Venous thromboembolism with renal infarct due to paradoxical embolism.

Paradoxical thromboembolism has variable presentation depending on site of embolisation. An African-American man in his 40s presented with severe abdominal pain, watery stools and exertional dyspnoea. At presentation, he was tachycardic and hypertensive.

HIV-associated Burkitt lymphoma: outcomes from a US-UK collaborative analysis.

Data addressing prognostication in patients with HIV related Burkitt lymphoma (HIV-BL) currently treated remain scarce. We present an international analysis of 249 (United States: 140; United Kingdom: 109) patients with HIV-BL treated from 2008 to 2019 aiming to identify prognostic factors and outcomes. With a median follow up of 4.

An informational reference on anthrax for first responders.

Anthrax was widely discussed in the media several years ago during the American Anthrax attacks. Despite a less-ened interest in the subject today, anthrax still poses a threat to the United States government and its people. This article looks at publically available data and resources in an effort to combine current information into one easy to ready docu-ment.

Burkitt lymphoma in the modern era: real-world outcomes and prognostication across 30 US cancer centers.

We examined adults with untreated Burkitt lymphoma (BL) from 2009 to 2018 across 30 US cancer centers. Factors associated with progression-free survival (PFS) and overall survival (OS) were evaluated in univariate and multivariate Cox models. Among 641 BL patients, baseline features included the following: median age, 47 years; HIV+, 22%; Eastern Cooperative Oncology Group (ECOG) performance status (PS) 2 to 4, 23%; >1 extranodal site, 43%; advanced stage, 78%; and central nervous system (CNS) involvement, 19%.

An informational reference on anthrax for first responders.

Anthrax was widely discussed in the media several years ago during the American Anthrax attacks. Despite a lessened interest in the subject today, anthrax still poses a threat to the United States government and its people. This article looks at publically available data and resources in an effort to combine current information into one easy to ready document.

Sacral anatomical interspace landmark for lumbar puncture in pregnancy: A randomized trial.

Objective: To determine whether the sacral anatomical interspace landmark (SAIL) technique is more accurate than the classic intercristal line (ICL) technique in pregnant patients and to assess the percentage of clinical determinations above the third lumbar vertebra.

Methods: In this prospective, randomized, open-label trial, there were 110 singleton pregnant patients with gestational age greater than 37 weeks included. Selection procedure was a convenience sample of pregnant patients who presented for office visits or vaginal or cesarean delivery between March 15 and July 31, 2018, at a single-center obstetric tertiary care university hospital.

Lumbar neuraxial procedures in thrombocytopenic patients across populations: A systematic review and meta-analysis.

Introduction: There is currently no consensus regarding the minimum threshold platelet count to ensure safe neuraxial procedures. Numerous reports describe the safe performance of lumbar punctures in severely thrombocytopenic patients but reports of neuraxial anesthetic procedures in thrombocytopenic patients are limited. To date, the focus on specific populations in contemporary reviews has failed to include any actual hematoma cases.

School-Based Bullying and Teen Dating Violence Prevention Laws: Overlapping or Distinct?

The most recent legislative attempts to curb violence in schools have been school-based dating violence prevention laws. In the previous decade, there was an increase in legislation designed to prevent bullying in schools; these laws now exist in 50 states. However, most anti-bullying laws provide an expansive definition of bullying that includes any type of peer aggression, harassment, or teen dating violence (TDV).

Vascular compliance limits during sleep deprivation and recovery sleep.

Study Objectives: Our previous studies showed that evoked hemodynamic responses are smaller during wake compared to sleep; suggesting neural activity is associated with vascular expansion and decreased compliance. We explored whether prolonged activity during sleep deprivation may exacerbate vascular expansion and blunt hemodynamic responses.

Design: Evoked auditory responses were generated with periodic 65 dB speaker clicks over a 72-h period and measured with cortical electrodes.

Sleep: a synchrony of cell activity-driven small network states.

We posit a bottom-up sleep-regulatory paradigm in which state changes are initiated within small networks as a consequence of local cell activity. Bottom-up regulatory mechanisms are prevalent throughout nature, occurring in vastly different systems and levels of organization. Synchronization of state without top-down regulation is a fundamental property of large collections of small semi-autonomous entities.

Neurovascular saturation thresholds under high intensity auditory stimulation during wake.

Coupling between neural activity and hemodynamic responses is important in understanding brain function, interpreting brain-imaging signals, and assessing pathological conditions. Tissue state is a major factor in neurovascular coupling and may alter the relationship between neural and hemodynamic activity. However, most neurovascular-coupling studies are performed under anesthetized or sedated states which may have severe consequences on coupling mechanisms.

