The D614G mutation redirects SARS-CoV-2 spike to lysosomes and suppresses deleterious traits of the furin cleavage site insertion mutation

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) egress occurs by lysosomal exocytosis. We show that the Spike D614G mutation enhances Spike trafficking to lysosomes, drives Spike-mediated reprogramming of lysosomes, and reduces cell surface Spike expression by ~3-fold. D614G is not a human-specific adaptation. Rather, it is an adaptation to the earlier furin cleavage site insertion (FCSI) mutation that occurred at the genesis of SARS-CoV-2. While advantageous to the virus, furin cleavage of spike has deleterious effects on spike structure and function, inhibiting its trafficking to lysosomes and impairing its infectivity by the transmembrane serine protease 2(TMPRSS2)-independent, endolysosomal pathway. D614G restores spike trafficking to lysosomes and enhances the earliest events in SARS-CoV-2 infectivity, while spike mutations that restore SARS-CoV-2's TMPRSS2-independent infectivity restore spike's trafficking to lysosomes. Together, these and other results show that D614G is an intragenic suppressor of deleterious traits linked to the FCSI and lend additional support to the endolysosomal model of SARS-CoV-2 egress and entry.

The D614G Mutation Enhances the Lysosomal Trafficking of SARS-CoV-2 Spike

The spike D614G mutation increases SARS-CoV-2 infectivity, viral load, and transmission but the molecular mechanism underlying these effects remains unclear. We report here that spike is trafficked to lysosomes and that the D614G mutation enhances the lysosomal sorting of spike and the lysosomal accumulation of spike-positive punctae in SARS-CoV-2-infected cells. Spike trafficking to lysosomes is an endocytosis-independent, V-ATPase-dependent process, and spike-containing lysosomes drive lysosome clustering but display poor lysotracker labeling and reduced uptake of endocytosed materials. These results are consistent with a lysosomal pathway of coronavirus biogenesis and raise the possibility that a common mechanism may underly the D614G mutation’s effects on spike protein trafficking in infected cells and the accelerated entry of SARS-CoV-2 into uninfected cells.

Efficacy of a Latex Agglutination Test for Rapid Identification of Staphylococcus aureus: Collaborative Study

Fifteen laboratories completed a collaborative study comparing the efficacy of a latex agglutination kit (Aureus Test) with that of AOAC Official Method 987.09 (coagulase test for identification of Staphylococcus aureus). Each laboratory analyzed 240 strains of bacteria, including 160 isolates of S. aureus and 80 isolates of other bacteria. Upon receipt of cultures, collaborators subcultured each isolate on both tryptic soy agar (TSA) and Baird-Parker agar medium (BPA) to determine whether the growth medium has any effect on either method. For cultures grown on TSA, the latex test had sensitivity and specificity rates of 99.2 and 97.1 %, respectively, whereas the coagulase test had respective rates of 98.4 and 92.5%. For cultures able to grow on BPA, the latex test had sensitivity and specificity rates of 99.2 and 96.6%, respectively, while the coagulase test had respective rates of 98.3 and 91.3%. By using the McNemar pairwise comparison test of the 2 methods, the falsepositive and false-negative rates of the latex test were significantly lower (p < 0.01) than those of the coagulase test for strains grown either on TSA or BPA. The latex agglutination test for identification of S. aureus isolated from foods has been adopted by AOAC INTERNATIONAL.

Independent component analysis of functional networks for response inhibition: Inter-subject variation in stop signal reaction time

Cognitive control is a critical executive function. Many studies have combined general linear modeling and the stop signal task (SST) to delineate the component processes of cognitive control. For instance, by contrasting stop success (SS) and stop error (SE) trials in the SST, investigators examined regional responses to stop signal inhibition. In contrast to this parameterized approach, independent component analysis (ICA) elucidates brain networks subserving cognitive control. In our earlier work of 59 adults performing the SST during fMRI, we characterized six independent components (ICs). However, none of these ICs correlated with stop signal performance, raising questions about their behavioral validity. Here, in a larger sample (n = 100), we identified and explored 23 ICs for correlation with the stop signal reaction time (SSRT), a measure of the efficiency of response inhibition. At a corrected threshold (P < 0.0005), a paracentral lobule-midcingulate network and a left inferior parietal-supplementary motor-somatomotor network showed a positive correlation between SE beta weight and SSRT. In contrast, a midline cerebellum-thalamus-pallidum network showed a negative correlation between SE beta weight and SSRT. These findings suggest that motor preparation and execution prolongs the SSRT, likely via an interaction between the go and stop processes as suggested by the race model. Behaviorally, consistent with this hypothesis, the difference in G and SE reaction times is positively correlated with SSRT across subjects. These new results highlight the importance of cognitive motor regions in response inhibition and support the utility of ICA in uncovering functional networks for cognitive control in the SST.

The International SSRI Pharmacogenomics Consortium (ISPC): a genome-wide association study of antidepressant treatment response

Response to treatment with selective serotonin reuptake inhibitors (SSRIs) varies considerably between patients. The International SSRI Pharmacogenomics Consortium (ISPC) was formed with the primary goal of identifying genetic variation that may contribute to response to SSRI treatment of major depressive disorder. A genome-wide association study of 4-week treatment outcomes, measured using the 17-item Hamilton Rating Scale for Depression (HRSD-17), was performed using data from 865 subjects from seven sites. The primary outcomes were percent change in HRSD-17 score and response, defined as at least 50% reduction in HRSD-17. Data from two prior studies, the Pharmacogenomics Research Network Antidepressant Medication Pharmacogenomics Study (PGRN-AMPS) and the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study, were used for replication, and a meta-analysis of the three studies was performed (N=2394). Although many top association signals in the ISPC analysis map to interesting candidate genes, none were significant at the genome-wide level and the associations were not replicated using PGRN-AMPS and STAR*D data. The top association result in the meta-analysis of response represents SNPs 5′ upstream of the neuregulin-1 gene, NRG1 (P = 1.20E - 06). NRG1 is involved in many aspects of brain development, including neuronal maturation and variations in this gene have been shown to be associated with increased risk for mental disorders, particularly schizophrenia. Replication and functional studies of these findings are warranted.

Predictors of mortality in patients with pyogenic liver abscess

BACKGROUND

Pyogenic liver abscess (PLA) is uncommon but potentially life-threatening. The objective of this study was to identify the prognostic factors for PLA.

METHODS

The medical records of 253 patients, 148 men and 105 women with a mean age of 56.4 years (SD : 15.0 years), who were hospitalised due to a PLA between January 1995 and June 2007 were reviewed. The underlying medical disorders, clinical signs and symptoms, laboratory values, imaging studies, microbiological features, treatments, morbidity and mortality were recorded. Factors related to in-hospital case fatality were analysed.

RESULTS

The mean Acute Physiology And Chronic Health Evaluation (APACHE) II score at admission in patients with PLA was 8.7 points (SD 5.4 points). The most common co-existing disease was diabetes mellitus (41.9%), followed by biliary stone disorders (32.0%). Klebsiella pneumoniae was the most frequent pathogen, followed by Escherichia coli. The in-hospital case-fatality rate was 9.1%. Multivariate analysis revealed that gas-forming abscess (p=0.019), multi-drug resistant isolates (p=0.026), anaerobic infection (p=0.045), blood urea nitrogen level >7.86 mmol/l (p=0.004), and APACHE II score > or =15 (p= 0.004) were associated with mortality.

