Significance of keratin 13 and 6 expression in normal, dysplasic and malignant squamous epithelium of pyriform fossa.

It has been suggested that cytokeratin 13 is a useful marker of malignancy. We examined normal squamous cell epithelia, hyperplasia, dysplasias of various grades, intraepithelial neoplasia and invasive squamous cell carcinomas of the pyriform fossa using K13 and KL1. Positive staining for K13 was seen in all normal or hyperplastic benign epithelia, was inconstant in dysplasia, and intraepithelial neoplasia and carcinoma was negative. KL1 expression is constant and non significant. These results suggest that tumour cells are unable to synthesize keratin 13 a finding which may be valuable in surgical pathology.

Variation and frequency of cytokeratin polypeptide patterns in human squamous non-keratinizing epithelium.

The squamous non-keratinizing epithelium of the human upper digestive tract was analyzed for keratin-like cytoskeletal proteins (cytokeratins) by both high resolution one- and two-dimensional gel electrophoresis. The Triton/high salt-insoluble portion of pure epithelial homogenates contains a number of SDS- and urea-extractable polypeptides, whose two-dimensional gel pattern (NEpHG/SDS) typically represents a defined subset of human cytokeratins. The cytoskeletal preparations of epithelial tissue samples obtained from different individuals were found to be uniform with respect to their content of cytokeratin polypeptides 55.0 kD/basic, 52.0 kD/acidic, and 49.0 kD/acidic. However, we have observed that four basic members of apparent molecular weight 60.0, 59.0, 56.5, and 56.0 kD occur at an inconstant rate. Consequently, the cytokeratin polypeptide patterns appeared highly variable as a result of the presence of constant plus compositionally different subsets of inconstant members. From the analysis of cytoskeletal portions of more than 300 individual tissue samples we demonstrate eight different keratin-like polypeptide patterns including their frequencies and propose the existence of no more than nine. These, most probably, encompass all the possible inter-individual variations to which the cytokeratins of this type of epithelium will combine for forming intermediate-sized filaments in vivo. We furthermore hypothesize that the observed variation of cytokeratin patterns may reflect a polymorphism of genes coding for the variable keratin-like polypeptide members.

[Receptors for steroid hormones apart from breast cancer. Practical value]. / Les récepteurs des hormones stéroïdes en dehors des cancers du sein. Intérêt pratique.

The steroid receptor (ER, PgR) content of breast cancer specimens is now widely used as an indicator for hormone sensitivity which is a prerequisite for endocrine therapy. Is it conceivable to extend this steroid receptor determination to other types of tumors in order to select patients who would eventually benefit from an hormonal therapy? It seems that most normal or tumoral tissues contain detectable amount of steroid receptors. The values of each receptor comprise a continuum from very low to relatively high, suggesting that previous considerations of hormone dependence on the basis of presence or absence of hormone receptors may be oversimplified. The steroid receptor concentrations are however higher in target tissues, and could be of clinical interest in endometrium and prostatic cancers. The date are however insufficient to draw firm conclusions regarding their usefulness for treatment.

Characterization and distribution of neutral and acidic mucins in the alimentary canal of an Indian freshwater major carp, Catla catla (Hamilton) by histochemical methods.

The distribution and chemical nature of acid and neutral mucins in the various regions of the alimentary canal of Catla catla (Ham.) have been studied. Both acid (sulfated and non-sulfated) and neutral mucins have been found to occur as a mosaic of complex substances in the different mucous cell types (secretory and non-secretory--both mature and immature) in the various regions of the alimentary canal (buccopharynx, oesophagus, intestine, and rectum). Acid mucin (both sulfated and non-sulfated) of the secretory and mature non-secretory mucous cells in the buccopharyngeal and oesophageal regions, however, predominates since these 2 regions are known to participate actively in food lubrication while the sulfated acid mucin keeps the internal mucosa moist. Mucous mother cells which originate from the multipotent progenitor cells contain exclusively neutral mucin in the form of neutral mucopolysaccharide granules. In the course of development these mucous mother cells are gradually pushed towards the periphery of the mucosa and transformed into mature and secretory mucous cells through an intermediate stage--the immature mucous cells. The latter cells during development synthesize intact acid mucopolysaccharide granules which ultimately fuse to produce a compact mass of mucin (both acid and neutral) in the mature and secretory mucous cells.

