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Diffusion tensor imaging (DTI) findings from emerging studies of cortical white-matter integrity in Parkinson’s disease (PD) without dementia are inconclusive. When white-matter changes have been found, their relationship to cognitive functioning in PD has not been carefully investigated. To better characterize changes in tissue diffusivity and to understand their functional significance, the present study conducted DTI in 25 PD patients without dementia and 26 controls of similar ages. An automated tract-based DTI method was used. Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were analyzed. Neuropsychological measures of executive functioning (working memory, verbal fluency, cognitive flexibility, inhibitory control) and visuospatial ability were then correlated with regions of interest that showed abnormal diffusivity in the PD group. We found widespread reductions in FA and increases in MD in the PD group relative to controls. These changes were predominantly related to an increase in RD. Increased AD in the PD group was limited to specific frontal tracks of the right hemisphere, possibly signifying more significant tissue changes. Motor-symptom severity did not correlate with FA. However, different measures of executive functioning and visuospatial ability correlated with FA in different segments of tracts, which contain fiber pathways to cortical regions that are thought to support specific cognitive processes. The findings suggest that abnormal tissue diffusivity may be sensitive to subtle cognitive changes in PD, some of which may be prognostic of future cognitive decline.

Working memory (WM) represents the brain's ability to maintain information in a readily available state for short periods of time. This study examines the resting-state cortical activity patterns that are most associated with performance on a difficult working-memory task.Magnetoencephalographic (MEG) band-passed (delta/theta (1-7 Hz), alpha (8-13 Hz), beta (14-30 Hz)) and sensor based regional power was collected in a population of adult men (18-28 yrs, n = 24) in both an eyes-closed and eyes-open resting state. The normalized power within each resting state condition as well as the normalized change in power between eyes closed and open (zECO) were correlated with performance on a WM task. The regional and band-limited measures that were most associated with performance were then combined using singular value decomposition (SVD) to determine the degree to which zECO power was associated with performance on the three-back verbal WM task.Changes in power from eyes closed to open revealed a significant decrease in power in all band-widths that was most pronounced in the posterior brain regions (delta/theta band). zECO right posterior frontal and parietal cortex delta/theta power were found to be inversely correlated with three-back working memory performance. The SVD evaluation of the most correlated zECO metrics then provided a singular measure that was highly correlated with three-back performance (r = -0.73, p

Parkinson's disease (PD) disrupts temporal processing, but the neuronal sources of deficits and their response to dopamine (DA) therapy are not understood. Though the striatum and DA transmission are thought to be essential for timekeeping, potential working memory (WM) and executive problems could also disrupt timing.The present study addressed these issues by testing controls and PD volunteers 'on' and 'off' DA therapy as they underwent fMRI while performing a time-perception task. To distinguish systems associated with abnormalities in temporal and non-temporal processes, we separated brain activity during encoding and decision-making phases of a trial. Whereas both phases involved timekeeping, the encoding and decision phases emphasized WM and executive processes, respectively. The methods enabled exploration of both the amplitude and temporal dynamics of neural activity. First, we found that time-perception deficits were associated with striatal, cortical, and cerebellar dysfunction. Unlike studies of timed movement, our results could not be attributed to traditional roles of the striatum and cerebellum in movement. Second, for the first time we identified temporal and non-temporal sources of impaired time perception. Striatal dysfunction was found during both phases consistent with its role in timekeeping. Activation was also abnormal in a WM network (middle-frontal and parietal cortex, lateral cerebellum) during encoding and a network that modulates executive and memory functions (parahippocampus, posterior cingulate) during decision making. Third, hypoactivation typified neuronal dysfunction in PD, but was sometimes characterized by abnormal temporal dynamics (e.g., lagged, prolonged) that were not due to longer response times. Finally, DA therapy did not alleviate timing deficits.Our findings indicate that impaired timing in PD arises from nigrostriatal and mesocortical dysfunction in systems that mediate temporal and non-temporal control-processes. However, time perception impairments were not improved by DA treatment, likely due to inadequate restoration of neuronal activity and perhaps corticostriatal effective-connectivity.

In this review article we have consolidated the imaging literature of patients with schizophrenia across the full spectrum of modalities in radiology including computed tomography (CT), morphologic magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), magnetic resonance spectroscopy (MRS), positron emission tomography (PET), and magnetoencephalography (MEG). We look at the impact of various subtypes of schizophrenia on imaging findings and the changes that occur with medical and transcranial magnetic stimulation (TMS) therapy. Our goal was a comprehensive multimodality summary of the findings of state-of-the-art imaging in untreated and treated patients with schizophrenia. Clinical imaging in schizophrenia is used to exclude structural lesions which may produce symptoms that may mimic those of patients with schizophrenia. Nonetheless one finds global volume loss in the brains of patients with schizophrenia with associated increased cerebrospinal fluid (CSF) volume and decreased gray matter volume. These features may be influenced by the duration of disease and or medication use. For functional studies, be they fluorodeoxyglucose positron emission tomography (FDG PET), rs-fMRI, task-based fMRI, diffusion tensor imaging (DTI) or MEG there generally is hypoactivation and disconnection between brain regions. However, these findings may vary depending upon the negative or positive symptomatology manifested in the patients. MR spectroscopy generally shows low N-acetylaspartate from neuronal loss and low glutamine (a neuroexcitatory marker) but glutathione may be elevated, particularly in non-treatment responders. The literature in schizophrenia is difficult to evaluate because age, gender, symptomatology, comorbidities, therapy use, disease duration, substance abuse, and coexisting other psychiatric disorders have not been adequately controlled for, even in large studies and meta-analyses.

BackgroundSpatial cognition deteriorates in Parkinson’s disease (PD), but the neural substrates are not understood, despite the risk for future dementia. It is also unclear whether deteriorating spatial cognition relates to changes in other cognitive domains or contributes to motor dysfunction.ObjectiveThis study aimed to identify functional connectivity abnormalities in cognitively normal PD (PDCN) in regions that support spatial cognition to determine their relationship to interfacing cognitive functions and motor disability, and to determine if they predict cognitive and motor progression 2 years later in a PDCN subsample.MethodsSixty-three PDCN and 43 controls underwent functional MRI while judging whether pictures, rotated at various angles, depicted the left or right hand. The task activates systems that respond to increases in rotation angle, a proxy for visuospatial difficulty. Angle-modulated functional connectivity was analyzed for frontal cortex, posterior cortex, and basal ganglia regions.ResultsTwo aberrant connectivity patterns were found in PDCN, which were condensed into principal components that characterized the strength and topology of angle-modulated connectivity. One topology related to a marked failure to amplify frontal, posterior, and basal ganglia connectivity with other brain areas as visuospatial demands increased, unlike the control group (control features). Another topology related to functional reorganization whereby regional connectivity was strengthened with brain areas not recruited by the control group (PDCN features). Functional topologies correlated with diverse cognitive domains at baseline, underscoring their influences on spatial cognition. In PDCN, expression of topologies that were control features predicted greater cognitive progression longitudinally, suggesting inefficient communications within circuitry normally recruited to handle spatial demands. Conversely, stronger expression of topologies that were PDCN features predicted less longitudinal cognitive decline, suggesting functional reorganization was compensatory. Parieto-occipital topologies (control features) had different prognostic implications for longitudinal changes in motor disability. Expression of one topology predicted less motor decline, whereas expression of another predicted increased postural instability and gait disturbance (PIGD) feature severity. Concurrently, greater longitudinal decline in spatial cognition predicted greater motor and PIGD feature progression, suggesting deterioration in shared substrates.ConclusionThese novel discoveries elucidate functional mechanisms of visuospatial cognition in PDCN, which foreshadow future cognitive and motor disability.

