Objectives
Approximately 3.5 million Americans will experience a manic episode during their lifetimes. The most common causes are psychiatric illnesses such as bipolar I disorder and schizoaffective ...disorder, but mania can also occur secondary to neurological illnesses, brain injury, or neurosurgical procedures.
Methods
For this narrative review, we searched Medline for articles on the association of mania with stroke, brain tumors, traumatic brain injury, multiple sclerosis, neurodegenerative disorders, epilepsy, and neurosurgical interventions. We discuss the epidemiology, features, and treatment of these cases. We also review the anatomy of the lesions, in light of what is known about the neurobiology of bipolar disorder.
Results
The prevalence of mania in patients with brain lesions varies widely by condition, from <2% in stroke to 31% in basal ganglia calcification. Mania occurs most commonly with lesions affecting frontal, temporal, and subcortical limbic brain areas. Right‐sided lesions causing hypo‐functionality or disconnection (e.g., stroke; neoplasms) and left‐sided excitatory lesions (e.g., epileptogenic foci) are frequently observed.
Conclusions
Secondary mania should be suspected in patients with neurological deficits, histories atypical for classic bipolar disorder, and first manic episodes after the age of 40 years. Treatment with antimanic medications, along with specific treatment for the underlying neurologic condition, is typically required. Typical lesion locations fit with current models of bipolar disorder, which implicate hyperactivity of left‐hemisphere reward‐processing brain areas and hypoactivity of bilateral prefrontal emotion‐modulating regions. Lesion studies complement these models by suggesting that right‐hemisphere limbic‐brain hypoactivity, or a left/right imbalance, may be relevant to the pathophysiology of mania.
Ecologists have long sought to understand the factors controlling the structure of savanna vegetation. Using data from 2154 sites in savannas across Africa, Australia, and South America, we found ...that increasing moisture availability drives increases in fire and tree basal area, whereas fire reduces tree basal area. However, among continents, the magnitude of these effects varied substantially, so that a single model cannot adequately represent savanna woody biomass across these regions. Historical and environmental differences drive the regional variation in the functional relationships between woody vegetation, fire, and climate. These same differences will determine the regional responses of vegetation to future climates, with implications for global carbon stocks.
The human dimension of fire regimes on Earth Bowman, David M. J. S.; Balch, Jennifer; Artaxo, Paulo ...
Journal of biogeography,
December 2011, Volume:
38, Issue:
12
Journal Article
Peer reviewed
Open access
Humans and their ancestors are unique in being a fire-making species, but 'natural' (i.e. independent of humans) fires have an ancient, geological history on Earth. Natural fires have influenced ...biological evolution and global biogeochemical cycles, making fire integral to the functioning of some biomes. Globally, debate rages about the impact on ecosystems of prehistoric human-set fires, with views ranging from catastrophic to negligible. Understanding of the diversity of human fire regimes on Earth in the past, present and future remains rudimentary. It remains uncertain how humans have caused a departure from ' natural' background levels that vary with climate change. Available evidence shows that modern humans can increase or decrease background levels of natural fire activity by clearing forests, promoting grazing, dispersing plants, altering ignition patterns and actively suppressing fires, thereby causing substantial ecosystem changes and loss of biodiversity. Some of these contemporary fire regimes cause substantial economic disruptions owing to the destruction of infrastructure, degradation of ecosystem services, loss of life, and smoke-related health effects. These episodic disasters help frame negative public attitudes towards landscape fires, despite the need for burning to sustain some ecosystems. Greenhouse gas-induced warming and changes in the hydrological cycle may increase the occurrence of large, severe fires, with potentially significant feedbacks to the Earth system. Improved understanding of human fire regimes demands: (1 ) better data on past and current human influences on fire regimes to enable global comparative analyses, (2) a greater understanding of different cultural traditions of landscape burning and their positive and negative social, economic and ecological effects, and (3) more realistic representations of anthropogenic fire in global vegetation and climate change models. We provide an historical framework to promote understanding of the development and diversification of fire regimes, covering the pre-human period, human domestication of fire, and the subsequent transition from subsistence agriculture to industrial economies. All of these phases still occur on Earth, providing opportunities for comparative research.
The redox chemistry of the electron entry/exit site in Escherichia coli hydrogenase-1 is shown to play a vital role in tuning biocatalysis. Inspired by nature, we generate a HyaA-R193L variant to ...disrupt a proposed Arg–His cation−π interaction in the secondary coordination sphere of the outermost, “distal”, iron–sulfur cluster. This rewires the enzyme, enhancing the relative rate of H2 production and the thermodynamic efficiency of H2 oxidation catalysis. On the basis of Fourier transformed alternating current voltammetry measurements, we relate these changes in catalysis to a shift in the distal Fe4S42+/1+ redox potential, a previously experimentally inaccessible parameter. Thus, metalloenzyme chemistry is shown to be tuned by the second coordination sphere of an electron transfer site distant from the catalytic center.
