Acute Effects and the Dreamy State Evoked by Deep Brain Electrical Stimulation of the Amygdala: Associations of the Amygdala in Human Dreaming, Consciousness, Emotions, and Creativity.

Accurate localization of complex human experiences such as emotions, dreaming, creativity, and consciousness to specific cerebral structures or neural networks has remained elusive despite technological advances. We report the use of acute deep brain stimulation (DBS) to evoke behavioral and emotional effects by applying electrical stimulation (ES) at various voltage strengths to the basolateral and central subnuclei of the amygdala in addition to the head of hippocampus (HC) for two subjects with medically refractory post-traumatic stress disorder (PTSD). Our results suggest that the amygdala could be a node in a neural network responsible for the generation of complex vivid mental imagery and integrated sensory experiences similar to John Hughlings Jackson's "dreamy state" and "double consciousness," which have been classically associated with temporal lobe epilepsy during uncinate seizures. That we were able to elicit similar vivid, dynamic, complex, bizarre, and original mental imagery with ES in non-epileptic subjects suggests that Jackson's seizure related "dreamy state" and "double consciousness" may arise from heightened innate brain mechanisms with the amygdala acting as a node in the neural network responsible for physiologic dreaming and creative functions. Furthermore, our subjects experienced different emotions with different stimulation strengths at various electrode contacts. Our results suggest that higher voltage stimulation of the amygdala and HC at 4-5 V leads to predominantly negative responses and 2-4 V stimulation showed inversely coupled positive and negative responses of the amygdala in either hemisphere which may imply hemispheric dominance of emotional valences without relation to handedness. Due to the unique and complex responses dependent on location and strength of stimulation, we advise that all patients receiving DBS of the amygdala undergo acute stimulation mapping in a monitored setting before selecting therapeutic parameters for chronic stimulation.

Correcting glucose-6-phosphate dehydrogenase deficiency with a small-molecule activator.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency, one of the most common human genetic enzymopathies, is caused by over 160 different point mutations and contributes to the severity of many acute and chronic diseases associated with oxidative stress, including hemolytic anemia and bilirubin-induced neurological damage particularly in newborns. As no medications are available to treat G6PD deficiency, here we seek to identify a small molecule that corrects it. Crystallographic study and mutagenesis analysis identify the structural and functional defect of one common mutant (Canton, R459L). Using high-throughput screening, we subsequently identify AG1, a small molecule that increases the activity of the wild-type, the Canton mutant and several other common G6PD mutants. AG1 reduces oxidative stress in cells and zebrafish. Furthermore, AG1 decreases chloroquine- or diamide-induced oxidative stress in human erythrocytes. Our study suggests that a pharmacological agent, of which AG1 may be a lead, will likely alleviate the challenges associated with G6PD deficiency.

Randomized Embolization Trial for NeuroEndocrine Tumor Metastases to the Liver (RETNET): study protocol for a randomized controlled trial.

BACKGROUND: Neuroendocrine tumors (NETs) are the second most common gastrointestinal malignancy after colon cancer. Up to 90% of patients with NETs develop liver metastases, which are a major determinant of symptoms and survival. Current guidelines recommend embolotherapy for progressive or symptomatic NET liver metastases, but the optimal technique among bland embolization, lipiodol chemoembolization, and drug-eluting bead chemoembolization remains unknown and controversial. METHODS/DESIGN: A prospective, open-label, multicenter randomized controlled trial will be conducted in patients with progressive or symptomatic unresectable NET liver metastases. Patients will be randomized to treatment with bland embolization, lipiodol chemoembolization, or drug-eluting microsphere chemoembolization, with 60 enrollees per arm. The primary endpoint will be hepatic progression-free survival (HPFS) following initial embolotherapy by RECIST criteria. The sample size is powered to detect an HR of 1.78 for HPFS following chemoembolization compared with bland embolization, which was estimated on the basis of existing retrospective studies. Secondary endpoints include overall progression-free survival, duration of symptom control, quality of life, rate of adverse events, and interval between embolotherapy cycles. Interim safety analyses will be performed at 10 and 30 patients per arm. DISCUSSION: The RETNET trial is a prospective, multicenter randomized controlled trial designed to determine the optimal embolotherapy technique for NET liver metastases. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02724540 . Registered on March 31, 2016.

