A meta-analytic review of the correlation between peripheral oxytocin and cortisol concentrations

The stress dampening effects of exogenous oxytocin in humans have been well documented. However, the relation between endogenous oxytocin and cortisol is poorly understood. We conducted a meta-analysis on the correlation between oxytocin and cortisol levels measured at baseline (k = 24, N = 739). The effect size for the baseline correlation statistic was small (Pearson r = 0.163, p = 0.008), with high heterogeneity (I² = 67.88%). Moderation analysis revealed that studies where participants anticipated an experimental manipulation evidenced a greater positive correlation compared to those that did not (Pearson r = 0.318, p = 0.006). A supplementary analysis including additional studies indicated that oxytocin levels in unextracted samples were 60 times higher when using this questionable practice. The findings suggest that the interplay between oxytocin and cortisol is dynamic and sensitive to the anticipation of stress or novelty. Furthermore, extraction of oxytocin appears to be an essential methodological practice.     

The association of somatic arousal with the symptoms of upper airway resistance syndrome

ObjectivesWe tested the hypothesis that the symptoms of upper airway resistance syndrome (UARS) are manifestations of chronic stress. To accomplish this, we utilized the score on a self-report questionnaire for somatic arousal (a component of stress) to compare somatic arousal between UARS patients and healthy controls and, among all participants, to correlate the level of somatic arousal with the severity of UARS symptoms.MethodsWe administered the Mood and Anxiety Symptom Questionnaire anxious arousal subscale (MASQaas; a 17-item questionnaire with increasing levels of arousal scored 17–85) to 12 UARS patients and 12 healthy controls and compared scores between groups. For all participants, we correlated the MASQaas scores with scores for the Epworth Sleepiness Scale (ESS), Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) scale, Pittsburgh Sleep Quality Index (PSQI), SF-36 Health Survey, and Perceived Deficits Questionnaire (PDQ; assessing cognitive function).ResultsCompared to healthy controls, UARS patients demonstrated increased somatic arousal (MASQaas scores of 18 ± 2 and 28 ± 7, respectively; p < 0.0001). For all participants, the MASQaas scores correlated significantly with scores of the ESS (r = 0.64; p = 0.0008), the FACIT-Fatigue scale (r = −0.89; p < 0.0001), the PSQI (r = 0.70; p = 0.0002), SF-36 Physical component (r = −0.78; p < 0.0001), SF-36 Mental component (r = −0.74; p < 0.0001), and the PDQ (r = 0.89; p < 0.0001).ConclusionsOur findings suggest that UARS patients have increased levels of the stress component, somatic arousal, proportionate to the severity of their symptoms.     

Tyrosine metabolism during interferon-alpha administration: Association with fatigue and CSF dopamine concentrations

Chronic exposure to interferon (IFN)-alpha, an innate immune cytokine, produces high rates of behavioral disturbances, including depression and fatigue. These effects may be mediated by the actions of IFN-alpha on dopamine (DA) metabolism in the basal ganglia. Diminished conversion of phenylalanine (Phen) to tyrosine (Tyr), the primary amino acid precursor of DA, has been associated with inflammation, and may reflect decreased activity of the enzyme phenylalanine-hydroxylase (PAH). This study investigated the peripheral Phen/Tyr ratio in relation to cerebrospinal fluid (CSF) concentrations of DA and its metabolites in subjects treated with IFN-alpha plus ribavirin for hepatitis C and controls awaiting IFN-alpha therapy. Plasma Phen/Tyr ratios were significantly increased in IFN-alpha-treated subjects (n = 25) compared to controls (n = 9), and were negatively correlated with CSF DA (r = −0.59, df = 15, p < 0.05) and its metabolite, homovanillic acid (r = −0.67, df = 15, p < 0.01), and positively correlated with fatigue (r = 0.44, df = 23, p < .05) in IFN-alpha-treated patients but not controls. Given the role of tetrahydrobiopterin (BH4) in the PAH conversion of Phen to Tyr, CSF concentrations of BH4 and its inactive oxidized form, dihydrobiopterin (BH2), were examined along with CSF interleukin (IL)-6 in a subset of patients. BH2 concentrations were significantly increased in IFN-alpha-treated patients (n = 12) compared to controls (n = 7), and decreased CSF BH4 concentrations correlated with increased CSF IL-6 (r = −0.57, df = 12, p < 0.05). These results indicate that IFN-alpha is associated with decreased peripheral conversion of Phen to Tyr, which in turn is associated with reduced DA in the brain as well as fatigue. These alterations may be related to oxidation of BH4 secondary to IFN-alpha-induced activation of a CNS inflammatory response.     

