pathologic processes of the skin are seen more commonly in the elderly, so these patients need special attention. The skin undergoes physiologic and structural changes as it ages, and knowledge of these changes is essential to accurately interpret the physical signs and symptoms that may be present in the elderly patient. Since cutaneous inflammatory responses and subjective sensations may be diminished in aged skin, a higher degree of vigilance in physical examination is needed to reach a proper diagnosis. Prevention of many of the cutaneous signs of aging and of most skin cancers is dependent upon sun avoidance. Thus, the best advice physicians can offer patients of any age is to limit sun exposure by using a sunscreen with a high sun-protection factor, to avoid being in the sun during the peak tanning hours (between 10:00 AM and 2:00 PM), and to wear protective clothing when exposed to the sun.

Aged↗