Lipocalin-2 activates hepatic stellate cells and promotes nonalcoholic steatohepatitis in high-fat diet-fed Ob/Ob mice.

BACKGROUND AND AIMS: In obesity and type 2 diabetes mellitus, leptin promotes insulin resistance and contributes to the progression of NASH via activation of hepatic stellate cells (HSCs). However, the pathogenic mechanisms that trigger HSC activation in leptin-deficient obesity are still unknown. This study aimed to determine how HSC-targeting lipocalin-2 (LCN2) mediates the transition from simple steatosis to NASH. APPROACH AND RESULTS: Male wild-type (WT) and ob/ob mice were fed a high-fat diet (HFD) for 20 weeks to establish an animal model of NASH with fibrosis. Ob/ob mice were subject to caloric restriction or recombinant leptin treatment. Double knockout (DKO) mice lacking both leptin and lcn2 were also fed an HFD for 20 weeks. In addition, HFD-fed ob/ob mice were treated with gadolinium trichloride to deplete Kupffer cells. The LX-2 human HSCs and primary HSCs from ob/ob mice were used to investigate the effects of LCN2 on HSC activation. Serum and hepatic LCN2 expression levels were prominently increased in HFD-fed ob/ob mice compared with normal diet-fed ob/ob mice or HFD-fed WT mice, and these changes were closely linked to liver fibrosis and increased hepatic α-SMA/matrix metalloproteinase 9 (MMP9)/signal transducer and activator of transcription 3 (STAT3) protein levels. HFD-fed DKO mice showed a marked reduction of α-SMA protein compared with HFD-fed ob/ob mice. In particular, the colocalization of LCN2 and α-SMA was increased in HSCs from HFD-fed ob/ob mice. In primary HSCs from ob/ob mice, exogenous LCN2 treatment induced HSC activation and MMP9 secretion. By contrast, LCN2 receptor 24p3R deficiency or a STAT3 inhibitor reduced the activation and migration of primary HSCs. CONCLUSIONS: LCN2 acts as a key mediator of HSC activation in leptin-deficient obesity via α-SMA/MMP9/STAT3 signaling, thereby exacerbating NASH.

Prediction model for mild cognitive impairment in patients with type 2 diabetes using the autonomic function test.

OBJECTIVE: Type 2 diabetes mellitus (T2DM) is a risk factor for cognitive impairment, and reduced heart rate variability (HRV) has been correlated with cognitive impairment in elderly individuals. This study investigated risk factors and validated a predictive model for mild cognitive impairment (MCI) in patients with T2DM using an autonomic function test. METHODS: Patients with T2DM, 50-85 years of age, who attended the diabetes clinic at Gyeongsang National University Hospital between March 2018 and December 2019, were included. A total of 201 patients had been screened; we enrolled 124 patients according to the inclusion and exclusion criteria in this study. Cognitive function was assessed using the Montreal Cognitive Assessment-Korean version (MOCA-K); MCI was defined as a total MOCA-K score ≤ 23. Risk factors for MCI in patients with T2DM, including demographic- and diabetes-related factors, and autonomic function test results, were analyzed. Based on multivariate logistic regression, a nomogram was developed as a prediction model for MCI. RESULTS: Thirty-nine of 124 patients were diagnosed with MCI. Age, education, and decreased cardiovagal function were associated with a high risk for MCI, with cardiovagal function exerting the greatest influence. However, diabetes-related factors, such as glycemic control, duration of diabetes, or medications, were not associated with the risk for MCI. The nomogram demonstrated excellent discrimination (area under the curve, 0.832) and was well calibrated. CONCLUSION: Approximately one-third of patients had MCI; as such, carefully evaluating cognitive function in elderly T2DM patients with reduced HRV is important to prevent progression to dementia.

The Perceived Value of Same-Sex or Same-Race Mentors and Role Models in Academic Medicine.

