Serotonin neuronal release from dorsal hippocampus following electrical stimulation of the dorsal and median raphé nuclei in conscious rats

We have studied 5-hydroxytryptamine (5-HT) release in the hippocampal formation following electrical stimulation of the dorsal and median raphé nuclei in the behaving rat. The primary finding in this study is a decrease in neuronal release of serotonin in the dorsal hippocampal formation following electrical stimulation of either the dorsal or median raphé nucleus in conscious rats. At no time did electrical stimulation of either raphé nucleus result in behavioral, including vigilance state, changes. The amount of 5-HT released was found to be frequency dependent with higher frequencies (20 Hz) producing larger decreases in release of 5-HT. However, the pattern of release differs between the two raphé nuclei. Extracellular levels of 5-HT decrease during stimulation of the dorsal raphé, whereas levels decrease only following cessation of stimulation of the median raphé nucleus. This may relate to the patterns of innervation of the dorsal hippocampal formation by these two midbrain raphé nuclei and also may reflect an inhibition of median raphé cell firing during stimulation of the dorsal raphé. Electrical stimulation of the dorsal raphé in anesthetized animals resulted in an enhanced release of 5-HT. The suppression of 5-HT release in the dorsal hippocampal formation in behaving animals was long-lasting (over 2 h), suggesting that the control mechanisms that regulate 5-HT release operate over a long time-course. This difference in release between non-anesthetized and anesthetized animals may relate to anesthesia blocking long- and/or short-loop serotonin recurrent axonal collaterals negatively feeding back onto 5-HT1A and 5-HT1D somatodendritic autoreceptors on raphé neurons. Further, the anesthetized animal has diminished monoaminergic "gating" influences on the hippocampal formation, whereas the behaving animal is more complex with behavioral (vigilance) states associated with different patterns of gating of information flow through the hippocampal formation.

Combined liver-kidney transplantation in methylmalonic acidemia

A 13-year-old boy with non-B12-responsive methylmalonic acidemia (MMA) had chronic renal failure. Hemodialysis led to symptomatic and biochemical improvement. He subsequently received a combined liver-kidney transplant. After 16 months of follow-up he has a normal lifestyle and a marked reduction in plasma and urine methylmalonate.

Does 'healing' benefit patients with chronic symptoms? A quasi-randomized trial in general practice

This study was designed to examine the effects of a healer seeing chronically ill patients in a large semirural practice. The 57 patients were allocated alternately either to receive ten weekly healing sessions or to become waiting-list controls. Two weeks after completion of 'healing' 22 (81%) of the 27 study patients thought their symptoms had improved and 15 of these thought they had improved substantially. Study patients scored better than controls on both measures of symptoms (P < 0.05, P < 0.01), on anxiety and depression ratings (P < 0.01, P < 0.05) and on general function measured by the Nottingham Health Profile (P < 0.01). Treatment differences were still evident three months later for one of the measures of symptom change (P < 0.05) and for both anxiety and depression ratings (P < 0.01, P < 0.05). The percentages of natural killer cells (CD16, CD56) did not change greatly in either group. These results suggest that healing may be an effective adjunct for the treatment of chronically ill patients presenting in general practice. They do not distinguish between any specific effects of spiritual healing and non-specific effects such as relaxation; for further investigation, randomized controlled trials will be needed.

The contribution of depression and denial towards understanding the unawareness of symptoms in schizophrenic out-patients

OBJECTIVES

Unawareness of schizophrenic symptoms was postulated to be partially attributable to patients denying symptoms in order to avoid depression.

METHOD

The 24-item version of the Brief Psychiatric Rating Scale (BPRS) was administered to 41 schizophrenic patients (chart diagnoses were validated by a DSM-III-R checklist). The first 14 of these items were then used to gather information about patients' symptomatology from 55 relatives of patients. Unawareness of symptoms was calculated by subtracting patients' total for these 14 items from parents' totals. Two measures of depression were obtained. Subjective depression was the score on the depression item based on patients responses to interview questions, objective depression was the score based on interviews with relatives about their ill family member. Family functioning was also assessed by administering patients' relatives the Camberwell Family Interview and the FACES III.

RESULTS

Hierarchical regression analyses revealed that both subjective and objective measures of depression were significantly related to unawareness; subjective depression was negatively related, and objective depression was positively related. The employed measures of family functioning were unrelated to unawareness of symptomatology.

