Longitudinal cerebral perfusion in presymptomatic genetic frontotemporal dementia: GENFI results.

INTRODUCTION: Effective longitudinal biomarkers that track disease progression are needed to characterize the presymptomatic phase of genetic frontotemporal dementia (FTD). We investigate the utility of cerebral perfusion as one such biomarker in presymptomatic FTD mutation carriers. METHODS: We investigated longitudinal profiles of cerebral perfusion using arterial spin labeling magnetic resonance imaging in 42 C9orf72, 70 GRN, and 31 MAPT presymptomatic carriers and 158 non-carrier controls. Linear mixed effects models assessed perfusion up to 5 years after baseline assessment. RESULTS: Perfusion decline was evident in all three presymptomatic groups in global gray matter. Each group also featured its own regional pattern of hypoperfusion over time, with the left thalamus common to all groups. Frontal lobe regions featured lower perfusion in those who symptomatically converted versus asymptomatic carriers past their expected age of disease onset. DISCUSSION: Cerebral perfusion is a potential biomarker for assessing genetic FTD and its genetic subgroups prior to symptom onset. HIGHLIGHTS: Gray matter perfusion declines in at-risk genetic frontotemporal dementia (FTD). Regional perfusion decline differs between at-risk genetic FTD subgroups . Hypoperfusion in the left thalamus is common across all presymptomatic groups. Converters exhibit greater right frontal hypoperfusion than non-converters past their expected conversion date. Cerebral hypoperfusion is a potential early biomarker of genetic FTD.

Single Cell Transcriptome of Stress Vulnerability Network in mouse Prefrontal Cortex.

Increased vulnerability to stress is a major risk factor for the manifestation of several mood disorders, including major depressive disorder (MDD). Despite the status of MDD as a significant donor to global disability, the complex integration of genetic and environmental factors that contribute to the behavioral display of such disorders has made a thorough understanding of related etiology elusive. Recent developments suggest that a brain-wide network approach is needed, taking into account the complex interplay of cell types spanning multiple brain regions. Single cell RNA-sequencing technologies can provide transcriptomic profiling at the single-cell level across heterogenous samples. Furthermore, we have previously used local field potential oscillations and machine learning to identify an electrical brain network that is indicative of a predisposed vulnerability state. Thus, this study combined single cell RNA-sequencing (scRNA-Seq) with electrical brain network measures of the stress-vulnerable state, providing a unique opportunity to access the relationship between stress network activity and transcriptomic changes within individual cell types. We found especially high numbers of differentially expressed genes between animals with high and low stress vulnerability brain network activity in astrocytes and glutamatergic neurons but we estimated that vulnerability network activity depends most on GABAergic neurons. High vulnerability network activity included upregulation of microglia and mitochondrial and metabolic pathways, while lower vulnerability involved synaptic regulation. Genes that were differentially regulated with vulnerability network activity significantly overlapped with genes identified as having significant SNPs by human GWAS for depression. Taken together, these data provide the gene expression architecture of a previously uncharacterized stress vulnerability brain state, enabling new understanding and intervention of predisposition to stress susceptibility.

Cadaveric Prehospital Amputation: Which Reciprocating Saw Blade Offers the Most Efficient Amputation.

OBJECTIVE: Field amputations are a low-frequency, high-risk procedure. Many prehospital personnel utilize the reciprocating saw. This study compares the efficiency, speed, and degree of tissue damage of different reciprocating saw blades found commercially. METHODS: Amputations were performed on two human cadavers at different levels of the upper and lower extremities. Four different blades were used, each with a different teeth-per-inch (TPI) design. The amputations were timed, blade temperature was recorded, subjective operator effort was obtained, amount of splatter was evaluated, and an orthopedic physician evaluated the extent of tissue damage and operating room repair difficulty. RESULTS: The blade with fourteen TPI was superior in overall speed to complete the amputations at 1.07 seconds per one centimeter of tissue (SD = 0.49 seconds) and had the lowest fail rate (0/8 amputations). The three TPI, six TPI, and ten TPI blades all required a "rescue" technique and were slower. The blade with fourteen TPI caused the least amount of tissue damage and was deemed the easiest to repair. Secondary outcomes demonstrated the fourteen TPI blade had generated the least amount of heat and produced the least amount of splatter. All blades had a perceived effort of "easy" to complete the amputation. CONCLUSION: While all blades were able to achieve an amputation, the overall recommendation is use of a fourteen TPI blade. It did not require any rescue techniques, provided the most straightforward amputation to repair, had the least amount of biohazard splatter and temperature increase, and was the fastest blade overall.