This study aims to describe the perception of need for same-sex and same-race mentorship and role models at evolving stages of a medical career and to explore whether these differences affect career choices within the field of medicine. A total of 326 medical students, 309 resident physicians, and 200 faculty attending physicians at the University of California, Davis School of Medicine completed an online survey focused on their perceived value of same-sex and same-race mentorship throughout their stages of medical training and practice. The top three factors influencing specialty choice were lifestyle, time commitment, and supportive department. Although most respondents did not believe same-sex or same-race mentors or role models influenced their specialty choice, there were significant differences in the perceived importance and value of gender or race concordance between male versus female and white versus nonwhite populations. (Journal of Surgical Orthopaedic Advances 33(1):041-048, 2024).

Treatment pattern and response for cluster headache in Korea: A prospective multicenter observation study.

BACKGROUND: Only limited data are available regarding the treatment status and response to cluster headache in an Asian population. Therefore, this study aimed to provide a real-world treatment pattern of cluster headache and the response rate of each treatment in an Asian population. METHODS: Patients with cluster headache were recruited between September 2016 and January 2019 from 16 hospitals in Korea. At the baseline visit, we surveyed the patients about their previous experience of cluster headache treatment, and acute and/or preventive treatments were prescribed at the physician's discretion. Treatment response was prospectively evaluated using a structured case-report form at 2 ± 2 weeks after baseline visit and reassessed after three months. RESULTS: Among 295 recruited patients, 262 experiencing active bouts were included. Only one-third of patients reported a previous experience of evidence-based treatment. At the baseline visit, oral triptans (73.4%), verapamil (68.3%), and systemic steroids (55.6%) were the three most common treatments prescribed by the investigators. Most treatments were given as combination. For acute treatment, oral triptans and oxygen were effective in 90.1% and 86.8% of the patients, respectively; for preventive treatment, evidence-based treatments, i.e. monotherapy or different combinations of verapamil, lithium, systemic steroids, and suboccipital steroid injection, helped 75.0% to 91.8% of patients. CONCLUSION: Our data provide the first prospective analysis of treatment responses in an Asian population with cluster headache. The patients responded well to treatment despite the limited availability of treatment options, and this might be attributed at least in part by combination of medications. Most patients were previously undertreated, suggesting a need to raise awareness of cluster headache among primary physicians.

c-di-GMP inhibits LonA-dependent proteolysis of TfoY in Vibrio cholerae.

The LonA (or Lon) protease is a central post-translational regulator in diverse bacterial species. In Vibrio cholerae, LonA regulates a broad range of behaviors including cell division, biofilm formation, flagellar motility, c-di-GMP levels, the type VI secretion system (T6SS), virulence gene expression, and host colonization. Despite LonA's role in cellular processes critical for V. cholerae's aquatic and infectious life cycles, relatively few LonA substrates have been identified. LonA protease substrates were therefore identified through comparison of the proteomes of wild-type and ΔlonA strains following translational inhibition. The most significantly enriched LonA-dependent protein was TfoY, a known regulator of motility and the T6SS in V. cholerae. Experiments showed that TfoY was required for LonA-mediated repression of motility and T6SS-dependent killing. In addition, TfoY was stabilized under high c-di-GMP conditions and biochemical analysis determined direct binding of c-di-GMP to LonA results in inhibition of its protease activity. The work presented here adds to the list of LonA substrates, identifies LonA as a c-di-GMP receptor, demonstrates that c-di-GMP regulates LonA activity and TfoY protein stability, and helps elucidate the mechanisms by which LonA controls important V. cholerae behaviors.

Efficacy of Intravenous Mesenchymal Stem Cells for Motor Recovery After Ischemic Stroke: A Neuroimaging Study.

