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Hsiu-Chih Liu

Publications and source records attributed to Hsiu-Chih Liu.

At least 19 recordsLinked to original sources
PubMed2004

Association analysis for the muscarinic M1 receptor genetic polymorphisms and Alzheimer's disease.

In the ongoing search to reveal the pathophysiology of Alzheimer's disease (AD), the cholinergic system is important due to its role in cognitive function and its significance with respect to the results of postmortem pathology and animal model studies. For this investigation, we tested the hypothesis that the allelic variant (C267A) of the cholinergic receptor muscarinic 1 (CHRM1) confers susceptibility to AD or is related to its age of onset, in a sample population of 232 AD patients and 169 normal controls. The distribution of the CHRM1 genotypes (p = 0.919) and alleles (p = 0.327) did not differ significantly comparing AD patients and controls, even after stratification according to apolipoprotein E genotype. The onset age was not significantly different comparing the CHRM1 genotype groups. Our negative findings suggest that it is unlikely that the CHRM1 C267A polymorphism plays a substantial role in conferring susceptibility to AD. We propose that other genetic variations of CHRM1, relating either to AD or to the therapeutic response for AD, may need further investigation.

Aged↗
PubMed2004

Polymorphisms of estrogen-metabolizing genes and risk of hepatocellular carcinoma in Taiwan females.

Estrogen has been related to the development of hepatocellular carcinoma (HCC). In this molecular epidemiological study, we used logistic regression to compare the genotype frequencies of estrogen-metabolizing genes that are involved in estrogen biogenesis (CYP17), hydroxylation (CYP1A1) and inactivation of the reactive metabolites (catechol-O-methyltransferase, COMT) in HCC patients and control subjects, and determined their relationship with the risk of female HCC. The heterozygous or homozygous variants of high activity CYP17 (A2), high inducibility CYP1A1(m1), and low activity COMT (L) alleles were considered as high-risk genotypes. We found that the risk of HCC was elevated in women harboring either heterozygous or homozygous variants of the CYP1A1 gene and the respective OR (and 95% confidence interval) were 6.61 (1.35, 32.43) and 12.00 (1.73, 83.46). Moreover, we found that the risk of HCC was increased in the female subjects harboring higher numbers of high-risk genotypes, but not in male subjects. The OR for female HCC associated with two putative high-risk genotypes was 12.63 (1.50, 106.37), and the OR for three putative high-risk genotypes was 16.67 (1.82, 152.77). These findings strongly suggest that estrogen play a critical role in female hepatocarcinogenesis.

Carcinoma, Hepatocellular↗
PubMed2004

Improving the screening power of the cognitive abilities screening instrument, Chinese version.

The purpose of this study was to find means to increase the power of the Cognitive Abilities Screening Instrument, Chinese version (CASI C-2.0) in the screening of dementia. In assessing the performance of the CASI in dementia screening, it is a common practice to determine a cutoff score for the total CASI score and report the respective sensitivity and specificity. In this paper, we showed that an alternative scoring system, i.e., a weighted sum of the scores from the 9 domains in the CASI C-2.0, may improve its effectiveness in screening. In particular, short-term memory and orientation appeared to be the 2 most relevant domains and their combined score was shown to be more effective than the total score in screening dementia. We also showed that such a scoring system could be kept the same across examinees with different demographic backgrounds. With the weighted scoring system of the 9 domains for patients from the targeted population, we hope to make the CASI a clinically more powerful tool in screening dementia.

Adult↗
PubMed2004

Longitudinal cerebral perfusion decrease in mild alzheimer's disease revealed by SPECT with statistical parametric mapping method.

Fifteen patients with mild Alzheimer's disease received baseline and follow-up technetium-99m hexamethylpropylene amine oxime SPECT examinations paired with neuropsychological assessments, including the Cognitive Ability Screening Instruments (CASI). The differences between baseline and follow-up SPECT images were analyzed by the voxel-based paired t test of the statistical parametric mapping technique. A simple regression analysis was also conducted to analyze the correlation between CASI sub-scores and both sets of SPECT images. In comparison with baseline images, cerebral perfusion at follow-up was significantly reduced in the left superior and middle temporal gyri, right middle and inferior temporal gyri, and right fusiform gyrus. A significant correlation was demonstrated between the list-generating fluency CASI sub-score and perfusion of the left fusiform gyrus. The visual construction sub-score was significantly correlated with perfusion of the right superior and medial frontal gyri.