Decline in semantic cognition in early stages of Parkinson’s disease (PD) is a leading risk factor for future dementia, yet the underlying neural mechanisms are not understood. The present study addressed this gap by investigating the functional connectivity of regions involved in semantic recollection. We further examined whether microtubule-associated protein tau (MAPT) risk variants, which may accelerate cognitive decline, altered the strength of regional functional connections. Cognitively normal PD and healthy elder controls underwent fMRI while performing a fame-discrimination task, which activates the semantic network. Analyses focused on disturbances in fame-modulated functional connectivity in PD for regions that govern semantic recollection and interrelated processes. Group differences were found in multiple connectivity features, which were reduced into principal components that reflected the strength of fame-modulated regional couplings with other brain areas. Despite the absence of group differences in semantic cognition, two aberrant connectivity patterns were uncovered in PD. One pattern was related to a loss in frontal, parietal, and temporal connection topologies that governed semantic recollection in older controls. Another pattern was characterized by functional reconfiguration, wherein frontal, parietal, temporal and caudate couplings were strengthened with areas that were not recruited by controls. Correlations between principal component scores and cognitive measures suggested that reconfigured frontal coupling topologies in PD supported compensatory routes for accessing semantic content, whereas reconfigured parietal, temporal, and caudate connection topologies were detrimental or unrelated to cognition. Increased tau transcription diminished recruitment of compensatory frontal topologies but amplified recruitment of parietal topologies that were unfavorable for cognition. Collectively, the findings provide a new understanding of early vulnerabilities in the functional architecture of regional connectivity during semantic recollection in cognitively normal PD. The findings also have implications for tracking cognitive progression and selecting patients who stand to benefit from therapeutic interventions.

We report a patient with an optic nerve sheath meningioma whose diagnosis and management were guided by using Gallium-68 DOTA-Tyr3-octreotatate (68Ga-DOTATATE).Positron Emission Tomography-Computed Tomography (PET-CT).

Superparamagnetic relaxometry (SPMR) is a highly sensitive technique for the in vivo detection of tumor cells and may improve early stage detection of cancers. SPMR employs superparamagnetic iron oxide nanoparticles (SPION). After a brief magnetizing pulse is used to align the SPION, SPMR measures the time decay of SPION using super-conducting quantum interference device (SQUID) sensors. Substantial research has been carried out in developing the SQUID hardware and in improving the properties of the SPION. However, little research has been done in the pre-processing of sensor signals and post-processing source modeling in SPMR. In the present study, we illustrate new pre-processing tools that were developed to: (1) remove trials contaminated with artifacts, (2) evaluate and ensure that a single decay process associated with bounded SPION exists in the data, (3) automatically detect and correct flux jumps, and (4) accurately fit the sensor signals with different decay models. Furthermore, we developed an automated approach based on multi-start dipole imaging technique to obtain the locations and magnitudes of multiple magnetic sources, without initial guesses from the users. A regularization process was implemented to solve the ambiguity issue related to the SPMR source variables. A procedure based on reduced chi-square cost-function was introduced to objectively obtain the adequate number of dipoles that describe the data. The new pre-processing tools and multi-start source imaging approach have been successfully evaluated using phantom data. In conclusion, these tools and multi-start source modeling approach substantially enhance the accuracy and sensitivity in detecting and localizing sources from the SPMR signals. Furthermore, multi-start approach with regularization provided robust and accurate solutions for a poor SNR condition similar to the SPMR detection sensitivity in the order of 1000 cells. We believe such algorithms will help establishing the industrial standards for SPMR when applying the technique in pre-clinical and clinical settings. [ABSTRACT FROM AUTHOR]

In Parkinson’s disease (PD) functional changes in the brain occur years before significant cognitive symptoms manifest yet core large-scale networks that maintain cognition and predict future cognitive decline are poorly understood. The present study investigated internetwork functional connectivity of visual (VN), anterior and posterior default mode (aDMN, pDMN), left/right frontoparietal (LFPN, RFPN), and salience (SN) networks in 63 cognitively normal PD (PDCN) and 43 healthy controls who underwent resting-state functional MRI. The functional relevance of internetwork coupling topologies was tested by their correlations with baseline cognitive performance in each group and with 2-year cognitive changes in a PDCN subsample. To disentangle heterogeneity in neurocognitive functioning, we also studied whether α-synuclein (SNCA) and microtubule-associated protein tau (MAPT) variants alter internetwork connectivity and/or accelerate cognitive decline. We found that internetwork connectivity was largely preserved in PDCN, except for reduced pDMN-RFPN/LFPN couplings, which correlated with poorer baseline global cognition. Preserved internetwork couplings also correlated with domain-specific cognition but differently for the two groups. In PDCN, stronger positive internetwork coupling topologies correlated with better cognition at baseline, suggesting a compensatory mechanism arising from less effective deployment of networks that supported cognition in healthy controls. However, stronger positive internetwork coupling topologies typically predicted greater longitudinal decline in most cognitive domains, suggesting that they were surrogate markers of neuronal vulnerability. In this regard, stronger aDMN-SN, LFPN-SN, and/or LFPN-VN connectivity predicted longitudinal decline in attention, working memory, executive functioning, and visual cognition, which is a risk factor for dementia. Coupling strengths of some internetwork topologies were altered by genetic variants. PDCN carriers of the SNCA risk allele showed amplified anticorrelations between the SN and the VN/pDMN, which supported cognition in healthy controls, but strengthened pDMN-RFPN connectivity, which maintained visual memory longitudinally. PDCN carriers of the MAPT risk allele showed greater longitudinal decline in working memory and increased VN-LFPN connectivity, which in turn predicted greater decline in visuospatial processing. Collectively, the results suggest that cognition is maintained by functional reconfiguration of large-scale internetwork communications, which are partly altered by genetic risk factors and predict future domain-specific cognitive progression.

Ultra-short echo time (UTE) MRI with post-processing is a promising technique in bone imaging that produces a similar contrast to computed tomography (CT). Here, we propose a 3D slab-selective ultrashort echo time (UTE) sequence together with image post-processing to image bone structures in the lumbar spine. We also explore the intermodality agreement between the UTE and CT images. The lumbar spines of two healthy volunteers were imaged with 3D UTE using five different resolutions to determine the best imaging protocol. Then, four patients with low back pain were imaged with both the 3D UTE sequence and CT to investigate agreement between the imaging methods. Two other patients with low back pain were then imaged with the 3D UTE sequence and clinical conventional T1-weighted and T2-weighted fast spin-echo (FSE) MRI sequences for qualitative comparison. The 3D UTE sequence together with post-processing showed high contrast images of bone and high intermodality agreement with CT images. In conclusion, post-processed slab-selective UTE imaging is a feasible approach for highlighting bone structures in the lumbar spine and demonstrates significant anatomical correlation with CT images.

Blast-related mild traumatic brain injury (bmTBI) often leads to long-term sequalae, but diagnostic approaches are lacking due to insufficient knowledge about the predominant pathophysiology. This study aimed to build a diagnostic model for future verification by applying machine-learning based support vector machine (SVM) modeling to diffusion tensor imaging (DTI) datasets to elucidate white-matter features that distinguish bmTBI from healthy controls (HC). Twenty subacute/chronic bmTBI and 19 HC combat-deployed personnel underwent DTI. Clinically relevant features for modeling were selected using tract-based analyses that identified group differences throughout white-matter tracts in five DTI metrics to elucidate the pathogenesis of injury. These features were then analyzed using SVM modeling with cross validation. Tract-based analyses revealed abnormally decreased radial diffusivity (RD), increased fractional anisotropy (FA) and axial/radial diffusivity ratio (AD/RD) in the bmTBI group, mostly in anterior tracts (29 features). SVM models showed that FA of the anterior/superior corona radiata and AD/RD of the corpus callosum and anterior limbs of the internal capsule (5 features) best distinguished bmTBI from HCs with 89% accuracy. This is the first application of SVM to identify prominent features of bmTBI solely based on DTI metrics in well-defined tracts, which if successfully validated could promote targeted treatment interventions.

