The contributions of neonatal inhalation of copper to air pollution-induced neurodevelopmental outcomes in mice.

Exposures to ambient ultrafine particle (UFP) air pollution (AP) during the early postnatal period in mice (equivalent to human third trimester brain development) produce male-biased changes in brain structure, including ventriculomegaly, reduced brain myelination, alterations in neurotransmitters and glial activation, as well as impulsive-like behavioral characteristics, all of which are also features characteristic of male-biased neurodevelopmental disorders (NDDs). The purpose of this study was to ascertain the extent to which inhaled Cu, a common contaminant of AP that is also dysregulated across multiple NDDs, might contribute to these phenotypes. For this purpose, C57BL/6J mice were exposed from postnatal days 4-7 and 10-13 for 4 hr/day to inhaled copper oxide (CuxOy) nanoparticles at an environmentally relevant concentration averaging 171.9 ng/m3. Changes in brain metal homeostasis and neurotransmitter levels were determined following termination of exposure (postnatal day 14), while behavioral changes were assessed in adulthood. CuxOy inhalation modified cortical metal homeostasis and produced male-biased disruption of striatal neurotransmitters, with marked increases in dopaminergic function, as well as excitatory/inhibitory imbalance and reductions in serotonergic function. Impulsive-like behaviors in a fixed ratio (FR) waiting-for-reward schedule and a fixed interval (FI) schedule of food reward occurred in both sexes, but more prominently in males, effects which could not be attributed to altered locomotor activity or short-term memory. Inhaled Cu as from AP exposures, at environmentally relevant levels experienced during development, may contribute to impaired brain function, as shown by its ability to disrupt brain metal homeostasis and striatal neurotransmission. In addition, its ability to evoke impulsive-like behavior, particularly in male offspring, may be related to striatal dopaminergic dysfunction that is known to mediate such behaviors. As such, regulation of air Cu levels may be protective of public health.

Developing, characterizing and modeling CRISPR-based point-of-use pathogen diagnostics.

Recent years have seen intense interest in the development of point-of-care nucleic acid diagnostic technologies to address the scaling limitations of laboratory-based approaches. Chief among these are combinations of isothermal amplification approaches with CRISPR-based detection and readouts of target products. Here, we contribute to the growing body of rapid, programmable point-of-care pathogen tests by developing and optimizing a one-pot NASBA-Cas13a nucleic acid detection assay. This test uses the isothermal amplification technique NASBA to amplify target viral nucleic acids, followed by Cas13a-based detection of amplified sequences. We first demonstrate an in-house formulation of NASBA that enables optimization of individual NASBA components. We then present design rules for NASBA primer sets and LbuCas13a guide RNAs for fast and sensitive detection of SARS-CoV-2 viral RNA fragments, resulting in 20 - 200 aM sensitivity without any specialized equipment. Finally, we explore the combination of high-throughput assay condition screening with mechanistic ordinary differential equation modeling of the reaction scheme to gain a deeper understanding of the NASBA-Cas13a system. This work presents a framework for developing a mechanistic understanding of reaction performance and optimization that uses both experiments and modeling, which we anticipate will be useful in developing future nucleic acid detection technologies.

Methotrexate is an alternative to azathioprine in neuromyelitis optica spectrum disorders with aquaporin-4 antibodies.

BACKGROUND: Neuromyelitis optica (NMO) is a severe autoimmune inflammatory disorder associated with considerable relapse-related disability. Immunosuppression is the mainstay of treatment but many patients do not tolerate first-line immunosuppressive agents, or experience ongoing relapses. OBJECTIVE: To evaluate the effectiveness and tolerability of methotrexate in aquaporin-4 antibody seropositive NMO spectrum disorders. METHODS: Retrospective observational case series of 14 aquaporin-4 antibody positive NMO and NMO spectrum disorder patients treated with methotrexate at two specialist centres within the UK. Annualised relapse rates, Expanded Disability Status Scale scores and tolerability were evaluated. RESULTS: Median duration of treatment with methotrexate was 21.5 months (range 6-28 months) and only three patients were prescribed it first line. Median annualised relapse rate significantly decreased following treatment (0.18 during methotrexate therapy vs 1.39 premethotrexate; p<0.005). On treatment, 43% patients were relapse free, although this increased to 64% when relapses occurring within the first 3 months of treatment or on subtherapeutic doses were excluded. Disability stabilised or improved in 79%. No patients stopped methotrexate due to adverse effects. CONCLUSIONS: Methotrexate is a commonly prescribed drug in general practice and when used in NMO it reduces relapse frequency, stabilises disability and is well tolerated, even in patients who have failed one or more other treatments. We would therefore recommend methotrexate as a treatment option in NMO patients who do not tolerate first-line therapy, experience ongoing relapses or in situations where financial constraints limit the available treatment options.

