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Park DC, Nam HS, Lim SR, Lee PH, Heo JH, Lee BI, Kim DI. MRI features of infarcts with potential cardiac source of embolism in the Yonsei Stroke Registry (YSR), Korea. Yonsei Med J 2000; 41:431-5. [PMID: 10992802 DOI: 10.3349/ymj.2000.41.4.431] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The determination of the embolic source is crucial to understanding the pathogenesis of ischemic stroke, the initiation of appropriate therapy, and the prevention of recurrent infarctions. In this study we undertook to identify the characteristic features on magnetic resonance images of patients who had suffered from stroke due to cardiac embolism (CE), as classified by TOAST (possible and probable). We retrospectively studied magnetic resonance imaging (MRI) findings of patients with ischemic stroke from the Yonsei Stroke Registry (YSR). On the basis of the TOAST classification, 92 patients were identified to have a potential cardiac source of embolism (PCSE), in which 69 patients were found to have high-risk PCSE and 23 patients medium-risk PCSE. To compare their imaging characteristics, another group of 49 patients who were found to have had a stroke due to large artery-to-artery (ATA) embolism-common or internal carotid artery (CCA, ICA)-were identified. Involvement of the simultaneous superficial and deep territories (58.7%; 6.1%, p < 0.001), and combined new anterior and old posterior circulation (15.2%; 2.0%, p = 0.016) were more frequent in PCSE than ATA embolism. Bilateral anterior hemispheric involvement was also more frequent in the PCSE group, but it did not reach statistical significance (13.0%; 4.1%, p = 0.090). ATA embolism tended to involve only superficial territories compared to PCSE (71.4%; 28.3%, p < 0.001). There were no topographic differences between the high-risk and medium-risk groups. With respect to the etiology of PCSE in our population, atrial fibrillation was the most common. Characteristic MRI features of patients with PCSE, which were not documented previously by computed tomography (CT) included: old and new, involvement of multiple different vascular territories, bilateral anterior hemisphere, as well as anterior and posterior circulation. These MRI features, together with simultaneous superficial and deep territorial involvement, help to differentiate the underlying embolic sources, whether they are cardiac or ATA in origin.
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Shifren K, Park DC, Bennett JM, Morrell RW. Do cognitive processes predict mental health in individuals with rheumatoid arthritis? J Behav Med 1999; 22:529-47. [PMID: 10650535 DOI: 10.1023/a:1018782211847] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The purpose of the present study was to assess the hypothesis that intellectual functioning affects the mental health of individuals with rheumatoid arthritis. Structural equation modeling techniques were used to assess the relative contributions of age, education, intellectual functioning, self-efficacy, and pain to mental health. It was hypothesized that individuals with rheumatoid arthritis who had higher intellectual functioning and higher self-efficacy would report better mental health than those with lower intellectual functioning and self-efficacy. One hundred twenty-one adults aged 34 to 84 with rheumatoid arthritis completed a battery of cognitive tasks, and multiple measures of self-efficacy, pain, and mental health, twice in 1 month. The data provided a good fit to the hypothesized model. Intellectual functioning was directly related to mental health and, also, indirectly related to mental health through self-efficacy and pain. Older individuals who performed poorly on cognitive tasks reported less self-efficacy, more pain, and poorer mental health than those individuals who performed well on cognitive tasks.
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Zwahr MD, Park DC, Shifren K. Judgments about estrogen replacement therapy: the role of age, cognitive abilities, and beliefs. Psychol Aging 1999. [PMID: 10403707 DOI: 10.1037//0882-7974.14.2.179] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This study investigated age, cognitive abilities, health beliefs, and other factors in women's judgments about effective treatments for menopause. Women (N = 102) ranging in age from 20 to 79 read a vignette about a woman facing a decision about Estrogen Replacement Therapy (ERT) and then made judgments about what should be done. Participants also completed a battery of questions pertaining to ERT and cognitive abilities. Path-analytic techniques were used to determine the role of specific cognitive abilities and the representation of menopause and its treatment in making judgments about ERT treatments. Cognitive abilities had direct effects on treatment decisions. Education affected the number of perceived options for treatment. Age and education indirectly affected treatment decisions, operating through cognitive abilities. Factors related to the mental representation of menopause had no direct effects and few indirect effects on treatment decisions. Potential mechanisms that can help older adults compensate for declines in cognitive abilities in medical decisions are discussed.