Deficient inhibitory control in Parkinson’s disease (PD) is often observed in situations requiring inhibition of impulsive or prepotent behaviors. Although activation of the right-hemisphere frontal-basal ganglia response inhibition network is partly altered in PD, disturbances in interactions of these regions are poorly understood, especially in patients without cognitive impairment. The present study investigated context-dependent connectivity of response inhibition regions in PD patients with normal cognition and control participants who underwent fMRI while performing a stop signal task. PD participants were tested off antiparkinsonian medication. To determine if functional disturbances depended on underlying brain structure, aberrant connectivity was correlated with brain volume and white-matter tissue diffusivity. We found no group differences in response inhibition proficiency. Yet the PD group showed functional reorganization in the long-range connectivity of inhibition regions, despite preserved within network connectivity. Successful inhibition in PD differed from the controls by strengthened connectivity of cortical regions, namely the right dorsolateral prefrontal cortex, pre-supplementary motor area and right caudal inferior frontal gyrus, largely with ventral and dorsal attention regions, but also the substantia nigra and default mode network regions. Successful inhibition in controls was distinguished by strengthened connectivity of the right rostral inferior frontal gyrus and subcortical inhibition nodes (right caudate, substantia nigra, and subthalamic nucleus). In both groups, the strength of context-dependent connectivity correlated with various indices of response inhibition performance. Mechanisms that may underlie aberrantly stronger context-specific connectivity include reduced coherence within reorganized systems, compensatory mechanisms, and/or the reorganization of intrinsic networks. In PD, but not controls, abnormally strengthened connectivity was linked to individual differences in underlying brain volumes and tissue diffusivity, despite no group differences in structural variables. The pattern of structural-functional associations suggested that subtle decreases in tissue diffusivity of underlying tracts and posterior cortical volumes may undermine the enhancement of normal cortical-striatal connectivity or cause strengthening in cortical-cortical connectivity. These novel findings demonstrate that functionally reorganized interactions of inhibition regions predates the development of inhibition deficits and clinically significant cognitive impairment in PD. We speculate that altered interactions of inhibition regions with attention-related networks and the dopaminergic system may presage future decline in inhibitory control.

A barrier in the diagnosis of mild traumatic brain injury (mTBI) stems from the lack of measures that are adequately sensitive in detecting mild head injuries. MRI and CT are typically negative in mTBI patients with persistent symptoms of post-concussive syndrome (PCS), and characteristic difficulties in sustaining attention often go undetected on neuropsychological testing, which can be insensitive to momentary lapses in concentration. Conversely, visual tracking strongly depends on sustained attention over time and is impaired in chronic mTBI patients, especially when tracking an occluded target. This finding suggests deficient internal anticipatory control in mTBI, the neural underpinnings of which are poorly understood. The present study investigated the neuronal bases for deficient anticipatory control during visual tracking in 25 chronic mTBI patients with persistent PCS symptoms and 25 healthy control subjects. The task was performed while undergoing magnetoencephalography (MEG), which allowed us to examine whether neural dysfunction associated with anticipatory control deficits was due to altered alpha, beta, and/or gamma activity. Neuropsychological examinations characterized cognition in both groups. During MEG recordings, subjects tracked a predictably moving target that was either continuously visible or randomly occluded (gap condition). MEG source-imaging analyses tested for group differences in alpha, beta, and gamma frequency bands. The results showed executive functioning, information processing speed, and verbal memory deficits in the mTBI group. Visual tracking was impaired in the mTBI group only in the gap condition. Patients showed greater error than controls before and during target occlusion, and were slower to resynchronize with the target when it reappeared. Impaired tracking concurred with abnormal beta activity, which was suppressed in the parietal cortex, especially the right hemisphere, and enhanced in left caudate and frontal–temporal areas. Regional beta-amplitude demonstrated high classification accuracy (92%) compared to eye-tracking (65%) and neuropsychological variables (80%). These findings show that deficient internal anticipatory control in mTBI is associated with altered beta activity, which is remarkably sensitive given the heterogeneity of injuries.

Post-traumatic stress disorder (PTSD) is a leading cause of sustained impairment, distress, and poor quality of life in military personnel, veterans, and civilians. Indirect functional neuroimaging studies using PET or fMRI with fear-related stimuli support a PTSD neurocircuitry model that includes amygdala, hippocampus, and ventromedial prefrontal cortex (vmPFC). However, it is not clear if this model can fully account for PTSD abnormalities detected directly by electromagnetic-based source imaging techniques in resting-state. The present study examined resting-state magnetoencephalography (MEG) signals in 25 active-duty service members and veterans with PTSD and 30 healthy volunteers. In contrast to the healthy volunteers, individuals with PTSD showed: 1) hyperactivity from amygdala, hippocampus, posterolateral orbitofrontal cortex (OFC), dorsomedial prefrontal cortex (dmPFC), and insular cortex in high-frequency (i.e., beta, gamma, and high-gamma) bands; 2) hypoactivity from vmPFC, Frontal Pole (FP), and dorsolateral prefrontal cortex (dlPFC) in high-frequency bands; 3) extensive hypoactivity from dlPFC, FP, anterior temporal lobes, precuneous cortex, and sensorimotor cortex in alpha and low-frequency bands; and 4) in individuals with PTSD, MEG activity in the left amygdala and posterolateral OFC correlated positively with PTSD symptom scores, whereas MEG activity in vmPFC and precuneous correlated negatively with symptom score. The present study showed that MEG source imaging technique revealed new abnormalities in the resting-state electromagnetic signals from the PTSD neurocircuitry. Particularly, posterolateral OFC and precuneous may play important roles in the PTSD neurocircuitry model.

Traumatic brain injury (TBI) is a leading cause of sustained impairment in military and civilian populations. However, mild TBI (mTBI) can be difficult to detect using conventional MRI or CT. Injured brain tissues in mTBI patients generate abnormal slow-waves (1–4 Hz) that can be measured and localized by resting-state magnetoencephalography (MEG). In this study, we develop a voxel-based whole-brain MEG slow-wave imaging approach for detecting abnormality in patients with mTBI on a single-subject basis. A normative database of resting-state MEG source magnitude images (1–4 Hz) from 79 healthy control subjects was established for all brain voxels. The high-resolution MEG source magnitude images were obtained by our recent Fast-VESTAL method. In 84 mTBI patients with persistent post-concussive symptoms (36 from blasts, and 48 from non-blast causes), our method detected abnormalities at the positive detection rates of 84.5%, 86.1%, and 83.3% for the combined (blast-induced plus with non-blast causes), blast, and non-blast mTBI groups, respectively. We found that prefrontal, posterior parietal, inferior temporal, hippocampus, and cerebella areas were particularly vulnerable to head trauma. The result also showed that MEG slow-wave generation in prefrontal areas positively correlated with personality change, trouble concentrating, affective lability, and depression symptoms. Discussion is provided regarding the neuronal mechanisms of MEG slow-wave generation due to deafferentation caused by axonal injury and/or blockages/limitations of cholinergic transmission in TBI. This study provides an effective way for using MEG slow-wave source imaging to localize affected areas and supports MEG as a tool for assisting the diagnosis of mTBI.