Diagnostic accuracy of telestroke consultation: a Louisiana based tele-network experience.

Background and purpose: Telestroke has grown significantly since its implementation. Despite growing utilization, there is a paucity of data regarding the diagnostic accuracy of telestroke to distinguish between stroke and its mimics. We aimed to evaluate diagnostic accuracy of telestroke consultations and explore the characteristics of misdiagnosed patients with a focus on stroke mimics. Methods: We conducted a retrospective study of all the consultations in our Ochsner Health's TeleStroke program seen between April 2015 and April 2016. Consultations were classified into one of three diagnostic categories: stroke/transient ischemic attack, mimic, and uncertain. Initial telestroke diagnosis was compared with the final diagnosis post review of all emergency department and hospital data. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+) and negative likelihood ratio (LR-) for diagnosis of stroke/TIA versus mimic were calculated. Area under receiver-operating characteristic curve (AUC) analysis to predict true stroke was performed. Bivariate analysis based on the diagnostic categories examined association with sex, age, NIHSS, stroke risk factors, tPA given, bleeding after tPA, symptom onset to last known normal, symptom onset to consult, timing in the day, and consult duration. Logistic regression was performed as indicated by bivariate analysis. Results: Eight hundred and seventy-four telestroke evaluations were included in our analysis. Accurate diagnosis through teleneurological consultation was seen in 85% of which 532 were strokes (true positives) and 170 were mimics (true negatives). Sensitivity, specificity, PPV, NPV were 97.8, 82.5, 93.7 and 93.4%, respectively. LR+ and LR- were 5.6 and 0.03. AUC (95% CI) was 0.9016 (0.8749-0.9283). Stroke mimics were more common with younger age and female gender and in those with less vascular risk factors. LR revealed OR (95% CI) of misdiagnosis for female gender of 1.9 (1.3-2.9). Lower age and lower NIHSS score were other predictors of misdiagnosis. Conclusion: We report high diagnostic accuracy of the Ochsner Telestroke Program in discriminating stroke/TIA and stroke mimics, with slight tendency towards over diagnosis of stroke. Female gender, younger age and lower NIHSS score were associated with misdiagnosis.

Rasch analyses of the Quick Inventory of Depressive Symptomatology Self-Report in neurodegenerative and major depressive disorders.

