BPI-fold (BPIF) containing/plunc protein expression in human fetal major and minor salivary glands

Abstract The aim of this study was to determine expression, not previously described, of PLUNC (palate, lung, and nasal epithelium clone) (BPI-fold containing) proteins in major and minor salivary glands from very early fetal tissue to the end of the second trimester and thus gain further insight into the function of these proteins. Early fetal heads, and major and minor salivary glands were collected retrospectively and glands were classified according to morphodifferentiation stage. Expression of BPI-fold containing proteins was localized through immunohistochemistry. BPIFA2, the major BPI-fold containing protein in adult salivary glands, was detected only in the laryngeal pharynx; the lack of staining in salivary glands suggested salivary expression is either very late in development or is only in adult tissues. Early expression of BPIFA1 was seen in the trachea and nasal cavity with salivary gland expression only seen in late morphodifferentiation stages. BPIFB1 was seen in early neural tissue and at later stages in submandibular and sublingual glands. BPIFA1 is significantly expressed in early fetal oral tissue but BPIFB1 has extremely limited expression and the major salivary BPIF protein (BPIFA2) is not produced in fetal development. Further studies, with more sensitive techniques, will confirm the expression pattern and enable a better understanding of embryonic BPIF protein function.

Head morphology and degree of variation in lacerta bilineata: podarcis muralis and podarcis sicula / Morfología de la cabeza y el grado de variación en lacerta bilineata: podarcis muralis y podarcis sicula

The morphology of cephalic scales in Lacertids is organised in well defined geometrical structures. The variation of these elements is related to the underlying bone growth and morphogenesis, but it is also associated with the muscular system and the sutural dynamics. In this paper, the patterns of variation of the cephalic scales have been compared between three common Mediterranean species: Podarcis muralis, Podarcis sicula and Lacerta bilineata. The morphospace generated by the morphological relationships within the cephalic system in these three species is investigated in order to consider their degree of variation and their anatomical peculiarities. Generally, Lacerta is 64 percent larger than Podarcis, shows a relative reduction of the frontal scale, enlarged fronto-parietal structures, and stretched occipital area. L. bilineata shows the smaller degree of variation within the shape space, while P. muralis shows the highest values. The morphology of the two genera is definitely different mostly because of allometric variation. Non-allometric distinctions between the three species are subtle but detectable. The degree and pattern of variation are interpreted in terms of possible environmental pressures and of functional cranial dynamics associated with the fronto-parietal suture, respectively. In this sense, the structural relationships between bones and scales are of particular interest to further investigate ontogeny and phylogeny in reptiles.

La morfología de las escamas cefálicas en Lacértidos se organiza en estructuras geométricas bien definidas. La variación de estos elementos está relacionada con el crecimiento y la morfogénesis del hueso subyacente, pero está también es asociada con el sistema muscular y sutural dinámico. En este trabajo, son comparados los patrones de variación de las escamas cefálicas de tres especies mediterráneas comunes: Podarcis muralis, Podarcis sicula y Lacerta bilineata. El morfoespacio generado por las relaciones morfológicas con el sistema cefálico en estas tres especies se investigó con el fin de examinar su grado de variación y sus peculiaridades anatómicas. En general, Lacerta es 64 por ciento más grande que Podarcis, muestra una reducción relativa de la escama frontal, alargamiento de la estructura fronto-parietal, y estrechamiento del área occipital. L. bilineata muestra el menor grado de variación en la forma del espacio, mientras que P. muralis muestra los valores más altos. La morfología de los dos géneros es diferente principalmente debido a variaciones alométricas. Diferencias no alométricas entre las tres especies son sutiles pero detectables. El grado y el patrón de variación son interpretados en términos de las posibles presiones del medio ambiente y la dinámica funcional craneal asociada a la sutura fronto-parietal, respectivamente. En este sentido, las relaciones estructurales entre los huesos y las escamas son de particular interés para seguir investigando ontogenia y filogenia de los reptiles.