CONCLUSIONS

The prognosis of PLA may depend chiefly on the severity of the basic physical condition and underlying pathology. As the primary treatment for PLA is not completely effective, a more aggressive approach should be considered, especially for patients with poor prognosis.

Expression of sex-determining genes in human sebaceous glands and their possible role in the pathogenesis of acne

BACKGROUND

The human skin, especially the sebaceous gland, is a steroidogenic organ similar to the gonads and adrenal cortex, possessing all the enzymes required for steroid sex-hormone synthesis and metabolism. Factors regulating cutaneous steroidogenesis associated with disease status remain largely unknown.

OBJECTIVE

We hypothesized that transcription factors involved in sex formation and regulation of steroidogenesis in the classical steroidogenic organs are also expressed in the sebaceous glands. Their possible role in the pathogenesis of acne were investigated.

METHODS

We used reverse transcription polymerase chain reaction (RT-PCR), in situ hybridization and Western blotting to analyse the expression of SF-1, WT-1, SRY, SOX-9 and DAX-1 mRNAs and their proteins in cultured human sebocytes and the facial skin of acne patients.

RESULTS

The in situ hybridization study showed SOX-9 mRNA mainly localized in basal keratinocytes, the basal layer of the sebaceous glands and eccrine glands. Immortalized human sebaceous gland cells (SZ95) expressed mRNA for SOX-9, WT-1 and DAX-1 but not for SF-1 or SRY. The expression of DAX-1 protein was slightly inhibited by 10(-6) m oestradiol (E2) at 6 h but enhanced by 10(-6) m dihydrotestosterone (DHT) at 48 h. The facial expression of SOX-9 seemed to be higher in the acne-prone male patients, while DAX-1 was stronger in subjects without acne, although both were statistically insignificant.

CONCLUSION

Our findings confirm the expression of some sex-determining genes in human sebaceous glands. Further studies on a larger patient population including the normal controls are needed to elucidate the functional significance of these transcription factors in the pathogenesis of acne.

The recovery of some components of the renin angiotensin system in the rat pancreas after chronic exposure to hypoxic condition

Previous studies have shown that the expression of the major components from a local pancreatic renin-angiotensin system (RAS) was upregulated after chronic exposure to oxygen deprivation (10% oxygen). In the present study, the reversibility of expression for the pancreatic RAS affected by chronic hypoxia was investigated in the pancreas. Rats were first subject to hypoxia for one Month and they were then returned to normoxic conditions for a varying period of time (1, 2, 3 and 4 weeks). The degree of recovery in the expression of RAS components was analyzed with standard curve-quantitative competitive-reverse transcription-polymerase chain reaction (SC-QC-RT-PCR), Western blot analysis and a specific assay for angiotensin-converting enzyme (ACE) activity. Results from SC-QC-RT-PCR showed that the upregulated expression of angiotensin II type 1 (AT(1)) receptor mRNA following chronic hypoxia could be completely restored to the control level after the rats were returned to the normoxic condition for 3 weeks. The reversibility of mRNA expression for angiotensin II type 2 (AT(2)) receptor and angiotensinogen was observed after the return to normoxic conditions for 2 and 3 weeks respectively when compared with that of their respective controls. Results from Western blot analysis further confirmed that the expression of AT(1) receptor protein was also reversible after return to normoxic conditions for 4 weeks. In addition, the activation of ACE activity returned to its normal level in a time-dependent manner. These data indicate that the upregulation of a local pancreatic RAS affected by chronic hypoxia could be recoverable. The significance of its reversibility and adaptability following chronic hypoxia may be of physiological relevance to the pancreas.

Acute reduction in serum progesterone concentrations after feed intake in dairy cows

This study tested the hypothesis that high feed consumption will acutely decrease circulating progesterone concentrations. In the first experiment, a Latin Square design was used to test whether feeding pattern would alter circulating progesterone in pregnant lactating Holstein cows (n = 12). Feed was removed for 12h before the experiment and cows were then either fed 100% of the total mixed ration (TMR), 50% of TMR every 12h, 25% of TMR every 6h, or left unfed for an additional 12h. Blood samples were taken every hour for 24h. Provision of 100 or 50% of TMR decreased circulating progesterone by 1h after feeding and progesterone remained depressed until 8-9h after feeding. Feeding 25% of TMR did not reduce circulating progesterone concentrations. Experiment 2 used a crossover design to measure the effect of acute feeding on circulating progesterone and LH concentrations during delivery of a constant amount of exogenous progesterone (Eazi-Breed CIDRs) in lactating Holstein cows (n = 8) and nonpregnant dry Holstein cows (n = 6). Blood samples were taken every 15min for 8h. There was no change in serum progesterone during the 8h treatment period in unfed cows; however, feeding decreased (P<0.05) circulating progesterone between 2 and 6h after feeding. In lactating cows, feeding increased mean LH (P<0.05). There were more LH pulses (P = 0.01) in lactating than nonlactating cows. Thus, acute feeding reduced circulating progesterone in pregnant lactating cows apparently due to an increase in progesterone metabolism. Interestingly, feeding multiple smaller meals eliminated the acute effect of feeding on circulating progesterone.

Association study of the dopamine and serotonin transporter genetic polymorphisms and methamphetamine abuse in Chinese males

The dopamine transporter (DAT) and the serotonin transporter (5-HTT) play important roles in methamphetamine (METH) dependence because they are the target of METH action. For this study, the association between the DAT and 5-HTT polymorphisms and METH dependence were investigated for a Chinese-male sample population. The investigated polymorphisms included those of the DAT 3'-variable number tandem repeat, the 5-HTT gene promoter and a 5-HTT variable number tandem repeat polymorphisms. No significant difference was demonstrated for genotype or allele frequency, when comparing METH dependent and control cases for the DAT and the 5-HTT polymorphisms. The findings of this study suggest that these polymorphisms do not play major roles in METH dependence in the Chinese-male population.

Expression of DAZL protein in the human corpus luteum

The DAZL gene and its homologues are required for the development of male and female germ cells in different species. However, their role in other aspects of human reproduction is not known. We have generated a polyclonal antibody to the DAZL protein and developed a sensitive standard curve quantitative-competitive-RT-PCR assay to characterize the expression of DAZL in the human corpus luteum (CL). DAZL transcripts are expressed in the CL, but the concentrations decreased with advancing luteal phase. In accordance with the mRNA data, DAZL protein was most abundant in the early phase CL. Immunohistochemical staining showed DAZL protein in the cytoplasm of granulosa-luteal cells. The distinct expression pattern of DAZL protein in the human CL may play an important role in the regulation of luteal function.