Muscle ultrasound measurements and functional muscle parameters in non-dystrophic myotonias suggest structural muscle changes

Patients with non-dystrophic myotonias, including chloride (myotonia congenita) and sodium channelopathies (paramyotonia congenita/potassium aggravated myotonias), may show muscular hypertrophy in combination with some histopathological abnormalities. However, the extent of muscle changes has never been assessed objectively in a large group genetically confirmed patients. This study quantitatively determines echo intensities, thicknesses, ranges-of-motion and force of four skeletal muscles in 63 genetically confirmed patients. The main findings revealed elevated echo intensities in all muscles except the rectus femoris (+1.3–2.2 SD, p < 0.0001), and hypertrophy in the arms (+0.5–0.9 SD, p < 0.01). Muscle echo intensities were inversely correlated to the corresponding ranges-of-motion (biceps brachii: r = ?0.43; p < 0.001, forearm flexors: r = ?0.47; p < 0.001, rectus femoris: r = ?0.40; p = 0.001, and tibial anterior: r = ?0.27; p = 0.04) and correlated positively to age (r = 0.22; p = 0.05). The echo intensity of the forearm flexors was inversely correlated to their muscles’ force (r = ?0.30; p = 0.02). Together, these data suggest that non-dystrophic myotonias may lead to structural muscle changes.     

Cross sectional area reference values for sonography of peripheral nerves and brachial plexus

ObjectiveUltrasound measurements of the cross sectional area (CSA) variability have been recently introduced to quantify pathological changes in peripheral nerves (PN).MethodsReference values from 75 healthy subjects and their correlation to age, height, weight and sex are reported.ResultsThe mean values in PN were: (1) intranerve CSA-variability: median 1.05 (SD ± 0.13), ulnar 1.53 (SD ± 0.51), fibular 1.33 (SD ± 0.37), tibial 1.39 (SD ± 0.39), (2) internerve CSA-variability 1.76 (SD ± 0.37), (3) intraplexus CSA-variability 1.52 (SD ± 0.37), (4) side-to-side difference ratio of the CSA-variability: median 1.21 (SD ± 0.04), ulnar 1.2 (SD ± 0.25), fibular 1.19 (SD ± 0.23), tibial 1.28 (SD ± 0.24) and brachial plexus 1.19 (SD ± 0.23). CSA did not correlate with height in PN, but correlated with weight in the ulnar nerve [Guyon’s canal, r = 0.411, p = 0.0237, elbow r = 0.409, p = 0.0248]. Significant changes between sex were found only in the ulnar (Guyon’s canal, p = 0.0265), fibular (popliteal fossa, p = 0.0336) and sural nerve (p = 0.048). CSA decreased with age in the median (axilla, p = 0.0236), and radial nerve (spiral groove, p = 0.0037) and increased in the tibial nerve (ankle, p < 0.0001).ConclusionsThe CSA reference values reported seem to correlate at certain sites with age, weight and sex but not with height.SignificanceThe new CSA variability measures may be helpful in investigating pathologies of the PN.     

Cumulative meta-analysis of interleukins 6 and 1β, tumour necrosis factor α and C-reactive protein in patients with major depressive disorder

