Gentic risk for schizophrenia, birthweight, and cerebral ventricular enlargement.

Recent work by Silverton, Finello, Mednick, and F. Schulsinger (1985) indicates a relation between low birthweight and cerebral ventricular enlargement, as assessed in adulthood, in a group of subjects at risk for schizophrenia. In the present study, we examined the role of low birthweight in ventricular enlargement and tested the hypothesis that low birth weight interacts with a genetic predisposition for schizophrenia in its association with enlarged ventricles. This study reports on 34 subjects of the Danish high-risk-for-schizophrenia prospective study. Birthweight, paternal schizophrenia spectrum disorder (PSSD), and an interaction term for these two variables were analyzed in a regression with ventricle-to-brain ratio (VBR) as the dependent variable. As in Silverton et al. (1985), birthweight significantly contributed to the variance in VBR. Although PSSD did not significantly contribute to the variance in VBR, there was a significant interaction effect of birthweight and PSSD on VBR. Results were discussed in terms of a diathesis-stress model of schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Metal release and excretion from cementless titanium alloy total knee replacements

Concentrations of titanium, aluminum, and vanadium were measured in the serum and urine of patients with titanium alloy cementless primary total knee arthroplasty components. Patients were categorized in one of five groups. In Group 1, the patellar and tibial articulating surfaces were made of carbon fiber reinforced ultrahigh molecular weight polyethylene. In Group 2, the patellar and tibial surfaces were made of ultrahigh molecular weight polyethylene. In Group 3, the femoral titanium alloy articulating surface was nitrogen ion implanted with ultrahigh molecular weight polyethylene patellar and tibial articulating surfaces. Patients in Group 4 had failed patellar components, and Group 5 was comprised of age and gender matched control subjects without implants. Serum concentrations of titanium were approximately 50 times greater in patients with failed patellar components (Group 4) and approximately 10 times greater in patients with carbon fiber reinforced polyethylene bearing surfaces (Group 1) when compared with Groups 2 and 3 and the control subjects (Group 5). For aluminum and vanadium, no detectable differences were observed among any of the groups. In addition, analysis of 24-hour urine samples showed no significant differences in titanium, aluminum, or vanadium concentrations among any of the groups. Elevated serum titanium levels may serve as a marker of patellar component failure or accelerated femoral component wear in total knee replacements with titanium alloy bearings. The toxicologic ramifications of these findings are unknown.     

Low birth weight and ventricular enlargement in a high-risk sample.

Studied the relation between adult ventricle size and perinatal complications and birth weight using Ss from a Danish high-risk sample previously studied by 2 of the present authors (1965) in a longitudinal study of children and subsequently diagnosed in a study by F. Endicott and R. Spitzer (1972). Of the 58 28–37 yr olds available for the present study, 15 had been diagnosed as schizophrenic, 18 as borderline, and 25 as having no mental illness. 10 schizophrenics, 10 borderlines, and 14 normals were given computerized tomography scans. Results show ventricular enlargement was significantly negatively related to length and weight at birth and to midwife ratings of neonate prematurity. A lack of association was found between ventricle brain ration (VBR) and composite complication score. Results suggest that enlarged ventricles might be associated with insults occurring in utero. The possibility that a fetal viral infection caused CNS system damage and consequent atrophy as measured by VBR is hypothesized. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Refined structures of bobwhite quail lysozyme uncomplexed and complexed with the HyHEL-5 Fab fragment

The structure and expression pattern of a human gene located within a homozygously deleted region of a metastatic prostate cancer have been characterized. Multiple cDNA fragments of this gene were isolated by hybrid capture with yeast artificial chromosome clones covering the deletion region. Eleven coding exons spanned 205-220 kb of the 730- to 970-kb deletion. The predicted amino acid sequence was 43% identical to that of an anonymous Caenorhabditis elegans gene and 20% identical to an accessory or regulatory subunit of the oligosaccharyltransferase enzyme complex in Saccharomyces cerevisiae. Hydrophobicity profiles of all three gene products were similar and showed four putative membrane-spanning domains in the molecules' C-terminal halves, suggesting a general conservation of function. The gene was expressed as an approximately 1.5-kb mRNA in most nonlymphoid human cells/tissues including prostate, lung, liver, and colon. Expression was detected in many epithelial tumor cell lines, but was undetectable by Northern blot or RT-PCR in 14 of 15 colorectal, 1 of 8 lung, and 1 of 4 liver cancer cell lines. Lack of expression in tumor cell lines was highly correlated with hypermethylation of a CpG island located at the gene's 5' end. These findings form a basis for further work on this candidate tumor suppressor gene.     

Implant stability in revision total hip arthroplasty: allograft bone packing following extended proximal femoral osteotomy

One method of revising the femoral component in revision total hip arthroplasty in the presence of compromised femoral bone stock is to pack the upper femur with particulate allograft and then to cement the femoral component into the allograft bed. This technique is being used clinically with encouraging results. Additionally, surgical exposure of the femoral canal during revision total hip arthroplasty can be greatly improved with an extended trochanteric osteotomy, which is subsequently repaired with wires or cables. To assess the feasibility of performing the allograft bone packing technique following an extended trochanteric osteotomy, the stability of this construct in a cadaver model was measured, using micromotion sensing instruments and loads applied on a materials testing machine. The stability of the cemented allograft impaction construct following extended trochanteric osteotomy was comparable to the stability of the control construct, which consisted of a similar impacted allograft construct without osteotomy. The stability of the osteotomized side was comparable to that of the control side. It is concluded that the initial in vitro stability of the allograft impaction technique following extended proximal femoral osteotomy is adequate to justify experimental in vivo use.