Serological Examination of Some Strains That Are in the Mycobacterium avium-intracellulare-scrofulaceum Complex But Do Not Belong to Schaefer's Serotypes

One hundred strains belonging to the Mycobacterium avium-intracellulare-scrofulaceum (MAIS) complex but not agglutinating with antisera type-specific for Schaefer''s 23 MAIS serotypes were examined using antisera against seven other such strains. Four of the 100 strains were found to be of the same serotype as one of the 7 against which antisera were prepared; 4 other strains were of the same serotype as another of those against which antisera were prepared. Although the strains against which antisera were prepared were serologically distinct from each other, no strains serologically identical to 5 of them were found. This suggests that numerous serotypes might have to be defined if strains such as those examined are to be assigned to their respective serotypes.     

Clustering of apoptotic cells via bystander killing by peroxides.

Clustering of apoptotic cells is a characteristic of many developing or renewing systems, suggesting that apoptotic cells kill bystanders. Bystander killing can be triggered experimentally by inducing apoptosis in single cells and may be based on the exchange of as yet unidentified chemical cell death signals between nearby cells without the need for cell-to-cell communication via gap junctions. Here we demonstrate that apoptotic cell clusters occurred spontaneously, after serum deprivation or p53 transfection in cell monolayers in vitro. Clustering was apparently induced through bystander killing by primary apoptotic cells. Catalase, a peroxide scavenger, suppressed bystander killing, suggesting that hydrogen peroxide generated by apoptotic cells is the death signal. Although p53 expression increased the number of apoptoses, clustering was found to be similar around apoptotic cells whether or not p53 was expressed, indicating that there is no specific p53 contribution to bystander killing. Bystander killing through peroxides emitted by apoptotic cells may propagate tissue injury in different pathological situations and be relevant in chemo-, gamma-ray, and gene therapy of cancer.     

Prenatal stress and glucocorticoid effects on the developing gender-related brainProceedings of Xth International Congress on Hormonal Steroids, Quebec, Canada, 17–21 June 1998.

Hormonal and neurotransmitter environment of nondifferentiated cells in the developing brain determines many of gender-specific behavioural and neuroendocrine functions. Early postnatal and long-term effects of maternal stress or prenatal glucocorticoid on sex-related peculiarities of the brain morphology, biogenic monoamine turnover, testosterone metabolism, hypothalamic noradrenaline (NA) and adrenocortical responses to an acute stress were studied in Wistar rat offsprings. Maternal stress (1 h immobilization daily for gestational days 15–21) prevented development of sexual dimorphism in neuronal cell nuclei volumes in suprachiazmatic nucleus (SCN) in 10 day old pups. That was associated with a disappearance of male–female differences in NA and 5-hydroxytryptamine turnover in the preoptic area (POA) and dopamine (DA) turnover in the mediobasal hypothalamus (MBH) by decreasing them in male pups. Hydrocortisone acetate (5 mg daily during the last week of pregnancy) produced changes in NA turnover in the POA of males and females which were quite similar to those after maternal stress. Changes in aromatase and 5-reductase activities in the POA of male pups were quite opposite as affected by maternal stress or prenatal glucocorticoid. Sexual differences in 5-reductase activity in the MBH appeared due to its increase in prenatally stressed male pups. In contrast to adult males, in adult females maternal stress did not restrict hypothalamic NA and blood plasma corticosterone response to acute stress (1 h immobilization). Our findings on morphology and functions of gender-related developing brain areas stand in correlation with modifying effects of maternal stress and prenatal glucocorticoid on behavior and neuroendocrine regulations.     

Uptake of testosterone by tissues of human fetal prostatic rudiments

The common and specific uptake of 3H-testosterone (3H-T) by tissues of urogenital sinus (UGS) and bladder (BL) in human 10-12 weeks fetuses was studied. The values of common and specific 3H-T uptake in UGS were significantly higher than those in BL. A high specific uptake of labeled hormone was also detected in UGS mesenchyme separated from epithelium. The authors did not reveal any sexual dimorphism of 3H-T uptake by UGS tissues.     

Sexual Behavior,Profile of Steroid Hormones,and Morphology of the Medial Preoptic Nuclei in F1 Male Rat Progeny Prenatally Exposed to Low-Dose Bisphenol A

Neurophysiology - Long-term effects of maternal treatment of Wistar rats with low doses of bisphenol A (BPA) on sexual behaviors, morphology of the medial preoptic nuclei (MPNs) of the...     