Cumulative meta-analyses are used to evaluate the extent to which further studies are needed to confirm or refute a hypothesis. We used this approach to assess observational evidence on systemic inflammation in individuals with major depressive disorder. We identified 58 studies of four common inflammatory markers in a literature search of PubMed, Embase and PsychInfo databases in May 2014. Pooled data from the earliest eight studies already showed an association between interleukin-6 concentrations and major depression; 23 more recent studies confirmed this finding (d = 0.54, p < 0.0001). A significant association between C-reactive protein levels and major depression was noted after 14 studies and this did not change after addition of six more studies (d = 0.47, p < 0.0001). For these two inflammatory markers, there was moderate heterogeneity in study-specific estimates, subgroup differences were small, and publication bias appeared to be an unlikely explanation for the findings. Sensitivity analyses including only high-quality studies and subjects free of antidepressant medication further verified the associations. While there was a link between tumour necrosis factor-α levels and major depression (d = 0.40, p = 0.002), the cumulative effect remained uncertain due to the extensive heterogeneity in study-specific estimates and inconsistencies between subgroups. No evidence was found for the association between interleukin-1β levels and major depression (d = −0.05, p = 0.86). In conclusion, this cumulative meta-analysis confirmed higher mean levels of interleukin-6 and C-reactive protein in patients with major depression compared to non-depressed controls. No consistent association between tumour necrosis factor-α, interleukin-1β and major depression was observed. Future studies should clarify the specific immune mechanisms involved as well as continue testing anti-inflammatory therapies in patients suffering from major depression.     

Neutrophil Gelatinase-Associated Lipocalin and depression in patients with chronic heart failure

Depression adversely affects prognosis in heart failure (HF) patients. Inflammation is indicated as potential biological pathway in this co-morbidity. Since increased levels of the cytokine Neutrophil Gelatinase-Associated Lipocalin (NGAL) are predictive for HF prognosis, and recently indicated in patients with major depression, this study examined the association of serum NGAL levels with symptoms of depression in patients with HF. Serum NGAL levels were measured in 104 patients with HF (left ventricular ejection fraction, LVEF ⩽ 40). Depression, evaluated using the Beck Depression Inventory (BDI; total score, somatic and cognitive component), and the Hamilton Depression Rating scale (HAMD), at baseline and 12 months follow-up, was associated with NGAL levels using mixed model analysis. Analyses were adjusted for demographics measures, disease severity indicators, inflammation, comorbidity and medication. Increased serum NGAL levels were significantly associated with depression measured by HAMD (baseline: r = 0.25, p < .05) and BDI (baseline: r = 0.22, p < .05; 12 months: r = 0.37, p < .01). This association remained significant after adjustment for covariates; age, sex, time, LVEF, and creatinine (HAMD, t = 2.01, p = .047; BDI, t = 2.28, p = .024). NGAL was significantly associated with somatic- (p = 0.004), but not cognitive depressive symptoms (p = 0.32). NGAL levels were associated with the experienced HF-related functional limitations (6 min walk test), rather than the severity of cardiac dysfunction (LVEF). This study indicates that depression in patients with chronic HF is associated with elevated NGAL levels, independent of clinical severity of the underlying disease.     

Pulmonary capillary wedge pressure and pulmonary arterial pressure in heart failure patients with sleep-disordered breathing

BackgroundThere is a high prevalence of central sleep apnea (CSA) in patients with chronic heart failure (CHF). The present study investigates the hypotheses that CSA in CHF patients reflects heart failure severity as measured by cardiac index (CI), pulmonary artery pressure (PAP) and pulmonary capillary wedge pressure (PCWP).MethodsIn 105 patients with stable CHF (NYHA ? II, LV-EF ? 40%) cardiorespiratory polygraphy and simultaneous right and left heart catheterization was performed.ResultsCSA was present in 58% and obstructive sleep apnea (OSA) in 23% of patients. In CSA patients, PAP and PCWP were significantly higher when compared to patients without SDB. In CSA patients, but not in OSA patients, PCWP showed a significant correlation with apnea–hypopnea index (AHI; r = 0.41, p = 0.005), apnea index (AI; r = 0.44, p = 0.003) and central AI (cAI; r = 0.358, p = 0.015). Cardiac index was more impaired in CSA (1.93 ± 0.5 l/min/m²) than in OSA patients (2.55 ± 1.0 l/min/m²) or those without SDB (2.22 ± 0.4 l/min/m²). A negative correlation of CI and cAI (r = ?0.344, p = 0.008), AI (r = ?0.31, p = 0.02) and AHI (r = ?0.21, p < 0.05) was documented exclusively in CSA patients.ConclusionThe present study supports the hypotheses that the occurrence and severity of CSA in CHF patients reflects heart failure severity.     