BACKGROUND AND PURPOSE: Stem cell-based therapy is a promising approach to repair brain damage after stroke. This study was conducted to investigate changes in neuroimaging measures using stem cell-based therapy in patients with ischemic stroke. METHODS: In this prospective, open-label, randomized controlled trial with blinded outcome evaluation, patients with severe middle cerebral artery territory infarct were assigned to the autologous mesenchymal stem cell (MSC) treatment or control group. Of 54 patients who completed the intervention, 31 for the MSC and 13 for the control groups were included in this neuroimaging analysis. Motor function was assessed before the intervention and 90 days after randomization using the Fugl-Meyer assessment scale. Neuroimaging measures included fractional anisotropy values of the corticospinal tract and posterior limb of the internal capsule from diffusion tensor magnetic resonance imaging and strength of connectivity, efficiency, and density of the motor network from resting-state functional magnetic resonance imaging. RESULTS: For motor function, the improvement ratio of the Fugl-Meyer assessment score was significantly higher in the MSC group compared with the control group. In neuroimaging, corticospinal tract and posterior limb of the internal capsule fractional anisotropy did not decrease in the MSC group but significantly decreased at 90 days after randomization in the control group. Interhemispheric connectivity and ipsilesional connectivity significantly increased in the MSC group. Change in interhemispheric connectivity showed a significant group difference. CONCLUSIONS: Stem cell-based therapy can protect corticospinal tract against degeneration and enhance positive changes in network reorganization to facilitate motor recovery after stroke. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01716481.

Health and economic impact of a smoking cessation program in Korean workplaces.

Smoking is a leading cause of diseases and death, with significant socioeconomic consequences. The purpose of this study was to evaluate the health and economic effectiveness of a workplace smoking cessation program. A total of 89 smokers from seven workplaces in Korea were the participants of the program. For 4 months, individual counseling based on the transtheoretical model (TTM) was conducted and interpersonal and organizational components were applied to encourage entire workplaces to encourage employee smoking cessation. The primary outcome was whether participants quit smoking or not. We also evaluated the changes in attitude and perceptions related to smoking cessation before and after the program and estimated the program's economic effects. Economic effects were defined as reductions in productivity losses and medical expenses. We calculated the return on investment (ROI) values representing the averted cost through the program compared to program cost. At the end of the program, 40.4% of participants quit smoking. Improvements were observed in TTM-based attitudes and perceptions. The mean reduction in productivity losses was estimated to be $187,609.94 for 2 yr and the mean reduction in medical expenses was $3,136.49 at 20 yr among seven workplaces. When accounting for these reductions, the ROI was 15.39 (ranging from -1.00 to 44.53). These effects were robust under various scenarios. The smoking cessation program should be expanded to a wider variety of workplaces. In the future, more sophisticated economic assessment methods should be developed and applied to facilitate workplace recruitment and attract management support.

Smoking is a major cause of disease and death with large socioeconomic costs. This study examined the effect of a workplace smoking cessation program on health perspective, and on productivity and profit. A total of 40.4% of participants quit smoking, and the perceptions on smoking were improved. Also, the program was revealed to have an average return on investment (ROI) of 15.39. This can be deemed as the program's economic effect is 15.39 times the program cost. We believe this kind of evaluation may help with the dissemination of workplace health promotion programs.

Structural aberrations of the brain associated with migraine: A narrative review.

OBJECTIVE: To summarize major results from imaging studies investigating brain structure in migraine. BACKGROUND: Neuroimaging studies, using several different imaging and analysis techniques, have demonstrated aberrations in brain structure associated with migraine. This narrative review summarizes key imaging findings and relates imaging findings with clinical features of migraine. METHODS: We searched PubMed for English language articles using the key words "neuroimaging" AND/OR "MRI" combined with "migraine" through August 20, 2020. The titles and abstracts of resulting articles were reviewed for their possible inclusion in this manuscript, followed by examination of the full texts and reference lists of relevant articles. RESULTS: Migraine is associated with structural brain aberrations within regions that participate in pain processing, the processing of other sensory stimuli, multisensory integration, and in white matter fiber tracts. Furthermore, migraine is associated with magnetic resonance imaging T2/fluid-attenuated inversion recovery white matter hyperintensities. Some structural aberrations are correlated with the severity and clinical features of migraine, whereas others are not. These findings suggest that some structural abnormalities are associated with or amplified by recurrent migraine attacks, whereas others are intrinsic to the migraine brain. CONCLUSIONS: Migraine is associated with aberrant brain structure. Structural neuroimaging studies contribute to understanding migraine pathophysiology and identification of brain regions associated with migraine and its individual symptoms. Additional work is needed to determine the extent to which structural aberrations are a result of recurrent migraine attacks, and perhaps reversible with effective treatment or migraine resolution, versus being intrinsic traits of the migraine brain.

