Serotonin transporter polymorphism, memory and hippocampal volume in the elderly: association and interaction with cortisol

The s allele variant of the serotonin transporter gene (5-HTT) has recently been observed to moderate the relationship of stress to depression and anxiety. To date no study has considered interactive effects of 5-HTT genotype, stress and hypothalamic-pituitary-adrenal (HPA) function on cognition in healthy, older adults, which may reflect developmental, functional or neurodegenerative effects of the serotonin transporter polymorphism. We investigated whether 5-HTT genotype interacts with cumulative life stress and HPA-axis measures of waking and diurnal cortisol slope to impact cognition in 154 non-depressed, older adults. Structural images of hippocampal volume were acquired on a subsample of 56 participants. The 5-HTT s allele was associated with both significantly lower delayed recall and higher waking cortisol levels. Presence of the s allele interacted with higher waking cortisol to negatively impact memory. We also observed a significant interaction of higher waking cortisol and the s allele on lower hippocampal volume. Smaller hippocampi and higher cortisol were associated with lower delayed recall only in s allele carriers. No impact or interactions of cumulative life stress with 5-HTT or cortisol were observed. This is the first investigation to identify an association of the 5-HTT s allele with poorer memory function in older adults. The interactive effects of the s allele and waking cortisol levels on reduced hippocampal volume and lower memory suggest that the negative effect of the serotonin polymorphism on memory is mediated by the HPA axis. Further, given the significant association of the s allele with higher waking cortisol in our investigation, future studies may be needed to evaluate the impact of the serotonin transporter polymorphism on any neuropsychiatric or behavioral outcome which is influenced by HPA axis function in older adults.

One-dimensional beam ordering of protons in a storage ring

The ordering of protons has been observed at a new storage ring, S-LSR, at Kyoto University. Abrupt jumps in the momentum spread and the Schottky noise power were observed for protons for the first time at a particle number of approximately 2000, upon applying electron cooling with electron currents of 25, 50, and 100 mA. The transition temperature was 0.17 and 1 meV in the longitudinal and transverse directions, respectively. The transverse temperature of the proton beam was much below that of electrons at the transition, which played an essential role in the ordering of protons.

Radiation-induced genomic instability in tandem repeat sequences is not predictive of unique sequence instability

Tandem repeat sequences, classified as minisatellite sequences or partially duplicated genes, are inherently unstable. Radiation exposure can increase the instability of such repeat sequences, but the biological consequences of this elevated instability are not well characterized. To learn more about the characteristics of the instability at different sequences in the genome, we created mutant HT1080 cells bearing 8.4 kb of partially duplicated allele at the HPRT locus by gene targeting. The cells were then tested to determine whether repeat-sequence instability (assessed by elevated reversion rate caused by loss of one duplicated segment) accompanied increased forward mutation rates at the restored wild-type HPRT allele. After a 4-Gy X irradiation, 32 clones were selected (out of 500 clones, 6%) that showed elevated reversion rates even after many cell generations. These clones also showed general increases in the forward mutation rate, whereas the paired individual mutation rates did not correlate with each other. Furthermore, levels of intracellular reactive oxygen species (ROS) and nuclear gamma-H2AX foci, which are hallmarks for DNA damage responses, were also generally elevated, although the levels did not correlate with the individual reversion rates. It was concluded that repeat sequence instability is not predictive of unique sequence instability, probably because the instability is generated by multiple mechanisms after radiation exposure.

Acceleration of chemokine production from endothelial cells in response to lipopolysaccharide in hyperglycemic condition

Chronic hyperglycemia is an established risk factor for endothelial damage. It remains unclear, however, whether brief hyperglycemic episodes after acute stress alter the function of vascular endothelial cells in response to endotoxin. We hypothesize that brief hyperglycemic episodes enhance the production of interleukin-8 (IL-8) after lipopolysaccharide (LPS) stimulation.