Opsin 3 and 4 mediate light-induced pulmonary vasorelaxation that is potentiated by G protein-coupled receptor kinase 2 inhibition.

We recently demonstrated that blue light induces vasorelaxation in the systemic mouse circulation, a phenomenon mediated by the nonvisual G protein-coupled receptor melanopsin (Opsin 4; Opn4). Here we tested the hypothesis that nonvisual opsins mediate photorelaxation in the pulmonary circulation. We discovered Opsin 3 (Opn3), Opn4, and G protein-coupled receptor kinase 2 (GRK2) in rat pulmonary arteries (PAs) and in pulmonary arterial smooth muscle cells (PASMCs), where the opsins interact directly with GRK2, as demonstrated with a proximity ligation assay. Light elicited an intensity-dependent relaxation of PAs preconstricted with phenylephrine (PE), with a maximum response between 400 and 460 nm (blue light). Wavelength-specific photorelaxation was attenuated in PAs from Opn4-/- mice and further reduced following shRNA-mediated knockdown of Opn3. Inhibition of GRK2 amplified the response and prevented physiological desensitization to repeated light exposure. Blue light also prevented PE-induced constriction in isolated PAs, decreased basal tone, ablated PE-induced single-cell contraction of PASMCs, and reversed PE-induced depolarization in PASMCs when GRK2 was inhibited. The photorelaxation response was modulated by soluble guanylyl cyclase but not by protein kinase G or nitric oxide. Most importantly, blue light induced significant vasorelaxation of PAs from rats with chronic pulmonary hypertension and effectively lowered pulmonary arterial pressure in isolated intact perfused rat lungs subjected to acute hypoxia. These findings show that functional Opn3 and Opn4 in PAs represent an endogenous "optogenetic system" that mediates photorelaxation in the pulmonary vasculature. Phototherapy in conjunction with GRK2 inhibition could therefore provide an alternative treatment strategy for pulmonary vasoconstrictive disorders.

Icebergs not the trigger for North Atlantic cold events.

Abrupt climate change is a ubiquitous feature of the Late Pleistocene epoch. In particular, the sequence of Dansgaard-Oeschger events (repeated transitions between warm interstadial and cold stadial conditions), as recorded by ice cores in Greenland, are thought to be linked to changes in the mode of overturning circulation in the Atlantic Ocean. Moreover, the observed correspondence between North Atlantic cold events and increased iceberg calving and dispersal from ice sheets surrounding the North Atlantic has inspired many ocean and climate modelling studies that make use of freshwater forcing scenarios to simulate abrupt change across the North Atlantic region and beyond. On the other hand, previous studies identified an apparent lag between North Atlantic cooling events and the appearance of ice-rafted debris over the last glacial cycle, leading to the hypothesis that iceberg discharge may be a consequence of stadial conditions rather than the cause. Here we further establish this relationship and demonstrate a systematic delay between pronounced surface cooling and the arrival of ice-rafted debris at a site southwest of Iceland over the past four glacial cycles, implying that in general icebergs arrived too late to have triggered cooling. Instead we suggest that--on the basis of our comparisons of ice-rafted debris and polar planktonic foraminifera--abrupt transitions to stadial conditions should be considered as a nonlinear response to more gradual cooling across the North Atlantic. Although the freshwater derived from melting icebergs may provide a positive feedback for enhancing and or prolonging stadial conditions, it does not trigger northern stadial events.

Spice allergy.

