Wistar rat dermis recellularization.

Skin lesions are normal to all species, regardless of gender or age. The skin, the largest organ of the body, has function as a primary barrier to the chemical, physical and biological aggressions of the environment. In animals, these lesions may be due to fights and/or predations, also as in humans, there is a very common cause of dermal lesions that are caused by burns and carcinomas. Looking for new techniques of tissue bioengineering, studies have been shown promising results for formulations of acellular biological scaffolds from tissue decellularization for the reconstitution of these lesions. The decellularization has its proof by a varied range of tests such as scanning electron microscopy and residual genomic DNA tests. Subsequently the tissue can go through the process of recellularization using cells of interest, even the animal that will receive this tissue, reducing the risks of rejection and improving the response to tissue transplantation. Thus, this manuscript aimed at the decellularization of the tissue with the use of chemical and physical means followed by sterilization and the establishment of a protocol for the recellularization of a decellularized scaffold from the Wistar rat dermis using murine fibroblasts and mesenchymal stem cells from canine adipose tissue for 7 days. After efficacy tests, the tissue recellularization were confirmed by immunofluorescence assays and scanning electron microscopy where the adherence of the cells in the biological scaffold was observed.

Reproductive system development in male and female horse embryos and fetuses: Gonadal hyperplasia revisited.

In horses, pregnancy is characterized by high levels of maternal estrogens that are produced largely by the interstitial tissue inside the gonads of the offspring, associated with a physiological gonadal hyperplasia, that is uncommon in other species. However, a detailed structural-functional understanding of the early stages of gonadal development and hyperplasia has remained elusive in horse pregnancy because of the lack of substantial data. The goal of this study was to describe the genital organs' development in 19 early horse embryos and fetuses (days 20-140 of gestation) of both sexes by means of anatomy, histology, stereology, and immunohistochemistry, with a specific focus on gonadal hyperplasia and interstitial tissue development. Gonadal hyperplasia with similar amounts of interstitial cells was observed in both sexes, but only during the early stage of development (days 40-90). Surprisingly, a higher degree of hyperplasia, characterized by larger amounts of interstitial cell-rich areas, was seen in fetal ovaries from 90 days of gestation onwards. Another novel aspect was that parallel to the hyperplasia of the interstitial cells, a much more precocious and pronounced differentiation of germinal cells was seen in the ovary, characterized by an earlier peak and decrease of DAZL and OCT protein immune markers. In conclusion, a reduced degree of hyperplasia and interstitial tissue in the fetal testis after 90 days of gestation suggests the existence of a more efficient mechanism regarding the synthesis of estrogen precursors as a structural or physiological difference between both fetal sexes, which warrants further investigation.

Morphometric evaluation of muscle fiber types in different skeletal muscles of rats.

The purpose of the present work was to study some morphological differences of similar muscle fiber types--classified by ATPase reactions in different muscles of rats. Morphological parameters were used as stereological techniques at light and electron microscopic level. There was a great variation in the diameter of each muscle fiber type of different muscles. The smallest diameter of type 1 myofibers of the soleus was greater than the diameter of type 1 myofibers of other muscles. The diameter of type 1 myofibers of the soleus and of the lateral part of the gastrocnemius was almost twice the diameter of type 1 myofibers of sternocleidomastoid. The lateral and medial parts of gastrocnemius had the largest 2A and 2B muscle fibers. As a whole, among the studied muscles, myofibers of postural muscles of the posterior parts of the posterior limbs had the greatest diameter. Stereological analysis at electron microscopic level revealed that there were differences in the volume density of mitochondria in the different muscles. The quantity of mitochondria was greater in the diaphragm than in the gastrocnemius, soleus and sternocleidomastoid muscles. Our results suggested that the diameter of muscle fibers is more related to the resistance the muscle is submitted than to the continuous necessity of contraction. However, the quantity of mitochondria of oxidative fibers of the diaphragm would be related to continuous necessity of contraction and high oxidative necessity of this muscle.

[Surgical staging of pulmonary carcinoma. Probability of error]. / Stadiazione chirurgica del carcinoma polmonare. Probabilità di errore.

234 patients with lung cancer and operated in Thoracic and Cardiovascular Surgery Department of Careggi Hospital in Florence have been evaluated in order to examine surgical staging accuracy in comparison with pathological staging. There is a statistically significative difference between surgical and pathological staging as a datum point. Surgeon is inclined to over-estimate the lymph-nodes involvement and the primitive tumor extension. It is important to bear in mind this bent whenever decisions of surgical strategy have to be taken.

[Risks from volatile anesthetics in operating rooms of Umbrian hospitals]. / Rischi da anestetici volatili nelle sale operatorie degli ospedali Umbri.

The present report is a research on air samples taken in the operating theatres environment in the hospitals of Umbria to control in order the concentration of anaesthetics in use and to define ambient pollution and to propose changes. The A.A. have divided operating theatres in for groups to analyze the data: 1) operating theatres where there were both systems: air change system and air intake system; 2) operating theatres where there was only the air-change system; 3) operating theatres where there was only the air intake system; 4) operating theatres where there were no systems. These data have been compared with the limit values advised by N.I.O.S.H. The lowest value of pollution have been recorded in those operating theatres with both systems. The A.A. have also compared the ethrane or other alogenated anaesthetics values in the air-change system equipped operating theatres with those (values) found in the intake-air system equipped operating theatres. The lowest values have been recorded in those operating theatres with normal air-change system. Where changes have been made to improve the operating theatres environment, the A.A. have effectuated new controls and found lower values of the anaesthetics levels. The concentration of anaesthetics appeared lower then before.