Background and Purpose: Traumatic brain injury (TBI) is a major source of health loss and disability worldwide. Accurate and timely diagnosis of TBI is critical for appropriate treatment and management of the condition. Neuroimaging plays a crucial role in the diagnosis and characterization of TBI. Computed tomography (CT) is the first-line diagnostic imaging modality typically utilized in patients with suspected acute mild, moderate and severe TBI. Radiology reports play a crucial role in the diagnostic process, providing critical information about the location and extent of brain injury, as well as factors that could prevent secondary injury. However, the complexity and variability of radiology reports can make it challenging for healthcare providers to extract the necessary information for diagnosis and treatment planning., Methods/results/conclusion: In this article, we report the efforts of an international group of TBI imaging experts to develop a clinical radiology report template for CT scans obtained in patients suspected of TBI and consisting of fourteen different subdivisions (CT technique, mechanism of injury or clinical history, presence of scalp injuries, fractures, potential vascular injuries, potential injuries involving the extra-axial spaces, brain parenchymal injuries, potential injuries involving the cerebrospinal fluid spaces and the ventricular system, mass effect, secondary injuries, prior or coexisting pathology)., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Introduction: Patients who are immunocompromised face an increased chance of severe COVID-19 infection compared with patients who are immunocompetent. However, vaccine efficacy for COVID-19 appears to be lower in patients who are immunocompromised. Tixagevimab-cilgavimab are monoclonal antibodies designed to enhance immune defense against COVID-19. Nevertheless, the safety and efficacy of tixagevimab-cilgavimab specifically in patients who are immunocompromised remains unknown., Methods: The authors conducted a retrospective case study of patients who were immunocompromised and received tixagevimab-cilgavimab between January 3, 2022 to July 31, 2022 at Kaiser Permanente Southern California. All patients were monitored for 180 days following tixagevimab-cilgavimab administration. Patients who were immunocompromised included those with solid tumors, hematologic malignancies, primary immunodeficiencies, recipients of solid organ or hematopoietic stem cell transplants, and patients undergoing treatment with immunosuppressive medications (eg, chemotherapy, high-dose corticosteroids, tumor necrosis factor blockers, and certain biologic agents)., Results: A total of 2352 patients who were immunocompromised were included in the study. Among them, 101 patients (4.3%) tested positive for COVID-19, and 13 patients (0.6%) required COVID-19-related hospital admissions. Notably, no deaths were reported within 180 days following tixagevimab-cilgavimab administration. Additionally, 4 patients (0.17%) sought same-day medical care after receiving tixagevimab-cilgavimab. Within 30 days, there were 39 non-COVID-19-related hospital admissions (1.7%) and within 7 days, 11 hospital admissions (0.5%) occurred after tixagevimab-cilgavimab administration., Discussion: Tixagevimab-cilgavimab demonstrated a low incidence of COVID-19 and COVID-19-related hospital admissions in patients who were immunocompromised, with no reported mortality. Furthermore, there were no significant adverse effects associated with the use of these monoclonal antibodies., Conclusion: Tixagevimab-cilgavimab exhibited a low incidence of COVID-19 and adverse effects in patients who were immunocompromised., Competing Interests: Conflicts of Interest None declared

Background: Solid organ transplant recipients (SOTr) are at increased risk for severe disease from coronavirus disease 2019 (COVID-19) compared with non-SOTr., Methods: We performed a retrospective cohort study between March 1, 2020, and March, 30, 2021, in an integrated healthcare system with 4.3 million members aged ≥18 y including 5126 SOTr. Comparisons in COVID-19 mortality, hospitalization, and incidence were made between SOTr and non-SOTr, and between different SOTr organs. Multivariate analysis was performed to identify risk factors for COVID-19 mortality and hospitalization., Results: There were 600 SOTr (kidney, liver, heart, and lung) with COVID-19. Per person-year incidence of COVID-19 among SOTr was 10.0% versus 7.6% among non-SOTr (P < 0.0001). Compared with uninfected SOTr, infected SOTr were older (57.1 ± 14.0 versus 45.7 ± 17.9 y, P < 0.001), predominantly Hispanic/Latino (58.8% versus 38.6%, P < 0.0001), hypertensive (77.0% versus 23.8%; P < 0.0001), and diabetic (49.6% versus 13.0%; P = 0.0009). Compared with non-SOTr, infected SOTr had higher hospitalization (39.5% versus 6.0%; P < 0.0001), intensive care unit admission (29.1% versus 15.5%; P < 0.0001), and mortality (14.7% versus 1.8%; P < 0.0001) from COVID-19. Older age (hazard ratio [HR], 1.07; 95% confidence interval [CI], 1.05-1.10), male gender (HR, 1.79; 95% CI, 1.11-2.86), and higher body mass index (HR, 1.04; 95% CI, 1.00-1.09; P = 0.047) were associated with increased mortality from COVID-19, whereas race, diabetes, and number/type of immunosuppressive medications were not. Among the different SOTr, COVID-19 mortality risk was lowest in liver recipients (HR, 0.34; 95% CI, 0.16-0.73) and highest in lung recipients (HR, 1.74; 95% CI, 0.68-4.42)., Conclusions: SOTr have higher rates of hospitalization and mortality from COVID-19 compared with the general population. Among the SOTr, the incidence and outcomes were distinct among different transplantation types., Competing Interests: The authors declare no funding or conflicts of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Aim: Colorectal cancer (CRC) is the third most deadly and fourth most common cancer worldwide. Early detection, resection, and appropriate surveillance of precursor polyps result in better outcomes. Colonoscopy is a safe, accurate, and effective tool for surveillance and follow-up of premalignant polyps. Recommended surveillance intervals are based on polyp, procedural, and patient-related factors. The United States Multi-Society Task Force (MSTF) on CRC publishes guidelines with periodic updates on surveillance. We sought to evaluate adherence to post-polypectomy surveillance guidelines by academic gastroenterologists at a high-volume center., Methods: One-year retrospective study evaluating compliance with post-polypectomy recommendations after average risk adult screening colonoscopies. Data was collected on number and size of polyps, quality of bowel prep, initial follow-up recommendations, polyp pathology, and follow-up recommendations. Correlation with the 2012 MSTF guidelines was also evaluated. Endoscopist experience was categorized as greater or less than 10 years of practice experience. Binomial regression was used to model the association between the providers' years of experience (<10 vs. >10) and the likelihood of agreement between initial assessment and post-pathology assessment., Results: There was a greater than 85% adherence to post-polypectomy surveillance guidelines, independent of endoscopist experience., Conclusion: There is a high level of adherence to post-polypectomy guidelines by practicing academic gastroenterologists independent of post-fellowship clinical experience., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: To describe our early experience using a contrast-enhanced ultrasound (CEUS) protocol for surveillance of hepatocellular carcinoma (HCC) at a semi-rural academic medical center., Methods: Retrospective, longitudinal study of the first 100 patients who underwent CEUS liver screening imaging over 2 years. Each patient underwent a standard of care abdominal ultrasound, which was checked with the radiologist, who searched for a focal lesion on the cine clips to target specifically with contrast. If none was present, the HCC contrast-enhanced screening protocol consisting of individual sweeps of the right and left lobes was performed from 0 to 60 s and 3-4 min post contrast-Lumason was utilized. Images, report details, and patient demographics were analyzed., Results: 66 men and 34 women (average age, 59 ± 13 years) were included. On average, the distance from patient's home to our institution was 39 miles (range 2-179 miles). The majority of our patients were covered under Private insurance (46%) with 43% covered by Medicare. CEUS exams on average took 35 min to complete. Lumason was administered in split doses for an average total of 5 mL per exam. Of the 10 lesions identified, there were five LI-RADS 3, two LI-RADS 4, one LI-RADS 5, two LI-RADS M, and one bland portal vein thrombus. There were no complications reported., Conclusion: This semi-rural single-center study demonstrates the feasibility of starting a HCC CEUS screening program. CEUS can be performed in conjunction with routine ultrasound imaging with added benefit of identifying and characterizing lesions in one setting., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Mild Traumatic Brain Injury (MTBI) patients with persistent headaches are known to have diminished supraspinal modulatory connectivity from their prefrontal cortices. Repetitive transcranial magnetic stimulation (rTMS) is able to alleviate MTBI-related headache (MTBI-HA). This functional magnetic resonance imaging (fMRI) study assessed supraspinal correlates associated with the headache analgesic effect of rTMS at left prefrontal cortex (LPFC), hypothesizing real rTMS would significantly increase modulatory functions at LPFC in comparison to sham treatment. Subjects with MTBI-HA were randomized to receive either real or sham rTMS treatments and subjected to pre- and post-treatment resting state and evoked heat-pain fMRI as described in a prior study. Real rTMS consisted of 2000 pulses delivered at 10 Hz and 80% of the resting motor threshold at left dorsolateral prefrontal cortex, whereas sham treatment was delivered with same figure-of-eight coil turned 180 degrees. Follow-up fMRI was performed one-week post-treatment. All fMRI data was processed using BrainVoyager QX Software. 14 subjects receiving real and 12 subjects receiving sham treatments completed the study. The REAL group demonstrated significant (P < 0.02) decreases in headache frequency and intensity at one week following treatment. fMRI scans in the REAL group showed increased evoked heat pain activity (P < 0.002) and resting functional connectivity (P < 0.0001) at the LPFC after rTMS. Neither this significant analgesic effect nor these fMRI findings were seen in the sham group. Sham treatment was, however, associated with a decrease in resting state activity at the LPFC (P < 0.0001). This study correlates the demonstrated analgesic effect of rTMS in the treatment of MTBI-HA with enhanced supraspinal functional connectivity in the left prefrontal cortex, which is known to be involved in "top-down" pain inhibition along the descending midbrain-thalamic-cingulate pathway. Trial Registration: This study was registered on September 24, 2013, on ClinicalTrials.gov with the identifier: NCT01948947. https://clinicaltrials.gov/ct2/show/NCT01948947 .

