Relationship between defense styles and neurochemical variables of the hippocampus in patients with obsessive-compulsive disorder.

OBJECTIVES: This study aims to assess the correlation between NAA (N-acetyl-l-aspartate), CHO (choline), and CRE (creatine) levels in the hippocampus regions of individuals suffering from obsessive-compulsive disorder (OCD) and defensive styles of the ego. METHODS: The study group was composed of twenty patients with OCD and twenty healthy controls. NAA, CHO, and CRE values in the hippocampal region using proton magnetic resonance spectroscopy (1H-MRS) were measured. Participants' defense styles were ascertained by administering the Defense Style Questionnaire-40. RESULTS: The patient group's NAA levels were considerably lower than the control group's on both sides of the hippocampus. The levels of CHO and CRE did not significantly differ between the two groups. The following statistically significant correlations were discovered: in the comparison group, there were negative correlations between the scores of mature defense styles and the right and left CHO levels, as well as between the immature defense mechanism scores and the right NAA levels in both the patient and control groups. In the patient group, there were also negative correlations between the left NAA values and the scores of mature defense styles. CONCLUSION: OCD patients have lower levels of NAA in the hippocampus. To validate and extend the current findings, more research involving a greater sample size is required.

Fast 3D 31P B 1 + mapping with a weighted stack of spiral trajectory at 7 T.

PURPOSE: Phosphorus MRS (31P MRS) enables noninvasive assessment of energy metabolism, yet its application is hindered by sensitivity limitations. To overcome this, often high magnetic fields are used, leading to challenges such as spatial B 1 + $$ {\mathrm{B}}_1^{+} $$ inhomogeneity and therefore the need for accurate flip-angle determination in accelerated acquisitions with short TRs. In response to these challenges, we propose a novel short TR and look-up table-based double-angle method for fast 3D 31P B 1 + $$ {\mathrm{B}}_1^{+} $$ mapping (fDAM). METHODS: Our method incorporates 3D weighted stack-of-spiral gradient-echo acquisitions and a frequency-selective pulse to enable efficient B 1 + $$ {\mathrm{B}}_1^{+} $$ mapping based on the phosphocreatine signal at 7 T. Protocols were optimized using simulations and validated through phantom experiments. The method was validated in the human brain using a 31P 1Ch-trasmit/32Ch-receive coil and skeletal muscle using a birdcage 1H/31P volume coil. RESULTS: The results of fDAM were compared with the classical DAM. A good correlation (r = 0.95) was obtained between the two B 1 + $$ {\mathrm{B}}_1^{+} $$ maps. A 3D 31P B 1 + $$ {\mathrm{B}}_1^{+} $$ mapping in the human calf muscle was achieved in about 10:50 min using a birdcage volume coil, with a 20% extended coverage (number of voxels with SNR > 3) relative to that of the classical DAM (24 min). fDAM also enabled the first full-brain coverage 31P 3D B 1 + $$ {\mathrm{B}}_1^{+} $$ mapping in approximately 10:15 min using a 1Ch-transmit/32Ch-receive coil. CONCLUSION: fDAM is an efficient method for 31P 3D B 1 + $$ {\mathrm{B}}_1^{+} $$ mapping, showing promise for future applications in rapid 31P MRSI.

Comprehensive Analysis of Risk Factors and Prognostic Outcomes in Cases of Cerebral Venous and Sinus Thrombosis in a Tertiary Care Setting.

Background Cerebral venous and sinus thrombosis (CVT) is one of the most common causes of stroke in young people. With timely diagnosis and the right medical attention, this relatively rare neurologic condition may be curable. Finding the risk variables and outcome determinants is the aim of this study. Methodology A two-year prospective observational research was carried out in a tertiary care facility. Notable were the patient's demographics, symptomatology, and risk factor history. The Modified Rankin Scale (mRS) was employed to assess the patient's outcome and prognosis both at admission and after six weeks. The mRS scores at admission and follow-up were compared concerning outcome factors using the chi-square test. Results In all, there were 75 people with CVT. More men (42 patients, 56%) than women (33 patients, 44%), particularly in their third decade, were impacted. Polycythemia (22 patients, 29.3%) was the most prevalent risk factor, followed by the use of oral contraceptives (14 patients, 18.7%). Based on their mRS scores upon entry, 38 individuals (50.7%) were classified as functionally independent (mRS < 2), whereas 37 individuals (49.3%) were deemed functionally dependent (mRS > 2). At the six-week follow-up, 54 patients (72%) were functionally independent. Decompressive craniotomies were performed on 15 patients (20%), of which 10 (13.33%) had improvement, two (2.67%) had deterioration, and one patient passed away. The percentage of deaths was 1.33%. Two patients (2.67%) were not followed up with. Conclusion The present findings highlight that CVT predominantly affects younger individuals with a slight male predominance. The leading risk factors were polycythemia and the use of oral contraceptive pills (OCPs). Despite generally favorable prognoses with appropriate management, poorer outcomes were linked to altered consciousness, neurological deficits, and intracerebral hemorrhage (ICH) at presentation.