Background: Symptoms of depression are present in neurodegenerative disorders (ND). It is important that depression-related symptoms be adequately screened and monitored in persons living with ND. The Quick Inventory of Depressive Symptomatology Self-Report (QIDS-SR) is a widely-used self-report measure to assess and monitor depressive severity across different patient populations. However, the measurement properties of the QIDS-SR have not been assessed in ND. Aim: To use Rasch Measurement Theory to assess the measurement properties of the Quick Inventory of Depressive Symptomatology Self-Report (QIDS-SR) in ND and in comparison to major depressive disorder (MDD). Methods: De-identified data from the Ontario Neurodegenerative Disease Research Initiative (NCT04104373) and Canadian Biomarker Integration Network in Depression (NCT01655706) were used in the analyses. Five hundred and twenty participants with ND (Alzheimer's disease or mild cognitive impairment, amyotrophic lateral sclerosis, cerebrovascular disease, frontotemporal dementia and Parkinson's disease) and 117 participants with major depressive disorder (MDD) were administered the QIDS-SR. Rasch Measurement Theory was used to assess measurement properties of the QIDS-SR, including unidimensionality and item-level fit, category ordering, item targeting, person separation index and reliability and differential item functioning. Results: The QIDS-SR fit well to the Rasch model in ND and MDD, including unidimensionality, satisfactory category ordering and goodness-of-fit. Item-person measures (Wright maps) showed gaps in item difficulties, suggesting poor precision for persons falling between those severity levels. Differences between mean person and item measures in the ND cohort logits suggest that QIDS-SR items target more severe depression than experienced by the ND cohort. Some items showed differential item functioning between cohorts. Conclusion: The present study supports the use of the QIDS-SR in MDD and suggest that the QIDS-SR can be also used to screen for depressive symptoms in persons with ND. However, gaps in item targeting were noted that suggests that the QIDS-SR cannot differentiate participants falling within certain severity levels. Future studies would benefit from examination in a more severely depressed ND cohort, including those with diagnosed clinical depression.

The Brain Medicine Clinic: two cases highlighting the advantages of integrative care.

BACKGROUND: Current assessment and management models often do not adequately address the many aspects of managing complex brain disorders involving disordered affect, behaviour and cognition (ABC). A more collaborative model of care, where several specialties can jointly assess and manage patients with complex brain disorders, is gaining attention. AIMS: In this case report, we present two cases that highlight the benefits of the 'brain medicine' clinical model. METHOD: The Brain Medicine Clinic employs an integrated clinical model in which psychiatrists and neurologists provide integrated interdisciplinary assessments of patients with complex brain disorders, leading to comprehensive assessment. We describe the clinical model and the trajectories of two patients with complex brain disorders seen in this clinic. In these case descriptions, we explain how the brain medicine clinical approach leads to an improved patient experience. RESULTS: The Brain Medicine Clinic assessments resulted in a neurobiopsychosocial formulation of symptoms and, consequently, holistic individualised treatment plans for two patients with complex brain disorders. This approach to patients' conditions emerges from the understanding that there are multifactorial causes of brain disorders at the social, cultural, psychological and biological level. CONCLUSIONS: Integrated interdisciplinary assessments allow for tailored treatment plans for individuals experiencing complex brain disorders, while creating efficiencies for the patient and the healthcare system.

The Brain Medicine Fellowship: A Competency-Based Training Program to Treat Complex Brain Disorders.

PROBLEM: Complex brain disorders involve symptoms in the domains of affect, behavior, and cognition. It is increasingly recognized that there is a need for a novel type of physician who can treat individuals with these conditions in an interdisciplinary fashion to best address their complexity. Few training programs have focused on the education of such practitioners. APPROACH: The authors outline the development and practices of the Brain Medicine Fellowship, an innovative, competency-based fellowship program at the University of Toronto Temerty Faculty of Medicine that accepts trainees from multiple brain medicine-related specialty training programs to develop expertise in integrative assessment and treatment of complex brain disorders. The authors describe how brain medicine competencies were generated, the current assessment process, and the seminal clinical experience associated with the fellowship-the Brain Medicine Clinic-and explain how it exemplifies brain medicine in action. OUTCOMES: The first fellow was registered from July 2019 to December 2020. As of December 2022, 3 fellows have entered the program, with 3 more anticipated to begin in July 2023. More than 26 supervisors are associated with the fellowship, who offer a diversity of experiences for fellows to choose from in developing their individualized learning plans. The Brain Medicine Fellowship not only fosters the development of a novel type of clinician (a brain medicine specialist) but also is innovative in its educational design as one of the first nonsurgical fellowships to implement competency-based medical education and has resulted in original clinical programming in the form of the Brain Medicine Clinic, which benefits patients and their caregivers. NEXT STEPS: The development of the Brain Medicine Fellowship continues with competency refinement and translation into entrustable professional activities and constituent milestones. A comprehensive program evaluation will be completed by 2025.