Circulating tumour necrosis factor is highly correlated with brainstem serotonin transporter availability in humans

Preclinical studies demonstrate that pro-inflammatory cytokines increase serotonin transporter availability and function, leading to depressive symptoms in rodent models. Herein we investigate associations between circulating inflammatory markers and brainstem serotonin transporter (5-HTT) availability in humans. We hypothesised that higher circulating inflammatory cytokine concentrations, particularly of tumour necrosis factor (TNF-α), would be associated with greater 5-HTT availability, and that TNF-α inhibition with etanercept (sTNFR:Fc) would in turn reduce 5-HTT availability. In 13 neurologically healthy adult women, plasma TNF-α correlated significantly with 5-HTT availability (rho = 0.6; p = 0.03) determined by [¹²³I]-beta-CIT SPECT scanning. This association was replicated in an independent sample of 12 patients with psoriasis/psoriatic arthritis (rho = 0.76; p = 0.003). Indirect effects analysis, showed that there was a significant overlap in the variance explained by 5-HTT availability and TNF-α concentrations on BDI scores. Treatment with etanercept for 6–8 weeks was associated with a significant reduction in 5-HTT availability (Z = 2.09; p = 0.03; r = 0.6) consistent with a functional link. Our findings confirm an association between TNF-α and 5-HTT in both the basal physiological and pathological condition. Modulation of both TNF-α and 5-HTT by etanercept indicate the presence of a mechanistic pathway whereby circulating inflammatory cytokines are related to central nervous system substrates underlying major depression.     

Effects of ebselen versus nimodipine on cerebral vasospasm subsequent to experimental subarachnoid hemorrhage in rats

We investigated the effect of ebselen relative to nimodipine in an animal model of subarachnoid hemorrhage. Thirty Wistar albino rats were divided into 5 groups: G1, no intervention; G2, sham surgery without subarachnoid hemorrhage (SAH); G3, SAH only; G4, SAH plus nimodipine treatment; G5, SAH plus ebselen treatment. For G2 animals, physiological saline (0.9% NaCl) was injected into the cisterna magna. For G3, G4 and G5 animals, SAH was induced by injecting autologous non-heparinized blood into the cisterna magna. One hour after injection, G4 animals received nimodipine at 6-hour intervals and G5 animals received ebselen twice a day for 48 hours. After treatment, brain tissue and blood samples were taken for biochemical and histopathological examination. Mean malonyldialdehyde concentration was significantly higher in G3 than in G1 (p < 0.0001), G2 (p = 0.01), G4 (p = 0.002) and G5 (p = 0.014), and significantly higher in G5 than in G1 (p = 0.013). Mean superoxide dismutase activity was significantly lower in G4 than in both G1 (p = 0.025) and G2 (p = 0.02). Mean wall thickness was significantly greater in G3 than in G1 (p < 0.0001), G2 (p = 0.01), G4 (p < 0.0001) and G5 (p < 0.0001). Mean wall thickness was also significantly greater in both G1 and G2 than in G4 (p < 0.0014 and p < 0.0001) and G5 (p < 0.0001 and p < 0.0001). Mean luminal diameter of the basilar artery was significantly smaller in G3 than in G2 (p = 0.02), G4 (p < 0.018) and G5 (p < 0.001). Our results confirm that ebselen may have neuroprotective effects by acting to prevent vasospasm.     