Repeatability of alkaline inorganic phosphate quantification in the skeletal muscle using 31P-magnetic resonance spectroscopy at 3 T.

The detection of a secondary inorganic phosphate (Pi) resonance, a possible marker of mitochondrial content in vivo, using phosphorus magnetic resonance spectroscopy (31P-MRS), poses technical challenges at 3 Tesla (T). Overcoming these challenges is imperative for the integration of this biomarker into clinical research. To evaluate the repeatability and reliability of measuring resting skeletal muscle alkaline Pi (Pialk) using with 31P-MRS at 3 T. After an initial set of experiments on five subjects to optimize the sequence, resting 31P-MRS of the quadriceps muscles were acquired on two visits (~4 days apart) using an intra-subjects design, from 13 sedentary to moderately active young male and female adults (22 ± 3 years old) within a whole-body 3 T MR system. Measurement variability attributed to changes in coil position, shimming procedure, and spectral analysis were quantified. 31P-MRS data were acquired with a 31P/-proton (1H) dual-tuned surface coil positioned on the quadriceps using a pulse-acquire sequence. Test-retest absolute and relative repeatability was analyzed using the coefficient of variation (CV) and intra-class correlation coefficients (ICC), respectively. After sequence parameter optimization, Pialk demonstrated high intra-subject repeatability (CV: 10.6 ± 5.4%, ICC: 0.80). Proximo-distal change in coil position along the length of the quadriceps introduced Pialk quantitation variability (CV: 28 ± 5%), due to magnetic field inhomogeneity with more distal coil locations. In contrast, Pialk measurement variability due to repeated shims from the same muscle volume (0.40 ± 0.09mM; CV: 6.6%), and automated spectral processing (0.37 ± 0.01mM; CV: 2.3%), was minor. The quantification of Pialk in skeletal muscle via surface coil 31P-MRS at 3 T demonstrated excellent reproducibility. However, caution is advised against placing the coil at the distal part of the quadriceps to mitigate shimming inhomogeneity.

Detection of sex-specific glutamate changes in subregions of hippocampus in an early-stage Alzheimer's disease mouse model using GluCEST MRI.

INTRODUCTION: Regional glucose hypometabolism resulting in glutamate loss has been shown as one of the characteristics of Alzheimer's disease (AD). Because the impact of AD varies between the sexes, we utilized glutamate-weighted chemical exchange saturation transfer (GluCEST) magnetic resonance imaging (MRI) for high-resolution spatial mapping of cerebral glutamate and investigated subregional changes in a sex-specific manner. METHODS: Eight-month-old male and female AD mice harboring mutant amyloid precursor protein (APPNL-F/NL-F: n = 36) and wild-type (WT: n = 39) mice underwent GluCEST MRI, followed by proton magnetic resonance spectroscopy (1H-MRS) in hippocampus and thalamus/hypothalamus using 9.4T preclinical MR scanner. RESULTS: GluCEST measurements revealed significant (p ≤ 0.02) glutamate loss in the entorhinal cortex (% change ± standard error: 8.73 ± 2.12%), hippocampus (11.29 ± 2.41%), and hippocampal fimbriae (19.15 ± 2.95%) of male AD mice. A similar loss of hippocampal glutamate in male AD mice (11.22 ± 2.33%; p = 0.01) was also observed in 1H-MRS. DISCUSSIONS: GluCEST MRI detected glutamate reductions in the fimbria and entorhinal cortex of male AD mice, which was not reported previously. Resilience in female AD mice against these changes indicates an intact status of cerebral energy metabolism. HIGHLIGHTS: Glutamate levels were monitored in different brain regions of early-stage Alzheimer's disease (AD) and wild-type male and female mice using glutamate-weighted chemical exchange saturation transfer (GluCEST) magnetic resonance imaging (MRI). Male AD mice exhibited significant glutamate loss in the hippocampus, entorhinal cortex, and the fimbriae of the hippocampus. Interestingly, female AD mice did not have any glutamate loss in any brain region and should be investigated further to find the probable cause. These findings demonstrate previously unreported sex-specific glutamate changes in hippocampal sub-regions using high-resolution GluCEST MRI.

