Insulin-producing β cells created from human pluripotent stem cells have potential as a therapy for insulin-dependent diabetes, but human pluripotent stem cell-derived islets (SC-islets) still differ ...from their in vivo counterparts. To better understand the state of cell types within SC-islets and identify lineage specification deficiencies, we used single-nucleus multi-omic sequencing to analyse chromatin accessibility and transcriptional profiles of SC-islets and primary human islets. Here we provide an analysis that enabled the derivation of gene lists and activity for identifying each SC-islet cell type compared with primary islets. Within SC-islets, we found that the difference between β cells and awry enterochromaffin-like cells is a gradient of cell states rather than a stark difference in identity. Furthermore, transplantation of SC-islets in vivo improved cellular identities overtime, while long-term in vitro culture did not. Collectively, our results highlight the importance of chromatin and transcriptional landscapes during islet cell specification and maturation.
All cells maintain ionic gradients across their plasma membranes, producing transmembrane potentials (V
). Mounting evidence suggests a relationship between resting V
and the physiology of ...non-excitable cells with implications in diverse areas, including cancer, cellular differentiation, and body patterning. A lack of non-invasive methods to record absolute V
limits our understanding of this fundamental signal. To address this need, we developed a fluorescence lifetime-based approach (VF-FLIM) to visualize and optically quantify V
with single-cell resolution in mammalian cell culture. Using VF-FLIM, we report V
distributions over thousands of cells, a 100-fold improvement relative to electrophysiological approaches. In human carcinoma cells, we visualize the voltage response to growth factor stimulation, stably recording a 10-15 mV hyperpolarization over minutes. Using pharmacological inhibitors, we identify the source of the hyperpolarization as the Ca
-activated K
channel K
3.1. The ability to optically quantify absolute V
with cellular resolution will allow a re-examination of its signaling roles.
Membrane potential (V
mem
) is a fundamental biophysical signal present in all cells. V
mem
signals range in time from milliseconds to days, and they span lengths from microns to centimeters. V
mem
...affects many cellular processes, ranging from neurotransmitter release to cell cycle control to tissue patterning. However, existing tools are not suitable for V
mem
quantification in many of these areas. In this review, we outline the diverse biology of V
mem
, drafting a wish list of features for a V
mem
sensing platform. We then use these guidelines to discuss electrode-based and optical platforms for interrogating V
mem
. On the one hand, electrode-based strategies exhibit excellent quantification but are most effective in short-term, cellular recordings. On the other hand, optical strategies provide easier access to diverse samples but generally only detect relative changes in V
mem
. By combining the respective strengths of these technologies, recent advances in optical quantification of absolute V
mem
enable new inquiries into V
mem
biology.
Biological membrane potentials, or voltages, are a central facet of cellular life. Optical methods to visualize cellular membrane voltages with fluorescent indicators are an attractive complement to ...traditional electrode-based approaches, since imaging methods can be high throughput, less invasive, and provide more spatial resolution than electrodes. Recently developed fluorescent indicators for voltage largely report changes in membrane voltage by monitoring voltage-dependent fluctuations in fluorescence intensity. However, it would be useful to be able to not only monitor changes but also measure values of membrane potentials. This study discloses a fluorescent indicator which can address both. We describe the synthesis of a sulfonated tetramethyl carborhodamine fluorophore. When this carborhodamine is conjugated with an electron-rich, methoxy (-OMe) containing phenylenevinylene molecular wire, the resulting molecule, CRhOMe, is a voltage-sensitive fluorophore with red/far-red fluorescence. Using CRhOMe, changes in cellular membrane potential can be read out using fluorescence intensity or lifetime. In fluorescence intensity mode, CRhOMe tracks fast-spiking neuronal action potentials (APs) with greater signal-to-noise than state-of-the-art BeRST 1 (another voltage-sensitive fluorophore). CRhOMe can also measure values of membrane potential. The fluorescence lifetime of CRhOMe follows a single exponential decay, substantially improving the quantification of membrane potential values using fluorescence lifetime imaging microscopy (FLIM). The combination of red-shifted excitation and emission, mono-exponential decay, and high voltage sensitivity enable fast FLIM recording of APs in cardiomyocytes. The ability to both monitor and measure membrane potentials with red light using CRhOMe makes it an important approach for studying biological voltages.
