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Shih-Jen Tsai

Publications and source records attributed to Shih-Jen Tsai.

At least 91 records · Page 5Linked to original sources
PubMed2003

No association of tumor necrosis factor alpha gene polymorphisms with schizophrenia or response to clozapine.

Tumor necrosis factor alpha (TNF-alpha), a potent immunomodulator and proinflammatory cytokine, has been implicated in schizophrenia pathogenesis and clozapine response. Two studies have established an association between schizophrenia and the TNF-alpha gene -308G/A polymorphism; however, both increased and decreased -308A allele frequency have been reported in two analogous investigations. The present study examined the hypothesis that the TNF-alpha gene -308G/A polymorphism confers susceptibility to schizophrenia in 205 patients with schizophrenia compared with 192 controls. A subgroup of 99 clozapine-treated schizophrenia patients was also tested for the genetic effects of this polymorphism, as evidenced by clinical manifestation, and clozapine-related therapeutic outcome and body-weight change. The results of these investigations suggest that the TNF-alpha gene -308G/A variants do not play a major role in susceptibility to, clinical manifestations for, or clozapine response in, schizophrenia.

Adult↗
PubMed2003

Association study of a brain-derived neurotrophic-factor genetic polymorphism and major depressive disorders, symptomatology, and antidepressant response.

Preclinical studies have shown that brain-derived neurotrophic factor (BDNF) may be involved in both antidepressant action and the pathophysiology of major depressive disorder (MDD). The present study tested the hypothesis that the BDNF-gene Val66Met polymorphism is associated with MDD, its clinical manifestations, and antidepressant response. To elucidate a genetic predisposition of MDD, we studied BDNF-gene Val66Met polymorphism in 152 MDD patients in 255 normal controls. We also examined the association of this polymorphism and fluoxetine therapeutic response in 110 MDD patients who received a 4-week fluoxetine treatment. No significant differences were demonstrated for the genotype or allele frequency of the BDNF polymorphism comparing the MDD and control groups. Further, no significant differences were noted comparing the three-genotype groups for depressive-cluster symptoms. However, a trend (P = 0.086) to improved 4-week-fluoxetine antidepressant response was demonstrated for heterozygous patients in comparison to homozygous analogs. This finding suggests the BDNF polymorphism investigated plays no major role in the pathogenesis of MDD.

Adult↗
PubMed2003

An association study of a brain-derived neurotrophic factor Val66Met polymorphism and clozapine response of schizophrenic patients.

A growing body of evidence suggests the involvement of brain-derived neurotrophic factor (BDNF) in both antipsychotic action and schizophrenia pathogenesis. The present study tested the hypothesis that the BDNF-gene Val66Met polymorphism is associated with schizophrenia and clozapine's therapeutic response. To identify any genetic predisposition to schizophrenia, we studied the BDNF-gene Val66Met polymorphism in 93 schizophrenic patients and 198 normal controls. Statistical analysis was used to test the association between this polymorphism and clozapine response the schizophrenic group. A trend (P=0.055) was demonstrated between genetic predisposition and Val66Met genotypes in 93 schizophrenic patients, especially for those with good response to clozapine (P=0.023). No significant difference in clozapine therapeutic response was demonstrated comparing the three Val66Met-genotype subgroups. Our finding suggests that this BDNF-gene Val66Met polymorphism may be related to schizophrenia pathogenesis in patients responsive to clozapine treatment.

Adult↗
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

Association study of the interleukin-1 beta (C-511T) genetic polymorphism with major depressive disorder, associated symptomatology, and antidepressant response.

Proinflammatory cytokines, including interleukin (IL)-1beta, are suggested to have a role in the pathogenesis of major depressive disorder (MDD) and be related to the therapeutic effects of antidepressants. To elucidate a genetic predisposition of MDD, we studied biallelic polymorphism in the promoter region (position -511) of the IL-1beta gene in 157 patients with MDD and in 112 controls. We also examined the association of this polymorphism and fluoxetine therapeutic response in 119 MDD patients who received a 4-week fluoxetine treatment. No significant difference was found in the genetic polymorphism between MDD patients and controls. However, MDD patients who were homozygous for the -511T allele of the IL-1beta gene had a trend of less severity of depressive symptoms and more favorable fluoxetine therapeutic response than -511C carriers. Further study with a larger sample is needed to clarify the role of the IL-1beta genetic polymorphisms in the symptoms and treatment effects in MDD.

