2.5-Minute Fast Brain MRI with Multiple Contrasts in Acute Ischemic Stroke.

PURPOSE: To assess the performance of a 2.5-minute multi-contrast brain MRI sequence (NeuroMix) in diagnosing acute cerebral infarctions. METHODS: Adult patients with a clinical suspicion of acute ischemic stroke were retrospectively included. Brain MRI at 3 T included NeuroMix and routine clinical MRI (cMRI) sequences, with DWI/ADC, T2-FLAIR, T2-weighted, T2*, SWI-EPI, and T1-weighted contrasts. Three radiologists (R1-3) independently assessed NeuroMix and cMRI for the presence of acute infarcts (DWI ↑, ADC = or ↓) and infarct-associated abnormalities on other image contrasts. Sensitivity, specificity, and the area under the receiver operating characteristic curve (AUC) were calculated and compared using DeLong's test. Inter- and intra-rater agreements were studied with kappa statistics. Relative DWI (rDWI) and T2-FLAIR (rT2-FLAIR) signal intensity for infarctions were semi-automatically rendered, and the correlation between methods was evaluated. RESULTS: According to the reference standard, acute infarction was present in 34 out of 44 (77%) patients (63 ± 17 years, 31 men). Other infarct-associated signal abnormalities were reported in similar frequencies on NeuroMix and cMRI (p > .08). Sensitivity for infarction detection was 94%, 100%, and 94% evaluated by R1, R2, R3, for NeuroMix and 94%, 100%, and 100% for cMRI. Specificity was 100%, 90%, and 100% for NeuroMix and 100%, 100%, and 100% for cMRI. AUC for NeuroMix was .97, .95, and .97 and .97, 1, and 1 for cMRI (DeLong p = 1, .32, .15), respectively. Inter- and intra-rater agreement was κ = .88-1. The correlation between NeuroMix and cMRI was R = .73 for rDWI and R = .83 for rT2-FLAIR. CONCLUSION: Fast multi-contrast MRI NeuroMix has high diagnostic performance for detecting acute cerebral infarctions.

Market response to environmental policy via public procurement: An empirical analysis of bids and prices.

This paper studies the effect of Green Public Procurement (GPP) on competition, bids, and winning bids under two different regulation periods where the latter include more explicitly expressed GPP ambitions. Based on detailed data from Swedish internal cleaning service procurements, our results imply that environmental considerations might not influence the bids as required for GPP to be considered an effective environmental policy instrument. Over time, lower degree of competition and increased bids are found. This phenomenon can be attributed, at least in part, to regulatory influences, signifying an escalating complexity in the process of submitting bids.

Associations Between Cognition and Serotonin 1B Receptor Availability in Healthy Volunteers: A [11C]AZ10419369 Positron Emission Tomography Study.

BACKGROUND: The serotonin system has been implicated in several psychiatric disorders. All major psychiatric disorders are associated with cognitive impairment, but treatment improving cognitive deficits is lacking, partly due to limited understanding of the neurobiology of cognitive functioning. Several markers for the serotonin system have been associated with cognitive functions. Our research group previously has reported a positive correlation between serotonin (5-HT1B) receptor availability in the dorsal brainstem and visuospatial memory in a pilot study of healthy individuals. Here, we aim to replicate our previous finding in a larger group of healthy volunteers as well as to investigate putative associations between 5-HT1B receptor availability and other cognitive domains. METHODS: Forty-three healthy individuals were examined with positron emission tomography using the 5-HT1B receptor radioligand [11C]AZ10419369 and a visuospatial memory test to replicate our previous finding as well as tests of verbal fluency, cognitive flexibility, reaction time, and planning ability to explore other domains potentially associated with the serotonin system. RESULTS: Replication analysis revealed no statistically significant association between 5-HT1B receptor availability in the dorsal brainstem and visuospatial memory performance. Exploratory analyses showed age-adjusted correlations between 5-HT1B receptor availability in whole brain gray matter and specific brain regions, and number of commission errors, reaction time, and planning ability. CONCLUSIONS: Higher 5-HT1B receptor availability was associated with more false-positive responses and faster reaction time but lower performance in planning and problem-solving. These results corroborate previous research supporting an important role of the serotonin system in impulsive behavior and planning ability.

International pooled patient-level meta-analysis of ketamine infusion for depression: In search of clinical moderators.

