Intrahippocampal infusion of ebselen impairs retention of an inhibitory avoidance task in rats

Ebselen is a seleno-compound used in the treatment of neurological disorders involving the glutamatergic system. Although ebselen is currently used in clinical trials, the physiological effects of this seleno-compound are poorly known. In this study, we investigated the effects of intrahippocampal infusion of ebselen (0.1-3 nmol) in rats submitted to an inhibitory avoidance task. Ebselen (1-3 nmol) infused after the training session impaired retention of inhibitory avoidance, tested 90 min or 24 h after the training session. Moreover, ebselen also impaired the retention when infused 30 min prior to training or 10 min prior to test sessions. In summary, ebselen impaired memory consolidation, acquisition and retrieval. This amnesic effect of ebselen could be related to oxidant activity at N-methyl-D-aspartate (NMDA) receptors. Our results indicate that more studies must be performed to investigate the mechanisms of this amnesic effect and whether ebselen has a cognition-impairing effect when administered chronically.

Effect of pre-operative anxiolysis on postoperative pain response in patients undergoing total abdominal hysterectomy

In a double blind, placebo-controlled trial, we have assessed the effects of pre-operative anxiolysis on postoperative pain scores in 112 ASA I-II women, aged 18-65 years, scheduled to undergo total abdominal hysterectomy. Subjects were randomly allocated to receive either oral diazepam 10 mg (n=56) or placebo (n=56) pre-operatively. Postoperative anxiety, pain scores, analgesic consumption, and sedation were evaluated at several time points during the first 24 h following surgery. Postoperative pain scores were found to be significantly higher in the diazepam group. Trait and state anxiety showed a significant effect on pain scores, independent of the treatment group. No difference was found between the groups in morphine consumption, but there was a significant reduction in morphine consumption with time.

Effect of orally administered guanosine on seizures and death induced by glutamatergic agents

Intraperitoneal guanosine has been shown to prevent quinolinic acid-induced seizures in mice. In this study, we investigated the effect of orally administered guanosine on seizures induced by the glutamate agonists quinolinic acid and kainate, and the endogenous glutamate releaser alpha-dendrotoxin. Guanosine (7.5 mg/kg, per os), administered 75 min in advance, prevented 70% of seizures induced by i.c.v. quinolinic acid, being as efficient as the NMDA channel blocker MK-801 administered intraperitoneally. Guanosine was ineffective against kainate-induced seizures, but significantly reversed the potentiation of seizures and death caused by the concomitant injection of MK-801. Guanosine also significantly prevented seizures and death induced by i.c.v. alpha-dendrotoxin, whereas MK-801 and phenobarbital only prevented death. Altogether, our findings underscore the therapeutic potential of oral administration of guanosine for treating diseases involving glutamatergic excitotoxicity, including epilepsy.

Risk factors for postoperative anxiety in adults

We identified risk factors for postoperative anxiety and quantified their effect on 712 adults between 18 and 60 years of age (ASA I-III physical status) undergoing elective surgery under general anaesthesia, neural blockade or both. The measuring instruments were a structured questionnaire, a pain visual analogue scale, the McGill Pain Questionnaire, the State-Trait Anxiety Inventory, the Montgomery-Asberg Depression Rating Scale, a Self-Reporting Questionnaire-20, and a Self-Perception of Future Questionnaire. Multivariate conditional regression modelling taking into account the hierarchical relationship between risk factors revealed that postoperative anxiety was associated with ASA status III (OR = 1.48), history of smoking (1.62), moderate to intense postoperative pain (OR = 2.62) and high pain rating index (OR = 2.35), minor psychiatric disorders (OR = 1.87), pre-operative state-anxiety (OR = 2.65), and negative future perception (OR = 2.20). Neural block anaesthesia (OR = 0.72), systemic multimodal analgesia (OR = 0.62) and neuroaxial opioids with or without local anaesthesia (OR = 0.63) were found to be protective factors against postoperative anxiety.

Transcript map of the 8p23 putative tumor suppressor region

Cancers of the head and neck, prostate, liver, and bladder exhibit minimal regions of deletion within chromosomal band 8p23 that either overlap or map very close to one another. We previously refined a minimal region of deletion in squamous cell carcinomas to a 112-kb interval within 8p23. There seems to be only a single gene within this region that is expressed in normal upper aerodigestive tract epithelium. This candidate for the squamous cancer suppressor, CUB and sushi multiple domains-1 (CSMD1), extends into the minimal regions of deletions defined for the other types of cancer with 8p23 deletions. RT-PCR and EST data indicate that CSMD1 is also expressed in those organs,making this gene a candidate for a suppressor of multiple types of cancer. Both the sequence of the gene and the organization of the protein are highly conserved in the mouse.