Regulation of progesterone and prostaglandin F2alpha production in the CL

After the luteinizing hormone (LH) surge, the cells that remain from the ovulated follicle undergo a process of differentiation termed luteinization. Two key features of the cells after luteinization are the capacity for tremendous production of progesterone [10(16) molecules of progesterone per (min/(g of CL))] and the capacity to undergo regression or death of the cells at the appropriate time. There are two steroidogenic cell types, the small and large luteal cells that are regulated by different mechanisms. In small luteal cells, production of progesterone is stimulated by LH through the protein kinase A (PKA) pathway. The large luteal cells of ruminants produce large quantities of progesterone that is independent of LH stimulation. Although luteotrophins clearly regulate luteal function, much of luteal progesterone production in some species appears to be constitutive, consistent with the autonomous aspects of the large luteal cell. The key regulated step in luteal progesterone production appears to be regulation of transport of cholesterol to the inner mitochondrial membrane apparently mediated by the steroidogenic acute regulatory protein (StAR). In addition, our recent research indicates that PKA is tonically active in large luteal cells and this may be responsible for the high, relatively autonomous nature of luteal progesterone production. Regression of the corpus luteum (CL) in many species is initiated by prostaglandin (PG) F2alpha secreted from the uterus. Luteal cells also have the capacity for production of PGF2alpha. Luteal PGF2alpha production can be regulated by a variety of substances including inhibition by progesterone and stimulation by cytokines. We have also characterized a positive feedback pathway in ruminant and porcine CL in which small amounts of uterine PGF(2alpha) stimulate intraluteal production of PGF2alpha due to induction of the cycloxygenase-2 (Cox-2) enzyme in large luteal cells. This positive feedback pathway is only present in CL that has acquired the capacity for luteal regression ( approximately day 7 in cow, approximately day 13 in pig). Regulation by protein kinase C (PKC) of transcriptional factors interacting with an E-box in the 5' flanking region of the Cox-2 gene is the critical regulatory element involved in this positive feedback pathway. Thus, luteinization in some species appears to change specific gene transcription such that progesterone production becomes relatively independent of acute luteotrophic regulation and intraluteal PGF2alpha synthesis is induced by the second messenger pathways that are activated by PGF2alpha.

Association study of the 5-HT(6) receptor polymorphism (C267T) and symptomatology and antidepressant response in major depressive disorders

The serotonergic neurotransmitter system has been implicated in the pathogenesis of major depressive disorder (MDD). Of the 14 human serotonin (5-HT) receptors, the 5-HT(6) receptor may be a candidate for the study of MDD because of its relative abundance in certain limbic areas and its high affinity to several antidepressants. The present study tested the hypothesis that a 5-HT(6) genetic polymorphism (C267T) is associated with the clinical manifestations of, and/or antidepressant response in, MDD. The Hamilton Depression Rating Scale was used to assess 57 MDD patients before antidepressant treatment, with 34 patients completing the 4-week treatment and evaluation. The results of the association study provide that the 5-HT(6) C267T genetic variant does not play a major role in producing the clinical manifestations or antidepressant response for MDD patients. Further study with a functional 5-HT(6) polymorphism is needed to explore the role of 5-HT(6) in the pathogenesis of MDD.

A study of alpha-adrenoceptor gene polymorphisms and Alzheimer disease

There exists considerable evidence implicating abnormalities of the alpha (alpha)-adrenergic system in the development of Alzheimer disease (AD). We propose to investigate potential correlations between the presence or otherwise of alpha-adrenoceptor polymorphisms and the presence of AD. We studied the polymorphisms of the alpha1a- and the alpha2a-adrenoceptor genes in 142 AD patients and 98 normal controls. The result demonstrated that none of the alpha2a-adrenoceptor genotypes was associated with increased susceptibility to AD. However, there was a trend that the frequency of the C allele of the alpha1a-adrenoceptor was elevated and an excess of the CC genotype (90.1%) was found in the subjects with AD in comparison with the controls (78.6%). This association was unrelated to the apolipoprotein E genotypes. The hypothesis that the alpha1a-adrenoceptor gene may be implicated in the pathogenesis of AD may deserve further study.

Association study of the p53-gene Pro72Arg polymorphism in schizophrenia

The p53 tumor-suppressor gene, encoding a phosphoprotein, is a key element in maintaining genomic stability and cell apoptosis. It is also implicated in nervous-system development. In order to examine the role of the p53 gene for the pathogenesis of schizophrenic disorders, patients (n=155) and control subjects (n=168) were genotyped for the p53-Pro72Arg polymorphism. The results demonstrated no association with schizophrenia and/or age of onset for this polymorphism.

Association study between cannabinoid receptor gene (CNR1) and pathogenesis and psychotic symptoms of mood disorders

Cannabis can induce mood change and sometimes psychotic symptoms in normal persons. In brain, the main active ingredient of cannabis acts via the cannabinoid CB1 receptor (CNR1) which is located on chromosome 6q14-15. Linkage studies have suggested the presence of a bipolar disorder susceptibility locus on chromosome 6q. In this population based association study, we tested the hypothesis that a microsatellite polymorphism in the promoter region of the CNR1 gene confers susceptibility to mood disorders and psychotic features. We genotyped the CNR1 gene is 154 mood disorder patients and 165 normal controls. The results showed that the triplet repeat polymorphism in the promoter region of the CNR1 gene was not likely to be involved in the pathogenesis or in the psychotic symptoms of mood disorders.

Association analysis for NMDA receptor subunit 2B (GRIN2B) genetic variants and psychopathology and clozapine response in schizophrenia

It is known that a syndrome resembling schizophrenia is produced by the N-methyl-d-aspartate receptor antagonists. It has also been demonstrated that the level of an ionotropic N-methyl-d-aspartate 2B subunit (GRIN2B) of the glutamate receptor tends to increase after subchronic administration of clozapine, suggesting that GRIN2B may play an active role in the pathogenesis of schizophrenia and the function of clozapine medication. We studied 100 schizophrenic patients, investigating the associations for the GRIN2B genetic variants, and psychiatric symptoms and clozapine response. No significant differences were demonstrated comparing these three groups in terms of the baseline Brief Psychiatric Rating Scale (BPRS) score (P = 0.441). The percentage of patients scoring within 20% of baseline BPRS after clozapine treatment was similar for the three genotype groups (P = 0.132). A marginally higher mean clozapine dosage was revealed, however, for patients bearing the 2664C/C genotype (P = 0.013). Although replication of this research is required to confirm the results, an association for the GRIN2B C2664T polymorphism and clozapine treatment is suggested from our findings, which may assist in the prediction of optimal dosage for schizophrenic patients.

The efficacy and safety of risperidone for the treatment of geriatric psychosis

Risperidone is an atypical antipsychotic drug which has been suggested to be beneficial for the treatment of elderly patients with psychotic symptoms. In this study, we assessed the short-term efficacy and the safety of risperidone in geropsychiatric inpatients with psychotic symptoms. The sample population included 110 elderly inpatients with psychotic disorders. Assessment for drug efficacy using the Brief Psychiatric Rating Scale, Sandoz Clinical Assessment-Geriatric scale, and Clinical Global Impression scale was conducted at baseline and also at 4 weeks subsequent to risperidone treatment commencement. Subsequent to commencing risperidone treatment, 80 patients completed a 4-week therapeutic evaluation. Seventy (87.5%) of the 80 patients experienced mild to substantial improvement using the Clinical Global Impression scale. Adverse effects were monitored in all 110 patients. The most commonly detected adverse effects were weakness of legs or walking problems (43/110; 39.1%) and dizziness (32/110; 29.1%). Peripheral edema was noted in 18 (16.4%) patients. Risperidone, in low doses, appeared to have been effective in this sample of patients older than 65 years with psychotic symptoms. The mean dose (2.1 +/- SD 1.4 mg/day) applied was lower then that suggested for young patients and was related to the each specific patient diagnosis. Peripheral edema and walking problems were commonly observed adverse effects for these elderly patients, such problems having not been seen to the same extent in previous studies of young patients.

