Sexual dimorphism of the extraorbital lacrimal glands in SF-1 knockout mice

Sexual dimorphism (SD) represents all the differences between males and females of the same species. SD of the murine lacrimal gland and the major effect of testosterone on its formation are well documented. Steroidogenic factor-1 (SF-1, NR5a1) is a nuclear receptor essential for the fetal development of steroid hormones producing organs and SF-1 knockout mice (Sf-1 KO) are therefore born without gonads and adrenal glands. The aim of this study was to investigate whether SD in lacrimal glands is present in the absence of exposure to sex hormones during development. Lacrimal glands from adult Sf-1 KO male and female mice without hormonal exposure, and from males that were treated with testosterone propionate (TP) prior to sacrifice, were examined. After sacrifice, glandular tissue was processed using standard histological procedures. Paraffin sections were analysed by stereology and immunostained against the androgen receptor (AR). Our results showed that there were no statistically significant differences in the mean volumes of acini, connective tissue or ductal system between males, females, and males on TP. The same pertains to the mean length of the ducts in all three groups. In the absence of sex hormones, sex chromosomes proved to be insufficient in inducing sexual dimorphism in LG. However, nuclei of the acinar cells in males on TP were positive for AR, whereas in males without TP no expression of AR was detected. Administration of TP induced the expression of AR in the nuclei of acinar cells of males but did not affect the morphology of LG. We conclude that SD in the lacrimal gland is not present in Sf-1 KO mice and this suggests that sex hormones have a major role in the development of SD in the lacrimal gland.     

Chemically synthesized solid phase oligosaccharide probes for carbohydrate-binding receptors. Interactions of the E-, L- and P-selectins with sialyl-Le(x) and O-sulphated forms linked to biotin or to polyacrylamide

There is a growing interest in chemically defined oligosaccharide reagents for identifying proteins that bind carbohydrates and determining the specificities of carbohydrate-binding proteins. Here, we compare three sets of chemically synthesized commercially available oligosaccharide conjugates as immobilized probes, for the binding signals that they elicit with known carbohydrate-binding receptors of the immune system, the E-, P- and L-selectins. The first set of conjugates is of oligosaccharides linked to biotin via a nine-carbon spacer. The second and third sets are multivalent derivatives in which the oligosaccharides are linked, via a three-carbon spacer to poly[N-(2-hydroxyethyl)acrylamide] (PAA) or to biotinylated PAA with an average of 20% substitution of the hydroxyethyl-amide groups by carbohydrate. The conjugates were immobilized on streptavidin-coated microwells if biotinylated, otherwise by drying in uncoated wells. The most robust binding curves, overall, were with the biotinylated PAA derivatives of the ligands immobilized on streptavidin wells. These reagents have permitted a reevaluation of selectin binding signals elicited by sialyl-Lewis(x) (SLe(x)) analogues having sulphate at position 6 of the galactose (6'SuSLe(x)) or of the N-acetylglucosamine (6SuSLe(x)). The results clarify the role of 6SuSLe(x), rather then 6'SuSLe(x), as a ligand for the selectins.     

A critical approach to gamma variate fit of radionuclide-angiography pulmonary histograms

Radionuclide-angiography (RNA_ left-to-right intracardiac-shunt quantification algorithms, based on the part-by-part fit technique and the use of a so-called gamma variate model function (GVF), were tested via simulation analysis using data obtained from normal subjects. A good bolus of radioindicator was obtained by administering it directly into the vena subclavia. Normal subjects were defined as those having pulmonary histograms (PH) with no visible distortion caused by a shunt. Pure, non-superimposed data on the downslope of the PH curves, which are lost in presence of a shunt, proved to be appropriate reference values for testing the accuracy of results of standard shunt quantification algorithms. A generalized four-parameter GVF was introduced in order to extend the flexibility of the model function. The use of the three-parametric GVF to reconstruct the downslope of the PH curve out of the upslope data proved to be inadequate. This reveals an evident source of error in algorithms that calculate the shunt contribution by fitting GVF parameters to so-called difference-curve data. It is concluded that the inherent restricted statistical weight of RNA data prevents accurate results being obtained from standard RNA-shunt-assessment algorithms.     

