Fibromyalgia Pathogenesis and Treatment Options Update

This review article presents and summarizes up-to-date literature on the clinical manifestations, diagnosis, pathophysiological mechanisms, and treatment options for fibromyalgia patients. First, the most recent diagnostic criteria for fibromyalgia, as put forth by the American College of Rheumatology will be summarized. Clinical features, including chronic widespread pain, hyperalgesia, mood disorders, anxiety, and disturbed sleep patterns will be explored in-depth. The pathogenesis and pathophysiology of fibromyalgia involves alterations in multiple ascending and descending central nervous system pathways, as well as peripheral pathways, leading to heightened pain sensitivity. Risk factors have been studied extensively, and the most recent research focuses on various genetic influences and the contributions of stress and poor sleep. Lastly, the discussion in this article focuses on treatment options for fibromyalgia; some have been mainstay options for many years. Pharmacological agents include tricyclic antidepressants, anti-epileptic drugs, selective serotonin reuptake inhibitors, norepinephrine/serotonin reuptake inhibitors, as well as some investigational agents. The evidence behind non-pharmacologic treatments, including massage therapy, exercise, and acupuncture, are discussed.     

Targeting the Human Cerebellum with Transcranial Direct Current Stimulation to Modulate Behavior: a Meta-Analysis

Transcranial direct current stimulation (tDCS) is increasingly used to study motor- and non-motor-related functions of the cerebellum. The aim of the present study was to quantitatively review available studies to estimate the efficacy of cerebellar tDCS in altering motor- and cognitive-related behavioral performance in healthy volunteers. The present meta-analysis included 32 sham-controlled studies. Results from random effects modeling of the cumulative effect size demonstrated that anodal and cathodal tDCS to the cerebellum were effective in changing performance. No evidence for polarity-dependent effects of cerebellar tDCS was found. Current findings establish the feasibility to target motor and non-motor-related cerebellar functions with tDCS, but arguably due to anatomical differences between the cerebellum and cerebral cortex, the polarity of tDCS is not predictive of the direction of the behavioral changes in healthy volunteers.     

Modulation of Binge-like Ethanol Consumption by IL-10 Signaling in the Basolateral Amygdala

Excessive ethanol consumption alters the neuroimmune system and particularly impacts the cytokine milieu of the CNS. Cytokine dysregulation has been shown to underlie addictive-like behaviors including alcohol abuse; however, many studies focus primarily on the proinflammatory cytokine profile during alcohol dependence. The current study furthers this research by determining the impact of excessive ethanol consumption on interleukin-10 (IL-10) and interleukin-4 (IL-4) activity in a model of non-dependent binge consumption called the “drinking in the dark” (DID) paradigm. Furthermore, the ability of IL-10 to modulate ethanol consumption was tested using site-directed pharmacology. Immunohistochemistry analyses determined that ethanol decreased IL-10 by 50 % in the basolateral amygdala (BLA) but had no effect on IL-4. Neither IL-10 nor IL-4, however, were altered in the central amygdala (CEA). Enzyme linked immunosorbent assays confirmed that IL-10 was decreased in the amygdala but not in the serum, suggesting changes of this cytokine with the DID paradigm are restricted to the central nervous system. Finally, bilateral infusions of IL-10 into the BLA, but not CeA, reduced binge-like drinking and corresponding blood ethanol concentrations without impacting either locomotor activity or anxiety-like behavioral correlates. Together, these data support the idea that alcohol abuse dysregulates specific anti-inflammatory cytokines; however, ameliorating alcohol-induced effects on cytokines, like IL-10, may prove to be an effective therapy in curbing excessive consumption.     

Evaluation of transcutaneous and end-tidal carbon dioxide levels during inhalation sedation in volunteers

Measurement of end-tidal carbon dioxide (P_ETCO₂) is useful because of its noninvasiveness, continuity, and response time when sudden changes in ventilation occur during inhalation sedation. We compared the accuracy of P_ETCO₂ using a nasal mask and nasal cannula with the accuracy of transcutaneous carbon dioxide (TC-CO₂) and determined which method is more useful during inhalation sedation in volunteers. We used a modified nasal mask (MNM) and modified nasal cannula (MNC) for measurement of P_ETCO₂. The capnometer measured P_ETCO₂ in the gas expired from the nasal cavity by means of two devices. The volunteers received supplemental O₂ by means of each device at a flow rate of 6 L/min. After the volunteers lay quietly for 5 min with a supply of 100 % O₂, they received supplemental N₂O by means of each device at concentrations of 10, 20, and 25 % for 5 min and 30 % for 25 min. The correlation coefficient was poorer in the MNM than in the MNC, and the mean difference between TC-CO₂ and P_ETCO₂ in the MNM was greater than that in the MNC. The difference between the TC-CO₂ and P_ETCO₂ ranged from 3 to 6 mmHg in the MNM and from 2 to 5 mmHg in the MNC. The difference between two variables against the TC-CO₂ and the CO₂ waveforms obtained by means of the two devices were within the clinically acceptable range. Our two devices can provide continuous monitoring of P_ETCO₂ with a supply of N₂O/O₂ in patients undergoing inhalation sedation.