Distinct features of brain perivascular fibroblasts and mural cells revealed by in vivo two-photon imaging

Perivascular fibroblasts (PVFs) are recognized for their pro-fibrotic role in many central nervous system disorders. Like mural cells, PVFs surround blood vessels and express Pdgfrβ. However, these shared attributes hinder the ability to distinguish PVFs from mural cells. We used in vivo two-photon imaging and transgenic mice with PVF-targeting promoters (Col1a1 or Col1a2) to compare the structure and distribution of PVFs and mural cells in cerebral cortex of healthy, adult mice. We show that PVFs localize to all cortical penetrating arterioles and their offshoots (arteriole-capillary transition zone), as well as the main trunk of only larger ascending venules. However, the capillary zone is devoid of PVF coverage. PVFs display short-range mobility along the vessel wall and exhibit distinct structural features (flattened somata and thin ruffled processes) not seen with smooth muscle cells or pericytes. These findings clarify that PVFs and mural cells are distinct cell types coexisting in a similar perivascular niche.

Acute Postoperative Seizures and Engel Class Outcome at 1 Year Postselective Laser Amygdalohippocampal Ablation for Mesial Temporal Lobe Epilepsy

BACKGROUND

MRI-guided laser interstitial thermal therapy (MRgLITT) for mesial temporal lobe epilepsy is a safe, minimally invasive alternative to traditional surgical approaches. Prognostic factors associated with efficacy are debated; preoperative epilepsy duration and semiology seem to be important variables.

OBJECTIVE

To determine whether acute postoperative seizure (APOS) after MRgLITT for mesial temporal lobe epilepsy is associated with seizure freedom/Engel class outcome at 1 year.

METHODS

A single-institution retrospective study including adults undergoing first time MRgLITT for mesial temporal lobe epilepsy (2010-2019) with ≥1-year follow-up. Preoperative data included sex, epilepsy duration, number of antiepileptics attempted, weekly seizure frequency, seizure semiology, and radiographically verified anatomic lesion at seizure focus. Postoperative data included clinical detection of APOS within 7 days postoperatively, and immediate amygdala, hippocampal, entorhinal, and parahippocampal residual volumes determined using quantitative imaging postprocessing. Primary outcome was seizure freedom/Engel classification 1 year postoperatively.

RESULTS

Of 116 patients, 53% (n = 61) were female, with an average epilepsy duration of 21 (±14) years, average 6 failed antiepileptics (±3), and weekly seizure frequency of 5. APOS was associated with worse Engel class (P = .010), conferring 6.3 times greater odds of having no improvement vs achieving seizure freedom at 1 year. Residual amygdala, hippocampal, entorhinal, and parahippocampal volumes were not statistically significant prognostic factors.

CONCLUSION

APOS was associated with a lower chance of seizure freedom at 1 year post-MRgLITT for mesial temporal lobe epilepsy. Amygdala, hippocampal, entorhinal, and parahippocampal residual volumes after ablation were not significant prognostic factors.

Life History and Rearing of Anastatus orientalis (Hymenoptera: Eupelmidae), an Egg Parasitoid of the Spotted Lanternfly (Hemiptera: Fulgoridae)

To support efforts to manage and contain spotted lanternfly (SLF), Lycorma delicatula White (Hemiptera: Fulgoridae), research is being conducted to develop classical biological control methods. To date, two potential biocontrol agents from China have been identified: an egg parasitoid, Anastatus orientalis, and a nymphal parasitoid, Dryinus sinicus Olmi (Hymenoptera: Dryinidae). The research detailed here focuses on investigating the biology and rearing of A. orientalis to assess its potential efficacy in a biocontrol program and optimize its rearing. Female wasps lived significantly longer than male wasps (68 and 23 d, respectively) and females produced an average of 94 total progeny that successfully emerged as adults, with most progeny produced between weeks one and four of the females' lives. The sex ratio of the progeny, with no re-mating, was initially highly female-biased but became progressively more male-biased, likely due to sperm depletion. There was no evidence of additional mortality to SLF eggs from wasp host feeding, but the data were highly variable and the sample size was small. There was high parasitoid emergence when oviposition conditions mimicked mid-September Beijing temperature and photoperiod; however, there was little emergence under 25°C and long-day conditions because most progeny entered a diapause. Storage of parasitized eggs in 5°C chill lowered parasitoid emergence rates. Lastly, there was no evidence that storing field-collected SLF egg masses in 5°C for 10 mo prior to parasitization affected parasitism rates. These findings inform our rearing protocol for A. orientalis and facilitate our testing of this species as a potential biological control agent for SLF.

Stereotactic Brain Biopsy Hemorrhage Risk Factors and Implications for Postoperative Care at a Single Institution: An Argument For Postoperative Imaging

OBJECTIVE

To determine preoperative factors contributing to postoperative hemorrhage after stereotactic brain biopsy (STB), clinical implications of postoperative hemorrhage, and the role of postoperative imaging in clinical management.

METHODS

Retrospective review of STB (2005-2018) across 2 institutions including patients aged >18 years undergoing first STB. Patients with prior craniotomy, open biopsy, or prior STB were excluded. Preoperative variables included age, sex, neurosurgeon seniority, STB method. Postoperative variables included pathology, postoperative hemorrhage on computed tomography, immediate and 30-day postoperative seizure, infection, postoperative hospital stay duration, and 30-day return to operating room (OR). Analysis used the Fisher exact tests for categorical variables.

RESULTS

Overall, 410 patients were included. Average age was 56.5 (±16.5) years; 60% (n = 248) were men. The majority of biopsies were performed by senior neurosurgeons (66%, n = 270); frontal lobe (42%, n = 182) and glioblastoma (45%, n = 186) were the most common location and pathology. Postoperative hemorrhage occurred in 28% (114) of patients with 20% <0.05 cm³ and 8% >0.05 cm³. Postoperative hemorrhage of any size was associated with increased rate of postoperative deficit within both 24 hours and 30 days, postoperative seizure, and length of hospital stay when controlling for pathology. Hemorrhages >0.05 cm³ had a 16% higher rate of return to the OR for evacuation, due to clinical deterioration as opposed to radiographic progression.

CONCLUSIONS

Postbiopsy hemorrhage was associated with higher risk of immediate and delayed postoperative deficit and seizure. Postoperative computed tomography should be used to determine whether STB patients can be discharged same day or admitted for observation; clinical evaluation should determine return to OR for evacuation.