Adolescent↗
PubMed2003

Phantom boarder symptom in dementia.

OBJECTIVE: Phantom boarder symptom (PBS), which has been labelled a misidentification and is commonly observed in cases of Alzheimer's disease, is the perceptual dysfunction where it is imagined that there are people in the home. It may also be encountered in cases of vascular dementia and other variants of this cognitive dysfunction. This study was undertaken to investigate PBS frequency and characteristics for a sample of dementia inpatients, and to determine the strength of the association with other psychotic symptoms. METHODS: The sample population consisted of 240 dementia patients admitted to our geropsychiatric ward. Patients with and without PBS were compared in terms of general characteristics and psychotic symptoms. RESULTS: Of the 240 dementia patients, PBS was identified in 56 (23.3%). There were no significant gender differences between the PBS and non-PBS groups. Means for age and onset-age were higher for the PBS group, and the prevalence of hallucinations and other misidentifications was greater compared to the non-PBS analog. Occurrence of PBS was not significantly associated with delusions or physical aggression. CONCLUSIONS: PBS is a common symptom in dementia of various etiologies. Our association findings suggest that it may be more productive to classify PBS as a type of misidentification, instead of as a delusion.

Age of Onset↗
PubMed2003

Clinical and phenomenological comparisons of delusional and non-delusional major depression in the Chinese elderly.

OBJECTIVE: Distinct clinical entities, with and without delusions, have been reported for depressed patients. This study explores the clinical and phenomenological aspects of delusional and non-delusional major depression in elderly Chinese patients. METHODS: A total of 156 depressed patients (105 males and 51 females) admitted to our geriatric psychiatry ward were investigated. Sociodemographic and clinical characteristics were compared between patients divided into two groups-according to presence or absence of delusions. RESULTS: On admission, higher risk of suicide attempt, higher chance of guilt feelings, and greater daily functional impairment were observed for the deluded group. Further, the score of Hamilton Depression Rating Scale was higher and the score of Mini-Mental State Examination was lower for delusional depressives. CONCLUSION: Our findings were grossly concordant with previous Western reports, and highlight the importance of identifying the delusional subgroup of depressive patients because of the higher risk of suicide attempt.

Activities of Daily Living↗
PubMed2003

Dopamine receptor hetero-oligomerization: a hypothesis for behavioral sensitization to psychostimulants.

Repeated psychostimulant pretreatment can induce behavioral sensitization. Many previous studies have demonstrated that receptors of the dopamine and other neurotransmitter systems are involved in the sensitization process, however, the precise mechanism of this interaction is still unknown. We propose the hypothesis that oligomerization of the dopamine receptors and analogs from other neurotransmitter systems may contribute, at least in part, to psychostimulant-induced behavioral sensitization. Psychostimulant exposure can enhance central dopamine release, which can increase oligomerization of the dopamine receptors with their analogs. Receptor oligomerization can enhance the functional properties of the receptors and affect receptor degradation, which may be related to the behavioral augmentation which characterizes the sensitized state and produces the persistence of behavioral sensitization. The proposed receptor hetero-oligomerization model may provide a new direction in the exploration of the functionally critical sensitization phenomenon.

Amphetamines↗
PubMed2003

Attention-deficit hyperactivity disorder and brain-derived neurotrophic factor: a speculative hypothesis.

Brain-derived neurotrophic factor (BDNF) is important for normal neuronal development. Attention-deficit hyperactivity disorder (ADHD), a childhood-onset neurodevelopmental disorder, is characterized by inattention and hyperactivity. Psychostimulants and antidepressants are the agents commonly used for the treatment of ADHD and were also found to elevate central BDNF. It is proposed here that BDNF may play a role in the therapeutic action and pathogenesis of ADHD. This hypothesis may provide a new direction for the treatment and the pathogenesis of ADHD.

