Glial fibrillary acidic protein (GFAP) in ependymal cells during development. An immunocytochemical study

Human ependymal cells show positive immunostaining for glial fibrillary acidic protein (GFAP) at one stage of the fetal development. The reaction seems to coincide with maturation of the epithelial layer and development of cilia. Two types of reactive cells are present: epithelial and tanycytes. The GFAP-positive reaction in both these cells is transient, appearing at different times and with different patterns in the various regions of the ventricular system. In order to explain the presence of detectable GFAP in developing ependymal cells and its absence in mature cells, it is proposed that either the synthesis of detectable amounts of GFAP occurs only at a stage of ependymal cell maturation, or that the intermediate filaments assembled in developing ependymal cells are antigenically distinct from those of the mature cells. The present findings indicate that tanycytes are not an immature form of ependymal cells but that they develop parallel to the epithelial cells. The role of the tanycytes remains obscure, but it is suggested that they are not related to radial glia.     

X;14 translocation:an exception to the critical region hypothesis on the human X-chromosome

We report on a family in which an X;14 translocation has been identified. A phenotypically normal female, carrier of an apparently balanced X-autosome translocation t(X;14)(q22;q24.3) in all her cells and a small interstitial deletion of band 15q112 in some of her cells had 2 offspring. She represents a fifth case of balanced X-autosome translocation with the break point inside the postulated critical region of Xq(q13 q26) associated with fertility. The break point in this case is located in Xq22, the same band as in four previously published exceptional cases. In most of her cells, the normal X was inactivated. Her daughter, the proposita, has an unbalanced karyotype 46,X,der(X), t(X;14)(q22;q24.3)mat, del(15)(q11.1q11.3)mat. She is mildly retarded and has some Prader-Willi syndrome manifestations. She has two normal 14 chromosomes, der(X), and deletion 15q11.2. Her clinical abnormalities probably could be attributed to the deletions 15q and Xq rather than 14q duplication. In most of cells, der(X) was inactivated. We assume that spreading of inactivation was extended to the 14q segment on the derivative X. Late replication and gene dose studies support this view. Another daughter, who inherited the balanced X;14 translocation and not deletion 15 chromosome, is phenotypically normal.     

Histamine release, an undesired effect of thrombin inhibitors with basic character, is mediated through direct activation of G(i) proteins

The common structural feature of LK direct thrombin inhibitors is a strong basic group attached to the azaphenylalanine scaffold, which is important for the appropriate interaction at the thrombin active site. Our previous results have shown that this basic group could be responsible for a reduction of tracheal air flow and a fall of mean arterial pressure in anaesthetized rats, an undesired effect of direct thrombin inhibitors which correlated with their ability to release histamine from mast cells. In the present study, we investigated the mechanism of LK direct thrombin inhibitors-induced histamine release from rat peritoneal mast cells. We demonstrated that thrombin inhibitors with basic character (LK-732, LK-639 and LK-6063) provoked release of histamine from mast cells, while less basic analogs (LK-658, LK-633 and LK-6062) had no effect. Histamine released by LK-732 and LK-639 was suppressed by removal of sialic acid residues by neuraminidase and by pertussis toxin, an inhibitor of G(i) protein activity. Additional demonstration that G proteins are the targets of LK-732 and LK-639 was provided by the increase of GTPgammaS binding rate to G proteins in rat brain cortical membranes. Our results indicate that basic direct thrombin inhibitors LK-732 and LK-639 provoke release of histamine from mast cells by direct activation of G(i) proteins through the similar biochemical pathway as basic secretagogues.     

