Molecular dynamics simulations of epidermal growth factor and transforming growth factor-alpha structures in water

AMBER v. 4.1 force field in 1.5 ns NPT molecular dynamics simulations of murine epidermal growth factor (mEGF), human epidermal growth factor (hEGF), and human transforming growth factor-alpha (hTGF-alpha) structures with explicit TIP3P solvation were used to investigate differences in backbone stability, changes in secondary structure, interdomain flexibility, and weakly polar interactions. Backbone root mean square deviations of sections of each peptide show that the most stable regions in mEGF and hEGF are the A-, B-, and C-loops, whereas the most stable regions in hTGF-alpha are the A- and B-loops. The secondary structure in the B-loops of mEGF and hEGF differ significantly from the nuclear magnetic resonance (NMR) structures of mEGF and hEGF. The position and type of turns in the B-loop of mEGF and hEGF increase the interstrand distance of the antiparallel beta-sheets thereby disrupting their structure. The interdomain flexibility of simulated hTGF-alpha structure is greater than in either mEGF or hEGF. The phi, psi dihedrals of hTGF-alpha occupy two distinct populations of phase space corresponding to either a Ceq7 or an alpha-helical conformation. This change in dihedral angle is stabilized by Phe15 with Arg42 and Phe17 with Arg42 N-pi weakly polar interactions that are present only in hTGF-alpha but not in mEGF or hEGF.     

Ultrasonography in children of cystic abdominal masses not related to the genitourinary system

A variety of cystic abdominal masses not related to the genitourinary tract may be encountered in the pediatric population. Ultrasound is the most informative imaging modality in the workup of these masses which include lymphangiomas, duplication cysts, enteric cysts, mesothelial cysts, pseudocysts, choledochal cysts, and gastrointestinal teratomas. The clinical and sonographic characteristics of these lesions are presented.     

Diagnostic importance of electrophysiologic tests in Bell's palsy: report on a longterm follow-up study in 100 cases (author's transl)

The present study is based upon the results of repeated electrodiagnostic tests carried out in a series of 100 cases of Bell's palsy (Determination of Rheobase and Chronaxy). The first symptoms of denervation can be observed during the second week after the onset of the paralysis. This seems to be the critical period in which the ultimate consequences of the lesion are determined: partial or total recovery or complete irreversible denervation. In cases showing a rapid increase of chronaxy during the 2nd week, prognosis is rather poor because a difference of 240% between the affected and the normal side indicates a progressive denervation. Cases in which the difference of chronaxy values during the 2nd week is increased upto 240% (i.e. partial denervation) recover incompletely in 15% of the cases. Estimation of prognosis in Bell's palsy and timing of a facial nerve decompression must be based on reliable facts, such as the results of repeated electrodiagnostic tests (modified measurement of Rheobase and Chronaxy) carried out at least every secont but preferably every day during the first 3 weeks after the onset of the paresis.     

Fine structure of the tapetum lucidum of the paca Cuniculus paca

The tapetum lucidum of the paca or spotted cavy (Cuniculus paca) has been studied by light and electron microscopy. The reflective layer in this species is a tapetum cellulosum situated in the choroid of the superior fundus. Posteriorly, the tapetum is composed of several layers of ovoid to flattened cells while peripherally the tapetum gradually thins down and disappears. Within the tapetal cells most cell organelles are located near the nucleus. The dominant feature of these cells is, however, a large accumulation of electron-dense rodlets which show a variety of sizes, shapes and orientations. These rodlets are the reflective material of the tapetum, and energy dispersive studies indicate that they are rich in sulphur. The diameter and spacing of these irregular rodlets is too varied to be consistent with the principles of constructive interference, and the tapetum in the paca is probably capable of only diffuse reflectance. The retinal epithelium over the tapetum is nonpigmented while in non-tapetal locations it is normally pigmented.     

Prayer as a coping strategy for chronic pain patients.

Prayer as a coping mechanism was examined in a group of 105 persons (average age 45 yrs) experiencing chronic pain for an average of 4.3 yrs. Previous research suggested that prayer may actually be associated with increased disability among individuals who develop a permanent, painful condition of 6 mo duration or longer. Assessment instruments included the Medical Coping Modes Questionnaire and 2 subscales of the West Haven-Yale Multidimensional Pain Inventory; prayer was measured by the Diverting Attention/Praying-Hoping Subscale of the Coping Strategies Questionnaire. Consistent with previous research, individuals who endorsed a greater use of prayer to cope with their pain also reported a greater degree of disability. Follow-up statistical analyses suggested that prayer was associated with avoidance suggestive of a passive coping response. Additional research is needed to clarify the relationship of prayer to avoidance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)