Investigating changes in cognition associated with the use of CPAP in cognitive impairment and dementia: A retrospective study.

STUDY OBJECTIVES: To characterize the impact of CPAP use on cognition in a clinical cohort with obstructive sleep apnea (OSA) and cognitive impairment due to neurodegenerative or vascular etiologies after controlling for baseline sleepiness. METHODS: We retrospectively analyzed data from 171 patients with cognitive impairment and an OSA diagnosis confirmed with in-laboratory polysomnography or home sleep apnea testing (mean age 69.8 ± 10.6; 66% male) who were eligible to use CPAP. Baseline and follow-up Epworth Sleepiness Score (ESS), Montreal Cognitive Assessment (MoCA), and Mini-Mental Status Examination (MMSE) were obtained from clinical and research visits conducted before and after CPAP initiation. Good CPAP adherence was defined as CPAP use ≥4 h/night, for 7 days/week at follow-up. Associations between CPAP adherence and follow-up cognitive scores were analyzed using multivariable linear mixed-effects models. RESULTS: After adjusting for age, sex, body mass index, baseline ESS, duration of CPAP therapy, relevant comorbidities and the random effect of research study cohort, good CPAP adherence (compared to poor CPAP adherence or no use of CPAP) for a duration of 2-12 months was associated with a 2.3-point (1.2-3.3 95% CI) higher follow-up MoCA score (p < 0.001) and a 1.2-point (0.3-2.3 95% CI) higher follow-up MMSE score (p = 0.01). CONCLUSIONS: In patients with OSA and cognitive impairment due to a neurodegenerative or vascular etiology, use of CPAP is associated with improved cognitive outcomes. The findings of this study may aid in motivating patients to use CPAP and support future randomized controlled trials in this area.

Students' awareness of the student health center's sexual health services at a southeast public university.

Objective: To determine whether university students are aware of the sexual health services offered by the student health center. Participants: 522 undergraduate students at a southeast public university. Methods: Students were given a list of 19 sexual health services and tests and were instructed that for each one to check "offered," "not offered," or "I'm not sure." Results: Students were generally unaware that the health center offered testing for a variety of sexually transmitted infections (13-27.4% aware), the Gardasil vaccine for human papillomavirus (HPV) (15.5% aware), the IUD (8.8% aware), emergency contraception (18.6% aware), and breast (24.9% aware) and pelvic examinations (16.5% aware). The only exceptions were for free male condoms (63% aware) and women's awareness of birth control pills (55.3% aware) and pregnancy testing (50.3% aware). Nearly half the students were not aware that parents/guardians could not obtain health center medical records without the student's permission. Conclusions: Student health centers cannot be effective in reducing unwanted pregnancies and the spread of STIs if students are unaware of the services provided. Health centers must do a better job of educating students.

A male steroid controls female sexual behaviour in the malaria mosquito.

Insects, unlike vertebrates, are widely believed to lack male-biased sex steroid hormones1. In the malaria mosquito Anopheles gambiae, the ecdysteroid 20-hydroxyecdysone (20E) appears to have evolved to both control egg development when synthesized by females2 and to induce mating refractoriness when sexually transferred by males3. Because egg development and mating are essential reproductive traits, understanding how Anopheles females integrate these hormonal signals can spur the design of new malaria control programs. Here we reveal that these reproductive functions are regulated by distinct sex steroids through a sophisticated network of ecdysteroid-activating/inactivating enzymes. We identify a male-specific oxidized ecdysteroid, 3-dehydro-20E (3D20E), which safeguards paternity by turning off female sexual receptivity following its sexual transfer and activation by dephosphorylation. Notably, 3D20E transfer also induces expression of a reproductive gene that preserves egg development during Plasmodium infection, ensuring fitness of infected females. Female-derived 20E does not trigger sexual refractoriness but instead licenses oviposition in mated individuals once a 20E-inhibiting kinase is repressed. Identifying this male-specific insect steroid hormone and its roles in regulating female sexual receptivity, fertility and interactions with Plasmodium parasites suggests the possibility for reducing the reproductive success of malaria-transmitting mosquitoes.

