Increased risk of olfactory and taste dysfunction in the United States psoriasis population.

BACKGROUND: It is plausible that immunopathological processes associated with psoriasis might contribute to the occurrence of olfactory or taste dysfunction. However, the actual association was still unknown. PURPOSE: To determine the relationship between olfactory or taste dysfunction and psoriasis. METHODS: Two cross-sectional studies were performed by using National Health and Nutrition Examination Survey (NHANES) data. Participants with psoriasis were defined as cases and those without psoriasis were identified as controls. Taste and smell self-reported questionnaires were used to define smell/taste alterations and identification tests were used to assure the smell/taste dysfunctions. Logistic regression models with inverse probability treatment weighting (IPTW) strategies were conducted to investigated the relationship between psoriasis and olfactory or taste dysfunction. RESULTS: Self-reported questionnaires indicated that psoriasis patients were more likely to have perceived taste alteration (IPTW-aOR = 1.43) and smell alteration (IPTW-aOR = 1.22). Identification tests revealed that psoriasis was associated with taste dysfunction (IPTW-aOR = 1.28) and olfactory dysfunction (IPTW-aOR = 1.22). Relevant findings showed that psoriasis may be significantly associated with taste or olfactory dysfunction regardless of the questionnaire data or identification examination data used. CONCLUSION: Olfactory and taste dysfunction could be considered comorbidities in patients with psoriasis based on our observational study. Therefore, physicians should be cautious of olfaction and taste alterations among patients with psoriasis.

Lysosomal Dysfunction and Autophagy Blockade Contribute to MDMA-Induced Neurotoxicity in SH-SY5Y Neuroblastoma Cells.

Methylenedioxymethamphetamine (MDMA) is a psychostimulant with high abuse potential and severe neurotoxicity. According to our previous study, MDMA promotes autophagosome accumulation and contributes to cell death in cultured cortical and serotonergic neurons. However, the detailed mechanism underlying autophagy dysfunction remains unclear. Lysosomes play an important role in autophagic degradation. The present study aimed to examine the role of lysosomal function in autophagic flux in neuronal cultures exposed to MDMA. We showed that MDMA induced enlarged vesicles that accumulate in SH-SY5Y neuroblastoma cells. In addition, we demonstrated that MDMA stimulated dynamin-dependent but clathrin-independent endocytosis, which might contribute to vacuole expansion. Morphological and Western blot analyses revealed that MDMA induced lysosomal swelling, whereas the activity of the lysosomal hydrolytic enzymes cathepsin B and cathepsin D was decreased in SH-SY5Y and cultured cortical neurons, which might lead to autophagosome accumulation and autophagic degradation blockage. Intriguingly, inactivation of cathepsins B and D led to cell death and autophagy-lysosomal dysregulation, which mimicked MDMA-induced neurotoxicity. Consequently, impairment of lysosomal proteolysis and blockage of autophagy degradation contributed to MDMA-induced neurotoxicity in neuronal cultures.

Hp-s1 Ganglioside Suppresses Proinflammatory Responses by Inhibiting MyD88-Dependent NF-κB and JNK/p38 MAPK Pathways in Lipopolysaccharide-Stimulated Microglial Cells.

Hp-s1 ganglioside is isolated from the sperm of sea urchin (Hemicentrotus pulcherrimus). In addition to neuritogenic activity, the biological function of Hp-s1 in neuroinflammation is unknown. In this study, we investigated the anti-neuroinflammatory effect of Hp-s1 on lipopolysaccharide (LPS)-stimulated microglial cells. MG6 microglial cells were stimulated with LPS in the presence or absence of different Hp-s1 concentrations. The anti-inflammatory effect and underlying mechanism of Hp-s1 in LPS-activated microglia cells were assessed through a Cell Counting kit-8 assay, Western blot analysis, and immunofluorescence. We found that Hp-s1 suppressed not only the expression of inducible nitric oxide synthase and cyclooxygenase-2 but also the expression of proinflammatory cytokines, such as TNF-α, IL-1ß, and IL-6. Hp-s1 inhibited the LPS-induced NF-κB signaling pathway by attenuating the phosphorylation and translocation of NF-κB p65 and by disrupting the degradation and phosphorylation of inhibitor κB-α (IκBα). Moreover, Hp-s1 inhibited the LPS-induced phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK). Hp-s1 also reduced the expression of myeloid differentiation factor 88 (MyD88) and TNF receptor-associated factors 6 (TRAF6), which are prerequisites for NF-κB and MAPKs activation. These findings indicated that Hp-s1 alleviated LPS-induced proinflammatory responses in microglial cells by downregulating MyD88-mediated NF-κB and JNK/p38 MAPK signaling pathways, suggesting further evaluation as a new anti-neuroinflammatory drug.