Efficacy and safety of doxepin 6 mg in a model of transient insomnia

IntroductionThe efficacy and safety of doxepin (DXP) 6 mg tablets were evaluated in healthy adults in a model of transient insomnia.MethodsThis was a randomized, double-blind, parallel-group, placebo-controlled study in healthy adults using a model of transient insomnia. A first-night effect combined with a 3-h phase advance was implemented to induce transient insomnia in healthy adults. Subjects received a single night time dose of placebo (PBO; N = 282) or DXP 6 mg (N = 283) in a sleep laboratory. Efficacy was evaluated objectively (polysomnography; PSG) and subjectively (morning questionnaire). Consistent with the model utilized, the primary endpoint was latency to persistent sleep (LPS); secondary PSG endpoints included wake after sleep onset (WASO; key secondary endpoint), total sleep time (TST), wake time after sleep (WTAS) and sleep efficiency (SE; overall, by quarter of the night and hourly); secondary subjective endpoints included latency to sleep onset (LSO), subjective WASO (sWASO), subjective TST (sTST) and sleep quality.ResultsDXP 6 mg demonstrated statistically significant improvements in LPS (13 min decrease versus PBO; p < 0.0001), WASO (39 min less than PBO; p < 0.0001), TST (51 min more than PBO; p < 0.0001), WTAS (p < 0.0001), overall SE (p < 0.0001), SE in each quarter of the night (p < 0.0001) and SE in each of the 8 h (p ? 0.0003), all versus PBO. Additionally, DXP 6 mg significantly improved subjective variables including LSO (p < 0.0001), sWASO (p = 0.0063), sTST (p < 0.0001), and sleep quality (p = 0.0004), versus PBO. There was no consistent evidence of next-day residual sedation and also minor sleep stages alterations. The incidence of adverse events was comparable to placebo.ConclusionsIn this model of transient insomnia, DXP 6 mg demonstrated significant improvements in sleep onset, sleep maintenance, sleep duration and sleep quality, and also appeared to reduce early morning awakenings. These data suggest that DXP 6 mg may be effective and well tolerated in adults experiencing transient insomnia.     

Treadmill walking effects on grip strength in young men with Down syndrome

This study was aimed at investigating the relation between grip strength and anthropometric factors and the impact of an aerobic exercise on grip strength in young men with Down syndrome (DS). This study was a pre-post design. Twelve males with DS were assigned to an exercise group, who walked using an incremental protocol on a treadmill for 20 min at aerobic levels. Eight additional persons with DS were assigned to an attentional control group, who watched a video. Measure of grip strength was tested pre- and post-interventions. The results showed positively significant relationship among grip strength and age (r = .74, p < .01), weight (r = .52, p = .02), body mass index (r = .61, p = .01) and waist circumference (r = .54, p = .02). In addition, Grip strength was slightly improved after exercise (p = .03) but decreased after control condition. The results showed that anthropometric factors, such as age, weight, body mass index and waist circumference, were positively correlated with grip strength in young men with DS. Further, improvement in grip strength can be found even after a single exercise session. This finding emphasizes the importance of maintaining an active lifestyle in persons with DS for performing activities of daily living.     

Las concentraciones de glutamina y citrulina reflejan la síntesis del óxido nítrico en el sistema nervioso humano

IntroductionAlthough citrulline is produced by nitric oxide (NO) synthase upon activation of the NMDA glutamate receptor, nitrite and nitrate (NO_x) concentration is considered the best marker of NO synthesis, as citrulline is also metabolised by other enzymes. This study analyses the correlation between human cerebrospinal fluid NO_x and citrulline concentrations in order to determine the extent to which citrulline reflects NO synthesis and glutamatergic neurotransmission.MethodsParticipants were patients with acute neurological diseases undergoing lumbar puncture (n = 240). NO_x and amino acid concentrations were determined by HPLC.ResultsNO_x concentrations did not vary significantly where infection (p = 0,110) or inflammation (p = 0,349) were present. Multiple regression analysis showed that NO_x concentration was correlated with glutamine (r = –0,319, p < 0,001) and citrulline concentrations (r = 0,293, p = 0,005) but not with the citrulline/arginine ratio (r = –0,160, p = 0,173). ANCOVA confirmed that NO_x concentration was correlated with citrulline concentration (F = 7,6, p = 0,007) but not with the citrulline/arginine ratio (F = 2,2, p = 0,136), or presence of infection (F = 1,8, p = 0,173) or inflammation (F = 1,4, p = 0,227). No association was found between NO_x and arginine or glutamate concentrations.ConclusionThe results suggest that CSF citrulline concentration reflects NO_x synthesis to some extent, despite the contribution of other metabolic pathways. In addition, this study shows that glutamine is an important modulator of NO synthase activity, and that arginine and glutamate are not correlated with NO_x.     