The Effect of Auricular Acupressure for Chronic Low Back Pain in Elders: A Randomized Controlled Study.

Chronic low back pain (CLBP) is a major problem throughout the world and getting worse because of population increase and aging. The cost of treatment increases as the population of people with CLBP increases. This study aimed to examine the effect of auricular acupressure (AA) on pain and disability in elders with chronic low back pain. The randomized, single-blinded, and placebo-controlled study was conducted on 51 elders with CLBP in South Korea from June 2019 to August 2019. The experimental group (n = 26) received AA on low back pain-related points, whereas the placebo control group (n = 25) received AA on points unrelated to low back pain. Participants received 6 weeks of AA in weekly cycles. Collected data were analyzed using IBM SPSS Statistics, version 25. Statistically significant differences between the 2 groups emerged in the visual analog scale (P < .001), pain threshold (P < .001), and Oswestry Disability Index (P < .001). This study showed that 6 weeks of AA improved CLBP and pain-related disability. Therefore, AA can be used as a noninvasive and self-managed alternative intervention for CLBP in older adults.

Glucocorticoid-Induced Hypokalemic Periodic Paralysis after Short-Term Use of Tenofovir with Hypophosphatemia: A Case Report.

Hypokalemic periodic paralysis (HPP) is a neuromuscular disorder associated with muscular dysfunction caused by hypokalemia. There are various causes of HPPs and rarely, HPP appears to be relevant to tenofovir or glucocorticoid treatment. There have been several case reports of tenofovir-related nephrotoxicity or tenofovir-induced HPP. However, a case report of glucocorticoid-induced HPP in a patient using tenofovir temporarily has not been reported. Herein, we report a case of glucocorticoid-induced HPP with short-term use of tenofovir. A 28-year-old man visited the emergency room with decreased muscle power in all extremities (2/5 grade). In their past medical history, the patient was treated with tenofovir for two months for a hepatitis B virus infection. At the time of the visit, the drug had been discontinued for four months. The day before visiting the emergency room, betamethasone was administered at a local clinic for herpes on the lips. Laboratory tests showed hypokalemia, hypophosphatemia, and mild metabolic acidosis. However, urinalysis revealed no abnormal findings. Consequently, it can be postulated that this patient developed HPP by glucocorticoids after taking tenofovir temporarily. This is the first case report of glucocorticoid-induced HPP in a patient using tenofovir. Clinicians who prescribe tenofovir should be aware of HPP occurring when glucocorticoids are used.

Temporal changes of circadian rhythmicity in cluster headache.

OBJECTIVE: To investigate the temporal changes of circadian rhythmicity in relation to the disease course in patients with cluster headache. METHODS: In this multicenter study, patients with cluster headache were recruited between September 2016 and July 2018. We evaluated the patients for circadian rhythmicity and time of cluster headache attacks in the current bout and any experience of bout-to-bout change in circadian rhythmicity. We analyzed the patterns of circadian rhythmicity in relation to the disease progression (the number of total lifetime bouts, grouped into deciles). RESULTS: Of the 175 patients in their active, within-bout period, 86 (49.1%) had circadian rhythmicity in the current bout. The prevalence of circadian rhythmicity in the active period was overall similar regardless of disease progression. Sixty-three (46.3%) out of 136 patients with ≥2 bouts reported bout-to-bout changes in circadian rhythmicity. The most frequent time of cluster headache attacks was distributed evenly throughout the day earlier in the disease course and dichotomized into hypnic and midday as the number of lifetime bouts increased (p = 0.037 for the homogeneity of variance). When grouped into nighttime and daytime, nighttime attacks were predominant early in the disease course, while daytime attacks increased with disease progression (up to 7th deciles of total lifetime bouts, p = 0.001) and decreased in patients with the most advanced disease course (p = 0.013 for the non-linear association). CONCLUSIONS: Circadian rhythmicity is not a fixed factor, and changes according to the disease course. Our findings will be valuable in providing a new insight into the stability of functional involvement of the suprachiasmatic nucleus in the pathophysiology of cluster headache.

Protective Effects of Evogliptin on Steatohepatitis in High-Fat-Fed Mice.

