[Experimental study on injury of the rat nasal mucosa by distilled water irrigation, and its regeneration]

Intrauterine infusion of povidone-iodine: Its effect on the endometrium and subsequent fertility in postpartum dairy cows

This study aimed to describe the duration of inflammation after intrauterine infusion of polyvinylpyrrolidone-iodine (povidone-iodine, PVP-I), determine the effect of PVP-I infusion on the subsequent fertility, and evaluate the histopathology of the endometrium in dairy cows. In Experiment 1, 120 lactating clinically healthy Holstein-Friesian cows at 5 weeks postpartum (W5) were equally divided into three groups: intrauterine infusion of 2% PVP-I (PVP), saline (SAL), and no treatment (NTX). Endometrial cytology was performed daily from D0 (W5) to D7 to determine the percentage of polymorphonuclear cells (PMN%) in 44 of the 120 cows. All cows received timed artificial insemination at D17. In Experiment 2, 25 cows were randomly classified into sacrifice at 24 hr or 48 hr after 2% PVP-I infusion (PVP24 and PVP48), and 24, 48, 72, or 96 hr after SAL infusion (SAL24; SAL48; SAL72; SAL96), or no treatment (NTX). Histopathology was performed on the uterus of each cow. In Experiment 1, PMN% was greater in PVP (P<0.05) than in SAL and NTX, on D1, but decreased to a level similar to that of the other groups by D2. Conception rate was higher (P<0.05) in PVP cows compared to SAL and NTX cows. In Experiment 2, stratified columnar epithelium in the uterus disappeared in PVP24 and SAL24. The epithelium was regenerated in PVP48, SAL72, and SAL96, but not in SAL48. In conclusion, the results of the study suggest that PVP-I induces transient uterine inflammation, promotes regeneration of endometrial epithelial cells and improves fertility.

Consensus on Methodology for Experimental Studies of Nasal Mucosal Injury

OBJECTIVES

The way wounds heal involves significant complexity, resulting in restoration of functional and anatomical integrity to tissues damaged as a result of trauma (whether mechanical, chemical, or radiation-induced). The authors reviewed the consensus on methodology for experimental studies of nasal mucosal injury.

METHODS

The review aims to find where consensus exists amongst different experimental studies in nasal wound healing about the use of animal models. To achieve this, the authors queried the Pubmed, Proquest Central and Google databases for the last 20 years (i.e. 1996-2016). The search terms were: "mucosa injury," "nasal mucosa injury," "injury," "wound healing," "nasal," "nasal wound healing," "experimental," "animal," "model," "rat," "rabbit," "guinea pig," and "mice." These terms were searched for whether they occurred singly or in combination. The search uncovered 18 papers, on the basis of which this review has been prepared.

RESULTS

The choice of an appropriate animal model is key in investigating nasal mucosal injury. Suitable animals include rodents such as rats or guinea pigs. There are reports in the literature concerning mechanical injury in rat nasal mucosae without attempts to treat it. Mechanical injury was induced unilaterally by means of an interdental brush. Other techniques involved the use of distilled water or irradiating the tissue to induce trauma.

CONCLUSION

In this review, the use of a rat, guinea pig or rabbit model for human nasal mucosal injury is reviewed. Such models are suitable for use in well-designed experimental studies.

Wound Healing of the Nasal and Paranasal Mucosa: A Review

Background

Wound healing is a highly coordinated process involving clot formation, inflammatory reaction, immune response, and, finally, tissue remodeling and maturation. Only few data regarding the specific healing of the nasal or sinusal mucosa are available.

Methods

After a short summary of the general principles of wound healing, the most important data regarding in vitro or in vivo models of wound healing of the nasal and paranasal mucosa are discussed. Attention is paid to clinical application.

Main Findings

First observations regarding the specific regulation of epithelial regeneration by growth factors have underlined the complex relationship between extracellular matrix and epithelium during the repair process. However, only poor and aspecific correlations can be described between endoscopically and histomorphologically defined postoperative phases.