Hypoxidaceae. Medicinal uses and the norlignan constituents. Glycosides of uncommon aglucones, characterized by the Ph-C5-Ph skeleton, were isolated from the rhizomes of some African Hypoxis species. HPLC analysis indicated the occurrence of these compounds in other Hypoxidaceae. On the basis of structural evidence and biogenetic considerations, the aglucones of these glycosides can be considered as norlignans, derived from the union of two phenylpropanoid units in positions alpha, beta' or beta, gamma' and with the loss of the terminal carbon of a chain. Several Hypoxis species are used in traditional medicine as antiinflammatory and antitumor drugs and, recently, preparations based on lipophilic extracts of H. rooperi have been introduced into the market for the treatment of prostatic hypertrophy.


Effect of opioids on delayed neuronal death in the gerbil hippocampus. The effect of opioids on delayed neuronal death was evaluated in the gerbil hippocampus. Male Mongolian gerbils were subjected to transient forebrain ischemia and neuronal density was evaluated in the hippocampus 7 days following ischemia. When hypothermia during and after ischemia was prevented, treatment with morphine, U-50488H, or naloxone provided no significant protection. In contrast, a spontaneous drop in rectal temperature to 32 degrees C at the end of ischemia produced near-complete protection of CA1 pyramidal neurons. No opioids modulate the protective effect of hypothermia.


The restoration of ATP synthesis may explain the protective effect of calcium antagonists against cyclosporine A nephrotoxicity. Cyclosporine A at pharmacological doses decreases the rate and yield of ATP synthesis in rat mitochondria. This action seems to be due to the mitochondrial calcium storage induced by the drug. If such an effect occurs in vivo, the ATP deficit will affect calcium extrusion pumps, so triggering vasoconstriction which is the major side effect of Cyclosporine A. Calcium antagonists (Nifedipine and Verapamil) at least partially correct this effect on ATP synthesis: this finding may be related with the beneficial clinical effect conferred on Cyclosporine A toxicity by calcium antagonists. This effect of calcium antagonists may be due to an interaction with Cyclosporine A at the level of mitochondrial calcium efflux.


Further characterization of alpha N-acetyl beta-endorphin-(1-31) regulatory activity, I: Effect on opioid- and alpha 2-mediated supraspinal antinociception in mice. Picomol doses of the acetylated derivative of beta-endorphin-(1-31), injected intracerebroventricularly (icv) in mice, reduced the analgesic activity of morphine, etorphine and beta-endorphin-(1-31), while the efficiency of DAGO and DADLE in producing analgesia was enhanced. The effects of the delta agonists DPDPE and [D-Ala2]-Deltorphin II were not altered by this treatment. After alpha N-acetyl beta-endorphin-(1-31) injection, morphine antagonized the analgesia of DAGO. The regulatory effect of alpha N-acetyl beta-endorphin-(1-31) was exhibited when giving the peptide both before (up to 24 h) and after the opioids. Naloxone did not prevent or reverse that modulatory activity; moreover, pretreatment with the acetylated peptide did not change the pA2 value displayed by the antagonist at the mu receptor. The antinociceptive activity of the alpha 2-adrenoceptor agonist clonidine was also increased in mice treated with alpha N-acetyl beta-endorphin-(1-31). The reducing activity of alpha N-acetyl beta-endorphin-(1-31) upon morphine- and beta-endorphin-induced analgesia was not exhibited in mice undergoing treatment with pertussis toxin or N-ethylmaleimide, agents known to impair the function of Gi/Go transducer proteins. However, the enhancing activity displayed by this peptide upon DAGO- DADLE and clonidine-evoked antinociception was still manifested. These results confirm and strengthen the idea of alpha N-acetyl beta-endorphin-(1-31) acting as a non-competitive regulator of mu opioid- and alpha 2-adrenoceptor-mediated supraspinal antinociception. A neural substrate acted on by both receptors (likely Gi/Go transducer proteins) appears to be involved in the effects of that neuropeptide.


Nonmembrane associated dolichol in rat liver. The distribution of dolichol in rat liver was studied. Upon high-speed centrifugation, 9% of the total tissue dolichol was recovered in the supernatant. Dolichol was enclosed in vesicles and in lipidic particles which were isolated by gel filtration and density gradient centrifugation. The particles had a diameter of 20 nm and contained dolichol, ubiquinone, cholesterol, phospholipid and some protein. Similar particles were recovered upon incubation of isolated hepatocytes with liposomes containing dolichol. From the lysosomal lumen, lipid particles containing dolichol, ubiquinone, cholesterol and phospholipid, but no protein, were isolated. The diameter of the particles was 20-40 nm with a molecular weight of 130 kDa. Puromycin treatment inhibited protein synthesis, but did not affect dolichol transfer from the endoplasmic reticulum to lysosomes, suggesting that the transfer is not mediated by newly synthesized apoprotein. The results indicate that a sizeable portion of the total cellular dolichol is present in cytoplasm and in lysosomal lumen. Furthermore, dolichol probably participates in the translocation process.


Gamma linolenic acid (GLA) content of encapsulated evening primrose oil products. The fatty acid composition of 16 brands of evening primrose oil (EPO) capsules was determined by capillary gas chromatography. Fourteen of these EPO brands contained gamma-linolenic acid (GLA) levels between 7% and 10% (mean, 8.7; range, 1.9-10.5%) and there was generally good agreement between the level of GLA claimed by the manufacturer and the level determined by analysis. Low levels of the monoenes 22:1 and 24:1 found in some brands may indicate contamination of EPO with borage oil.


Capillary as a communicating medium in the microvasculature. The preceding study (Dietrich and Tyml, 1992. Microvasc. Res. 43) demonstrated that a local application of norepinephrine (NE) on a capillary in a skeletal muscle produces a temporary reduction in blood flow within this capillary. The reduction is mediated via constriction of the supplying arteriole. The objective of the present study was to address the mechanism by which the local NE stimulus is propagated from the capillary to the arteriole. Using intravital video microscopy we measured red blood cell velocity in capillaries, and diameter of supplying arterioles, in the sartorius muscle in anesthetized frogs. Velocity responses were measured following iontophoretic application of NE (3 mM in the pipette) on the capillary, with or without pretreatment with 0.9 mM tetrodotoxin (nerve-specific sodium channel blocker), 30 mM lidocaine (nonspecific sodium channel blocker), and 30 mM yohimbine (alpha 2-receptor blocker). Diameter responses were measured before and after capillary damage introduced by microcautery. Tetrodotoxin did not block the NE-induced velocity reduction (i.e., from 0.2 to 0.07 mm/sec), while lidocaine attenuated it. Yohimbine blocked it only when applied on the same site as NE. Capillary damage abolished the NE-induced arteriolar constriction (i.e., from 27.8 to 21.5 microns). We conclude that the observed responses were not due to (1) direct diffusion of NE from the capillary to the arteriole, (2) conduction along adrenergic nerves, or (3) venous-arteriolar diffusional cross-talk. We interpret our data to indicate that the capillary itself could function as a communicating medium.


Genetics and epidemiology of Wilms' tumor: the French Wilms' tumor study. A complete family history was obtained for 501 patients with Wilms' tumor, treated in departments of pediatric oncology in whole France. The information was collected by self-questionnaire and/or by interview of parents. The proportion of bilateral cases is 4.6% and there are 12 patients (2.4%) with a positive family history of Wilms' tumor. The affected relatives are most often distant and no first degree relative was affected. Apart from the well-known associations with aniridia, hemihypertrophy, genitourinary anomalies, Beckwith-Wiedeemann, and Drash syndromes, there is also a significant excess of congenital heart defects (P = .008) which remains to be explained. Several findings support the bimutational hypothesis such as earlier diagnosis and increased parental age in bilateral cases. No particular anomalies and no increased frequency of childhood cancer were found in patients' relatives. The frequency of Wilms' tumor in relatives was estimated to be less than 0.4% in sibs, 0.06% in uncles and aunts, and 0.04% in first cousins. These figures are very different from those found in retinoblastoma and suggest that the mechanism may be more complex in Wilms' tumor. This conclusion is in agreement with molecular biology studies in tumors and linkage analysis in multiple case families which suggest that more than one locus is involved.


Causes of death in a paediatric oncology unit. The records of 101 patients (64 males and 37 females) registered at Bristol Children's Hospital who died between January 1986 and December 1989 were reviewed to determine the cause of death. Nineteen patients (19%) died without obtaining remission and 6 (6%) in first remission. Seventy-six (75%) died after relapse; three during re-induction and two in second remission. The causes of death were active disease in 85 patients (84%), active disease and infection (4%), active disease and other factors (4%), infection only (3%), toxic cardiomyopathy (2%), graft versus host disease (2%), and second malignancy (1%).


Analysis of an immunodominant epitope of topoisomerase I in patients with systemic sclerosis. In this paper an immunodominant epitope of Topoisomerase I is described. An epitope expression sublibrary was constructed from Topoisomerase I cDNA. The subclones were screened with an antiserum from a patient with systemic sclerosis (SSc). The positive clones defined one immunodominant B cell epitope (epitope III), which was located at the carboxyterminal part of the protein. The epitope, 52 amino acids in length, neither contains the p30gag sequence nor the suggested active site Tyr-723, both presumed antibody recognition sites. More than 70% of our anti-TopoI sera recognize this epitope III, indicating that it is a major recognition site of the anti-TopoI autoantibodies in SSc sera. DNA relaxation experiments show that all sera that recognize epitope III and most sera with antibodies to other epitopes inhibit Topoisomerase I activity.


Specific regulatory role of phosphorylation of calf thymus DNA-topoisomerase I smaller forms on the relaxational activity expression. Phosphorylation role on Topo I smaller forms activity. Calf thymus Topo I is found to be associated with three active breakdown products, resolved from intact enzyme, which do not appear to be unique to one extraction procedure. They are phosphoproteins, whose enzymatic activity can be modulated through changes in phosphorylation, and which can be phosphorylated 'in vitro', by N II protein kinase, in the same five sites as the intact enzyme. Different amounts of 32P incorporated are observed however, in the corresponding sites. We conclude: 1. proteolysis is probably an 'in vivo' phenomenon, as the Topo I smaller species are observed, during isolation from the earlier crude fractions, and as a minimum of them is always present, even if precautions are taken to minimize proteolysis; 2. a specific regulatory role in the DNA relaxational activity might be played by N II protein kinase phosphorylation, indeed, in the smaller species; 3. the different degrees of 32P incorporation, in analogous phosphorylation sites, might represent a different signal for modulating the gene expression.


