Hyperphosphorylation of protein Tau in hippocampus may cause cognitive dysfunction of propofol-anesthetized rats.

OBJECTIVE: We aimed to explore the effect of hyperphosphorylation of Tau on cognitive function of propofol-anesthetized rats. MATERIALS AND METHODS: Thirty 2-month-old male Wistar rats weighing 180-220 g were randomly divided into 3 groups (n=10): group of treating with saline (C group), group of treating with propofol for 1 hour (P1) and 24 h (P24 group). The cognitive function of rats was tested by Morris water maze before and 1 h or 24 h after drug administration. The rats were then sacrificed. The protein and mRNA expression levels of GSK-3ß, total and phosphorylated Tau, cyclin D1, p27kip1 and c-caspase 3 in hippocampus were determined by Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR), respectively. RESULTS: Compared with group C, the incubation period of P1 group and P24 group was prolonged, and the target quadrant retention time was shortened (p<0.05). There was no statistical difference between P1 and P24 group (p>0.05). Immunohistochemistry showed that compared with group C, p-Tau in hippocampus of P1 group and P24 group was highly expressed, with statistical difference (p<0.05). Western blot and RT-PCR showed that protein and mRNA expressions of GSK-3ß, phosphorylated Tau, cyclin D1 and c-caspase 3 in hippocampus of P1 and P24 groups were up-regulated (p<0.05). CONCLUSIONS: Propofol-induced cognitive dysfunction in rats may be related to the hyperphosphorylation of Tau that causes neuronal cells to re-enter the cell cycle, thus leading to apoptosis.

Impaired DNA damage response in cells expressing an exon 11-deleted murine Brca1 variant that localizes to nuclear foci.

Both human and mouse cells express an alternatively spliced variant of BRCA1, BRCA1-Delta11, which lacks exon 11 in its entirety, including putative nuclear localization signals. Consistent with this, BRCA1-Delta11 has been reported to reside in the cytoplasm, a localization that would ostensibly preclude it from playing a role in the nuclear processes in which its full-length counterpart has been implicated. Nevertheless, the finding that murine embryos bearing homozygous deletions of exon 11 survive longer than embryos that are homozygous for Brca1 null alleles suggests that exon 11-deleted isoforms may perform at least some of the functions of Brca1. We have analyzed both the full-length and the exon 11-deleted isoforms of the murine Brca1 protein. Our results demonstrate that full-length murine Brca1 is identical to human BRCA1 with respect to its cell cycle regulation, DNA damage-induced phosphorylation, nuclear localization, and association with Rad51. Surprisingly, we show that endogenous Brca1-Delta11 localizes to discrete nuclear foci indistinguishable from those found in wild-type cells, despite the fact that Brca1-Delta11 lacks previously defined nuclear localization signals. However, we further show that DNA damage-induced phosphorylation of Brca1-Delta11 is significantly reduced compared to full-length Brca1, and that gamma irradiation-induced Rad51 focus formation is impaired in cells in which only Brca1-Delta11 is expressed. Our results suggest that the increased viability of embryos bearing homozygous deletions of exon 11 may be due to expression of Brca1-Delta11 and suggest an explanation for the genomic instability that accompanies the loss of full-length Brca1.

Psychiatric co-morbidity among male heroin addicts: differences between hospital and incarcerated subjects in Taiwan.

AIMS: To examine the differences in psychiatric co-morbidity between hospital and incarcerated groups of heroin addicts in Taiwan. DESIGN: Life-time prevalence of DSM-III-R-based coexisting psychiatric disorders, including personality disorders, were surveyed. SETTINGS: A psychiatric hospital and two prisons. PARTICIPANTS: Two hundred and sixty heroin users who were incarcerated in prisons, and 47 heroin users who voluntarily sought help in a psychiatric hospital were interviewed by board-certified psychiatrists. MEASUREMENTS: Using two psychometric instruments, the Psychiatric Diagnostic Assessment (PDA) and the Structured Interview for DSM-III-R Personality Disorders (SIPD-R), psychiatric co-morbidity was assessed. FINDINGS: Different life-time rates of coexisting psychiatric disorders among heroin addicts in different settings were found: 83% of hospital subjects and 66% of incarcerated subjects were diagnosed as having at least one coexisting axis I or II disorder. The most prevalent coexisting DSM-III-R defined axis I disorders were additional substance use disorders (alcohol and methamphetamine), while the axis II disorder was antisocial personality disorder. The hospital group had a significantly higher prevalence rate of mood disorder (p < 0.001), paranoid personality disorder (p < 0.05) and antisocial personality disorder (p < 0.001) than the incarcerated group. CONCLUSIONS: We suggest that heroin addicts with coexisting psychiatric disorders receive relevant psychiatric treatment. Those with personality disorders, especially the antisocial type, should be considered for specialized therapeutic community programmes instead of incarceration.