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Kim JH, Park DC, Kim JW, Choi YK, Lew YO, Kim DH, Jung JK, Lim YA, Namkoong SE. Antitumor effect of GnRH agonist in epithelial ovarian cancer. Gynecol Oncol 1999; 74:170-80. [PMID: 10419728 DOI: 10.1006/gyno.1999.5413] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The effects of the gonadotropin releasing hormone (GnRH) agonist (D-Trp(6)) were examined in two human ovarian cancer cell lines and in severe combined immune deficiency (SCID) mice to evaluate its potential as a cytocidal, cytostatic, or differentiating antitumor agent. METHODS We treated the human ovarian cancer cell lines OVCAR-3 and SKOV-3 for 5 or 7 days and sex-matched SCID mice with GnRH agonist for 29 days. The antitumor effect of GnRH agonist were studied in various aspects. To confirm the antiproliferative effect, we used 3-(4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide colorimetric assay, in vitro, and a serial measurement of tumor growth in vivo. The disturbances of progression in the cell cycle and the changes of cyclin-dependent kinase 1 following treatment with GnRH agonist were evaluated with flow cytometric analysis in vitro. The induction of apoptosis following treatment with GnRH agonist was studied using in situ terminal deoxyribonucleotidyl transferase (Tdt) and further quantitated with ELISA in vitro. The presence of telomerase activity following treatment with GnRH agonist was measured by PCR-based telomeric repeat amplification protocol and ELISA detection in cell lines and xenografts in vitro and in vivo. RESULTS Continuous exposure of cell lines and xenografts to GnRH agonist resulted in growth inhibition of cancer cells in a dose- and time-dependent manner. In cultured cells, the GnRH agonist blocked cell cycle progression in G0/G1 phase and thus reduced the number of cells in S and G2/M phases. The phenomenon of apoptosis was documented in cultured cells treated with GnRH agonist by in situ Tdt assay. The frequency of apoptotic cells in the in situ Tdt assay was 5-6% compared with control, 4-5%. Apoptosis quantified by ELISA revealed a high incidence in cultured cells treated with GnRH agonist. The activities of telomerase in cell lines and xenografts were not decreased by GnRH agonist. There were not any significant changes of expression of CA-125 by flow cytometry and of the cellular morphology observed with light microscopy. CONCLUSIONS Our results indicate that the antiproliferative effect of GnRH agonist in epithelial ovarian cancer cells may be mainly attributed to cytostatic activities resulting in blocking of cell cycle progression in the G0/G1 phase and minimally related to the induction of apoptosis.
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Abstract
Memory for news stories was studied in 48 young and 48 old adults (20-40 and 60-80 years of age, respectively). Three stories selected from actual news programs were presented in print, audio, and TV formats for study. Young adults recalled a higher proportion of news content than old adults and performed better on source recognition tests. Presentation of the information in a TV format led to better performance than in an audio format for both young and old adults. Hierarchical regression analysis revealed that approximately 86% of the age-related variance in news recall was mediated by measures of sensory acuity and processing speed, and commonality analysis revealed that 75% of the age-related variance was mediated jointly by acuity and speed. Findings support common-cause and generalized slowing views of memory impairment in old age.
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Kim JW, Lee YS, Kim BK, Park DC, Lee JM, Kim IK, Namkoong SE. Cell cycle arrest in endometrial carcinoma cells exposed to gonadotropin-releasing hormone analog. Gynecol Oncol 1999; 73:368-71. [PMID: 10366462 DOI: 10.1006/gyno.1999.5398] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Gonadotropin-releasing hormone (GnRH) has been shown to have an inhibitory effect on the growth of several hormone-dependent human tumors. We have treated a human endometrial cancer cell line which expresses GnRH receptor with GnRH analog, D-Trp6-LHRH, in order to study whether there are differences in cell cycle kinetic response. Flow cytometric analysis revealed that cultured carcinoma cells showed a cell cycle arrest at the G1-S transition after treatment with 10 microM D-Trp6-LHRH for 36 h. Western blot analysis showed that the level of p16 protein was obvious following 24 h of D-Trp6-LHRH treatment. These results suggest that the mechanism by which GnRH inhibits the growth of endometrial carcinoma cells may include effects on cell cycle arrest.