Risk factors for preoperative anxiety in adults

BACKGROUND

Patients who undergo surgery experience acute psychological distress in the preoperative period. The objective of this study was to identify and quantify the effect of risk factors for preoperative anxiety in adults.

METHODS

A cross-sectional study was performed with 592 inpatients scheduled for elective surgery. Age ranged from 18 to 60 years (ASA physical status I-III). Demographic information was collected using a structured questionnaire. The measuring instruments were a visual analog scale, the State-Trait Anxiety Inventory; the Montgomery-Asberg Depression Rating Scale, the WHO Self-Reporting Questionnaire-20, and the future self-perception questionnaire. Multivariate conditional regression modeling was used to control confounding factors and to determine independent predictors of preoperative anxiety, taking into account the hierarchical relationship between risk factors.

RESULTS

High preoperative anxiety was associated with history of cancer (odds ratio (OR)=2.26) and smoking (OR=7.47), psychiatric disorders (OR=5.93), negative future perception (OR= 2.30), moderate to intense depressive symptoms (3.22), high trait-anxiety (3.83), moderate to intense pain (2.12), medium surgery (OR=1.52), female gender (OR=2.0), ASA category III (OR=3.41), up to 12 years of education (OR=1.36), and more than 12 years of education (OR=1.68). Previous surgery (OR= 0.61) was associated with lower risk for preoperative state-anxiety.

CONCLUSIONS

History of cancer and smoking, psychiatric disorders, negative future perception, moderate to intense depressive symptoms, high trait-anxiety, moderate to intense pain, medium surgery, female gender, ASA category III, up to 12 years of education and more than 12 years of education constituted independent risk factors for preoperative state-anxiety. Previous surgery reduced the risk for preoperative anxiety.

LL-37, the neutrophil granule- and epithelial cell-derived cathelicidin, utilizes formyl peptide receptor-like 1 (FPRL1) as a receptor to chemoattract human peripheral blood neutrophils, monocytes, and T cells

We have previously shown that antimicrobial peptides like defensins have the capacity to mobilize leukocytes in host defense. LL-37 is the cleaved antimicrobial 37-residue, COOH-terminal peptide of hCAP18 (human cationic antimicrobial protein with a molecular size of 18 kD), the only identified member in humans of a family of proteins called cathelicidins. LL-37/hCAP18 is produced by neutrophils and various epithelial cells. Here we report that LL-37 is chemotactic for, and can induce Ca(2+) mobilization in, human monocytes and formyl peptide receptor-like 1 (FPRL1)-transfected human embryonic kidney 293 cells. LL-37-induced Ca(2+) mobilization in monocytes can also be cross-desensitized by an FPRL1-specific agonist. Furthermore, LL-37 is also chemotactic for human neutrophils and T lymphocytes that are known to express FPRL1. Our results suggest that, in addition to its microbicidal activity, LL-37 may contribute to innate and adaptive immunity by recruiting neutrophils, monocytes, and T cells to sites of microbial invasion by interacting with FPRL1.

Guanosine impairs inhibitory avoidance performance in rats

The nucleoside guanosine, previously found to exert trophic and neuroprotective effects, was found to impair retention of inhibitory avoidance responses, with a complete effect at 7.5 mg/kg i.p. pretraining. Treated animals, when retrained 1 week later, showed normal learning ability. Guanosine injected immediately after training or pretest did not alter retention latency. Combined pretraining and pretest treatments with guanosine failed to reverse its amnestic effect, excluding the contribution of state dependency. Open field parameters and shock sensitivity were mostly unaltered by guanosine. These results suggest an amnestic effect of guanosine on inhibitory avoidance in rats, in a pattern compatible with inhibition of glutamatergic activity. However, the mechanism for the amnestic effect of guanosine is yet to be elucidated.

