Evaluation of pulmonary maturity in bovine neonates: analysis of amniotic fluid / Avaliação maturidade pulmonar em neonatos bovinos: análise do líquido amniótico

Considering the representativeness of dairy cattle in our country, the concern about the mortality rates of the animals increases each time. Regarding to calf mortality, the Respiratory Distress Syndrome (RDS) has an important relevance during the neonatal period, and it is present in immature lungs. The amniotic fluid is in direct contact with the fetus, and it is able to offer evidence about his maturity. The aim of this study was to standardize the characteristics of the amniotic fluid, color, aspect, viscosity, quantification of lamellar body and surfactant evaluation by the Clements test and cytology, of term-born, mature and healthy calves. There were used 50 Black and White Holstein calves, which mothers were observed at calving in order to collect the amniotic fluid by puncture in the moment of exposure of the fetal membrane through the vaginal canal. Most amniotic fluid had a clear and hazy appearance due to varying degrees of viscosity and the presence or absence of clots. The Clements test could be adapted to the bovine species by the modification consisting in the addition of 3mL of amniotic fluid and 1mL of 95% ethanol. The methodology of the lamellar body count by the automated particle counter is not applicable for the bovine because of the small size of their lamellar body. The Nile Blue staining is unsatisfactory on predicting fetal maturity on the bovine species, different from cytology using Hematoxylin-Shorr stain. The presence of orange cells, increase in large amounts at the end of pregnancy. The cell stained orange counting, cells which are found in great amounts at the end of pregnancy. The present study stablished new parameters for evaluation of fetal and pulmonary maturity in the bovine species.(AU)

O objetivo desse estudo foi reunir novos dados práticos sobre a avaliação da maturidade pulmonar em neonatos bovinos, padronizando as características do líquido amniótico de bezerros maduros e hígidos, o que proporcionará a oportunidade de tratamento precoce dos animais prematuros, evitando prejuízos econômicos, principalmente quando consideramos os animais de alto valor genético. Amostras de líquido amniótico foram coletadas de 50 vacas da Raça Holandesa Preta e Branca. Corpos lamelares foram identificados por microscopia eletrônica de transmissão como estruturas de tamanho aproximado de 130nm, o que impede sua contagem em analisadores automáticos. O teste de Clements sofreu adaptações de técnica e se mostrou viável com a diluição de 3mL de líquido amniótico em 1mL de etanol a 95%. A citologia utilizando o método de Hematoxilina-Shorr, diferentemente do teste de Azul de Nilo, foi eficaz na identificação das células orangiofílicas, indicativas de maturidade fetal. Esses métodos mostraram-se originais e úteis ferramentas para a avaliação de maturidade pulmonar na espécie bovina, porém estudos com bezerros prematuros ainda são necessários.(AU)

Pulmonary surfactants and their role in pathophysiology of lung disorders.

Surfactant is an agent that decreases the surface tension between two media. The surface tension between gaseous-aqueous interphase in the lungs is decreased by the presence of a thin layer of fluid known as pulmonary surfactant. The pulmonary surfactant is produced by the alveolar type-II (AT-II) cells of the lungs. It is essential for efficient exchange of gases and for maintaining the structural integrity of alveoli. Surfactant is a secretory product, composed of lipids and proteins. Phosphatidylcholine and phosphatidylglycerol are the major lipid constituents and SP-A, SP-B, SP-C, SP-D are four types of surfactant associated proteins. The lipid and protein components are synthesized separately and are packaged into the lamellar bodies in the AT-II cells. Lamellar bodies are the main organelle for the synthesis and metabolism of surfactants. The synthesis, secretion and recycling of the surfactant lipids and proteins is regulated by complex genetic and metabolic mechanisms. The lipid-protein interaction is very important for the structural organization of surfactant monolayer and its functioning. Alterations in surfactant homeostasis or biophysical properties can result in surfactant insufficiency which may be responsible for diseases like respiratory distress syndrome, lung proteinosis, interstitial lung diseases and chronic lung diseases. The biochemical, physiological, developmental and clinical aspects of pulmonary surfactant are presented in this article to understand the pathophysiological mechanisms of these diseases.

Effects of epidermal proteins and lamellar bodies on epidermal barrier in glucocorticoid-dependent dermatitis / 中华皮肤科杂志

ObjectiveTo explore the effects of epidermal proteins and lamellar bodies on skin barrier in glucocorticoid-dependent dermatitis.MethodsTotally,60 patients with glucocorticoid-dependent dermatitis and 40 normal human controls were eligible for this study.A noninvasive method using TewameterTM was applied to determine transepidermal water loss (TEWL) value in these subjects.Tissue specimens were obtained from the lesions of 13 patients with glucocorticoid-dependent dermatitis and normal skin of 10 human controls.Subsequently,haematoxylin and eosin(HE) staining was performed to observe the histopathological changes,immunohistochemistry to detect the protein expressions of K6,K10,K14,K15,loricrin,filaggrin,involucrin in epidermis,and electron microscopy(EM) to estimate the density of lamellar bodies in tissue specimens.ResultsCompared with the normal controls,the patients displayed an elevated TEWL value (P ＜ 0.05),which suggested an impaired epidermal barrier.Histopathology of lesions revealed nonspecific inflammatorychanges withmarkeddifferencesbetweendifferentclinicaltypesofglucocorticoid-dependentdermatitis.Immunohistochemistry revealed an attenuated expression of K10,K14,loricrin,filaggrin,involucrin and abnormal expression of K15 in lesional epidermis compared with the normal epidermis (all P ＜ 0.05),hinting a suppression of epidermal differentiation and proliferation as well as an impairment of cornified envelope structure.The number and density of lamellar bodies were also reduced in lesional epidermis compared with the control epidermis.ConclusionsCompared with normal skin,the structure of skin barrier is impaired in lesions of glucocorticoid-dependent dermatitis,to restore skin barrier is essential for the treatment of this entity.