Aged↗
PubMed2004

Getting lost: directed attention and executive functions in early Alzheimer's disease patients.

This study explores the link between directed attention (DA) and getting lost behavior (GLB) in early Alzheimer's disease (AD) using a cross-sectional design with 3 groups. Based on their dementia levels, 116 community-dwelling participants were recruited from a teaching hospital in Taiwan and classified as the non-demented control, questionably demented, and mild AD groups. Statistical analyses include Pearson correlations, one-way ANOVA, and multiple regressions. Attentional impairments, consisting of distractibility, impulsivity, and executive function problems, significantly predict GLB in familiar and unfamiliar environments. Irritability and executive function problems are associated with mental difficulties in choosing a turn, whereas the use of way-finding strategies reduces GLB. Future interventions may include: (a) mental hygiene of aging; (b) programs targeted at improving attentional function and effective way-finding, and (c) inclusion of DA tests in a routine clinical neuropsychological examination for early detection and accurate diagnosis of dementia.

Aged↗
PubMed2004

Weight loss, nutritional status and physical activity in patients with Alzheimer's disease. A controlled study.

The etiology of weight loss in Alzheimer's disease (AD) patients is still uncertain. This study was designed to investigate the possible factors that might contribute to weight change of AD patients. From July 1999 to June 2001, we recruited 51 AD patients and 27 non-demented controls. Demographic data, neuropsychological tests, Geriatric Depression Scale-Short Form, eating behavior questionnaire, dietary and physical activity diaries, anthropometric and laboratory measures of nutritional status were assessed. More than half of our AD patients developed body weight loss, and overall, the AD patients were significantly thinner than the non-demented subjects. Anthropometric and laboratory measures suggested a poorer nutritional status in the AD patients. The AD patients had fewer daily physical activities. More AD patients had the problem of poor appetite. However, daily calorie intake was not significantly different between the two groups. The AD patients, especially those who presented with body weight loss, even consumed more calories per body weight kilogram (kg) per day. In the food composition analysis, AD patients took more carbohydrate than controls. Multivariate regression analysis showed the existence of AD and poor appetite were the main risk factors of weight loss. We suggest that the pathophysiological process in AD gives rise to the changes of appetite and metabolic state in AD patients, and that these changes contribute to the weight loss.

Aged↗
PubMed2004

Association analysis of brain-derived neurotrophic factor Val66Met polymorphisms with Alzheimer's disease and age of onset.

Because of a decrease in central brain-derived neurotrophic factor (BDNF) levels in Alzheimer's disease (AD) and the important role of BDNF in neuronal survival, BDNF may represent a candidate gene conferring susceptibility to AD. Recently, a functional BDNF Val66Met polymorphism has been associated with AD in an Italian population. In the present study, we investigated a possible role of this BDNF polymorphism in the susceptibility of AD or AD onset in a Chinese population. Comparing AD patients and controls, the distribution of the BDNF genotypes and alleles did not differ significantly. The onset age was not significantly different comparing the three BDNF genotype groups. Our negative findings suggest that it is unlikely that the BDNF Val66Met polymorphism plays a major role in the pathogenesis of AD in the Chinese population and do not support previous findings that homozygosity for the 66Val allele confers an increased risk for AD. Further studies with genetic variations in BDNF relating either to AD-associated depression or to the AD treatment response are suggested.

Age of Onset↗
PubMed2004

Isolated oculomotor nerve palsy due to head injury.

Traumatic isolated oculomotor nerve palsy with negative imaging studies is extremely rare. We reported such a case who after head injury had normal brain computerized tomography (CT), magnetic resonance imaging (MRI), and angiography. The absence of other neurological signs and normal brain MRI indicated the lesion was most likely within the subarachnoid space, as the other important structures near the third nerve, such as the brainstem, cavernous sinus and orbit, were undamaged. The prognosis of traumatic oculomotor palsy is usually poor. Generally speaking, patients experience more rapid and complete recovery of ptosis than of extraocular movements, while pupillary size and light reflex show the least degree of recovery. Further case collections with modern imaging studies are needed to clarify the mechanisms and clinical characteristics associated with this phenomenon.