OBJECTIVES: To provide a review on spice allergy and its implementation in clinical practice. DATA SOURCES: PubMed searches were performed using spice allergy as the keyword for original and review articles. Selected references were also procured from the reviewed articles' references list. STUDY SELECTION: Articles were selected based on their relevance to the topic. RESULTS: Spices are available in a large variety and are widely used, often as blends. Spice allergy seems to be rare, reportedly affecting between 4 and 13 of 10,000 adults and occurring more often in women because of cosmetic use. No figures were available on children. Most spice allergens are degraded by digestion; therefore, IgE sensitization is mostly through inhalation of cross-reacting pollens, particularly mugwort and birch. The symptoms are more likely to be respiratory when exposure is by inhalation and cutaneous if by contact. Studies on skin testing and specific IgE assays are limited and showed low reliability. The diagnosis primarily depends on a good history taking and confirmation with oral challenge. The common use of spice blends makes identifying the particular offending component difficult, particularly because their components are inconsistent. CONCLUSION: Spices are widely used and contain multiple allergens, yet spice allergy is probably markedly underdiagnosed. There is a need for reliable skin testing extracts and serum specific IgE assays. Currently, the diagnosis depends on a good history taking and well-designed titrated challenge testing. Until immunotherapy becomes developed, treatment is strict avoidance, which may be difficult because of incomplete or vague labeling.

Preclinical evaluation of GS-9160, a novel inhibitor of human immunodeficiency virus type 1 integrase.

GS-9160 is a novel and potent inhibitor of human immunodeficiency virus type 1 (HIV-1) integrase (IN) that specifically targets the process of strand transfer. It is an authentic inhibitor of HIV-1 integration, since treatment of infected cells results in an elevation of two-long terminal repeat circles and a decrease of integration junctions. GS-9160 has potent and selective antiviral activity in primary human T lymphocytes producing a 50% effective concentration (EC(50)) of approximately 2 nM, with a selectivity index (50% cytotoxic concentration/EC(50)) of approximately 2,000. The antiviral potency of GS-9160 decreased by 6- to 10-fold in the presence of human serum. The antiviral activity of GS-9160 is synergistic in combination with representatives from three different classes of antiviral drugs, namely HIV-1 protease inhibitors, nonnucleoside reverse transcriptase inhibitors, and nucleotide reverse transcriptase inhibitors. Viral resistance selections performed with GS-9160 yielded a novel pattern of mutations within the catalytic core domain of IN; E92V emerged initially, followed by L74M. While E92V as a single mutant conferred 12-fold resistance against GS-9160, L74M had no effect as a single mutant. Together, these mutations conferred 67-fold resistance to GS-9160, indicating that L74M may potentiate the resistance caused by E92V. The pharmacokinetic profile of GS-9160 in healthy human volunteers revealed that once-daily dosing was not likely to achieve antiviral efficacy; hence, the clinical development of this compound was discontinued.

Using dietary exposure and physiologically based pharmacokinetic/pharmacodynamic modeling in human risk extrapolations for acrylamide toxicity.

The discovery of acrylamide (AA) in many common cooked starchy foods has presented significant challenges to toxicologists, food scientists, and national regulatory and public health organizations because of the potential for producing neurotoxicity and cancer. This paper reviews some of the underlying experimental bases for AA toxicity and earlier risk assessments. Then, dietary exposure modeling is used to estimate probable AA intake in the U.S. population, and physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) modeling is used to integrate the findings of rodent neurotoxicity and cancer into estimates of risks from human AA exposure through the diet. The goal of these modeling techniques is to reduce the uncertainty inherent in extrapolating toxicological findings across species and dose by comparing common exposure biomarkers. PBPK/PD modeling estimated population-based lifetime excess cancer risks from average AA consumption in the diet in the range of 1-4 x 10 (-4); however, modeling did not support a link between dietary AA exposure and human neurotoxicity because marginal exposure ratios were 50-300 lower than in rodents. In addition, dietary exposure modeling suggests that because AA is found in so many common foods, even big changes in concentration for single foods or groups of foods would probably have a small impact on overall population-based intake and risk. These results suggest that a more holistic analysis of dietary cancer risks may be appropriate, by which potential risks from AA should be considered in conjunction with other risks and benefits from foods.

Phosphonic acid-containing analogues of mycophenolic acid as inhibitors of IMPDH.

The design, synthesis, and IMPDH inhibitory activity of a series of phosphonic acid-containing analogues of mycophenolic acid are described.

A combination of decreased NRTI incorporation and decreased excision determines the resistance profile of HIV-1 K65R RT.