Evaluation of brain SERT with 4-[18F]-ADAM/micro-PET and hearing protective effects of dextromethorphan in hearing loss rat model.

This study investigated the protective effects of dextromethorphan (DXM) on noise-induced hearing loss (NIHL) in rats. This study aimed to improve the auditory threshold and to understand the protective effects of DXM against N-methyl-d-aspartate (NMDA)-induced neurite degeneration of serotonergic neurons. The animals were exposed to 8-kHz narrowband noise at a 118-dB sound pressure level for 3.5 h. The hearing thresholds were determined by measuring the auditory brainstem response to click stimuli. Serotonin transporter (SERT) expression was determined through micro-positron emission tomography (PET) using N,N-dimethyl-2-(2-amino-4-18F-fluorophenylthio)benzylamine (4-[18F]-ADAM). We also investigated the effects of DXM on NMDA-induced morphological changes in the primary cultures of rat serotonergic neurons. NIHL significantly improved after prophylactic treatment with DXM (p < .05). SERT density in DXM-treated rats was significantly higher than that in non-DXM-treated rats. Because prophylactic medication restored the NMDA-inhibited neurite length of serotonergic neurons and presented SERT density, DXM could be a potential agent in alleviating NIHL.

Autophagy inhibition plays a protective role against 3, 4-methylenedioxymethamphetamine (MDMA)-induced loss of serotonin transporters and depressive-like behaviors in rats.

The 3,4-methylenedioxymethamphetamine (MDMA) is a popular recreational drug, which ultimately leads to serotonergic (5-HT) neurotoxicity and psychiatric disorders. Previous in vitro studies have consistently demonstrated that MDMA provokes autophagic activation, as well as damage of 5-HT axons and nerve fibers. So far, whether autophagy, a well-conserved cellular process that is critical for cell fate, also participates in MDMA-induced neurotoxicity in vivo remains elusive. Here, we first examined time-course of autophagy-related changes during repeated administration of MDMA (10 mg/kg s.c. twice daily for 4 consecutive days) using immunofluorescent staining for tryptophan hydroxylase and microtubule-associated protein 1 light chain 3 beta in rats. We also evaluated the protective effects of 3-methyadanine (3-MA, an autophagy inhibitor, 15 mg/kg i.p.) against MDMA-induced acute and long-term reductions in serotonin transporters (SERT) density in various brain regions using immunohistochemical staining and positron emission tomography (PET) imaging respectively. Plasma corticosterone measurements and forced swim tests were performed to evaluate the depressive performance. The staining results showed that repeated administration of MDMA increased expression of autophagosome and caused reduction in SERT densities of striatum and frontal cortex, which was ameliorated in the presence of 3-MA. PET imaging data also revealed that 3-MA could ameliorate MDMA-induced long-term decreased SERT availability in various brain regions of rats. Furthermore, immobility time of forced swim tests and plasma corticosterone levels were less in the group of MDMA co-injected with 3-MA compared with that of MDMA group. Together, these findings suggest that autophagy inhibition may confer protection against neurobiological and behavioral changes induced by MDMA.

Health Care Service Utilization After Various Vascular Access Selections.

