Translational diffusion coefficient of cycloamylose in aqueous sodium hydroxide.

Biopolymers

Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.

Published: August 2003

Seven cyclic (1 --> 4)-alpha-D-glucan (cycloamylose) samples ranging in weight-average molecular weight from 5 x 10(3) to 1.8 x 10(4) and gamma-cyclodextrin have been studied by sedimentation equilibrium in dimethylsulfoxide (at 25 degrees C) and by dynamic light scattering in 0.5 N aqueous sodium hydroxide (at 25 degrees C), a good solvent for linear amylose. The measured translational diffusion coefficients D in the aqueous NaOH agree fairly closely with previous Monte Carlo results for cyclic (1 --> 4)-alpha-D-glucan chains with excluded volume, when correction is made for the effects of bead diameter and fluctuating hydrodynamic interaction (HI) on the Kirkwood theory on which the computation of D was based. These D data are also explained almost quantitatively by Yamakawa and Fujii's expression for the associated KP ring (based on the Kratky-Porod wormlike chain) with the molecular parameters for linear amylose if the fluctuating HI and excluded-volume effects are taken into account. It is concluded that the translational diffusion behavior of cycloamylose in the aqueous NaOH is consistent with the conformational characteristics derived from the conformational energy of maltose and dilute-solution data for linear amylose.

Download full-text PDF

Source
http://dx.doi.org/10.1002/bip.10393DOI Listing

Publication Analysis

Top Keywords

translational diffusion
12
linear amylose
12
cycloamylose aqueous
8
aqueous sodium
8
sodium hydroxide
8
cyclic -->
8
--> 4-alpha-d-glucan
8
aqueous naoh
8
diffusion coefficient
4
coefficient cycloamylose
4

Similar Publications

Lung tissue from human patients and murine models of sickle cell disease pulmonary hypertension (SCD-PH) show perivascular regions with excessive iron accumulation. The iron accumulation arises from chronic hemolysis and extravasation of hemoglobin (Hb) into the lung adventitial spaces, where it is linked to nitric oxide depletion, oxidative stress, inflammation, and tissue hypoxia, which collectively drive SCD-PH. Here, we tested the hypothesis that intrapulmonary delivery of hemopexin (Hpx) to the deep lung is effective at scavenging heme-iron and attenuating the progression of SCD-PH.

View Article and Find Full Text PDF

Congenital syphilis remains a significant global health concern, with severe morbidity and mortality if undiagnosed and untreated. Although many infants appear asymptomatic at birth, subtle clinical signs-including bullous lesions (congenital bullous syphilis, also known as pemphigus syphiliticus)-may facilitate early detection. Recognizing this rare manifestation is crucial for timely intervention, reducing serious outcomes.

View Article and Find Full Text PDF

Prostate cancer (PCa) is a high-prevalence disease usually characterized by metastatic spread to the pelvic lymph nodes and bones and the development of visceral metastases only in the late stages of disease. Positron Emission Tomography (PET) plays a key role in the detection of PCa metastases. Several PET radiotracers are used in PCa patients according to the stage and pathological features of the disease, in particular Ga/F-prostate-specific membrane antigen (PSMA) ligands.

View Article and Find Full Text PDF

Fewer than 10 % of children with diffuse midline glioma (DMG) survive 2 years from diagnosis. Radiation therapy remains the cornerstone of treatment and there are no medicinal products with regulatory approval. Although the biology of DMG is better characterized, this has not yet translated into effective treatments.

View Article and Find Full Text PDF

Background: Healthy individuals demonstrate considerable heterogeneity upon dynamic quantitative sensory testing assessment of endogenous pain modulatory mechanisms. For those who stratify into a 'pro-nociceptive profile' cohort, consisting of inefficient conditioned pain modulation (CPM) and elevated temporal summation of pain (TSP), the optimal approach for balancing the net output of pain modulatory processes towards anti-nociception remains unresolved. In this translational healthy human and rat study, we examined whether descending modulation countered spinal amplification during concurrent application of a CPM and TSP paradigm alongside pupillometry since pontine activity was previously linked to functionality of endogenous pain modulatory mechanisms and pupil dilation.

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!