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The piriform cortex is recognized as highly epileptogenic in rodents, yet its electrophysiological role in human epilepsy remains understudied. Recent surgical outcomes have suggested potential benefits in resecting the piriform cortex for cases of medial temporal lobe epilepsy. However, little is known about its electrophysiological activity in human epilepsy. This case-series study aimed to explore the electrophysiological role of the piriform cortex within the epileptogenic network among patients with suspected temporal lobe epilepsy. Participants were recruited from Emory University Hospital or Children's Healthcare of Atlanta, with non-lesional frontotemporal or temporal lobe hypotheses, undergoing stereoelectroencephalographic studies. Specifically, focus was placed on patients with one or more electrode contacts in the piriform cortex. Primary objectives included determining piriform cortex involvement within the electrophysiologically defined epileptogenic network and assessing the effects of electrical stimulation. Twenty-two patients were included in the study. Notably, only one patient exhibited piriform cortex involvement at seizure onset, associated with an olfactory aura. Two patients showed early piriform cortex involvement, while others displayed late or no involvement. Electrical stimulation of the piriform cortex induced after-discharges in three patients and replicated a habitual seizure in one. These findings present a contrast to surgical outcome studies, suggesting that the piriform cortex may not typically play a significant role in the epileptogenic network among patients with non-lesional temporal lobe epilepsy.

Rates of cigarette smoking in people with HIV (PWH) are two to three times higher than in people without HIV. Nicotine is metabolized by CYP2A6 and the nicotine metabolite ratio (NMR; 3-hydroxycotinine/cotinine) is a measure of nicotine clearance. Higher NMR has been observed in PWH and is associated with lower quit rates. Efavirenz, a mainstay antiretroviral therapy (ART) globally, partially upregulates its own metabolism through CYP2A6. We hypothesized that efavirenz also upregulates nicotine metabolism by CYP2A6, resulting in a higher NMR, and switching to non-efavirenz ART would decrease the NMR, potentially leading to improved quit rates. We compared the NMR during and after efavirenz use among PWH in a longitudinal, multisite cohort. Eligibility criteria included: (i) active cigarette smoking, (ii) ART switched from efavirenz-based to non-efavirenz-based regimen, (iii) plasma available at pre- and post-ART switch, and (iv) viral suppression during study period. Plasma cotinine and 3-hydroxycotinine were measured by liquid chromatography-tandem mass spectrometry. T-tests compared the NMR on and off efavirenz. Samples were collected between 2010 and 2019 in 72 PWH. The mean NMR difference after switching to a non-efavirenz-based regimen was -0.24 (SD: 0.37, P

BackgroundSmoking contributes to significant morbidity and mortality in people with HIV. People with HIV have relatively high nicotine metabolism rates, as measured by the nicotine metabolite ratio (NMR, 3-hydroxycotinine/cotinine). A higher NMR is associated with difficulty quitting smoking. We hypothesized that HIV infection might upregulate nicotine metabolism.SettingA retrospective study of male current smokers in the Multicenter AIDS Cohort Study who HIV seroconverted between 1985 and 1993.MethodsEligibility included having plasma stored before and after confirmed HIV seroconversion and current tobacco use. Samples were selected from the closest available visits before (median 3.3 months) and after (median 9.4 months) seroconversion. Antiretroviral therapy use was exclusionary. Cotinine and 3-hydroxycotinine were measured using liquid chromatography-tandem mass spectrometry. We compared NMR from plasma pre-HIV and post-HIV infection using signed-rank tests. We targeted a sample size of 71 pairs to achieve 80% power to detect a 0.1 unit increase in NMR with P = 0.05.ResultsWe analyzed paired samples from 78 participants; the median age was 34.5 years [interquartile range (IQR 29-40 years)]. The median NMR pre-HIV and post-HIV was 0.45 (IQR 0.32-0.54) and 0.46 (IQR 0.34-0.56), respectively. The median change in NMR postseroconversion was +0.01 (IQR -0.05, +0.09), P = 0.25. Stratification of median change in NMR by timing between samples or time since HIV seroconversion did not alter this finding.ConclusionsAcquiring HIV had no measurable effect on NMR. We postulate that upregulation of the NMR may be due to direct pharmacologic effects of HIV medications or metabolic changes in response to HIV infection.

We report a case study of a surgical candidate, a 51-year-old woman with left temporal lobe epilepsy, who failed a left injection intracarotid amobarbital procedure (e.g., Wada test), scoring 0 of 8 items. This raised concerns for postoperative memory decline. However, the patient was uninterested in a neuromodulatory approach and wished to be reconsidered for surgery. A stereotactic laser amygdalohippocampotomy (SLAH) was considered, encouraging the need for an alternative test to evaluate risk of memory decline. We developed a novel approach to testing memory during stimulation of a depth electrode implanted in the hippocampus, i.e., an electric Wada. During multiple stimulation trials across a range of amplitudes, the patient scored up to 8 of 8 items, which suggested strong contralateral memory support. The surgical team proceeded with a radiofrequency ablation and a subsequent SLAH. The patient remains seizure-free at 12 months post SLAH with no evidence of verbal or visuospatial memory decline based on a post-surgical neuropsychological battery. We believe that this case study provides a proof of concept for the feasibility and possible utility of an electric version of the Wada procedure. Future studies are needed to develop an optimal paradigm and to validate this approach.