BACKGROUND: To provide clinicians with sufficient information for selecting optimal access strategies for patients with end-stage renal disease, the utilization of health-care services of patients receiving arteriovenous fistulas (AVFs), arteriovenous grafts (AVGs), and central venous catheters (CVCs) are crucial topics that require investigation. MATERIALS AND METHODS: This study involved 1248, 431, and 323 patients with end-stage renal disease who had received an AVF, AVG, or CVC, respectively. All sampled patients were monitored over the course of a 1-y study period to evaluate their medical utilization. The utilization were further categorized into nephrology and nonnephrology services. This study also performed univariate and multivariate regressions to estimate the effects of vascular accesses. RESULTS: Regarding the utilization of health care services, significant differences were observed for mean outpatient visits (45.30 versus 49.71 versus 48.80), outpatient costs (US$19117 versus US$21015 versus US$19280), inpatient days (9.77 versus 14.41 versus 21.60), inpatient costs (US$2627 versus US$3810 versus US$5238), and total costs (US$21743 versus US$24825 versus US$24518) among patients who had received an AVF, AVG, or CVC, respectively. Furthermore, patients receiving an AVF had lower total costs for all health care services and nonnephrology services than patients undergoing AVG or CVC across the categories of men, women, adults, and elderly individuals. Multiple regressions found that patients undergoing AVF had significantly lower total costs for all health services than patients undergoing other vascular accesses after adjustments. CONCLUSIONS: This study displayed that patients who received an AVF fully used health care and nonnephrology services than patients who received an AVG or CVC.

Regulation of Noise-Induced Loss of Serotonin Transporters with Resveratrol in a Rat Model Using 4-[18F]-ADAM/Small-Animal Positron Emission Tomography.

Serotonin (5-HT) plays a crucial role in modulating the afferent fiber discharge rate in the inferior colliculus, auditory cortex, and other nuclei of the ascending auditory system. Resveratrol, a natural polyphenol phytoalexin, can inhibit serotonin transporters (SERT) to increase synaptic 5-HT levels. In this study, we investigated the effects of resveratrol on noise-induced damage in the serotonergic system. Male Sprague-Dawley rats were anaesthetized and exposed to an 8-kHz tone at 116 dB for 3.5 h. Resveratrol (30 mg/kg, intraperitoneal injection [IP]) and citalopram (20 mg/kg, IP), a specific SERT inhibitor used as a positive control, were administered once a day for four consecutive days, with the first treatment occurring 2 days before noise exposure. Auditory brainstem response testing and positron emission tomography (PET) with N,N-dimethyl-2-(2-amino-4-[18F]fluorophenylthio)benzylamine (4-[18F]-ADAM, a specific radioligand for SERT) were used to evaluate functionality of the auditory system and integrity of the serotonergic system, respectively, before and after noise exposure. Finally, immunohistochemistry was performed 1 day after the last PET scan. Our results indicate that noise-induced serotonergic fiber loss occurred in multiple brain regions including the midbrain, thalamus, hypothalamus, striatum, auditory cortex, and frontal cortex. This noise-induced damage to the serotonergic system was ameliorated in response to treatment with resveratrol and citalopram. However, noise exposure increased the hearing threshold in the rats regardless of drug treatment status. We conclude that resveratrol has protective effects against noise-induced loss of SERT.

Neurotrophic and neuroprotective potential of human limbus-derived mesenchymal stromal cells.

BACKGROUND AIMS: The purpose of this study was to examine neurotrophic and neuroprotective effects of limbus stroma-derived mesenchymal stromal cells (L-MSCs) on cortical neurons in vitro and in vivo. METHODS: Cultured L-MSCs were characterized by flow cytometry and immunofluorescence through the use of specific MSC marker antibodies. Conditioned media were collected from normoxia- and hypoxia-treated L-MSCs to assess neurotrophic effects. Neuroprotective potentials were evaluated through the use of in vitro hypoxic cortical neuron culture and in vivo rat focal cerebral ischemia models. Neuronal morphology was confirmed by immunofluorescence with the use of anti-MAP2 antibody. Post-ischemic infarct volume and motor behavior were assayed by means of triphenyltetrazolium chloride staining and open-field testing, respectively. Human growth antibody arrays and enzyme-linked immunoassays were used to analyze trophic/growth factors contained in conditioned media. RESULTS: Isolated human L-MSCs highly expressed CD29, CD90 and CD105 but not CD34 and CD45. Mesenchymal lineage cell surface expression pattern and differentiation capacity were identical to MSCs derived form human bone marrow and adipose tissue. The L-MSC normoxic and hypoxic conditioned media both promoted neurite outgrowth in cultured cortical neurons. Hypoxic conditioned medium showed superior neurotrophic function and neuroprotective potential with reduced ischemic brain injury and improved functional recovery in rat focal cerebral ischemia models. Human growth factor arrays and enzyme-linked immunoassays measurements showed neuroprotective and growth-associated cytokines (vascular endothelial growth factor [VEGF], VEGFR3, brain-derived neurotrophic factor, insulin-like growth factor -2 and hepatocyte growth factor) contained in conditioned media. Hypoxic exposure caused VEGF and brain-derived neurotrophic factor upregulation, possibly contributing to neurotrophic and neuroprotective effects. CONCLUSIONS: L-MSCs can secrete various neurotrophic factors stimulating neurite outgrowth and protecting neurons against brain ischemic injury through paracrine mechanism.

