Hippocampal volume in borderline personality disorder with and without comorbid posttraumatic stress disorder: a meta-analysis.

BACKGROUND: Several studies have found a reduction in hippocampal volume in borderline personality disorder (BPD) patients. METHODS: In order to investigate the degree to which comorbid posttraumatic stress disorder (PTSD) could account for reduction in hippocampal volume in these patients, we conducted a systematic review and meta-analysis of studies that compared hippocampal volume in BPD patients with and without PTSD relative to healthy controls. RESULTS: Seven articles, involving 124 patients and 147 controls, were included. We found a statistically significant reduction for the left and right hippocampus. Data from the four studies that discriminated BPD patients with and without PTSD indicate that hippocampal volumes were reduced bilaterally in BPD patients with PTSD, relative to healthy controls, but that results were mixed for BPD patients without PTSD, relative to healthy controls. CONCLUSIONS: Results from this meta-analysis suggest that hippocampal volumes are reduced in patients with BPD, relative to healthy controls, but particularly in cases in which patients are diagnosed with comorbid PTSD.

Risperidone versus haloperidol in the treatment of schizophrenia: a meta-analysis comparing their efficacy and safety.

The aim of this study was to compare the short-term clinical efficacy and safety of risperidone with haloperidol and placebo. A meta-analysis of seven published randomized double-blind controlled trials was carried out. Study quality was assessed. The proportion of patients failing to reach at least 20% improvement on the positive and negative syndrome scale (PANSS) or brief psychiatric rating scale (BPRS), the proportion of patients discontinuing treatment because of adverse effects and the number of patients who needed antiparkinsonian medication were abstracted for use as outcome measures. Treatment failure was present in 50% of risperidone-treated patients compared to 66% in those treated with haloperidol and 83% in those treated with placebo. It would be necessary to treat 11 patients with risperidone to prevent one treatment failure in those patients treated with haloperidol (Odds ratio (OR) = 0.74, 95% CI of 0.58-0.94, P = 0.02). Pooling of the three multicentre trials which included placebo as a treatment arm, showed that one in three patients treated with risperidone 4-16 mg/day (OR = 0.22, 95% CI of 0.13-0.39, P < 0.00001) and one in six treated with haloperidol 10-20 mg/day. (OR = 0.44, 95% CI of 0.22-0.84, P = 0.02) would derive significant benefit. Moreover, there was a highly significant greater need for anticholinergic medication due to extrapyramidal symptoms (EPS) in the haloperidol-treated patients compared to risperidone (OR = 0.54, 95% CI of 0.42-0.70, P < 0.00001). In conclusion, risperidone seems to be more effective and causes less EPS than haloperidol, as suggested by the significantly lower requirement for antiparkinsonian medication.

Haloperidol blood levels and clinical outcome: a meta-analysis of studies relevant to testing the therapeutic window hypothesis.

Haloperidol, the most studied antipsychotic drug, is the only one about which reliable statements on the relationship between blood levels and clinical outcome can be made. A systematic overview was undertaken to determine whether there was an optimum blood concentration range for clinical efficacy. Eighteen published studies which provided individual patient data in tables or graphs were reviewed. Clinical benefits tended to decline when the haloperidol blood concentration was increased above 26 ng/ml. Our data support the existence of a therapeutic window between 4 and 26 ng/ml for haloperidol in the treatment of schizophrenic, schizoaffective and schizophreniform disorders.

Is there a relationship between antipsychotic blood levels and their clinical efficacy? An analysis of studies design and methodology.