BACKGROUND AND OBJECTIVES: To determine the association between surgical lesions of distinct gray and white structures and connections with favorable postoperative seizure outcomes. METHODS: Patients with drug-resistant temporal lobe epilepsy (TLE) from 3 epilepsy centers were included. We employed a voxel-based and connectome-based mapping approach to determine the association between favorable outcomes and surgery-induced temporal lesions. Analyses were conducted controlling for multiple confounders, including total surgical resection/ablation volume, hippocampal volumes, side of surgery, and site where the patient was treated. RESULTS: The cohort included 113 patients with TLE (54 women; 86 right-handed; mean age at seizure onset 16.5 years [SD 11.9]; 54.9% left) who were 61.1% free of disabling seizures (Engel Class 1) at follow-up. Postoperative seizure freedom in TLE was associated with (1) surgical lesions that targeted the hippocampus as well as the amygdala-piriform cortex complex and entorhinal cortices; (2) disconnection of temporal, frontal, and limbic regions through loss of white matter tracts within the uncinate fasciculus, anterior commissure, and fornix; and (3) functional disconnection of the frontal (superior and middle frontal gyri, orbitofrontal region) and temporal (superior and middle pole) lobes. DISCUSSION: Better postoperative seizure freedom is associated with surgical lesions of specific structures and connections throughout the temporal lobes. These findings shed light on the key components of epileptogenic networks in TLE and constitute a promising source of new evidence for future improvements in surgical interventions. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for patients with TLE, postoperative seizure freedom is associated with surgical lesions of specific temporal lobe structures and connections.

Introduction: Neuromodulation is an important treatment modality for patients with drug-resistant epilepsy who are not candidates for resective or ablative procedures. However, randomized controlled trials and real-world studies reveal that a subset of patients will experience minimal reduction or even an increase in seizure frequency after neuromodulation. We describe our experience with patients who undergo a second intracranial neuromodulation procedure after unsatisfactory initial response to intracranial neuromodulation. Methods: We performed a retrospective chart review to identify all patients who had undergone deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT) or responsive neurostimulation (RNS), followed by additional intracranial neuromodulatory procedures, with at least 12 months of follow-up. Demographic and clinical data, including seizure frequencies, were collected. Results: All patients had temporal lobe epilepsy. Six patients were treated with concurrent ANT DBS and temporal lobe RNS, and 3 patients transitioned between neuromodulation systems. Of the patients treated concurrently with ANT DBS and temporal lobe RNS, 5 of the 6 patients experienced additional reduction in seizure frequency after adding a second neuromodulation system. Of the patients who switched between neuromodulation modalities, all patients experienced further reduction in seizure frequency. Conclusions: For patients who do not experience adequate benefit from initial therapy with ANT DBS or temporal lobe RNS, the addition of a neuromodulation system or switching to a different form of neuromodulation may allow for additional reduction in seizure frequency. Larger studies will need to be performed to understand whether the use of multiple systems concurrently leads to improved clinical results in patients who are initially treatment resistant to neuromodulation. [ABSTRACT FROM AUTHOR]

Introduction: Youth account for a disproportionate number of new HIV infections; however, pre-exposure prophylaxis (PrEP) use is limited. We evaluated PrEP counselling rates among non-Hispanic Black youth in the United States after a bacterial sexually transmitted infection (STI) diagnosis. Methods: We conducted a retrospective cohort study of Black youth receiving care at two academically affiliated clinics in Philadelphia between June 2014 and June 2019. We compared PrEP counselling for youth who received primary care services versus those who did not receive primary care services, all of whom met PrEP eligibility criteria due to STI diagnosis per U.S. Centers for Disease Controland Prevention clinicalpractice guidelines. Two logistic regression models for receipt of PrEP counselling were fit: Model1 focused on sexualand gender minority (SGM) status and Model2 on rectalSTIs with both models adjusted for patient- and healthcare-level factors. Results: Four hundred and sixteen patients met PrEP eligibility criteria due to STI based on sex assigned at birth and sexual partners. Thirty patients (7%) had documentation of PrEP counselling. Receipt of primary care services was not significantly associated with receipt of PrEP counselling in either Model1 (adjusted OR (aOR) 0.10 [95% CI 0.01, 0.99]) or Model2 (aOR 0.52 [95% CI 0.10, 2.77]). Receipt of PrEP counselling was significantly associated with later calendar years of STI diagnosis (aOR 6.80 [95% CI 1.64, 29.3]), assigned male sex at birth (aOR 26.2 [95% CI 3.46, 198]) and SGM identity (aOR 317 [95% CI 39.9, 2521]) in Model1 and later calendar years of diagnosis (aOR 3.46 [95% CI 1.25, 9.58]), assigned male sex at birth (aOR 18.6 [95% CI 3.88, 89.3]) and rectal STI diagnosis (aOR 28.0 [95% CI 8.07, 97.5]) in Model2. Fourteen patients (3%) started PrEP during the observation period; 12/14 (86%) were SGM primary care patients assigned male sex at birth. Conclusions: PrEP counselling and uptake among U.S. non-Hispanic Black youth remain disproportionately low despite recent STI diagnosis. These findings support the need for robust investment in PrEP-inclusive sexualhealth services that are widely implemented and culturally tailored to Black youth, particularly cisgender heterosexualfemales. Keywords: pre-exposure prophylaxis; adolescents; sexually transmitted diseases; key and vulnerable populations; HIV prevention; gender, 1 | INTRODUCTION Human immunodeficiency virus (HIV) and sexually transmitted infections (STIs) among youth (individuals aged 13-24 years) are an enduring public health issue in the United States. In 2018, [...]