Regulation of steroidogenic acute regulatory protein expression and progesterone production in endometriotic stromal cells

The regulation of steroidogenic acute regulatory protein (StAR) gene expression and the synthesis of steroids from cholesterol in ectopic endometriosis tissues were investigated. Peritoneal fluid and endometrial tissues were collected from patients with endometriosis and otherwise healthy women. Peritoneal progesterone and 17 beta-E2 concentrations were highest in early stage endometriosis compared with those in advanced stage endometriosis and in normal women. In concordance with the profile of peritoneal steroids, StAR mRNA and protein were greatest in ectopic implants of early endometriosis. In the advanced stage, concentrations of StAR mRNA and protein were also greater compared with those in normal endometrium. In contrast, P450 side-chain cleavage enzyme and 3 beta-hydroxysteroid dehydrogenase transcripts were not different between normal endometrium and ectopic endometriotic implants. Expression of StAR mRNA was detected in purified stromal, but not epithelial, cells. Treatment with PGE(2), but not TNF alpha, or IL-1 beta significantly increased StAR expression and thus induced progesterone production in cultured endometriotic stromal cells. These results demonstrated that aberrant expression of StAR in ectopic endometriotic tissues leading to increased peritoneal progesterone is associated with the formation of endometriosis. Induction of StAR gene expression by peritoneal PGE(2) in endometriotic stromal cells may further contribute to the development of endometriosis.

The upregulation of angiotensin II receptor AT(1) in human preeclamptic placenta

The human placenta has been considered to possess a locally generated renin-angiotensin system (RAS), which may play a physiological role in the regulation of uteroplacental blood circulation. The changes in the expression of such a placental RAS during pregnancy could be important for the physiological and pathophysiological aspects of some clinical disorders, such as pregnancy-induced hypertension, preeclampsia. In the present study, the alterations of expression and localization of placental angiotensin II receptor subtypes, namely AT(1) in patients with preeclampsia (elective caesarean delivery) were investigated and compared with controls (vaginal delivery and elective caesarian delivery) using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR), Western blot and immunohistochemistry respectively. Results from RT-PCR analysis revealed an upregulated expression of placental mRNA for AT(1) receptor subtype in patients with preeclampsia when compared with those in controls. In addition, there was also a significant activation of placental expression of angiotensinogen mRNA in patients with preeclampsia. Results from Western blot showed that the expression of AT(1) receptor was also upregulated. Immunohistochemical results further demonstrated that increased immunoreactivity for placental AT(1) receptor was predominantly localized to the thin layers of syncytiotrophoblasts and, to a less extent, the capillaries of the term placental villi. These data indicate that upregulation of placental RAS components, notably AT(1) receptor in the syncytiotrophoblasts, could play a pathophysiological role in patients with preeclampsia.

Association analysis of a functional G protein beta3 subunit gene polymorphism (C825T) in mood disorders

The guanine nucleotide-binding proteins (G proteins), heterotrimers consisting of alpha, beta and gamma subunits, convey signals initiated by the activation of many neurotransmitter receptors. Evidence for involvement of the G proteins in mood disorders relies on the effects of mood stabilizers and antidepressants on G protein function. In addition, abnormalities in the expression of G proteins have been demonstrated in mood disorder patients. Therefore, we tested the hypothesis that a functional polymorphism (C825T) in the G protein beta3 gene subunit (GNB3) confers susceptibility to mood disorders. A population-based association study was utilized, and GNB3 was genotyped for 144 mood disorder patients and 153 normal controls. The results reveal that it is not likely that the C825T polymorphism in the GNB3 gene subunit is involved in mood disorder pathogenesis. Further studies of the associations between other G protein subunits and mood disorder are needed to fully elaborate the involvement of this protein in mood disorders.

Characteristics of Chinese suicide attempters admitted to a geropsychiatric unit

PURPOSE

To investigate the characteristics for elderly Chinese suicide attempters in Taiwan and make comparisons with Western reports.

METHODS

During a six-year period, patients admitted to a geropsychiatric unit as a result of a suicide attempt were investigated for factors related to the suicide attempt.

RESULTS

Of the 722 admissions during this period, 55 (7.6%) were patients who had been admitted due to suicide attempt. The sex and age distributions for the suicide attempters were similar to those for other patients. The most common diagnoses were depressive disorders (56.4%), followed by delusional disorders (20.0%). A total of 121 suicide motives were cited for the 55 attempters, an average of 2.2 per person, with depressive symptoms commonly found on admission. During the first week of hospitalization, 53 attempters (96.4%) still exhibited suicidal ideation and six patients made a further suicide attempt, however, only three patients retained suicidal ideation on discharge.

CONCLUSIONS

Our study confirms previous Western reports that depressive disorders are commonly manifested in elderly suicide attempters. There were differences in the motives and methods employed for the suicides, possibly due to cultural difference and/or sample source. Most of the suicide attempters exhibited a favourable response with hospitalization.

Expression patterns and transcript concentrations of the autosomal DAZL gene in testes of azoospermic men

The DAZ (Deleted in AZoospermia) gene cluster on the Y chromosome is a strong candidate for the azoospermia factor. The DAZ gene was derived from an autosomal homologue, DAZL (DAZ-Like). This study was designed to assess the functional role of DAZL in human spermatogenesis. The expression patterns and mRNA transcript levels of DAZL in the testes of 17 azoospermic men were therefore examined by immunohistochemical staining and quantitative competitive reverse transcription-polymerase chain reaction. DAZL protein was expressed in the cytoplasm of primary spermatocytes and weakly in spermatogonia. It was detected in the testicular tissues of all subjects with germ cells present. The copy number of the DAZL transcript in normal spermatogenesis (n = 4), hypospermatogenesis or maturation arrest (n = 6), and Sertoli cell-only syndrome (n = 7) ranged from 1.22 x 10(6) to 1.63 x 10(6) per ng of RNA, 1.19 x 10(5) to 2.82 x 10(5) per ng of RNA and 2.83 x 10(4) to 1.23 x 10(5) per ng of RNA respectively. DAZL transcripts were lower in men with spermatogenic failure, and a significant difference was found between the three groups (P < 0.0001). This study suggests that DAZL may play an important role in the human spermatogenic processes of both mitosis and meiosis.

Effects of Cordyceps sinensis on testosterone production in normal mouse Leydig cells

The stimulatory effect of Cordyceps sinensis (CS) on MA-10 mouse Leydig tumor cell steroidogenesis was previously demonstrated in our laboratory. In the present studies, we further determined the effect of CS on steroidogenesis in purified normal mouse Leydig cells. Different concentrations of CS (0.1-10 mg/ml) were added to Leydig cells without or with human chorionic gonadotropin (hCG) (50 ng/ml), and the steroid production was determined by radioimmunoassay (RIA). The results illustrated that CS stimulated normal mouse Leydig cell steroidogenesis in a dose-dependent relationship. CS at 3 mg/ml significantly stimulated testosterone production (p<0.05). Concerning the temporal relationship, CS at 3 mg/ml stimulated maximal testosterone production between 2 to 3 hr. Interestingly, hCG-stimulated testosterone productions were suppressed by CS in a dose-dependent relationship. CS also reduced dbcAMP-stimulated testosterone productions, which indicated that CS affected signal transduction pathway of steroidogenesis after the formation of cyclic AMP. Moreover, cycloheximide inhibited CS-treated mouse Leydig cell testosterone production, suggesting that new protein synthesis was required for CS-stimulated steroidogenesis.