Brain↗
PubMed2003

Brain-derived neurotrophic factor (BDNF) Val66Met polymorphisms in Parkinson's disease and age of onset.

Given the implications with respect to neuronal survival and the decreased level of the protein in the striatal region in Parkinson's disease (PD), brain-derived neurotrophic factor (BDNF) may be a candidate gene conferring susceptibility to PD. In a recent study of a Japanese population, a functional BDNF Val66Met polymorphism was associated with PD, however, an analogous investigation of a western population did not replicate this finding. In the present study of a Chinese sample, we have investigated the associations between the BDNF polymorphism and susceptibility to PD and PD onset age. The distribution of the BDNF genotypes and alleles did not differ significantly comparing PD patients and controls. Further, the onset age was not significantly different comparing the three BDNF genotype groups. Thus, our negative findings suggest that it is unlikely that the BDNF Val66Met polymorphism plays a major role in the pathogenesis of PD in the Chinese population. Other BDNF genetic variants, and the association of these variants with PD symptomatology or treatment response, may merit further investigation.

Age of Onset↗
PubMed2003

Lack of association between the interleukin-1alpha gene C(-889)T polymorphism and Alzheimer's disease in a Chinese population.

Interleukin 1A (IL-1A), a potent proinflammatory cytokine, has been implicated in the pathogenesis of Alzheimer's disease (AD). Several recent studies have shown that a polymorphism in the IL-1A locus -889 was associated with AD risk and onset age, however, other studies were not able to replicate these findings. In this investigation, the IL-1A C(-889)T polymorphism has been analyzed for a Chinese population of 234 AD patients and 170 controls. There were no significance differences in IL-1A genotype or allele frequencies comparing the AD cases and controls, even after stratification for age of onset and adjustment for apolipoprotein E genotype. The results reveal that it is not likely that the IL-1A C(-889)T polymorphism is involved in AD pathogenesis in the Chinese population. Further studies of the associations between other IL-1A genetic polymorphisms and AD are needed to fully elaborate the involvement of this gene in AD.

Aged↗
PubMed2003

Generalized Kohonen's competitive learning algorithms for ophthalmological MR image segmentation.

Kohonen's self-organizing map is a two-layer feedforward competitive learning network. It has been used as a competitive learning clustering algorithm. In this paper, we generalize Kohonen's competitive learning (KCL) algorithm with fuzzy and fuzzy-soft types called fuzzy KCL (FKCL) and fuzzy-soft KCL (FSKCL). These generalized KCL algorithms fuse the competitive learning with soft competition and fuzzy c-means (FCM) membership functions. We then apply these generalized KCLs to MRI and MRA ophthalmological segmentations. These KCL-based MRI segmentation techniques are useful in reducing medical image noise effects using a learning mechanism. They may be particularly helpful in clinical diagnosis. Two real cases with MR image data recommended by an ophthalmologist are examined. First case is a patient with Retinoblastoma in her left eye, an inborn malignant neoplasm of the retina frequently metastasis beyond the lacrimal cribrosa. The second case is a patient with complete left side oculomotor palsy immediately after a motor vehicle accident. Her brain MRI with MRA, skull routine, orbital CT, and cerebral angiography did not reveal brainstem lesions, skull fractures, or vascular anomalies. These generalized KCL algorithms were used in segmenting the ophthalmological MRIs. KCL, FKCL and FSKCL comparisons are made. Overall, the FSKCL algorithm is recommended for use in MR image segmentation as an aid to small lesion diagnosis.

Algorithms↗
PubMed2003

The three-item clock-drawing test: a simplified screening test for Alzheimer's disease.

