Spine growth precedes synapse formation in the adult neocortex in vivo

Dendritic spines appear and disappear in an experience-dependent manner. Although some new spines have been shown to contain synapses, little is known about the relationship between spine addition and synapse formation, the relative time course of these events, or whether they are coupled to de novo growth of axonal boutons. We imaged dendrites in barrel cortex of adult mice over 1 month, tracking gains and losses of spines. Using serial section electron microscopy, we analyzed the ultrastructure of spines and associated boutons. Spines reconstructed shortly after they appeared often lacked synapses, whereas spines that persisted for 4 d or more always had synapses. New spines had a large surface-to-volume ratio and preferentially contacted boutons with other synapses. In some instances, two new spines contacted the same axon. Our data show that spine growth precedes synapse formation and that new synapses form preferentially onto existing boutons.     

Microwave ablation for colorectal cancer metastasis to the liver: a single-center retrospective analysis

BackgroundThe purpose of this study is to evaluate the safety and intermediate-term efficacy of percutaneous microwave (MW) ablation for the treatment of colorectal liver metastases (CRLM) at a single institution.MethodsA retrospective review was performed of all CRLM treated with MW ablation from 3/2011 to 7/2020 (102 tumors; 72 procedures; 57 patients). Mean age was 60 years (range, 36–88) and mean tumor size was 1.8 cm (range, 0.5–5.0 cm). The patient population included 19 patients with extra-hepatic disease. Chemotherapy (pre- and/or post-ablation) was given in 98% of patients. Forty-five sessions were preceded by other focal CRLM treatments including resection, ablation, radiation, and radioembolization. Kaplan-Meier curves were used to estimate local tumor progression-free survival (LTPFS), disease-free survival (DFS), and overall survival (OS) and multivariate analysis (Cox Proportional Hazards model) was used to test predictors of OS.ResultsTechnical success (complete ablation) was 100% and median follow-up was 42 months (range, 1–112). There was a 4% major complication rate and an overall complication rate of 8%. Local tumor progression (LTP) rate during the entire study period was 4/98 (4%), in which 2 were retreated with MW ablation for a secondary LTP-rate of 2%. LTP-free survival at 1, 3, and 5 years was 93%, 58%, and 39% and median LTP-free survival was 48 months. OS at 1, 3, and 5 years was 96%, 66%, 47% and median OS was 52 months. There were no statistically significant predictors of OS.ConclusionsMW ablation of hepatic colorectal liver metastases appears safe with excellent local tumor control and prolonged survival compared to historical controls in selected patients. Further comparative studies with other local treatment strategies appear indicated.     

Mortality in the agricultural health study, 1993-2007

Comparing agricultural cohorts with the general population is challenging because the general healthiness of farmers may mask potential adverse health effects of farming. Using data from the Agricultural Health Study, a cohort of 89,656 pesticide applicators and their spouses (N = 89, 656) in North Carolina and Iowa, the authors computed standardized mortality ratios (SMRs) comparing deaths from time of the enrollment (1993-1997) through 2007 to state-specific rates. To compensate for the cohort's overall healthiness, relative SMRs were estimated by calculating the SMR for each cause relative to the SMR for all other causes. In 1,198,129 person-years of follow-up, 6,419 deaths were observed. The all-cause mortality rate was less than expected (SMR(applicators) = 0.54, 95% confidence interval (CI): 0.52, 0.55; SMR(spouses) = 0.52, 95% CI: 0.50, 0.55). SMRs for all cancers, heart disease, and diabetes were significantly below 1.0. In contrast, applicators experienced elevated numbers of machine-related deaths (SMR = 4.15, 95% CI: 3.18, 5.31), motor vehicle nontraffic accidents (SMR = 2.80, 95% CI: 1.81, 4.14), and collisions with objects (SMR = 2.12, 95% CI: 1.25, 3.34). In the relative SMR analysis for applicators, the relative mortality ratio was elevated for lymphohematopoietic cancers, melanoma, and digestive system, prostate, kidney, and brain cancers. Among spouses, relative SMRs exceeded 1.0 for lymphohematopoietic cancers and malignancies of the digestive system, brain, breast, and ovary. Unintentional fatal injuries remain an important risk for farmers; mortality ratios from several cancers were elevated relative to other causes.     

Roles for Event Representations in Sensorimotor Experience,Memory Formation,and Language Processing

The unifying theme for the papers in this volume is that event‐predictive representations play an important role in cognitive processes, and they are a particularly fruitful object of study for cognitive scientists. In this paper, we present our own model of event representations that draws together several disparate strands of research into event representations, relating to event perception, event encodings in working memory and their role in prediction, and events as they are reported in language. Our main claim is that the notion of deictic routines originally developed by Ballard et al. (1997) is of great use in explaining how these different types of event representation interface with one another.     

Twenty suicide assessment instruments: evaluation and recommendations

Twentyrelativelynew suicide assessment instruments can be grouped into the following categories: (a) clinician-rated suicide instruments, (b) self-rated suicide instruments, (c) self-rated buffers against suicide, (d) instruments focused on children and adolescents, and (e) special purpose scales. The present review describes these instruments, giving the potential clinician or researcher information about their psychometric properties, strengths, and weaknesses. They vary in length and the age group for which they are designed, but most are reliable and have some psychometric evidence of validity. Of the 20, most highlyrecommended are Beck's Scale for Suicide Ideation series, Linehan's Reasons for Living Inventory, and Cole's self-administered adaptation of Linehan's structured interview called the Suicidal Behaviors Questionnaire.