The age-dependent development of abnormal cardiac metabolism in the peroxisome proliferator-activated receptor α-knockout mouse.

BACKGROUND AND AIMS: Peroxisome proliferator-activated receptor α (PPARα) is crucial for regulating cardiac ß-oxidation in the heart, liver, and kidney. Ageing can induce cardiac metabolic alterations, but the role of PPARα has not been extensively characterised. The aim of this research was to investigate the role of PPARα in the aged heart. METHODS: Hyperpolarized [1-13C]pyruvate was used to evaluate in vivo cardiac carbohydrate metabolism in fed and fasted young (3 months) and old (20-22 months) PPARα knockout (KO) mice versus controls. Cine MRI assessed cardiac structural and functional changes. Cardiac tissue analysis included qRT-PCR and Western blotting for Pparα, medium chain acyl-CoA dehydrenase (MCAD), uncoupling protein (UCP) 3, glucose transporter (GLUT) 4 and PDH kinase (PDK) 1,2, and 4 expression. RESULTS: PPARα-KO hearts from both young and old mice showed significantly reduced Pparα mRNA and a 58-59 % decrease in MCAD protein levels compared to controls. Cardiac PDH flux was similar in young control and PPARα-KO mice but 96 % higher in old PPARα-KO mice. Differences between genotypes were consistent in fed and fasted states, with reduced PDH flux when fasted. Increased PDH flux was accompanied by a 179 % rise in myocardial GLUT4 protein. No differences in PDK 1, 2, or 4 protein levels were observed between fed groups, indicating the increased PDH flux in aged PPARα-KO mice was not due to changes in PDH phosphorylation. CONCLUSIONS: Aged PPARα-KO mice demonstrated higher cardiac PDH flux compared to controls, facilitated by increased myocardial GLUT4 protein levels, leading to enhanced glucose uptake and glycolysis.

Association between pre-stroke frailty status and stroke risk and impact on outcomes: a systematic review and meta-analysis of 1,660,328 participants.

The prevalence of frailty is increasing, and it is associated with increased risk of diseases and adverse outcomes. Although substantial research has focused on post-stroke frailty, understanding of pre-stroke frailty remains limited. Our aim was to synthesize literature on pre-stroke frailty and stroke risk to explore their relationship and impact on prognosis. A systematic search of multiple databases was conducted to identify cohort studies published until October 28, 2023. Meta-analysis was conducted using a random effects model. Heterogeneity was assessed with the I² statistic, and publication bias was evaluated using Begg's test. Finally, we included 11 studies (n = 1,660,328 participants). The pooled hazard ratios (HRs) for stroke risk associated with pre-stroke frailty compared to non-frail individuals was 1.72 (95% confidence interval, CI: 1.46-2.02, p = 0.002, I2 = 69.2%, Begg's test: p = 0.536). The pooled HRs for mortality and the pooled relative risk (RRs) modified Rankin Scale (mRs) associated with pre-stroke frailty were 1.68 (95% CI: 1.10-2.56, p = 0.136, I2 = 49.9%, Begg's test: p = 0.296) and 3.11 (95% CI: 1.77-5.46, p = 0.192, I2 = 39.4%, Begg's test: p = 1.000), respectively. In conclusion, pre-stroke frailty is strongly associated with stroke risk and impacts its prognosis, irrespective of the measurement method. Future research should focus on prospective studies to assess the effects of early intervention for frailty. This has significant implications for primary healthcare services and frailty management.

Comparative analysis of hepatic fat quantification across 5 T, 3 T and 1.5 T: A study on consistency and feasibility.

