While recent years have seen great progress in determining the three-dimensional structure of isolated proteins, monitoring protein structure inside live cells remains extremely difficult. Here, we examine the utility of Fourier transform infrared (FTIR) spectroscopy as a probe of protein structure in live bacterial cells. Selective isotope enrichment is used both to distinguish recombinantly expressed NuG2b protein from the cellular background and to examine the conformation of specific residues in the protein.
View Article and Find Full Text PDFVibrational-electronic (vibronic) coupling plays a critical role in excitation energy transfer in molecular aggregates and pigment-protein complexes (PPCs). But the interplay between excitonic delocalization and vibronic interactions is complex, often leaving even qualitative questions as to what conceptual framework (e.g.
View Article and Find Full Text PDFBackground: Pancreatic cystic lesions (PCLs) are followed for years due to older and likely biased works demonstrating a strong association with pancreatic carcinoma; more recent data are needed clarifying this relationship.
Purpose: To determine the association between PCLs on MRI and a synchronous or future diagnosis of pancreatic carcinoma.
Study Type: Single-center retrospective cohort.
Amide I spectroscopy probes the backbone C=O stretch vibrations of peptides and proteins. Amide I spectra are often collected in deuterated water (DO) since this provides a cleaner background in the amide I frequency range; such data are often referred to as amide I' spectra since deuteration induces changes in the mode structure, including a roughly ∼10 cm redshift. For biological samples, however, deuteration is often not possible.
View Article and Find Full Text PDFJ Allergy Clin Immunol Pract
February 2022
Chimeric antigen receptor (CAR) T-cell therapy is a dynamic therapy of engineered T cells targeting neoplastic cells, which offers impressive long-term remissions for aggressive relapsed/refractory hematologic malignancies. However, side effects including severe infections can be life-threatening. Multiple factors, including cytokine release syndrome, B-cell aplasia, and hypogammaglobulinemia, contribute to infection risk.
View Article and Find Full Text PDFPhotosynthetic pigment-protein complexes control local chlorophyll (Chl) transition frequencies through a variety of electrostatic and steric forces. Site-directed mutations can modify this local spectroscopic tuning, providing critical insight into native photosynthetic functions and offering the tantalizing prospect of creating rationally designed Chl proteins with customized optical properties. Unfortunately, at present, no proven methods exist for reliably predicting mutation-induced frequency shifts in advance, limiting the method's utility for quantitative applications.
View Article and Find Full Text PDFThe purpose of this study is to determine the impact of LI-RADS ancillary features on MRI and to ascertain whether the number of ancillary features can be reduced without compromising LI-RADS accuracy. A total of 222 liver observations in 81 consecutive patients were identified on MRI between August 2013 and December 2018. The presence or absence of major and ancillary features was used to determine the LI-RADS category for LR-1 to LR-5 observations.
View Article and Find Full Text PDFN-acylethanolamines (NAEs), which include the endocannabinoid anandamide, represent an important family of signaling lipids in the brain. The lack of chemical probes that modulate NAE biosynthesis in living systems hamper the understanding of the biological role of these lipids. Using a high-throughput screen, chemical proteomics and targeted lipidomics, we report here the discovery and characterization of LEI-401 as a CNS-active N-acylphosphatidylethanolamine phospholipase D (NAPE-PLD) inhibitor.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
April 2020
Preeclampsia is a serious hypertensive disorder of pregnancy, which is only cured with delivery of the placenta, thereby commonly necessitating preterm birth of the fetus. Low-molecular-weight heparin (LMWH) has demonstrated potential to reduce the incidence of preeclampsia in high-risk pregnant women, although the underlying mechanism by which LMWH protects against preeclampsia is unknown. Given the complex structure and biologic actions of heparin, we tested the hypothesis that heparin can mediate preeclampsia prevention via nonanticoagulant pathways.
View Article and Find Full Text PDFBackground: Specific-sized species of the carbohydrate hyaluronan elicit a variety of cellular responses mediating tissue integrity and repair, as well as regulating inflammatory responses. Orally provided hyaluronan with an average molecular weight of 35 kDa (HA35) protects mice from short-term ethanol (EtOH)-induced liver injury. This protection was associated with maintenance of the colocalization of zonula occludens-1 (ZO-1) and occludin at tight junctions in the proximal colon.