There are few studies on the effects of dipeptidyl peptidase-4 inhibitors on steatohepatitis. We explored whether evogliptin (Evo), a dipeptidyl peptidase-4 inhibitor, protects against steatohepatitis in a high-fat diet (HFD)-fed mice and whether these effects involve modulation of mitophagy. Adult male C57BL/J mice were divided into the normal diet (ND), HFD (45% of energy from fat) with Evo (250 mg/kg) (HFD + Evo), and HFD groups at 4 weeks of age and were sacrificed at 20 weeks of age. The HFD group showed hepatic lipid accumulation; this was decreased in the Evo + HFD group. There was an increased 8-hydroxydeoxyguanosine (8-OHDG) expression in the HFD group compared to ND mice. However, 8-OHDG expression levels were significantly decreased in the HFD + Evo group. Expressions of the mitophagy markers PTEN-induced kinase 1 (PINK1), Parkin, and BNIP-3 (BCL2 Interacting Protein 3) were significantly increased in the HFD group. However, the expressions of these markers were lower in the HFD + Evo group than that in the HFD group. Phospho-Akt was upregulated and p53 was downregulated in the HFD + Evo group compared to the HFD group. Evogliptin may alleviate steatohepatitis in HFD-fed mice by ameliorating steatosis and oxidative stress and by modulating mitophagy in the liver.

Clinical correlates of insomnia in patients with persistent post-traumatic headache compared with migraine.

BACKGROUND: Close associations between insomnia with other clinical factors have been identified in migraine, but there have been few studies investigating associations between insomnia and clinical factors in patients with persistent post-traumatic headache (PPTH). The study objective was to contrast the severity of insomnia symptoms in PPTH, migraine, and healthy controls, and to identify factors associated with insomnia in patients with PPTH vs. migraine. METHODS: In this cross-sectional cohort study, 57 individuals with PPTH attributed to mild traumatic brain injury, 39 with migraine, and 39 healthy controls were included. Participants completed a detailed headache characteristics questionnaire, the Migraine Disability Assessment Scale (MIDAS), Insomnia Severity Index (ISI), Hyperacusis Questionnaire (HQ), Allodynia Symptom Checklist, Photosensitivity Assessment Questionnaire, Beck Depression Inventory (BDI), State-Trait Anxiety Inventory, Post-Traumatic Stress Disorder (PTSD) checklist, Ray Auditory Verbal Learning Test, and the Trail Making Test A and B to assess headache characteristics, disability, insomnia symptoms, sensory hypersensitivities, and neuropsychological factors. Fisher's test and one-way ANOVA or Tukey's Honest Significant Difference were used to assess group differences of categorical and continuous data. Stepwise linear regression analyses were conducted to identify clinical variables associated with insomnia symptoms. RESULTS: Those with PPTH had significantly higher ISI scores (16.7 ± 6.6) compared to migraine patients (11.3 ± 6.4) and healthy controls (4.1 ± 4.8) (p <  0.001). For those with PPTH, insomnia severity was most strongly correlated with the BDI (Spearman's rho (ρ) = 0.634, p <  0.01), followed by Trait Anxiety (ρ = 0.522, p <  0.01), PTSD (ρ = 0.505, p <  0.01), HQ (ρ = 0.469, p <  0.01), State Anxiety (ρ = 0.437, p <  0.01), and MIDAS scores (ρ = 0.364, p <  0.01). According to linear regression models, BDI, headache intensity, and hyperacusis scores were significantly positively associated with insomnia severity in those with PPTH, while only delayed memory recall was negatively associated with insomnia severity in those with migraine. CONCLUSIONS: Insomnia symptoms were more severe in those with PPTH compared to migraine and healthy control cohorts. Depression, headache intensity, and hyperacusis were associated with insomnia in individuals with PPTH. Future studies should determine the bidirectional impact of treating insomnia and its associated symptoms.

The impact of remission and coexisting migraine on anxiety and depression in cluster headache.