METHODS

Human umbilical vein endothelial cells (HUVECs; 1 x 10(5) cells/mL, cells from subcultures 2-5, n = 6) were cultivated in various concentrations of glucose (200, 300, 400, and 500 mg/dL) with or without LPS stimulation (1 microg/mL) for 24 hours. After culture, IL-8 levels in the supernatant were measured using ELISA.

RESULTS

HUVECs cultured at glucose concentrations of 300 and 400 mg/dL produced more (p < 0.01) IL-8 than control cells (200 mg/dL). HUVECs cultured at glucose concentrations of 300 and 400 mg/dL also produced more (p < 0.01) IL-8 than those cultured in the absence of LPS.

CONCLUSIONS

Hyperglycemic conditions enhance IL-8 production by vascular endothelial cells, and this response is augmented by LPS. Infections may foster neutrophil accumulation at injury sites. These results suggest that it is important to manage even short-term increases in blood glucose after acute stress.

Clinical characteristics of postoperative contralateral intracranial hematoma after traumatic brain injury

OBJECTIVES

To investigate the clinical characteristics of contralateral intracranial hematoma (ICH) after traumatic brain injury.

METHODS

The subjects included 149 patients with traumatic ICH treated by hematoma evacuation. The patients were retrospectively divided into a bilateral ICH (B-ICH) group and unilateral ICH (U-ICH) group after craniotomy using brain CT scans for comparison of the following parameters: complicated expanded brain bulk from the cranial window, hypotension during craniotomy, and outcome.

RESULTS

Post-craniotomy brain CT scans revealed U-ICH in 106 patients and B-ICH in 43 patients. Average Glasgow Coma Scale on arrival did not differ between the groups, but a higher proportion of patients in the B-ICH group deteriorated after admission (p = 0.02). The B-ICH patients also exhibited a significantly higher rate of expanded brain bulk from the cranial window (p < 0.05). No significant difference was observed between the groups with hypotension during craniotomy. The B-ICH group exhibited a lower rate of favorable outcome (p < 0.05) and higher mortality (p < 0.05).

CONCLUSION

The B-ICH patients had a worse outcome than the U-ICH patients. Contralateral ICH was difficult to forecast based on pre- and intraoperative clinical conditions. Subdural hematoma or contusional ICH was frequently observed as a contralateral ICH.

Rewarming following accidental hypothermia in patients with acute subdural hematoma: case report

A 57-year-old man was admitted to the Emergency and Critical Care Department with accidental hypothermia (31.5 degrees C) after resuscitation from cardiopulmonary arrest (CPA). Brain CT revealed an acute subdural hematoma. Active core rewarming to 33 degrees C was performed using an intravenous infusion of warm crystalloid. The patient underwent craniotomy soon after admission, with bladder temperature maintained at 33 to 34 degrees C throughout the surgery. Therapeutic hypothermia (34 degrees C) was continued for 2 days, followed by gradual rewarming. After rehabilitation, the patient was able to continue daily life with assistance. Traumatic brain injury (TBI) following CPA is associated with extremely unfavorable outcomes. Very few patients with acute subdural hematomas presenting with accidental hypothermia and CPA have been reported to recover. No suitable strategies have been clearly established for the rewarming performed following accidental hypothermia in patients with TBI. Our experience with this patient suggests that therapeutic hypothermia might improve the outcome in some patients with severe brain injury. It also appears that the method used for rewarming might play an important role in the therapy for TBI with accidental hypothermia.

Spatial test for agricultural pesticide "blow-in" effect on prevalence of Parkinson's disease

The current study used Department of Veteran's Affairs (VA) clinical records, State of California pesticide application records, spatial maps of distribution of Parkinson's disease patients, and pesticide applications to determine if there was evidence for "blow-in" of pesticides as a factor in explaining the prevalence of Central Valley Parkinson's disease. The results did not support the hypothesis of increasing prevalence of Parkinsonism attributable to wind drift.