Cardiovascular disease is a common comorbidity and cause of mortality in chronic obstructive pulmonary disease. A better understanding of mechanisms of cardiovascular risk in chronic obstructive ...pulmonary disease patients is needed to improve clinical outcomes. We hypothesized that such patients have increased arterial stiffness, wave reflections, and subclinical atherosclerosis compared with controls and that these findings would be independent of smoking status and other confounding factors. A total of 458 patients with a diagnosis of chronic obstructive pulmonary disease and 1657 controls (43% were current or ex-smokers) with no airflow limitation were matched for age, sex, and body mass index. All individuals underwent assessments of carotid–femoral (aortic) pulse wave velocity, augmentation index, and carotid intima–media thickness. The mean age of the cohort was 67±8 years and 58% were men. Patients with chronic obstructive pulmonary disease had increased aortic pulse wave velocity (9.95±2.54 versus 9.27±2.41 m/s; P<0.001), augmentation index (28±10% versus 25±10%; P<0.001), and carotid intima–media thickness (0.83±0.19 versus 0.74±0.14 mm; P<0.001) compared with controls. Chronic obstructive pulmonary disease was associated with increased levels of each vascular biomarker independently of physiological confounders, smoking, and other cardiovascular risk factors. In this large case-controlled study, chronic obstructive pulmonary disease was associated with increased arterial stiffness, wave reflections, and subclinical atherosclerosis, independently of traditional cardiovascular risk factors. These findings suggest that the cardiovascular burden observed in this condition may be mediated through these mechanisms and supports the concept that chronic obstructive pulmonary disease is an independent risk factor for cardiovascular disease.Hypertension is published on behalf of the American Heart Association, Inc., by Wolters Kluwer Health, Inc. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution, and reproduction in any medium, provided that the original work is properly cited.
De Novo Oligometastatic Breast Cancer Pusztai, Lajos; Rozenblit, Mariya; Dubsky, Peter ...
Journal of clinical oncology,
12/2023, Letnik:
41, Številka:
34
Journal Article
Recenzirano
Odprti dostop
De novo oligometastatic breast cancer, a unique disease needing new treatment paradigms.
Serial DDs could serve as rapid check points to gauge the likelihood of success of continued resuscitation. Loudon et al.’s work combined with the use of serial DDs may serve as building blocks ...toward a trial using VETs to predict continued futile resuscitation.
Background
The objective of this study was to compare short-term outcomes of robotic and laparoscopic proctectomy in patients with inflammatory bowel disease (IBD).
Methods
This is an IRB-approved ...case-matched review. Seventeen robotic proctectomies (RP), 10 with ileal pouch anal anastomosis (IPAA) and 7 completion (CP), were matched to laparoscopic proctectomies (LP). Short-term and functional outcomes were compared between LP and RP.
Results
In CP cohort, operative times were longer in the RP group (351 RP vs 238 LP min,
p
= 0.03), mean robotic time 90 min. Estimated blood loss (EBL) was similar between RP-CP and LP-CP groups (
p
= 0.18). Return of bowel function (RBF) was slower in RP-CP group (3.0 vs 1.7 days,
p
= 0.04), and length of stay (LOS) was longer (6.4 vs 4.1 days,
p
= 0.02). In the IPAA group, there were no differences between operative times (
p
= 0.14), robotic time 86 min; EBL (
p
= 0.15), and postoperative complications. Return of bowel function (3.6 vs 2.6 days,
p
= 0.3) and LOS (8.5 vs 6.1 days,
p
= 0.17) were similar between RP and LP. Bowel and sexual function were equivalent between LP and RP-IPAA groups.
Conclusions
Robotic proctectomy is a safe and effective technique for patients with IBD. It is comparable to LP with regard to perioperative outcomes, complications, and short-term functional results.
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