Prognostic factors and disease course in aquaporin-4 antibody-positive patients with neuromyelitis optica spectrum disorder from the United Kingdom and Japan.

Neuromyelitis optica and neuromyelitis optica spectrum disorders have been recently associated with the disease-specific autoantibody aquaporin-4, thought to be pathogenic. Identifying this antibody has allowed the clinical phenotype to be broadened. It is clear that some patients with similar clinical features do not have this antibody and may have a different condition with different outcomes and prognosis. Previous clinical neuromyelitis optica and neuromyelitis optica spectrum disorder studies have included such patients. We investigated clinical outcomes and prognostic characteristics of 106 aquaporin-4 antibody-seropositive patients from the UK and Japan. We looked at predictors of disability outcomes, namely visual disability (permanent bilateral visual loss with visual acuity of <6/36 in the best eye), motor disability (permanent inability to walk further than 100 m unaided), wheelchair dependence and mortality. Data were collected largely retrospectively through review of case records. After median disease duration of 75 months, 18% had developed permanent bilateral visual disability, 34% permanent motor disability, 23% had become wheelchair dependent and 9% had died. Age at disease onset appeared to be an important predictor of disability type. Young-onset patients in the UK, but not the Japanese cohort, commonly presenting with optic neuritis, had a high risk of visual disability while older patients in both cohorts had a high risk of motor disability, regardless of their onset symptom. Genetic factors also appeared important. The UK cohort seemed to have more severe disease than the Japanese cohort, with more severe onset attacks, a higher relapse frequency and greater disability at follow-up, despite earlier immunosuppression. Moreover, within the UK cohort, there were important differences between ethnic groups, with Afro-Caribbean patients having a younger age at disease onset, more brain and multifocal attacks and higher likelihood of visual disability than Caucasian patients. Thus, age at disease onset and genetic factors are both likely to be important in determining clinical outcomes in aquaporin-4 disease. This has important implications for interpreting clinical neuromyelitis optica and neuromyelitis optica spectrum disorder studies, since clinical features and outcomes appear not to be generic across populations and may need to be tailored to individual groups. These factors need to be explored further in future prospective neuromyelitis optica and neuromyelitis optica spectrum disorder studies.

Recurrence of Cryptogenic (ESUS) Strokes in the First Year: Predictors and Outcome-A South Indian Study.

Introduction: Around 9-25% of ischemic strokes are embolic stroke of undetermined source (ESUS) with an annual recurrence risk of 4.5-5%. Regarding ESUS, studies from India are limited. Here, we studied the prevalence of cryptogenic ESUS among stroke subtypes, recurrence risk and outcome at 1 year, and their predictors. Materials and Methods: We performed a single-center study of ambispective nature. Patients above 18 years of age with a diagnosis of cryptogenic (ESUS) strokes from January 1, 2017, to December 31, 2020 (4 years), with a 1-year follow-up were recruited in our study. All the patients underwent neuroimaging computerised tomography/magnetic resonance tomography (CT/MRI) with angiography, electrocardiogram (ECG), transthoracic echo (TTE), and rhythm monitoring. Functional outcome was measured using the modified Rankin scale with scores 0-2 taken as good outcome. Results: We had 234 (11.21% of total ischemic strokes) subjects satisfying the criteria for ESUS over the study period with a mean age of 58.2 ± 12.8 years. 46 patients had a history of stroke/transient ischemic attack (TIA) at admission. 9.4% had a recurrent event at 1 year. The most important neuroimaging predictor of recurrent strokes was multiple embolic followed by superficial watershed pattern. Around 10% had more than one marker of atrial cardiopathy positive. While the risk factors, coronary artery disease (CAD), and neuroimaging pattern showed an association with recurrent events at 1 year on bivariate analysis, only the latter two remained significant on multivariate analysis. Conclusions: Our cohort of ESUS had a higher annual recurrence risk than reported before. Though vascular risk factors and ipsilateral vessel abnormalities were more in the recurrent ESUS group, it did not significantly affect the recurrence risk at 1 year. CAD and multiple embolic patterns on imaging showed an association with recurrent strokes, suggesting a possible cardiac substrate in our ESUS population as well.