The Clock-Drawing Test (CDT) has been used to screen for Alzheimer's disease (AD) as a supplement to cognitive tests that focus on memory impairment. We examined a comprehensive scoring system of the CDT in screening of AD in a Chinese population and derived a simplified scoring system. All 403 (144 AD and 259 nondemented) subjects were administered the CDT, including both the drawing part (CDT-D) and the copying part (CDT-C). The Cognitive Abilities Screening Instrument and the Clinical Dementia Rating were also administered. Stepwise discriminant analysis was used to develop a simplified CDT scoring system. The optimal CDT cutoff scores (CDT-D: 10/11; CDT-C: 12/13) show intermediate sensitivity (CDT-D: 66.7%; CDT-C: 51.4%) and specificity (CDT-D: 74.5%; CDT-C: 74.1%). The simplified 3-item CDT scoring system, with a cutoff score of 2/3, has a sensitivity of 72.9% and a specificity of 65.6%; it can be used as a quick test for AD screening.

Adult↗
PubMed2003

Statistical parametric mapping of brain SPECT perfusion abnormalities in patients with Alzheimer's disease.

Brain perfusion in 20 patients with mild Alzheimer's disease (AD), 20 patients with moderate AD and 20 control subjects (matched for age, gender and education) were assessed by single photon emission computed tomography (SPECT) using technetium-99m hexamethylpropylene amine oxime ((99m)Tc-HMPAO). SPECT images were transformed to a standard size and shape for group comparisons by the voxel-based t test of the statistical parametric mapping techniques. Cerebral hypoperfusion in the left lower parietal area was found in mild AD patients. In moderate AD patients, significant cerebral hypoperfusion was located in bilateral posterior parietotemporal cortices, contiguous anterior occipital lobes, posterior cingulate gyri and, to a lesser extent, in frontal areas.

Aged↗
PubMed2003

Selective hypoperfusion of anterior cingulate gyrus in depressed AD patients: a brain SPECT finding by statistical parametric mapping.

This study tests the hypothesis that depression in patients with Alzheimer's disease (AD) is due to a specific pathogenesis rather than a reactive phenomenon. Forty-three AD patients received a psychiatrist's interview, neuropsychological assessments, and a 99mTc-hexamethyl propyleneamine oxime single photon emission computed tomography (HMPAO-SPECT). Analysis by statistical parametric mapping (SPM) showed that the depressed group had selective hypoperfusion in the bilateral anterior and posterior cingulate gyri and precuneus. Using the Hamilton Depression Rating Scale as a parameter, an inverse correlation was found between cerebral perfusion and the severity of depression. The right anterior cingulate gyrus demonstrated a most significant reduction in perfusion. These locations are akin to the imaging findings in patients with primary depression, indicating a specific pathogenesis for depression in AD.

Aged↗
PubMed2003

Smoking and cognitive performance in the community elderly: a longitudinal study.

This prospective study investigated the association between smoking and cognitive performance in a community of nondemented elderly subjects aged 65 or older. All subjects were categorized as current smokers, former smokers, or never smokers. The lifetime cigarette exposure was computed. At baseline, we found the abstainers from smoking had better cognitive performances; however, the differences were not significant after adjusting for age, education, hypertension, diabetes, and vascular events. The lifetime cigarette exposure was not predictive of the cognitive status. At a 3-year follow-up, neither the smoking status nor the lifetime cigarette exposure predicted the declination of cognition.

Aged↗
PubMed2002

Study of the association between Alzheimer's disease and angiotensin-converting enzyme gene polymorphism using DNA from lymphocytes.

Angiotensin-converting enzyme (ACE) may play a role in cognition and memory. A recent study found that a 287-bp insertion/deletion (I/D) polymorphism of the ACE gene is associated with susceptibility to Alzheimer's disease (AD). However, this finding has not been replicated by all studies. These discrepancies may be due to the difference in ethnic background. Therefore, we investigated the possibility of such an association in 173 AD patients and 286 normal controls from a Chinese population. We found that there is an increased frequency of the ACE I allele in AD patients and the odds ratio for bearers of the I allele was 2.88. Our findings further support previous reports of an association between ACE polymorphism and AD. The implication of the ACE I/D polymorphism in the pathogenesis of AD warrants further exploration.

Adult↗