Detection of functional ovarian hyperandrogenism in women with androgen excess. Distinguishing between ovarian and adrenal causes of androgen excess may be difficult. We have found that women with the polycystic ovary syndrome have supranormal plasma 17-hydroxyprogesterone responses to the gonadotropin-releasing hormone agonist nafarelin. We determined the usefulness of testing with nafarelin to distinguish ovarian causes of hyperandrogenism in women. We studied 40 consecutive women with hyperandrogenism who had oligomenorrhea, hirsutism, or acne. All 40 underwent testing with nafarelin, dexamethasone, and corticotropin with measurement of circulating concentrations of gonadotropins and steroid hormones, and 19 underwent ovarian ultrasonography. The plasma 17-hydroxyprogesterone response to nafarelin was supranormal in 23 of the 40 women (58 percent), and the plasma androgen response to corticotropin was elevated in 23; 13 women had both abnormalities. Only one woman had conclusive evidence of a steroidogenic block; she had nonclassic adrenal 21-hydroxylase deficiency. Of the 23 women with abnormal responses to nafarelin, only 11 (48 percent) had elevated base-line serum luteinizing hormone concentrations. Of the 13 women with abnormal responses to nafarelin who underwent ultrasonography, 7 (54 percent) had polycystic ovaries. Peak plasma 17-hydroxyprogesterone concentrations after nafarelin administration correlated closely with plasma free testosterone concentrations after dexamethasone administration (r = 0.75, P less than 0.001). Approximately half of women with oligomenorrhea, hirsutism, or acne have an abnormal response to the gonadotropin-releasing hormone agonist nafarelin, suggesting an ovarian cause of their androgen excess.


Progesterone promotes rapid desensitization of alpha 1-adrenergic receptor augmentation of cAMP formation in rat hypothalamic slices. We previously demonstrated that norepinephrine (NE) induction of cAMP accumulation in slices of the preoptic area (POA) and middle hypothalamus (MH) is reduced by in vivo administration of progesterone to estradiol-primed rats, apparently by eliminating alpha 1-receptor augmentation of beta-receptor-stimulated cAMP formation. The present studies examined whether in vitro exposure to progesterone would also depress NE-stimulated cAMP synthesis. POA and MH slices from estradiol-primed females were incubated with 20 nM progesterone for 5-30 min prior to addition of 100 microM NE. Pre-incubation of slices with progesterone for as little as 5 min significantly suppressed NE-stimulated cAMP formation by greater than 60%. This effect was estrogen-dependent in that progesterone in vitro did not inhibit NE-stimulated cAMP accumulation in slices from ovariectomized rats not pretreated with estradiol. Isoproterenol, a beta-adrenergic agonist, elevated cAMP to the same extent in slices from estradiol-primed females incubated with and without progesterone in vitro; however, the alpha 1-agonist, phenylephrine, was unable to augment cAMP formation in slices incubated in vitro with progesterone for 5 min prior to drug challenge. To determine whether the rapid effects of progesterone may be exerted at the level of the plasma membrane, we employed progesterone conjugated to bovine serum albumin at carbon 3 (P-3-BSA). Slices from estradiol-primed rats incubated with P-3-BSA for 5 min did not exhibit an alpha 1-receptor augmentation of beta-receptor-stimulated cAMP accumulation. These data indicate that progesterone may have rapid, non-genomic effects on alpha 1-adrenergic receptor coupling to second-messenger systems in the hypothalamus of female rats.


Effects of thymosin alpha-1 on pituitary hormone release. The thymosins are a family of hormone-like products of epithelial cells of the thymus which are important in maintenance and function of the immune system. Thymosin fraction 5, a partially purified extract of calf thymus, can influence pituitary hormone release. We have studied the effects of thymosin alpha 1 (T alpha 1), the first peptide isolated from thymosin fraction 5, on thyrotropin (TSH), adrenocorticotropin (ACTH), prolactin (Prl) and growth hormone (GH) release. To evaluate its effect in vivo we injected the peptide into the third ventricle of conscious male rats and measured the concentration of the pituitary hormones in plasma at different times after the injection. Following third-ventricular injection of T alpha 1, there was a significant decrease in plasma TSH and ACTH concentrations in comparison with values of control groups injected with diluent. The decrease in plasma TSH was of longer duration and was obtained with a lower dose of T alpha 1 than that of ACTH. Also, a significant decrease in plasma Prl was observed, with the same dose as for TSH. On the other hand, there were no significant changes in plasma GH. To examine if there is any direct effect of T alpha 1 at the pituitary level, we incubated hemipituitaries from male rats in vitro with different concentrations of the peptide. In this system T alpha 1 evoked a dose-dependent release of TSH and ACTH, while there was no effect on the release of Prl and GH.(ABSTRACT TRUNCATED AT 250 WORDS)


Restraining action of GABA on estradiol-induced LH surge in the rat: GABA activity in brain nuclei and effects of GABA mimetics in the medial preoptic nucleus. The relationship between GABA dynamics and LH release was studied on day 2 after subcutaneous estrogen implant in short-term ovariectomized rats. GABA accumulation, used as an index of GABA turnover, was determined in the medial preoptic nucleus (MPN), medial (MS) and lateral (LS) septal nuclei, median eminence-mediobasal hypothalamus (MBH) and locus ceruleus (LC). Measurements of GABA were performed at two different times of day (11.00 and 15.00 h), 3 h after intraperitoneal administration of gamma-vinyl-GABA (GVG), an irreversible inhibitor of GABA transaminase. Either morning or afternoon ovariectomized rats (OVX) showed a significant increase in GABA accumulation after GVG treatment in all the areas studied. Estrogen-treated OVX rats showed in the morning a lower GABA accumulation in the MPN, MBH and LC, and GABA levels remained unchanged in the LS and MS. In the afternoon, the MPN and LS showed a lower rate of GABA accumulation whereas in the MBH and LC the GABA increase was not observed. In contrast the MS showed a rate of GABA accumulation similar as in the OVX rats. Local administration in the MPN of 20 micrograms GVG, or GABA-A receptor stimulation by muscimol (50 ng), prior to the increase in plasma LH levels, prevented the occurrence of the estradiol-induced LH surge. The effect of muscimol was reversed by bicuculline (30 ng), a GABA-A receptor antagonist. Bicuculline in low doses lacked effect by itself. In conclusion, these results strongly suggest that a decreased GABAergic activity in MPN, MBH and LC precedes the estradiol-evoked LH surges in ovariectomized rats. Moreover, that in septal nuclei, a low GABAergic activity takes place well before the occurrence of plasma LH increase.(ABSTRACT TRUNCATED AT 250 WORDS)


Distribution of benzodiazepine binding sites in the brain of the male Japanese quail and its correlation to a hormonal control: quantitative autoradiography study. Quantitative receptor autoradiography was used to study the neuroanatomical distribution and effects of gonadal hormones on [3H] flunitrazepam binding in the male Japanese quail brain. In gonadally intact quail brains, [3H] flunitrazepam displayed a heterogeneous distribution, with elevated levels in the posterior brain regions such as the stratum griseum et fibrosum superficiale and stratum griseum centrale of the optic tectum. Lower values were observed in the anteriorly located brain sites such as the nucleus septalis (lateralis et medialis), the cortex dorsolateralis and the nucleus lateralis hypothalami. Castration affected [3H] flunitrazepam binding levels in brain areas known to contain gonadal steroid receptors as well as in some areas which were devoid of gonadal steroid receptors. Castration in fact, elevated [3H] flunitrazepam binding in the nucleus preopticus anterior and reduced binding levels in archistriatum dorsalis et ventralis and in the nucleus intercollicularis; all of these areas are known to have gonadal steroid receptors. In two regions which do not contain such receptors, namely the hyperstriatum ventrale and the cerebellum pars granularis, castration increased [3H] flunitrazepam binding. In order to determine whether the gonadal steroid effect is due to changes either in the number of binding sites (Bmax) and or affinity binding state (KD), saturation binding studies were carried out in some of the areas described above in brains of quail which were castrated or castrated and given replacement therapy with testosterone or estradiol for 2 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)


Dynamic patterns of medial preoptic mu-opiate receptor regulation by gonadal steroid hormones. The density of mu-opiate receptors located in the medial preoptic area (MPOA) of the rat hypothalamus is cyclical and sexually dimorphic. The hormonal regulation of MPOA mu-receptors was examined in ovariectomized rats treated with a variety of hormone regimens. In experiment 1, animals received acute estradiol (E2), progesterone (P), or prolactin (PRL), or E2 followed in 48 h by either P or vehicle by subcutaneous injection. Brains were removed 3 h after the final injection. In experiment 2, animals were implanted with empty or E2-filled Silastic capsules, and received either P or vehicle by injection 48 h later, at which time E2 capsules were removed. One group received E2 implants which remained in place following sham removal surgery. Brains and trunk blood for radioimmunoassay of E2 and P were collected 3, 27 or 51 h after the final injection. Frozen brain sections were prepared, incubated in [3H]D-Ala2,MePhe4,Gly-ol5-enkephalin, which selectively labels mu-receptors, and analyzed using quantitative receptor autoradiography. P treatment significantly increased MPOA mu-receptors, but only 27 h after E2 priming. Neither shorter P exposure, nor E2, P or PRL alone affected MPOA mu-receptor density. Following this delayed E2,P-induced increase, mu-receptor density subsequently decreased in the presence of absence of E2. The results suggest that E2,P treatment produces a gradual and transient increase of MPOA mu-receptor density. The subsequent decrease of receptor density is independent of the presence of E2 and may be related to receptor turnover. The time course of this effect is consistent with that of the estrus cycle. Such hormone-induced regulation of MPOA mu-receptor density could influence the physiologic effects of opiates on gonadotropin secretion and reproductive behavior in cycling females.


Effects of cocaine and pimozide on plasma and brain alpha-melanocyte-stimulating hormone levels in rats. The effects of cocaine on rat plasma and brain alpha-melanocyte-stimulating hormone (alpha-MSH) levels have been studied by means of a specific radioimmunoassay. The selected brain areas were the hypothalamus, septum-nucleus accumbens and hippocampus. Cocaine given subcutaneously decreased the alpha-MSH levels in the peripheral blood. Pimozide, a dopaminergic antagonist, had an opposite effect: it increased the alpha-MSH levels in the peripheral blood. Combined treatment with cocaine + pimozide resulted in a decrease in the pimozide-induced increase in alpha-MSH levels in the blood. Cocaine and pimozide or the combination of cocaine + pimozide were ineffective on the alpha-MSH levels in the hypothalamus and septum-accumbens brain regions. In the hippocampus, cocaine in the dose applied induced a slight but not significant decrease in the alpha-MSH level. Pimozide caused a significant decrease in the hippocampal alpha-MSH level which disappeared at 60 min. Cocaine prevented the pimozide-induced depletion of alpha-MSH. The data indicate that cocaine may act as a dopaminergic agonist in the mechanism of control of alpha-MSH secretion from the intermediate lobe of the pituitary. The alpha-MSH levels in the brain are controlled by different mechanisms. In some brain areas, the dopaminergic system has no action; in others the mechanisms might be similar to but slightly different from that in the pituitary.


