Volume exclusion in calcium selective channels.

Biophys J

Department of Molecular Biophysics and Physiology, Rush University Medical Center, Chicago, Illinois, USA.

Published: May 2008

Another research group has proposed an interesting model for calcium channel selectivity. However, on the basis of their reported results we find it impossible to assess the merits of their model because their results and claims concerning selectivity are based on an extrapolation over four orders of magnitude to low Ca(2+) concentration. Their results and claims have been presented in several articles and reviews in several journals and, thus, need attention. In this article, we first establish that we obtain results on electrostatics and channel occupancies similar to the high-concentration simulations they present. We then perform grand canonical ensemble simulations that enable us to study micromolar Ca(2+) concentrations. We find that their model channel is only weakly Ca(2+) selective. A crucial problem with their model appears to be the placement of the negatively charged glutamate structural elements in fixed positions inside the protein rather than as flexible units inside the filter.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2292364PMC
http://dx.doi.org/10.1529/biophysj.107.122796DOI Listing

Publication Analysis

Top Keywords

volume exclusion
4
exclusion calcium
4
calcium selective
4
selective channels
4
channels group
4
group proposed
4
proposed interesting
4
model
4
interesting model
4
model calcium
4

Similar Publications

Background: Hepatocellular carcinoma (HCC) associated with major vasculature tumor extension is considered an advanced stage of disease to which palliative radiotherapy or chemotherapy is proposed. Surgical resection associated with chemotherapy or chemoembolization could be an opportunity to improve overall survival and recurrence-free survival in selected cases in a high-volume hepatobiliary center. Moreover, it has been 25 years since Couinaud described the entity of a posterior liver located behind an axial plane crossing the portal bifurcation.

View Article and Find Full Text PDF

[Correlation between uterine volume and intrauterine adhesion: a propensity score matching analysis].

Zhonghua Fu Chan Ke Za Zhi

January 2025

Gynecological Minimally Invasive Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Health Care Hospital, Beijing 100006, China.

To investigate the correlation between uterine volume and intrauterine adhesion (IUA). From June 2018 to November 2019, totally 7 007 patients who underwent hysteroscopy in outpatient operating rooms of Gynecological Minimally Invasive Center, Beijing Obstetrics and Gynecology Hospital were retrospectively analyzed Patients of reproductive age with IUA without uterine fibroids and adenomyosis were selected as IUA group, and patients of reproductive age without uterine fibroids and adenomyosis without IUA during the same period were selected as the control group. The propensity score matching (PSM) method was used to perform 1∶1 matching for the two groups of patients, matching variables included age, height, weight, body mass index (BMI), gravidity, parity, and number of abortion curettage.

View Article and Find Full Text PDF

Growing evidence supports the importance of extracellular vesicle (EV) as mediators of communication in pathological processes, including those underlying respiratory disease. However, establishing methods for isolating and characterizing EVs remains challenging, particularly for respiratory samples. This study set out to address this challenge by comparing different EV isolation methods and evaluating their impacts on EV yield, markers of purity, and proteomic signatures, utilizing equine/horse bronchoalveolar lavage samples.

View Article and Find Full Text PDF

Objective: This study aimed to assess reachable workspace (RWS) in patients post-osteosynthesis of shoulder, elbow, or wrist fractures and explore correlations with self-reported function and kinesiophobia.

Design: An observational case-control study compared patients with fractures to a control group, utilizing questionnaires and 3D kinematic data.

Participants: The sample included 66 individuals who had undergone osteosynthesis: 21 with shoulder fractures, 10 with elbow fractures, and 22 with wrist fractures.

View Article and Find Full Text PDF

Background: Although randomized controlled trials (RCT) have demonstrated the efficacy of mepolizumab for asthma, they have excluded certain patient subgroups. To bridge the gap between RCT and real-world practice, the effectiveness of mepolizumab in a diverse population, including those potentially excluded from RCT, was assessed. Its effects on imaging findings and symptoms of chronic rhinosinusitis (CRS) with asthma were also assessed.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!