The Distinctive Plant and Insect Assemblages of An Experimental Forest in Northern Lower Michigan (United States).

The effects of plants on insects are not completely clear due to potential covariation of weather or location affecting both assemblages. To address this question, plant and insect assemblages were described during summer 2019 and 2020 in two different forest habitats of northern Lower Michigan. The first habitat was a hardwood forest typical of secondary succession in the region. The second was a hydric forest located ~20 m from the hardwood forest which developed after lake sediment was deposited into a 10-ha area in the early 2000s. Reflecting this sediment deposition, soil of the hydric forest had higher water content and organic matter, and was dominated by the plant genera Solidago (Asterales: Asteraceae), Rubus (Rosales: Rosaceae), and Salix (Malpighiales: Salicaceae). In contrast, the hardwood forest had greater inorganic sediment and was dominated by Pteridium (Polypodiales: Dennstaedtiaceae), Carex (Poales: Cyperaceae), and Acer. Nearly 140,000 insect specimens were sampled using pitfall trapping, sweep netting, flight intercept trapping, ultraviolet light trapping, and yellow and blue pan trapping. The first three methods each sampled a unique insect assemblage, whereas the last three overlapped in taxa sampled. Insect assemblages of the two forests were distinct from each other using any of the six methods, with abundance of Pteridium and Salix (Sapindales: Sapindaceae) generally associating with changes in insect composition. A total of 41 insect taxa indicated the hydric forest and 14 indicated the hardwood forest. Insect richness increased with that of plants. These results demonstrate that differences in soil composition and plant assemblages associate with differences in forest insect assemblages, even of forests in very close proximity.

Paradoxical Association Between Relative Cerebral Blood Volume Dynamics Following Chemoradiation and Increased Progression-Free Survival in Newly Diagnosed IDH Wild-Type MGMT Promoter Methylated Glioblastoma With Measurable Disease.

Background and Purpose: While relative cerebral blood volume (rCBV) may be diagnostic and prognostic for survival in glioblastoma (GBM), changes in rCBV during chemoradiation in the subset of newly diagnosed GBM with subtotal resection and the impact of MGMT promoter methylation status on survival have not been explored. This study aimed to investigate the association between rCBV response, MGMT methylation status, and progression-free (PFS) and overall survival (OS) in newly diagnosed GBM with measurable enhancing lesions. Methods: 1,153 newly diagnosed IDH wild-type GBM patients were screened and 53 patients (4.6%) had measurable post-surgical tumor (>1mL). rCBV was measured before and after patients underwent chemoradiation. Patients with a decrease in rCBV >10% were considered rCBV Responders, while patients with an increase or a decrease in rCBV <10% were considered rCBV Non-Responders. The association between change in enhancing tumor volume, change in rCBV, MGMT promotor methylation status, and PFS or OS were explored. Results: A decrease in tumor volume following chemoradiation trended towards longer OS (p=0.12; median OS=26.8 vs. 16.3 months). Paradoxically, rCBV Non-Responders had a significantly improved PFS compared to Responders (p=0.047; median PFS=9.6 vs. 7.2 months). MGMT methylated rCBV Non-Responders exhibited a significantly longer PFS compared to MGMT unmethylated rCBV Non-Responders (p<0.001; median PFS=0.5 vs. 7.1 months), and MGMT methylated rCBV Non-Responders trended towards longer PFS compared to methylated rCBV Responders (p=0.089; median PFS=20.5 vs. 13.8 months). Conclusions: This preliminary report demonstrates that in newly diagnosed IDH wild-type GBM with measurable enhancing disease after surgery (5% of patients), an enigmatic non-response in rCBV was associated with longer PFS, particularly in MGMT methylated patients.