High reactivity of deep biota under anthropogenic CO2 injection into basalt.

Basalts are recognized as one of the major habitats on Earth, harboring diverse and active microbial populations. Inconsistently, this living component is rarely considered in engineering operations carried out in these environments. This includes carbon capture and storage (CCS) technologies that seek to offset anthropogenic CO2 emissions into the atmosphere by burying this greenhouse gas in the subsurface. Here, we show that deep ecosystems respond quickly to field operations associated with CO2 injections based on a microbiological survey of a basaltic CCS site. Acidic CO2-charged groundwater results in a marked decrease (by ~ 2.5-4) in microbial richness despite observable blooms of lithoautotrophic iron-oxidizing Betaproteobacteria and degraders of aromatic compounds, which hence impact the aquifer redox state and the carbon fate. Host-basalt dissolution releases nutrients and energy sources, which sustain the growth of autotrophic and heterotrophic species whose activities may have consequences on mineral storage.

Changes in Neutrophil Count After Antipsychotic Prescription Among a Retrospective Cohort of Patients With Benign Neutropenia.

BACKGROUND: There is a paucity of literature regarding the effect of antipsychotics on absolute neutrophil count (ANC) of patients with benign neutropenia (BN). We evaluated the change in ANC after atypical antipsychotic prescription (excluding clozapine) in a retrospective cohort of 22 patients with BN. METHODS/PROCEDURES: Records of all patients with BN who were prescribed antipsychotics and who had ANC measured before and during antipsychotic treatment were obtained from Bronx VA Medical Center between 2005 and 2015 (inclusive). Twenty-two patients met criteria for inclusion. Individual and group mean ANC were calculated before treatment and during treatment. A paired, two-tailed t test was performed on the group ANC means. RESULTS: The group mean pretreatment ANC was 1.24 ± 0.220 K/cmm, and the mean ANC during the time of antipsychotic prescription increased to 1.40 ± 0.230 K/cmm, with a P value of 0.0045, t value of 3.18, degrees of freedom equal to 21, and 95% confidence interval of 1.30 to 1.49 K/cmm. CONCLUSIONS: There was a statistically significant increase in ANC among our cohort during the time of antipsychotic prescription. All BN patients who were prescribed antipsychotics maintained a stable neutrophil count, with none of the 22 patients with BN in this study developing agranulocytosis during treatment. Although this study is limited by a low patient count as well as other demographic factors, these findings provide initial evidence regarding the safety of prescribing atypical antipsychotics to BN patients. Further studies are needed to replicate these findings and assess for effects of individual medications.

Clinical utility of the list sign as a predictor of non-demyelinating disorders in a multiple sclerosis (MS) practice.

OBJECTIVES: Not all patients referred for evaluation of multiple sclerosis (MS) meet criteria required for MS or related entities. Identification of markers to exclude demyelinating disease may help detect patients whose presenting symptoms are inconsistent with MS. In this study, we evaluate whether patients who present a self-prepared list of symptoms during an initial visit are less likely to have demyelinating disease and whether this action, which we term the "list sign," may help exclude demyelinating disease. METHODS: Using chart review, 300 consecutive new patients who presented for evaluation to a neurologist at a tertiary MS referral center were identified retrospectively. Patients were defined as having demyelinating disease if diagnosed with MS or a related demyelinating condition. RESULTS: Of the 233 enrolled subjects, 157 were diagnosed with demyelinating disease and 74 did not meet criteria for demyelinating disease. Fifteen (8.4%) subjects had a positive list sign, of which 1 patient had demyelinating disease. The 15 subjects described a mean of 12.07 symptoms, and 8 of these patients met Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria for somatic symptom disorder. The specificity and positive predictive value of the list sign for non-demyelinating disease were 0.99 (95% confidence interval (CI) 0.96-0.99) and 0.93 (95% CI 0.66-0.99), respectively. CONCLUSION: A positive list sign may be useful to exclude demyelinating disease and to guide diagnostic evaluations for other conditions. Patients with a positive list sign also have a high incidence of somatic symptom disorder.