OBJECTIVES: Magnetic resonance imaging (MRI) is a critical noninvasive technique for evaluating liver steatosis, with efficient and precise fat quantification being essential for diagnosing liver diseases. This study leverages 5 T ultra-high-field MRI to demonstrate the clinical significance of liver fat quantification, and explores the consistency and accuracy of the Proton Density Fat Fraction (PDFF) in the liver across different magnetic field strengths and measurement methodologies. METHODS: The study involved phantoms with lipid contents ranging from 0 % to 30 % and 35 participants (21 females, 14 males; average age 30.17 ± 13.98 years, body mass index 25.84 ± 4.76, waist-hip ratio 0.84 ± 0.09). PDFF measurements were conducted using chemical shift encoded (CSE) MRI at 5 T, 3 T, and 1.5 T, alongside magnetic resonance spectroscopy (MRS) at 5 T and 1.5 T for both liver and phantoms, analyzed using jMRUI software. The MRS-derived PDFF values served as the reference standard. Repeatability of 5 T MRI measurements was assessed through correlation analysis, while accuracy was evaluated using linear regression analysis against the reference standards. RESULTS: The CSE-PDFF measurements at 5 T demonstrated strong consistency with those at 3 T and 1.5 T, showing high intraclass correlation coefficients (ICC) of 0.988 and 0.980, respectively (all p < 0.001). There was also significant consistency across ROIs within liver lobes, with ICC values ranging from 0.975 to 0.986 (all p < 0.001). MRS-PDFF measurements for both phantoms and liver at 5 T and 1.5 T exhibited substantial agreement, with ICC values of 0.996 and 0.980, respectively (all p < 0.001). Particularly, ICC values for ROIs in the liver ranged from 0.963 to 0.990 (all p < 0.001). Despite overall agreement, statistically significant differences were noted in specific ROIs within the liver lobes (p = 0.004 and 0.012). The CSE and MRS PDFF measurements at 5 T displayed strong consistency, with an ICC of 0.988 (p < 0.001), and significant agreement was also found between 5 T CSE and 1.5 T MRS PDFF measurements, with an ICC of 0.978 (p < 0.001). Agreement was significant within the ROIs of the liver lobes on the same platform at 5 T, with ICC values ranging from 0.986 to 0.991 (all p < 0.001). CONCLUSION: PDFF measurements at 5 T MR imaging exhibited both accuracy and repeatability, indicating that 5 T imaging provides reliable quantification of liver fat content and shows substantial potential for clinical diagnostic applications.

Efficacy and Safety of Rituximab Treatment for Anti-N-Methyl-d-Aspartate Receptor Encephalitis Without Tumor in Children.

BACKGROUND: To evaluate the efficacy and safety of rituximab treatment for anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis without tumor in children. METHODS: Eighteen pediatric patients with NMDAR encephalitis treated with rituximab after failure of intravenous immunoglobulin (IVIG) and methylprednisolone treatment were analyzed retrospectively in terms of their medical history, clinical features, laboratory examination results, and treatments. The modified Rankin scale (mRS) score, peripheral blood CD19+ B cells, recurrence, and adverse events were used to evaluate the efficacy and safety of rituximab. RESULTS: The patients were treated with rituximab 3.2 ± 1.0 days after the end of IVIG and methylprednisolone treatment. After initial rituximab treatment for four weeks, the mRS score and number of CD19+ B cells in all patients were significantly lower than those before treatment (P < 0.05). At the last follow-up (44.1 months, 17.7 S.D.), all patients had recovered well (mRS ≤2), 14 patients (77.8%) recovered completely (mRS = 0), three patients had recurrent seizures, and one patient had mental and language impairment. Two patients had transient mild adverse events during infusion, and none of the other patients experienced severe adverse events during hospitalization or follow-up. CONCLUSIONS: Rituximab appears safe and may be effective for the treatment of anti-NMDAR encephalitis without tumor in children refractory to first-line agents.

Quantifying brain development in the HEALthy Brain and Child Development (HBCD) Study: The magnetic resonance imaging and spectroscopy protocol.

The HEALthy Brain and Child Development (HBCD) Study, a multi-site prospective longitudinal cohort study, will examine human brain, cognitive, behavioral, social, and emotional development beginning prenatally and planned through early childhood. The acquisition of multimodal magnetic resonance-based brain development data is central to the study's core protocol. However, application of Magnetic Resonance Imaging (MRI) methods in this population is complicated by technical challenges and difficulties of imaging in early life. Overcoming these challenges requires an innovative and harmonized approach, combining age-appropriate acquisition protocols together with specialized pediatric neuroimaging strategies. The HBCD MRI Working Group aimed to establish a core acquisition protocol for all 27 HBCD Study recruitment sites to measure brain structure, function, microstructure, and metabolites. Acquisition parameters of individual modalities have been matched across MRI scanner platforms for harmonized acquisitions and state-of-the-art technologies are employed to enable faster and motion-robust imaging. Here, we provide an overview of the HBCD MRI protocol, including decisions of individual modalities and preliminary data. The result will be an unparalleled resource for examining early neurodevelopment which enables the larger scientific community to assess normative trajectories from birth through childhood and to examine the genetic, biological, and environmental factors that help shape the developing brain.