BACKGROUND: Our aim was to investigate the relationship between coexisting cluster headache (CH) and migraine with anxiety and depression during active cluster bouts, and how symptoms change during remission. METHODS: We analyzed data from 222 consecutive CH patients and 99 age- and sex-matched controls using a prospective multicenter registry. Anxiety or depression was evaluated using the Generalized Anxiety Disorder-7 (GAD-7) or Patient Health Questionnaire-9 (PHQ-9), respectively. Moderate-to-severe anxiety or depression was defined as a score of ≥10 at baseline (during a cluster bout). We assessed for changes in anxiety and depression during CH remission periods. RESULTS: Among the CH patients, the prevalence of moderate-to-severe anxiety and depression was seen in 38.2% and 34.6%, respectively. Compared with controls, CH patients were associated with moderate-to-severe anxiety and depression (multivariable-adjusted odds ratio [aOR] = 7.32, 95% confidence intervals [CI] = 3.35-15.99 and aOR = 4.95, 95% CI = 2.32-10.57, respectively). CH patients with migraine were significantly more likely to have moderate-to-severe anxiety and depression (aOR = 32.53, 95% CI = 6.63-159.64 and aOR = 16.88, 95% CI = 4.16-68.38, respectively), compared to controls without migraine. The GAD-7 and PHQ-9 scores were significantly reduced between cluster bout and remission periods (from 6.8 ± 5.6 to 1.6 ± 2.8; P < 0.001, and from 6.1 ± 5.0 to 1.8 ± 2.4; P < 0.001, respectively). CONCLUSIONS: Our results indicate that CH patients are at increased risk of anxiety and depression, especially in the presence of coexisting migraine. However, the anxiety and depression can improve during remission periods.

Field testing the diagnostic criteria of cluster headache in the third edition of the International Classification of Headache Disorders: A cross-sectional multicentre study.

BACKGROUND: *These authors are shared first authors. The recently published third edition of the International Classification of Headache Disorders (ICHD-3) revised the criteria for accompanying symptoms of cluster headache (CH) and the remission period of chronic cluster headache (CCH). This study aimed at testing the validity of the ICHD-3 criteria for CH by using data from the Korean Cluster Headache Registry. METHODS: Consecutive patients with CH and probable cluster headache (PCH) were prospectively recruited from 15 hospitals. We analysed the validity of the revised ICHD-3 criteria for CH against the beta version of the third edition of the ICHD (ICHD-3ß). RESULTS: In total, 193 patients were enrolled: 140 (72.5%), 5 (2.6%) and 22 (11.4%) had episodic cluster headache (ECH), CCH, and PCH, respectively. The remaining 26 (13.5%) had CH with undetermined remission periods. One patient with ECH and one with PCH had only forehead and facial flushing and were diagnosed with PCH and non-cluster headache, respectively, according to the ICHD-3. Four participants with ECH according to the ICHD-3ß had remission periods of > 1 month and between 1 and 3 months and were newly diagnosed with CCH according to the ICHD-3. CONCLUSION: The change from ICHD-3ß to ICHD-3 resulted in few differences in the diagnoses of CH and PCH.

Increased suicidality in patients with cluster headache.

OBJECTIVE: To investigate suicidality related to cluster headache and factors associated with increased suicidality in cluster headache patients. METHODS: In this multicenter study, 193 cluster headache patients were recruited between September 2016 and August 2018. Patients were asked about their suicidality during and between attacks, specifically about passive suicidal ideation, active suicidal ideation, suicide plan, and suicide attempt. Univariable and multivariable logistic regression analyses were performed to evaluate the factors associated with high ictal suicidality (sum of positive response ≥ 2). Patients were followed up when they were in the between-bouts period. RESULTS: A total of 175 cluster headache patients in the in-bout period were included in this study. Passive suicidal ideation, active suicidal ideation, suicidal planning, and suicidal attempt were reported by 111 (64.2%), 62 (35.8%), 10 (5.8%), and four (2.3%) patients during attacks; seven (4.0%), six (3.5%), five (2.9%) and two (1.2%) patients interictally; and none (0%), one (1.9%), one (1.9%), and none (0%) among patients in the between-bouts period. Factors associated with high ictal suicidality were longer disease duration, the Headache Impact Test score, and the Patient Health Question-9 score (multivariable OR = 1.90 per 10-year increase in disease duration, 95% CI = 1.18-3.05, p = 0.008; multivariable OR = 3.19 per 10-point increase in HIT-6, 95% CI = 1.73-5.87, p < 0.001; multivariable OR = 2.11 per 10-point increase in PHQ-9, 95% CI = 1.13-3.95, p = 0.020, respectively). CONCLUSIONS: Cluster headache attack carries a high suicidality compared to the interictal or between-bouts state. An intensive treatment to reduce cluster headache burden may be helpful to alleviate suicide risk in cluster headache patients.