Investigating the effects of noise-induced hearing loss on serotonin transporters in rat brain using 4-[18F]-ADAM/small animal PET.

The serotonin transporter (SERT) is an important marker of the status of serotonergic neurons. The main function of SERT is to regulate the serotonin concentration in the synapse. Recent studies have shown that SERT is expressed in the central auditory pathway and may play a role in the auditory process. However, little is known about the effects of noise on the cerebral serotonin system. In this study, we explored the status of brain SERT in a rat model of noise-induced hearing loss using 4-[(18)F]-ADAM (a SERT imaging agent) and small animal positron emission tomography (PET) imaging. Male Sprague Dawley rats were exposed to an 8 kHz noise at 118 dB sound pressure level for 3.5h. An auditory brainstem response test and 4-[(18)F]-ADAM/small animal PET were performed at different time points after noise exposure. The specific uptake ratios (SURs) for 4-[(18)F]-ADAM were calculated from the PET imaging data in six brain regions. Immunohistochemistry and surface preparation of the cochleae were performed 30 days after noise exposure. Our data clearly showed that the hearing and cochlear outer hair cells of the rats were lost after noise exposure. In the PET study, the SURs of SERT were markedly reduced by 35%-58% in various brain regions one day after noise exposure. The decrement remained on days 8 and 15 and was approximately 26%-48% on day 29. The distribution and intensity of SERT immunostaining in the brain paralleled the PET imaging data. These results suggest that noise-induced hearing loss involves a reduction in SERT expression in various regions of the rat brain and that changes in SERT are detectable by 4-[(18)F]-ADAM/small animal PET in vivo.

Therapeutic effects of methimazole on 3,4-methylenedioxymethamphetamine-induced hyperthermia and serotonergic neurotoxicity.

3,4-methylenedioxymethamphetamine (MDMA) is a popular recreational drug, however over 200 studies demonstrate that acute (e.g. hyperthermia, rhabdomyolysis) and chronic (e.g. neurotoxicity) toxicity effects of MDMA were observed in different animals. Methimazole (MMI), an inhibitor of thyroid hormone synthesis, was found to significantly reduce the HSP72 expression of heat stress induced in fibroblasts. Hence, we attempted to understand the effects of MMI on MDMA induced changes in vivo. Male SD rats were randomly divided into four groups as follows:(a) water-saline (b) water-MDMA (c) MMI-saline and (d) MMI-MDMA group. In the temperature analysis test, MMI was found to alleviate MDMA-induced hyperthermia and increase the heat loss index (HLI), revealing its peripheral vasodilation effect. PET experiment suggested that MDMA induced elevated glucose uptake by skeletal muscles, which was resolved by MMI pretreatment. IHC staining (serotonin transporter, SERT) showed the evidence of neurotoxicity caused by MDMA (serotonin fiber loss), which was alleviated by MMI. Furthermore, the animal behaviour test (forced swimming test, FST) showed higher swimming time but lower immobility time in MMI-MDMA and MMI-saline groups. Taken together, treatment of MMI shows benefits such as lowered body temperature, alleviation of neurotoxicity and excited behaviour. However, further investigations should be conducted in the future to provide in-depth evidence for its clinical use.

Illicit Drug Use and Smell and Taste Dysfunction: A National Health and Nutrition Examination Survey 2013-2014.