Association between the Ser9Gly polymorphism of the dopamine D3 receptor gene and tardive dyskinesia in Chinese schizophrenic patients

It has been suggested that dopamine D3 receptor (DRD3) may have important implications for antipsychotic-induced tardive dyskinesia (TD). Previous studies have demonstrated an association between a serine to glycine polymorphism in the first exon of the DRD3 gene and TD; however, the results have been inconsistent. Therefore, we have replicated these studies using a Chinese sample population. A total of 115 schizophrenic patients from chronic wards were assessed for TD severity using the Abnormal Involuntary Movements Scale (AIMS) and were subsequently genotyped for the DRD3 polymorphism. The mean AIMS score for patients carrying the heterozygote (DRD3(ser-gly)) was significantly greater than for those with the homozygotes (DRD3(ser-ser) and DRD3(gly-gly)). Our results are in line with a previous report, the results of which suggest that the presence of the DRD3(ser-gly) genotype may be a risk factor for the development of TD in patients treated with antipsychotics.

Association analysis of the partially duplicated alpha7 nicotinic acetylcholine receptor genetic variant and Alzheimer's disease

Changes in the nicotinic acetylcholine receptors (nAChRs) have been demonstrated for Alzheimer's disease (AD). Of these receptors, the alpha7 nAChRs, which are abundant on hippocampal interneurons, have been implicated in the cytotoxic role of the beta-amyloid. Increased mRNA levels of alpha7 nAChR in the peripheral lymphocytes and hippocampus of AD patients have been reported. We tested the hypothesis that the allelic variant, 2bp deletion, of the partially duplicated alpha7 nAChR gene confers susceptibility to Alzheimer's disease. The -2bp polymorphism was examined in 120 patients with AD and 98 normal controls. The distribution of the partially duplicated alpha7 nAChR genotypes (p = 0.372) and alleles (p = 0.465) did not differ significantly for AD patients and controls. This negative finding suggests that the partially duplicated alpha7 nAChR genetic polymorphism contributes no major effect to the development of AD. However, we suggest that the other genetic variation of the alpha7 nAChR gene, related to AD or the associated symptomatology, merits further investigation.

Association study of nicotinic-receptor variants and major depressive disorder

BACKGROUND

Depressive patients are more likely to smoke than the general population and nicotine was found to reduce the incidence and severity of depressive symptoms in many studies. These findings suggest that nicotinic acetylcholine receptors (nAChRs) may be implicated in major depressive disorder. We tested the hypothesis that the allelic variant, 2 bp deletion, of the partially duplicated alpha7 nAChR gene confers susceptibility to major depressive disorder.

METHODS

We genotyped alpha7 nAChR in 72 patients with major depressive disorder and 103 normal controls.

RESULTS

The distribution of the partially duplicated alpha7 nAChR genotypes (P=0.027) and alleles (P=0.037) suggests a modest difference between depressive patients and controls.

LIMITATIONS

The -2 bp allele is thought to be present only in the duplicated exon 6, and the impact of the partially duplicated alpha7 nAChR and its -2 bp variant remain to be determined.

CONCLUSIONS

The -2 bp allele of partially duplicated alpha7 nAChR may have an influence on the risk for development of major depressive disorder. The levels of significance achieved are modest and the findings must be replicated in other studies.

Association study of angiotensin-converting enzyme gene polymorphism with schizophrenia and polydipsia

Angiotensin-converting enzyme (ACE) is a key enzyme in the renin-angiotensin system and can modulate dopamine turnover in the midbrain. Previous studies have revealed changes in the central ACE levels for schizophrenic patients, possibly related to the polydipsia commonly demonstrated for chronic schizophrenia. An insertion (I)/deletion (D) polymorphism of the ACE gene has been associated with ACE levels. Therefore, we elected to investigate the ACE I/D polymorphism for 124 schizophrenic patients and 117 control subjects. No significant differences for the genotype distribution or the allele frequency were revealed comparing controls and schizophrenic patients. The ACE genotypes were not associated with onset age or psychiatric symptoms for the schizophrenic cases. A modest association was revealed for this ACE polymorphism and polydipsia diagnosis for these patients. Using bearers of the D allele as baseline, the ratio for I/I homozygote was 2.31 (95% CI 0.95-5.65). This association needs further replication as it may have implications for the pathogenesis and the treatment of polydipsia for schizophrenic patients.

Reduced regional [14C]2-deoxyglucose uptake in response to long-term clozapine administration in rats

Clozapine has superior effects in treating negative symptoms of schizophrenia and causes less extrapyramidal side effects than traditional antipsychotics. In this study, we investigated the effects of acute and long-term clozapine administration on [14C]2-deoxyglucose uptake (2-DG uptake) in rats, as measured using the [14C]2-deoxy-D-glucose method. The 2-DG uptake was reduced in fewer regions after chronic clozapine (46%) than after acute clozapine (97%). After chronic clozapine treatment, the 2-DG uptake was reduced in the shell, but not the core, of the nucleus accumbens. In addition, long-term clozapine treatment remained affecting 2-DG uptake in several regions of the extrapyramidal system and the thalamus. The pattern of 2-DG uptake changes after long-term clozapine administration may provide information for the regions related to the therapeutic effect of clozapine.

Association study for a functional serotonin transporter gene polymorphism and late-onset Alzheimer's disease for Chinese patients

Two recent studies have demonstrated an association for a deletion/insertion polymorphism within the promoter region of the serotonin transporter gene (5-HTTLPR), and Alzheimer's disease (AD). According to these studies, subjects with the short variant of the 5-HTTLPR gene are at increased risk for AD; however, this finding has not been confirmed by other workers. To evaluate the role of the 5-HTTLPR gene in susceptibility for AD, we conducted an association study for this polymorphism in a Chinese population. No significant differences were determined for genotype distribution or allele frequencies, comparing AD patients and normal controls. Even dividing the population into subgroups according to the presence of the APOE epsilon4 allele, no differences for genotype or allele frequencies were determined, comparing patients and controls. These results suggest that it is unlikely that the 5-HTTLPR polymorphism plays a substantial role in conferring susceptibility to AD.

Association analysis of the 5-HT6 receptor polymorphism C267T with depression in patients with Alzheimer's disease

A significant increase of 267C allele of the 5-HT(6) receptor gene has been reported in patients with Alzheimer's disease (AD). Because a deficit in serotonergic neurotransmission is involved in major depression, we tried to find out whether 267C allele is associated with depressive disorders in AD. A psychiatrist interviewed all AD patients and their caregivers for evidence of depression using a Chinese version of the Standard Clinical Interview for DSM-III-R. The difference in the 5-HT(6) genotype or allele distributions between the AD patients with depressive disorders (n = 25) and those without (n = 120) was not significant.