Linked Editorials
This Editorial is part of a series. To view the other Editorials in this series, visit: http://onlinelibrary.wiley.com/doi/10.1111/bph.12956/; ...http://onlinelibrary.wiley.com/doi/10.1111/bph.12954/; http://onlinelibrary.wiley.com/doi/10.1111/bph.12955/ and http://onlinelibrary.wiley.com/doi/10.1111/bph.13112/
A new sensitive method to determine polonium-210 (210Po) and lead-210 (210Pb) in a diversity of environmental samples was developed. For fresh and marine waters, Po was pre-concentrated using a ...titanium (III) hydroxide (Ti(OH)3) co-precipitation. Solid environmental samples were digested with nitric acid (HNO3) and hydrogen peroxide (H2O2). The alpha thin layer source was prepared using CuS micro-precipitation and 210Po was measured by alpha spectrometry. Lead-210 was left to decay for up to a year and indirectly measured via its progeny, 210Po. The chemical recoveries for 210Po and 210Pb were high, 90% and 97%, respectively, for a large variety of samples and a very low minimum detectable activity (MDA) was obtained. The method was validated using standardized solutions and certified reference materials.
Fire in the Earth System Bowman, David M.J.S; Balch, Jennifer K; Artaxo, Paulo ...
Science (American Association for the Advancement of Science),
04/2009, Volume:
324, Issue:
5926
Journal Article
Peer reviewed
Fire is a worldwide phenomenon that appears in the geological record soon after the appearance of terrestrial plants. Fire influences global ecosystem patterns and processes, including vegetation ...distribution and structure, the carbon cycle, and climate. Although humans and fire have always coexisted, our capacity to manage fire remains imperfect and may become more difficult in the future as climate change alters fire regimes. This risk is difficult to assess, however, because fires are still poorly represented in global models. Here, we discuss some of the most important issues involved in developing a better understanding of the role of fire in the Earth system.
The Canadian Network for Mood and Anxiety Treatments (CANMAT) previously published treatment guidelines for bipolar disorder in 2005, along with international commentaries and subsequent updates in ...2007, 2009, and 2013. The last two updates were published in collaboration with the International Society for Bipolar Disorders (ISBD). These 2018 CANMAT and ISBD Bipolar Treatment Guidelines represent the significant advances in the field since the last full edition was published in 2005, including updates to diagnosis and management as well as new research into pharmacological and psychological treatments. These advances have been translated into clear and easy to use recommendations for first, second, and third‐ line treatments, with consideration given to levels of evidence for efficacy, clinical support based on experience, and consensus ratings of safety, tolerability, and treatment‐emergent switch risk. New to these guidelines, hierarchical rankings were created for first and second‐ line treatments recommended for acute mania, acute depression, and maintenance treatment in bipolar I disorder. Created by considering the impact of each treatment across all phases of illness, this hierarchy will further assist clinicians in making evidence‐based treatment decisions. Lithium, quetiapine, divalproex, asenapine, aripiprazole, paliperidone, risperidone, and cariprazine alone or in combination are recommended as first‐line treatments for acute mania. First‐line options for bipolar I depression include quetiapine, lurasidone plus lithium or divalproex, lithium, lamotrigine, lurasidone, or adjunctive lamotrigine. While medications that have been shown to be effective for the acute phase should generally be continued for the maintenance phase in bipolar I disorder, there are some exceptions (such as with antidepressants); and available data suggest that lithium, quetiapine, divalproex, lamotrigine, asenapine, and aripiprazole monotherapy or combination treatments should be considered first‐line for those initiating or switching treatment during the maintenance phase. In addition to addressing issues in bipolar I disorder, these guidelines also provide an overview of, and recommendations for, clinical management of bipolar II disorder, as well as advice on specific populations, such as women at various stages of the reproductive cycle, children and adolescents, and older adults. There are also discussions on the impact of specific psychiatric and medical comorbidities such as substance use, anxiety, and metabolic disorders. Finally, an overview of issues related to safety and monitoring is provided. The CANMAT and ISBD groups hope that these guidelines become a valuable tool for practitioners across the globe.
We aimed to identify unmet treatment needs for improving social and occupational functioning in early schizophrenia using a data-driven causal discovery analysis.
Demographic, clinical, and ...psychosocial measures were obtained for 276 participants from the Recovery After an Initial Schizophrenia Episode Early Treatment Program (RAISE-ETP) trial at baseline and 6-months, along with measures of social and occupational functioning from the Quality of Life Scale. The Greedy Fast Causal Inference algorithm was used to learn a partial ancestral graph modeling causal relationships across baseline variables and 6-month functioning. Effect sizes were estimated using a structural equation model. Results were validated in an independent dataset (
= 187).
In the data-generated model, greater baseline socio-affective capacity was a cause of greater baseline motivation Effect size (ES) = 0.77, and motivation was a cause of greater baseline social and occupational functioning (ES = 1.5 and 0.96, respectively), which in turn were causes of their own 6-month outcomes. Six-month motivation was also identified as a cause of occupational functioning (ES = 0.92). Cognitive impairment and duration of untreated psychosis were not direct causes of functioning at either timepoint. The graph for the validation dataset was less determinate, but otherwise supported the findings.
In our data-generated model, baseline socio-affective capacity and motivation are the most direct causes of occupational and social functioning 6 months after entering treatment in early schizophrenia. These findings indicate that socio-affective abilities and motivation are specific high-impact treatment needs that must be addressed in order to promote optimal social and occupational recovery.