Diurnal corticotropin-releasing hormone mRNA variation in the hypothalamus exhibits a rhythm distinct from that of plasma corticosterone. The hypothalamopituitary-adrenal axis exhibits a diurnal rhythm as witnessed by the daily excursion of corticosterone in plasma. The rhythm appears to be mediated largely by the stimulation of CRH neurons in the paraventricular nucleus (PVN) of the hypothalamus. In the present study, we investigated the effects of circadian influence on CRH mRNA levels in the paraventricular hypothalamus. Animals were sacrificed through a 24-hour period to establish a detailed time course of CRH mRNA fluctuations. Levels of both type I and type II corticosterone receptor mRNAs were also measured in this area to see whether changes correlate with that of CRH mRNA. Plasma levels of ACTH were quantified as an index for CRH peptide secretion. The results indicate that changes in ACTH closely paralleled alterations in corticosterone levels with an increasing trend starting at 1 PM, suggesting that the diurnal secretory drive commences around this time. The CRH mRNA rhythm as determined by RNase protection assays appeared to change in an anticipatory fashion to these endocrine fluctuations, increasing during the light phase and reaching maximal levels just prior to dark (5-6 PM). An abrupt decrease of 30% in the CRH mRNA content was detected in the hypothalamus within 2 h after dark (8 PM) and coincided with the peak of plasma corticosterone levels. However, other periodic variations in the CRH mRNA content were not accompanied by changes in plasma corticosterone. Neither types of corticosterone receptor mRNAs showed any diurnal change suggesting that the expression of steroid receptors in the hypothalamus is not regulated by circadian influences. We conclude that CRH mRNA levels fluctuate diurnally but are inversely related to corticosterone levels only in the early evening.


Pulsatile ACTH and cortisol in goats: effects of insulin-induced hypoglycemia and dexamethasone. Insulin-induced hypoglycemia is a metabolic stress that stimulates secretion of adrenocorticotropic hormone (ACTH) and cortisol in a number of animal species. Dexamethasone is a potent synthetic glucocorticoid that suppresses the secretion of ACTH and cortisol. Both ACTH and cortisol exhibit complex secretory patterns demonstrating ultradian and circadian rhythms. This work investigated the pattern of ACTH and cortisol response to hypoglycemia in goats and the effect of dexamethasone on this response. Five goats were pretreated with dexamethasone (0.1 mg/kg) and 5 with saline. Blood samples were taken every 2 min for 60 min before and 60 min after administration of insulin (2.5 IU/kg, i.v.). Immunoreactive ACTH and cortisol were measured in all samples and glucose in selected samples. Data sets were analyzed for significant pulses with the Cluster Analysis program. Complete data sets were compared as well as those for each 30-min interval. Plasma glucose was lower than preinsulin levels at 10 min, declined rapidly between 10 and 30 min, and remained low 30-60 min after insulin injection in both treatment groups. Controls showed a rapid rise in ACTH and cortisol beginning 30 +/- 10 min postinsulin. The increase in mean plasma hormone levels during hypoglycemia was predominantly due to an increase in amplitude of secretory pulses for ACTH and cortisol compared with the 30 min before insulin. Dexamethasone significantly lowered mean ACTH and cortisol levels and prevented alteration in plasma ACTH and cortisol secretion during hypoglycemia but did not totally ablate pulsatile activity of either hormone. The amplitude of ACTH and cortisol pulses was significantly decreased by dexamethasone treatment. The frequency of cortisol but not ACTH pulses was also significantly decreased.(ABSTRACT TRUNCATED AT 250 WORDS)


[Viral and/or intraepithelial lesions of the lower female genital tract: diagnostic and prognostic value of in situ molecular hybridization]. Fourteen patients (mean age 37 years) suffering from viral and/or intraepithelial cervico-vagino-vulvar pathologies underwent colposcopic and cyto-histological tests and molecular hybridization. The following types of HPV were assayed: 6/11-16/18-31/35/51 in cytological tissues (exocervical scraping) and biopsy material immersed in paraffin and fixed in formalin buffered with 10% PBS. The aim of the study was to identify different types of HPV using molecular hybridisation in situ. The paper reports the results and correlations with colposcopic, cytological and histological diagnosis, and then discuss the clinico-biological and prognostic aspects of this method.


Voltage-dependent modulation of calcium current by GTP gamma S and dopamine in cultured frog pituitary melanotrophs. Dopamine (1 microM) reversibly scaled down barium current through high-voltage activated (HVA) calcium channels but had little effect on the time course of current activation in cultured frog melanotrophs. Intracellular perfusion with guanosine-5'-O-(3-thiotriphosphate) (GTP gamma S; 100 microM) sustained the effect of dopamine. Moreover, GTP gamma S drastically slowed down the current activation kinetics. The latter effect was in part reversed by dopamine. A conditioning prepulse to +70 mV facilitated the current in GTP gamma S-dialyzed cells but not in cells exposed to dopamine. These results suggest the existence of a dual G protein-mediated mechanism for reducing HVA calcium current.


Spontaneous discharge originates in the dorsal root ganglion at the onset of a painful peripheral neuropathy in the rat. The activity of myelinated primary afferents was recorded from the dorsal roots 1-3 days after creation of a painful peripheral neuropathy in rats. The effects on spontaneous discharge of acute transections at various points along the injured sciatic nerve and the dorsal root were determined, as were the effects of K+ channel blockers applied topically to two putative sites of impulse origin: the injured region of the nerve and the dorsal root ganglion (DRG). Transections just proximal to the nerve injury and just distal to the DRG failed to halt the discharge, but spontaneous discharge disappeared when the transection was made just proximal to the DRG (i.e. between the DRG and recording electrode). K+ channel blockers (4-aminopyridine and gallamine triethiodide) applied to the DRG increased the frequency of spontaneous discharge or initiated activity from silent fibers. Applications of K+ channel blockers to the injured region of the nerve were without effect. Thus, the spontaneous discharge and the sensitivity to K+ channel blockade seen in A beta and A delta primary afferents at the time of the onset of the neuropathic pain syndrome appear to originate in the DRG.


Presynaptic facilitation of excitatory postsynaptic potential by glucagon in neurons of rat ventromedial hypothalamic slices. Intracellular recordings were made from neurons in rat ventromedial hypothalamus (VMH), in vitro. Application of glucagon (100 nM to 5 microM) for 2-5 min increased the amplitude of excitatory postsynaptic potential (EPSP) lasting for 10-20 min. Forskolin and 8-bromo-cyclic AMP mimicked glucagon in producing a long-lasting facilitation of the EPSP. These drugs did not affect depolarizing response produced by glutamate. 3-Isobutyl-1-methylxanthine (IBMX) potentiated the time course of glucagon-induced facilitation of the EPSP. These results suggest that glucagon facilitates the EPSP probably by increasing transmitter release through activation of adenylate cyclase.


Thapsigargin blocks the induction of long-term potentiation in rat hippocampal slices. Experiments were performed to investigate whether intact intracellular Ca2+ pools are necessary for long-term potentiation (LTP) in the CA1 region of rat hippocampal slices. Thapsigargin (1 microM), which depletes most intracellular Ca2+ pools by blocking ATP-dependent Ca2+ uptake into intracellular compartments, blocked the induction but not the expression of LTP. Thapsigargin had no effect on synaptic transmission or on responses mediated by N-methyl-D-aspartate (NMDA) receptor activation. These data suggest that Ca2+ release from intracellular stores is required for the induction of LTP.


Hypothermic effect of D-Ala-deltorphin II, a selective delta opioid receptor agonist. The natural heptapeptide D-Ala-deltorphin II, the most selective agonist for delta-receptors currently available, was used to study the role of brain delta opioid receptors in the control of body temperature. In rats placed in a cold ambient temperature (4 degrees C), intracerebroventricular injections of D-Ala-deltorphin II produced a significant hypothermia. In animals at an ambient temperature of 22 degrees C, only the highest dose employed induced a slight fall in body temperature. At a warm temperature (34 degrees C), D-Ala-deltorphin II induced no significant changes in body temperature. D-Ala-deltorphin II-induced hypothermia, unaffected by naloxone, was significantly reduced by the selective delta receptor antagonist naltrindole. These findings indicate that D-Ala-deltorphin II produces its hypothermic effects at a supraspinal delta receptor, and support the involvement of delta receptors in central control of body temperature.


Distinct regulation of vasoactive intestinal peptide (VIP) expression at mRNA and peptide levels in human neuroblastoma cells. Neuronal differentiation was induced in cultures of the human neuroblastoma cell line subclone SH-SY5Y by 14-day treatment with dibutyryl cAMP (dBcAMP), retinoic acid, and phorbol 12-myristate 13-acetate (PMA). An approximate 4-fold increase in vasoactive intestinal peptide (VIP) mRNA concentration was observed after differentiation with retinoic acid, whereas no change in VIP mRNA concentration was observed after differentiation with dBcAMP or PMA. A short-term treatment of cells with PMA did however result in a 5-fold transient increase in VIP mRNA; prior differentiation with retinoic acid or dBcAMP diminished this effect. Observed increases in VIP mRNA were in all cases accompanied by increases in VIP immunoreactivity. Remarkably, however, long-term treatment of cells with dBcAMP, which caused no change in mRNA levels, resulted in a six-fold increase in VIP immunoreactivity. Acute (36-h) treatment with carbachol also caused an increase in VIP immunoreactivity (about 2-fold, and blocked by atropine) without an increase in VIP mRNA level. Thus, a quantitative change in gene transcription or mRNA stability appears not to be a prerequisite for increased VIP expression, indicating that regulation can occur at translational or post-translational steps.


NK-1, but not NK-2, tachykinin receptors mediate plasma extravasation induced by antidromic C-fiber stimulation in rat hindpaw: demonstrated with the NK-1 antagonist CP-96,345 and the NK-2 antagonist Men 10207. The effects of intradermal injection of CP-96,345 and Men 10207, selective antagonists for NK-1 and NK-2 tachykinin receptors, respectively, on the extravasation of plasma protein induced by antidromic stimulation of unmyelinated sensory fibers in the sciatic nerve was studied in rat hindpaw. Activation of unmyelinated fibers by antidromic sciatic nerve stimulation (1 Hz, 5 min) consistently evoked a localized plasma extravasation of Evans blue on the skin area of the hindpaw innervated by the sciatic nerve, which was not inhibited by intradermal injection of saline or Men 10207 (9 and 35 nmol). In contrast, CP-96,345 (3 and 9 nmol, but not 1 nmol), injected intradermally 15 min prior to nerve stimulation dose-dependently inhibited this response. Plasma extravasation induced by intravenously injected substance P was also inhibited by CP-96,345. Since CP-96,345 is a highly selective antagonist for NK-1 tachykinin receptors, it is suggested that the plasma extravasation induced by antidromic C-fiber stimulation and by systemically applied tachykinins is mediated by NK-1 tachykinin receptors.