Naevus lipomatosus cutaneous superficialis on the nose

Naevus lipomatosus cutaneous superficialis (NLCS) is an uncommon hamartomatous lesion with an exceptional presentation on the face. We report the case of an elderly patient who presented with a classic type of NLCS on the right nasal orifice. This patient was taking inhaled steroids for his allergic rhinitis during 35 years.

Tonsil size and body mass index are important factors for efficacy of simple tonsillectomy in obstructive sleep apnoea syndrome

OBJECTIVES

To evaluate the efficacy of simple tonsillectomy to treat obstructive sleep apnoea syndrome (OSAS) in adults.

DESIGN

Prospective study.

SETTING

Tertiary referral centre.

PARTICIPANTS

Thirty patients (28 males) underwent simple tonsillectomy under general anaesthesia. The patients' mean age was 33.2 +/- 6.8 years and body mass index was 30.7 +/- 6.0 kg/m2. Seven patients (23%) were classified with grade 4, 16 patients (53%) with grade 3, and seven patients (23%) with grade 2 according to the tonsil size of Friedman's classification.

MAIN OUTCOME MEASURES

The number of apnoea episodes per hour (apnoea index), the number of apnoea and hypopnoea episodes per hour (apnoea-hypopnoea index), lowest nocturnal oxygen saturation and oxygen desaturation time were measured during overnight polysomnography before and after surgery. A successful tonsillectomy was defined as an apnoea-hypopnoea index improvement ratio of > or =50% and an apnoea-hypopnoea index <20 after operation.

RESULTS

Apnoea-hypopnoea index decreased from 69.0 +/- 28.4/h to 30.1 +/- 24.0/h (P < 0.0001). Simple tonsillectomy was successful in all six patients with body mass index <25 kg/m2. Concerning success rate of simple tonsillectomy with tonsil, size 2 was lowest (42.9%). Eight of the 13 patients who used continuous positive airway pressure before simple tonsillectomy did not use continuous positive airway pressure after simple tonsillectomy because of a significant reduction of excessive daytime sleepiness. Continuous positive airway pressure decreased significantly after simple tonsillectomy from 13.6 +/- 2.5 cmH2O preoperatively to 10.6 +/- 1.3 cmH2O postoperatively (P < 0.05).

CONCLUSIONS

These data suggest that simple tonsillectomy is a beneficial modality to treat OSAS in selected patients (larger tonsil, low body mass index), even in adults.

Importance of including Blomia tropicalis in the routine diagnosis of Venezuelan patients with persistent allergic symptoms

BACKGROUND

Blomia tropicalis is a common mite found in the house dust of many tropical countries including Venezuela. The prevalence of skin test and specific serum immunoglobulin (Ig)E reactivity to B. tropicalis in Venezuela has not been previously evaluated.

METHODS

In the present study we evaluated the skin reactivity by skin prick test and specific IgE by a multiple antigen blot assay, against B. tropicalis and Dermatophagoides pteronyssinus, in a group of 115 subjects who attended the Allergy Clinic of the Institute of Biomedicine, Caracas, Venezuela, and we studied possible cross reactions between similar proteins of these two mites.

RESULTS

One hundred and six patients with persistent allergic respiratory symptoms showed a positive skin prick test to at least one of the mite extracts, with the frequency of positive reactions to B. tropicalis being as high as to D. pteronyssinus. Twelve patients reacted only to D. pteronyssinus and 13 different patients only to B. tropicalis. Specific IgE to each of the mite extracts was found with similar frequency, and the results coincided with the skin test reactivity.

CONCLUSIONS

The study indicated the importance of including B. tropicalis in routine diagnostic testing in tropical and sub-tropical situations.