Adolescent↗
PubMed2003

Brain-derived neurotrophic factor: a bridge between major depression and Alzheimer's disease?

Cognitive impairment is common in major depression (MD) patients, with these individuals incurring increased risk for development of Alzheimer's disease (AD). Further, depressive symptoms are common in AD patients. This apparent convergence suggests pathogenic factors common to AD and MD. Since decreased brain-derived neurotrophic factor (BDNF), a member of the neurotrophic factor family, is related to both AD and MD, the author suggests that BDNF could be a bridge between AD and MD, explaining both the depressive symptoms in AD, and, cognitive impairment in MD. Evidence supporting this hypothesis suggests that early antidepressants treatment for aged MD patients may decrease the risk of AD, and agents that increase central BDNF may offer an alternative treatment for MD patients with cognitive impairment and/or for AD sufferers with depressive symptoms.

Alzheimer Disease↗
PubMed2003

The efficacy and safety of olanzapine for the treatment of geriatric psychosis.

Elderly psychiatric patients often present with psychotic symptoms that need antipsychotic treatment. Olanzapine is one of the atypical antipsychotics with efficacy for psychotic symptoms and a safer side-effect profile than typical antipsychotics. This study was conducted to assess the efficacy and safety of olanzapine for treatment of geriatric psychosis. The sample population comprised 94 acute-ward patients who were 65 years of age or older. Clinical assessment was conducted at baseline and also at 4 weeks after commencement of olanzapine treatment, with use of the Brief Psychiatric Rating Scale (BPRS) and Clinical Global Impression Improvement (CGI-I) instruments. A 4-week therapeutic evaluation was completed for 80 patients, 73 of whom (91.3%) experienced mild to substantial improvement as determined from the CGI-I. A mean 52.6% reduction from baseline was also determined from the BPRS. The mean daily dosage of olanzapine in the fourth week was 10.1 +/- 5.3 mg/d (range, 2.5-20.0). Higher olanzapine dosages were administered for patients with functional psychoses than for an analogous group with organic mental disorders. Adverse effects were monitored for all 94 patients, the most common of which were somnolence (18.1%), dizziness (18.1%), and weakness of legs or bradykinesia (16.0%). Body weight and fasting triglyceride and sugar levels were significantly elevated after olanzapine treatment (2.2, 39.9, and 8.9% from baseline, respectively). It seems reasonable to suggest that olanzapine is efficacious for geriatric patients with psychosis and that the dosage should be diagnosis-dependent.

Acute Disease↗
PubMed2003

Association study of oestrogen receptor alpha gene polymorphism and suicidal behaviours in major depressive disorder.

OBJECTIVE: Gender comparison in epidemiological studies has consistently demonstrated a greater prevalence for major depressive disorders (MDD) in females. Several lines of evidence have implicated oestrogen pathways in this gender difference. Furthermore, there is evidence that attempted suicides are more frequent in women. A population-based association study was used to test the hypothesis that the genetic variants ( II and I polymorphisms) of the oestrogen receptor alpha gene (ER-alpha) confer susceptibility to MDD. METHODS: The ER-alpha was genotyped for 154 patients with MDD and 226 controls in a Chinese population. RESULTS: Statistical analysis showed a significant difference in the II genotype and allele frequencies between the female MDD patients and the female controls ( P=0.010 and P=0.004, respectively). However, no significant differences in ER-alpha genotype or allele frequencies were found between male MDD patients and male controls. Furthermore, the ER-alpha genotypes were not associated with suicide-attempt history for MDD cases. CONCLUSIONS: Our results suggest that the ER-alpha may play a role in the susceptibility of MDD in females.

Base Sequence↗
PubMed2003

Association analysis for dopamine D3 receptor, dopamine D4 receptor and dopamine transporter genetic polymorphisms and P300 event-related potentials for normal young females.

