Decreased H2O2 in exhaled breath condensate during pregnancy--feasible effect of 17beta-estradiol.

Since pregnancy is known to favor systemic generation of reactive oxygen species, this study was designed to assess the levels of exhaled hydrogen peroxide (eH2O2), serum progesterone (PG), 17beta-estradiol (E2) and systemic oxidative parameters in 20 pregnant women between 15th and 28th gestation week and 23 healthy, eumenorrheic women. Exhaled breath condensate H2O2 was assessed fluorometrically with homovanillic acid. Exhaled H2O2 levels were lowered in pregnancy (median Me 0.13 microM) compared with follicular (Me 0.29 microM) or luteal phase (Me 0.26 microM; p<0.05 vs. both). The follicular H2O2 tended to exceed luteal phase. Whole blood chemiluminescence was increased approximately ten fold in pregnancy. E2 markedly decreased chemiluminescence of isolated polymorphonuclear leukocytes. In vitro ferric reducing ability of plasma and 2,2-diphenyl-1-picryl-hydrazyl scavenging assay were not affected by E2 or PG. Decreased exhaled H2O2 during pregnancy, despite of the increased oxidative capacity of peripheral phagocytes, might be ascribed to the magnitude of increased 17beta-estradiol levels.

Arteriovenous fistula of the kidney: a case report of 47-year-old female patient treated by embolisation.

Arteriovenous fistulas of the kidney are rare. They may be acquired, idiopathic or arise in congenital arteriovenous malformations. There are only few reports in the current literature describing the successful embolisation of idiopathic arteriovenous fistulas. We report a 47-year-old hypertensive female patient with a successfully embolised arteriovenous fistula. Diagnosis was made on the basis of colour duplex Doppler examination and this method enabled further successful embolisation of the fistula.

Can melatonin regulate the expression of prohormone convertase 1 and 2 genes via monomeric and dimeric forms of RZR/ROR nuclear receptor, and can melatonin influence the processes of embryogenesis or carcinogenesis by disturbing the proportion of cAMP and cGMP concentrations? Theoretic model of controlled apoptosis.

The presented model of controlled apoptosis has been based on the assumption that correct information exchange between an organism as a whole, and each of its cells is conditioned by mutual proportions of cAMP and cGMP concentrations (CcAMP, CcGMP), according to the formula CcAMP x CcGMP = 'a' (constant). The regulation of balance of these 'second messengers' in a cell and an extracellular space would depend on the mutual proportions of concentrations of Melatonin and monomers of Melanin. These indoloderived compounds could be the activators of the transcription factors i.e. RZR and NFkappa-B, regulating the expression of Prohormone Convertase (PC) gen and Nitric Oxide Synthase (NOS) gen, respectively. Additionally, maternal Melatonin and Nitric Oxide (NO), being able to pass through trophoblast or placenta freely, would play decisive role in the synchronization of embryogenesis and intrauterine development of the fetus. In case of an embryo or a fetus, the result of CcAMP and CcGMP multiplication, different from the proper constant 'a'-value, would mean occurrence of disorders in the structure and functioning of the cellular tensegrity system and, in consequence, disturbances in the intercellular information exchange. It would lead to deviation in cellular metabolism, oriented cell movement, uncontrolled apoptosis, and as a consequence, would lead to the development of fetal defects. In case of a child or an adult, a sudden occurrence and prolongation of such disturbances in CcAMP-CcGMP proportions would induce a process of apoptosis of normal cells and an initiation of a cancerogenesis. On the other hand, the recovery of equilibrium in the information exchange system would initiate apoptosis of neoplastic cells, and simultaneously, proliferation of connective tissue cells. According to the presented hypothesis, a decrease in CcAMP and destabilization of the CcAMP-CcGMP balance in an embryo or a fetus would result from relatively excessive amounts of maternal Melatonin (monomers) in fetal circulation, while a decrease of CcAMP and destabilization of the CcAMP-CcGMP balance in a child or an adult would be a consequence of relatively insufficient amounts of Melatonin (dimers) in an organism. It seems possible, that determination of both CcAMP and CcGMP would enable an early detection of high risk of developmental defects occurrence in an embryo or a fetus and neoplastic processes in a child or an adult. This method might also be considerably useful in monitoring a safe substitutional hormonotherapy.