In vivo biomarkers of GABAergic function in epileptic rats treated with the GAT-1 inhibitor E2730.

OBJECTIVE: E2730, an uncompetitive γ-aminobutyric acid (GABA) transporter-1 (GAT-1) inhibitor, has potent anti-seizure effects in a rodent model of chronic temporal lobe epilepsy, the kainic acid status epilepticus (KASE) rat model. In this study, we examined purported neuroimaging and physiological surrogate biomarkers of the effect of E2730 on brain GABAergic function. METHODS: We conducted a randomized cross-over study, incorporating 1-week treatments with E2730 (100 mg/kg/day subcutaneous infusion) or vehicle in epileptic post-KASE rats. KASE rats underwent serial 9.4 T magnetic resonance spectroscopy (MRS) measuring GABA and other brain metabolites, [18F]Flumazenil positron emission tomography (PET) quantifying GABAA receptor availability, quantitative electroencephalography (qEEG) and transcranial magnetic stimulation (TMS)-mediated motor activity, as well as continuous video-EEG recording to measure spontaneous seizures during each treatment. Age-matched, healthy control animals treated with E2730 or vehicle were also studied. RESULTS: E2730 treatment significantly reduced spontaneous seizures, with 8 of 11 animals becoming seizure-free. MRS revealed that E2730-treated animals had significantly reduced taurine levels. [18F]Flumazenil PET imaging revealed no changes in GABA receptor affinity or density during E2730 treatment. The power of gamma frequency oscillations in the EEG was decreased significantly in the auditory cortex and hippocampus of KASE and control rats during E2730 treatment. Auditory evoked gamma frequency power was enhanced by E2730 treatment in the auditory cortex of KASE and healthy controls, but only in the hippocampus of KASE rats. E2730 did not influence motor evoked potentials triggered by TMS. SIGNIFICANCE: This study identified clinically relevant changes in multimodality imaging and functional purported biomarkers of GABAergic activity during E2730 treatment in epileptic and healthy control animals. These biomarkers could be utilized in clinical trials of E2730 and potentially other GABAergic drugs to provide surrogate endpoints, thereby reducing the cost of such trials.

Prefrontal Metabolite Alterations in Individuals with Posttraumatic Stress Disorder: A 7T Magnetic Resonance Spectroscopy Study.

Background: Evidence from animal and human studies suggests glutamatergic dysfunction in posttraumatic stress disorder (PTSD). The purpose of this study was to investigate glutamate abnormalities in the dorsolateral prefrontal cortex (DLFPC) of individuals with PTSD using 7T MRS, which has better spectral resolution and signal-to-noise ratio than lower field strengths, thus allowing for better spectral quality and higher sensitivity. We hypothesized that individuals with PTSD would have lower glutamate levels compared to trauma-exposed individuals without PTSD and individuals without trauma exposure. Additionally, we explored potential alterations in other neurometabolites and the relationship between glutamate and psychiatric symptoms. Methods: Individuals with PTSD (n = 27), trauma-exposed individuals without PTSD (n = 27), and individuals without trauma exposure (n = 26) underwent 7T MRS to measure glutamate and other neurometabolites in the left DLPFC. The severities of PTSD, depression, anxiety, and dissociation symptoms were assessed. Results: We found that glutamate was lower in the PTSD and trauma-exposed groups compared to the group without trauma exposure. Furthermore, N-acetylaspartate (NAA) was lower and lactate was higher in the PTSD group compared to the group without trauma exposure. Glutamate was negatively correlated with depression symptom severity in the PTSD group. Glutamate was not correlated with PTSD symptom severity. Conclusion: In this first 7T MRS study of PTSD, we observed altered concentrations of glutamate, NAA, and lactate. Our findings provide evidence for multiple possible pathological processes in individuals with PTSD. High-field MRS offers insight into the neurometabolic alterations associated with PTSD and is a powerful tool to probe trauma- and stress-related neurotransmission and metabolism in vivo.

Whether Present Era Demand Change in Pharmaceutical Promotional Ways to be More Eco- and Doctor-Friendly? An Observational Study.