Physical and thermal characterisation of chiral omeprazole sodium salts

The physical properties of drug substances may affect stability, manufacturing, dissolution and bioavailability. Variations in the degree of crystallinity in a pharmaceutical substance may exhibit physicochemical differences that impact at therapeutic, manufacturing, commercial and legal levels, yet no reference has been found on the physical properties of micronised omeprazole. This study reports on the physical and thermal characterisation of the sodium salts of S- and R-omeprazole, using diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), microthermal analysis (microTA) and powder X-ray diffraction (XRPD). DSC experiments were performed in order to determine not only their thermal stability, but also the thermal history of both forms. SEM results indicate similar morphology, particle size and shape of powdered drug, while, microTA of processed discs shows different topographical images for S- and R-omeprazole, exhibiting a smoother surface for the S-form, indicative of the smoother particle size not evident in the SEM results. The low level of crystallinity of both enantiomers was confirmed by DRIFT spectroscopy and XRPD. Thermal stability by DSC of S- and R-omeprazole sodium salts was superior to that of the neutral omeprazole. This study has examined the physical and thermal properties of both forms and in highlighting their differences provides an explanation for the potential differences in bioavailability and therapeutic efficacy.     

Maternal identity change as a consequence of antenatal hospitalization

Despite low fertility rates in Western countries, maternity remains one of the major goals of women from various socioeconomic backgrounds. While most women will have low-risk pregnancies, common serious disorders of pregnancy, such as preeclampsia, premature rupture of the membranes, placenta previa, or fetal growth restriction, may compromise maternal and infant outcomes. The experiences of urban and rural women in Australia who have had difficulties in maintaining their pregnancies are analyzed in this article. We study the impact of individual and social factors that facilitate or impede women's adjustment to the risks associated with these disorders. The analysis of in-depth interviews with 27 women hospitalized antenatally indicates that most women were unfamiliar with the diagnoses and acted as passive "decision takers," complying with medical advice to remain in the hospital. Admission to a tertiary hospital ward that provided care to women with pregnancy disorders promoted the formation of a new identity, that of a woman whose pregnancy did not follow the expected path. Further, hospitalization offered women the opportunity to interact with others in similar difficult situations and, hence, feel less isolated.     

Association between allelic variants in cytokine genes and preeclampsia

OBJECTIVE: The purpose of this study was to examine the relationship between cytokine genotypes and preeclampsia. STUDY DESIGN: We conducted a case-control study that examined cytokine genotypes among 150 primiparous preeclamptic women and 661 primiparous, normotensive women. Analyses were adjusted for age, prepregnancy cigarette smoking, and education. RESULTS: Preeclamptic white women were more likely than normotensive white women to carry the up-regulating tumor necrosis factor-alpha-308 A/A (odds ratio, 4.1; 95% CI, 1.1-15.3) genotype. Both black and white women with preeclampsia were more likely than normotensive control subjects to carry the interleukin-1alpha-producing-4845 G/G genotype (black odds ratio, 11.6; 95% CI, 1.5-89.3; white odds ratio, 1.7; 95% CI, 0.7-3.9), -889 C/C genotype (black odds ratio, 5.1; 95% CI, 0.6-41.6; white odds ratio, 1.9; 95% CI, 0.8-4.7), and the interleukin-1alpha-4845/interleukin-1alpha-889/interleukin-1beta-3957 GCC/GCC haplotype (black odds ratio, 3.4; 95% CI, 1.3-8.7; white odds ratio, 2.1; 95% CI, 1.4-3.2). CONCLUSION: Cytokine genotypes were associated with preeclampsia and may identify women who are at high risk for preeclampsia.     

Development and validation of RP-HPLC method for cetrimonium bromide and lidocaine determination

The simple and rapid RP-HPLC method, for the simultaneous determination of lidocaine and cetrimonium bromide in the presence of pellet color corrigent, was developed. Separations were performed on a Beckman Ultrasphere ODS 4.6 mm x 15 cm, 5 microm particle column at 40 degrees C. The mobile phase consisted of water phase and acetonitrile (72:28 V/V), pH value of the mobile phase was adjusted to 2.0 with 85% ortophosphoric acid. Bisacodil was used as an internal standard. The flow rate was 1 ml/min and UV detection was performed at 208 nm. The proposed RP-HPLC method was validated and all the parameters for the validation of the method are given. According to the obtained results, the developed method was found to be suitable and accurate for the determination of these drugs in commercial formulations.