There are now more than 50 studies concerning neuroleptic blood levels and clinical outcome relationships. Haloperidol, the most studied, is the only antipsychotic permitting some conclusions. A number of authors suggest that the striking lack of agreement between different studies results from heterogeneity of their quality. Here, we have used a scoring system for assessing the quality of those studies. According to this system, none (0/14) of the studies having a score < 0.60 was able to show a therapeutic window, as compared to 53% (10/19) of those having a score > or = 0.60 (p = 0.002, Fisher exact test). Also, the studies able to identify the presence of a therapeutic window during haloperidol treatment were those having sample size > 20 (p = 0.06) and those whose patients were treated with fixed doses (p = 0.02). The diagnosis of schizophrenia in the studies seems not to be an exclusive condition, as compared with those also including schizophreniform and schizoaffective disorders (p = 0.12). Our qualitative analysis of haloperidol blood level publications seem to indicate that an upper limit may exist for haloperidol efficacy; values above this limit seem not to provide any supplementary clinical improvement and may even reduce therapeutic effect.

Homologous DNA targeting with RecA protein-coated short DNA probes and electron microscope mapping on linear duplex molecules.

We demonstrate that RecA protein-coated, short single-stranded DNA probes paired with a specific homologous DNA sequence in a linear duplex target molecule and accurately targeted the selected DNA sequence. RecA protein-coated complementary ssDNA probes were reacted with linear duplexes, and the homologously paired molecules were observed by electron microscopy. The sites of interaction between the RecA protein-coated DNA probes and the uncoated duplex DNA targets were directly visible on individual target DNA molecules by high-resolution darkfield electron microscopy, without chemical fixation or sample shadowing. The efficiency and specificity of pairing were verified with 446 and 222 base single-stranded DNA probes that shared no homology with one another, and several linear duplex target DNAs with their respective probe homology sites at different locations with respect to the ends of the double-stranded DNA molecules. Measurements of the position of RecA protein-coated probes paired to individual target molecules, observed at high magnification, showed that DNA probes specifically paired at their corresponding homologous target sequences. This RecA protein-mediated DNA mapping method allows homologous sequence positioning and gene mapping on individual double-stranded DNA molecules. Targeting reactions in which two different probe/target sites were 900 bases apart on a single duplex target molecule allowed both sites to be mapped in the same targeting reaction; although targets displaying both probes simultaneously were seen much less frequently than expected. The possible torsional or mechanistic constraints related to these reactions are briefly discussed.

Targeting in linear DNA duplexes with two complementary probe strands for hybrid stability.

A new in vitro hybridization reaction targets two short complementary RecA protein-coated DNA probes to homologous sequences at any position in a linear duplex DNA molecule. Stable hybrids are obtained after RecA protein removal when both complementary probe strands are present in a four-stranded hybrid, but not when one probe strand is present in a three-stranded hybrid. In four-stranded hybrids with one probe strand biotinylated and the other radiolabelled, the deproteinized hybrids can be isolated and detected by affinity capture on streptavidin-coated magnetic beads. RecA-mediated targeting of complementary biotinylated DNA probe strands allows the affinity capture of 48.5-kilobase duplex lambda genomic DNA. These reactions provide a means of isolating any desired duplex gene or chromosomal DNA fragment.

Cytoplasmic microinjection of immunoglobulin Gs recognizing RNA helices inhibits human cell growth.

We report here that nucleolar and cytoplasmic RNA in mammalian cells is recognized specifically by both experimentally induced monoclonal IgG unique for left-handed Z-RNA and by autoimmune mouse monoclonal IgG specific for ribosomal RNA. Nucleolar Z-RNA synthesis, like nucleolar ribosomal RNA synthesis, is inhibited by actinomycin D treatment and dimethylsulfoxide-induced differentiation. Immune anti-Z-RNA IgGs microinjected into living nuclei bind nucleolar RNA, and these complexes appear to be removed from the nucleus within minutes. Cytoplasmically microinjected monoclonal or polyclonal anti-Z-RNA IgGs specifically bind cytoplasmic RNA and inhibit cell multiplication. Microinjection of antibodies directed against double-stranded RNAs. Elevated ionic conditions, which in energy-minimized models can cause the walls of the groove in Z-RNA (but not Z-DNA) to approach each other and close, also prevent antibody binding to specific synthetic or cellular Z-RNA determinants. Our antibodies binding unique Z-RNA structures probably recognize antigens determined by the exposed 2'-OH ribose sugar-phosphate groups.