Background: Conversion from calcineurin inhibitor (CNI)-based to belatacept-based immunosuppression has become common; however, numerous protocols have emerged in lieu of a standardized protocol. The purpose of this study was to characterize belatacept conversion protocols from multiple centers and observe outcomes., Methods: This was a retrospective study that included Kaiser Permanente Southern California members. The primary outcome was rejection 6 months after conversion and secondary outcomes included change in serum creatinine and graft loss., Results: Seventy-eight patients were included. Thirteen distinct protocols were identified from 8 different transplant centers. Protocols varied by initial dose, induction schedule, and CNI taper. The observed rate of rejection was 6%. There was a trend toward an association of rejection with lower tacrolimus exposure at the time of conversion and lower mycophenolic acid dosing postconversion. Graft survival was 88% and patient survival was 94%. There was a significant improvement in creatinine after conversion. Those with early conversions and creatinine >2.0 mg/dL at the time of conversion had the best response., Conclusions: A large variety of belatacept conversion protocols were identified. Protocols were defined by the initial dose, induction regimen, and CNI taper. Rejection rates were low and may be influenced by exposure to maintenance immunosuppression during and after conversion. Most patients showed stabilization and improvement in creatinine postconversion, with the largest effect in those with an early conversion and serum creatinine >2.0 mg/dL., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Emerging evidence suggests mild traumatic brain injury related headache (MTBI-HA) is a form of neuropathic pain state. Previous supraspinal mechanistic studies indicate patients with MTBI-HA demonstrate a dissociative state with diminished levels of supraspinal prefrontal pain modulatory functions and enhanced supraspinal sensory response to pain in comparison to healthy controls. However, the relationship between supraspinal pain modulatory functional deficit and severity of MTBI-HA is largely unknown. Understanding this relationship may provide enhanced levels of insight about MTBI-HA and facilitate the development of treatments. This study assessed pain related supraspinal resting states among MTBI-HA patients with various headache intensity phenotypes with comparisons to controls via functional magnetic resonance imaging (fMRI). Resting state fMRI data was analyzed with self-organizing-group-independent-component-analysis in three MTBI-HA intensity groups (mild, moderate, and severe) and one control group (n = 16 per group) within a pre-defined supraspinal pain network based on prior studies. In the mild-headache group, significant increases in supraspinal function were observed in the right premotor cortex (T = 3.53, p < 0.001) and the left premotor cortex (T = 3.99, p < 0.0001) when compared to the control group. In the moderate-headache group, a significant (T = -3.05, p < 0.01) decrease in resting state activity was observed in the left superior parietal cortex when compared to the mild-headache group. In the severe-headache group, significant decreases in resting state supraspinal activities in the right insula (T = -3.46, p < 0.001), right premotor cortex (T = -3.30, p < 0.01), left premotor cortex (T = -3.84, p < 0.001), and left parietal cortex (T = -3.94, p < 0.0001), and an increase in activity in the right secondary somatosensory cortex (T = 4.05, p < 0.0001) were observed when compared to the moderate-headache group. The results of the study suggest that the increase in MTBI-HA severity may be associated with an imbalance in the supraspinal pain network with decline in supraspinal pain modulatory function and enhancement of sensory/pain decoding.

Chronic diffuse body pain is unequivocally highly prevalent in Veterans who served in the 1990-91 Persian Gulf War and diagnosed with Gulf War Illness (GWI). Diminished motor cortical excitability, as a measurement of increased resting motor threshold (RMT) with transcranial magnetic stimulation (TMS), is known to be associated with chronic pain conditions. This study compared RMT in Veterans with GWI related diffuse body pain including headache, muscle and joint pain with their military counterparts without GWI related diffuse body pain. Single pulse TMS was administered over the left motor cortex, using anatomical scans of each subject to guide the TMS coil, starting at 25% of maximum stimulator output (MSO) and increasing in steps of 2% until a motor response with a 50 µV peak to peak amplitude, defined as the RMT, was evoked at the contralateral flexor pollicis brevis muscle. RMT was then analyzed using Repeated Measures Analysis of Variance (RM-ANOVA). Veterans with GWI related chronic headaches and body pain (N = 20, all males) had a significantly (P < 0.001) higher average RMT (% ± SD) of 77.2% ± 16.7% compared to age and gender matched military controls (N = 20, all males), whose average was 55.6% ± 8.8%. Veterans with GWI related diffuse body pain demonstrated a state of diminished corticomotor excitability, suggesting a maladaptive supraspinal pain modulatory state. The impact of this observed supraspinal functional impairment on other GWI related symptoms and the potential use of TMS in rectifying this abnormality and providing relief for pain and co-morbid symptoms requires further investigation.Trial registration: This study was registered on January 25, 2017, on ClinicalTrials.gov with the identifier: NCT03030794. Retrospectively registered. https://clinicaltrials.gov/ct2/show/NCT03030794 .

Reported is the synthesis of carboxylic acids, symmetrical ketones, and unsymmetrical ketones with selectivity achieved by exploiting the differential reactivity of sodium methyl carbonate with Grignard and organolithium reagents.

The MRI appearance of intraventricular neoplasms is often nonspecific, however knowledge of patient age and tumor location facilitates the formulation of a differential diagnosis. Imaging and pertinent clinical features of the following intraventricular neoplasms are reviewed: ependymoma, subependymoma, central neurocytoma, subependymal giant cell tumor, choroid plexus tumors, medulloblastoma, meningioma, chordoid glioma, rosette-forming glioneuronal tumor, central nervous system lymphoma, and metastasis., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objective: Persistent mild traumatic brain injury related headache (MTBI-HA) represents a neuropathic pain state. This study tested the hypothesis that repetitive transcranial magnetic stimulation (rTMS) at the left prefrontal cortex can alleviate MTBI-HA and associated neuropsychological dysfunctions., Methods and Materials: Veterans with MTBI-HA were randomized to receive four sessions of either real (REAL group) or sham (SHAM group) high frequency rTMS delivered at 10 Hz, 80% of resting motor threshold and 2000 pulses per session at >24 and <72 hours apart. Pre-treatment, post-treatment 1-week and 4-week headache and neuropsychological assessments were conducted., Results: Twenty nine out of forty-four consented subjects completed the study. A two-factor (visit × treatment) repeated measures ANOVA showed a significant (p = 0.002, F = 11.63, df = 1) interaction for the average daily persistent headache intensity with the REAL group exhibiting a significant (p < 0.0001) average reduction (±SD) of 25.3 ± 16.8% and 23.0 ± 17.7% reduction in their numerical rating scale at the one-week and four-week post-treatment assessments in comparison to <1 ± 11.7% and 2.3 ± 14.5% reduction found in the SHAM group. In addition, a significant (p < 0.01) 50% and 57% reduction was found in the prevalence of persistent headache in the REAL group at the one-week and four-week assessments in comparison to 7% and 20% reduction found in the SHAM group. Furthermore, the REAL group demonstrated a significant (p = 0.033) improvement (from 22.3 ± 6.4 at pre-treatment to 19.0 ± 5.0 at post-treatment one-week) in the Hamilton Rating Scale for Depression score, while the SHAM group's score remained largely unchanged (from 25.33 ± 8.43 to 24.64 ± 5.03) in the same time frame. This trend of improvement, although not statistically significant, continues to the post-treatment four-week assessment., Conclusion: A short-course rTMS at the left DLPFC can alleviate MTBI-HA symptoms and provide a transient mood enhancing benefit. Further studies are required to establish a clinical protocol balancing both treatment efficacy and patient compliance., (© 2017 International Neuromodulation Society.)