Use of a VA pharmacy database to screen for areas at high risk for disease: Parkinson's disease and exposure to pesticides

The purpose of this study was to assess whether pharmacy database information from US Department of Veterans Affairs (VA) medical centers could be used to screen for areas of higher Parkinson's disease prevalence in patients exposed to pesticides. The authors used pharmacy data sets and compared the use of antiparkinsonian medications at 2 VA medical centers in California: one in Palo Alto, near the ocean, and one in Fresno, downwind from extensively farmed parts of the Central Valley. They found that patients at Fresno had higher odds ratios (1.5-1.8) for the use of Parkinson's disease medications than patients at Palo Alto. These data are consistent with the observations of prior epidemiologic studies and suggest that VA pharmacy databases can prioritize locations for further epidemiologic research. However, a thorough exploration of alternative explanations is needed to reach definitive conclusions regarding the findings suggested by this method.

Energetic protons from a few-micron metallic foil evaporated by an intense laser pulse

With detailed experimental studies and hydrodynamics and particle-in-cell simulations we investigate the role of the prepulse in laser proton acceleration. The prepulse or pedestal (amplified spontaneous emission) can completely evaporate the irradiated region of a sufficiently thin foil; therefore, the main part of the laser pulse interacts with an underdense plasma. The multiparametric particle-in-cell simulations demonstrate that the main pulse generates the quasistatic magnetic field, which in its turn produces the long-lived charge separation electrostatic field, accelerating the ions.

Sequential constriction of upper airway and vocal cords in sleep apnoea of multiple system atrophy: low field magnetic resonance fluoroscopic study

Low field magnetic resonance fluoroscopy was used to clarify temporal and spatial features of airway obstruction in sleep apnoea syndrome (SAS) in multiple system atrophy (MSA), as well as in obstructive SAS (OSAS). 20 patients with OSAS with severe obesity (mean (SD) age 66 (10) years; 16 men, 4 women) and 6 patients with SAS related to probable MSA (60 (9) years; 4 men, 2 women) were studied. In the OSAS group, body mass index, apnoea index, and desaturation index were significantly higher than in the MSA group. In OSAS, simultaneous obstruction extended from the retropalatal pharynx to the retroglossal during sleep on low field magnetic resonance fluoroscopy. In MSA, obstruction of upper airway followed a similar distribution, but obstruction of vocal cords followed upper airway obstruction. In contrast to OSAS, sequentially acting neural mechanisms are suspected in SAS with MSA.

Differential changes in messenger RNA expressions and binding sites of neuropeptide Y Y1, Y2 and Y5 receptors in the hippocampus of an epileptic mutant rat: Noda epileptic rat

The anti-convulsive effects of neuropeptide Y have been suggested in several animal models of epilepsy. We have found the sustained increase of neuropeptide Y contents and the seizure-induced elevation of hippocampal messenger RNA in a novel spontaneous epileptic mutant rat: Noda epileptic rat. In the present study, we investigated the change of neuropeptide Y Y1 and Y2 receptor messenger RNA expressions and binding sites in the hippocampus following a spontaneous generalized tonic-clonic seizure of Noda epileptic rat. Furthermore, the binding sites of a more recently isolated receptor subtype, neuropeptide Y Y5 receptors, were also evaluated by receptor autoradiography. A marked elevation of neuropeptide Y immunoreactivity in the mossy fiber, and Y2-receptor up-regulation in the dentate gyrus were observed in the hippocampus of Noda epileptic rat, which coincided with the previous results of the other epileptic models. In contrast, Y1-receptor down-regulation was not found after a spontaneous seizure of Noda epileptic rat while this occurs in kindling and after kainic acid-induced seizures. [125I][Leu31, Pro34]peptide YY/BIBP 3226-insensitive (Y5 receptor) binding sites in CA1 stratum radiatum were significantly decreased following a spontaneous seizure of Noda epileptic rat. The present results suggest that a spontaneous seizure of Noda epileptic rat induces significant changes in neuropeptide Y-mediated transmission in the hippocampus via Y2 and Y5 receptors, but not Y1 receptors. Therefore, specific subset of neuropeptide Y receptor subtypes might be involved in the epileptogenesis of Noda epileptic rat.