Differential effects of prostaglandin F2alpha on in vitro luteinized bovine granulosa cells

Prostaglandins have been implicated in various aspects of ovarian function including ovulation and luteolysis. In this study, the expression and regulation of inducible prostagland in G/H synthase (PGHS-2) and PGF(2alpha) receptors were investigated in bovine granulosa cells at various stages of differentiation. Firstly, the induction of PGF(2alpha) receptor mRNA and PGHS-2 mRNA in preovulatory granulosa cells was evaluated. Granulosa cells were collected from preovulatory follicles and cultured for 1, 4, 7 or 10 days. Cells were treated with hCG (10 iu) or with increasing doses of forskolin (0-10 micromol l(-1)) for 24 h. Forskolin increased steady-state concentrations of mRNA for PGHS-2 (> 20-fold) and PGF(2alpha) receptor (> 1000-fold) in a dose-dependent fashion. Use of selective protein kinase A inhibitor (H89) reduced both hCG- and forskolin-induced expression of PGF(2alpha) receptor mRNA and PGHS-2 mRNA. The hypothesis that luteinized granulosa cells would acquire PGF(2alpha) responsiveness similar to responses to PGF(2alpha) observed in vivo was also evaluated. Treatment with PGF(2alpha) (100 nmol l(-1)) reduced forskolin-induced expression of PGF(2alpha) receptor mRNA on days 4, 7 and 10, but not on day 1 of culture (n = 3). Treatment with PGF(2alpha) did not change forskolin-induced expression of PGHS-2 mRNA on or before day 4 of culture. In contrast, PGF(2alpha) significantly increased PGHS-2 mRNA expression in granulosa cells primed with forskolin for 7 or 10 days. In conclusion, expression of PGHS-2 and PGF(2alpha) receptor mRNA is protein kinase A-dependent in preovulatory bovine granulosa cells. Granulosa cells become PGF(2alpha)-responsive soon after expression of PGF(2alpha) receptor, whereas further differentiation is required before PGF(2alpha) induces PGHS-2 mRNA upregulation. These results demonstrate that at least two key transitions are required in PGF(2alpha)-induced luteal regression in the mid-cycle corpus luteum.

Genetic association analysis of alpha-1-antichymotrypsin polymorphism in Parkinson's disease

alpha(1)-Antichymotrypsin (ACT) gene has been suggested as a susceptibility factor for Parkinson's disease (PD) and might be related to the onset of PD. We replicated these findings in a Chinese population. The results demonstrated that the ACT genotypic and allelic distributions showed no significant differences between the PD patient and the control groups. The age at onset was younger in the heterozygotes than in the homozygotes (p = 0.042). We suggest that the ACT polymorphism might play some role in the pathogenesis of PD, especially in the onset.

Temporal gene expression in bovine corpora lutea after treatment with PGF2alpha based on serial biopsies in vivo

There is growing evidence to indicate that PGF(2alpha)-induced luteolysis involves altered gene expression in the corpus luteum. Concentrations of mRNA encoding nine different gene products were quantified at three time points from corpora lutea in situ. Serial luteal biopsies (2.1-5.5 mg per biopsy) were collected using an ultrasound-guided transvaginal method and mRNA concentrations were quantified with standard curve quantitative competitive RT-PCR. In the first experiment, three luteal biopsies were collected from three heifers and analysed in multiple assays to evaluate the repeatability of the methods. Concentrations of mRNA for glyceraldehyde 3-phosphate dehydrogenase (GAPDH), PGF(2alpha) receptor (FP receptor) and LH receptor were found to be highly repeatable between assays, between multiple biopsies and between animals (coefficients of variation 1.3-17.3%). In the second experiment, heifers on days 9-11 after ovulation were assigned randomly to receive saline only (n = 6), saline with biopsies taken at t = 0, 0.5 and 4.0 h after injection (n = 6), PGF(2alpha) only (n = 6) or PGF(2alpha) with biopsies taken at t = 0, 0.5 and 4.0 h after treatment (n = 7). Biopsy alone did not change corpus luteum diameter, serum progesterone concentrations or days to next ovulation within the saline- or PGF(2alpha)-treated groups. Concentrations of mRNA for steroidogenic acute regulatory protein, FP receptor, 3beta-hydroxysteroid dehydrogenase, cytosolic phospholipase A(2) and LH receptor were decreased at 4.0 h after PGF(2alpha) injection. In contrast, PGF(2alpha) increased mRNA concentrations for prostaglandin G/H synthase-2, monocyte chemoattractant protein-1 and c-fos but the time course differed for induction of these mRNAs. Concentrations of mRNA for GAPDH did not change after PGF(2alpha) treatment. In conclusion, the techniques allowed analysis of multiple, specific mRNAs in an individual corpus luteum at multiple time points without altering subsequent luteal function. Use of these techniques confirmed that luteolysis involves both up- and downregulation of specific mRNA by PGF(2alpha).

Temporal gene expression in bovine corpora lutea after treatment with PGF2alpha based on serial biopsies in vivo

There is growing evidence to indicate that PGF(2alpha)-induced luteolysis involves altered gene expression in the corpus luteum. Concentrations of mRNA encoding nine different gene products were quantified at three time points from corpora lutea in situ. Serial luteal biopsies (2.1-5.5 mg per biopsy) were collected using an ultrasound-guided transvaginal method and mRNA concentrations were quantified with standard curve quantitative competitive RT-PCR. In the first experiment, three luteal biopsies were collected from three heifers and analysed in multiple assays to evaluate the repeatability of the methods. Concentrations of mRNA for glyceraldehyde 3-phosphate dehydrogenase (GAPDH), PGF(2alpha) receptor (FP receptor) and LH receptor were found to be highly repeatable between assays, between multiple biopsies and between animals (coefficients of variation 1.3-17.3%). In the second experiment, heifers on days 9-11 after ovulation were assigned randomly to receive saline only (n = 6), saline with biopsies taken at t = 0, 0.5 and 4.0 h after injection (n = 6), PGF(2alpha) only (n = 6) or PGF(2alpha) with biopsies taken at t = 0, 0.5 and 4.0 h after treatment (n = 7). Biopsy alone did not change corpus luteum diameter, serum progesterone concentrations or days to next ovulation within the saline- or PGF(2alpha)-treated groups. Concentrations of mRNA for steroidogenic acute regulatory protein, FP receptor, 3beta-hydroxysteroid dehydrogenase, cytosolic phospholipase A(2) and LH receptor were decreased at 4.0 h after PGF(2alpha) injection. In contrast, PGF(2alpha) increased mRNA concentrations for prostaglandin G/H synthase-2, monocyte chemoattractant protein-1 and c-fos but the time course differed for induction of these mRNAs. Concentrations of mRNA for GAPDH did not change after PGF(2alpha) treatment. In conclusion, the techniques allowed analysis of multiple, specific mRNAs in an individual corpus luteum at multiple time points without altering subsequent luteal function. Use of these techniques confirmed that luteolysis involves both up- and downregulation of specific mRNA by PGF(2alpha).

