Exocytosis at synapses generally refers to fusion between vesicles and the plasma membrane
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. Although compound fusion between vesicles
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,
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was proposed at ribbon-type synapses
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,
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, whether it ...exists, how it is mediated, and what role it plays at conventional synapses remain unclear. Here we addressed this issue at a nerve terminal containing conventional active zones. High potassium application and high frequency firing induced giant capacitance up-steps reflecting exocytosis of vesicles larger than regular ones, followed by giant down-steps reflecting bulk endocytosis. They also induced giant vesicle-like structures, as observed with electron microscopy, and giant miniature EPSCs (mEPSCs) reflecting more transmitter release. Calcium and its sensor for vesicle fusion, synaptotagmin, were required for these giant events. After high frequency firing, calcium/synaptotagmin-dependent mEPSC size increase was paralleled by calcium/synaptotagmin-dependent post-tetanic potentiation (PTP). These results suggest that calcium/synaptotagmin mediates compound fusion between vesicles, that exocytosis of compound vesicles increases quantal size which enhances synaptic strength and thus contributes to the generation of PTP, and that exocytosed compound vesicles may be retrieved via bulk endocytosis. We suggest to include a new vesicle cycling route, compound exocytosis followed by bulk endocytosis, into models of synapses, where currently only vesicle fusion with the plasma membrane is considered (
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)
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Although endocytosis maintains synaptic transmission, how endocytosis is initiated is unclear. We found that calcium influx initiated all forms of endocytosis at a single nerve terminal in rodents, ...including clathrin-dependent slow endocytosis, bulk endocytosis, rapid endocytosis and endocytosis overshoot (excess endocytosis), with each being evoked with a correspondingly higher calcium threshold. As calcium influx increased, endocytosis gradually switched from very slow endocytosis to slow endocytosis to bulk endocytosis to rapid endocytosis and to endocytosis overshoot. The calcium-induced endocytosis rate increase was a result of the speeding up of membrane invagination and fission. Pharmacological experiments suggested that the calcium sensor mediating these forms of endocytosis is calmodulin. In addition to its role in recycling vesicles, calcium/calmodulin-initiated endocytosis facilitated vesicle mobilization to the readily releasable pool, probably by clearing fused vesicle membrane at release sites. Our findings provide a unifying mechanism for the initiation of various forms of endocytosis that are critical in maintaining exocytosis.
Reduced-dose nivolumab in combination with standard-dose ipilimumab improves objective response and progression-free survival compared with standard-dose ipilimumab alone, but increases toxicity. We ...assessed the safety and anti-tumour activity of standard-dose pembrolizumab in combination with reduced-dose ipilimumab.
In this open-label, phase 1b trial, we recruited patients from 12 medical centres in Australia, New Zealand, and the USA. Eligible patients were aged at least 18 years, had advanced melanoma, had an Eastern Coooperative Oncology Group performance status of 0 or 1, had measurable disease according to the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, had adequate organ function, had resolution of toxic effects of the most recent previous chemotherapy to grade 1 or less, had no active autoimmune disease requiring systemic steroids or immunosuppressive agents, had no active non-infectious pneumonitis, had no uncontrolled thyroid dysfunction or diabetes, had no active brain metastases, and had not received previous immune checkpoint inhibitor therapy. Patients received intravenous pembrolizumab 2 mg/kg plus intravenous ipilimumab 1 mg/kg every 3 weeks for four doses, followed by intravenous pembrolizumab 2 mg/kg every 3 weeks for up to 2 years or disease progression, intolerable toxicity, withdrawal of consent, or investigator decision. The primary endpoint was safety and tolerability. The proportion of patients achieving an objective response assessed per RECIST version 1.1 by independent central review and overall survival were secondary endpoints. We also assessed progression-free survival. The primary endpoint was assessed in all patients who received at least one dose of combination therapy. Activity was assessed in all enrolled patients. This trial is registered with ClinicalTrials.gov, number NCT02089685. Enrolment into this cohort is closed, but patients are still being monitored for safety and anti-tumour activity.
Between Jan 13, 2015, and Sept 17, 2015, we enrolled and treated 153 patients. As of the Oct 17, 2016, cutoff date, median follow-up was 17·0 months (IQR 14·8–18·8). 110 (72%) of 153 patients received all four pembrolizumab plus ipilimumab doses; 64 (42%) remained on pembrolizumab monotherapy. 110 grade 3–4 treatment-related adverse events occurred in 69 (45%) patients. No treatment-related deaths occurred. Treatment-related adverse events led to discontinuation of pembrolizumab and ipilimumab in 22 (14%) patients, including 17 (11%) who discontinued both treatments for the same event and five (3%) who discontinued ipilimumab for one event and later discontinued pembrolizumab for another. 12 (8%) patients discontinued ipilimumab only and 14 (9%) discontinued pembrolizumab only because of treatment-related adverse events. 158 immune-mediated adverse events of any grade occurred in 92 (60%) patients, and 50 immune-mediated adverse events of grade 3–4 occurred in 42 (27%) patients; the most common immune-mediated adverse events were hypothyroidism (25 16%) and hyperthyroidism (17 11%). 93 (61% 95% CI 53–69) patients achieved an objective response. Estimated 1 year progression-free survival was 69% (95% CI 60–75), and estimated 1 year overall survival was 89% (95% CI 83–93).