Space-time sequence and mosaicism of neurogenesis in the CA1 field of the mouse hippocampus

Pregnant CBA mice were given a single injection of 3H-thymidine (3H-T) (10 microCi/g) on days 11-19 of pregnancy. The mouse progeny was sacrificed on the first day of postnatal life. Brain was embedded into paraffin and durcupan. Radioautographs of paraffin and semithin sections were prepared and employed for mapping the site of intensely labeled neurons (ILN) in the CAI area of the hippocampus (H). ILN appeared in the CAI area after 3H-T injection, namely on embryonic day 12 (E 12). The ILN number reached a maximum after isotope injection on 2 14-15 and then dramatically fell down. The neurogenesis in the suprapyramidal layer of the CAI area slightly outstripped the neurogenesis in the pyramidal and infrapyramidal layers. At early times of the experiment the CAI area exhibited the predominance of single ILN, whereas at late times paired ILN prevailed. That fact might be linked with the replacement during the neurogenesis of asymmetric critical mitoses of the germinative neuronal precursors by symmetric critical mitoses. Analysis of the ILN distribution in the CAL area revealed mosaic clusters of ILN alternating with unlabeled or mildly labeled neurons. Those groups were most remarkable in mice injected with 3H-T on E 14 and E 15. The mosaicism of the neurogenesis in the H is regarded as the result of heterochronous neuronal production by local parts of the germinative zone, each of which builds up a separate radial segment of the H.     

The determination of the optimal inoculation dose of an oral cholera chemical bivalent vaccine in a controlled experiment

276 volunteers aged 19 years and over were placed under observation in the course of the trial of oral cholera vaccine in tablets, containing choleragen toxoid, O-antigens of serovars Inaba and Ogawa and a number of Vibrio cholerae exoenzymes, for safety, reactogenic properties and immunological effectiveness. The vaccine was found to produce no reactions in a dose of 1-4 tablets; the administration of 3 tablets (300,000 binding units of the toxoid and 10,000 units of O-antigens, serovars Inaba and Ogawa) was shown to induce the most intensive synthesis of both antitoxins and vibriocidal antibodies in the blood sera of volunteers, as well as IgA coproantibodies. The oral vaccine was found to have an advantage over parenteral vaccines due to the absence of reactogenic properties and the formation of local immunity: coproantibodies appeared in 80% and 9% of the vaccinees respectively.     

Increase of noradrenaline contents in the hypothalamus of neonatal female rats under the effects of 4-hydroxyestradiol-17beta

Catecholamine content was studied in hypothalamus of neonatal Wistar female rats treated with 4-hydroxyestradiol-17 (4-OH-E2) in a dose of 10 mg for 1-5 days of life. 4-OH-E2 induced a reliable increase in hypothalamic noradrenaline level in 24 h after the last injection, but not on the 7th, 10th or 12th postnatal days. There was no change in dopamine level. We have postulated a relationship between the increase in hypothalamic noradrenaline content induced by 4-OH-E2 and defeminization effects of 4-OH-E2 on the developing brain of female rats.     

Loss of anion transport without increased sodium absorption characterizes newborn porcine cystic fibrosis airway epithelia

Defective transepithelial electrolyte transport is thought to initiate cystic fibrosis (CF) lung disease. Yet, how loss of CFTR affects electrolyte transport remains uncertain. CFTR?(/)? pigs spontaneously develop lung disease resembling human CF. At birth, their airways exhibit a bacterial host defense defect, but are not inflamed. Therefore, we studied ion transport in newborn nasal and tracheal/bronchial epithelia in tissues, cultures, and in vivo. CFTR?(/)? epithelia showed markedly reduced Cl? and HCO?? transport. However, in contrast to a widely held view, lack of CFTR did not increase transepithelial Na(+) or liquid absorption or reduce periciliary liquid depth. Like human CF, CFTR?(/)? pigs showed increased amiloride-sensitive voltage and current, but lack of apical Cl? conductance caused the change, not increased Na(+) transport. These results indicate that CFTR provides the predominant transcellular pathway for Cl? and HCO?? in porcine airway epithelia, and reduced anion permeability may initiate CF airway disease.