Secondary structure estimation and properties analysis of stretched Asian and Caucasian hair.

BACKGROUND: In this previous work, we investigated the secondary structure changes of stretched yak hairs by deconvolution, secondary derivation, and curve fitting and determined the number of bands and their positions in order to resolve the protein spectrum of Raman spectroscopy. OBJECTIVES: The secondary structure estimation and properties analysis of stretched Asian and Caucasian hair were investigated by Fourier transform infrared spectroscopy, tensile curves, and measurement of density. METHODS: The hairs were stretched, dried, and baked at ratios 20%, 40%, 60%, 80% and 100%. RESULTS: The analysis of the amide I band indicated that the transformation from α-helix to ß-pleated structure occurred during the stretching process, which could be verified from the tensile analysis. The cysteine oxide in S-O vibration area exhibited that stretching led to the breakage of the disulfide bonds. When the stretching ratio of Caucasian hair was more than a certain ratio, the fiber macromolecular structure was destroyed because Caucasian hair had finer diameter and less medulla than Asian hair. The ß turn was easier to retract compared with other conformations, resulted in the content increase. The density measurements revealed that the structure of Caucasian hair was indeed more destroyed than that of Asian hair. The cuticles characterization indicated the length of scales was stretched longer and the thickness became thinner. Caucasian hair tended to collapse to form small fragments at the early stage of stretching. With the increase in stretching ratio, the scales of Caucasian hair lifted up, then flaked off and the scale interval increased accordingly. Asian hair was more easily peeled off than Caucasian hair cuticles with the increase in stretching ratio. CONCLUSIONS: The secondary structure of Caucasian hair was destroyed more easily than that of Asian hair.

Effectiveness of olfactory ensheathing cell transplantation for treatment of spinal cord injury.

The aim of this study was to determine the effectiveness and safety of transplantation of olfactory ensheathing cells for functional repair of the spinal cord. An olfactory bulb was obtained from a 4- to 5-month-old aborted fetus, and it was digested into single olfactory ensheathing cells and then cultured and purified for 1 to 2 weeks. Under general anesthesia, these single-cell suspensions of olfactory ensheathing cells were injected into the corresponding spinal injury site with 0.45-mm-diameter injections. The American Spinal Injury Association (ASIA) Impairment Scale was used to evaluate spinal function. A total of 15 patients (12 men, 3 women; age range, 18-56 years; mean age, 40) were admitted for obsolete spinal injuries. Spinal functions of the 15 patients were observed and followed postoperatively for a period ranging from 2 weeks to 1 month. All the 15 patients exhibited improvements in spinal function, and the improvement tendencies continued. Twelve patients had obvious spinal function improvement, and three had slight improvement according to the ASIA scale, with an obvious difference between preoperation and postoperation measures (P < 0.05). No fevers, infections, functional deteriorations, or deaths were seen. Thus, transplantation of olfactory ensheathing cells promoted spinal and neurofunctional recovery in patients with malignant spinal injuries, and this therapeutic method was safe.

An association study of 20 candidate genes with cryptorchidism in Siberian Husky dogs.

Cryptorchidism (CO) as a common developmental defect in purebred dogs causes health concerns of reduced fertility and increases risk of testicular malignancies. A total of 49 single nucleotide polymorphisms (SNPs) discovered from 20 candidate genes was investigated to analyse their associations with CO in Siberian Huskies. The sibling-transmission disequilibrium test on 38 discordant full-sibs revealed seven SNPs in the collagen type II alpha 1 (COL2A1) gene were significantly (p < 0.05) or suggestively (p < 0.10) associated with CO. Further analyses showed that only one SNP (rs23358342) in this gene remained suggestively significant (p < 0.1) on a data set of full-sibs with additional related dogs, but not significant on all 156 Siberian Huskies. Based on the statistical results and the involvement of COL2A1 in the testicle development and descent, we could not exclude COL2A1 as a potential candidate gene for CO in Siberian Huskies. Further studies are necessary to clarify these results from our relatively small sample size.

Stent of shape-memory alloy for urethral obstruction caused by benign prostatic hyperplasia.

Dilation and positioning a stent in the prostatic urethra have become important alternatives for the management of benign prostatic hyperplasia (BPH), but both have significant drawbacks, namely the need to repeat the treatment in the former case and the conflict between the introducing means and the generation of sufficient expansile force in the latter case. A spiral of a Chinese titanium-nickel alloy with shape memory was implanted in 25 patients with BPH using a self-made coaxial sheath. With a follow-up of 3 to 20 months, the success rate is 92%. There has been no encrustation or migration of the spirals. We deem the spiral of this shape-memory alloy to be a good alternative in patients with BPH who are unfit for surgery.