Isolated Myelitis and Intramedullary Spinal Cord Abscess in Melioidosis-A Case Report.

Neuromelioidosis is a severe tropical infection with high morbidity and mortality. Isolated myelitis is an extremely rare manifestation of melioidosis which may evade diagnosis. We report a 69-year-old diabetic male patient who presented with acute flaccid paraplegia and longitudinally extensive myelitis and no systemic symptoms. MRI of spinal cord showed lower dorsal cord and conus T2 hyperintensity and microabscesses with dural enhancement. The diagnosis was clinched with blood culture growing Burkholderia pseudomallei. He rapidly developed colitis, septicemia and multiorgan dysfunction and succumbed to the illness in spite of antibiotics and aggressive supportive care. The case highlights that melioidosis should be considered as a differential diagnosis of infectious myelitis, especially in the tropics. Presence of a neutrophilic blood and cerebrospinal fluid picture and microabscesses in spinal cord are important diagnostic clues. The outcome is dismal unless the diagnosis is considered early in the disease course and managed expeditiously with sensitive antibiotics.

Attention deficit hyperactivity disorder: a rare clinical presentation of L-2-hydroxyglutaric aciduria.

L-2-hydroxyglutaric aciduria (L2HGA) is a rare autosomal recessive neurometabolic disorder caused by the deficiency of L-2-hydroxyglutarate dehydrogenase (L2HGDH) enzyme. Dystonia, ataxia, pyramidal involvement and seizures are the common clinical manifestations. Coexisting behavioural problems and intellectual disability are also seen, however attention deficit hyperactivity disorder (ADHD) as the presenting clinical feature in L2HGA is rarely described. Here, we report a 5-year-old boy with behavioural problems and mild language delay. On clinical assessment, he fulfilled the diagnostic criteria for ADHD. His MR brain sequences showed classical finding of L2HGA-bilateral symmetrical T2-weighted hyperintensity involving subcortical white matter, basal ganglia and dentate nucleus. Urine analysis showed increased levels of 2-hydroxyglutaric acid and exome sequencing (targeted leukodystrophy panel) revealed homozygous likely pathogenic mutation in L2HGDH He was started on high dose of riboflavin and levocarnitine and rehabilitative measures with which he had improvement in behavioural symptoms. This case illustrates the pivotol role of MR brain imaging in the diagnosis of inborn errors of metabolism.

Binasal congruous hemianopia secondary to functional visual loss: A case report.