Aim: Pharmaceutical promotion is the principal aspect of the healthcare system. In this study, we aimed to portray the opinion of doctors and medical representatives (MRs) on conventional pharmaceutical ways (usage of promotional or educational paper materials and physician drug samples) for pharmaceutical promotion. Materials and Methods: In this cross-sectional observational study, data were collected from doctors and MRs across India using self-administered Google forms. Data were analyzed, and results were drawn. Results: A total of 314 doctors and 272 MRs participated in the study. As per 95.5% of doctors, continuing medical education (CME)/books/online information is the most common and convenient method to update medical knowledge, whereas 67.9% of MRs also think the same. Only 5.5% of doctors prefer paper material provided by pharmaceutical companies to update their knowledge. Most doctors say paper materials provided by pharmaceutical companies contribute less than 25% to product information, rather CME, books, and online information contribute significantly. MRs also think similarly. 66.2% of MRs agree that more than 25% of paper material gets wasted due to non-distribution. 73.2% of doctors and 75.4% of MRs agree that the use of paper materials for product promotion is not cost-effective, even if it contributes to deforestation. Only 51% of doctors use more than 50% of medical samples in patient care and only half of doctors and MRs think expired medical samples are disposed of correctly. 56.1% of doctors and 71.4% of MRs think a significant amount of medical samples are wasted and are hazardous to the environment. Conclusions: Both doctors and MRs are of the opinion that the conventional method of paper promotion, that is, paper material and drug samples, is not cost-effective and also not eco-friendly. Hence, need to rethink - is there a need to change with time?

Role of Magnetic Resonance Spectroscopy in Evaluating Choline Levels in Gallbladder Carcinoma: A Comprehensive Review.

Gallbladder carcinoma (GBC) presents a significant clinical challenge due to its aggressive nature and often asymptomatic progression, resulting in late-stage diagnoses and a poor prognosis. Early detection and accurate staging are pivotal for improving patient outcomes, highlighting the critical role of advanced imaging techniques in oncological practice. Magnetic resonance spectroscopy (MRS) has emerged as a valuable non-invasive tool capable of assessing biochemical changes within tissues, including alterations in choline metabolism-a biomarker indicative of cell membrane turnover and proliferation. This review explores the application of MRS in evaluating choline levels in gallbladder carcinoma, synthesizing current literature to elucidate its potential in clinical settings. By analyzing studies investigating the correlation between choline levels detected via MRS and tumor characteristics, this review underscores MRS's role in enhancing diagnostic precision and guiding therapeutic decision-making. Moreover, it discusses the challenges and limitations associated with MRS in clinical practice alongside future research and technological advancement directions. Ultimately, integrating MRS into the diagnostic armamentarium for gallbladder carcinoma promises to improve early detection and treatment outcomes. This review provides insights into the evolving landscape of MRS in oncology, emphasizing its contribution to personalized medicine approaches aimed at optimizing patient care and management strategies for GBC.

Glutamate dynamics and BOLD response during OCD symptom provocation in the lateral occipital cortex: A 7 Tesla fMRI-fMRS study.

Obsessive-compulsive disorder (OCD) is linked with dysfunction in frontal-striatal, fronto-limbic, and visual brain regions. Research using proton magnetic resonance spectroscopy (1H-MRS) suggests that altered neurometabolite levels, like glutamate, may contribute to this dysfunction. However, static neurometabolite levels in OCD patients have shown inconsistent results, likely due to previous studies' limited focus on neurometabolite dynamics. We employ functional MRS (fMRS) and functional magnetic resonance imaging (fMRI) to explore these dynamics and brain activation during OCD symptom provocation. We utilized a combined 7-tesla fMRI-fMRS setup to examine task-related BOLD response and glutamate changes in the lateral occipital cortex (LOC) of 30 OCD participants and 34 matched controls during an OCD-specific symptom provocation task. The study examined main effects and between-group differences in brain activation and glutamate levels during the task. A whole sample task-effects analysis on data meeting predefined quality criteria showed significant glutamate increases (n = 41 (22 OCD, 19 controls), mean change: 3.2 %, z = 3.75, p < .001) and task activation (n = 54 (26 OCD, 28 controls), p < .001) in the LOC during OCD blocks compared to neutral blocks. However, no differences in task-induced glutamate dynamics or activation between groups were found, nor a correlation between glutamate levels and task activation. We were able to measure task-induced increases in glutamate and BOLD levels, emphasizing its feasibility for OCD research. The absence of group differences highlights the need for further exploration to discern to what extent neurometabolite dynamics differ between OCD patients and controls. Once established, future studies can use pre-post intervention fMRS-fMRI to probe the effects of therapies modulating glutamate pathways in OCD.