Standard-dose pembrolizumab given in combination with four doses of reduced-dose ipilimumab followed by standard-dose pembrolizumab has a manageable toxicity profile and provides robust anti-tumour activity in patients with advanced melanoma. These data suggest that standard-dose pembrolizumab plus reduced-dose ipilimumab might be a tolerable, efficacious treatment option for patients with advanced melanoma. A randomised phase 2 trial of alternative dosing strategies of this combination is underway.
Merck & Co, Inc.
Abstract
Motivation
Multiple biological clocks govern a healthy pregnancy. These biological mechanisms produce immunologic, metabolomic, proteomic, genomic and microbiomic adaptations during the ...course of pregnancy. Modeling the chronology of these adaptations during full-term pregnancy provides the frameworks for future studies examining deviations implicated in pregnancy-related pathologies including preterm birth and preeclampsia.
Results
We performed a multiomics analysis of 51 samples from 17 pregnant women, delivering at term. The datasets included measurements from the immunome, transcriptome, microbiome, proteome and metabolome of samples obtained simultaneously from the same patients. Multivariate predictive modeling using the Elastic Net (EN) algorithm was used to measure the ability of each dataset to predict gestational age. Using stacked generalization, these datasets were combined into a single model. This model not only significantly increased predictive power by combining all datasets, but also revealed novel interactions between different biological modalities. Future work includes expansion of the cohort to preterm-enriched populations and in vivo analysis of immune-modulating interventions based on the mechanisms identified.
Availability and implementation
Datasets and scripts for reproduction of results are available through: https://nalab.stanford.edu/multiomics-pregnancy/.
Supplementary information
Supplementary data are available at Bioinformatics online.
Measurement-based care (MBC), or the regular use of progress measures to inform clinical decision-making, improves quality of care and clinical outcomes. MBC typically focuses on standardized rather ...than individualized outcome measurement. In this pilot study, we examined the clinical utility of integrating individualized measurement with existing standardized outcome monitoring in a children's partial hospitalization program. Participants were 48 youth (M age 10.13 ± 1.39; 54.2% male, 41.7% female, 4.2% transgender or nonbinary). Comorbidity was common; 83.4% of youth had more than one diagnosis at intake. Using the Youth Top Problems for individualized outcome measurement, we examined Top Problem content and clinical improvement over time. Finally, we examined completion rates and describe implementation issues. Top Problems were heterogeneous and sensitive to change. Of the 144 problems, 107 (74%) had a focus consistent with measures used in program, while 37 (26%) were not captured by standardized measures used in program. Effect sizes from admission to final measurement ranged from Cohen's d = .75 - 1.00. Initial adoption of the MBC was strong, but sustained use of the system over the treatment course was challenging. Individualized outcome measurement in children's partial hospitalization programs is feasible to administer and sensitive to clinical change that is unique from change captured in standardized measures. Parents were able to self-identify clinically meaningful, highly individualized Top Problems. Challenges of implementation and clinical assessment in acute settings and potential strategies for improving implementation are discussed.
Objective The objective of the study was to determine total hospital costs and net hospital income for different types of minimally invasive hysterectomy and financial impact if a subset of patients ...underwent total vaginal hysterectomy (TVH) instead of their selected procedure. Study Design A retrospective chart review was performed of patients who underwent hysterectomy for benign disease by TVH, laparoscopic assisted vaginal hysterectomy (LAVH), total laparoscopic hysterectomy (TLH), and robotic hysterectomy (RH) between Jan. 1, 2007, and April 30, 2010, at Thomas Jefferson University Hospital. The hospital decision support database was used to calculate net hospital income. A subset of patients with at least 1 prior vaginal delivery, no more than 1 laparotomy, and a uterine size less than 14 weeks who had undergone RH, TLH, or LAVH was identified as potential TVH candidates. The financial impact of performing TVH over the selected hysterectomy was calculated. Results Three hundred thirty-four cases of minimally invasive hysterectomy were identified. Fifty-five percent were TVH, 33% LAVH, 3% TLH, and 9% RH. Mean total hospital costs for TVH were $7903, $10,069 for LAVH, $11,558 for TLH, and $13,429 for RH ( P < .0001). Net hospital income was $1260 for TVH. The hospital incurred losses of $–1306 for LAVH, $–4049 for TLH, and $–4564 for RH ( P = .03). Our criteria to determine the mode of hysterectomy increased TVH from 57% to 76% of all minimally invasive hysterectomy. Conclusion Hospital costs were greater with LAVH, TLH, and RH than for TVH. The hospital incurred financial losses with LAVH, TLH, and RH. TVH was the only minimally invasive modality of hysterectomy that generated net hospital income. Our conservative criteria to determine the route of hysterectomy would increase the number of TVHs by more than 30%.
Analyses of data from genome-wide association studies on unrelated individuals have shown that, for human traits and diseases, approximately one-third to two-thirds of heritability is captured by ...common SNPs. However, it is not known whether the remaining heritability is due to the imperfect tagging of causal variants by common SNPs, in particular whether the causal variants are rare, or whether it is overestimated due to bias in inference from pedigree data. Here we estimated heritability for height and body mass index (BMI) from whole-genome sequence data on 25,465 unrelated individuals of European ancestry. The estimated heritability was 0.68 (standard error 0.10) for height and 0.30 (standard error 0.10) for body mass index. Low minor allele frequency variants in low linkage disequilibrium (LD) with neighboring variants were enriched for heritability, to a greater extent for protein-altering variants, consistent with negative selection. Our results imply that rare variants, in particular those in regions of low linkage disequilibrium, are a major source of the still missing heritability of complex traits and disease.
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