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Zwahr MD, Park DC, Shifren K. Judgments about estrogen replacement therapy: the role of age, cognitive abilities, and beliefs. Psychol Aging 1999; 14:179-91. [PMID: 10403707 DOI: 10.1037/0882-7974.14.2.179] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This study investigated age, cognitive abilities, health beliefs, and other factors in women's judgments about effective treatments for menopause. Women (N = 102) ranging in age from 20 to 79 read a vignette about a woman facing a decision about Estrogen Replacement Therapy (ERT) and then made judgments about what should be done. Participants also completed a battery of questions pertaining to ERT and cognitive abilities. Path-analytic techniques were used to determine the role of specific cognitive abilities and the representation of menopause and its treatment in making judgments about ERT treatments. Cognitive abilities had direct effects on treatment decisions. Education affected the number of perceived options for treatment. Age and education indirectly affected treatment decisions, operating through cognitive abilities. Factors related to the mental representation of menopause had no direct effects and few indirect effects on treatment decisions. Potential mechanisms that can help older adults compensate for declines in cognitive abilities in medical decisions are discussed.
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Abstract
There is evidence that East Asians are biased to process information in a holistic, contextual fashion, whereas Western Europeans process information in an analytic, feature-based style. We argue that these cultural differences in information-processing styles are so pervasive that they affect cognitive function at the most basic levels, including the mechanics of cognition. However, as individual age, it is not always the case that culture effects on cognitive processes magnify, despite many additional years of exposure to the culture. Neurobiological decline in cognitive function that occurs with age is a cognitive universal and can limit the strategies used in late adulthood, resulting in more similarity in cognitive function in late adulthood across cultures than is observed in young adulthood. We present a theoretical framework for understanding the impact of aging on cognitive function cross-culturally. The importance of developing culture-invariant measures of processing resources is emphasized and methodological issues associated with the cross-cultural study of aging are addressed.
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Abstract
Memory for news stories was studied in 48 young and 48 old adults (20-40 and 60-80 years of age, respectively). Three stories selected from actual news programs were presented in print, audio, and TV formats for study. Young adults recalled a higher proportion of news content than old adults and performed better on source recognition tests. Presentation of the information in a TV format led to better performance than in an audio format for both young and old adults. Hierarchical regression analysis revealed that approximately 86% of the age-related variance in news recall was mediated by measures of sensory acuity and processing speed, and commonality analysis revealed that 75% of the age-related variance was mediated jointly by acuity and speed. Findings support common-cause and generalized slowing views of memory impairment in old age.
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Park DC, Sohn YH, Lee PH. Neurologic deficits with isolated cortical venous congestion. Neurology 1999; 52:671-2. [PMID: 10025818 DOI: 10.1212/wnl.52.3.671] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Park DC, Hertzog C, Leventhal H, Morrell RW, Leventhal E, Birchmore D, Martin M, Bennett J. Medication adherence in rheumatoid arthritis patients: older is wiser. J Am Geriatr Soc 1999; 47:172-83. [PMID: 9988288 DOI: 10.1111/j.1532-5415.1999.tb04575.x] [Citation(s) in RCA: 181] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To create a profile of individuals nonadherent to their medications in an age-stratified sample (ages 34-84) of community-dwelling rheumatoid arthritis patients. The relative contributions of age, cognitive function, disability, emotional state, lifestyle, and beliefs about illness to nonadherence were assessed. DESIGN A direct observation approach was used in conjunction with structural equation modeling. All participants were administered a preliminary assessment battery. Medications were then transferred to vials with microelectronic caps that recorded medication events for all medications for the next 4 weeks. PARTICIPANTS AND SETTING A volunteer sample of 121 community-dwelling rheumatoid arthritis (RA) patients were recruited from newspaper ads, posters, and via informal physician contact from private rheumatology practices in Atlanta and Athens, Georgia. Written verification of the RA diagnosis and a disease severity rating were obtained from personal physicians before patients were enrolled in the study. Patients were tested in a private physician's office, and their medication adherence was monitored electronically for a month in their every-day work and home settings. MEASUREMENTS AND RESULTS Structural equation modeling techniques were used to develop a model of adherence behavior. Cognitive and psychosocial measures were used to construct latent variables to predict adherence errors. The model of medication adherence explained 39% of the variance in adherence errors. The model demonstrated that older adults made the fewest adherence errors, and middle-aged adults made the most. A busy lifestyle, age, and cognitive deficits predicted nonadherence, whereas coping with arthritis-related moods predicted adherence. Illness severity, medication load, and physical function did not predict adherence errors. Omission of medication accounted for nearly all errors. CONCLUSION Despite strong evidence for normal, age-related cognitive decline in this sample, older adults had sufficient cognitive function to manage medications. A busy lifestyle and middle age were more determinant of who was at risk of nonadherence than beliefs about medication or illness. Thus, practicing physicians should not assume that older adults have insufficient cognitive resources to manage medications and that they will be the most likely to make adherence errors. Very busy middle-aged adults seem to be at the greatest risk of managing medications improperly.