Differences of Cluster Headache on the Basis of Sex in the Korean Cluster Headache Registry.

BACKGROUND: Most of the clinical characteristics of cluster headache (CH) have been established through the observation of men with CH. Epidemiological data of CH in women are scarce especially in the Asian population. Here, we sought to assess the prevalence and clinical characteristics of women with CH in comparison to men in a prospective CH registry. METHODS: Data used in this study were obtained from the Korean Cluster Headache Registry, a prospective, cross-sectional, multicenter headache registry that collected data from consecutive patients diagnosed with CH. Demographics and clinical characteristics were compared between the sexes. RESULTS: In total, 250 patients were enrolled in this study; 41 (16.4%) were women (male to female ratio 5.1:1). Mean age of onset did not differ between women and men (30.7 ± 15.5 vs 29.0 ± 11.1 years). The clinical features of CH in women and men were similar, with no differences in pain severity, duration, and attack frequency. Among autonomic features, facial and forehead sweating was significantly rare in women (4.9%) compared to men with CH (33.0%). Headache-related disability assessed by Headache Impact Test-6 did not differ between the sexes; however, depression scale assessed by Patients Health Questionnaire-9 (11.0 ± 8.5 vs 7.0 ± 5.8, P = .009) and stress (Perceived Stress Scale 4, 7.5 ± 3.4 vs 6.4 ± 3.0, P = .045) were significantly higher in women with CH. CONCLUSIONS: Although decreasing male preponderance was suggested in recent Western CH studies, CH in women is still far less prevalent than in men in the Korean population. Clinical and demographic characteristics were similar between the sexes. However, psychiatric comorbidities might be highly associated in women with CH.

A Subset of Exoribonucleases Serve as Degradative Enzymes for pGpG in c-di-GMP Signaling.

Bis-(3'-5')-cyclic dimeric GMP (c-di-GMP) is a bacterial second messenger that regulates processes, such as biofilm formation and virulence. During degradation, c-di-GMP is first linearized to 5'-phosphoguanylyl-(3',5')-guanosine (pGpG) and subsequently hydrolyzed to two GMPs by a previously unknown enzyme, which was recently identified in Pseudomonas aeruginosa as the 3'-to-5' exoribonuclease oligoribonuclease (Orn). Mutants of orn accumulated pGpG, which inhibited the linearization of c-di-GMP. This product inhibition led to elevated c-di-GMP levels, resulting in increased aggregate and biofilm formation. Thus, the hydrolysis of pGpG is crucial to the maintenance of c-di-GMP homeostasis. How species that utilize c-di-GMP signaling but lack an orn ortholog hydrolyze pGpG remains unknown. Because Orn is an exoribonuclease, we asked whether pGpG hydrolysis can be carried out by genes that encode protein domains found in exoribonucleases. From a screen of these genes from Vibrio cholerae and Bacillus anthracis, we found that only enzymes known to cleave oligoribonucleotides (orn and nrnA) rescued the P. aeruginosa Δorn mutant phenotypes to the wild type. Thus, we tested additional RNases with demonstrated activity against short oligoribonucleotides. These experiments show that only exoribonucleases previously reported to degrade short RNAs (nrnA, nrnB, nrnC, and orn) can also hydrolyze pGpG. A B. subtilisnrnA nrnB mutant had elevated c-di-GMP, suggesting that these two genes serve as the primary enzymes to degrade pGpG. These results indicate that the requirement for pGpG hydrolysis to complete c-di-GMP signaling is conserved across species. The final steps of RNA turnover and c-di-GMP turnover appear to converge at a subset of RNases specific for short oligoribonucleotides.IMPORTANCE The bacterial bis-(3'-5')-cyclic dimeric GMP (c-di-GMP) signaling molecule regulates complex processes, such as biofilm formation. c-di-GMP is degraded in two-steps, linearization into pGpG and subsequent cleavage to two GMPs. The 3'-to-5' exonuclease oligoribonuclease (Orn) serves as the enzyme that degrades pGpG in Pseudomonas aeruginosa Many phyla contain species that utilize c-di-GMP signaling but lack an Orn homolog, and the protein that functions to degrade pGpG remains uncharacterized. Here, systematic screening of genes encoding proteins containing domains found in exoribonucleases revealed a subset of genes encoded within the genomes of Bacillus anthracis and Vibrio cholerae that degrade pGpG to GMP and are functionally analogous to Orn. Feedback inhibition by pGpG is a conserved process, as strains lacking these genes accumulate c-di-GMP.

