The effect of subcutaneously injected nicotine on achilles tendon healing in rabbits

The objective of this study was to evaluate the effect of subcutaneously injected nicotine on transversely transected and sutured achilles tendon healing in an experimental rabbit model. Adult New Zealand rabbits (n=22) weighting 3,000-3,500 g were used in this experimental study. Rabbits were randomly divided into two groups. Achilles tendon was transversely incised and repaired in all animals. In the experiment group subcutaneous injection of Nicotine tartrate 3 mg/kg/day was done. In the control group Serum physiologic injection was done at the same dosage. The injections were made three times a day in equal dosages. Nicotine and SF injections were made until the end of the 8-week, and then all animals were euthanized. Both light microscopic and electron microscopic evaluations were made on 14 animals. In N group light microscopic evaluation showed a visible gap in repair site. The total tendon score represented in N group was less than in SF group. The statistical analysis of the groups was significantly different for total tendon scores (P=0.002). Beside this electron microscopic examination showed inactive and degenerated fibroblasts and irregular collagen fibrils around them as well as collagen synthesis interruption in N group. Biomechanical evaluation was made on eight animals. The average tensile strength values in Group N (139.47 +/- 44.55 N) were significantly lower than those in Group SF (265.9 +/- 39.01 N) (z=2.309, P=0.029). Nicotine is the major chemical component common to all cigarettes and previously has been shown to affect wound and fracture healing adversely. The results of this study show that nicotine impairs achilles tendon healing after a surgical repair

Sub-bandgap optical absorption spectroscopy of hydrogenated microcrystalline silicon thin films prepared using hot-wire CVD (cat-CVD) process

Hydrogenated microcrystalline silicon (mu c-Si:H) thin films with different silane concentration (SC) have been prepared using the HWCVD technique. Dual beam photoconductivity (DBP), photothermal deflection spectroscopy (PDS), and transmission measurements have been used to investigate the optical properties of the mu c-Si:H films. Two different sub-bandgap absorption, alpha(hv), methods have been applied and analyzed to obtain a better insight into the electronic states involved. A good agreement has been obtained in the absorption spectrum obtained from the PDS and DBP measurements at energies above the bandgap. Differences between PDS and DBP spectra exist below the bandgap energy where DBP spectra always give lower alpha(hv) values and show a dependence on the SC. For some films, differences exist in the alpha(hv) spectra when the DBP measurements are carried out through the film and substrate side. In addition, for some films, there remains fringe pattern left on the spectrum after the calculation of the fringe-free absorption spectrum, which indicates structural inhomogeneities present throughout the film. (c) 2005 Elsevier B.V. All rights reserved

Characteristics of the study sample for the cross-sectional study part.

<p>Characteristics of the study sample for the cross-sectional study part.</p

Characteristics of the study sample for the longitudinal study part.

<p>Characteristics of the study sample for the longitudinal study part.</p

Trend of endorsement between 2010 and 2015.

<p>ICMJE = recommendations by the ICMJE; CoI = Conflict of interest. Within each curve the dots show the percentage of journals which endorsed the domains in 2010, 2012 and 2015 respectively (from left to right)</p

Characteristics of the study sample for the cross-sectional study part.

<p>Characteristics of the study sample for the cross-sectional study part.</p

Endorsement of domains in author instructions in 2015.

<p>Endorsement of domains in author instructions in 2015.</p

Association of journal characteristics with change in journal impact factor (2014–2010) for both the full model (Full) containing all covariates as well as the final model (Final) as a result of model selection.

<p>Association of journal characteristics with change in journal impact factor (2014–2010) for both the full model (Full) containing all covariates as well as the final model (Final) as a result of model selection.</p