Can high maternal melatonin concentrations be responsible for inducing fetal pathologies, and can melatonin participate in immunohormonal homeostasis by determining prohormone convertase activity?--Hypothesis and facts.

The hypothesis proposed here presents a mechanism of melatonin action, which may explain the role of this neurohormone in the genesis of various human pathologies, including fetal abnormalities. It assumes that monomeric or dimeric forms of indoloderived compounds such as melatonin and precursors of melanin have the ability to selectively stimulate the synthesis of prohormone 1 convertase (PC1) or prohormone 2 convertase (PC2), in proportion to their concentrations in the body. Thus, the mean circadian level of melatonin, by determining the manner and rapidity of proopiomelanocortin (POMC) cleavage, would also determine the mean proopiomelanocortin (POMC) level, maintained in dynamic equilibrium as a result of the simultaneous influence of testosterone, estradiol and cortisol on the intensity of POMC mRNA synthesis. The correlative proportions between the activity of PC1 and PC2 would therefore shape the character of hormonal balance in the organism, and in particular the mean ACTH concentration that determines the level of cyclic adenosine monophosphate (cAMP) concentration in its cells. The hypothesis also suggests that melatonin, by influencing the concentration of ACTH and beta-endorphin and their relative proportion could determine the stimulation or suppression of the immune system, thereby confirming its role as an immunomodulator. A disturbance in the above model of immunohormonal equilibrium, resulting from, for example, decreased pineal efficiency, would lead to stimulation of an alternative mode of achieving homeostasis, i.e. increase in concentration of melanin monomers and dimers, with concomitant high activity of tyrosine kinase and high cyclic guanosine monophosphate (cGMP) concentration in the cells. According to the proposed hypothesis, the risk of bearing a developmentally handicapped child would be highest in a woman with a high circadian secretion of melatonin, i.e. with domination of melatonin dimers and high PC1 activity, a condition which may be additionally aggravated by the exposure of the mother to adverse environmental factors or by immunohormonal disturbances. The hypothetical break-up of maternal melatonin dimers when crossing placenta would be the cause of excessive concentration of melatonin monomers and high PC2 activity in the fetus, and thus it should be the reason for very low levels of vimentin filaments and cAMP concentration in embryonal cells, the latter being directly responsible for inducing fetal pathologies.

Clostridium difficile toxins A and B are cation-dependent UDP-glucose hydrolases with differing catalytic activities.

Toxins A and B of Clostridium difficile are UDP-glucose glucosyltransferases that exert their cellular toxicity primarily through their abilities to monoglucosylate, and thereby inactivate, Rho family small GTPases. Toxin A also hydrolyzes UDP-glucose, although this activity is not well characterized. In this study, we measured the kinetics of UDP-glucose hydrolysis by toxins A and B and found significant differences in the catalytic activities of these two structurally homologous toxins. The toxins displayed similar Michaelis constants (Km) for UDP-glucose, but the maximal velocity (Vmax) of toxin B was approximately 5-fold greater than that of toxin A. Toxins A and B exert their enzymatic actions intracellularly, and, interestingly, we found that each toxin absolutely required K+ for optimal hydrolase activity; Na+ was inactive. The toxins also required certain divalent cations for activity and exhibited a significantly greater Vmax and lower Km in the presence of Mn2+ as compared with Mg2+. We conclude that C. difficile toxins A and B are cation-dependent UDP-glucose hydrolases that differ significantly in their catalytic activities, a finding that may have important implications in understanding their different cytotoxic effects.

