Matrilineal inheritance of complex I dysfunction in a multigenerational Parkinson's disease family

Recent data suggesting complex I dysfunction in Parkinson's disease (PD) arises from mitochondrial DNA (mtDNA) mutation does not conclusively answer whether the responsible genetic lesion is inherited (primary) or somatic (secondary). To address this question, we identified a family in which multiple members over three generations are affected with PD through exclusively maternal lines. Cytoplasmic hybrids (cybrids) were created for 15 family members over two generations by transferring each individual's mtDNA to mtDNA-depleted human neuroblastoma cells. Eight of the 15 cybrid lines contained mtDNA obtained from maternally descended family members and seven contained mtDNA from paternally descended family members. After 6 weeks of culture, cybrid cell lines were assayed for complex I activity and oxidative stress, and mitochondrial morphology was analyzed by electron microscopy. Compared with the cybrid lines containing mtDNA from paternal descendants, cybrid lines containing mtDNA from maternal descendants had lower complex I activity, increased reactive oxygen species production, increased radical scavenging enzyme activities, and more abnormal mitochondrial morphologic features. These findings were present in cybrid lines containing mtDNA from maternal descendants with PD as well as in currently asymptomatic young maternal descendants, and support a precedent for inherited mtDNA mutation in some persons with PD.     

The effect of stimulus range on perceived contrast: Evidence for contrast gain control.

Investigated whether the stimulus range affected the perceived contrast of vertical gratings whose spatial frequencies were either 1 or 4 cycles/deg to determine if adjustive processes apply to the contrast sensitivity of spatial frequency channels in a vision task. Nine Ss judged the perceived contrasts of 1 and 4 cycle/deg gratings intermixed within a session. Four different conditions were created by combining either a set of low-contrast or high-contrast gratings at 1 frequency with a broad range of contrasts at the other frequency. When the broad-range set was at 1 cycle/deg, contrast-matches across spatial frequencies were unaffected by changing the range of the 4-cycle/deg gratings. When the broad-range set was 4 cycles/deg, contrast matches were changed by changing the range of the 1 cycle/deg gratings. This asymmetry in the range effect was shown to be consistent with the characteristics of the 2 channels' receptive-field profiles. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Customer satisfaction and self-reported treatment outcomes among psychiatric inpatients

OBJECTIVE: Relationships among different dimensions of patient satisfaction and selected demographic, clinical, and outcome variables were explored in a sample of severely ill people receiving inpatient psychiatric services. METHOD: The sample consisted of 81 patients admitted to and discharged from an inpatient psychiatric unit at a midwestern Veterans Affairs medical center. Stepwise multiple regression was used to examine the relationship between patient satisfaction and self-reported changes in quality of life, symptomatology, and level of functioning as measured by the Treatment Outcome Profile. Other variables such as diagnosis, length of stay, employment, living situation, and prior psychiatric and substance abuse treatment were also considered. A subsample of the most satisfied and dissatisfied patients was chosen to further explore variables contributing to satisfaction with services. RESULTS: Patient satisfaction was related to initial level of functioning, certain diagnoses, and treatment gains. Clinicians were highly accurate in identifying patients who were satisfied, based on blind chart reviews. CONCLUSIONS: This study underscores the significant relationships between patient satisfaction, psychiatric diagnosis, and other outcome measures, and argues for the validity and utility of patient satisfaction measures in assessing the efficacy of inpatient care.     

Sexual conflict and speciation

We review the significance of two forms of sexual conflict (different evolutionary interests of the two sexes) for genetic differentiation of populations and the evolution of reproductive isolation. Conflicting selection on the alleles at a single locus can occur in males and females if the sexes have different optima for a trait, and there are pleiotropic genetic correlations between the sexes for it. There will then be selection for sex limitation and hence sexual dimorphism. This sex limitation could break down in hybrids and reduce their fitness. Pleiotropic genetic correlations between the sexes could also affect the likelihood of mating in interpopulation encounters. Conflict can also occur between (sex-limited) loci that determine behaviour in males and those that determine behaviour in females. Reproductive isolation may occur by rapid coevolution of male trait and female mating preference. This would tend to generate assortative mating on secondary contact, hence promoting speciation. Sexual conflict resulting from sensory exploitation, polyspermy and the cost of mating could result in high levels of interpopulation mating. If females evolve resistance to make pre- and postmating manipulation, males from one population could be more successful with females from the other, because females would have evolved resistance to their own (but not to the allopatric) males. Between-locus sexual conflict could also occur as a result of conflict between males and females of different populations over the production of unfit hybrids. We develop models which show that females are in general selected to resist such matings and males to persist, and this could have a bearing on both the initial level of interpopulation matings and the likelihood that reinforcement will occur. In effect, selection on males usually acts to promote gene flow and to restrict premating isolation, whereas selection on females usually acts in the reverse direction. We review theoretical models relevant to resolution of this conflict. The winning role depends on a balance between the 'value of winning' and 'power' (relating to contest or armament costs): the winning role is likely to correlate with high value of winning and low costs. Sperm-ovum (or sperm-female tract) conflicts (and their plant parallels) are likely to obey the same principles. Males may typically have higher values of winning, but it is difficult to quantify 'power', and females may often be able to resist mating more cheaply than males can force it. We tentatively predict that sexual conflict will typically result in a higher rate of speciation in 'female-win' clades, that females will be responsible for premating isolation through reinforcement, and that 'female-win' populations will be less genetically diverse.     

An on-line microcomputing system for the acquisition and processing of data from a fourier spectrometer

A microcomputing system has been developed to provide on-line data acquisition and analysis for a Fourier transform spectrometer, and the interface between the spectrometer and the microcomputer is described in detail. The system has been equipped with software which includes a fast Fourier transform programme for use in either conventional or dispersive Fourier transform spectroscopy, and programmes for calculating the optical constants and dielectric functions of solids from complex spectra obtained by dispersive Fourier transform spectroscopy.     

Approximation programming of chemical processes—2: computational difficulties

Part 1 of this series presents successful results in implementing quadratic approximation programming for optimization of processes modelled with Monsanto's FLOWTRAN®³ system. Detailed analysis of the computations indicates that the optimization of the approximate quadratic models provides one of the main computational problems. This paper describes some of these problems and our solutions, and indicates further improvements which should be investigated.     

Effect of pulpmill effluent on dissolved oxygen in a stratified estuary—I. Empirical observations

Pulpmill effluent discharged at the surface in Alberni Inlet is shown to prevent oxygen production in the stratum immediately beneath the halocline by restricting light penetration. This stratum is the source of marine water for entrainment in the halocline and to the upper mixed zone. This situation cannot be remedied by removal of BOD from the pulpmill effluent, rather the staining properties must be diminished or removed.