Mode of delivery and the lecithin/sphingomyelin ratio.

Babies born by elective Caesarean section are more likely to develop the respiratory distress syndrome that babies born vaginally. We studied the amniotic fluid and pharyngeal lecithin/sphingomyelin (L/S) ratios in three groups of babies born at term: 20 were delivered vaginally after elective induction of labour; 20 were delivered by elective Caesarean section; and 14 by Caesarean section after spontaneous onset of labour. Babies born after induction of labour had higher pharyngeal L/S ratios than babies born by elective Caesarean section. Those born by Caesarean section after spontaneous onset of labour had significantly higher pharyngeal L/S ratios than those in both of the elective delivery groups. There were no significant differences in the amniotic fluid L/S ratios of the two groups who underwent elective delivery. Regression analysis showed a significant relationship between length of labour and increase in the L/S ratio. These results indicate that, during labour, there is a release of fetal lung surfactant into the airways.

Gastric shake test and pharyngeal lecithin/sphingomyelin ratios in new born infants.

Gastric shake test and pharyngeal lecithin/sphingomyelin ratios were measured in newborn infants with respiratory difficulties, and in low birth weight infants in the immediate neonatal period. Both tests were useful in distinguishing infants with idioathic respiratory distress syndrome from those with respiratory difficulty due to other causes. However, in six infants with idiopathic respiratory distress syndrome, the pharyngeal lecithin/sphingomyelin ratio indicated mature lungs, and in three of these, the gastric shake test showed the presence of surfactant. Five of these six infants had been delivered by emergency lower segment caesarean section because of maternal complications, which might account for the discrepancy between the laboratory results and the clinical condition of the patient.

A simple and rapid determination of the lecithin/sphingomyelin (LS) ratio in amniotic fluids and in pharyngeal aspirates of newborn infants.

A simple, rapid method for the routine determination of the lecithin/sphingomyelin (L/S) ratio in amniotic fluid and/or in pharyngeal aspirate of the newborn has been developed. In 33 samples of amniotic fluid at various gestational ages, an L/S ratio corresponding to the fetal age was found: in 16 samples of biochemically immature amniotic fluid (gestation age less than 34 weeks) the mean of the ratio was 1.26 and in 17 samples of mature amniotic fluid (gestation age greater than 35 weeks) the mean value was 3.02. Pharyngeal aspirates of 55 non-selected newborn were examined by the same method. The L/S ratio of 39 infants (gestation age greater than 38 weeks) gave a mean value of 7.3 and that of 16 premature infants (gestation age less than 37 weeks) a mean value of 5.5. In none of these cases did RDS develop after birth. The results suggest that the method is useful for the determination in both amniotic fluid and pharyngeal aspirate.

Neuroendocrine embryology and the APUD concept.

In the Vertebrata the great majority of cells producing hormonal peptides belong to the APUD series and share its distinctive cytochemical and ultrastructural characteristics. According to the concept all members of the series are to be regarded as derivatives of neuroectoderm or of specialized (placodal) ectoderm. For most of the APUD cells this criterion is fulfilled in that their origin from neural tube, neural ridges or neural crest can be considered proven. Complete proof is not yet available for the APUD cells of the gastrointestinal tract and pancreas, and indeed much contrary evidence can be cited. Despite the latter, our embryological studies show: (1) that the hypothalamohypophyseal complex is wholly neuroectodermal; (2)that the chronology of neural crest dispersion is such that this tissue could be responsible for observed APUD cell contributions to the foregut; (3) that placodal ectoderm makes important contributions to pharyngeal pouch endocrine derivatives in birds and mammals; and (4) that the amphibian parathyroid gland is derived from the same layer of neural ectoderm as the hypothalamo-hypophyseal axis. Supporting immunocytochemical studies indicate that peptides belonging to the APUD series are more widely distributed than hitherto recognized and it is concluded: (1) that the whole of peptide endocrinology is neuroendocrinology; and (2) that the APUD cells, with a few cells hitherto regarded as being outside the series, form a third (Endocrine) division of the nervous system to add to the existing Somatic and Autonomic divisions.