Cytogenetic and molecular identification of a de novo direct duplication of the long arm of chromosome 4(q21.3-->q31.3).

We report on a 3-year-old boy with moderate developmental retardation, microcephaly, and malformations of ears, lids, mouth, and thumbs. Cytogenetic analysis demonstrated a direct duplication of chromosome subregion 4(q21.3-->q31.3). Confirmation of this specific rearrangement was performed by fluorescent in situ hybridization (FISH) with a chromosome painting probe and by means of quantitative Southern hybridization with DNA probes localized within the chromosome 4 region presumed to be duplicated.

Development of antisera selective for m4 and m5 muscarinic cholinergic receptors: distribution of m4 and m5 receptors in rat brain.

A portion of the cDNA sequence corresponding to the third intracellular loop of either the m4 or m5 muscarinic cholinergic receptor was ligated into the pRIT23 or pET-3a expression vector, respectively. The expressed fusion proteins were purified and used to develop selective polyclonal antisera to the m4 and m5 muscarinic receptors. These antisera were used in an immunoprecipitation protocol to examine quantitatively the distribution of receptor subtypes in regions of rat brain. The density of m4 receptors in rat brain increased in the caudal to rostral direction. The highest levels of m4 receptors were detected in the striatum (1280 fmol/mg) and olfactory tubercle (750 fmol/mg). Low levels of m5 receptors were detected in several brain regions (< 25 fmol/mg). By combining the previously determined receptor densities for the m1, m2, and m3 receptors and results obtained with the newly developed antisera to m4 and m5 receptors, it was determined that 86-99% of the [3H]quinuclidinyl benzilate binding sites in several brain regions were immunoprecipitated. In addition to measuring receptor densities in rat brain, the immunoprecipitation protocol was used to quantify muscarinic receptor levels in tissues reported to express mRNA encoding the m4 receptor. Thus, although only m4 mRNA has been detected in rabbit lung, NG108-15 cells, and N1E-115 cells, both rabbit lung and NG108-15 cells possess both m2 (rabbit lung, 27%; NG108-15 cells, 31%) and m4 (rabbit lung, 55%; NG108-15, 42%) receptors, whereas N1E-115 cells were found to have both m1 (15%) and m4 (65%) receptors. These antisera will be useful in studies of receptor regulation and in determining alterations in density that may occur after pharmacological or physiological manipulations and in various disease states.

Differential regulation of subtypes m1-m5 of muscarinic receptors in forebrain by chronic atropine administration.

The regulation of individual muscarinic receptor subtypes in rat cerebral cortex/dorsal hippocampus was examined following 14-day administration of the nonselective antagonist atropine. Total muscarinic receptor density increased 24%, from 2196 fmol/mg to 2722 fmol/mg. The nature of this increase was examined using a panel of antisera selective for the m1 to m5 muscarinic receptors. Thus, 97% of all cortical/hippocampal receptors were accounted for by immunoprecipitation. Three subtypes were observed to increase significantly in density: m1 receptor from 824 to 982 fmol/mg (19%, P less than .05); m2 receptor from 476 to 519 fmol/mg (9%, N.S.); m3 receptor from 259 to 438 fmol/mg (69%, P less than .001); m4 receptor from 574 to 638 fmol/mg (11%, P less than .05); and the m5 receptor from 23 to 38 fmol/mg (65%, N.S.). Receptors coupled to the hydrolysis of phosphoinositides (m1, m3, m5) appeared to be preferentially up-regulated (32% over control levels, P less than .001) compared with those coupled to the inhibition of adenylyl cyclase (m2, m4; 10% over control levels, P less than .05). The absolute density of the molecularly defined m1 and m4 receptors, which reportedly possess the highest affinity for pirenzepine (M1), increased 16% (P less than .05), whereas the density of receptors having the lowest affinity for pirenzepine (m2, m3 and m5) increased 31% (P less than .001) with atropine treatment. When the increase in total receptor density was examined with [3H]pirenzepine, the 16% elevation in high-affinity (m1 and m4) sites was not detected.(ABSTRACT TRUNCATED AT 250 WORDS)

The ontogeny of m1-m5 muscarinic receptor subtypes in rat forebrain.