The mechanism of GABAB-mediated slowing of the activation phase of high voltage-activated Ca2+ channels in rat sensory neurons. The mechanism underlying the slowed activation of the high voltage-activated Ca2+ current (HVA-ICa) in the presence of (-)-baclofen was studied in cultured neurons of rat dorsal root ganglia. The decay phase of the baclofen-sensitive component of HVA-ICa was described by a sum of two exponential functions. Although the inhibited portion in the amplitude of the baclofen-sensitive component of HVA-ICa was increased in a concentration-dependent manner, the two decay time constants remained unaffected regardless of the concentration of baclofen. Furthermore, the baclofen-sensitive component of HVA-ICa was largely inactivated by a depolarizing prepulse (-30 mV for 0.5 s). These results support the notion that the slowed activation of the HVA-ICa in the presence of baclofen is due to a preferential inhibition of the inactivating component of HVA-ICa rather than due to voltage-dependent unblocking of a single population of HVA-ICa.


DNA fragmentation in focal cortical freeze injury of rats. This study examined the appearance of double-strand DNA breaks in rat brain after a focal cortical freeze injury in vivo. DNA fragments of oligonucleosome size appeared 3 h after the injury, and increased in a time-dependent manner. At 24 h, the amount of DNA fragmentation reached a maximum and then declined. When nuclei from freeze-injured brain tissue were incubated with Ca2+ in vitro, increased endonuclease activity, which can cause DNA fragmentation, was found. These findings indicate that the activation of a Ca(2+)-dependent endonuclease may be involved in the evolution of freeze-traumatized brain tissue.


Neurohypophysial responses to emotional stress after deafferentation of sino-aortic baroreceptors in rats. In an attempt to test the possibility that sino-aortic baroreceptors may mediate the previously reported stress response in hypothalamic magnocellular neurosecretory cell activity in rats, effects of deafferentation of sino-aortic baroreceptors on plasma levels of vasopressin and oxytocin after fear-related emotional stress were studied in male rats 28-33 days after the surgery. An alpha 1-adrenergic receptor agonist, phenylephrine (1 mg/kg) injected i.p. under anesthesia increased arterial blood pressure in the rats that had received surgical operation of sino-aortic denervation (SAD) and in the rats of sham-operation control (SHAM). Reflex bradycardia after phenylephrine occurred in the SHAM but not in the SAD group. These results indicate that afferent signals originating from sino-aortic baroreceptors were effectively blocked by the SAD surgery. In the similarly prepared SAD group, plasma level of vasopressin was decreased and plasma level of oxytocin was increased significantly to the same extent as in the SHAM group after low-frequency shocks (0.05 Hz, 5 min) or environmental cue signals previously paired with shocks. It is therefore suggested that afferent neural signals originating from sino-aortic baroreceptors are not primarily involved in the suppressive vasopressin or the facilitatory oxytocin response to fear-related emotional stress in rats.


Hyperammonemia induces transient GFAP immunoreactivity changes in goldfish spinal cord (Carassius auratus L.). In this study we have demonstrated that high ammonia concentration in tank water induces changes in the glial fibrillary acidic protein (GFAP) of ependymal cells and radial astrocytes in the goldfish spinal cord. Hyperammonemia was induced by elevating the ammonia concentration in the tank water to 0.88 mM using ammonium chloride; ammonia in control water was less than 0.1 mM. Immunohistochemical methods were used for GFAP and vimentin, and levels were measured at 4, 8, 16, 30, 60, 90 and 120 days. GFAP quantification was made by means of a digital analysis system. The GFAP immunoreactivity was significantly lower at 30 and 60 days of treatment and at 90 days it had returned to control levels. However, no changes in vimentin immunoreactivity were appreciated in any case. GFAP loss was general and was not selective in any specific spinal cord region. To explain this transient generalized loss of GFAP and its posterior recuperation, a possible relation between glutamine synthetase distribution and GFAP changes is discussed.


[Ultraviolet A radiation and the skin. Implications of activated forms of oxygen. Current trends and newest results]. Involvement of activated oxygen species in the responses of skin to solar ultraviolet radiations, especially ultraviolet A radiations, is being addressed by an increasing number of studies. The aim of this review is to outline the concept of "photooxidative stress". The various activated oxygen species, mechanisms involved in their formation, potential cellular targets, and cell defense mechanisms are discussed. Recently published findings are briefly described to illustrate this fast developing line of research.


[Malpighian epithelia and papillomavirus infections]. Human papillomaviruses (HPV) are a large group of DNA viruses, with over 60 types identified to date, which can cause the development of benign tumors in the skin and mucosal squamous epithelia. Most of these tumors regress spontaneously but some, especially in the mucosal membranes, become malignant. HPV types with a high risk for inducing malignancies (e.g. 16 and 18) are the subject of increasing interest. HPVs are both host-specific and tissue-specific: some types preferentially infect specific epithelia, giving rise to lesions with distinct topographic characteristics. HPVs are difficult to study because they do not replicate in available in vitro models. In vivo, HPVs replicate well in epithelial cells undergoing terminal differentiation, e.g. in keratinized cells. Some 40 different types have been reported in epidermal keratinocytes, the most common being types 1 and 2 which produce large amounts of viral antigens and viral particles. In contrast, HPVs replicate poorly in the weakly keratinized squamous epithelia which line the digestive, respiratory, and genital tracts. Junctional epithelia, e.g. on the uterine cervix, are especially prone to HPV infection. The most prevalent HPV types in benign genital lesions are types 6 and 11, whose characteristic features include extrachromosomal DNA and production of only small amounts of viral antigens. The profound nuclear and cytoplasmic changes induced by HPVs lead to the formation of koïlocytes which are found mainly in the granular layer of epithelia and have been especially well described in the uterine cervix and vagina. HPV epithelial tumors are squamous cell carcinomas that often harbor HPV types 16 and 18; this is especially true of cervical intraepithelial neoplasias.(ABSTRACT TRUNCATED AT 250 WORDS)


[Gene transfer and gene therapy].

[Gene transfer and gene therapy]. The application of gene transfer technology to human gene therapy has been intensively investigated during the last decade. The first human clinical trials in adenosine deaminase deficiency and metastatic melanoma recently demonstrated the feasibility and safety of using retroviral gene transduction for human gene therapy. Many problems remain to be solved for a better understanding of the functioning of genes to be transferred, a better efficiency of gene transfer and genetic correction by site-specific targeting in vivo, a better knowledge of the biological properties of target cells such as totipotent hematopoïetic stem cells. Clinical developments are expected in genetic diseases (immunodeficiency, thalassemia, hemophilia) and non genetic disorders (lymphokine gene therapy for cancer).


[Post-traumatic lung pneumatocele. A case in an infant]. Traumatic lung pseudocyst is a lung injury due to closed chest trauma. The authors report one case in a 20 month-old boy. This cavitary lesion is underestimated since associated lesions often mask the pneumatocele. Its frequency is higher in children and young adults. Diagnosis can be assessed early when chest film shows the characteristic cavitary lesion. Computed tomography may be helpful in the recognition of paramediastinal traumatic lung pseudocyst. Since the lung pseudocyst usually involves, no aggressive therapy is justified.


[Diffuse alveolar pertussis with major hyperleukocytosis with "pseudocentrocytic" contingent]. A 21 month-old unvaccinated boy was admitted for an acute respiratory distress episode associated with major leukocytosis (maximum = 146 G/l). Transient heart failure and pneumomediastinum occurred but the outcome was favourable. Coughing attacks then occurred and the diagnosis of pertussis was serologically confirmed. This case report is reminiscent of the possible severity of pertussis pneumoniae, the mechanisms of haematologic abnormalities, and stresses to the benefit of pertussis vaccination.


[Congenital diaphragmatic hernia. Value of preoperative stabilization]. Seventy-two patients with congenital diaphragmatic hernia (CDH) diagnosed in the first 12 hours of live have been reviewed retrospectively. Forty-eight patients born before 1985 (group I) were compared to 24 patients born between 1985 and 1989 (group II). The management was different for the 2 groups. Group I was operated on immediately. For group II, delayed surgery after stabilization was preferred. For this group, stability was sought before, during and after surgery. Therapy was first aimed at optimizing ventilation and oxygenation by way mechanical ventilation. Pharmacologic agents were used in an attempt to decrease pulmonary vascular resistance and improve cardiac output. The survival rate was 37.5% before 1985, 62.5% after 1985 (P less than 0.01). Main prognostic factors were Apgar score, paCO2, pH, ventilation index, alveolar-arterial difference in oxygen and oxygenation index. The stabilization before surgery improved the survival rate.


[Epidemiology of cleft palate and cleft lip inthe Rhône-Alpes/Auvergne/Jura region. Apropos of 903 cases registered 1978-1987]. Data from the Rhône-Alpes/Auvergne birth defects registry have been used to realise an epidemiological analysis of facial clefts (cleft palate and total cleft lip). Between 1978 and 1987, 903 cases have been ascertained giving an incidence of 0.67 per 1,000 for cleft lips with/without cleft palate (CLP) and 0.44 per 1,000 for cleft palates (CP). Several epidemiological characteristics have been studied: CLP are more frequent in males, and CP are more frequent in females. There is no detectable time trend, and birthweights are significantly lower in affected children than in the general population. There are more twins, more maternal epilepsy and more stimulations of ovulation in the studied sample than in the general population. The ranks of birth are higher in CP and CLP than in general population. The incidence of facial clefts in first degree relatives is 50 to 60 times the one in the general population, which is comparable to the literature findings.


[Short-duration fatty meal loading for the assessment of intestinal malabsorption syndromes in children: preliminary study]. The determination of fecal fat gives a reliable index for studying fat intestinal absorption in children, but requires the collection of whole day stools for 3 consecutive days. To avoid stool collection constraint, the authors implemented a 3-point short-duration fatty meal test with determination of subsequent increase in serum levels of triglycerides and chylomicrons which then were compared to fasting values. Normal values were determined among control healthy children. Five patients with diagnosed malabsorption syndromes showed markedly impaired results. This fatty meal test seemed simple, easy to perform during a full-day admission. Further studies are being implemented to confirm its good diagnostic value.


[Evaluation of campaign promoting restraint systems for children in automobiles]. Car collisions are a major cause of death in young children. Many of these deaths could be avoided by using child restraint systems. In May 1990, an illustrated leaflet, describing the utility for a child to be seated on the backseat and belted, was distributed to all children in the primary schools of the Rhône department. To assess the impact of this program "Ceint et sauf" (belted and safe), questionnaires were filled by teachers, once before, and twice after leaflets were distributed. These questionnaires allowed to estimate, in each classroom, the proportion of children who were seated and belted on the backseat during the last day of the preceding week. Answers to questionnaires were received from 673 out of the 5,249 classrooms of the Rhône department (12.8%). The sample was representative with regard to public-private sector, geographical area, and size of schools. Among those who were on the backseat, the proportion of children who were belted increased from 32 to 47%. The proportion of children correctly protected remained low: at the end of the program, only 39% of all children were on the backseat and belted. Despite a methodology unadequate for evaluation, this survey underlined the low level of protection of children in cars in France. Other actions, well evaluated, are needed to promote the use of child restraint systems in France.