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Kim JH, Park DC, Bae SN, Namkoong SE, Kim SJ. Subsequent reproductive experience after treatment for gestational trophoblastic disease. Gynecol Oncol 1998; 71:108-12. [PMID: 9784329 DOI: 10.1006/gyno.1998.5167] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE The purpose of this study was to evaluate reproductive performance of patients with gestational trophoblastic disease (GTD) after completion of treatment and follow-up periods. PATIENTS AND METHODS Subjects comprised 115 patients who became pregnant after having been judged completely cured after a follow-up period of at least 1 year. There were 77 hydatidiform-mole patients who had a natural cure and 38 gestational trophoblastic tumor patients who were cured after chemotherapy. We studied these patients with respect to parameters concerning pregnancy outcome. RESULTS Average age at first pregnancy was 28.0 and average number of past deliveries was 1.3. After a 1-year contraception period, the average time to the next pregnancy was 0.8 year, with 59 of 115 (51.3%) women becoming pregnant within 1 year after pregnancy was permitted and 98 women (85.2%) conceiving within 3 years. Results of the pregnancies after cure of GTD did not deviate from normal ranges in separated analyses of complete mole (CM), partial mole (PM), and gestational trophoblastic tumor. Rate of repeat mole was found to be high, occurring in 5 of 115 (4.3%) cases. Rates of antepartum and postpartum complications did not deviate from normal ranges, and there was nothing peculiar about the neonatal sex and weight. CONCLUSION GTD and chemotherapy rarely affect later pregnancies; however, the rate of repeat mole is relatively high.
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Smith AD, Park DC, Earles JL, Shaw RJ, Whiting WL. Age differences in context integration in memory. Psychol Aging 1998. [PMID: 9533187 DOI: 10.1037//0882-7974.13.1.21] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This research examined the role of contextual integration in memories of younger and older adults. In 2 experiments, recall of a target picture to a context picture cue was better when sentences were generated that integrated the picture pair and when the picture pairs were already related to each other. Age differences were smallest when sentences were generated for semantically related pairs. Older adults generated the same type sentences as younger adults, although they generated fewer integrations for unrelated pairs. In a 3rd experiment, younger adults could not differentiate between younger- and older-generated sentences from Experiment 1, and the sentences did not differentially affect recall performance. The results are discussed in terms of age differences in self-initiated processing when using context.
