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E Simon

Publications and source records attributed to E Simon.

At least 91 records · Page 5Linked to original sources
PubMed1996

[New possibility in inguino-femoral hernia repair: laparoscopic herniaplasty].

The development of minimally invasive surgery brought up the challenge: to repair the frequent inguino-femoral hernias laparoscopically. The authors performed 65 laparoscopic hernioplasties in one year: "transabdominal preperitoneal" technique was used in 61 cases und "intraperitoneal onlay mesh" in 4 cases. Fifty-three patients were operated on, 12 of them had bilateral hernias. Recurrent hernia was the indication in 22 patients (34%). The average operating time was 102 and 144 minutes in the unilateral and the bilateral cases, respectively. There was no wound infection, or general complication. Spontaneously dissolving seroma/hematoma of the spermatic cord was noticed and detected by ultrasound in 5 patients (7.7%). The neuralgia caused by the irritation of the nerves of the region in 4 patients (6.1%) disappeared without sequels after treatment with vitamins B. The 2 early recurrences (3.2%), considered to be caused by technical inexperience, these patients were treated successfully with the "intraperitoneal onlay mesh" technique. In the authors' opinion there are definite advantages of laparoscopic hernioplasty, namely the minimal postoperative pain, early mobilization, shorter hospital stay and early restoration of full physical activity (in 1-2 weeks) as well as the known disadvantages of this technique (narcosis, longer operative time, intraperitoneal procedure, higher costs).

Adult↗
PubMed1996

Hormonal secretion patterns but not autonomic effector responses elicited by hypothalamic heating and cooling are altered in febrile rabbits.

The effects of hypothalamic heating and cooling on thermoregulatory effector activities, lipid and carbohydrate metabolism, insulin, glucagon, thyroxine, arginine vasopressin (AVP) and cortisol were investigated in conscious rabbits and compared with those obtained in the febrile state. The study shows that under control conditions hypothalamic heating lowers, and cooling raises core temperature. Core temperature always rose to similar degrees in response to bacterial lipopolysaccharide (LPS) during an observation time of 150 min, but it started to rise from lower and higher levels, respectively, during hypothalamic heating and cooling. The effects of hypothalamic thermal stimulation on specific thermoregulatory effector activities support the conclusion that, within 60 min after LPS, the hypothalamic warm signal input is reduced relative to the cold signal input. The increase of thyroxine levels following LPS suggests that the elevation of the thermoregulatory setpoint was caused by an increased input of hypothalamic TRH neurons, known to induce the full autonomic pattern of cold defense also in response to non-thermal stimuli. With the exception of an increase of glucagon during hypothalamic cooling at control conditions, hypothalamic thermal stimulation alone did not alter lipid and carbohydrate metabolism, insulin, thyroid hormone, AVP and cortisol secretion. A spontaneous heat loss effector response separated the first from the second fever phase 60 min after LPS. Subsequently AVP and cortisol plasma levels rose in febrile animals, irrespective of hypothalamic heating and cooling, presumably as a consequence of pyrogenic activation of corticotropin releasing factor (CRF) producing neurons and their reciprocal interaction with TRH neurons on the one hand, and by a reciprocal interaction of the latter with AVP neurons on the other.

Animals↗
PubMed1996

Angiotensin II receptor subtypes in the duck subfornical organ: an electrophysiological and receptor autoradiographic investigation.

The pharmacology of angiotensin II (AngII) receptors was investigated in the brain of ducks using receptor autoradiographic and electrophysiological methods. Using 125I[Val5]AngII as a ligand, specific binding was observed in sections of the duck adrenal gland and in several brain areas involved in body fluid homeostasis. Displacement studies using the same antagonists as used for classifying mammalian AngII receptor subtypes revealed that the rank order of potencies in competition with AngII receptors in the adrenal gland and in the subfornical organ was: AngII > CGP-42112A > losartan > PD-123319. Electrophysiological recordings from spontaneously active neurons of duck SFO slices revealed that the majority of neurons could be excited by AngII (10(-7) M). The excitatory effect of AngII could be partially inhibited by CGP-42112A (10(-5) M), which proved to be more effective than equimolar losartan and far more effective than PD-123319. These data suggest that the neuronal AngII receptors in the SFO are pharmacologically distinct from the mammalian AT1- and AT2-receptors. Further, central AngII receptors of ducks share common pharmacological characteristics with AngII receptors in the duck adrenal gland and peripheral organs of other bird species.