[Rectal angioma ruptured into the peritoneum]. The authors report on a case of rectal hemangioma ruptured into the peritoneum, successfully treated by a conservative surgical procedure. The problems associated with diagnosis and treatment are discussed.


[Anorectal manometry in children].

[Anorectal manometry in children]. Ano-rectal manometry is a way of investigation for ano-rectal sphincters. The author overviews anatomical and physiological bases. The manometric technique and its applications in children with Hirschsprung disease or chronic constipation--with or without encopresis--is related.


[Fluctuations of biological rhythms, behavior and intellectual activity in children in different environments]. We report in this paper research data which deal with the fluctuations of biological, biopsychological and intellectual variables throughout the day and week in children and adolescents attending various educational establishments. The first chapter is devoted to the evolution of sleep-arousal alternations from the second year of life and to the relations between this evolution and behavioral and physiological variations during the day. It is divided into four parts: temporal evolution of the sleep-wake rhythm of children from 2 to 5 years of age, attending kindergarten; modifications observed in the behavior and biological rhythms of children from the last year of kindergarten to the first year of primary school; the high variability of biological rhythms from one child to another; modifications observed in intellectual performances of children attending primary and secondary school. The second chapter is devoted to the evolution of the duration of night sleep during childhood and the self-regulation phenomena that it reveals. The overall data lead to suggestions for organizing school schedules throughout the day and week.


[Neonatal Campylobacter fetus septicemia: a case secondary to maternal-fetal contamination]. A favourable outcome of a severe Cambylobacter fetus sepsis in a neonate is reported. The transmission was probably vertical. His mother experienced diarrhoea 15 days before birth. No infecting organism was isolated from maternal stools, but maternal antibody response was significant. Such a perinatal infection with meningitis and septicemia is uncommon. Bacteriological diagnosis requires an enriched medium and a long incubation. The diagnosis should be evoked in view of an anamnestic context, a negative culture or a resistance to antimicrobial drugs.


[Recurrent fever episodes in an African child: diagnostic difficulties of trypanosomiasis in France]. A young Angolian boy who had emigrated to France at the age of 2, presented with a long history of fever. Gambian Trypanosomiasis was diagnosed with peculiar aspects: 1) evolution of adult sickness with a long hemolymphatic period (first stage) and a subacute worsening period with neurologic deficit and somnolence (second stage); 2) a possible post-transfusional contamination: the young boy, born in South Angola, a nor-highly endemic area, was transfused at the age of 10 months with the blood of a donor who was subsequently treated for Trypanosomiasis; 3) a suppurating adenopathy; 4) a predominance of IgG within the hypergammaglobulinemia while IgM are the predominant immunoglobulins in this affection; 5) a hepatic toxicity of Difluoromethylornithine.


[Beta-ketothiolase deficiency: a case of ketoacidosis with hyperglycinemia]. Regarding a case of beta-ketothiolase deficiency revealed by ketoacidosis with hyperglycinemia, the authors show the way to diagnose and to treat this disease. Ketoacidosis without hyperglycemia or lactacidemia suggested this diagnosis. Gas chromatography-mass-spectrography revealed unusual urinary excretion of metabolic products of isoleucine. The enzymological study of fibroblasts confirmed the diagnosis. The treatment of acute episodes consisted of acidosis control and exclusive glucides intake before diagnosis. Afterwards, a controlled proditic diet and L-carnitine must be given and fasting must be avoided.


[Diagnosis of aspartylglycosaminuria in a nine year-old girl admitted to pediatric psychiatry]. A nine year-old, mentally retarded girl was admitted because of growth retardation and recurrent respiratory infections. The lysosomal storage disease was ascertained by microscopic examination of bone marrow and gum biopsies. The diagnosis was provided by urine chromatography: the glycoasparagine Glc-Nac-Asn was characteristic of patients with aspartylglycosaminuria.


[Acute laryngitis in children].

[Acute laryngitis in children]. Acute laryngitis is the most common form of upper airway obstruction in young children. Laryngeal obstruction requiring hospitalization and sometimes intubation may be due to viral infection or occasionally to allergic reaction. The natural course of the disease is impossible to predict; therefore, repeated clinical assessments are needed. Continuous worsening of dyspnea may suggest a diagnosis of bacterial tracheitis. High doses of corticosteroids combined with aerosolized racemic epinephrine can relieve the respiratory difficulties.


[Pyloric stenosis in infants. Contribution of ultrasonography and video-surgery]. Hypertrophic pyloric stenosis is the commonest condition requiring abdominal surgery in infancy. The Fredet-Ramstedt pyloromyotomy gives a very rare morbidity rate as shown by a review of 300 personal cases. The diagnostic value of sonography is gaining significance over contrast roentgenography, a pyloric diameter of more than 14 mm and a muscular thickness of more than 4 mm being required for the diagnosis. Over the last 18 months, we performed extramucosal pyloromyotomies using laparoscopy in 19 infants. This new surgical technique using laparoscopy with precautionary measures for the pneumoperitoneum appears to be very promising and should become a widespread technique in the future.


[Tracheotomy in children. Indications, major surgical principles, importance of nursing]. Tracheotomy in children has two main fields of indication: 1) obstructions of the upper respiratory tract, the main cause being today the post-intubation stenosis; 2) long term mechanical ventilation. When performed in good conditions, with adapted care, there are few complications, among them the accidental denaculation being the most worrying. When long-term tracheotomy is needed, parent-education, together with special equipment and adapted environment may allow the return of the tracheotomised child at home in secure conditions. Special attention with preventive measures during intubation is recommended in order to reduce the number of tracheotomies for post-intubation stenosis.


[Mediastinal bronchogenic cyst of the carina in an infant: contribution of magnetic resonance]. The case of a young child who demonstrated extrinsic narrowing of the thoracich trachea related to a mediastinal bronchogenic cyst is reported. Diagnosis was made by magnetic resonance imaging. About this case report, the authors review the possible causes of tracheal narrowing at this age of life and suggest a simple diagnostic management protocol.


Azithromycin--spectrum of activity, pharmacokinetics, and clinical applications. Azithromycin is an azalide antimicrobial agent. Structurally related to the macrolide antibiotic erythromycin, its mechanism of activity (similar to erythromycin) is interference with bacterial protein synthesis by binding to the 50S component of the 70S ribosomal subunit. Although slightly less potent than erythromycin against gram-positive organisms, azithromycin demonstrates superior activity in vitro against a wide variety of gram-negative bacilli, including Haemophilus influenzae. Absorption is approximately 37% after a 500-mg oral dose. The large volume of distribution (23 L/kg) and low peak serum level (0.4 micrograms/ml) are consistent with data demonstrating extensive tissue distribution and intracellular accumulation. Metabolism is predominantly hepatic (to inactive metabolites), with biliary excretion a major pathway of elimination. Drug elimination is biphasic, with a terminal half-life of up to 5 days. Published trials have examined the efficacy and safety of azithromycin in the treatment of adults with upper and lower respiratory tract infections, skin and skin structure infections, streptococcal pharyngitis, and sexually transmitted diseases. Many used a 5-day course of 250 mg once daily, supplemented with a 250-mg dose on the first day of therapy. Selected trials in sexually transmitted diseases examined single 1-g doses. Promising results also were obtained with oral daily doses of 500 mg in patients with human immunoviral infection who also had Mycobacterium avium complex infection and in animals with toxoplasmosis. Adverse reactions are primarily gastrointestinal (nausea, diarrhea, abdominal pain), with minimal laboratory abnormalities reported. Gastrointestinal tolerance is better than that of erythromycin. Drug interactions have not been observed to date, although coadministration of azithromycin with a large meal may reduce absorption by up to 50%.


A transgene, alv6, that expresses the envelope of subgroup A avian leukosis virus reduces the rate of congenital transmission of a field strain of avian leukosis virus. A major mode of transmission of avian leukosis virus (ALV) is from a dam that is viremic with and immunologically tolerant to ALV, through the egg to the progeny. The authors have produced a line of chickens transgenic for a defective ALV provirus that expresses envelope glycoprotein, but not infectious virus, and is very resistant to infection with Subgroup A ALV. In the present experiment the authors sought to prevent or reduce congenital transmission by mating viremic-tolerant hens to males carrying the inserted provirus, thus introducing a gene for resistance into the progeny. Mature viremic females were mated with males hemizygous for the transgene to produce over 80 progeny each with and without the transgene. The chicks were hatched and maintained for 36 wk and observed for viremia, antibody, and the incidence of bursal lymphomas. Over 90% of the transgene-negative controls remained viremic through 36 wk of age and 51% developed bursal lymphomas. In contrast, 27% of the transgene-positive birds remained viremic and 18% died with bursal lymphomas. Thus, expression of Subgroup A envelope protein in the developing embryo reduced but did not eliminate congenital infection.


The effect of sodium zeolite A and cholecalciferol on plasma levels of 1,25-dihydroxycholecalciferol, calcium, and phosphorus in commercial Leghorns. Three experiments were conducted to determine possible mechanisms involved in improving eggshell quality with sodium zeolite A (SZA) (trade name Ethacal feed component), and cholecalciferol (vitamin D3) by studying the effect of dietary supplementation of SZA and vitamin D3 on plasma 1,25-dihydroxycholecalciferol [1,25-(OH)2 D3], ionic calcium (Ca++), normalized calcium (nCa++), total calcium (TCa), percentage Ca++ to TCa (PCa++), pH, and phosphorus (P). In Experiment 1 (2 x 2 factorial arrangement of treatments), two levels of SZA (0 and .75%) and two levels of vitamin D3 (0 and 175 ICU/kg) were fed. In Experiment 2, five levels of vitamin D3 (100 to 500 ICU/kg) and two levels of SZA (0 and .75%) were fed using a 2 x 5 factorial arrangement of treatments. In Experiment 3, hens were fed two levels of SZA (0 and .75%). Blood samples were collected at 0 (Experiments 1, 2, and 3), 7, 14, and 21 h (Experiment 3) postoviposition (POP). In Experiments 1 and 2, decreasing vitamin D3 decreased plasma 1,25-(OH)2 D3 and P. Plasma TCa decreased when 0 ICU vitamin D3 was fed (Experiment 1), but was not affected by vitamin D3 level in Experiment 2. Supplemental SZA had no effect on plasma 1,25-(OH)2 D3, TCa, or P in Experiments 1 and 2. In Experiment 3, plasma 1,25-(OH)2 D3 and P peaked at 14 h POP, but Ca++ was lowest at 14 h POP. Circadian rhythms for plasma 1,25-(OH)2 D3, Ca++, and P were not affected by SZA. There were no significant effects due to dietary SZA on plasma 1,25-(OH)2 D3, TCa, Ca++, PCa++, nCa++, pH, or P.(ABSTRACT TRUNCATED AT 250 WORDS)


Effect of water mobility on drug hydrolysis rates in gelatin gels. The stability of drugs incorporated in gelatin gels was studied, with a focus on the water mobility in the gels. Trichlormethiazide hydrolysis and kanamycin-catalyzed flomoxef hydrolysis in gelatin gels were chosen as models for apparent first-order and second-order hydrolysis, respectively. The mobility of water in gelatin gels was determined by NMR, ESR, and dielectric relaxation spectroscopies. The amount of bound water in the gels was determined from dielectric relaxation spectra. Spin-lattice relaxation time of water determined by 17O NMR and rotational correlation time of an ESR probe determined by an ESR probing method were useful in determining the microviscosity of the gels. The hydrolysis rate of trichlormethiazide in the gels was found to depend on the amount of free water available for the reaction, while that of flomoxef depended on the microviscosity of the gels, which reflected the mobility of water molecules. Thus the dependence of hydrolysis rates on the water mobility was influenced by the hydrolysis mechanism.