Reward processing abnormalities in Parkinson's disease.

The primary motor cortex is important for motor learning and response selection, functions that require information on the expected and actual outcomes of behavior. Therefore, it should receive signals related to reward. Pathways from reward centers to motor cortex exist in primates. Previously, we showed that gamma aminobutyric acid-A-mediated inhibition in the motor cortex, measured by paired transcranial magnetic stimulation, changes with expectation and uncertainty of money rewards generated by a slot machine simulation. We examined the role of dopamine in this phenomenon by testing 13 mildly affected patients with Parkinson's disease, off and on dopaminergic medications, and 13 healthy, age-matched controls. Consistent with a dopaminergic mechanism, reward expectation or predictability modulated the response to paired transcranial magnetic stimulation in controls, but not in unmedicated patients. A single dose of pramipexole restored this effect of reward, mainly by increasing the paired transcranial magnetic stimulation response amplitude during low expectation. Levodopa produced no such effect. Both pramipexole and levodopa increased risk-taking behavior on the Iowa Gambling Task. However, pramipexole increased risk-taking behavior more in patients showing lower paired transcranial magnetic stimulation response amplitude during low expectation. These results provide evidence that modulation of motor cortex inhibition by reward is mediated by dopamine signaling and that the physiological state of the motor cortex changes with risk-taking tendency in patients on pramipexole. The cortical response to reward expectation may represent an endophenotype for risk-taking behavior in patients on agonist treatment.

Drug-induced leukoencephalopathy presenting as catatonia.

We discuss the case of a 35-year-old woman who presented with thought impoverishment, disorganized behavior, and echolalia. The patient's condition progressed to treatment-refractory catatonia. She was started on oral Coenzyme Q10 after magnetic resonance imaging of the brain showed findings consistent with drug-induced leukoencephalopathy (DIL). Following improvement, she acknowledged cocaine use that suggested a diagnosis of cocaine-induced leukoencephalopathy (CIL). This case report seeks to elucidate radiological and clinical features of DIL.

Bilateral frontal transcranial direct current stimulation: Failure to replicate classic findings in healthy subjects.

OBJECTIVE: There has been no modern effort to replicate, further characterize, or quantify the dramatic effects on affect described in controlled studies from the 1960s using bilateral frontal electrodes with an extra-cephalic reference in a mixed group composed primarily of mildly depressed individuals. We performed a comprehensive, quantitative assessment of the effects of bifrontal TDCS on emotion in 21 healthy subjects. METHODS: In a double-blind crossover study, we administered tests of emotional state, affect, emotional decision-making, arousal, and psychomotor functions during sham, anodal, and cathodal TDCS. RESULTS: We found no systematic effects on any measure, despite two subjects who had pronounced mood effects in the predicted direction. There were no adverse events. CONCLUSIONS: In line with some other studies, we found no consistent effects of bifrontal TDCS on measures of emotional function of psychomotor performance. SIGNIFICANCE: These results demonstrate the safety of bilateral anterior frontal TDCS with an extra-cephalic reference, but raise questions about its effectiveness as a modulator of mood and emotional cognition, at least in healthy subjects.

Reward-related activity in the human motor cortex.

The human primary motor cortex (M1) participates in motor learning and response selection, functions that rely on feedback on the success of behavior (i.e. reward). To investigate the possibility that behavioral contingencies alter M1 activity in humans, we tested intracortical inhibition with single and paired (subthreshold/suprathreshold) transcranial magnetic stimulation during a slot machine simulation that delivered variable money rewards for three-way matches and required no movement. A two-way match before the third barrel had stopped (increased reward expectation) was associated with more paired-pulse inhibition than no match. Receiving a large reward on the preceding trial augmented this effect. A control task that manipulated attention to the same stimuli produced no changes in excitability. The origin of this reward-related activity is not clear, although dopaminergic ventral tegmental area neurons project to M1, where they are thought to inhibit output neurons and could be the source of the finding. Transcranial magnetic stimulation of M1 may be useful as a quantitative measure of reward-related activity.