CONCLUSION

This opposing pattern of subjective and objective depression was interpreted as evidence of the self-deception which characterizes all defence mechanisms including denial.

Initial clinical trial and pharmacokinetics of Thymitaq (AG337) by 10-day continuous infusion in patients with advanced solid tumors

PURPOSE

To establish the maximum tolerated dose (MTD), dose-limiting and other major toxicities and the major pharmacokinetic parameters of a 10-day infusion of the nonclassical antifolate Thymitaq.

METHODS

The drug was given by 10-day infusion via a portable pump. The starting dose was 286 mg/m2 per day with escalation to 572 and 716 mg/m2 per day. Thymitaq in plasma was assayed by a validated isocratic reverse-phase HPLC assay with detection at 273 nm.

RESULTS

The dose of 716 mg/m2 per day x 10 was considered too high as none of three patients completed a 10-day infusion and two of three developed grade IV myelotoxicity. At 572 mg/m2 per day three of four patients completed a 10-day infusion. Dose-limiting myelosuppression was seen in one of four but owing to a high incidence of thrombotic phenomena, no further patients were added.

CONCLUSION

Continuous 10-day infusions of Thymitaq should be limited to low doses until further studies can be done.

Increasing plant productivity in closed environments with inner canopy illumination

Due to the high cost of habitable real estate associated with space travel and colonization, and the ultimate use of plants as the primary method of life support, it is necessary to develop cultivation methods whereby the highest sustainable level of productivity is achieved within the least amount of space. It is well known that in a dense plant canopy, lower leaves become shaded from above and eventually no longer contribute to carbon gain. In fact, they contribute to net respiratory carbon losses. One method of improving biomass production is to introduce light of suitable quantity and quality to the inner canopy, thereby utilizing unused photosynthetic capacity. By coupling microwave-powered lights to 100-mm-diameter glass tubes lined with 3M Optical Lighting Film, light with a spectral quality similar to that of sunlight was delivered to the inner canopy of a developing soybean crop. Results indicated that increases in productivity of 23-87%, as measured by CO2 assimilation, can be achieved in dense plant canopies (LAI approximately 6) when overhead lighting (40O-1200 micromoles m-2 s-1) is supplemented with inner canopy illumination.

The troublesome submerged tooth: a diagnostic dilemma

Facial swelling caused by a periapical abscess is commonly encountered by dental practitioners. It requires prompt treatment, usually by removal of the infective foci and administration of appropriate antibiotics. However, diagnosis can be difficult, and may be complicated by the presence of retained deciduous teeth. This case report demonstrates a diagnostic dilemma and highlights the importance of looking beyond the obvious.

Do you have an IPS (investment policy statement)?

Academic studies have shown that over long-term time periods market timing is responsible for less than two percent of the variance of investment returns; security selection is responsible for less than five percent; while asset allocation policy (the desired mix of stocks and bonds) is responsible for almost 92 percent of the total return variation (see chart). This is yet another reason why it is critical to document the desired asset allocation policy and other guidelines for the portfolio in a written IPS.

The prudent investment process

Are you a CFO, CEO or treasure of your organization? Are you a member of the board of directors or investment or pension committees? If you answered "yes" to these questions, you are likely to be considered a fiduciary of investment assets. This position carries with it prestige, responsibility, and potential personal liability should something go wrong. Of course, liability will most likely occur only if a failure has occurred in carrying out fiduciary responsibilities. But what are those responsibilities? And what is the most appropriate way to manage investment decisions?

Mapping of the locus for autosomal dominant amelogenesis imperfecta (AIH2) to a 4-Mb YAC contig on chromosome 4q11-q21

Amelogenesis imperfecta (AI) is a clinically and genetically heterogeneous group of inherited enamel defects. We recently mapped a locus for autosomal dominant local hypoplastic amelogenesis imperfecta (AIH2) to the long arm of chromosome 4. The disease gene was localized to a 17.6-cM region between the markers D4S392 and D4S395. The albumin gene (ALB), located in the same interval, was a candidate gene for autosomal dominant AI (ADAI) since albumin has a potential role in enamel maturation. Here we describe refined mapping of the AIH2 locus and the construction of marker maps by radiation hybrid mapping and yeast artificial chromosome (YAC)-based sequence tagged site-content mapping. A radiation hybrid map consisting of 11 microsatellite markers in the 5-cM interval between D4S409 and D4S1558 was constructed. Recombinant haplotypes in six Swedish ADAI families suggest that the disease gene is located in the interval between D4S2421 and ALB. ALB is therefore not likely to be the disease-causing gene. Affected members in all six families share the same allele haplotypes, indicating a common ancestral mutation in all families. The AIH2 critical region is less than 4 cM and spans a physical distance of approximately 4 Mb as judged from radiation hybrid maps. A YAC contig over the AIH2 critical region including several potential candidate genes was constructed.