View Article and Find Full Text PDFJ Thromb Haemost
June 2018
Pre-eclampsia, a hypertensive disorder of pregnancy, continues to be a significant cause of global maternal morbidity. Low-dose aspirin remains the only standard-of-care prophylactic therapy for preventing pre-eclampsia, but is limited in efficacy. Heparin and its derivatives may further enhance the efficacy of aspirin therapy to prevent pre-eclampsia, but the mechanisms mediating this augmentative effect are not known.
View Article and Find Full Text PDFLow molecular weight heparin (LMWH) is being investigated as a potential preventative therapy against preeclampsia. There is evidence suggesting that LMWH may prevent preeclampsia through anticoagulation-independent mechanisms. In this study, we compared the in vitro placental, endothelial, and anti-inflammatory effects of an LMWH (dalteparin) with a nonanticoagulant, glycol-split heparin derivative (gsHep).
View Article and Find Full Text PDFThis article describes the basic technology and technique behind modified virtual colonoscopy (MVC). It is accompanied by images illustrating the possibility of MVC to advance the imaging for endometriosis beyond the current modalities of magnetic resonance imaging (MRI) and ultrasound. A quantification system is described that will ultimately make staging and multicenter prospective scientific studies possible for rectogenital and disseminated endometriosis.
View Article and Find Full Text PDFInt J Dev Biol
January 2015
Cardiovascular development is crucial to the survival of higher organisms, integrally transporting oxygen and nutrients and in later life, facilitating immune function. Only in recent years has the molecular basis of the formation of this ancient conduit system been explored. While transcription factors are essential to specify and differentiate core cellular and structural components of the developing heart and vessels, only a subset of these essential factors are currently known.
View Article and Find Full Text PDFPolyphosphate, synthesized by all cells, is a linear polymer of inorganic phosphate. When released into the circulation, it exerts prothrombotic and proinflammatory activities by modulating steps in the coagulation cascade. We examined the role of polyphosphate in regulating the evolutionarily related proteolytic cascade complement.
View Article and Find Full Text PDFFollicle-stimulating hormone (FSH) activates FSH receptors (FSHR) in granulosa cells to induce follicle differentiation, growth and estradiol production. FSH is used clinically to treat female infertility and is administered by injection. To increase patient convenience and compliance, compound homogeneity and composition, low molecular weight (LMW), orally bioavailable, FSHR agonists are now being developed to replace FSH.
View Article and Find Full Text PDFParathyroid hormone (PTH) is an anabolic agent that mediates bone formation through activation of the Gα(s)-, Gα(q)- and β-arrestin-coupled parathyroid hormone receptor type 1 (PTH1R). Pharmacological evidence based on the effect of PTH(7-34), a PTH derivative that is said to preferentially activate β-arrestin signaling through PTH1R, suggests that PTH1R-activated β-arrestin signaling mediates anabolic effects on bone. Here, we performed a thorough evaluation of PTH(7-34) signaling behaviour using quantitative assays for β-arrestin recruitment, Gα(s)- and Gα(q)-signaling.
View Article and Find Full Text PDFRecurrent microdeletions of 8p23.1 that include GATA4 and SOX7 confer a high risk of both congenital diaphragmatic hernia (CDH) and cardiac defects. Although GATA4-deficient mice have both CDH and cardiac defects, no humans with cardiac defects attributed to GATA4 mutations have been reported to have CDH.
View Article and Find Full Text PDFThis clinical opinion explores the current "zeitgeist" of minimally invasive gynaecological surgery (MIGS) as reflected in opinions expressed at the 40th AAGL conference held in Hollywood, Florida. It addresses concerns relating to the introduction of MIGS globally and the current position of robotic surgery in relation to conventional minimally invasive techniques like vaginal hysterectomy and minilaparotomy. It also explores challenges relating to MIGS in the healthcare environment of the 21st century.
View Article and Find Full Text PDF