Effects of organosulfur compounds from garlic oil on the antioxidation system in rat liver and red blood cells

The modulation of garlic oil (GO) and three allyl compounds, diallyl sulfide (DAS), diallyl disulfide (DADS) and diallyl trisulfide (DATS), on the antioxidation system in rat livers and red blood cells was examined. Rats were orally administered GO (200 mg/kg body weight), DAS (20, 80 mg/kg body weight), DADS (80 mg/kg body weight) or DATS (70 mg/kg body weight) three times a week for 6 weeks. Control rats received corn oil (2 ml/kg body weight) alone. GO, DADS and DATS treatment significantly increased the glutathione (GSH) content (48-84%) in red blood cells (P < 0.05). DATS displayed a greater enhancement than GO and DADS (P < 0.05). Hemolysis induced by tert-butyl hydroperoxide was not suppressed by GO or allyl compound treatment although higher GSH content was evident. Hepatic GSH was not influenced by garlic components. In rat livers, DADS and DATS significantly increased the activity of GSH reductase (46 and 54%, respectively) and of GSH S-transferase (GST) (63 and 103%, respectively), but decreased the GSH peroxidase activity (27 and 28%, respectively). In contrast, GSH reductase and GST activities in the DAS group, either 20 or 80 mg/kg body weight, were similar to the control group. A decrease of GSH peroxidase activity was observed in rats dosed with 80 mg/kg body weight (P < 0.05). An increase in GST activity and a decrease in GSH peroxidase activities were also noted in GO-treated rats (P < 0.05). In red blood cells, three GSH-related antioxidant enzyme activities were not affected by garlic oil and its organosulfur components. Immunoblot assay showed that, accompanying the increase in hepatic GST activity, GO, DADS, DAS (80 mg/kg body weight) and DATS increased the expression of GST Ya, Yb1 and Yc proteins. Results indicate that GO and three allyl compounds play a differential role in modulation of the GSH-related antioxidant system in rat livers and red blood cells.

Estrogen receptor alpha gene polymorphism in schizophrenia: frequency, age at onset, symptomatology and prognosis

Schizophrenic disorders are equally distributed for both sexes; however, later onset, milder psychopathology and better outcome are associated with the female gender. This sex difference is thought to be partly due to the estrogen system. Recent studies have determined that estrogen receptor alpha subtype (ER alpha) genetic polymorphisms may affect the expression of ER alpha, and are associated with Alzheimer's disease. For this study, we investigated the association of ER alpha polymorphisms for 125 schizophrenic patients and 142 control subjects. No significant differences for genotype distribution or allele frequency were revealed comparing controls and schizophrenic patients. The ER alpha genotypes were not associated with onset age, psychiatric symptoms or outcome for schizophrenic cases. With new research highlighting the prominent role of sex hormones in neurological and psychological dysfunction, further study is needed to explore the genetic effect of the sex hormone receptor gene on susceptibility mental disorders and associations with different phenotypes.

Effect of diallyl sulfide and diallyl disulfide, the active principles of garlic, on the aflatoxin B(1)-induced DNA damage in primary rat hepatocytes

The objective of this study was to investigate the effect of the active principles in garlic-- diallyl sulfide (DAS) and diallyl disulfide (DADS)--on aflatoxin B(1) (AFB(1))-induced DNA damage in primary rat hepatocytes. Primary rat hepatocytes, induced with DNA damage using 10 microM AFB(1) were used as an experimental model. According to the results of LDH leakage, 0.5 and 2 mM of DAS or 0.5 and 1 mM of DADS significantly increased the viability of hepatocytes compared with the AFB(1) controls after 4, 8 and 24 h treatment (P<0.05). According to the results of unscheduled DNA synthesis (UDS) test, 0.5 and 2 mM of DAS or 0.5 and 1 mM of DADS could significantly decrease the DNA damage induced by AFB(1) (P<0.05). Furthermore, 0.5 and 2 mM DAS or 0.5 and 1 mM DADS could increase the glutathione S-transferase (GST) and glutathione peroxidase (GPx) activities as compared with the AFB(1) controls after 24 h treatment (P<0.05). Results of immunoblot analysis of cytosolic GST isoenzyme indicate that the levels of GST isoform Ya, Yb2 and Yc were markedly increased after treatment with 0.5 and 2 mM DAS or 0.5 and 1 mM DADS compared with the AFB(1) control. These results indicate that 0.5 and 2 mM DAS or 0.5 and 1 mM DADS might protect hepatocytes from AFB(1)-induced DNA damage via increasing the activities of GST and GPx.

Evidence for an association between polymorphism in the serotonin-2A receptor variant (102T/C) and increment of N100 amplitude in schizophrenics treated with clozapine

Using event-related potentials (ERPs), a reduction in the auditory N100, N200 and P300 amplitude has been found in schizophrenic patients and may represent some pathophysiological deficit. Therefore, we investigated whether the genetic variant of the serotonin-2A receptor is associated with ERP change after clozapine treatment in schizophrenic patients. Ninety-nine schizophrenic patients were included in the study. The results demonstrated that patients with 102C/C genotype have higher N100 amplitude than other patients after clozapine treatment. Our findings suggested that serotonin-2A receptor polymorphism may relate to clozapine response in schizophrenic patients. An objective and reliable tool like ERPs to assess patients' treatment response may afford more consistent results in pharmacogenetic studies.

Distinct regulation of gene expression by prostaglandin F(2alpha) (PGF(2alpha)) is associated with PGF(2alpha) resistance or susceptibility in human granulosa-luteal cells

The effects of human chorionic gonadotrophin (HCG) and prostaglandin F(2alpha) (PGF(2alpha)) on regulation of human granulosa-luteal cell (GLC) function at different stages of differentiation (day 2 versus day 8 of culture) were studied. Expression of LH receptor mRNA and biosynthesis of progesterone were HCG dependent in human GLC at all stages (n = 6, P < 0.05). Steady-state concentrations of mRNA encoding for FP (a specific high-affinity plasma membrane receptor for PGF(2alpha)) were not dependent on, but were stimulated by, addition of HCG (10 IU/ml) or 8-bromo-cAMP (0.5 mmol/l) (n = 6, P < 0.05). Treatment with PGF(2alpha) (100 nmol/l) decreased FP mRNA concentration, but had no effect on LH receptor and cyclo oxygenase-2 (COX-2) expression on day 2 of cultured GLC (n = 8). As a result, the progesterone biosynthesis by GLC was not affected. On day 8, PGF(2alpha) induced FP and PGHS-2 expression and at the same time decreased LH receptor expression, resulting in inhibition of progesterone output by GLC. Our data demonstrated that early stage GLC (day 2 of culture) are resistant to PGF(2alpha)-induced inhibition of progesterone synthesis but underwent further differentiation and acquired luteolytic capacity after 8 days culture in vitro. We conclude that, via distinct gene regulation at different stages of differentiation, human GLC may become resistant or susceptible to PGF(2alpha)-induced luteolysis.

Association analysis of polymorphism in the promoter region of the alpha2a-adrenoceptor gene with schizophrenia and clozapine response

There exists considerable evidence implicating the alpha (alpha) adrenergic system in the superior therapeutic effects of clozapine for the treatment of schizophrenia, as also its associated adverse hypersalivation side effect. It would seem plausible for variants of the adrenoceptors to be associated with the clozapine response. The present study tested the hypothesis that a biallelic polymorphism in the promoter region of the alpha2a-adrenoceptor gene confers susceptibility to schizophrenia, and is associated with a clozapine-induced (favorable) therapeutic response and/or a clozapine-induced hypersalivation. Ninety-seven treatment-resistant schizophrenic patients were assessed using the Brief Psychiatric Rating Scale before and after clozapine treatment. The results of clozapine treatment demonstrated that the alpha2a-adrenoceptor gene variants did not play a major role in the susceptibility, hypersalivation adverse effect or clozapine response of patients with schizophrenia. The polymorphism of the alpha2a-adrenoceptor gene investigated is not likely to play a major role in the pathogenesis of schizophrenic disorders or clozapine response, although the hypothesis that these genes are implicated in the cognitive deficit and polydipsia associated with schizophrenic disorders may, however, still warrant further study.