Accumulation of potassium and calcium in rat myocardium exposed to alpha-1-adrenoceptor stimulation. Net fluxes of potassium, calcium, sodium and chloride were examined in isolated perfused rat hearts during alpha-1-adrenoceptor stimulation. The ion measurements were performed in the non-recirculating perfusate. Hearts were exposed to alpha-1-adrenoceptor stimulation (phenylephrine 5 x 10(-5) mol/l in the presence of the beta-blocker timolol 10(-6) mol/l). During alpha-1-adrenoceptor stimulation perfusate potassium fell relatively rapidly by about 0.10 mmol/l after approximately 100 sec. followed by a slower rise. About 180 sec. after onset of alpha-1-adrenoceptor stimulation, the potassium level was about 0.06 mmol/l below the control concentration level. This reduction was eliminated by the alpha-1-adrenoceptor blocker prazosin (10(-7) mol/l). The effects on net calcium fluxes were measured at two different calcium concentrations. For both concentrations we found a small but statistically significant reduction of the calcium concentration in the perfusate after alpha-1-adrenoceptor stimulation. Neither sodium nor chloride perfusate concentrations showed statistical significant changes compared to control values. The present observations revealed the existence of alpha-1-adrenoceptor regulated mechanisms related to a net uptake of both potassium and calcium in rat heart.


Cadmium mobilization in vivo by intraperitoneal or oral administration of monoalkyl esters of meso-2,3-dimercaptosuccinic acid in the mouse. The relative activities of a series of nine monoalkyl esters of meso-2,3-dimercaptosuccinic acid have been examined as agents for the mobilization of cadmium from mice one week after intraperitoneal administration of cadmium chloride. Eight of these are newly synthetized; all are of the type ROOCCH(SH)CH(SH)COOH, were R = Me, MMDMS; R = C2H5, MEDMS; R = (CH2)2CH3, Mn-PDMS; R = CHMe2, Mi-PDMS; R = (CH2)3CH3, Mn-BDMS; R = CH2CHMe2, Mi-BDMS; R = (CH2)4CH3, Mn-ADMS; R = (CH2)2CHMe2, Mi-ADMS; and R = (CH2)5CH3, Mn-HDMS. All are soluble in dilute sodium bicarbonate solutions and can be administered as aqueous solutions. Cadmium mobilization data were collected on each compound using mice previously loaded with cadmium; the monoesters were administered at a level of 0.40 mmol/kg intraperitoneally daily for five days. Data on whole body cadmium mobilization indicated that the monoester with the isoamyl group was the most effective under the conditions used. The relative whole body cadmium mobilization increased with the number of carbon atoms in the alkyl group of the monoester up to C5 and then decreased for the C6 compound. Cadmium removal from the kidneys and liver was also measured. It was found that the monoisoamyl ester was the most effective in removing cadmium from both the liver and the kidneys. The monoisoamyl ester also proved to be very effective in mobilizing cadmium from both the liver and the kidneys when given orally. This is the first compound which is reported capable of mobilizing cadmium in vivo from aged deposits after oral administration.


The phorbol ester-dependent activator of the mitogen-activated protein kinase p42mapk is a kinase with specificity for the threonine and tyrosine regulatory sites. Mitogen-activated protein kinases (MAP kinases) are activated by dual tyrosine and threonine phosphorylations in response to various stimuli, including phorbol esters. To define the mechanism of activation, recombinant wild-type 42-kDa MAP kinase (p42mapk) and a kinase-defective mutant of p42mapk (K52R) were used to assay both activator activity for p42mapk and kinase activity toward K52R in stimulated EL4.I12 mouse thymoma cells. Phorbol 12,13-dibutyrate (10 min, 650 nM) stimulated a single peak of MAP kinase activator that was coeluted from Mono Q at pH 7.5 and 8.9 with K52R kinase activity. Both activities were inactivated by the serine/threonine-specific phosphatase 2A but not by the tyrosine-specific phosphatase CD45. Phosphorylation of K52R occurred specifically on Thr-183 and Tyr-185, as determined by tryptic phosphopeptide mapping in comparison with synthetic marker phosphopeptides. These findings indicate that phorbol ester-stimulated MAP kinase kinase can activate p42mapk by threonine and tyrosine phosphorylations, and that p42mapk thus does not require an autophosphorylation reaction.


Role of protein kinase C and transcription factor AP-1 in the acid-induced increase in Na/H antiporter activity. Chronic incubation of cultured renal tubular epithelial cells in acid medium causes an increase in Na/H antiporter activity that persists after removal from acid, is dependent on protein synthesis, and is associated with an increase in Na/H antiporter mRNA. Chronic activation of protein kinase C has similar effects in these cells. The present studies examined the role of protein kinase C in the effect of acid incubation. Incubation of MCT cells in acid for 24 h caused a 50% increase in Na/H antiporter activity. This was prevented by inhibition of protein kinase C, either with sphingosine or by protein kinase C downregulation. Pertussis toxin pretreatment did not prevent the increase in antiporter activity. Acid incubation caused an increase in transcription factor AP-1 activity, as shown by an increase in expression from a reporter gene containing six tandem AP-1 binding sites. This was associated with transient increases in c-fos and c-jun mRNAs. This response is typical of that for gene activation by protein kinase C. These studies demonstrate that acid activation of the Na/H antiporter requires protein kinase C and is associated with c-fos and c-jun expression and increased AP-1 activity.


[Buschke-Loewenstein's tumor].

[Buschke-Loewenstein's tumor]. Buschke-Loewenstein tumour, also called giant condyloma acuminatum, is located on the external genitalia and in the perineal region. It presents as a craggy, burgeoning and locally invasive mass that looks clinically worrying. Histology shows a classically benign papillomatous proliferation, but transformation into invasive carcinoma occurs in about one-third of the cases. Local penetration and sometimes focal cytological atypias have prompted certain authors to use the term verrucous carcinoma. Virological studies have demonstrated the presence, in some of the tumours analysed, of human papilloma virus type 6 and/or 11 DNA appearing as free episomes non integrated within the cellular genome.


Human cytomegalovirus origin of DNA replication (oriLyt) resides within a highly complex repetitive region. A global analysis of the 230-kilobase-pair (kbp) human cytomegalovirus genome revealed three regions that were very rich in repeated sequences. The region with the highest content of inverted and direct repeats lies between 92,100 and 93,500 bp, upstream of the gene encoding the single-stranded DNA binding protein. Cloned restriction fragments containing this region were able to replicate when trans-acting factors were provided by virus infection in a transient replication assay. With this assay, the region between 92,210 and 93,715 bp on the viral genome was defined as the minimal replication origin, oriLyt. The sequence composition and repeats within oriLyt were used to divide the region into two domains that may be important in origin function. Sequences flanking either the left or right side of the minimal oriLyt contributed to efficient replication; however, these sequences were not essential for origin function. Thus, the region of the viral genome with the most striking concentration of direct and inverted repeats corresponds to the oriLyt of human cytomegalovirus.


Rapid evolution of the human gene for cytochrome c oxidase subunit IV. We have compared the DNA sequences of nine mammalian genes for cytochrome c oxidase subunit IV (COX4 genes)--four expressed genes (human, bovine, rat, and mouse) and five pseudogenes (human, chimpanzee, orangutan, squirrel monkey, and bovine)--and constructed the sequence of the ancestral mammalian COX4 gene. By analyzing these sequences to determine the pattern and rate of nucleotide substitution in each branch of the evolutionary tree, we deduced that the human gene has evolved rapidly since the origin of the primate pseudogene approximately 41 million years ago, and we discuss the suggestion that this results from coevolution of nuclear and mitochondrial genes for cytochrome c oxidase.


A 71-kilodalton protein is a major product of the Duchenne muscular dystrophy gene in brain and other nonmuscle tissues. The known Duchenne muscular dystrophy (DMD) gene products, the muscle- and brain-type dystrophin isoforms, are 427-kDa proteins translated from 14-kilobase (kb) mRNAs. Recently we described a 6.5-kb mRNA that also is transcribed from the DMD gene. Cloning and in vitro transcription and translation of the entire coding region show that the 6.5-kb mRNA encodes a 70.8-kDa protein that is a major product of the DMD gene. It contains the C-terminal and the cysteine-rich domains of dystrophin, seven additional amino acids at the N terminus, and some modifications formed by alternative splicing in the C-terminal domain. It lacks the entire large domain of spectrin-like repeats and the actin-binding N-terminal domain of dystrophin. This protein is the major DMD gene product in brain and other nonmuscle tissues but is undetectable in skeletal muscle extracts.


Growth-stimulatory monoclonal antibodies against human insulin-like growth factor I receptor. Monoclonal antibodies (mAbs) against purified human placental insulin-like growth factor I (IGF-I) receptors were prepared and characterized. Three IgG mAbs were specific for the human IGF-I receptor and displayed negligible crossreactivity with the human insulin receptor. They stimulated 125I-labeled IGF-I (125I-IGF-I) or 125I-IGF-II binding to purified human placental IGF-I receptors and to IGF-I receptors expressed in NIH 3T3 cells in contrast to the well-studied mAb alpha IR-3, which inhibits 125I-IGF-I or 125I-IGF-II binding to both forms of IGF-I receptors. The mAbs introduced in this study stimulated DNA synthesis in NIH 3T3 cells expressing human IGF-I receptors approximately 1.5-fold above the basal level and the IGF-I- or IGF-II-stimulated level. In contrast, alpha IR-3 inhibited both basal and IGF-I or IGF-II-stimulated DNA synthesis by approximately 30%. Inhibition of IGF-II-stimulated DNA synthesis by alpha IR-3 was as potent as its inhibition of IGF-I-stimulated DNA synthesis, although IGF-II binding to the IGF-I receptors was not inhibited by IGF-II as potently as was IGF-I. With the purified IGF-I receptors, both inhibitory and stimulatory mAbs were shown to activate autophosphorylation of the IGF-I receptor beta subunit and to induce microaggregation of the receptors. These results suggest that conformational changes resulting from receptor dimerization in the presence of either type of mAb may affect the signal-transducing function of the IGF-I receptor differently. These additional mAbs and alpha IR-3 immunoprecipitated nearly 90% of IGF-I binding activity from Triton X-100-solubilized human placental membranes, indicating that IGF-I receptor reactive with these mAbs is the major form of the IGF-I receptor in human placenta.