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Park JS, Park DC, Kim CJ, Ahn HK, Um SJ, Park SN, Kim SJ, Namkoong SE. HPV-16-related proteins as the serologic markers in cervical neoplasia. Gynecol Oncol 1998; 69:47-55. [PMID: 9570998 DOI: 10.1006/gyno.1998.4963] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Recently, a variety of HPV-related proteins have been synthesized and their utility as diagnostic and prognostic markers in cervical cancers needs to be assessed. The ability to generate preparative amounts of HPV-16 L1/L2 VLPs and E6, E7 proteins may have implications for the development of a serologic assay to detect anti-HPV-16 virion immune responses. The purpose of the study is to improve the way of proper management of the cervical cancer by investigating the utility of the recently developed HPV-16 L1/L2 VLPs, HPV-16 E6, E7 proteins as the clinical serologic markers through antibody reactions by comparison with those of SCCA and CEA which have been used as tumor markers for cervical cancer. METHODS The serologic responses in Korean women with cervical neoplasia by ELISA using HPV-16 L1/L2 VLPs and radioimmunoprecipitation assay (RIPA) using in vitro translated HPV-16 E6, E7 proteins were investigated. PCR using E6 type-specific primers for HPV-16/18 was used to determine the presence and type of HPV infection (normal controls, 15 cases; preinvasive lesions, 28 cases; invasive cervical cancers, 124 cases). RESULTS The sera of 34% (42/124) of cervical cancers were positive for SCCA and the sera of 18% (22/124) of cervical cancers were positive for CEA. The positivity of SCCA was increased with advancing clinical stages, but the antibody levels were not correlated with clinical stage of disease. The sera of 7% (1/15) of normal controls, 39% (11/28) of preinvasive lesions, and 56% (70/124) of patients with cervical cancer were ELISA positive for HPV-16 L1/L2 VLPs (P < 0.05). The sera of 7% (2/28) of preinvasive lesions and 51% (63/124) of cervical cancers were positive for in vitro translated HPV-16 E6 protein (P < 0.05) and the sera of 11% (3/28) of preinvasive lesions and 33% (41/124) of cervical cancers were positive for in vitro translated HPV-16 E7 protein (P < 0.05). The antibody levels to HPV-16 E7 protein were correlated to clinical stage and tumor burden in a significant number of cervical cancers. CONCLUSIONS These data suggest that a considerable number of patients with cervical neoplasia generated positive antibody response to L1/L2 VLPs and in vitro translated E6, E7 proteins of HPV-16. These HPV-16-associated proteins might be disease-specific markers which could be useful in an adjunctive diagnostic assay and a seroepidemiologic study of HPV-related cervical neoplasia. In particular, the monitoring of antibody to HPV-16 E7 protein seems to be valuable in the proper management of cervical cancers for specific tumor markers.
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Abstract
This research examined the role of contextual integration in memories of younger and older adults. In 2 experiments, recall of a target picture to a context picture cue was better when sentences were generated that integrated the picture pair and when the picture pairs were already related to each other. Age differences were smallest when sentences were generated for semantically related pairs. Older adults generated the same type sentences as younger adults, although they generated fewer integrations for unrelated pairs. In a 3rd experiment, younger adults could not differentiate between younger- and older-generated sentences from Experiment 1, and the sentences did not differentially affect recall performance. The results are discussed in terms of age differences in self-initiated processing when using context.
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Earles JL, Connor LT, Smith AD, Park DC. Interrelations of age, self-reported health, speed, and memory. Psychol Aging 1997; 12:675-83. [PMID: 9416635 DOI: 10.1037/0882-7974.12.4.675] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Contributions of self-reported health to adult age differences in perceptual speed and memory were assessed for 301 adults ages 20-90. Participants were asked 4 health status questions, given 3 perceptual speed tests, 2 working memory tests, and 2 memory tests. Self-reported health was found to predict speed better than it predicted memory. Covariance structural equation modeling was used to assess the relations among age, self-reported health, perceptual speed, working memory, and memory. The results support the hypothesis that any effects of self-reported health on age differences in memory are mediated by perceptual speed.
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Morrell RW, Park DC, Kidder DP, Martin M. Adherence to antihypertensive medications across the life span. THE GERONTOLOGIST 1997; 37:609-19. [PMID: 9343911 DOI: 10.1093/geront/37.5.609] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Although treatment for hypertension is readily available, poor control of hypertension is a major health problem frequently manifested in late life. Researchers believe that one of the major causes of uncontrolled hypertension is failure to take medication as directed. In this preliminary study, the medication-taking behaviors of 48 adults diagnosed with hypertension, ranging in age from 35 to 87, were recorded for 2 months with credit card-sized bar-code scanners. The social-cognitive model (Park, 1992) for understanding medication adherence, which proposes that medication adherence is governed by both beliefs and cognitive factors, was used as a basis for this research. Therefore, measures of health behaviors, attitudes about health and medication taking, and cognitive function were recorded, as well as blood pressure readings. The main findings were that (a) the oldest-old and groups of middle-aged adults were the most nonadherent, whereas the young-old were more likely to adhere than the other age groups; (b) high blood pressure readings predicted adherence to antihypertensive medications; and (c) medication beliefs influenced adherence in some situations.