Depression is disabling and highly prevalent. Intravenous (IV) ketamine displays rapid-onset antidepressant properties, but little is known regarding which patients are most likely to benefit, limiting personalized prescriptions. We identified randomized controlled trials of IV ketamine that recruited individuals with a relevant psychiatric diagnosis (e.g., unipolar or bipolar depression; post-traumatic stress disorder), included one or more control arms, did not provide any other study-administered treatment in conjunction with ketamine (although clinically prescribed concurrent treatments were allowable), and assessed outcome using either the Montgomery-Åsberg Depression Rating Scale or the Hamilton Rating Scale for Depression (HRSD-17). Individual patient-level data for at least one outcome was obtained from 17 of 25 eligible trials [pooled n = 809]. Rates of participant-level data availability across 33 moderators that were solicited from these 17 studies ranged from 10.8% to 100% (median = 55.6%). After data harmonization, moderators available in at least 40% of the dataset were tested sequentially, as well as with a data-driven, combined moderator approach. Robust main effects of ketamine on acute [~24-hours; ß*(95% CI) = 0.58 (0.44, 0.72); p < 0.0001] and post-acute [~7 days; ß*(95% CI) = 0.38 (0.23, 0.54); p < 0.0001] depression severity were observed. Two study-level moderators emerged as significant: ketamine effects (relative to placebo) were larger in studies that required a higher degree of previous treatment resistance to federal regulatory agency-approved antidepressant medications (≥2 failed trials) for study entry; and in studies that used a crossover design. A comprehensive data-driven search for combined moderators identified statistically significant, but modest and clinically uninformative, effects (effect size r ≤ 0.29, a small-medium effect). Ketamine robustly reduces depressive symptoms in a heterogeneous range of patients, with benefit relative to placebo even greater in patients more resistant to prior medications. In this largest effort to date to apply precision medicine approaches to ketamine treatment, no clinical or demographic patient-level features were detected that could be used to guide ketamine treatment decisions.Review Registration: PROSPERO Identifier: CRD42021235630.

Cardiopulmonary haemodynamic effects and gas exchange during apnoeic oxygenation with high-flow and low-flow nasal oxygen: A large animal study.

BACKGROUND: Apnoeic oxygenation with high-flow nasal oxygen prolongs the safe apnoeic period during induction of general anaesthesia. However, central haemodynamic effects and the characteristics of central gaseous exchange remain unexplored. OBJECTIVE: To describe mean pulmonary arterial pressure along with arterial and mixed venous blood gases and central haemodynamic parameters during apnoeic oxygenation with low-flow and high-flow nasal oxygen in pigs. DESIGN: Experimental crossover study. SETTING: Animal study of 10 healthy Swedish landrace pigs at Karolinska Institutet, Sweden, April-May 2021. INTERVENTION: The pigs were anaesthetised, their tracheas intubated and their pulmonary arteries catheterised. The animals were preoxygenated and paralysed before apnoea. Apnoeic periods between 45 and 60 min were implemented with either 70 or 10 l min -1 100% O 2 delivered via nasal catheters. In addition, seven animals underwent an apnoea without fresh gas flow. Cardiopulmonary parameters and blood gases were measured repeatedly. MAIN OUTCOME MEASURES: Mean pulmonary arterial pressure during apnoeic oxygenation with high-flow and low-flow oxygen. RESULTS: Nine pigs completed two apnoeic periods of at least 45 min with a Pa O 2 not lower than 13 kPa. The mean pulmonary arterial pressure increased during 45 min of apnoea, from 18 ±â€Š1 to 33 ±â€Š2 mmHg and 18 ±â€Š1 to 35 ±â€Š2 mmHg, at 70 and 10 l min -1 O 2 , respectively ( P  < 0.001); there was no difference between the groups ( P  = 0.87). The Pa CO 2 increased by 0.48 ±â€Š0.07 and 0.52 ±â€Š0.04 kPa min -1 , at 70 and 10 l min -1 O 2 , respectively; there was no difference between the groups ( P  = 0.22). During apnoea without fresh gas flow, the SpO 2 declined to less than 85% after 155 ±â€Š11 s. CONCLUSION: During apnoeic oxygenation in pigs, the mean pulmonary arterial pressure increased two-fold and Pa CO 2 five-fold after 45 min, while the arterial oxygen levels were maintained over 13 kPa, irrespective of high-flow or low-flow oxygen.