Mls-1 is encoded by the long terminal repeat open reading frame of the mouse mammary tumor provirus Mtv-7. The murine Mls-1 antigen is the prototype of endogenous superantigens, molecules whose activities lead to deletion of T cells expressing certain T-cell receptor V beta genes from the mature repertoire. However, Mls-1 also stimulates T cells expressing these particular V beta genes (V beta 6, V beta 7, V beta 8.1, and V beta 9) in vitro, making it one of the strongest known T-cell activators. We have recently reported that the Mls-1 gene is closely linked to the endogenous mammary tumor virus Mtv-7. We now demonstrate that Mls-1 is encoded by the open reading frame in the U3 region of the long terminal repeat of Mtv-7. However, control of expression of this molecule seems complex, depending on the promoter used for the transfection experiments. The sequence of the Mtv-7 open reading frame differs from all other known mammary tumor virus open reading frame sequences in the 3' end, suggesting that the T-cell receptor V beta specificity is conferred by the C terminus of the molecule. The predicted structure of the protein encoded by the open reading frame is consistent with a type II transmembrane molecule where the C terminus is extracellular.


Evidence for in vitro replication of hepatitis C virus genome in a human T-cell line. A human T-cell line, MOLT-4, either uninfected or infected with murine retroviruses, was tested for its susceptibility to hepatitis C virus (HCV) infection. The cell cultures were inoculated with a serum containing HCV and then examined for the presence of viral sequences by cDNA/PCR. In murine retrovirus-infected MOLT-4 (MOLT-4 Ma) cells, intracellular minus-strand viral RNA, a putative replication intermediate, was first detected 3 days after inoculation, and the maximum signal was seen on day 7. When the cells were continuously subcultured in fresh medium, HCV sequences were intermittently detected in cells over a period of 3 weeks. In MOLT-4 cells free of retroviruses, replication of minus-strand HCV RNA appeared less efficient than in MOLT-4 Ma cells. The presence of minus-strand viral RNA in MOLT-4 Ma cells inoculated with HCV was confirmed by in situ hybridization with a strand-specific RNA probe. Immunofluorescence tests with antibodies specific for HCV core and NS4 antigens showed that MOLT-4 Ma cells were positive for viral antigen 7 days after inoculation. Thus, it appears likely that the HCV genome can replicate in the human T-cell line MOLT-4.


Nonrandom integration of retroviral DNA in vitro: effect of CpG methylation. We have developed a PCR-based system that allows us to assess the relative frequency of use of specific bases as targets for the avian leukosis virus in vitro integration system. Using this system, we tested the effect of 5-methylation of cytosine in runs of CpG on the distribution of integration target sites. We found that the distribution of preferred integration sites was not uniform along the target DNA; rather, there was a distinct and reproducible pattern of frequently used sites. This pattern was independent of orientation of the integrated DNA, and of overall structure and sequence of the target and fragment amplified. Methylation did not inhibit integration into CpG dinucleotides; on the contrary, this modification created highly preferred targets within runs of alternating CpG. Finally, similar but not identical specificity was observed by using preintegration complexes in infected extracts or purified integrase and DNA as enzyme and substrate. Thus, most of the specificity observed is conferred by interaction of integrase and targets, although it may be modified by other viral and/or cellular components.


Oxoammonium cation intermediate in the nitroxide-catalyzed dismutation of superoxide. Dismutation of superoxide has been shown previously to be catalyzed by stable nitroxide compounds. In the present study, the mechanism of superoxide (.O2-) dismutation by various five-membered ring and six-membered ring nitroxides was studied by electron paramagnetic resonance spectrometry, UV-visible spectrophotometry, cyclic voltammetry, and bulk electrolysis. Electron paramagnetic resonance signals from the carbocyclic nitroxide derivatives (piperidinyl, pyrrolidinyl, and pyrrolinyl) were unchanged when exposed to enzymatically generated .O2-, whereas, in the presence of .O2- and reducing agents such as NADH and NADPH, the nitroxides underwent reduction to their respective hydroxylamines. The reaction of 4-hydroxy-2,2,6,6-tetramethyl-1-hydroxypiperidine (Tempol-H) with .O2- was measured and, in agreement with earlier reports on related compounds, the rate was found to be too slow to be consistent with a mechanism of .O2- dismutation involving the hydroxylamine as an intermediate. Voltammetric analyses of the carbocyclic nitroxide derivatives revealed a reversible one-electron redox couple at positive potentials. In contrast, oxazolidine derivatives were irreversibly oxidized. At negative potentials, all of the nitroxides studied exhibited a broad, irreversible reductive wave. The rate of .O2- dismutation correlated with the reversible midpoint redox potential. Bulk electrolysis at positive potentials was found to generate a metastable oxidized form of the nitroxide. The results indicate that the dismutation of .O2- is catalyzed by the oxoammonium/nitroxide redox couple for carbocyclic nitroxide derivatives. In addition to the one-electron mitochondrial reduction pathway, the present results suggest the possibility that cellular bioreduction by a two-electron pathway may occur subsequent to oxidation of stable nitroxides. Furthermore, the cellular destruction of persistent spin adduct nitroxides might also be facilitated by a primary univalent oxidation.


Tight control of gene expression in mammalian cells by tetracycline-responsive promoters. Control elements of the tetracycline-resistance operon encoded in Tn10 of Escherichia coli have been utilized to establish a highly efficient regulatory system in mammalian cells. By fusing the tet repressor with the activating domain of virion protein 16 of herpes simplex virus, a tetracycline-controlled transactivator (tTA) was generated that is constitutively expressed in HeLa cells. This transactivator stimulates transcription from a minimal promoter sequence derived from the human cytomegalovirus promoter IE combined with tet operator sequences. Upon integration of a luciferase gene controlled by a tTA-dependent promoter into a tTA-producing HeLa cell line, high levels of luciferase expression were monitored. These activities are sensitive to tetracycline. Depending on the concentration of the antibiotic in the culture medium (0-1 microgram/ml), the luciferase activity can be regulated over up to five orders of magnitude. Thus, the system not only allows differential control of the activity of an individual gene in mammalian cells but also is suitable for creation of "on/off" situations for such genes in a reversible way.


Viricidal effect of stimulated human mononuclear phagocytes on human immunodeficiency virus type 1. Human monocytes stimulated with phorbol 12-myristate 13-acetate or opsonized zymosan in vitro were viricidal to human immunodeficiency virus type 1 (HIV-1) as measured by the inability of the virus to replicate in CEM cells. Monocytes, when stimulated, release myeloperoxidase (MPO) and produce H2O2; MPO reacts with H2O2 and chloride to form hypochlorous acid, a known microbicidal agent. The viricidal activity of stimulated monocytes was inhibited by the peroxidase inhibitor azide, implicating MPO, and by catalase but not heated catalase or superoxide dismutase, implicating H2O2. Stimulated monocytes from patients with chronic granulomatous disease (CGD) or hereditary MPO deficiency were not viricidal to HIV-1 unless they were supplemented with the H2O2-generating enzyme glucose oxidase or MPO, respectively. The viricidal activity of stimulated, glucose oxidase-supplemented CGD monocytes and MPO-supplemented MPO-deficient monocytes, like that of normal stimulated monocytes, was inhibited by azide and catalase. Monocytesmaintained in culture differentiate into macrophages with loss of MPO and decreased H2O2 production. The viricidal activity of 3- to 9-day monocyte-derived macrophages was decreased unless MPO was added, whereas the loss of viricidal activity by 12-day-old monocyte-derived macrophages was not reversed by MPO unless the cells were pretreated with gamma-interferon. These findings suggest that stimulated monocytes can be viricidal to HIV-1 through the release of the MPO/H2O2/chloride system and that the decreased viricidal activity on differentiation to macrophages results initially from the loss of MPO and, with more prolonged culture, also from a decreased respiratory burst that can be overcome by gamma-interferon.


cAMP-mediated differential regulation of lignin peroxidase and manganese-dependent peroxidase production in the white-rot basidiomycete Phanerochaete chrysosporium. Lignin peroxidases (LIPs) and manganese-dependent peroxidases (MNPs) are major components of the lignin-degrading enzyme system of Phanerochaete chrysosporium and typically appear during secondary metabolism. The involvement of cAMP in the regulation of production of LIPs and MNPs was investigated in this study. Production of LIPs and MNPs was preceded by a sharp rise in intracellular cAMP concentration. Addition of atropine, theophylline, or histamine to cultures resulted in a drop in intracellular cAMP concentration and a concomitant inhibition of production of LIPs only or of both LIPs and MNPs, depending on the concentration of the inhibitor added. These results were independently confirmed by fast protein liquid chromatographic profiles of the LIPs and MNPs in the extracellular fluid of the inhibitor-treated and untreated control cultures. LIP production was generally more sensitive to the inhibitors than MNP production. Northern blot analyses showed that the inhibitors affect the production of LIPs and MNPs at the level of transcription. Furthermore, LIP and MNP gene expression appears to be differentially regulated depending on the intracellular concentration of cAMP. These results show that cAMP plays a key role in the regulation of production of LIPs and MNPs in P. chrysosporium.


Induction of the mobile genetic element Dm-412 transpositions in the Drosophila genome by heat shock treatment. Males of a Drosophila melanogaster isogenic line with a mutation of the major gene for radius incompletus (ri) were treated by standard light heat shock (37 degrees C for 90 min) and by heavy heat shock (transfer of males from 37 degrees C for 2 hr to 4 degrees C for 1 hr and back; this procedure was repeated three times). In the F1 generation of treated males mated with nontreated females of the same isogenic line, mass transpositions of copia-like mobile genetic element Dm-412 were found. The altered positions of the element seem nonrandom; five "hot spots" of transposition were found. Probabilities of transpositions were estimated after light heat shock and heavy heat shock and in the control sample. These probabilities were, respectively, 3.4 x 10(-2), 8.7 x 10(-2), and less than 4.1 x 10(-4) transpositions per genome per occupied position per generation. Therefore, as a result of heat shock treatment, the probabilities of transpositions were two orders of magnitude greater than those of the control sample in the next generation after induction. Comparison of the results with those after stepwise temperature treatment shows that the induction depends on the intensity of the stress action (temperature treatment) rather than on the type of the stress action.