Guanosine and GMP prevent seizures induced by quinolinic acid in mice

In the mammalian CNS, glutamate and GABA are the principal neurotransmitters mediating excitatory and inhibitory synaptic events, respectively, and have been implicated in the neurobiology of seizures. Guanine-based purines, including the nucleoside guanosine and the nucleotide GMP, have been shown to antagonize glutamatergic activity at the receptor level and the other purine nucleoside adenosine is a well-known modulator of seizure threshold. In the present study we investigated the anticonvulsant effect of i. p. guanosine and GMP against seizures induced by the glutamate agonist quinolinic acid (QA) or the GABA(A) antagonist picrotoxin in mice. Animals were pretreated with an i.p. injection of saline, guanosine or GMP 30 min before either an i.c.v. injection of 4 microliter QA (36.8 nmol) or a subcutaneous injection of picrotoxin (3.2 mg/kg). All animals pretreated with vehicle followed by QA or picrotoxin presented seizures, which were completely prevented by the NMDA antagonist MK-801 and the GABA agonist phenobarbital, respectively. Guanosine and GMP dose-dependently protected against QA-induced seizures, up to 70 and 80% at 7.5 mg/kg, with ED(50)=2. 6+/-0.4 and 1.7+/-0.6 mg/kg, respectively. Conversely, neither guanosine, GMP nor MK-801 affected picrotoxin-induced seizures, indicating some degree of specificity towards the glutamatergic system. This study suggests anticonvulsant properties of i.p. guanosine and GMP, which may be related with antagonism of glutamate receptors.

Homozygous deletions define a region of 8p23.2 containing a putative tumor suppressor gene

Loss of heterozygosity at microsatellite loci in chromosomal band 8p23.2 is a frequent event in squamous cell carcinomas of the head and neck, suggesting that this region contains a putative tumor suppressor. Allelic loss studies on laryngeal and oral/oropharyngeal tumors have restricted the size of this region to approximately 1 cM. A similar pattern of deletions is also observed in prostatic and ovarian adenocarcinomas. As part of an effort to identify this gene by positional cloning, we developed a physical contig consisting of 12 overlapping bacterial artificial chromosome (BAC) clones spanning this interval. We developed sequence-tagged sites from the ends of these BACs and used them, along with seven microsatellite loci, to detect and map homozygous deletions in four head and neck squamous cancer cell lines. Our mapping analysis further restricted the consensus minimal region of deletion to a <191-kb interval.

Multiple regions of deletion on chromosome arm 13q in head-and-neck squamous-cell carcinoma

Several lines of evidence suggest that the progression of head-and-neck squamous-cell carcinoma (HNSCC) involves inactivation of at least one and possibly several tumor-suppressor genes on the long arm of chromosome 13. The fact that neither Rb1 nor BRCA2 appears to be inactivated in the majority of head-and-neck cancers suggests that novel tumor-suppressor genes are involved. We have used microsatellite repeat polymorphisms and PCR to detect several distinct minimal regions of deletion on 13q in supraglottic and oral squamous-cell carcinomas. One region maps to 13q34, the second to 13q14.3 and a potential third region, not reported in previous studies, maps to 13q12.1. Overall, 69% of the 145 tumors examined demonstrated allelic loss at one or more loci on 13q. We investigated whether a novel suppressor candidate mapping to 13q14. 3-q21, leukemia-associated gene 1, might also be involved in the progression of squamous-cell carcinomas. Multiplexed PCR revealed homozygous deletion of leu1 in one oral cavity tumor. This suggests that this gene or one nearby may be the actual target of deletions in this region of the chromosome arm.

Localization of a putative tumor suppressor gene in the sub-telomeric region of chromosome 8p

Several regions of chromosome arm 8p are frequently deleted in a variety of human malignancies including those of the prostate, head and neck, lung, and colon, suggesting that there is more than one tumor suppressor gene on this chromosome arm. Both laryngeal and oral squamous cell carcinomas exhibit three distinct and nonoverlapping regions of deletion on 8p. We have further refined the localization of the putative suppressor in 8p23 by using eight microsatellite loci to create a high resolution deletion map of 150 squamous cell carcinomas of the larynx and oral cavity. These new data demonstrate that there are two distinct classes of deletion within this relatively small region of the chromosome and suggest two possible locations for the gene within the D8S264 to D8S1788 interval. We also determined that there is little difference between the allelic loss frequencies of microsatellites mapping near the telomeric ends of other chromosome arms and loci mapping to more centromere proximal regions of the same arm. These data suggest that the high allelic loss frequencies seen at 8p23 loci are not the result of a generalized instability of chromosome ends and are instead consistent with the activation of a specific suppressor gene.