INTRODUCTION: To describe an unusual case of binasal congruous hemianopia secondary to functional visual loss (FVL). PATIENT CONCERNS: A 24 year-old male was referred originally by his optician at the Emergency Eye Department of the Leicester Royal Infirmary in October 2018 with visual field changes affecting the nasal field of vision in both eyes on routine eye examination. The patient reported ongoing headaches over the last 6 weeks to 8 weeks associated with simultaneous peripheral visual field changes. He also reported rapid loss of weight over the same period of time. DIAGNOSIS: Binasal congruous hemianopia secondary to FVL. INTERVENTIONS: Full past medical and ocular history was obtained. The patient underwent full ophthalmic examination including dilated fundoscopy. Visual acuity was recorded with Snellen Chart. Color vision was assessed with Ishihara plates. Peripheral vision was assessed with both Humphrey visual fields and Goldmann visual fields. Optical coherence tomography of the macula and discs was also performed. Neuroimaging investigations included Computerized Tomography (CT) and Magnetic Resonance Imaging (MRI) of the Brain. Electrophysiology investigations included Electroretinogram and visual evoked potentials. Patient was also tested for syphilis. OUTCOMES: Humphrey visual fields and Goldmann visual fields confirmed the presence of complete binasal field defects. Optical coherence tomography, electroretinogram, visual evoked potentials, CT, MRI were all unremarkable. Ocular examination was normal. Finally, syphilis serology was negative. After 1 year of follow-up, the visual field changes have remained the same. CONCLUSION: To the best of our knowledge, this is the fourth case described in the literature with complete congruous binasal hemianopia due to FVL. We advocate thorough investigations with multimodal imaging of the fundus, neuroimaging and syphilis serology to exclude serious organic causes for binasal field defects prior to labeling such a field defect functional. Such patients may benefit from neuropsychological input to understand the psychological factors that may be contributing to the symptoms.

Pregnancy outcomes in aquaporin-4-positive neuromyelitis optica spectrum disorder.

OBJECTIVE: To investigate the association between neuromyelitis optica spectrum disorder (NMOSD) and pregnancy outcome. METHODS: An international cohort of women with aquaporin-4 antibody-positive NMOSD and ≥1 pregnancy was studied retrospectively. Multivariate logistic regression was used to investigate whether pregnancy after NMOSD onset was associated with an increased risk of miscarriage (cohort of 40 women) or preeclampsia (cohort of 57 women). RESULTS: Miscarriage rate was higher in pregnancies after NMOSD onset (42.9% [95% confidence interval 17.7%-71.1%] vs. 7.04% [2.33%-15.7%]). Pregnancies conceived after, or up to 3 years before, NMOSD onset had an increased odds ratio of miscarriage (7.28 [1.03-51.6] and 11.6 [1.05-128], respectively), independent of maternal age or history of miscarriage. Pregnancies after, or up to 1 year before, NMOSD onset ending in miscarriage were associated with increased disease activity from 9 months before conception to the end of pregnancy, compared to viable pregnancies (mean annualized relapse rate 0.707 vs. 0.100). The preeclampsia rate (11.5% [6.27%-18.9%]) was significantly higher than reported in population studies. The odds of preeclampsia were greater in women with multiple other autoimmune disorders or miscarriage in the most recent previous pregnancy, but NMOSD onset was not a risk factor. CONCLUSIONS: Pregnancy after NMOSD onset is an independent risk factor for miscarriage, and pregnancies conceived at times of high disease activity may be at increased risk of miscarriage. Women who develop NMOSD and have multiple other autoimmune disorders have greater odds of preeclampsia, independent of NMOSD onset timing.

Olfactory Pathology in Central Nervous System Demyelinating Diseases.

Olfactory dysfunction is common in multiple sclerosis (MS). Olfactory bulb and tract pathology in MS and other demyelinating diseases remain unexplored. A human autopsy cohort of pathologically confirmed cases encompassing the spectrum of demyelinating disease (MS; n = 17), neuromyelitis optica [(NMO); n = 3] and acute disseminated encephalomyelitis [(ADEM); n = 7] was compared to neuroinflammatory [herpes simplex virus encephalitis (HSE); n = 3], neurodegenerative [Alzheimer's disease (AD); n = 4] and non-neurologic (n = 8) controls. For each case, olfactory bulbs and/or tracts were stained for myelin, axons and inflammation. Inferior frontal cortex and hippocampus were stained for myelin in a subset of MS and ADEM cases. Olfactory bulb/tract demyelination was frequent in all demyelinating diseases [MS 12/17 (70.6%); ADEM 3/7 (42.9%); NMO 2/3 (66.7%)] but was absent in HSE, AD and non-neurologic controls. Inflammation was greater in the demyelinating diseases compared to non-neurologic controls. Olfactory bulb/tract axonal loss was most severe in MS where it correlated significantly with the extent of demyelination (r = 0.610, P = 0.009) and parenchymal inflammation (r = 0.681, P = 0.003). The extent of olfactory bulb/tract demyelination correlated with that found in the adjacent inferior frontal cortex but not hippocampus. We provide unequivocal evidence that olfactory bulb/tract demyelination is frequent, can occur early and is highly inflammatory, and is specific to demyelinating disease.