Use of Knives and Multitools to Perform a Cadaveric Limb Amputation.

BACKGROUND: An austere field amputation can be a life-saving procedure for an entrapped patient when standard equipment is not available or operable. The objective of this study was to use hand tools to perform cadaveric amputations in < 2 minutes. METHODS: Timed guillotine amputation of the extremities on three cadavers was attempted using four available hand tools: a multitool, a rescue tool, a hunting knife, and a fixedblade knife. The primary outcome was successful amputation of the extremity in < 2 minutes. RESULTS: Amputation success was different among the tools. The multitool amputated 78% of attempts; the hunting knife, 67%; the rescue knife, 56%; and the fixed-blade knife, 44%. The distal tibia/fibula and radius/ ulna were amputated successfully in 100% of attempts, whereas none of the tools could amputate the femur. The multitool received the best subjective ranking - 1.4 (p = .001) - by amputators, with the fixed-blade knife receiving the worst score. CONCLUSIONS: In the rare circumstance that an emergent field amputation requires a hand tool, the multitool is a capable instrument for a distal extremity amputation.

Mark-release-recapture of male Aedes aegypti (Diptera: Culicidae): Use of rhodamine B to estimate movement, mating and population parameters in preparation for an incompatible male program.

Rapid advances in biological and digital support systems are revolutionizing the population control of invasive disease vectors such as Aedes aegypti. Methods such as the sterile and incompatible insect techniques (SIT/IIT) rely on modified males to seek out and successfully mate with females, and in doing so outcompete the wild male population for mates. Currently, these interventions most frequently infer mating success through area-wide population surveillance and estimates of mating competitiveness are rare. Furthermore, little is known about male Ae. aegypti behaviour and biology in field settings. In preparation for a large, community scale IIT program, we undertook a series of mark- release-recapture experiments using rhodamine B to mark male Ae. aegypti sperm and measure mating interactions with females. We also developed a Spatial and Temporally Evolving Isotropic Kernel (STEIK) framework to assist researchers to estimate the movement of individuals through space and time. Results showed that ~40% of wild females captured daily were unmated, suggesting interventions will need to release males multiple times per week to be effective at suppressing Ae. aegypti populations. Males moved rapidly through the landscape, particularly when released during the night. Although males moved further than what is typically observed in females of the species, survival was considerably lower. These unique insights improve our understanding of mating interactions in wild Ae. aegypti populations and lay the foundation for robust suppression strategies in the future.

Modification to Neurology Residency Training: The Toronto Neurology COVID-19 Pandemic Experience.

We describe the University of Toronto Adult Neurology Residency Program's early experiences with and response to the coronavirus disease 2019 pandemic, including modifications to the provision of neurologic care while upholding neurology education and safety. All academic and many patient-related activities were virtualized. This maintained physical distancing while creating a city-wide videoconference-based teaching curriculum, expanding the learning opportunities to trainees at all academic sites. Furthermore, we propose a novel split-team model to promote resident safety through physical distancing of teams and to establish a capacity to rapidly adapt to redeployment, service needs, and trainee illness. Finally, we developed a unique protected code stroke framework to safeguard staff and trainees during hyperacute stroke assessments in this pandemic. Our shared experiences highlight considerations for contingency planning, maintenance of education, sustainability of team members, and promotion of safe neurologic care. These interventions serve to promote trainee safety, wellness, and resiliency.

A mating-induced reproductive gene promotes Anopheles tolerance to Plasmodium falciparum infection.