Genetic and physical analysis of the M26 recombination hotspot of Schizosaccharomyces pombe.

The ade6-M26 mutation of Schizosaccharomyces pombe has previously been reported to stimulate ade6 intragenic meiotic recombination. We report here that the ade6-M26 mutation is a single G----T nucleotide change, that M26 stimulated recombination within ade6 but not at other distinct loci, and that M26 stimulated meiotic but not mitotic recombination. In addition, M26 stimulated recombination within ade6 when M26 is homozygous; this result demonstrates that a base-pair mismatch at the M26 site was not required for the stimulation. These results are consistent with the ade6-M26 mutation creating a meiotic recombination initiation site.

In vivo homologous recombination intermediates of yeast mitochondrial DNA analyzed by electron microscopy.

To study the structure of in vivo mitochondrial DNA recombination intermediates in Saccharomyces cerevisiae, we used a deletion mutant of the wild type mitochondrial genome. The mtDNA of this petite is composed of a direct tandem repetition of an approximately 4,600 bp monomer repeat unit with a unique HhaI restriction enzyme site per repeat. The structure of native mtDNA isolated from log phase cells, and mtDNA crosslinked in vivo with trioxsalen plus UVA irradiation, was studied by electron microscopy. Both populations contained crossed strand "Holliday" type recombination intermediates. Digestion of both non-crosslinked and crosslinked mtDNA with the enzyme HhaI released X and H shaped structures composed of two monomers. Electron microscopic analysis revealed that these structures had pairs of equal length arms as required for homologous recombination intermediates and that junctions could occur at points along the entire monomer length. The percentage of recombining monomers in both non-crosslinked and trioxsalen crosslinked mtDNA was calculated by quantitative analysis of all the structures present in an HhaI digest. The relationship between these values and the apparent dispersive replication of mtDNA in density-shift experiments and mtDNA fragility during isolation is discussed.

A and alpha supernatant pretreatment of Saccharomyces cerevisiae cells affects both the kinetics and efficiency of mating.

The effects of culture supernatant treatment on subsequent matings between pretreated a and alpha Saccharomyces cerevisiae cells were studied. For each experiment, pairs of a and alpha [rho+] or [rho- rho0] cells in the logarithmic growth phase in defined minimal medium were pretreated for a total of 15 min (by exchanging their cell-free supernatants or by mixing samples of a and alpha cell cultures) and then mated in defined minimal (YNB) or enriched (YEP) liquid medium. All pretreated cells, regardless of treatment procedure, initiated cell fusion 15 to 35 min faster than did their nontreated counterparts. In all cases, pretreated cells mated 8 to 20% more efficiently than did nonpretreated ones. Regardless of the strains, the hierarchy of mating efficiency was always treated YEP greater than untreated YEP greater than treated YNB greater than untreated YNB. The cell fusion kinetics in alpha [rho+] X a [rho-] crosses were most affected by pretreatment (delta 30 to 35 min), whereas [rho+] X [rho+] crosses were least affected (delta 15 min). These results are discussed in relation to the functions known for a and alpha pheromones. The successful pretreatment regimes were used to design new rapid and efficient techniques for mating YNB-grown log-phase cells in either YNB or YEP liquid media. These techniques can be used for small- or large-scale mating, and because of their inherent media flexibility, they have many potential applications to future studies on mating-specific or intrazygotic phenomena.

Effects of the kar gene on cytoplasmic mixing and mitochondrial genome suppressiveness, and consequences for cytoduction of petite DNA in Saccharomyces cerevisiae.