Neuromyelitis optica spectrum disorders with aquaporin-4 and myelin-oligodendrocyte glycoprotein antibodies: a comparative study.

IMPORTANCE: Most patients with neuromyelitis optica (NMO) and many with NMO spectrum disorder have autoantibodies against aquaporin-4 (AQP4-Abs), but recently, myelin-oligodendrocyte glycoprotein antibodies (MOG-Abs) have been found in some patients. Here, we showed that patients with NMO/NMOSD with MOG-Abs demonstrate differences when compared with patients with AQP4-Abs. OBJECTIVE: To characterize the features of patients with NMO/NMOSD with MOG-Abs and compare them with patients with AQP4-Ab-positive NMO/NMOSD. DESIGN, SETTING, AND PARTICIPANTS: This observational study was conducted at a single UK specialist center for NMO. Patients with a first demyelinating event between January 1, 2010, and April 1, 2013, seen within the Oxford NMO service and who tested positive for MOG-Abs or AQP4-Abs were included in the study. EXPOSURE: Cell-based assays using C-terminal-truncated human MOG and full-length M23-AQP4 were used to test patient serum samples for AQP4-Abs and MOG-Abs. MAIN OUTCOMES AND MEASURES: Demographic, clinical, and disability data, and magnetic resonance imaging findings. RESULTS: Twenty AQP4-Ab-positive patients and 9 MOG-Ab-positive patients were identified. Most patients in both groups were white. Ninety percent of AQP4-Ab-positive patients but only 44% MOG-Ab-positive patients were females (P = .02) with a trend toward older age at disease onset in AQP4-Ab-positive patients (44.9 vs 32.3 years; P = .05). MOG-Ab-positive patients more frequently presented with simultaneous/sequential optic neuritis and myelitis (44% vs 0%; P = .005). Onset episode severity did not differ between the 2 groups, but patients with MOG-Abs had better outcomes from the onset episode, with better recovery Expanded Disability Status Scale scores and a lower risk for visual and motor disability. Myelin-oligodendrocyte glycoprotein antibody-positive patients were more likely to have conus involvement on spinal magnetic resonance imaging (75% vs 17%; P = .02) and involvement of deep gray nuclei on brain magnetic resonance imaging (P = .03). Cerebrospinal fluid characteristics were similar in the 2 groups. A higher proportion of AQP4-Ab-positive patients relapsed (40% vs 0%; P = .03) despite similar follow-up durations. CONCLUSIONS AND RELEVANCE: Despite the fact that patients with MOG-Abs can fulfill the diagnostic criteria for NMO, there are differences when compared with those with AQP4-Abs. These include a higher proportion of males, younger age, and greater likelihood of involvement of the conus and deep gray matter structures on imaging. Additionally, patients with MOG-Abs had more favorable outcomes. Patients with AQP4-Ab-negative NMO/NMOSD should be tested for MOG-Abs.

Opportunistic infections of the retina in patients with aquaporin-4 antibody disease.

IMPORTANCE: Patients with neuromyelitis optica who have aquaporin-4 antibodies are being identified and receiving immunosuppressant treatment earlier and more aggressively as a result of increasing awareness of the importance of preventing relapses responsible for the high morbidity and mortality associated with the disease. To our knowledge, opportunistic retinal infection in patients with aquaporin-4 antibodies who are receiving immunosuppressants has not been reported to date. OBSERVATIONS: We describe 2 patients with aquaporin-4 antibodies who were receiving conventional doses of first-line immunosuppressive therapy. Both patients presented with vision loss that was initially thought to be optic neuritis attacks. The subsequent diagnoses were ocular toxoplasmosis and cytomegalovirus retinitis. CONCLUSIONS AND RELEVANCE: Retinal opportunistic infections can occur in patients with aquaporin-4 antibodies who are receiving relatively low levels of immunosuppression, may mimic optic neuritis, and are a potentially reversible cause of vision loss when treated promptly.