Angiotensin II↗
PubMed1996

Effects of angiotensin II and its blockers Sar1-Ile8-angiotensin II and DuP 753 on drinking in ducks in relation to properties of subfornical organ neurons.

Properties of systemically applied angiotensin II in stimulating water intake of normally hydrated ducks were studied and the results compared with properties of angiotensin II-responsive neurons of the subfornical organ which are considered as targets for circulating angiotensin II acting as a dipsogen. Following intravenous infusion of hypertonic saline (2000 mosmol.kg-1 at 0.3 ml.min-1 for 1 h), intravenous infusion of 0.3 ml.min-1 isotonic saline with angiotensin II (200 ng.min-1), starting 1 h later, stimulated drinking in each case at an angiotensin II plasma level of about 1400 pg.ml-1. Without hypertonic priming, the same angiotensin II infusion did not stimulate drinking in each experiment; however, if effective, repeated infusions of ANGII induced stable dipsogenic responses. Angiotensin II infusions did not alter plasma levels of antidiuretic hormone. Sar1-Ile8-angiotensin II, a non-selective angiotensin II antagonist, acted weakly as a partial agonist when infused at a dose 200-fold higher than angiotensin II and effectively blocked the dipsogenic action of angiotensin II; this corresponds to the inhibition of angiotensin II-induced excitation by Sar1-Ile8-angiotensin II observed in duck subfornical organ neurons. DuP 753 (losartan), an angiotensin II antagonist specifically blocking AT1 receptors in mammals, had equivocal effects on angiotensin II-induced drinking in ducks at rates 50- and 200-fold higher than angiotensin II, which corresponds to the weak inhibitory action of this compound on angiotensin II-induced neuronal excitation in the duck SFO. Blood pressure was only marginally elevated by the applied angiotensin II dose and Sar1-Ile8-angiotensin II had no effect.

Angiotensin II↗
PubMed1996

Vasotocin acts as a dipsogen in ducks at concentrations stimulating subfornical organ neurons in vitro.

The effects of systemic infusions of the avian antidiuretic hormone arginine vasotocin on water intake of domestic ducks were investigated under steady conditions of water balance in which angiotensin II was effective as a dipsogen. The study proceeded from the consistent stimulatory effect of arginine vasotocin on angiotensin II-responsive neurons found in the subfornical organ of ducks, suggesting brain-intrinsic vasotocinergic control of these neurons which are also accessible to circulating agents because of the lacking blood-brain barrier. Levels of circulating arginine vasotocin of about 2700 pg.ml-1 which were close to the threshold for activation of subfornical organ neurons in vitro, induced weak but significant drinking responses. Even at this high arginine vasotocin level circulatory effects were absent, thereby excluding their interference with water intake. Arginine vasotocin plasma levels of about 60 pg.ml-1 significantly attenuated the dipsogenic action of angiotensin. While drinking in response to high pharmacological levels of arginine vasotocin is assumed to mimic a stimulatory innervation of angiotensin-responsive subfornical organ neurons by brain-intrinsic vasotocinergic axons, attenuation of angiotensin-induced drinking by high physiological arginine vasotocin levels cannot be explained by its action on central neurons, but may be secondary to body fluid retention caused by the antidiuretic action of arginine vasotocin.

Angiotensin II↗
PubMed1996

Opioid receptor imaging and displacement studies with [6-O-[11C] methyl]buprenorphine in baboon brain.

Buprenorphine (BPN) is a mixed opiate agonist-antagonist used as an analgesic and in the treatment of opiate addiction. We have used [6-O-[11C]methyl]buprenorphine ([11C]BPN) to measure the regional distribution in baboon brain, the test-retest stability of repeated studies in the same animal, the displacement of the labeled drug by naloxone in vivo, and the tissue distribution in mice. The regional distribution of radioactivity in baboon brain determined with PET was striatum > thalamus > cingulate gyrus > frontal cortex > parietal cortex > occipital cortex > cerebellum. This distribution corresponded to opiate receptor density and to previously published data (37). The tracer uptake in adult female baboons showed no significant variation in serial scans in the same baboon with no intervention in the same scanning session. HPLC analysis of baboon plasma showed the presence of labeled metabolites with 92% +/- 2.2% and 43% +/- 14.4% of the intact tracer remaining at 5 and 30 min, respectively. Naloxone, an opiate receptor antagonist, administered 30-40 min after tracer injection at a dose of 1.0 mg/kg i.v., reduced [11C]BPN binding in thalamus, striatum, cingulate gyrus, and frontal cortex to values 0.25 to 0.60 of that with no intervention. There were minimal (< 15%) effects on cerebellum. Naloxone treatment significantly reduced the slope of the Patlak plot in receptor-containing regions. These results demonstrate that [11C]BPN can be displaced by naloxone in vivo, and they affirm the feasibility of using this tracer and displacement methodology for short-term kinetics studies with PET. Mouse tissue distribution data were used to estimate the radiation dosimetry to humans. The critical organ was the small intestine, with a radiation dose estimate to humans of 117 nrad/mCi.