Background: The occurrence of debilitating chronic persistent (24/7) headache after mild traumatic brain injury represents a central neuropathic pain state. Previous studies suggest that this chronic headache state can be attributed to altered supraspinal modulatory functional connectivity in both resting and evoked pain states. Abnormalities in the myelin sheaths along the supraspinal superior longitudinal fasciculus and anterior thalamic radiation are frequently associated with alteration in pain modulation related to functional connectivity deficit with the prefrontal cortex. This study assessed the correlated axonal injury-related white matter tract abnormality underlying these previously observed prefrontal functional connectivity deficits by comparing the fractional anisotropy, axial diffusivity, and radial diffusivity of brain white matter in patients with mild traumatic brain injury-related headache to healthy controls., Result: Diffusion tensor imaging data from patients ( N = 12, average age ±  SD = 35.0 ± 8.0 years old, 10 male) with mild traumatic brain injury-headache were compared with images acquired from healthy controls. The mild traumatic brain injury cohort demonstrated two areas of significant ( P < 0.01, F value >16, cluster size >50 voxels) white matter tract abnormalities closely related to pain affective and modulatory functions in (1) the left superior longitudinal fasciculus which connects the prefrontal cortices with the parietal cortices and (2) the right anterior thalamic radiation connecting the prefrontal cortices with the anterior cingulate cortex. In addition, a significant ( P < 0.01) decrease in axial diffusivity and increase in radial diffusivity at the superior longitudinal fasciculus cluster were noted in the mild traumatic brain injury cohort., Conclusion: The identified white matter tract abnormalities may represent a state of Wallerian degeneration which correlates with the functional connectivity deficit in pain modulation and can contribute to the development of the chronic persistent headache in the patients with mild traumatic brain injury.

Background: Chronic pain conditions are highly prevalent in patients with mild traumatic brain injury. Supraspinal diffuse axonal injury is known to dissociate brain functional connectivity in these patients. The effect of this dissociated state on supraspinal pain network is largely unknown. A functional magnetic resonance imaging study was conducted to compare the supraspinal pain network in patients with mild traumatic brain injury to the gender and age-matched healthy controls with the hypothesis that the functional connectivities of the medial prefrontal cortices, a supraspinal pain modulatory region to other pain-related sensory discriminatory and affective regions in the mild traumatic brain injury subjects are significantly reduced in comparison to healthy controls., Results: The mild traumatic brain injury group (N = 15) demonstrated significantly (P < 0.01, cluster threshold > 150 voxels) less activities in the thalamus, pons, anterior cingulate cortex, insula, dorsolateral prefrontal cortex, and medial prefrontal cortices than the healthy control group (N = 15). Granger Causality Analyses (GCA) indicated while the left medial prefrontal cortices of the healthy control group cast a noticeable degree of outward (to affect) causality inference to multiple pain processing related regions, this outward inference pattern was not observed in the mild traumatic brain injury group. On the other hand, only patients' bilateral anterior cingulate cortex received multiple inward (to be affected) causality inferences from regions including the primary and secondary somatosensory cortices and the inferior parietal lobe. Resting state functional connectivity analyses indicated that the medial prefrontal cortices of the mild traumatic brain injury group demonstrated a significantly (P < 0.01, F = 3.6, cluster size > 150 voxels) higher degree of functional connectivity to the inferior parietal lobe, premotor and secondary somatosensory cortex than the controls. Conversely, the anterior cingulate cortex of the healthy group demonstrated significantly (P < 0.01, F = 3.84, cluster size > 150 voxels) less degree of functional connectivities to the inferior parietal lobe and secondary somatosensory cortex than their mild traumatic brain injury counterparts., Conclusions: In short, the current study demonstrates that patients with mild traumatic brain injury and headaches appear to have an altered state of supraspinal modulatory and affective functions related to pain perception., (© The Author(s) 2016.)

Objective: Headache is one of the most common debilitating chronic pain conditions in either active or retired military personnel with mild traumatic brain injury (MTBI). This study assessed the effect of repetitive transcranial magnetic stimulation (rTMS) in alleviating MTBI-related headache (MTBI-HA)., Materials and Method: Veterans with MTBI-HA were randomized to receive either real rTMS (REAL group) at 10 hz for a total of 2000 pulses divided into 20 trains with one-sec inter-train interval or sham rTMS (SHAM group) at the left motor cortex (LMC) with brain magnetic resonance imaging neuronavigation guidance. Pretreatment, posttreatment one-week and four-week headache and neuropsychological assessments were conducted., Result: Thirty veterans were screened and twenty four (21 men and 3 women with average year-old ± SD at 14.3 ± 12.6) subjects' data were analyzed. A two-factor (visit × treatment) repeated measures analysis of variance (RM-ANOVA) indicated a close to significant (p = 0.06) trend of interaction between pretreatment and posttreatment one-week assessment with the intensity of the persistent daily headache decreasing from 5.7 ± 1.9 to 2.2 ± 2.7 and 4.6 ± 1.3 to 3.5 ± 2.0 for the REAL and SHAM groups, respectively. Subsequent analyses indicated REAL group demonstrated a significantly (p = 0.041) higher % of reduction in persistent headache intensity than the SHAM group (56.3 ± 48.2% vs.15.4 ± 43.6%) at the posttreatment one-week assessment and the trend continued to the four-week assessment. Overall, a significantly (p = 0.035) higher percentage of the subjects in the REAL group (58.3%) demonstrated at least a 50% headache intensity reduction at posttreatment one-week assessment compared with the SHAM group (16.6%). The overall composite score of functionally debilitating headache exacerbation is significantly (p = 0.017) reduced in REAL group at the posttreatment four-week assessment in comparison with the SHAM group. No major sustained change in neuropsychological assessments was noted., Conclusion: The studied rTMS protocol appears to be a clinically feasible and effective treatment option in managing MTBI-HA., (© 2015 International Neuromodulation Society.)