During a series of cytoduction experiments to transfer Saccharomyces cerevisiae mitochondrial genomes from one nuclear background to another, using the karl-1 nuclear fusion mutation, one of the five petite genomes used proved difficult to transfer. This genome, ϱ(-) F13, was highly suppressive (90%) in its original nuclear background. Molecular and genetic studies on the putative karl-1 ϱ(-)F13 cytoductant were done to discover the nature of this difficulty. They showed that while the ϱ(-)F13 was maintained in a karl-l background, zygotes from a mating with a ϱ(0) strain showed poor cytoplasmic mixing and therefore inefficient ϱ(-)F 13 DNA transfer into first zygotic buds. This also caused a reduction of ϱ(-)F13 suppressiveness to 20-30% in crosses with different ϱ(+) strains. The effect was genome specific since another highly suppressive petite in the karl-l background did not show suppressiveness reduction when crossed to ϱ(+). The nature of suppressiveness modulation is discussed. Since the ϱ(-)F13 genome was eventually transferred using a modification of the original scheme, the problems were not caused by the inability of the acceptor nuclear background to maintain the ϱ(-)F13 genome.

Cytoplasmic mixing in Saccharomyces cerevisiae: Studies on a grande X neutral petite mating and implications for the mechanism of neutrality.

We have studied zygotic cytoplasmic mixing in two neutral petite by grande matings. Cytoplasmic mixing in zygotes and zygotic buds was followed histochemically and genetically. Both techniques showed that in most zygotes rapid cytoplasmic mixing occurred after early zygote formation and before first bud completion. The progeny mitochondrial genotypes produced from each cross were compatible with a model assuming random segregation of petite and grande inputs between the zygote and its first bud.While both crosses produced only grande zygotic colonies and grande diploid progeny when assayed by classical genetic methods, a class of events producing petite zygotes, retaining petite mitochondrial DNA, with grande first diploid buds was discovered. The results show that the expression of neutrality in our strains requires efficient cytoplasmic mixing during zygote maturation. The results suggest that the expression of mitochondrial genome neutrality requires competition or interaction between petite and grande parental mitochondrial DNA molecules. The possible nature of these phenomena is discussed.

Nuclear and mitochondrial deoxyribonucleic acid replication during mitosis in Saccharomyces cerevisiae.

To study nuclear and mitochondrial deoxyribonucleic acid (DNA) synthesis during the cell cycle, a 15N-labeled log-phase population of Saccharomyces cervisiae was shifted to 14N medium. After one-half generation, the cells were centrifuged on a sorbitol gradient in a zonal rotor to fractionate the population according to cell size and age into fractions representing the yeast cell cycle. DNA samples isolated from the zonal rotor cell samples were centrifuged to equilibrium in CsC1 in an analytical ultracentrifuge to separate the nuclear and mitochondrial DNA components. The amount of 14N incorporated into each 15N-labeled DNA species was measured. The extent of nuclear DNA replication per sample was obtained by measuring the amount of hybrid DNA. The percentage of hybrid nuclear DNA increased from 6 to 68% and then decreased to 44% during the cell cycle. Upon ultracentrifugation, mitochondrial DNA banded as a unimodal peak in all zonal rotor samples. Mitochondrial DNA replication could be ascertained only by the 14N level in each mitochondrial peak and not, as with nuclear DNA, by hybrid DNA level. In contrast to the nuclear incorporation pattern, the 14N percentage in mitochondrial DNA remained effectively constant during the cell cycle. Comparison of the data to theoretical distributions showed that nuclear DNA was replicated discontinuously during the cell cycle, whereas mitochondrial DNA was replicated continuously throughout the entire mitotic cycle.

Synchronous mating in yeast.

Homogeneous a and alpha unbudded yeast cells in logarithmic phase, grown in supplemented minimal medium and isolated by zonal gradient centrifugation, are used for mating. When these cells are resuspended in aerated defined medium, highly synchronous mating rapidly occurs. Within 20 min of incubation at 30 degrees early sexual pairing is evident; extensive agglutination is observed by 60 min, and cell fusion and bud initiation in zygotes occurs after 60-140 min. Sorbitol gradient fractionation of mating mixtures taken at various times during incubation allows the isolation of zygotes or unmated cells. Zygote preparations 90-95% purified are obtained in quantities suitable for genetic and biochemical analysis. The mating procedure is predictable and reproducible.