Animals↗
PubMed1996

Detection of anti-HIV-1 IgG antibodies in whole saliva by GACELISA and Western blot assays.

The present study, based on 158 HIV seropositives and 167 HIV seronegatives, demonstrates that saliva collected with the Omni-SAL device and tested with GACELISA (an IgG antibody capture ELISA) is an effective non-invasive alternative to serum for anti-HIV IgG antibody screening. The study also shows that a conventional serum Western blot kit can be used, with slight modifications, for confirmatory testing of saliva specimens. Collecting saliva with the Omni-SAL device had a very good acceptance rate among Tanzanian subjects, and although this diagnostic method is not yet known by the general public, 65% of the study participants preferred to give saliva instead of blood for HIV testing.

Adult↗
PubMed1996

Biotypes of oral Candida albicans isolates in a Tanzanian child population.

Although biotypes of Candida albicans from adult populations, especially in the West, have been described, there are no data either from a child population, or from the African continent. Hence a total of 200 oral C. albicans isolates from Tanzanian children aged 6-24 months were biotyped using two commercially available API micromethod kit systems and a boric acid resistance test. The predominant biotypes, which comprised two thirds of the organisms isolated, were J1S (19.5%), A1S (16.0%), J1R (14.5%), A1R (9.5%) and P1R (7.5%). In total, 16 new biotypes comprising 44 (22%) isolates which have not hitherto been described were found in this Tanzanian population and, of these, the P1R biotype predominated with 15 (7.5%) isolates. There was no significant association between predominant biotypes (with clusters > or = 15 isolates) and age, gender, breast feeding and malnutrition. These data indicate that the biotype profile of C. albicans isolates may differ in paediatric and adult populations, and/or global distribution of various subtypes of this common opportunistic pathogen.

Candida albicans↗
PubMed1995

Opposite effects of angiotensin II and nitric oxide on neurons in the duck subfornical organ.

Angiotensin II (ANGII) is known to activate neurons in the subfornical organ (SFO) of mammals and birds and this activation is regarded as the basis for the ANGII induced increase in water intake. Application of the nitric oxide (NO) donor sodium nitroprusside inhibited the activity in 10 out of 12 duck SFO neurons, 8 of which were in addition excited by ANGII. These data, in combination with the histochemical detection of NO synthase in the duck SFO, demonstrate the involvement of NO in SFO mediated responses and might represent the cellular basis for the observed opposite effects of ANGII and NO on water intake.

Angiotensin II↗
PubMed1995

Excitatory action of the bird antidiuretic hormone vasotocin on neurons in the subfornical organ.

The responsiveness of spontaneously active neurons in the subfornical organ (SFO) of adult ducks to angiotensin II (ANGII) and the bird specific antidiuretic hormone, arginine vasotocin (AVT), the analog of the mammalian arginine vasopressin (AVP), were investigated in brain slices with extracellular recording technique. 65% (n = 66) of the neurons increased their activity after superfusion with ANGII, the rest were unresponsive. Application of AVT activated 52% (n = 68) of the investigated neurons and like ANGII never caused an inhibition of the spontaneously active SFO neurons. A close correlation exists between the ANGII and AVT sensitivity of duck SFO neurons, because 29 out of 33 neurons were excited by AVT as well as ANGII. The relatively weak antagonistic effect of the V1-type receptor antagonist Pmp-Tyr (Me)-Arg8-vasopressin on the AVT induced excitation suggests a different pharmacology of the bird AVT receptor as compared to the mammalian AVP receptor. The excitatory response of ANGII and AVT on the very same neurons suggest a similar function of both peptides on SFO mediated effects in vivo, such as an increase in water intake. However, peripheral AVT concentrations, unlike ANGII concentrations in the blood are not high enough to activate SFO neurons from the blood side of the blood brain barrier. Therefore AVT is presumably released from synapses of neurons originating within or projecting to the SFO. The identity of the ANGII and AVT reactive neurons suggests that synaptically released AVT should facilitate SFO mediated drinking.