Background: Headache is one of the most common debilitating chronic pain conditions in patients with mild traumatic brain injury. Conventional pharmacological treatments have not been shown to be effective in alleviating debilitating mild traumatic brain injury related headaches (MTBI-HA). Therefore, the development of an innovative non-invasive therapy in managing MTBI-HA is needed in the field of pain management. Repetitive transcranial magnetic stimulation (rTMS) utilizes a basic electromagnetic coupling principle in which a rapid discharge of electrical current is converted into dynamic magnetic flux, allowing the induction of a localized current in the brain for neuromodulation. The treatment is currently FDA approved for treating depression in the United States. Recent meta-analysis studies have implicated its usage in chronic pain management., Objective: The objective of the prospective case series is to assess the potential application of rTMS in alleviating MTBI-HA., Study Design: A prospective evaluation was conducted in patients with established diagnoses of MTBI-HA and treated with neuronavigational guided rTMS., Setting: The study was conducted at the Veteran Administration San Diego Healthcare System where over 400 patients with MTBI were being evaluated annually by the Rehabilitation Medicine Service. A fraction of this patient population was referred and evaluated in the Anesthesia Pain Clinic for the consideration of rTMS for their headaches., Methods: A prospective case series was conducted with human subject protection committee approval. Patients with established diagnoses of MTBI and constant headaches rated at = 4 on a 0 - 10 Numerical Rating Pain Scale (NRPS), and on stable headache medication regimens were selected to receive the treatment. Four sessions of rTMS were delivered to specific areas of cortices over a 2-month period. Patients' average intensities of lingering constant headaches (defined as duration of headache lasting more than 48 hours), and the average frequency (number of severe headache episodes per day), intensity (NRPS), and duration (hours) of headache exacerbations were assessed before and after the rTMS treatment protocol., Results: Six men (average age of 50) with MTBI-HA received the rTMS treatment protocol. Average pre and post-rTMS constant headache scores (± SD) on the NRPS were 5.50 (± 1.38) and 2.67 (± 1.75), respectively, with an average post-rTMS headache intensity reduction of 53.05% (± 19.90). The average headache exacerbation frequency (episodes per week) was reduced by 78.97% (±19.88) with 2 patients reporting complete cessation of severe headache episodes. For those (N = 4) with persistent headache exacerbations, the average duration and intensity of these exacerbations were reduced by 50.0% and 31.7%, respectively., Limitations: This prospective evaluation provides the initial insight that rTMS may be beneficial in alleviating a debilitating chronic pain condition in patients with MTBI-HA. More controlled randomized studies should be conducted to validate its efficacy. Other co-existing cognitive and mood dysfunction should be assessed as well., Conclusions: rTMS offers a non-invasive treatment option for MTBI-HA. The tested treatment protocol was well tolerated by the patients and can be adopted for future randomized controlled studies in further validating the treatment efficacy.

On October 21, 2015, the Hawaii Department of Health (HDOH) was notified of a positive dengue immunoglobulin M (IgM) antibody result in a woman residing on Hawaii Island (also known as the Big Island). The patient had no history of travel off the island, and other family members reported having similar signs and symptoms, which consisted of fever, headache, myalgias and arthralgias, and a generalized erythematous rash. HDOH initiated an investigation to identify any additional cases and potential exposure sources. On October 24, HDOH received report of a group of mainland U.S. visitors who had traveled together on Hawaii Island, including several who had developed a febrile illness. Additionally, on October 27, HDOH was notified of an unrelated person, also on Hawaii Island, with a positive dengue IgM result. As of November 26, 2015, HDOH had identified 107 laboratory-confirmed cases of dengue fever, with dates of onset ranging from September 11 to November 18, 2015.

The move to a low-carbon economy has generated renewed interest in microalgae for the production of biofuels with the potential mutual benefit of wastewater treatment. However, harvesting has been identified as a limiting factor to the economic viability of this process. This paper explores the harvesting of microalgae using high-pressure gas without the addition of coagulants. Coagulation of microalgae under high-pressure gas was found to be an efficient method to separate algae from suspension. The critical coagulation pressures (CCPs) for H(2) and CO(2) were determined to be 6.1 and 6.2 MPa, respectively. The CO(2)-induced decrease in solution pH positively influenced coagulation rates, without appearing to affect the CCP. This approach could be beneficial for the economic removal of microalgae from solution for the production of both biofuels and biomedical compounds without the addition of non-environmentally friendly chemicals., (© 2015 The Author(s).)

In resting-state functional magnetic resonance imaging (fMRI), the temporal correlation between spontaneous fluctuations of the blood oxygenation level dependent (BOLD) signal from different brain regions is used to assess functional connectivity. However, because the BOLD signal is an indirect measure of neuronal activity, its complex hemodynamic nature can complicate the interpretation of differences in connectivity that are observed across conditions or subjects. For example, prior studies have shown that caffeine leads to widespread reductions in BOLD connectivity but were not able to determine if neural or vascular factors were primarily responsible for the observed decrease. In this study, we used source-localized magnetoencephalography (MEG) in conjunction with fMRI to further examine the origins of the caffeine-induced changes in BOLD connectivity. We observed widespread and significant (p < 0.01) reductions in both MEG and fMRI connectivity measures, suggesting that decreases in the connectivity of resting-state neuro-electric power fluctuations were primarily responsible for the observed BOLD connectivity changes. The MEG connectivity decreases were most pronounced in the beta band. By demonstrating the similarity in MEG and fMRI based connectivity changes, these results provide evidence for the neural basis of resting-state fMRI networks and further support the potential of MEG as a tool to characterize resting-state connectivity.

Purpose: To investigate anterior chamber parameters and biometric factors associated with degree of angle opening after laser peripheral iridotomy (LPI) for narrow angles., Methods: In this prospective cohort study, patients with narrow angles who were scheduled for LPI were recruited. Anterior chamber parameters by anterior segment coherence tomography (ASOCT) under dark conditions were compared before and after LPI. Only the right eye was used for analysis if both eyes were eligible. Measurements performed by customized software included anterior chamber depth, iris area, angle opening distance at 500 µm (AOD500) anterior to the scleral spur, iris thickness at 750 µm from sclera spur (IT750), trabecular-iris space area 500 (TISA500), and iris curvature (I-Curv). Univariate and multiple regression analyses were performed to determine the predictive factors of angle opening after LPI., Results: Eighty-one patients with narrow angles were prospectively recruited in this study. The AOD500 increased significantly from 0.128 ± 0.081 mm (before) to 0.209 ± 0.087 mm (after) in the nasal quadrant, and from 0.103 ± 0.067 mm (before) to 0.197 ± 0.071 mm (after) in the temporal quadrant (p < 0.001 for both nasal and temporal). I-Curv decreased significantly after LPI (p < 0.001). Significant increase was noted in TISA500 before and after LPI (p < 0.001). In the multiple regression model, increase in AOD500 was positively correlated with age (standardized β = 0.283, p = 0.007) and I-Curv (standardized β = 0.239, p = 0.021), and was negatively correlated with preoperative iris area (standardized β = -0.292, p = 0.015)., Conclusions: In this hospital-based study on the results of LPI for narrow angle subjects, statistically significant independent predictors of anterior chamber angle widening after LPI were older age, smaller iris area, and steeper iris.

Purpose: To compare the optic nerve head (ONH) and retinal nerve fiber layer (RNFL) in eyes with narrow angles and normal intraocular pressure (IOP) to normal control eyes., Materials and Methods: A total of 70 eyes of 52 subjects with narrow angles and 40 eyes of 34 normal subjects were enrolled. Narrow angle eyes were defined as the following: (i) the pigmented trabecular meshwork was not visible for ≥ 180° on gonioscopy, (ii) untreated IOP ≤ 21 mmHg, (iii) no peripheral anterior synechiae (PAS) was observed, and (iv) optic discs were without glaucomatous changes, defined as neuroretinal rim thinning, focal notching, disc hemorrhages, or focal RNFL defects. ONH and peripapillary RNFL imaging were obtained with Heidelberg Retina Tomograph (HRT II) and Fourier-domain optical coherence tomography (RTVue OCT)., Results: No significant difference was found in mean age between the two groups (p = 0.06), but the narrow angle group had significantly more women (p = 0.04). The narrow angle group had significantly higher IOP and smaller mean angle width (both p < 0.001). Vertical cup-to-disc ratio (VCDR) was significantly larger in the narrow angle group (p = 0.02). In visual field (VF) results, the mean deviation (MD) was significantly lower and pattern standard deviation (PSD) was significantly higher in the narrow angle group (both p < 0.001). After adjusting for disc area, the RNFL thickness of the inferior-temporal region was significantly thinner in the narrow angle group (135 ± 21.7 µm) compared with normal group (149 ± 22.1 µm, p < 0.01). This finding remained significant after Bonferroni correction for multiple comparisons. Smaller angle width was a significant predictor of RNFL thinning in the inferior-temporal region (p < 0.001)., Conclusion: These data suggest that eyes with narrow angles may develop glaucomatous optic nerve damage in the absence of IOP elevation during office hours.