Association of IL-12p70 and IL-6:IL-10 ratio with autism-related behaviors in 22q11.2 deletion syndrome: A preliminary report

22q11.2 deletion syndrome (22q11DS) is a genetic disorder that conveys a significant risk for the development of social behavior disorders, including autism and schizophrenia. Also known as DiGeorge syndrome, 22q11DS is the second most common genetic disorder and is characterized by an elevated risk for immune dysfunction, up to 77% of individuals have an identifiable immune deficiency. We hypothesize that this immune dysfunction could contribute to the elevated risk of impaired social behavior seen in 22q11DS. The current study begins to elucidate these immune deficits and link them with the behavioral alterations associated with the disorder. Serum concentrations of a series of cytokines were examined, using a multiplex immunoassay, in sixteen individuals with 22q11DS and screened for autism-related behavior using the Autism Diagnostic Interview-Revised (ADI-R). This preliminary study examined correlations between specific immune proteins and each of the ADI-R algorithm scores (social, communication, and repetitive behavior). The inflammatory cytokine IL-1β, as well as the ratio between the inflammatory cytokine IL-6 and the anti-inflammatory cytokine IL-10, were correlated with social scores (r = 0.851, p = 0.004; r = 0.580, p = 0.018). In addition, the inflammatory cytokines interferon gamma and IL-12p70 were correlated with repetitive behaviors (r = 0.795, p = 0.033; r = 0.774, p = 0.002). Interestingly, IL-12 has been reported to be increased in autistic children. These data show a positive association between severity of autism-related behaviors and level of serum concentrations of inflammatory cytokines in individuals with 22q11DS, providing a basis for further inquiry.     

Psychological and neuropsychological assessment of regular hoasca users

BackgroundHoasca (also called ayahuasca) is a N,N-dimethyltryptamine (DMT) – containing psychedelic brew originally used for magico-religious purposes by Amerindian populations of the Amazon Basin. Recently, Brazilian syncretic churches have helped spread the ritual use of hoasca to Western societies. The aim of this study was to evaluate substance use, and neuropsychological and psychological functioning of regular hoasca users within a religious setting.MethodsAssessment of socio-economic status, mood, personality traits, impulsiveness, drug use, quality of life, extrinsic and intrinsic religiosity, and neuropsychological function was performed on 30 volunteers from a U.S. branch of União do Vegetal (UDV), a Brazilian religion which uses hoasca ritually. We also assessed 27 non-hoasca-using control subjects matched by socio-demographic profile and church attendance. Mann–Whitney U, chi-squared and Fisher tests were used to analyze differences between groups. Spearman's association and simple logistic regression tests were used to analyze the impact of frequency of hoasca use on dependent variables.ResultsRelative to the control group, the UDV group demonstrated lower scores for depression (p = 0.043, r = .27) and confusion (p = 0.032, r = .29) as assessed by the Profile of Mood States (POMS); higher scores on the instrument Big Five Inventory (BFI) for the personality traits agreeableness (p = 0.028, r = .29) and openness (p = 0.037, r = .28); higher scores on the quality life domain role limitations due to physical health as determined by the instrument Medical Outcomes Study Short Form-36 – SF-36 (p = 0.035, r = .28); less recent use of alcohol (p < 0.001, φ_c = .57), greater past use of alcohol to intoxication (p = 0.007, φ_c = .36) and past use of cannabis (p = 0.001, φ_c = .45) as measured by the Addiction Severity Index (ASI), 5th edition; better score on a measure of memory vulnerability to proactive interference as measured by the California Verbal Learning Test – CVLT (p = 0.040, r = .27). Lifetime use of hoasca was positively correlated with role limitations due to physical health (p = 0.032, r_s = .39) and negatively associated with lifetime heavy alcohol use (p = 0.034, OR = 0.979).ConclusionsThe findings indicate that religious use of hoasca does not adversely affect neuropsychological functioning and may have positive effects on substance abuse and mood.     