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Park DC, Hertzog C, Kidder DP, Morrell RW, Mayhorn CB. Effect of age on event-based and time-based prospective memory. Psychol Aging 1997. [PMID: 9189992 DOI: 10.1037//0882-7974.12.2.314] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The magnitude of age differences on event- and time-based prospective memory tasks was investigated in 2 experiments. Participants performed a working memory task and were also required to perform either an event- or time-based prospective action. Control participants performed either the working memory task only or the prospective memory task only. Results yielded age differences on both prospective tasks. The age effect was particularly marked on the time-based task. Performance of the event-based prospective task, however, had a higher cost to performance on the concurrent working memory task than the time-based task did, suggesting that event-based responding has a substantial attentional requirement. The older adults also made a significant number of time-monitoring errors when time monitoring was their sole task. This suggests that some time-based prospective memory deficits in older adults are due to a fundamental deficit in time monitoring rather than to prospective memory.
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Park DC, Hertzog C, Kidder DP, Morrell RW, Mayhorn CB. Effect of age on event-based and time-based prospective memory. Psychol Aging 1997; 12:314-27. [PMID: 9189992 DOI: 10.1037/0882-7974.12.2.314] [Citation(s) in RCA: 162] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The magnitude of age differences on event- and time-based prospective memory tasks was investigated in 2 experiments. Participants performed a working memory task and were also required to perform either an event- or time-based prospective action. Control participants performed either the working memory task only or the prospective memory task only. Results yielded age differences on both prospective tasks. The age effect was particularly marked on the time-based task. Performance of the event-based prospective task, however, had a higher cost to performance on the concurrent working memory task than the time-based task did, suggesting that event-based responding has a substantial attentional requirement. The older adults also made a significant number of time-monitoring errors when time monitoring was their sole task. This suggests that some time-based prospective memory deficits in older adults are due to a fundamental deficit in time monitoring rather than to prospective memory.
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Park DC, Smith AD, Lautenschlager G, Earles JL, Frieske D, Zwahr M, Gaines CL. Mediators of long-term memory performance across the life span. Psychol Aging 1997. [PMID: 9000294 DOI: 10.1037//0882-7974.11.4.621] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
An individual-differences approach was used to examine the component processes that predict episodic long-term memory performance. A total of 301 participants ages 20-90 received a 7-hr cognitive battery across 3 days. Key constructs hypothesized to affect long-term memory function were assessed, including multiple measures of working memory and perceptual speed. Latent-construct, structural equation modeling was used to examine the relationship of these measures and age to different types of long-term memory tasks. Speed was a key construct for all 3 types of memory tasks, mediating substantial age-related variance; working memory was a fundamental construct for free and cued recall but not spatial memory. The data suggest that both speed and working memory are fundamental to explaining age-related changes in cognitive aging but that the relative contributions of these constructs vary as a function of the type of memory task.
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Park DC, Smith AD, Lautenschlager G, Earles JL, Frieske D, Zwahr M, Gaines CL. Mediators of long-term memory performance across the life span. Psychol Aging 1996; 11:621-37. [PMID: 9000294 DOI: 10.1037/0882-7974.11.4.621] [Citation(s) in RCA: 354] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
An individual-differences approach was used to examine the component processes that predict episodic long-term memory performance. A total of 301 participants ages 20-90 received a 7-hr cognitive battery across 3 days. Key constructs hypothesized to affect long-term memory function were assessed, including multiple measures of working memory and perceptual speed. Latent-construct, structural equation modeling was used to examine the relationship of these measures and age to different types of long-term memory tasks. Speed was a key construct for all 3 types of memory tasks, mediating substantial age-related variance; working memory was a fundamental construct for free and cued recall but not spatial memory. The data suggest that both speed and working memory are fundamental to explaining age-related changes in cognitive aging but that the relative contributions of these constructs vary as a function of the type of memory task.