Taste and smell dysfunction are suspected to be associated with substance use. However, representative epidemiological studies remain insufficient. This cross-sectional study explored the relationship between drug use (including cannabis or hashish, cocaine, heroin, and methamphetamine) and olfactory/gustatory dysfunction using data from the 2013-2014 National Health and Nutrition Examination Survey. In this study, participants who completed the smell examination with mean age of 59 were classified into four groups: cannabis users (n = 845), participants without cannabis use (n = 794), illicit drug users (n = 450), and participants without illicit drug use (n = 2000). Participants who completed the taste examination with mean age of 58 were also categorised into four groups: cannabis users (n = 810), participants without cannabis use (n = 714), illicit drug users (n = 428), and participants without illicit drug use (n = 1815). Logistic regression models investigated the association between cannabis or illicit drug use and smell or taste dysfunctions among study participants. Odds ratios and 95% confidence intervals were calculated. Finally, we did not find correlations between illicit drug use and dysfunction of taste or smell senses; our findings were consistent in many subgroup analyses. We recommend that further studies explore the mechanism and dose of illicit drug use that could have chemosensory impacts.

Modified-Dose Pembrolizumab and Prognostic Outcomes among Non-Small Cell Lung Cancer Patients: A Chart Review Study.

The modified dose (MD) regimen of pembrolizumab (2 mg/kg or 100 mg every 3 weeks) is an alternative option to reduce the financial burden resulting from the extremely high cost of the standard dose (SD) regimen (200 mg every 3 weeks). However, the clinical effectiveness and prognostic outcomes have not been fully elucidated in real-word clinical practice. Sixty-four consecutive patients in Taiwan receiving pembrolizumab for advanced NSCLC between 2018 and 2020 were recruited in this study. Comparisons of overall survival (OS) and progression-free survival (PFS) were performed using Kaplan−Meier survival curves. Additionally, 12 predictors, including pembrolizumab regimen, dose, neutrophil-to-lymphocyte ratio (NLR), age, sex, histopathology, smoking history, ECOG PS, EGFR mutation, PD-L1 expression, distant metastases and treatment line, were analyzed in multivariable Cox models for predicting OS and PFS. The results showed that the MD group and the SD group had similar OS and PFS, especially in patients beyond first-line treatment or with a pretreatment NLR < 5. The NLR was the only independent factor associated with both OS (adjusted HR = 0.052; p = 0.010) and PFS (adjusted HR = 0.259; p = 0.021). The results of this study assure the clinical effectiveness of MD pembrolizumab and suggest that the pretreatment NLR could highlight patients who may benefit from MD pembrolizumab.

Protective Effects of Anti-depressants against the Subsequent Development of Psoriasis in Patients with Major Depressive Disorder: a Cohort Study.

BACKGROUND: Inflammation may mediate the relationship between major depressive disorder (MDD) and psoriasis. However, it is unclear whether anti-depressants can decrease the subsequent risk of psoriasis among MDD patients. This study investigated the effects of anti-depressants on the subsequent risk of psoriasis in MDD patients. METHODS: This was a population-based cohort study in Taiwan. 58,454 MDD patients who had received anti-depressants and 6,034 MDD patients who did not receive anti-depressants were included. Each patient was tracked for 5 years to confirm a diagnosis of psoriasis following the index date. Cox proportional hazards models were performed to estimate the hazard ratio (HR) for psoriasis. RESULTS: In this study, after using time-dependent Cox regression with both inverse probability of treatment weighting (IPTW) and adjustment for confounders, anti-depressant users had a significantly lower risk of psoriasis than the nonusers (IPTW-adjusted HR [aHR] = 0.69). Additionally, most types and dosages of anti-depressants tended to protect against psoriasis. Selective serotonin reuptake inhibitor use (IPTW-aHR = 0.67) and low-dose anti-depressant use (IPTW-aHR = 0.66) had significant protective effects even after IPTW and adjustment for confounders. LIMITATIONS: This study had no information about over-the-counter medications. CONCLUSIONS: This study revealed the protective effects of anti-depressants on psoriasis risk in patients with MDD. Antidepressant users had significantly lower risk of psoriasis than the nonusers. Further analyses indicated that the usage of SSRIs and low antidepressant dosage could statistically decrease risk of psoriasis.

Major depressive disorder increased risk of psoriasis: A propensity score matched cohort study.