Association between tryptophan hydroxylase gene polymorphism (A218C) and schizophrenic disorders

The human tryptophan hydroxylase (TPH) gene, the rate-limiting enzyme in serotonin biosynthesis, was localized on human chromosome 11p14-p15.3. Variation within intron 7 of the TPH gene was found to influence serotonin metabolism in the brain. To explore the possible role of TPH in the pathogenesis of schizophrenic disorders, we genotyped the TPH A218C polymorphism in 196 schizophrenic patients and 251 controls. The results demonstrated that genotype distribution was significantly different between schizophrenic patients and control subjects (P=0.002). No association was found between TPH genotypes and suicidal history in schizophrenic patients (P=0.239). The positive finding in this study suggests that the TPH 218A allele is a risk factor for schizophrenic disorders or is in linkage disequilibrium with the putative schizophrenia susceptibility locus in Han Chinese population.

Prostaglandin F(2alpha) receptor in the corpus luteum: recent information on the gene, messenger ribonucleic acid, and protein

The prostaglandin (PG) F(2alpha) receptor (FPr) in the corpus luteum is essential for maintaining normal reproductive cyclicity in many species. Activation of this seven-transmembrane spanning receptor at the end of the cycle leads to a decrease in progesterone and the demise of the corpus luteum (luteolysis). Recently, the gene structure of the FPr in three mammalian species has been elucidated; however, promoter regulation of the gene is still poorly understood. The FPr mRNA is extremely low in steroidogenic follicular cells (theca or granulosa) but is expressed at high levels in the corpus luteum, particularly in the large luteal cells. Treatment with PGF(2alpha) decreased FPr mRNA expression in luteal cells in most species that have been studied. Key amino acids have been suggested to be critical for binding of FPr to PGF(2alpha) based on three-dimensional modeling and comparisons with other G-protein-coupled receptors. Moieties of the PGF(2alpha) molecule that are essential for binding or specificity of binding to the FPr have been identified by radioreceptor binding studies. In this article, recent information is reviewed on the structure of the FPr gene, regulation of luteal FPr mRNA, and receptor/ligand interaction requirements for the FPr protein.

Study of anticipation in Chinese families with schizophrenia

The anticipation phenomenon is an important aspect in several genetic disorders in which the age at onset (AAO) decreases and the severity of illness increases in successive generations. This phenomenon has been reported in several schizophrenic family studies, and expanded repeat mutations are implicated. In the present study, we investigate the anticipation phenomenon in Chinese schizophrenic families. We compare the AAO between two generations of 38 unilinear schizophrenic families. Intergenerational comparisons show that the AAO was significantly earlier in the offspring generation (mean AAO, 22.2 years) than that in the parental generation (mean AAO, 31.0 years) (P < 0.001). When only including the offspring generation who married, the AAO difference between the two generations was not significant (28.4 years vs 31.0 years, P = 0.151). Our findings suggest that a selection bias in the parental group might greatly impact the study of anticipation in schizophrenia. Other unavoidable biases associated with these analyses are discussed in the text.

Genetic variants of the serotonin system and weight change during clozapine treatment

Clozapine-induced weight gain may impair health and affect patient compliance. The aim of this study is to investigate the relationship between the genetic variants of the serotonin system and clozapine-induced body weight change (BWC). Ninety-three treatment-resistant schizophrenic patients were weighed monthly for 4 months during clozapine treatment. At the conclusion of treatment, patients had gained an average of 2.4 kg body weight, with BWC ranging from -17.5 to +12.9 kg. The levels of the serotonin transporter variants, serotonin 2A, serotonin 2C and serotonin 6, demonstrated no statistically significant relationship to BWC. Patients with a lower initial body mass index demonstrated a greater weight gain associated with clozapine treatment. Further exploration of the neurotransmitters implicated in the antipsychotic-induced BWC is important in order to reduce the morbidity and noncompliance associated with weight gain.

The clinical applications of Mini-Mental State Examination in geropsychiatric inpatients

OBJECTIVE

This study investigated the association between Mini-Mental State Examination (MMSE) scores and diagnosis, computerized tomographic scans or electroencephalogram findings in geropsychiatric inpatients (age > or = 65).

METHOD

We analyzed the MMSE records of patients sixty-five and older who had been hospitalized in our psychiatric ward during a nine-year period. Case data were collected by review of chart records.

RESULTS

In these patients, MMSE scores were significantly different among the seven diagnostic groups included. Demented patients had the lowest MMSE scores. Patients who had abnormal findings on computerized tomographic scans or electroencephalogram had lower MMSE than patients with normal findings.

CONCLUSION

Our findings suggest that the MMSE is a useful screening instrument for organicity in the geropsychiatric inpatients. However, because of the lower average MMSE score in geropsychiatric inpatients, the optimal cut-offpoint of MMSE for dementia should be lower than those used in other populations.

Association study of apolipoprotein E epsilon4 with clinical phenotype and clozapine response in schizophrenia

Schizophrenic patients with the apolipoprotein E (APOE = gene; apoE = protein) epsilon4 allele exhibited lower psychosis scores than patients without the epsilon4 allele in previous reports. The present study tested the hypothesis that the APOE epsilon4 allele confers association with the clinical manifestations of schizophrenia or clozapine response. A total of 95 schizophrenic patients who were treatment resistant were included in the study. The results demonstrated that the presence of the APOE epsilon4 allele did not influence the response to clozapine in schizophrenic patients, neither was the baseline psychopathology related to the APOE epsilon4 allele. Given the multiple functions of the apoE protein in the brain, further study of the influence of APOE on CNS medication response is needed.

Repetitive phenomena in dementia

OBJECTIVE

Both repetitive talk and behaviors (repetitive phenomena) are common in demented patients and are bothersome to their caregivers and families. The purpose of this preliminary report was to explore these repetitive phenomena in demented patients admitted to a geropsychiatric ward.

METHOD

The sample population consisted of 141 demented patients. Patients' caregivers were asked if patients had presented a repetitive fixed pattern of physical action or talk since the onset of dementia.

RESULTS

Of the 141 demented patients included in the study, seventy-nine had repetitive phenomena. Patients with these phenomena had various presentations and developed them in the early stage of dementia.

CONCLUSIONS

Repetitive phenomena are widespread in dementia, especially for older patients, and may be an early sign of dementia. The characteristics of repetitive phenomena and some likely underlying mechanisms are discussed.

The correlations between the difficult temperament and subjective psychiatric symptoms in Chinese early adolescents

This study was designed to assess the intercorrelations between difficult temperament factors and self-rating psychiatric symptoms in Chinese early adolescents. The study subjects completed the Chinese Adolescent Temperament Self-Rating Questionnaire and Brief Psychiatric Symptom Rating Scale. Results revealed that the group of subjects with two or more difficult temperament factors showed significantly higher scores in some of self-rating psychiatric symptoms. In addition to difficult temperament factors, low score of task orientation and tactile threshold also appeared to be risk factors for self perceived psychiatric symptoms in the Chinese adolescents.