Localization of a gene for oculodentodigital syndrome to human chromosome 6q22-q24

Oculodentodigital syndrome (ODD) is a congenital, autosomal dominant disorder which affects the development of the face, eyes, limbs and dentition. Spastic paraparesis is thought to be an occasional manifestation of the disorder. Type III syndactyly, which occurs as part of ODD, has also been reported to occur as an isolated entity. In the current investigation, a total genome search for the location of the ODD locus was instigated and linkage to polymorphic markers located on chromosome 6q established (pairwise Zmax = 9.37; theta = 0.001). Analysis of a large family with type III syndactyly, but atypical facial features, further suggested that isolated type III syndactyly is also located in this same region of the genome.

High-dose chemotherapy supported by peripheral blood progenitor cells in poor prognosis metastatic breast cancer--phase I/II study. Edinburgh Breast Group

Current treatments for metastatic breast cancer are not associated with significant survival benefits despite response rates of over 50%. High-dose therapy with autologous bone marrow transplantation (ABMT) has been investigated, particularly in North America, and prolonged survival in up to 25% of women has been reported, but with a significant treatment-related mortality. However, in patients with haematological malignancies undergoing autologous transplantation, haematopoietic reconstruction is significantly quicker and mortality lower than with ABMT, when peripheral blood progenitor cells (PBPCs) are used. In 32 women with metastatic breast cancer, we investigated the feasibility of PBPC mobilisation with high-dose cyclophosphamide and granulocyte colony-stimulating factor (G-CSF) after 12 weeks' infusional induction chemotherapy and the subsequent efficacy of the haematopoietic reconstitution after conditioning with melphalan and either etoposide or thiotepa. PBPC mobilisation was successful in 28/32 (88%) patients, and there was a rapid post-transplantation haematopoietic recovery: median time to neutrophils > 0.5 x 10(9) l-1 was 14 days and to platelets > 20 x 10(9) l-1 was 10 days. There was no procedure-related mortality, and the major morbidity was mucositis (WHO grade 3-4) in 18/32 patients (56%). In a patient group of which the majority had very poor prognostic features, the median survival from start of induction chemotherapy was 15 months. Thus, PBPC mobilisation and support of high-dose chemotherapy is feasible after infusional induction chemotherapy for patients with metastatic breast cancer, although the optimum drug combination has not yet been determined.

European Gene Mapping Project (EUROGEM): breakpoint panels for human chromosomes based on the CEPH reference families. Centre d'Etude du Polymorphisme Humain

Meiotic breakpoint panels for human chromosomes 2, 3, 4, 5, 6, 7, 8, 9, 10, 13, 14, 15, 17, 18, 20 and X were constructed from genotypes from the CEPH reference families. Each recombinant chromosome included has a breakpoint well-supported with reference to defined quantitative criteria. The panels were constructed at both a low-resolution, useful for a first-pass localization, and high-resolution, for a more precise placement. The availability of such panels will reduce the number of genotyping experiments necessary to order new polymorphisms with respect to existing genetic markers. This paper shows only a representative sample of the breakpoints detected. The complete data are available on the World Wide Web (URL http:/(/)www.icnet.uk/axp/hgr/eurogem++ +/HTML/data.html) or by anonymous ftp (ftp.gene.ucl.ac.uk in/pub/eurogem/maps/breakpoints).

Atrophic gastric changes in both Helicobacter felis and Helicobacter pylori infected mice are host dependent and separate from antral gastritis

BACKGROUND/AIMS

The role of host factors has been neglected in studies of the pathogenesis of Helicobacter associated disease. The aim of this study was to assess the response of different mouse strains to infection with a single strain of Helicobacter felis.

METHOD

Six strains of inbred mice were infected with the identical H felis culture and were killed at one month, two months, and six months after infection to assess histopathological changes. In addition, two strains of mice were infected with a mouse adapted strain of H pylori and examined at six months after infection.