Purpose: To evaluate anterior chamber biometric factors associated with the degree of angle widening and intraocular pressure (IOP) reduction after phacoemulsification., Setting: University of California, San Francisco, California, USA., Design: Case series., Methods: Anterior chamber parameters obtained by anterior segment coherence tomography were compared preoperatively and 3 months postoperatively. Measurements included the angle opening distance 500 μm anterior to the scleral spur (AOD500), trabecular-iris space area 500 μm from the scleral spur (TISA500), iris curvature (I-Curv), anterior chamber angle (ACA), trabecular-iris space area, anterior chamber volume, anterior chamber width, and lens vault (LV)., Results: The study enrolled 73 eyes. The mean patient age was 77.45 years ± 7.84 (SD); 65.75% of patients were women. From preoperatively to 3 months postoperatively, the mean AOD500 increased significantly (0.254 ± 0.105 to 0.433 ± 0.108 mm) and the mean IOP decreased significantly (14.97 ± 3.35 to 12.62 ± 3.37 mm Hg) (P<.001). The reduction in IOP was correlated with the increase in AOD500 (r = 0.240, P=.041) and preoperative LV (r = 0.235, P=.045). After adjusting for related factors, AOD500 widening was positively correlated with LV (β = 0.458, P=.044) and I-Curv (β = 0.235, P=.043) and negatively correlated with preoperative TISA500 (β = -0.269, P=.025) and ACA (β = -0.919, P=.027)., Conclusions: Surgically induced AOD widening was significantly correlated with anterior chamber biometric factors. Preoperative LV appears to be a significant factor in angle widening and IOP reduction after phacoemulsification., (Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Objective: To determine the association of changes in anterior chamber angle and anterior chamber depth (ACD) with intraocular pressure (IOP) reduction after uncomplicated phacoemulsification., Methods: In this prospective study, subjects underwent phacoemulsification with foldable lens implantation. Anterior chamber angle grading of 2 or less (Shaffer grading) in 3 or all quadrants was considered narrow angle (NA). Anterior segment optical coherence tomography and tonometry were performed preoperatively and 10 days and 1, 3, and 6 months after surgery. The ACD and angle opening distance at 500 μm anterior to the scleral spur (AOD500) were assessed from anterior segment optical coherence tomography., Results: Data were collected from 63 eyes that underwent cataract surgery. Twenty-six eyes were classified as having NA. Before surgery, the mean (SD) AOD500 and ACD in the NA group were 0.179 (0.014) mm and 2.23 (0.07) mm, respectively. Six months after surgery, the mean (SD) AOD500 and ACD in the NA group were 0.389 (0.025) mm and 3.75 (0.05) mm, respectively. The postoperative IOP was reduced significantly in both groups. We found that each 0.1-mm increase in AOD500 corresponded to a mean (SD) 0.42 (0.18)-mm Hg decrease in IOP (P < .001) in the NA group and 0.32 (0.16) mm Hg (P = .046) in the OA group., Conclusions: Postoperative reduction in IOP was proportional to the increase in angle in both groups, but the IOP reduction per 0.1-mm increase in AOD500 in NA eyes was greater than that in OA eyes.

Carbon nanotubes (CNTs) were deposited from a chlorosulfonic superacid solution onto PET substrates by a filtration/transfer method. The sheet resistance and transmission (at 550 nm) of the films were 60 Ω/sq and 90.9% respectively, which corresponds to a DC conductivity of 12,825 S cm(-1) and a DC/optical conductivity ratio of 64.1. This is the highest DC conductivity reported for CNT thin films to date, and attributed to both the high quality of the CNT material and the exfoliation/doping by the superacid. This work demonstrates that CNT transparent films have not reached the conductivity limit; continued improvements will enable these films to be used as the transparent electrode for applications in solid state lighting, LCD displays, touch panels, and photovoltaics.

Objective: We integrated multicenter, real-time (RTi) reverse transcription polymerase chain reaction (RT-PCR) screening into a statewide laboratory algorithm for influenza surveillance and response., Methods: Each of three sites developed its own testing strategy and was challenged with one randomized and blinded panel of 50 specimens previously tested for respiratory viruses. Following testing, each participating laboratory reported its results to the Hawaii State Department of Health, State Laboratories Division for evaluation and possible discrepant analysis., Results: Two of three laboratories reported a 100% sensitivity and specificity, resulting in a 100% positive predictive value and a 100% negative predictive value (NPV) for influenza type A. The third laboratory showed a 71% sensitivity for influenza type A (83% NPV) with 100% specificity. All three laboratories were 100% sensitive and specific for the detection of influenza type B. Discrepant analysis indicated that the lack of sensitivity experienced by the third laboratory may have been due to the analyte-specific reagent probe used by that laboratory. Use of a newer version of the product with a secondary panel of 20 specimens resulted in a sensitivity and specificity of 100%., Conclusions: All three laboratories successfully verified their ability to conduct clinical testing for influenza using diverse nucleic acid extraction and RTi RT-PCR platforms. Successful completion of the verification by all collaborating laboratories paved the way for the integration of those facilities into a statewide laboratory algorithm for influenza surveillance and response.

Auditory information communicated through vocalizations, music, or sounds in the environment is commonly used to orient and direct attention to different locations in extrapersonal space. The neural networks subserving attention to auditory space remain poorly understood in comparison to our knowledge about attention in the visual system. The present study investigated whether a parietal-prefrontal right-hemisphere network controls endogenous orienting and reorienting of attention to the location of sounds just as it does for visual-spatial information. Seventeen healthy adults underwent event-related functional magnetic resonance imaging (FMRI) while performing an endogenous auditory orienting task, in which peripheral cues correctly (valid) or incorrectly (invalid) specified the location of a forthcoming sound. The results showed that a right precuneus and bilateral temporal-frontal network mediated the reorienting of auditory attention at both short and long stimulus onset asynchronies (SOAs). In contrast, the more automatic stage of auditory reorienting at the shorter SOA was associated with activation in a bilateral inferior parietal-frontal oculomotor network. These findings suggest that the reorienting of auditory attention is generally supported by a similar inferior parietal-frontal network as visual attention, but in both hemispheres. However, peripheral auditory cues also appear to elicit an automatic orienting response to the spatial location of a sound followed by a period of reduced processing of information that occurs in the same location later in time.

Purpose: The objective of our study was to determine noninvasively whether metabolic dysfunction is present in focal areas of interictal electrophysiologic abnormality and whether metabolic dysfunction correlates with frequency of spiking., Methods: We used a prospective, power analysis-driven, age-matched design to study 20 subjects with nonlesional temporal lobe epilepsy by using magnetoencephalography (MEG) and proton magnetic resonance spectroscopy (1H-MRS). MEG was used to localize the source area of interictal spikes. 1H-MRS measured integrated peak areas for N-acetyl compounds (NAA) and choline-containing compounds (Cho) in both hippocampi, the MEG spike zone, and the region contralateral to the MEG spike zone in all subjects. 1H-MRS was performed in seven controls., Results: Fifteen of 20 subjects had a lower NAA/Cho ratio in the MEG spike zone compared with the contralateral homologous region. NAA/Cho was significantly decreased in the MEG spike zone (p < 0.01). NAA/Cho ratios were not significantly different between the hippocampus ipsilateral and contralateral to the spike activity, or from control hippocampi. NAA/Cho ratios did not correlate with spike frequency., Conclusions: Metabolic dysfunction is present in focal areas of interictal spiking in nonlesional temporal lobe epilepsy. These findings confirm that functional abnormalities can be detected in vivo in radiographically normal-appearing cortex exhibiting abnormal excitability.