OBJECTIVE: To determine the mechanisms of resistance of K65R mutant reverse transcriptase (RT) to the currently approved nucleoside and nucleotide RT inhibitors (NRTI). METHODS: Susceptibilities of K65R mutant HIV-1 to NRTI were determined in cell culture. The Ki/Km values were measured to determine the relative binding or incorporation of the NRTI, and ATP-mediated excision of incorporated NRTI was measured to determine NRTI stability as chain terminators. RESULTS: K65R HIV-1 had decreased susceptibility to most NRTI, but increased susceptibility to zidovudine (ZDV). Ki/Km values were increased 2- to 13-fold for K65R compared to wild-type RT for all NRTI, indicating decreased binding or incorporation. However, K65R also showed decreased excision of all NRTI compared to wild-type, indicating greater stability once incorporated. At physiological nucleotide concentrations, excision of ZDV, carbovir (the active metabolite of abacavir; ABC), stavudine (d4T), and tenofovir was further decreased, while excision of didanosine (ddI), zalcitabine (ddC), lamivudine (3TC), and emtricitabine (FTC) was unchanged. The decreased binding or incorporation of ZDV by K65R appeared counteracted by decreased excision resulting in overall increased susceptibility to ZDV in cell culture. For ABC, tenofovir, and d4T, despite having decreased excision, decreased binding or incorporation resulted in reduced susceptibilities to K65R. For ddI, ddC, 3TC, and FTC, decreased binding or incorporation by K65R appeared responsible for the decreased susceptibilities in cell culture. CONCLUSIONS: NRTI resistance in cells can consist of both altered binding or incorporation and altered excision of the NRTI. For K65R, the combination of these opposing mechanisms results in decreased susceptibility to most NRTI but increased susceptibility to ZDV.

Complementary and alternative medicine education in the United States, China, and Taiwan.

As public demand for complementary and alternative medicine increases,it is important for physical medicine and rehabilitation physicians to have some basic understanding of complementary and alternative medicine or at least to appreciate some of the approved indications so that appropriate referrals can be made. Because the concept of evidence-based medicine is essential for a successful physical medicine and rehabilitation practice in either academic or private facilities, well-developed research projects, such as randomized, controlled trials of large sample size, are needed to investigate the efficacy and safety of complementary and alternative medicine therapy.

Building an organ-specific carcinogenic database for SAR analyses.

FDA reviewers need a means to rapidly predict organ-specific carcinogenicity to aid in evaluating new chemicals submitted for approval. This research addressed the building of a database to use in developing a predictive model for such an application based on structure-activity relationships (SAR). The Internet availability of the Carcinogenic Potency Database (CPDB) provided a solid foundation on which to base such a model. The addition of molecular structures to the CPDB provided the extra ingredient necessary for SAR analyses. However, the CPDB had to be compressed from a multirecord to a single record per chemical database; multiple records representing each gender, species, route of administration, and organ-specific toxicity had to be summarized into a single record for each study. Multiple studies on a single chemical had to be further reduced based on a hierarchical scheme. Structural cleanup involved removal of all chemicals that would impede the accurate generation of SAR type descriptors from commercial software programs; that is, inorganic chemicals, mixtures, and organometallics were removed. Counterions such as Na, K, sulfates, hydrates, and salts were also removed for structural consistency. Structural modification sometimes resulted in duplicate records that also had to be reduced to a single record based on the hierarchical scheme. The modified database containing 999 chemicals was evaluated for liver-specific carcinogenicity using a variety of analysis techniques. These preliminary analyses all yielded approximately the same results with an overall predictability of about 63%, which was comprised of a sensitivity of about 30% and a specificity of about 77%.

Structure-based development of a novel collagen inhibitor for MMP-1: re-designing the functions of a matrix protein.

Collagenases are a highly specific class of enzymes. In their native states, collagenases cleave only native triple helical collagen molecules at a single peptide bond between Gly775-Leu776 for Type I collagen and Gly775-Ile776 for Type II collagen. The linear sequence of collagen is about 1050 amino acids in length, where three linear peptide sequences are required to form a triple helical collagen molecule. At present, there exist no crystallographic structures of collagenase bound to native triple helical collagen; nor has it been shown that collagenase recognizes the triple helical conformation of collagen. In our study, we have used an inhibitor design structure-activity based approach to show that collagenase recognizes and cleaves triple helical collagen conformations in preference to non-triple helical collagen conformations.