Brain morphometry and short-term stroke outcome.

OBJECTIVE: Aim: The aim of the research was to investigate associations between brain morphometric changes and short-term stroke outcome. PATIENTS AND METHODS: Materials and Methods: In this study, 294 patients with acute stroke were enrolled. All participants underwent magnetic resonance imaging (MRI) and computed tomography (CT) assessment as well as clinical-neurological and cognitive testing. RESULTS: Results: In the multivariable regression analysis, bicaudate index (OR = 1.3; 95 % CI 1.1 - 1.7, p=0.018) and ventricular index (OR = 0.7; CI 0.5 - 0.9, p=0.005) were associated with an unfavourable short-term stroke outcome. The univariable regression analysis revealed significant associations between mini-mental state examination scale score (MMSE) and width of the longitudinal cerebral fissure in the anterior part of the frontal lobes (FI) (b -0.8, 95% CI -1.6 - -0.1, p=0.037) as well as width of the cerebral fissure in the area of the skull vault (SW) (b -0.9, 95% CI -1.8 - -0.1, p=0.023). In the multivariable regression model bicaudate index was associated with MMSE score (b coefficient (b) = -1.2; 95 % CI -2.1 - -0.3, p = 0.011). CONCLUSION: Conclusions: our results show that altered brain morphometric indices are associated with unfavourable short-term stroke outcome and cognitive decline.

1H-MRS reveals abnormal energy metabolism and excitatory-inhibitory imbalance in a chronic migraine-like state induced by nitroglycerin in mice.

BACKGROUND: Chronic migraine is closely related to the dysregulation of neurochemical substances in the brain, with metabolic imbalance being one of the proposed causes of chronic migraine. This study aims to evaluate the metabolic changes between energy metabolism and excitatory and inhibitory neurotransmitters in key brain regions of mice with chronic migraine-like state and to uncover the dysfunctional pathways of migraine. METHODS: A chronic migraine-like state mouse model was established by repeated administration of nitroglycerin (NTG). We used von Frey filaments to assess the mechanical thresholds of the hind paw and periorbital in wild-type and familial hemiplegic migraine type 2 mice. After the experiments, tissue was collected from five brain regions: the somatosensory cortex (SSP), hippocampus, thalamus (TH), hypothalamus, and the spinal trigeminal nucleus caudalis (TNC). Proton magnetic resonance spectroscopy (1H-MRS) was employed to study the changes in brain metabolites associated with migraine, aiming to explore the mechanisms underlying metabolic imbalance in chronic migraine-like state. RESULTS: In NTG-induced chronic migraine-like state model, we observed a significant reduction in energy metabolism during central sensitization, an increase in excitatory neurotransmitters such as glutamate, and a tendency for inhibitory neurotransmitters like GABA to decrease. The TNC and thalamus were the most affected regions. Furthermore, the consistency of N-acetylaspartate levels highlighted the importance of the TNC-TH-SSP pathway in the ascending nociceptive transmission of migraine. CONCLUSION: Abnormal energy metabolism and neurotransmitter imbalance in the brain region of NTG-induced chronic migraine-like state model are crucial mechanisms contributing to the chronicity of migraine.

Prevalence and risk factors associated with nasal carriage of methicillin-resistant staphylococci in horses and their caregivers.

Antimicrobial resistance is a global threat, and pet-associated strains may pose a risk to human health. Equine veterinarians are at high risk of carrying methicillin-resistant staphylococci (MRS), but specific risk factors remain elusive, and few data are available for other personnel involved in the horse industry. The prevalence, characteristics, and risk factors for nasal carriage of MRS in horses and their caregivers were studied in northwestern Italy. Nasal swabs from 110 asymptomatic horses housed at 21 barns and 34 human caregivers were collected. Data on barns, horses, and personnel were acquired through questionnaires. The samples were incubated in selective media, and the bacterial isolates were identified by mass spectrometry. Risk factors were investigated by Poisson regression. MRS were isolated from 33 horses (30%), 11 humans (32.4%) and 3 environmental samples (14.2%). Most isolates were multidrug resistant (MDRS). The prevalence of MRS and MDRS was greater in racehorses and their personnel than in pleasurable and jumping/dressing horses. MRS carriage in caregivers was associated with an increased prevalence of MRS carriage in horses. The frequency of antimicrobial treatments administered in the barn during the last 12 months was a risk factor for MRS carriage in horses [prevalence ratio (PR) 3.97, 95% CI 1.11, 14.13] and caregivers (PR 2.00, 95% CI 1.05, 3.82), whereas a good ventilation index of the horse tabling environment was a protective factor (PR 0.43, 95% CI 0.20, 0.92). Our data reveal relevant interactions occurring between bacterial communities of horses and humans that share the same environment, suggesting that One Health surveillance programs should be implemented.

