The Interaction of Oxytocin and Social Support, Loneliness, and Cortisol Level in Major Depression.

OBJECTIVE: Loneliness is a specific risk factor for depressive symptoms and suicidal behavior. The present study examined whether the serum oxytocin level would interact with social support and buffers loneliness and hypothalamic-pituitary-adrenal (HPA)-axis activity in drug-naïve patients with major depressive disorder (MDD). METHODS: Twenty-six patients with MDD (male:female = 3:23; mean age, 45.54 ± 12.97 years) were recruited. The 17-item Hamilton Depression Rating Scale, UCLA Loneliness Scale and self-reported Measurement of Support Function Questionnaire were administered. Serum oxytocin and cortisol levels were assessed using a commercial immunoassay kits. RESULTS: In MDD patients, a negative association was found between degrees of social support and loneliness (ß= -0.39, p = 0.04). The interaction between social support and serum oxytocin level was negatively associated with loneliness (ß= -0.50, p = 0.017) and serum cortisol level (ß= -0.55, p = 0.020) after adjusting for age. Follow-up analyses showed that the association between higher social support and lower loneliness was observed only in the higher-oxytocin group (r = -0.75, p = 0.003) but not in the lower group (r = -0.19, p = 0.53). The significance remained after further adjusting for sex and depression severity. CONCLUSION: Low oxytocin level is a vulnerability factor for the buffering effect of social support for loneliness and aberrant HPA-axis activity in MDD patients.

Allergenicity and toxicology of inhaled silver nanoparticles in allergen-provocation mice models.

Silver nanoparticles (AgNP) have been associated with the exacerbation of airway hyperresponsiveness. However, the allergenicity and toxicology of AgNP in healthy and allergic individuals are unclear. We investigated the pathophysiological responses to AgNP inhalation in a murine model of asthma. Continuous and stable levels of 33 nm AgNP were maintained at 3.3 mg/m(3) during the experimental period. AgNP exposure concomitant with ovalbumin challenge increased the enhanced pause (Penh) in the control and allergic groups. AgNP evoked neutrophil, lymphocyte and eosinophil infiltration into the airways and elevated the levels of allergic markers (immunoglobulin E [IgE] and leukotriene E4 [LTE4]), the type 2 T helper (Th2) cytokine interleukin-13 (IL-13), and oxidative stress (8-hydroxy-2'-deoxyguanosine [8-OHdG]) in healthy and allergic mice. Bronchocentric interstitial inflammation was observed after AgNP inhalation. After inhalation, the AgNP accumulated predominantly in the lungs, and trivial amounts of AgNP were excreted in the urine and feces. Furthermore, the AgNP induced inflammatory responses in the peritoneum. The inhalation of AgNP may present safety concerns in healthy and susceptible individuals.

Comparative proteomics of inhaled silver nanoparticles in healthy and allergen provoked mice.

BACKGROUND: Silver nanoparticles (AgNPs) have been associated with the exacerbation of asthma; however, the immunological basis for the adjuvant effects of AgNPs is not well understood. OBJECTIVE: The aim of the study reported here was to investigate the allergic effects of AgNP inhalation using proteomic approaches. METHODS: Allergen provoked mice were exposed to 33 nm AgNPs at 3.3 mg/m(3). Following this, bronchoalveolar lavage fluid (BALF) and plasma were collected to determine protein profiles. RESULTS: In total, 106 and 79 AgNP-unique proteins were identified in the BALF of control and allergic mice, respectively. Additionally, 40 and 26 AgNP-unique proteins were found in the plasma of control and allergic mice, respectively. The BALF and plasma protein profiles suggested that metabolic, cellular, and immune system processes were associated with pulmonary exposure to AgNPs. In addition, we observed 18 proteins associated with systemic lupus erythematosus that were commonly expressed in both control and allergic mice after AgNP exposure. Significant allergy responses were observed after AgNP exposure in control and allergic mice, as determined by ovalbumin-specific immunoglobulin E. CONCLUSION: Inhaled AgNPs may regulate immune responses in the lungs of both control and allergic mice. Our results suggest that immunology is a vital response to AgNPs.

No changes in striatal dopamine transporter in antidepressant-treated patients with major depression.

Selective serotonin reuptake inhibitors and serotonin norepinephrine reuptake inhibitors are the mainstay treatment for major depressive disorder, but whether their therapeutic mechanisms involve the dopaminergic system remains inconclusive. Eight participants with major depressive disorder were administered single-photon emission computed tomography with [(99m)Tc] TRODAT-1 both before and after 24 weeks of antidepressant treatment to evaluate the change in striatal dopamine transporter (DAT) availability. All participants were responders (≥50% reduction in Hamilton Depression Rating Scale score). The DAT availability did not change (P=0.58), as the Hamilton Depression Rating Scale score decreased (P=0.02). Striatal DAT availability remains intact during long-term antidepressant treatment in patients with major depressive disorder.

Assessments of inclinations of the mandibular fossa by computed tomography in an Asian population.

This study aims to evaluate the inclinations of right and left sides the mandibular fossa in Asian population using computed tomography (CT) images and determine its effects according to the parameters of gender, age, and asymmetry. CT images of the heads of 198 Asian subjects [95 females aged 44.2 ± 20.7 years, range 11-88 years; and 103 males aged 44.5 ± 19.7 years, range 15-98 years] were selected. The following eight parameters characterizing the inclinations of the mandibular fossa were measured by medical imaging software: anterior and posterior inclinations on the left and right sides on a sagittal view, and medial and lateral inclinations on the left and right sides on a coronal view. The anterior inclination was significant steeper in males than in females on both the left and right sides. A moderate positive correlation was found between age and anterior inclinations on the left and right sides. None of the other parameters were significantly affected by age or gender. None of the parameters differed significantly between the right and left sides of the mandibular fossa in males, females, or all subjects. The anterior inclination of the mandibular fossa was affected by aging and gender becoming steeper in Asians males than females. Besides, there were no asymmetry in the right and left side inclinations of the mandibular fossa.