Peripheral expression of MAPK pathways in Alzheimer’s and Parkinson’s diseases

Alteration of mitogen-activated protein kinase pathways may cause aberrant protein phosphorylation and enhanced apoptosis in Alzheimer’s disease (AD) and Parkinson’s disease (PD). Increased susceptibility of lymphocytes to apoptosis has been reported in AD. To our knowledge this is the first study to investigate the expression and phosphorylation status of p38 mitogen-activated protein kinase (p38MAPK) and c-Jun N-terminal kinase (JNK) in peripheral blood lymphocytes of 20 AD and 20 PD patients and 20 healthy controls using western blot analysis. Compared with controls, no significant difference of total p38MAPK or JNK levels were observed in AD and PD patients, whereas phosphorylated p38MAPK and phosphorylated JNK levels were significantly increased in the AD and PD groups (p < 0.001). However, the increased levels of the two phosphorylated kinases in AD versus PD patients presented no significant difference. Interestingly, phosphorylated p38MAPK and phosphorylated JNK levels were positively correlated with disease duration (r = 0.602, p = 0.005 and r = 0.561, p = 0.010, respectively) and negatively correlated with the Mini Mental State Examination score (r = −0.664, p = 0.001 and r = −0.578, p = 0.008, respectively) in AD patients. No correlations between protein levels and clinical variables were found in PD patients. Investigation of peripheral changes in the expression of p38MAPK and JNK may lead to the development of innovative biomarkers of neurodegenerative diseases, particularly for AD.     

An association between neuropeptide Y levels and leukocyte subsets in stress-exacerbated asthmatic mice

Neuropeptide Y (NPY) was recently proposed to be associated with stress and airway inflammation; however, this has rarely been studied in animal models of asthma. Twenty-four C57BL/6 mice were randomly divided into 3 groups of 8 each: naive control group, asthma group (with an established asthma model), and stressed asthma group (with established asthma and stress models). Bronchoalveolar lavage (BAL) fluid was collected for total cell counts using a hemocytometer and for cytological examinations by Wright stain. Differential inflammatory cell counts were performed to identify eosinophils, macrophages, neutrophils, and lymphocytes. NPY and corticosterone serum levels were determined with enzyme immunoassay kits. Stress was associated with increased airway inflammatory response, which was manifested by the accumulation of total leukocytes and eosinophils in the BAL fluid in comparison with the asthma and the control groups. The levels of NPY (p < 0.05) and corticosterone (p < 0.01) were elevated in the stressed asthma group in comparison with the control and asthma groups. The concentration of NPY and corticosterone positively correlated with the total leukocyte count (r = 0.892, p < 0.05 and r = 0.937, p < 0.01 respectively) and eosinophil numbers (r = 0.806, p = 0.053 and r = 0.885, p < 0.01 respectively).Stress may be associated with elevated peripheral NPY level, which was observed to be associated with exacerbated airway inflammation in asthmatic mice.     

Association between gout and vertigo in a Taiwanese population

There are reports of an association between benign paroxysmal positional vertigo and hyperuricemia. We sought to determine the risk of vertigo among patients with gout compared with the general population, using a nationwide Taiwanese population-based claims database. Our study cohort consisted of patients with a diagnosis of gout disorders in 2004 (N = 18 773). Four age- and gender-matched controls for every patient in the study cohort were selected using random sampling as the comparison cohort (N = 75 092). All subjects were followed from the date of cohort entry until they developed vertigo or to the end of 2006. Cox proportional hazard regressions were performed to evaluate the 3-year vertigo-free survival rates. Of the total sample, 2563 (incidence, 10.09 per 1000 person-years) had vertigo during the 3-year follow-up period: 570 (incidence, 11.78 per 1000 person-years) from the study cohort and 1993 (incidence, 9.69 per 1000 person-years) from the comparison cohort. The adjusted hazard ratios (HR) of peripheral and central vertigo in patients with gout compared with controls during the 2–3-year follow-up were 1.17 (95% confidence interval [CI] = 1.05–1.29, p = 0.003) and 1.08 (95% CI = 0.86–1.36, p = 0.53), respectively. This is the first population-based study performed to suggest that patients with gout may have an increased risk of peripheral vertigo but not central vertigo. Benign paroxysmal positional vertigo may be the reason for the observed association; however, future studies are required to further ascertain the relationship between gout and the various causes of peripheral vertigo.