Localization of bovine papillomavirus type 1 E5 protein to transformed basal keratinocytes and permissive differentiated cells in fibropapilloma tissue. We examined expression of the E5 transforming protein of bovine papillomavirus type 1 (BPV-1) in naturally and experimentally infected bovine cells. Bovine conjunctival fibroblasts transformed in vitro by experimental infection with purified BPV-1 virions expressed significantly higher amounts of the 7-kDa E5 protein than BPV-1-transformed murine C127 cells. Indirect immunofluourescence analysis revealed a cytoplasmic, predominantly juxtanuclear, localization of E5 protein in the in vitro virus-transformed bovine cells. In naturally infected bovine skin fibropapilloma tissue, two widely separated sites of E5 protein synthesis were identified within the epithelial layers. Transformed basal layer keratinocytes throughout the tumor tissue expressed cytoplasmic E5 protein at a low uniform level. In addition, abundant amounts of cytoplasmic E5 protein with a granular staining pattern were detected in highly differentiated keratinocytes in close association with sites of viral capsid protein synthesis. These observations imply roles for the viral E5 oncogene in the growth transformation of basal epidermal keratinocytes as well as in the differentiation-linked process of viral maturation. Detection of a papillomavirus protein in the basal cell population of warts lends support to the hypothesis that these cells are maintained in a transformed state by continuous expression of a viral transforming gene.


[Utilization of a multiparametric technique for analysis of specificity of different inhibitors of various forms of cyclic nucleotide phosphodiesterases]. Multiple enzymes and compounds were used to study relationship between chemical structure and enzymatic affinity. Reduction of multidimensional data, by mathematical methods, as factorial correspondence analysis (FCA), with simple graphical representation allows to define the relative specificity of various molecules for different enzymatic targets. Using a significative sample of molecule tests and their biological responses it would be possible for each new compound to determine its typology inside its molecular family and to give insight for pharmacological modulation. Papaverine analogues reference drugs and three isolated cyclic nucleotide phosphodiesterase forms were used as experimental model in this analysis.


Oxytocin--a neuropeptide for affiliation: evidence from behavioral, receptor autoradiographic, and comparative studies. Oxytocin (OT) is a nine amino acid peptide synthesized in hypothalamic cells which project either to the neurohypophysis or to sites within the central nervous system. Although neurohypophyseal OT release has long been associated with uterine contraction and milk ejection, the function of intracerebral OT remains unclear. On the basis of behavioral, cellular, and comparative studies, this review suggests that brain OT influences the formation of social bonds. The first part of this review examines evidence linking central OT to several forms of affiliation. Central administration of OT induces maternal and reproductive behaviors in rats primed with gonadal steroids. OT antagonists and hypothalamic lesions block the initiation of maternal and reproductive behaviors but have no effects on these behaviors once established. Our new studies in rat pups demonstrate that central OT selectively decreases the separation response, an effect which mimics social contact. These studies of parental, reproductive, and attachment behaviors suggest that exogenous OT has "prosocial" effects and that endogenous OT may be essential for initiating social interaction. In a second series of experiments, we investigated the cellular mechanisms for OT's effects on social behavior by means of autoradiographic receptor binding. In the rat forebrain, OT receptors are expressed in several limbic regions believed to be involved in the integration of sensory processing. The regulation of these receptors is surprisingly resistant to either ablation of OT cells or repeated central administration of OT. However, receptors in two regions, the bed nucleus of the stria terminalis (BNST) and the ventromedial nucleus of the hypothalamus (VMN), appear selectively induced by exogenous or endogenous increases in gonadal steroids. At parturition, binding to OT receptors increases 84% in the BNST, and at estrus, binding increases 35% in the VMN. These results demonstrate that physiologic changes in gonadal steroids can alter receptor expression in anatomically discrete target fields and thereby direct responsiveness to endogenous neuropeptide release. A model for OT's effects on social behavior is proposed, which relies on the heterologous regulation of the brain OT receptor. A third series of experiments tested the hypothesis that brain OT influences affiliation by comparing prairie and montane voles, two closely related species with dichotomous systems of social organization. Although no differences appear in the presynaptic expression of the neuropeptide, OT receptors are distributed in complementary patterns in the two species. In the highly affiliative prairie vole, receptors are most evident in the BNST and one of its primary afferents, the lateral amygdala, highlighting a circuit previously implicated in maternal behavior.(ABSTRACT TRUNCATED AT 400 WORDS)


Effect of estradiol implant on noradrenergic function and mood in menopausal subjects. The effect of the alpha 2-adrenoceptor agonist, clonidine, on plasma growth hormone (GH), plasma 3-methoxy-4-hydroxyphenylethylenegylcol (MHPG), blood pressure and sedation were studied in 16 menopausal subjects before and 6 wk after a 100-mg implant of estradiol. The specific binding of tritiated yohimbine to intact platelets also was studied. Estradiol implants increased basal GH output and reduced baseline MHPG and sedation scores. However, none of the subsequent responses to clonidine were altered. Platelet yohimbine binding also was unchanged following the implant. Both observer- and self-rating scales showed a marked reduction in anxiety and depression scores. The results suggest that estradiol may alter some indices of noradrenergic function, but that the mechanism does not involve alterations in alpha 2-adrenoceptor sensitivity.


Irradiation increases proteolysis in erythrocyte ghosts: a spin label study. X- and gamma-irradiation of human erythrocyte membranes (250-1000 Gy) was found to decrease the ratio of weakly to strongly immobilized signal height of membrane-bound maleimide spin label (Mal-6). Subsequent incubation of spin-labeled membranes at ambient temperature (21 degrees C) induced a progressive increase in this ratio, faster for membranes irradiated with low doses which was hampered by protease inhibitors. These results demonstrate that ionizing radiation stimulates proteolysis of erythrocyte membrane proteins by membrane-associated proteases.


Cerebral metabolic disturbances in patients with subacute and chronic diabetes mellitus: detection with proton MR spectroscopy. Localized proton magnetic resonance (MR) spectroscopy was used to define biochemical changes in gray and white matter of the cerebral cortex in 22 patients with diabetes mellitus (DM), including 10 episodes of diabetic ketoacidosis (DKA), compared with MR spectra in 30 healthy subjects. Five distinct metabolic abnormalities were identified: Concentrations of glucose (Glc) (P greater than or equal to .002), ketone body or bodies, myo-inositol (P greater than or equal to .003) (with or without glycine), and choline (Cho) metabolites were increased in both white and gray matter, whereas a significant reduction of N-acetyl metabolites was found in the parietal cortex (P greater than or equal to .003). Diurnal variations in the intracerebral concentration of Glc were demonstrated in a patient with DM whose condition was stable. Elevated concentrations of ketones were detected in three episodes and excess Cho in two episodes of DKA. Evidence obtained with hydrogen-1 MR spectroscopy favors acetone rather than acetoacetate as the ketone present in the brain, which is a major target of biochemical change in DM.


Pediatric musculoskeletal tumors: use of dynamic, contrast-enhanced MR imaging to monitor response to chemotherapy. The ability of dynamic, gadolinium-enhanced magnetic resonance (MR) imaging to allow prediction of histologic responses to initial chemotherapy was evaluated in 20 patients with osteosarcoma (n = 12), Ewing sarcoma (n = 4), rhabdomyosarcoma (n = 3), or synovial sarcoma (n = 1). Tumor signal intensity was measured on fast low-angle shot (FLASH) gradient-echo images obtained at 15-second intervals before and 3 or more minutes after manual intravenous injection of gadopentetate dimeglumine. Signal intensity was plotted against time, and slopes were calculated for the percentage increase in signal intensity per minute. Slopes and changes in maximum tumor size during and after chemotherapy were correlated with histologic evaluations of tumor response. Eleven of the 20 tumors met histologic criteria for response. Histologic response was moderately correlated with slopes obtained during chemotherapy (rs [Spearman rank correlation] = .53, P = .02) but not with changes in tumor size (rs = .02, P = .94). Tumor slopes obtained after chemotherapy were highly correlated with histologic findings (rs = .65, P = .007); the correlation with changes in tumor size increased but remained nonsignificant (rs = .41, P = .11).


Galactosemia: evaluation with MR imaging. The cerebral findings at magnetic resonance imaging in 67 transferase-deficient galactosemic patients (36 female, 31 male; median age, 10 years) are reported. Twenty-two patients had mild cerebral atrophy, eight had cerebellar atrophy, and 11 had multiple small hyperintense lesions in the cerebral white matter on T2-weighted images. The classic galactosemic patients (those without measurable transferase activity) older than 1 year of age did not show the normal dropoff in peripheral white matter signal intensity on intermediate- and T2-weighted images. The authors postulate that this abnormal signal intensity is due to altered myelin formation secondary to the inability to make sufficient and/or normal galactocerebroside.


Fine-needle aspiration of breast biopsy specimens: correlation of histologic and cytologic findings. The accuracy of fine-needle aspiration (FNA) cytologic diagnosis of nonpalpable breast lesions and the prevalence of neoplasm occurring in areas unrelated to the radiologic abnormality were studied. Template-guided FNA cytologic examination was performed in 101 surgically excised breast specimens. The exact area of the mammographic abnormality was aspirated with radiographic control. Despite accurate placement of the needle for aspiration, seven of 101 aspirates (7%) yielded insufficient cytologic material. Ninety-four of the 101 aspirates (93%) were adequate for diagnosis. The cytologic diagnosis was benign in 58 (62%), atypical in seven (7%), suspicious for malignancy in four (4%), and malignant in 25 (27%). All cases diagnosed as suspicious or malignant and five of 58 cases diagnosed as benign at cytologic examination proved to be malignant at histologic examination. In three of these five the malignancy was in the area of the radiologic abnormality; in two it was not. FNA cytologic examination can be helpful in evaluating nonpalpable breast lesions, but it is not as accurate as histologic examination of surgically excised lesions.


Corticotropin-secreting carcinoid tumors of the thymus: diagnostic unreliability of thymic venous sampling. Three patients with Cushing syndrome due to ectopic production of corticotropin underwent total thymectomy on the basis of elevated concentrations of corticotropin in selective samples from thymic veins but in the absence of a radiographically detectible thymic mass. In one patient, radiologic examination demonstrated hyperplasia of neuroendocrine cells staining positively for corticotropin throughout the thymus but no discrete mass. This patient had complete remission after total thymectomy. The other two patients had no evidence of an intrathymic source of corticotropin, and both had persistent Cushing syndrome. Elevated levels of corticotropin in thymic vein samples may reflect corticotropin production by pulmonary bronchial carcinoid tumors, mediastinal metastases, thymic carcinoids, or diffuse hyperplasia of intrathymic neuroendocrine elements. In the absence of a demonstrable intrathymic mass, corticotropin gradients in thymic veins do not reliably indicate a thymic source of corticotropin and should not necessarily be used as a basis for exploratory thoracotomy or blind thymectomy.