BACKGROUND: Reports showed that elevated proinflammatory cytokines, as detected in patients with psoriasis, was noted in individuals with major depressive disorder (MDD). Therefore, this study aimed to clarify the association of MDD and prospective incidence of psoriasis in human using a nationwide study. METHOD: This population-based cohort study used the data from the Taiwan National Health Insurance system. 64,486 patients were defined as MDD cohort and 64,486 propensity score matched subjects without MDD were identified as comparison cohort. Each patient was independently tracked for a 5-year study period to assure them for a psoriasis diagnosis after the index date. Stratified Cox proportional hazard models were used to calculate the hazard ratio (HRs) for 5-year psoriasis risk. RESULTS: After adjustments, the HR of psoriasis for MDD patients was 1.32 compared with subjects without MDD. The stratified analyses present that MDD patients had approximately 1.30-fold significantly higher risk of psoriasis than comparison subjects in most subgroups. Furthermore, compared with the matched subjects without MDD, the adjusted HRs of psoriasis in the 2-, 3-, 4- and 5-year study periods were 1.33, 1.32, 1.33 and 1.32, respectively. LIMITATIONS: Several patients with MDD or psoriasis might not include in this study, because of using a medical claims database. CONCLUSIONS: This study provides population-based evidence that MDD is an independent risk factor of developing psoriasis, with an increased risk in the male sex. Additional investigations verifying our findings and exploring possible pathological mechanisms would be of great interest and value to the psychiatric field.

Association of Benzodiazepine Receptor Agonist Use With Changes in Psoriasis Severity in Adult Population: A Population-Based Study.

To date, it remains uncertain whether benzodiazepine receptor agonists (BZRAs) are aggravating factors even though these drugs can elevate the levels of biomarkers associated with the development of psoriasis. Therefore, this study aimed to investigate the association of BZRA use with changes in psoriasis severity. All data were sourced from the National Health Insurance system in Taiwan. We conducted a population-based retrospective cross-sectional study of 15,727 psoriasis patients who received BZRAs (BZRA users), and 18,856 psoriasis patients who did not receive BZRAs (nonusers). At least a 1-year washout period without any BZRA prescriptions was required. The main outcome was the change in psoriasis severity between before and after BZRA exposure. This study detected the exacerbation of psoriasis severity in mild psoriasis population by using a logistic model. Then, this study carried another logistic model among those patients who had severe psoriasis to calculate the odds ratios (ORs) for the improvement of the psoriasis severity. Among patients with mild psoriasis, BZRA users had a significantly higher probability of psoriasis severity exacerbation (IPTW-adjusted OR = 1.46). Mild psoriasis patients who received high and low doses of BZRAs had 1.70- and 1.39-fold higher probabilities of psoriasis severity exacerbation, respectively, than the non-users. Furthermore, in the severe psoriasis population, more low-dose BZRA users improved psoriasis severity than non-users. In conclusion, this study provided clinical evidence of the effects of BZRA use on patients with psoriasis severity. Among patients with mild psoriasis, high-dose BZRA users may be associated with the changes in psoriasis severity. However, low-dose BZRA exposure only slightly exacerbated disease severity among patients with mild psoriasis. Accordingly, clinicians should evaluate the risks and benefits of the BZRA usage.

Illegal Drug Use and Risk of Hearing Loss in the United States: A National Health and Nutrition Examination Survey.

The use of illegal drugs may be a risk factor of hearing loss. However, very few studies with large sample size have investigated the relationship between illegal drug use and hearing loss. Therefore, to evaluate the association between illegal drug use and hearing loss, this cross-sectional population-based study collected data from the US National Health and Nutrition Examination Survey 2011. The study included 1772 participants aged 20 to 59 years who underwent the Drug Use Questionnaire and Audiometry Examination. Of the 1772 participants in this study, 865 were men (48.8%) and 497 were illegal drug users. The mean (SD) age of the patients was 40.0 (11.4) years. After considering age, sex, and comorbidities, the participants who used illegal drugs were found to have higher risks of high-frequency hearing loss (adjusted odds ratio (OR), 1.69; 95% confidence interval (CI), 1.35-2.10) and overall hearing loss (adjusted OR, 1.69; 95% CI, 1.36-2.12) as compared with the nonusers. In the second analysis, the participants who used ≥ 2 types of illegal drugs were associated with higher risks of high-frequency hearing loss (adjusted OR, 1.57; 95% CI, 1.06-2.32) and overall hearing loss (adjusted OR, 1.60; 95% CI, 1.08-2.37). In the third analysis, cocaine use was associated with increased risks of high-frequency hearing loss (adjusted OR, 1.34; 95% CI, 1.01-1.77) and overall hearing loss (adjusted OR, 1.38; 95% CI, 1.04-1.82). The adjusted OR for overall hearing loss in the methamphetamine users was 1.54 (95% CI, 1.05-2.27) as compared with that in the nonusers. This study shows that illegal drug users might have a higher risk of overall hearing loss than nonusers. In addition, the analysis results demonstrated that the more kinds of illegal drugs used, the higher the risk of hearing loss. Further experimental and longitudinal research studies are required to confirm the causal relationship between illegal drug use and hearing loss.