The ontogeny of muscarinic receptor subtypes in rat forebrain has been determined utilizing a panel of antisera recognizing unique epitopes of the m1-m5 receptor proteins. Total receptor density in forebrain, as measured by the non-selective antagonist, [3H]quinuclidinyl benzilate (QNB), was found to increase from 507 fmol/mg in neonates (3.5 days) to 1727 fmol/mg in mature animals (45 days). Adult levels were reached two weeks post-partum. A recently developed precipitation protocol was then used to further characterize receptor ontogeny. Cumulatively, 90% of [3H]QNB labelled muscarinic receptors from adult forebrain were immunoprecipitated with subtype selective antibodies (m1-m5). In 3- to 4-day-old neonates, m1 receptors are expressed at 31% of adult levels, m2 receptors at 32% of adult levels, m3 receptors at 36% of adult levels, and m4 receptors at 20% of adult levels. In mature animals, m1 receptors were equal to 35%, m2 equal to 18%, m3 equal to 11%, and m4 equal to 26%, of total receptors, respectively. Levels of m5 receptors are consistently very low at all ages tested (less than or equal to 1% of total receptor density). Although there were subtle differences in the time courses of development between muscarinic receptor subtypes, in general, they developed with similar ontogenic profiles. Subtypes coupled preferentially to inhibition of adenylate cyclase (m2 and m4) comprised 35% of total receptors expressed in neonates. The combined m2/m4 receptor density increased at a uniform rate during development from 173 to 757 fmol/mg. Receptors preferentially coupled to phosphoinositide turnover (m1, m3, and m5) were found in newborns at approximately 270 fmol/mg.(ABSTRACT TRUNCATED AT 250 WORDS)

[Cytological examination of the amniotic fluid in normal pregnancy and in cases of fetal central nervous system abnormalities]. / Badania cytologiczne plynu owodniowego w ciazy fizjologicznej oraz w przypadkach wad centralnego ukladu nerwowego u plodu.

Cytological and biochemical investigations were carried out on 60 samples of amniotic fluid obtained from 30 pregnant women with risk for development of fetal central nervous abnormality (FCNA) and 30 pregnant women in whom prenatal diagnosis was indicated for other reasons (control group). Cytological evaluation was done in an interference-polarization Nomarski microscope evaluating the cells in direct preparation and after staining with neutral red. Parallelly with cytological evaluation alpha-1-fetoprotein (AFP) and acetylcholinesterase (AChE) were determined in amniotic fluid. In three cases with open neural tube anomaly characteristic cells with strongly puckered and vacuolized cytoplasmic membranes were found. In these cases the levels of AFP and AChE exceeded the normal range. In two cases of closed abnormalities of the central nervous system diagnosed by ultrasonography no abnormalities were note by cytological and biochemical methods. The study confirmed the usefulness of the cytological examination of amniotic fluid, as a method supplementing biochemical and ultrasonographic investigations as part of prenatal diagnosis.

The results of topical application of 13-cis-retinoic acid on basal cell carcinoma. A correlation of the clinical effect with histopathological examination and serum retinol level.

A group of 50 patients with basal cell carcinoma of the face was treated by 13-cis-retinoic acid. The treatment resulted in diminution of the tumors. Complete regression was observed in 4 cases. Histological examination revealed necrosis of cancer cells and mononuclear infiltration into the treated tumors. In the group with weak clinical and histological reaction to the treatment all basal cell carcinomas were of adenoid type. A better effect was observed in the group with lower serum retinol level. This treatment method seems to be supplementary to surgery in prevention of the tumor recurrence.