Mutagenicity of food-derived carcinogens and the effect of antioxidant vitamins.

The food-derived heterocyclic amines (HCAs) 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) are mutagenic in the Ames test and produce tumors in laboratory animals, including monkeys. These HCAs have also been shown to induce gene mutations in vivo. To assess the antimutagenic effects of dietary antioxidant vitamins, beta-carotene, ascorbic acid (vitamin C), and alpha-tocopherol (vitamin E), on food-borne mutagenes/carcinogens, we evaluated the mutagenic activity of the compounds alone or combined with antioxidant vitamins. We utilized the rat lymphocyte mutation assay at the hypoxanthine guanine phosphoribosyl transferase (Hprt) locus. Female Fischer 344 rats treated with different doses (0, 2.5, 5.0, 25.0, and 50.0 mg/kg) of the carcinogens were sacrificed 5 wk after mutagen treatment. Although IQ and MeIQ slightly increased mutation frequency (MF) at some doses, a significant (P < 0.0009) increase in MF was found in animals exposed to MeIQx at 25 mg/kg. PhIP was the most mutagenic of the HCAs, with increases (P < 0.0001) in MF detected at all dose levels compared with controls. Because PhIP was the most mutagenic, it was selected for studies using the dietary antioxidant vitamins. Addition of antioxidant vitamins, singly or in a mixture, caused a significant (P < 0.0001) decrease in PhIP-induced Hprt MF. Vitamin E was the most effective at decreasing Hprt MF. In addition, we determined whether carcinogen metabolism would be affected by ingestion of vitamins. The activities of endogenous detoxification enzymes, glutathione S-transferase and glutathione peroxidase (GPx), were thus examined. Intake of beta-carotene and vitamin C without the carcinogen resulted in an increase (P < 0.05) in GPx activity. Also a modest increase in GPx activity was seen in animals that received the antioxidant mixture alone. Although the mechanisms of action of the antioxidants remain to be determined, the results indicate that dietary-derived HCA treatment induced MF in rat lymphocytes and suggest that antioxidants in food or taken as supplements could, in part, counteract such mutagenic activities.

New technology for deep light distribution in tissue for phototherapy.

Photodynamic therapy is one of several techniques developed for phototherapy for solid cancers and hematologic malignancies. Photodynamic therapy is a treatment that utilizes a molecular energy exchange between visible light and a photosensitive drug, which results in the production of 1O2, a highly reactive cytocidal oxygen species. The effect is limited to the region where light and drug are combined so that malignant tissue is destroyed and the usual side effects associated with standard cancer therapies are avoided. The light component of photodynamic therapy is customarily generated via dye-pumped or diode lasers. The cost and the complexity of lasers have seriously limited the clinical use of photodynamic therapy for malignancies. A new device technology, based on light-emitting diodes, has been developed (Light Sciences Corporation, Issaquah, WA) that allows light production inside the target tissue. This new technology will expand the current range of indications that are treatable with photodynamic therapy to include moderate- and large-volume refractorytumors. Conventional photodynamic therapy utilizes the delivery of intense light for seconds or minutes. The new approach differs from conventional photodynamic therapy in that it combines a novel interstitial light delivery system with prolonged photoactivation of photosensitive drugs. Prolonging photoactivation time in order to deliver a higher light dose results in an amplification effect, whereby the repeated activation of each photosensitive drug molecule leads to the generation of many thousands of 1O2 molecules. The production of overwhelming numbers of these powerful oxidants in individual cells and the vascular supply of tumors leads to irreversible damage and death of the targeted lesions. Results of preclinical studies have indicated a significant correlation between increased duration of photoactivation and increased volume and depth of photodynamic therapy-induced necrosis. The new developments will enable photodynamic therapy to be used effectively against refractory bulky disease as frontline therapy or in combination with chemotherapy, radiation therapy, or biologics. Perhaps most promising, many patients with advanced refractory disease may now be relieved of symptoms or may return to the treatable population.