Longer charged amino acids favor β-strand formation in hairpin peptides.

Interactions between charged amino acids significantly influence the structure and function of proteins. The encoded charged amino acids Asp, Glu, Arg, and Lys have different number of hydrophobic methylenes linking the backbone to the charged functionality. It remains to be fully understood how does this difference in the number of methylenes affect protein structure stability.

Insertion of Pro-Hyp-Gly provides 2 kcal mol stability but attenuates the specific assembly of ABC heterotrimeric collagen triple helices.

Collagen is a major structural component of the extracellular matrix and connective tissue. The key structural feature of collagen is the collagen triple helix, with a Xaa-Yaa-Gly (glycine) repeating pattern. The most frequently occurring triplet is Pro (proline)-Hyp (hydroxyproline)-Gly.

Efficacy of the WINROP algorithm for retinopathy of prematurity screening in Southern China.

Aim: To evaluate the predicting efficacy of severe retinopathy of prematurity (ROP) by the WINROP algorithm (http://winrop.com) in Southern China.

Methods: All preterm infants with the gestational age (GA) less than 32wk were included.

Antifouling and antibacterial behavior of membranes containing quaternary ammonium and zwitterionic polymers.

To overcome the organic-/bio- fouling of the membrane, a dual-functional ultrafiltration membrane containing quaternary ammonium and zwitterionic polymers via quaternization and surface radical polymerization was designed, and its antifouling and antibacterial behavior was studied. In this work, poly(vinylidene fluoride)/poly(methyl methacrylate-co-dimethylamino-2-ethyl methacrylate) (PVDF/P(MMA-co-DMAEMA)) blend membrane was quaternized by p-chloromethyl styrene (p-CMS), and the double bonds were introduced onto the membrane surface, which further participated in the polymerization of zwitterionic monomers on the membrane surface. The results indicated that the resultant membrane exhibited obviously improved hydrophilicity and weak positive charge (isoelectric point, 7.

New learning and memory related pathways among the hippocampus, the amygdala and the ventromedial region of the striatum in rats.

Background: The hippocampus, central amygdaloid nucleus and the ventromedial region (marginal division) of the striatum have been reported to be involved in the mechanism of learning and memory. This study aimed elucidating anatomical and functional connections among these brain areas during learning and memory.

Results: In the first part of this study, the c-Fos protein was used to explore functional connections among these structures.

The marginal division of the striatum and hippocampus has different role and mechanism in learning and memory.

The memory function of the hippocampal formation (Hip) and the marginal division (MrD) of neostriatum was compared. Rats with bilateral lesions of the MrD either immediate or 24 h after training in Y-maze were found to have decrease in correct runs in both groups. However, animals with transected afferent and efferent nerve bundles to isolate the Hip immediately or 24 h after training in Y-maze were found to show a decrease in correct runs only in the group injured immediately after Y-maze training but not in the 24 h group suggesting that MrD is likely involved in the entire process of long-term memory consolidation whereas the Hip only contributes to memory in the early stage.

Comparison of microRNA expression in hippocampus and the marginal division (MrD) of the neostriatum in rats.

Background: MicroRNAs (miRNAs), a class of highly conserved small non-coding RNA molecules, are known to play essential roles in central nervous system (CNS) by causing post-transcriptional gene silencing. There is much evidence that miRNAs have specific temporal and spatial expression patterns in the mammal brain, but little is known about the role of the region specificity for the gene regulatory networks of the brain. This study represents the first attempt to perform a profiling analysis of the differential expression of miRNAs between hippocampus and the Marginal division (MrD) of the neostriatum in the rat brain.

[Effects of intrathecal escin and clonidine in the treatment of neuropathic pain in rats].

Objective: To investigate the effects of intrathecal escin and clonidine, used alone or in combination, in the treatment of neuropathic pain in rats and the possible mechanism.

Methods: Ninety-six male SD rats weighing 250-300 g were chronically implanted with lumbar intrathecal catheters. One week later, the left L5 and L6 spinal nerve roots were ligated to establish the model of spinal nerve ligation neuropathic pain (SNL).

[Comparison of target controlled propofol infusion and sevoflurane inhalational anesthesia in laparoscopic cholecystectomy].

Objective: To compare the effects of propofol target controlled infusion (TCI) and sevoflurane inhalational anesthesia on the hemodynamics and postoperative recovery in patients undergoing laparoscopic cholecystectomy.

Methods: Sixty ASA IorII patients scheduled for laparoscopic cholecystectomy were randomized into propofol TCI group (group P) and sevoflurane inhalational anesthesia group (group S). In group P, TCI propofol was maintained after intubation until incision closure with the target concentration at 3 microg/ml.

[Acute normovolemic hemodilution combined with controlled hypotension in patients undergoing liver tumorectomy].

Objective: To evaluate the effects of acute normovolemic hemodilution (ANH) combined with controlled hypotension on reducing heterogeneous transfusion and safety during liver tumorectomy.

Methods: Thirty patients undergoing elective liver tumorectomy were randomly divided into 3 groups (10 each), namely ANH group (group A), ANH combined with controlled hypotension group (group B) and control group (group C). All the patients were anesthetized via endotracheal intubation.