State-dependent changes in cortical gain control as measured by auditory evoked responses to varying intensity stimuli.

Study Objectives: Auditory evoked potential (AEP) components correspond to sequential activation of brain structures within the auditory pathway and reveal neural activity during sensory processing. To investigate state-dependent modulation of stimulus intensity response profiles within different brain structures, we assessed AEP components across both stimulus intensity and state.

Design: We implanted adult female Sprague-Dawley rats (N = 6) with electrodes to measure EEG, EKG, and EMG.

Assessment of network states: local hemodynamics.

Neural activity utilizes energy resources and requires replenishment of metabolites through vascular dilation. During wake, cortical neurons usually have depolarized membrane potentials and exhibit frequent spontaneous action potentials, requiring an increased metabolic delivery to activated tissue and causing blood vessels to dilate. Quiet sleep (QS) is characterized by alternating membrane potential between a depolarized and hyperpolarized state.

Evoked electrical and cerebral vascular responses during sleep and following sleep deprivation.

Neuronal activity elicits vascular dilation, delivering additional blood and metabolites to the activated region. With increasing neural activity, vessels stretch and may become less compliant. Most functional imaging studies assume that limits to vascular expansion are not normally reached except under pathological conditions, with the possibility that metabolism could outpace supply.

Cortical evoked responses associated with arousal from sleep.

Study Objective: To determine if low-level intermittent auditory stimuli have the potential to disrupt sleep during 24-h recordings, we assessed arousal occurrence to varying stimulus intensities. Additionally, if stimulus-generated evoked response potential (ERP) components provide a metric of underlying cortical state, then a particular ERP structure may precede an arousal.

Design: Physiological electrodes measuring EEG, EKG, and EMG were implanted into 5 adult female Sprague-Dawley rats.

Precision rodent whisker stimulator with integrated servo-locked control and displacement measurement.

We developed a high speed voice coil based whisker stimulator that delivers precise deflections of a single whisker or group of whiskers in a repeatable manner. The device is miniature, quiet, and inexpensive to build. Multiple stimulators fit together for independent stimulation of four or more whiskers.

Rat psychomotor vigilance task with fast response times using a conditioned lick behavior.

Investigations into the physiological mechanisms of sleep control require an animal psychomotor vigilance task (PVT) with fast response times (<300 ms). Rats provide a good PVT model since whisker stimulation produces a rapid and robust cortical evoked response, and animals can be trained to lick following stimulation. Our prior experiments used deprivation-based approaches to maximize motivation for operant conditioned responses.

Physiological markers of local sleep.

Substantial evidence suggests that brain regions that have been disproportionately used during waking will require a greater intensity and/or duration of subsequent sleep. For example, rats use their whiskers in the dark and their eyes during the light, and this is manifested as a greater magnitude of electroencephalogram (EEG) slow-wave activity in the somatosensory and visual cortex during sleep in the corresponding light and dark periods respectively. The parsimonious interpretation of such findings is that sleep is distributed across local brain regions and is use-dependent.

Complete optical neurophysiology: toward optical stimulation and recording of neural tissue.

Direct optical methods to stimulate and record neural activity provide artifact-free, noninvasive, and noncontact neurophysiological procedures. For stimulation, focused mid-infrared light alters membrane potential and activates individual neural processes. Simultaneous intrinsic scattered light parameters, including birefringence changes, can record neural activity with signals similar to potentiometric dyes.

State-dependent auditory evoked hemodynamic responses recorded optically with indwelling photodiodes.

Implantable optical technologies provide measurements of cerebral hemodynamic activity from freely behaving animals without movement constraint or anesthesia. In order to study state-dependent neural evoked responses and the consequential hemodynamic response, we simultaneously measured EEG and scattered light changes in chronically implanted rats. Recordings took place under freely behaving conditions, allowing us to compare the evoked responses across wake, sleep, and anesthetized states.

Mechanisms underlying state dependent surface-evoked response patterns.

Cortical evoked response potentials (ERPs) display a rich set of waveforms that are both context and state dependent. However, the mechanisms that underlie state dependent ERP patterns are unclear. Determining those mechanisms through analysis of single trial ERP waveform signatures may provide insight into the regulation of cortical column state and the roles that sleep plays in cortical function.

In vitro and in vivo noise analysis for optical neural recording.

Laser diodes (LD) are commonly used for optical neural recordings in chronically recorded animals and humans, primarily due to their brightness and small size. However, noise introduced by LDs may counteract the benefits of brightness when compared to low-noise light-emitting diodes (LEDs). To understand noise sources in optical recordings, we systematically compared instrument and physiological noise profiles in two recording paradigms.