Effects of high doses of testosterone propionate and testosterone enanthate on rat seminiferous tubules — a stereological and cytological study

The effects of exogenous testosterone on various testicular variables has become of increasing significance because of its potential use in male contraception. For this reason, high doses of two testosterone esters [testosterone propionate (TP) and testosterone enanthate (TE)] were used in a study of their influence on the morphology, length and curvature of the seminiferous tubules of the rat testis, and on cytological smears of the seminiferous tubules epithelium. TP was given for 14 days (3 mg/100 g body weight, i. m.) to assess the acute effects of testosterone on the seminiferous tubules. TE was administered for 60 days (in the same manner as TP) to study possible chronic effects on the rat testis. After TP and TE treatment the seminiferous tubule epithelium showed disorganization and desquamation of spermatogenic cells. In the TP-treated testes the tubules lined with Sertoli cells only were observed. The values for the length and curvature of seminiferous tubules of the TP- and TE-treated rats were significantly reduced (p<0.001). All these changes were observed earlier in the TP-treated than in the TE-treated animals. In cytological smears of the testis of the TP- and TE-treated rats an increase of vacuoles and residual bodies in Sertoli cell cytoplasm was noted. In addition, a reduction of spermatogenic cells, particularly sperms, was manifest in the smears after treatment. Large groups of Sertoli cells were seen in the smears from these testes.The study was supported by a Grant for Scientific Research No. 3-01-041 from the Ministry of Science, Technology and Informatics of the Republic of Croatia     

Nasal challenge with histamine decreases nonspecific bronchial reactivity in workers exposed to respiratory irritants

BACKGROUND: A link ("naso-bronchial reflex") between nasal and bronchial reactivity seems to exist. The effect of nonspecific nasal challenge (standing for the exposure to irritative stimuli at the workplace) on lung function indices and nonspecific bronchial reactivity is not known. METHODS: In 80 healthy workers (age: 36.0 +/- 8.6 years) continuously exposed to acceptable levels of different respiratory irritants (for more than 2 years) nasal challenge was performed by spraying doubling concentrations of histamine (0.0625-16.0 mg/mL, doses of histamine: 7.8 micrograms-2.08 mg) into each nostril. Before and immediately after nasal challenge spirometry and the bronchoprovocation test with histamine (0.5-128 mg/mL) was performed. RESULTS: Although nasal challenge with histamine had not reduced airway caliber (before nasal challenge vs. following nasal challenge: FEV1 3.8 +/- 0.8 vs. 3.7 +/- 0.8 L, and MEF50 4.3 +/- 1.4 vs. 4.3 +/- 1.4 L/s, mean +/- SD, respectively), it had significantly reduced nonspecific bronchial reactivity in 30.2% of the irritant-exposed subjects. CONCLUSIONS: Nasal challenge with histamine decreases nonspecific bronchial reactivity in workers occupationally exposed to respiratory irritants. Thus, a methodological implication would be that these two tests should not be performed consecutively in less than 2 hr in the same subjects.     

Lamina propria of sex cords in human fetal testis: an immunohistological and stereological study

Testicular peritubular cells are located in the lamina propria of seminiferous tubules. These cells, significantly contributing to the basal membrane of seminiferous epithelium, have been studied in a number of species. However, there is a lack of data on the development of the lamina propria in the human testis. The aim of our survey was to investigate the characteristics of the lamina propria and, in particular, peritubular cells in the fetal human testes by immunohistological and stereological methods. Therefore, testes (14–39 weeks of gestation, n=45) were dissected and fixed in a 4% buffered paraformaldehyde solution. Several pieces of each testis were embedded in paraffin and processed for immunohistochemical and stereological analysis. All investigated testes have shown sex cords in the process of development and differentiation. Morphologically, peritubular cells in the lamina propria can be divided into two types: fibroblast-like (FL) and myoid-like (ML) type (cells which much resemble mature myoid cells). By immunohistochemistry, both FL and ML cells are found to be strongly positive for the intermediate filament desmin, but negative for -smooth actin. While FL cells intensively express Ki-67 demonstrating proliferative activity, ML cells are found to be negative. The basement membrane of sex cords as well as the blood vessels of the interstitium show strong positivity to collagen IV and laminin. Concerning the correlation between the appearance of the investigated antigens with the gestational age, all antigens have been expressed (in the manner described above) already in the 14th week of gestation. The stereological analysis of the number (Nv) and volume (Vv) of peritubular cells indicates a pulsatile development of these cells in the lamina propria of the human fetal testis. While the stereological variables determined for FL cells show a gradual decrease, the same variables determined for ML cells demonstrate a successive increase. It appears that the lamina propria of the fetal human testes shares many of the properties previously discovered in rodents.     