RESULTS

In SJL, C3H/He, DBA/2, and C57BL/6 infected mice, severe to moderate chronic active gastritis was observed only in the body of the stomach, which increased in severity over time with specialised cells in the body glands being replaced. As the severity of this damage in the body increased and atrophic changes were seen, the level of bacterial colonisation of the antrum decreased. In contrast, in BALB/c and CBA mice, there was only mild gastritis in the antrum, no remarkable changes were detected in their body mucosa, and no atrophy was seen over time. In both these strains of mice, heavy bacterial colonisation was seen, which tended to increase over the period of the experiment. Of particular importance in this experiment was that bacterial colonisation was mainly restricted to the antrum yet the atrophy, when present, was only observed in the body of the stomach. H pylori infected C3H/He mice showed moderate colonisation of the antrum, which persisted up to six months with little development of atrophy. In contrast, H pylori in C57BL/6 mice showed excellent colonisation of the antrum at two months but six months after infection there was moderate to severe body atrophy, which was associated with a loss of bacteria from the antrum.

CONCLUSIONS

These findings challenge current concepts of the development of Helicobacter induced atrophy in that active chronic gastritis of antrum or the body mucosa, or both, is not a prerequisite. They also suggest an autoimmune basis for the pathology although no autoantibody or antibody to the H+/K+ ATPase was detected. Loss of infecting helicobacters from the stomach together with development of an atrophic gastritis in the body of the stomach is similar to the pattern found in certain H pylori infected human subjects.

A multivariate approach to the prediction of hypnotic susceptibility

The present study examined the relation between various self-report measures and two measures of hypnotizability within a multivariate framework. A group of 748 participants was tested on the Harvard Group Scale of Hypnotic Susceptibility, Form A (HGSHS:A), the Tellegen Absorption Scale (TAS), as well as the Preference for an Imagic Cognitive Style (PICS) questionnaire. One hundred ninety of these participants also completed the Paranormal Experiences Questionnaire (PEQ). Data were analyzed using hierarchical multiple regression equations, and the results of the analyses indicated that both the TAS and PICS accounted for significant amounts of unique variance in each of two 373-member samples of HGSHS:A scores. A further sub-sample of participants (n = 161) was tested on the Stanford Hypnotic Susceptibility Scale, Form C (SHSS:C) to see if these results would generalize to another measure of hypnotizability. Hierarchical multiple regression analyses revealed that although the PEQ predicted significant amounts of unique SHSS:C variance over and above that predicted by the TAS, the PICS failed to do so. This inconsistency in results may be due in part to the generally low intercorrelation between the different hypnotizability scales and points to the need to develop new predictor variables that are orthogonal to each other.

Plant responses to short- and long-term exposures to high carbon dioxide levels in closed environments

When higher plants are exposed to elevated levels of CO2 for both short- and long-term periods photosynthetic C-gain and photoassimilate export from leaves are generally increased. Water use efficiency is increased on a leaf area basis. During long-term exposures, photosynthesis rates on leaf and whole plants bases are altered in a species specific manner. The most common pattern in C3 plants is an enhanced rate of whole plant photosynthesis in a well irradiated canopy. Nevertheless, in some herbaceous species prolonged exposure to high CO2 results in remobilization of nitrogenous reserves (i.e., leaf protein degradation) and reduced rates of mature leaf photosynthesis when assayed at ambient CO2 and O2 levels. Both short- and long-term exposures to those CO2 levels (i.e., 100 to 2,000 microliter l-1) which modify photosynthesis and export, also modify both endogenous ethylene gas (C2H4) release, and substrate, 1-aminocyclopropane-1-carboxylic acid (ACC), saturated C2H4 release rates from irradiated leaves. Photosynthetically active canopy leaves contribute most of the C2H4 released from the canopy. Prolonged growth at high CO2 results in a persistent increase in the rate of endogenous C2H4 release from leaves which can, only in part, be attributed to the increase of the endogenous pools of C2H4 pathway intermediates (e.g., methionine, M-ACC, and ACC). The capacity for increasing the rate of C2H4 release in response to short-term exposures to varying CO2 levels does not decline after prolonged growth at high CO2. When leaves, whole plants, and model canopies of tomato plants are exposed to exogenous C2H4 a reduction in the rate of photosynthesis can, in each case, be attributed to the classical effects of C2H4 on plant development and morphology. The effect of C2H4 on CO2 gas exchange of plant canopies is shown to be dependent on the canopy leaf area index.