Electroconvulsive Therapy Versus Repetitive Transcranial Magnetic Stimulation in Patients With a Depressive Episode: A Register-Based Study.

OBJECTIVES: Electroconvulsive therapy (ECT) and repetitive transcranial magnetic stimulation (rTMS) are both effective in treating depression. Although rTMS induces fewer adverse effects, its effectiveness relative to ECT is not well established. The aim of this study was to investigate the treatment outcomes of ECT and rTMS in patients who have received both interventions. METHODS: This was a register-based observational crossover study in patients with depression who had undergone ECT and rTMS in Sweden between 2012 and 2021. Primary outcome was reduction in the Montgomery-Åsberg Depression Rating Scale-Self-report (MADRS-S) score. Secondary outcome was response defined as a 50% or greater decrease in the MADRS-S score. Subgroup analyses were performed to identify factors that predicted differential responses between rTMS and ECT. Continuous and categorical variables were analyzed using paired-samples t tests and McNemar tests, respectively. RESULTS: In total, 138 patients across 19 hospitals were included. The MADRS-S score after ECT and rTMS was reduced by 15.0 and 5.6 (P = 0.0001) points, respectively. Response rates to ECT and rTMS were 38% and 15% (P = 0.0001), respectively. Electroconvulsive therapy was superior across all subgroups classified according to age and severity of depression. CONCLUSIONS: Our results suggest that ECT is more effective than rTMS in treating depression among patients who have received both interventions. Age and baseline depression severity did not predict who would similarly benefit from rTMS and ECT.

Anorexia Nervosa With Comorbid Severe Depression: A Systematic Scoping Review of Brain Stimulation Treatments.

ABSTRACT: Major depressive disorder (MDD) is highly prevalent in individuals with anorexia nervosa (AN) and is a predictor of greater clinical severity. However, there is a limited amount of evidence supporting the use of psychotropic medications for its management. A systematic scoping review was conducted to assess the current literature on brain stimulation treatments for AN with comorbid MDD, with a specific focus on MDD treatment response and weight restoration. This review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and the PubMed, PsycInfo, and MEDLINE databases were searched until July 2022 using specific key words related to AN and brain stimulation treatments. A total of 373 citations were identified, and 49 treatment studies that met the inclusion criteria were included in the review. The initial evidence suggests that electroconvulsive therapy, repetitive transcranial magnetic stimulation, and deep-brain stimulation may be effective in managing comorbid MDD in AN. Emerging evidence suggests that transcranial direct current stimulation may have a positive effect on body mass index in individuals with severe to extreme AN. However, there is a need for the development of better measurement techniques for assessing the severity of depression in the context of AN. Controlled trials that are adequately designed to account for these limitations are highly warranted for deep-brain stimulation, electroconvulsive therapy, and repetitive transcranial magnetic stimulation and hold promise for providing clinically meaningful results.

Lung perfusion disturbances in nonhospitalized post-COVID with dyspnea-A magnetic resonance imaging feasibility study.

BACKGROUND: Dyspnea is common after COVID-19. Though the underlying mechanisms are largely unknown, lung perfusion abnormalities could contribute to lingering dyspnea. OBJECTIVES: To detect pulmonary perfusion disturbances in nonhospitalized individuals with the post-COVID condition and persistent dyspnea 4-13 months after the disease onset. METHODS: Individuals with dyspnea and matched healthy controls were recruited for dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), a 6-min walk test, and an assessment of dyspnea. The DCE-MRI was quantified using two parametric values: mean time to peak (TTP) and TTP ratio, reflecting the total lung perfusion resistance and the fraction of lung with delayed perfusion, respectively. RESULTS: Twenty-eight persons with persistent dyspnea (mean age 46.5 ± 8.0 years, 75% women) and 22 controls (mean age 44.1 ± 10.8 years, 73% women) were included. There was no systematic sex difference in dyspnea. The post-COVID group had no focal perfusion deficits but had higher mean pulmonary TTP (0.43 ± 0.04 vs. 0.41 ± 0.03, p = 0.011) and TTP ratio (0.096 ± 0.052 vs. 0.068 ± 0.027, p = 0.032). Post-COVID males had the highest mean TTP of 0.47 ± 0.02 and TTP ratio of 0.160 ± 0.039 compared to male controls and post-COVID females (p = 0.001 and p < 0.001, respectively). Correlations between dyspnea and perfusion parameters were demonstrated in males (r = 0.83, p < 0.001 for mean TTP; r = 0.76, p = 0.003 for TTP ratio), but not in females. CONCLUSIONS: DCE-MRI demonstrated late contrast bolus arrival in males with post-COVID dyspnea, suggestive of primary vascular lesions or secondary effects of hypoxic vasoconstriction. Since this effect was not regularly observed in female patients, our findings suggest sex differences in the mechanisms underlying post-COVID dyspnea, which warrants further investigation in dedicated trials.