Antidepressants and risk of sudden sensorineural hearing loss: a population-based cohort study.

BACKGROUND: Increasing numbers of animal studies have found that sudden sensorineural hearing loss (SSNHL) is related to the mechanism of serotonergic modulation. However, the relationship between antidepressants and SSNHL is unclear in humans. Therefore, this study aimed to evaluate the association between antidepressant use and risk of SSNHL. METHODS: Data from 218 466 antidepressant users and 1 116 518 nonusers were obtained from the Taiwan Longitudinal Health Insurance Database. We used propensity-score matching (PSM) and inverse-probability treatment weighting (IPTW) to eliminate any bias. Each patient was tracked for 5 years to ascertain whether or not they were diagnosed with SSNHL. Cox proportional-hazard regression analyses were performed to calculate the SSNHL risk. RESULTS: The adjusted hazard ratio (aHR) of SSNHL for antidepressant users was 1.36 compared with nonusers in the full cohort study. The aHR for antidepressant users was 1.44 and 1.49 compared with the nonusers in the IPTW and PSM cohorts, respectively. All classes of antidepressants consistently increased the SSNHL risk. Additionally, patients receiving four classes of antidepressants were associated with a much higher SSNHL risk (aHR, 2.05) and those receiving one or two classes of antidepressants had a relatively lower SSNHL risk. CONCLUSION: Antidepressants increased SSNHL risk, regardless of their class. Furthermore, patients who took a higher number of antidepressant classes showed an increased risk of developing SSNHL than those who took a lower number of antidepressant classes. Therefore, physicians should estimate the risks and benefits of antidepressant use and avoid prescribing antidepressants concurrently.

Study on the neuroprotective effect of fluoxetine against MDMA-induced neurotoxicity on the serotonin transporter in rat brain using micro-PET.

3, 4-Methylenedioxymethamphetamine (MDMA, "ecstasy") has toxic effects on serotonergic neurons in the brain. Our aim was to determine whether N,N-dimethyl-2-(2-amino-4-[(18)F]-fluorophenylthio) benzylamine (4-[(18)F]-ADAM; a serotonin transporter imaging agent) and micropositron emission tomography (micro-PET) can be used to examine in vivo the effect of fluoxetine on MDMA-induced loss of serotonin transporters in rat brain. Male Sprague-Dawley rats were injected with fluoxetine [1 dose, 5 mg/kg, subcutaneously (s.c.)] followed by MDMA (twice a day for 4 consecutive days, 10 mg/kg, s.c.). Micro-PET with 4-[(18)F]-ADAM was performed on days 4, 10, 17, 24, and 31. In addition, the time course of occupancy by fluoxetine at 4-[(18)F]-ADAM sites was measured. Specific 4-[(18)F]-ADAM uptake ratios (SURs) were calculated from the micro-PET imaging data for various brain regions. Immunohistochemistry was performed 7 days after the last micro-PET scan. From day 4 to day 31, SURs were markedly decreased (by approximately 55-75% compared to control values) in all brain regions in MDMA-treated rats. The effect of MDMA was markedly attenuated (approximately 30-50%) by fluoxetine. The fluoxetine-induced decrease in uptake in different brain regions was 40-75% at 90-min postinjection, and this decrease returned to baseline values in most brain regions by day 31. The distribution and intensity of serotonin transporter (SERT) immunostaining in the brain paralleled the PET imaging results, suggesting that a single dose of fluoxetine provides long-lasting protection against MDMA-induced loss of SERT and that such neuroprotection is detectable in vivo by 4-[(18)F]-ADAM micro-PET.