18F-DPA714 PET/MRI as a potential imaging tool for detecting possible antibody-negative autoimmune encephalitis: a prospective study.

BACKGROUND AND OBJECTIVES: Conventional magnetic resonance imaging (MRI) used for detecting possible antibody-negative autoimmune encephalitis (AIE) often fails to meet the diagnostic requirements of this disease. Positron emission tomography (PET) with a translocator protein radioligand can help visualize microglia distribution density in inflammation-related diseases, thereby offering potentially incremental value to conventional MRI for the in vivo assessment of possible antibody-negative AIE. METHODS: In this prospective study, 15 participants diagnosed with possible antibody-negative AIE and 10 healthy controls were enrolled (ClinicalTrials.gov: NCT05293405, dated March 15, 2022). All participants underwent hybrid 18F-DPA714 PET/MRI and evaluation for modified Rankin scale (mRS) score, clinical assessment scale for AIE (CASE), and appropriate antibodies. A positive finding was defined as the intensity of 18F-DPA714 uptake that was above a threshold of mean standardized uptake value ratio (SUVR) + two standard deviations of SUVR within the corresponding brain regions of healthy controls. RESULTS: The positive detection rate of 18F-DPA714 PET for possible antibody-negative AIE was significantly higher than that of brain MRI (10/15 [67%] vs. 3/15 [20%]; P = 0.039). In addition, both the intensity and extent of 18F-DPA714 uptake were significantly associated with the CASE score (P = 0.002 and 0.001). Meanwhile, SUVR levels in the cerebellar region were significantly higher in patients with ataxia than in those without ataxia (P = 0.006). Furthermore, 18F-DPA714 uptake decreased in 5/10 [50%] patients who underwent follow-up PET/MRI, which mirrored their symptom relief. CONCLUSION: 18F-DPA714 PET demonstrated its potentially incremental value to conventional MRI for detecting possible antibody-negative AIE.

AB006. The use of magnetic resonance spectroscopy in the differential diagnosis of paediatric intracranial tumours.

BACKGROUND: Despite different intracranial tumour subtypes varying largely in their prognoses and recommended treatment regimens, they can have markedly similar appearances on standard radiology, especially in paediatric patients where they tend to occur in the midline. There is a need for a non-invasive, accurate method of determining tumour diagnosis to help expedite treatment planning. Existing studies have found magnetic resonance spectroscopy (MRS) to have value in diagnosing intracranial tumours in adults. The aim of this study was to investigate whether MRS could be accurate in diagnosing and grading paediatric intracranial tumours. METHODS: The hospital database was retrospectively searched for paediatric intracranial tumour patients ≤18 years that had 1.5 T MRS data available. Medical and demographic data were collected from existing records including MRS metabolites N-acetylaspartate (NAA), creatine (Cr), and choline (Cho), and final histopathologic diagnosis. MRS metabolites were then statistically compared against final histopathologic diagnosis. RESULTS: In total, 166 patients were included. In the overall cohort, the tumour to control tissue Cr ratio was significantly higher in grade 1 than grade 4 tumours (P=0.03), and tumour Cho/Cr was significantly higher in grade 4 than grade 1 tumours (P=0.004). When analyzing tumour subtypes, control tissue Cr was significantly higher in embryonal/germ cell tumours than glial tumours (P=0.044). Binary logistic regression models including MRS metabolite ratios and age, sex, and tumour location covariates could diagnose grade 4 tumours [area under the curve (AUC) =0.857], and grade 1 tumours (AUC =0.766) with reasonable accuracy. CONCLUSIONS: This study suggests that MRS has benefits in the non-invasive diagnosis of paediatric intracranial tumours, in particular, identifying low- and high-grade tumours. Future advances in MRS technology, and larger cross-sectional studies will be necessary to improve the clinical integration of MRS for accurate non-invasive paediatric intracranial tumour diagnosis.