Characteristics of mentally retarded criminal offenders in Northern Taiwan.

The characteristics and criminal behavior in mentally retarded individuals remain largely unstudied. This retrospective study sought to establish a set of reference of criminal behavior characteristics in an ethnic Chinese mentally retarded group. Data were collected from forensic psychiatric evaluation of 32 mentally retarded offenders. Of the 32 offenders, only four (12.5%) cases were female. Mean age at the time of the offenses was 31. By IQ testing, 23 (71.9%) of the group fell into the mild mental retardation range, seven (21.9%) into the moderate mental retardation range, and two (6.2%) into the severe mental retardation range. Nineteen (59.3%) of the group also suffered from additional mental disorder. Eight (25%) had definite neurological deficit. Fourteen (43.8%) were repeat offenders. A total of 24 (75%) of the offenders had committed crimes against property, with 13 having committed petty theft. Furthermore, the pattern of offending shows differences from that of the general population or other mental disorders. The property offenses, especially petty theft and arson, were frequently seen. There was no noteworthy above average frequency of sexual offenses.

A modified mini nutritional assessment without BMI predicts nutritional status of community-living elderly in Taiwan.

OBJECTIVE: The study was to determine whether a modified MNA (Mini Nutritional Assessment) which adopted population-specific anthropometric cut-points but without BMI could maintain its predicting ability in community-living elderly in Taiwan. DESIGN: Purposive sampling. SETTING: Community-living elderly. PARTICIPANTS: Three hundred and one (138 male and 163 female) > 65-year-old outpatients seeking free annual health examination at an area hospital in central Taiwan. MEASUREMENTS: A structured questionnaire elicited personal data, lifestyle information and answers to the MNA. Laboratory results from health checkup provided the needed biochemical data. Each subject's nutritional status was assessed with the MNA in three versions: the original, the MNA-TI (with population-specific cut-points), and the MNA-TII (further eliminated the BMI question and redistributed its score to the MAC and CC questions). RESULTS: All three versions identified the same 0.7% elderly malnourished. The proportions predicted at risk of malnutrition were 16.6, 12.0 and 10% according to the original, MNA-TI and MNA-TII, respectively. Friedman Test and post hoc analysis indicated that the pattern predicted by the original MNA was different from that predicted by the two modified versions whereas the patterns predicted by the two modified versions were not different from each other. CONCLUSION: Adoption of population-specific anthropometric cut-points improves the predicting ability of the MNA in Taiwanese elderly, and the improved functionality is maintained in a version without BMI (but with adjusted MAC and CC scores). A MNA without BMI has greater applicability and can enhance professional efficiency of healthcare workers.

Paternal inheritance of chloroplast DNA in interspecific hybrids in the genus Larrea (Zygophyllaceae).

The mode of chloroplast DNA (cpDNA) inheritance was investigated in the genus Larrea (Zygophyllaceae) by polymerase chain reaction (PCR) amplification of cpDNA fragments using three pairs of chloroplast universal primers. A total of 20 F(1)s from interspecific crosses among five different taxa in the section Bifolium was examined. Twelve F(1)s were from six crosses between L. cuneifolia (4x) and L. divaricata (2x) (Peru or Argentina) or L. tridentata (2x or 4x). Eight F(1)s were from two sets of reciprocal crosses between L. divaricata (2x) (Argentina) and L. tridentata (2x). Length polymorphism was observed in all three regions of cpDNA that separated L. cuneifolia parents from L. divaricata and L. tridentata parents and in one of the three cpDNA regions that differentiated L. divaricata (Argentina) parents from L. tridentata (2x) parents. In each case, it was the paternal cpDNA marker that appeared in the F(1) individuals. This was further confirmed by restriction fragment length polymorphism (RFLP) analysis of the amplified cpDNA fragments. Larrea may be the fifth genus reported in angiosperms with a paternal bias in cpDNA transmission. Possible mechanisms that may result in paternal cpDNA inheritance were briefly reviewed. Based on the observed uniparental paternal inheritance of cpDNA, restriction analysis of the three cpDNA regions and previous cytogenetic studies, L. divaricata was probably the maternal progenitor of L. cuneifolia.