Bacterial ornithine lipid, a surrogate membrane lipid under phosphate-limiting conditions, plays important roles in bacterial persistence and interaction with host.

Ornithine lipids (OLs) are bacteria-specific lipids that are found in the outer membrane of Gram (-) bacteria and increase as surrogates of phospholipids under phosphate-limited environmental conditions. We investigated the effects of OL increase in bacterial membranes on pathogen virulence and the host immune response. In Pseudomonas aeruginosa, we increased OL levels in membranes by overexpressing the OL-synthesizing operon (olsBA). These increases changed the bacterial surface charge and hydrophobicity, which reduced bacterial susceptibility to antibiotics and antimicrobial peptides (AMPs), interfered with the binding of macrophages to bacterial cells and enhanced bacterial biofilm formation. When grown under low phosphate conditions, P. aeruginosa became more persistent in the treatment of antibiotics and AMPs in an olsBA-dependent manner. While OLs increased persistence, they attenuated P. aeruginosa virulence; in host cells, they reduced the production of inflammatory factors (iNOS, COX-2, PGE2 and nitric oxide) and increased intracellular Ca2+ release. Exogenously added OL had similar effects on P. aeruginosa and host cells. Our results suggest that bacterial OL plays important roles in bacteria-host interaction in a way that enhances bacterial persistence and develops chronic adaptation to infection.

Impact of cluster headache on employment status and job burden: a prospective cross-sectional multicenter study.

BACKGROUND: Cluster headaches (CH) are recurrent severe headaches, which impose a major burden on the life of patients. We investigated the impact of CH on employment status and job burden. METHODS: The study was a sub-study of the Korean Cluster Headache Registry. Patients with CH were enrolled from September 2016 to February 2018 from 15 headache clinics in Korea. We also enrolled a headache control group with age-sex matched patients with migraine or tension-type headache. Moreover, a control group including individuals without headache complaints was recruited. All participants responded to a questionnaire that included questions on employment status, type of occupation, working time, sick leave, reductions in productivity, and satisfaction with current occupation. The questionnaire was administered to participants who were currently employed or had previous occupational experience. RESULTS: We recruited 143 patients with CH, 38 patients with other types of headache (migraine or tension-type headache), and 52 headache-free controls. The proportion of employees was lower in the CH group compared with the headache and headache-free control groups (CH: 67.6% vs. headache controls: 84.2% vs. headache-free controls: 96.2%; p = 0.001). The CH group more frequently experienced difficulties at work and required sick leave than the other groups (CH: 84.8% vs. headache controls: 63.9% vs. headache-free controls: 36.5%; p <  0.001; CH: 39.4% vs. headache controls: 13.9% vs. headache-free controls: 3.4%; p <  0.001). Among the patients with CH, sick leave was associated with younger age at CH onset (25.8 years vs. 30.6 years, p = 0.014), severity of pain rated on a visual analogue scale (9.3 vs. 8.8, p = 0.008), and diurnal periodicity during the daytime (p = 0.003). There were no significant differences with respect to the sick leave based on sex, age, CH subtypes, and CH recurrence. CONCLUSIONS: CH might be associated with employment status. Most patients with CH experienced substantial burdens at work.