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Earles JL, Smith AD, Park DC. Adult age differences in the effects of environmental context on memory performance. Exp Aging Res 1996; 22:267-80. [PMID: 8872081 DOI: 10.1080/03610739608254011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In two experiments, we examined the hypotheses that the memory performance of older adults is more dependent than that of younger adults on environmental context, and that the integration of to-be-remembered items with contextual cues benefits older more than younger adults. When younger and older adults were shown simple line drawings that were not explicitly associated with the external environment, there was no effect on recall of a change in environmental context for either age group. However, when subjects heard sentences that connected the simple drawings with environmental cues, an environmental context effect was observed. Both age groups recalled more in the same than in a different environment, and the magnitude of the facilitation effect of the familiar context was equal for younger and older adults. However, the integration of the to-be-remembered items with the context facilitated recall regardless of the context present at retrieval, and this effect was larger for younger adults, suggesting that the younger adults were better able to use the provided integrations than were the older adults.
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Shen GP, Park DC, Ullrich RC, Novotny CP. Cloning and characterization of a Schizophyllum gene with A beta 6 mating-type activity. Curr Genet 1996; 29:136-42. [PMID: 8821660 DOI: 10.1007/bf02221577] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The A-pathway of development in the basidiomycete fungus Schizophyllum commune may be activated by either of two mating-type loci, A alpha and A beta. A alpha consists of two multiallelic genes, Y and Z. Y contains a putative homeodomain; Z contains a homeodomain-related region. Non-self combinations of Y and Z form heteromultimers which are thought to be transcription factors of developmental genes. To more completely understand A-regulated development it is necessary to address the issue of functional redundancy, i.e., how do two different mating loci, A alpha and A beta, both manage to regulate the same pathway. Here we report the structure of a gene with A beta 6 activity. This gene, denoted A beta V6, encodes a deduced polypeptide of 640 amino-acids with a homeodomain motif. V6 also contains a 20-amino acid sequence that is conserved in A alpha Y1, Y3 and Y4. Except for the homeodomain and the conserved sequence, the deduced V6 polypeptide shows no significant identity to A alpha Y, A alpha Z, or other known proteins. The presence of a homeodomain suggests that V, like Y and Z, may be a regulatory protein for genes in the A-pathway. Thus while A alpha and A beta encode different proteins, the general mechanism by which A alpha and A beta components signal A-regulated development may be similar.
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Yang H, Shen GP, Park DC, Novotny CP, Ullrich RC. The A alpha mating-type transcripts of Schizophyllum commune. Mycology 1995; 19:16-25. [PMID: 7614367 DOI: 10.1006/emyc.1995.1003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
A alpha 1, A alpha 3, and A alpha 4 ds- and ss-DNA probes from the polymorphic A alpha mating-type locus of Schizophyllum commune were used to probe Northern blots of poly(A+) RNA extracted from strains of various A alpha mating types. The purpose of these experiments was to identify, map, and characterize the transcripts produced from the regions of the A alpha locus. The transcripts unique to A alpha mating type map colinear with the open reading frames identified from DNA sequence and are encoded within the fragments which activate the A developmental pathway in transformation. These data confirm the existence and structure of the previously hypothesized Y and Z A alpha mating-type genes. Transcripts from the Y and Z genes are present in vegetative cells of homokaryons and dikaryons and in cells of the fruiting bodies. The presence of the transcripts throughout the life cycle is consistent with the model of Y and Z proteins as "master switches" of A-regulated development.
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Abstract
The Patient Self-Determination Act became effective in December 1991 and mandates that patients be given information about legal rights regarding living wills and durable powers of attorney for health care. We investigated the impact this law has had on hospitals, medical personnel, and patients. We conducted a survey of all hospitals in the state of Georgia, collecting data regarding implementation and knowledge of the law, as well as effects of the law and beliefs about it. The data indicated that hospitals relied primarily on the Georgia Hospital Association for implementation policy, that "minimalist" implementation of the law occurs in most hospitals, and that the biggest perceived problem with the law was the inappropriateness of presenting this information at hospital admission and problems patients had in comprehending the materials presented. Despite these concerns, most respondents did not want the law repealed.
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