Synchronous primary carcinomas of the ampulla of vater and ascending colon in a patient with multiple flat adenomas

Multiple primary cancers occurring in the same patients have been reported to represent 1.8–3.9% of all cancers. The majority of all patients reported to have had a combination of simultaneous neoplastic changes in the ampulla of Vater and the colon showed familial adenomatous polyposis (FAP) syndrome. Variants of familial adenomatous polyposis coli are: attenuated adenomatous polyposis coli (AAPC, previously also known as flat adenoma syndrome) and multiple adenoma coli. AAPC is characterized clinically by many, but usually fewer than 100, colonic lesions that are characteristically slightly elevated and plaque-like, with a reddish surface and sometimes central depression. Genetically it represents an extremely rare variant of FAP. Another group of individuals, so-called multiple adenoma patients, have a phenotype similar to AAPC, but most have no demonstrable germ-line adenomatous polyposis coli mutation, as do patients with FAP or AAPC. However, there have been only a few reports that discussed concurrent neoplastic changes in the ampulla of Vater and colon in patients with multiple colonic flat adenomas, but without the florid phenotype of classical FAP. We present rare clinical course of a patient with multiple (more than 60) flat adenomas in the proximal colon and two primary cancers: of the ampulla of Vater and of the ascending colon. This patient and his family history did not show polyposis compatible with FAP or hereditary nonpolyposis colorectal cancer (HNPCC) syndrome.     

Multivariate analysis of preoperative and postoperative neutrophil-to-lymphocyte ratio as an indicator of head and neck squamous cell carcinoma outcome

Recent publications have highlighted a greater utility of routine blood tests in patients with various cancers than previously assumed. It appears that the neutrophil-to-lymphocyte ratio (NLR) may be a good predictive biomarker for overall survival (OS) and disease-free survival (DFS). Preoperative and postoperative NLR data for patients with head and neck cancers have yet to be established. The aim of this study was to evaluate the preoperative and postoperative NLR in 182 patients with head and neck squamous cell carcinoma and to determine the association of NLR with OS and DFS. The statistical analysis of OS and DFS and their predictors was performed using Kaplan–Meier survival analysis and multivariate Cox proportional hazards regression analysis, with factors including age, sex, alcohol and tobacco use, tumour location, treatment after surgery, and lymphocyte and neutrophil counts. Longer OS was significantly associated with not consuming alcohol, preoperative neutrophil and lymphocyte counts, preoperative NLR, and the difference between the preoperative and postoperative NLR (P = 0.016). Longer DFS was significantly associated with not consuming alcohol, preoperative neutrophil and lymphocyte counts, postoperative NLR, and the difference between preoperative and postoperative NLR (P = 0.028).     

Temporal reduction of LATS kinases in the early preimplantation embryo prevents ICM lineage differentiation

Cellular localization of the Yes-associated protein (YAP) is dependent on large tumor suppressor (LATS) kinase activity and initiates lineage specification in the preimplantation embryo. We temporally reduced LATS activity to disrupt this early event, allowing its reactivation at later stages. This interference resulted in an irreversible lineage misspecification and aberrant polarization of the inner cell mass (ICM). Complementation experiments revealed that neither epiblast nor primitive endoderm can be established from these ICMs. We therefore conclude that precisely timed YAP localization in early morulae is essential to prevent trophectoderm marker expression in, and lineage specification of, the ICM.