Serotonin transporter availability in adults with autism-a positron emission tomography study.

Impairments in social interaction and communication, in combination with restricted, repetitive behaviors and interests, define the neurodevelopmental diagnosis of autism spectrum disorder (ASD). The biological underpinnings of ASD are not well known, but the hypothesis of serotonin (5-HT) involvement in the neurodevelopment of ASD is one of the longest standing. Reuptake through the 5-HT transporter (5-HTT) is the main pathway decreasing extracellular 5-HT in the brain and a marker for the 5-HT system, but in vivo investigations of the 5-HTT and the 5-HT system in ASD are scarce and so far inconclusive. To quantify possible alterations in the 5-HT system in ASD, we used positron emission tomography and the radioligand [11C]MADAM to measure 5-HTT availability in the brain of 15 adults with ASD and 15 controls. Moreover, we examined correlations between regional 5-HTT availability and behavioral phenotype assessments regarding ASD core symptoms. In the ASD group, we found significantly lower 5-HTT availability in total gray matter, brainstem, and 9 of 18 examined subregions of gray matter. In addition, several correlations between regional 5-HTT availability and social cognitive test performance were found. The results confirm the hypothesis that 5-HTT availability is lower in the brain of adult individuals with ASD, and are consistent with the theory of 5-HT involvement in ASD neurodevelopment. The findings endorse the central role of 5-HT in the physiology of ASD, and confirm the need for a continued investigation of the 5-HT system in order to disentangle the biology of ASD.

Suicidal ideation and ECT, ECT and suicidal ideation: A register study.

OBJECTIVE: Although electroconvulsive therapy (ECT) is anti-suicidal, it is not known whether the presence of suicidal ideation (SI) at baseline predicts response and remission after ECT. The aim of the study was to analyze the impact of baseline SI on response and remission following ECT treatment in a large sample of patients with depression and to assess SI before and after ECT. METHODS: This population-based register study used data from the Swedish National Quality Register for ECT and the Swedish Patient Register. Patients aged 18 years or older who had received ECT for a unipolar or bipolar depressive episode between 2011 and 2018 were included in the study. SI was defined as a score of ≥4 on the last item of the Montgomery-Åsberg Depression Rating Scale - Self Assessment (MADRS-S). Using a logistic regression model, SI at baseline was used to predict response and remission following ECT, while controlling for depression severity, psychotic symptoms, presence of a comorbid personality disorder, age, sex, electrode position, unipolar or bipolar disorder, and number of previous suicide attempts at baseline. RESULTS: In patients who exhibited SI at baseline, 53.7% (N = 632) of cases showed a response to ECT, whereas 68.4% (N = 690) of patients without SI showed a response. In addition, 27.2% (N = 320) of cases with SI achieved remission, whereas 48.5% (N = 489) of cases without SI achieved remission. The odds of achieving response and remission for patients with SI were 0.75 and 0.58 times, respectively, those for patients without SI. Of the 1178 patients with pre-treatment SI, 75.64% (N = 891) exhibited no SI at the end of treatment. Moreover, in this subgroup, the presence of a personality disorder, higher MADRS-S-score, and younger age were associated with persistent SI. CONCLUSION: The presence of SI was associated with lower ECT response and remission rates. Nevertheless, depressive symptoms and SI were reduced in a large proportion of patients across both patient groups. Clinicians should be aware of the lower likelihood of achieving a successful outcome following ECT in younger patients who present with a non-psychotic depressive episode, SI, and (suspected) personality disorders. More research is warranted regarding if these patients can achieve similar or better results with other treatments.