OBJECTIVE: It has been demonstrated that the P300 components, a positive event-related potential, are heritable and are influenced by dopaminergic activity. We tested the genetic effects of the dopaminergic system in P300 components by association study. METHODS: In a sample population consisting of 120 normal young Han-Chinese females, we explored the association between the P300 components, and, the genetic polymorphisms including the dopamine D3 receptor (serine-to-glycine polymorphism in exon I), the dopamine D4 receptor (variable number tandem repeat polymorphism in exon III), and the dopamine transporter (variable number tandem repeat polymorphism in promoter region). RESULTS: No associations were demonstrated between the polymorphisms of these three genes and the P300 components. CONCLUSIONS: Our negative findings suggest that these genetic polymorphisms do not play a major role in the modulation of P300 event-related potentials.

Adult↗
PubMed2003

Association analysis for neuronal nitric oxide synthase gene polymorphism with major depression and fluoxetine response.

Nitric oxide (NO) is produced from its precursor L-arginine by the enzyme NO synthase (NOS), which includes at least three distinct isoforms - neuronal (nNOS), endothelial, and inducible NOS. Recent studies have implicated NOS in the mechanism that underlies the therapeutic efficacy of antidepressant medication. In addition, major depressive disorder (MDD) patients were found to have significantly higher plasma nitrate concentrations than normal subjects, an index of NO production, in comparison to normal subjects. In a population-based association study, we tested the hypothesis that the nNOS C276T polymorphism confers susceptibility to MDD. We also examined the association between this polymorphism and therapeutic fluoxetine response in 114 MDD patients who underwent a 4-week fluoxetine treatment. The results demonstrate that the nNOS variants are found at similar frequencies in MDD patients and healthy control subjects. Further, we did not discover any genetic variants that influenced the fluoxetine response in MDD patients treated with fluoxetine. Our findings suggest that this nNOS C276T polymorphism does not play a major role in the susceptibility to, or fluoxetine response in, MDD. However, the association between other NOS variants and MDD or antidepressant response, including sexual dysfunction, may warrant further investigation.

Adult↗
PubMed2003

Association study of serotonin transporter gene VNTR polymorphism and mood disorders, onset age and suicide attempts in a Chinese sample.

The human serotonin transporter (5-HTT) gene is an important candidate for the pathogenesis of mood disorders. Associations have been reported between a variable-number tandem-repeat polymorphism in intron 2 of the serotonin transporter gene (5-HTTVNTR) and mood disorders in a number of studies of Western and Chinese populations. However, no such relationships have been determined in other analogous research. To replicate these positive findings in a Chinese population and to determine the association between onset age of bipolar disorder and 5-HTTVNTR, we investigated the prevalence of this polymorphism in an independent Chinese population (83 bipolar disorder patients, 77 major depressive disorder patients and 169 controls), demonstrating no significant association between the 5-HTTVNTR polymorphism and mood disorders or age at onset. Further, no association was demonstrated between this polymorphism and suicidal history in mood disorder patients. These negative findings suggest that 5-HTTVNTR does not play a major role in the pathogenesis of mood disorder in Chinese populations.

Adult↗
PubMed2003

Allelic variants of the tryptophan hydroxylase (A218C) and serotonin 1B receptor (A-161T) and personality traits.

Human personality traits have a considerable hereditary component, and central serotonergic activity is implicated in the personality factors of the Tridimensional Personality Questionnaire (TPQ). Our population-based association study tested the hypothesis that the tryptophan hydroxylase (TPH) A218C and serotonin 1B receptor (HTR1B) A-161T polymorphisms were associated with TPQ personality trait scores in a sample population of 209 young healthy Chinese. No significant differences were demonstrated comparing scores of subjects bearing different TPH or HTR1B genotypes; however, a trend for difference in the novelty seeking score comparing TPH genotype groups was determined for the male population. Our negative findings suggest that the TPH A218C and HTR1B polymorphisms do not play major roles in the determination of TPQ personality traits.

Adult↗