Longitudinally extensive transverse myelitis with and without aquaporin 4 antibodies.

IMPORTANCE: Aquaporin 4 antibody (AQP4-Ab)-negative patients with longitudinally extensive transverse myelitis (LETM) behave differently from those with AQP4-Ab. Aquaporin 4 antibody-negative neuromyelitis optica (NMO) is rare when good assays are used. OBJECTIVE: To assess if AQP4-Ab-negative patients with LETM share similar disease characteristics with AQP4-Ab-positive patients or whether they have distinct features and alternative diagnoses. DESIGN We collated clinical and paraclinical data on patients with LETM identified through the Oxford NMO clinical database. Aquaporin 4 antibodies were tested using 2 sensitive assays. We describe the features of patients with LETM, compare findings between patients with and without AQP4-Ab, and describe alternative diagnoses in AQP4-Ab-negative patients. SETTING: Single specialist UK center for NMO. PARTICIPANTS: Seventy-six adult patients with LETM. MAIN OUTCOMES AND MEASURES: Comparison of clinical and paraclinical data. RESULTS: Fifty-eight percent of patients were AQP4-Ab positive. Alternative diagnoses could usually be identified in AQP4-Ab-negative patients, including those fulfilling NMO diagnostic criteria. Only 6.5% of patients had "true" seronegative NMO and 6.5% had idiopathic LETM. There were some important differences between AQP4-Ab-positive and -negative cases, including older onset age, higher proportion of females, lower incidence of simultaneous optic neuritis, lower frequency of conus involvement, and higher prevalence of coexisting autoimmune disorders in AQP4-Ab-positive cases. Attack severity and degree of recovery were similar in the 2 groups. CONCLUSIONS AND RELEVANCE: Patients with LETM without AQP4-Ab include a number of different diagnostic categories and it is not surprising therefore that they show important differences compared with AQP4-Ab-positive patients, even when considering only those fulfilling current NMO diagnostic criteria. Thus, we suggest that diagnoses such as myelin-oligodendrocyte glycoprotein antibody disease, multiple sclerosis, acute disseminated encephalomyelitis, and postinfectious disorders should be exclusions in the NMO diagnostic criteria and AQP4-Ab-positive and antibody-negative NMO/NMO spectrum disorder cohorts should be analyzed separately.

Reduced EDSS progression in multiple sclerosis patients treated with modafinil for three years or more compared to matched untreated subjects.

BACKGROUND: Modafinil is a wakefulness-promoting drug used to treat narcolepsy, obstructive sleep apnoea, and shift-work sleep disorder. Modafinil has also been used for the treatment of fatigue and excessive sleepiness in other neurological disorders including multiple sclerosis, psychiatric disorders, and for cognitive enhancement. Recent preclinical studies suggest a potential neuroprotective effect of modafinil in neurodegenerative diseases. Therefore, we investigated its neuroprotective potential in multiple sclerosis. OBJECTIVE: To retrospectively assess disease progression in a group of MS patients that had received treatment with modafinil, and a matched group that received no treatment with modafinil. METHODS: We assessed the expanded disability status scale (EDSS) score change, over at least three years, in 30 patients with MS treated with modafinil, and in 90 patients who did not receive modafinil. The two groups were matched for initial EDSS, age, sex, type of disease, disease duration, duration of follow-up, and concomitant disease modifying therapies. Statistical analysis was performed using a general linear regression model. RESULTS: In relapsing-remitting (RR) patients treated with modafinil there was no significant EDSS change over the follow-up period. In RR patients not treated with modafinil, the mean EDSS increased significantly (0.94; p=0.0001) over the follow-up period. Independent of modafinil treatment status, our model indicated an additional mean EDSS increase of 1.1 point (p=0.0002) for progressive patients i.e. mean EDSS change was 1.1 point for modafinil treated, and 1.1+0.94=2.04 points for modafinil-untreated patients. CONCLUSION: Our results support the hypothesis that modafinil has neuroprotective potential, and may play a role in the treatment of multiple sclerosis. A prospective study will need to confirm this finding.