Anopheles mosquitoes have transmitted Plasmodium parasites for millions of years, yet it remains unclear whether they suffer fitness costs to infection. Here we report that the fecundity of virgin and mated females of two important vectors-Anopheles gambiae and Anopheles stephensi-is not affected by infection with Plasmodium falciparum, demonstrating that these human malaria parasites do not inflict this reproductive cost on their natural mosquito hosts. Additionally, parasite development is not impacted by mating status. However, in field studies using different P. falciparum isolates in Anopheles coluzzii, we find that Mating-Induced Stimulator of Oogenesis (MISO), a female reproductive gene strongly induced after mating by the sexual transfer of the steroid hormone 20-hydroxyecdysone (20E), protects females from incurring fecundity costs to infection. MISO-silenced females produce fewer eggs as they become increasingly infected with P. falciparum, while parasite development is not impacted by this gene silencing. Interestingly, previous work had shown that sexual transfer of 20E has specifically evolved in Cellia species of the Anopheles genus, driving the co-adaptation of MISO. Our data therefore suggest that evolution of male-female sexual interactions may have promoted Anopheles tolerance to P. falciparum infection in the Cellia subgenus, which comprises the most important malaria vectors.

JNK signaling regulates oviposition in the malaria vector Anopheles gambiae.

The reproductive fitness of the Anopheles gambiae mosquito represents a promising target to prevent malaria transmission. The ecdysteroid hormone 20-hydroxyecdysone (20E), transferred from male to female during copulation, is key to An. gambiae reproductive success as it licenses females to oviposit eggs developed after blood feeding. Here we show that 20E-triggered oviposition in these mosquitoes is regulated by the stress- and immune-responsive c-Jun N-terminal kinase (JNK). The heads of mated females exhibit a transcriptional signature reminiscent of a JNK-dependent wounding response, while mating-or injection of virgins with exogenous 20E-selectively activates JNK in the same tissue. RNAi-mediated depletion of JNK pathway components inhibits oviposition in mated females, whereas JNK activation by silencing the JNK phosphatase puckered induces egg laying in virgins. Together, these data identify JNK as a potential conduit linking stress responses and reproductive success in the most important vector of malaria.

Author Correction: Efficient production of male Wolbachia-infected Aedes aegypti mosquitoes enables large-scale suppression of wild populations.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

The Virtual Neurologic Exam: Instructional Videos and Guidance for the COVID-19 Era.

OBJECTIVE: To outline features of the neurologic examination that can be performed virtually through telemedicine platforms (the virtual neurological examination [VNE]), and provide guidance for rapidly pivoting in-person clinical assessments to virtual visits during the COVID-19 pandemic and beyond. METHODS: The full neurologic examination is described with attention to components that can be performed virtually. RESULTS: A screening VNE is outlined that can be performed on a wide variety of patients, along with detailed descriptions of virtual examination maneuvers for specific scenarios (cognitive testing, neuromuscular and movement disorder examinations). CONCLUSIONS: During the COVID-19 pandemic, rapid adoption of virtual medicine will be critical to provide ongoing and timely neurological care. Familiarity and mastery of a VNE will be critical for neurologists, and this article outlines a practical approach to implementation.

Efficient production of male Wolbachia-infected Aedes aegypti mosquitoes enables large-scale suppression of wild populations.

The range of the mosquito Aedes aegypti continues to expand, putting more than two billion people at risk of arboviral infection. The sterile insect technique (SIT) has been used to successfully combat agricultural pests at large scale, but not mosquitoes, mainly because of challenges with consistent production and distribution of high-quality male mosquitoes. We describe automated processes to rear and release millions of competitive, sterile male Wolbachia-infected mosquitoes, and use of these males in a large-scale suppression trial in Fresno County, California. In 2018, we released 14.4 million males across three replicate neighborhoods encompassing 293 hectares. At peak mosquito season, the number of female mosquitoes was 95.5% lower (95% CI, 93.6-96.9) in release areas compared to non-release areas, with the most geographically isolated neighborhood reaching a 99% reduction. This work demonstrates the high efficacy of mosquito SIT in an area ninefold larger than in previous similar trials, supporting the potential of this approach in public health and nuisance-mosquito eradication programs.