Angiotensin II↗
PubMed1995

The effect of a cervical collar on the tidal volume of anaesthetised adult patients.

Semi-rigid cervical collars may be used to assist the stabilisation of the cervical spine during transport in patients suffering from major trauma. We have attempted to evaluate the effect of one such collar on airway patency in the presence of depressed airway reflexes. Thirty-eight patients undergoing anaesthesia via face mask with spontaneous ventilation were studied. Tidal volume was measured with the airway in three different positions, both with and without a collar. The collar made no statistically significant difference to tidal volume in any position. Changing support of the airway increased tidal volume both with and without the collar. Patients fitted with an incorrectly sized collar may develop upper airway obstruction in the presence of impaired consciousness. Experience should be gained in the correct fitting of semi-rigid collars.

Adolescent↗
PubMed1995

Association between carriage of oral yeasts and malnutrition among Tanzanian infants aged 6-24 months.

OBJECTIVE: To determine if there is an association between carriage of oral yeasts and malnutrition in infants. DESIGN: A case-control study within a cross-sectional study. The dependent variable was carriage of oral yeasts. The exposure variable was malnutrition and confounders to be adjusted for were age, sex, and breast-feeding. SETTING: A maternal and child health clinic in Dar-es-Salaam, Tanzania that offers routine medical check-ups to all expectant mothers and children aged between 0 and 5 years in its catchment areas. SUBJECTS AND METHODS: 972 infants aged 6-24 months participated. Smears from the tongue and cheek mucosa were examined for candidal hyphae and blastospores. Malnutrition was categorized according to Tanzanian standards (weight-for-age) and World Health Organization (WHO) standards (weight-for-height and height-for-age). MAIN OUTCOME MEASURE: Carriage of oral yeasts (hyphae and blastospores). RESULTS: Carriage of oral yeasts was significantly higher in the 227 malnourished compared with the 745 well nourished adjusted for confounders. Odds ratio for presence of hyphae in smears from the severely malnourished (weight-for-age) was 4.5 (90% CI: 2.0-10.0). Odds ratio for presence of hyphae was 2.3 (90% CI: 1.1-4.8) when weight-for-height were used to categorize for malnutrition. CONCLUSION: The study tends to confirm the generally held view that malnutrition may predispose to carriage of oral yeasts and subsequent oral candidiasis.

Candida↗
PubMed1995

Saliva and salivary gland alterations in HIV infection: a review.

HIV-1 can be recovered sporadically from whole saliva and individual salivary gland secretions, but the concentration of virus, when present, is low. Saliva possesses antiviral activity, and although virus may be found in the mouth, the mouth is not a transmission route of HIV-1. After HIV-1 infection, salivary gland function is altered. Flow rates may decrease, and certain electrolytes and anti-microbial proteins are elevated. A proportion of patients develop severe salivary gland disease. Most patients, however, maintain adequate salivary gland function and retain ability to produce antimicrobial proteins in saliva.

Antiviral Agents↗
PubMed1994

Noradrenergic modulation of avian kidney function.

Norepinephrine (NE) infused at doses of 0.7, 2.2 and 6.7 micrograms/min/kg body weight into conscious, salt and water loaded ducks dose-dependently induced arterial hypertension, reflex bradycardia and diuresis/natriuresis at unchanged glomerular filtration and reduced renal blood flow. NE-induced changes in plasma concentrations of osmoregulatory hormones consisted of a slight increase for the antidiuretic hormone, no change for angiotensin II and a nearly 4-fold increase for atrial natriuretic factor. Sub-pressor doses of NE infused close to the origin of the renal arteries induced diuresis without a rise in urinary sodium concentration. The results suggest pressure diuresis in ducks as a response to hypertensive NE doses with a possible contribution of atrial natriuretic factor to natriuresis.

Angiotensin II↗
PubMed1994

Intact primary memory in mild to moderate Alzheimer disease: indices from the California Verbal Learning Test.

The California Verbal Learning Test (CVLT; Delis, Kramer, Kaplan, & Ober, 1987) was administered to patients with mild to moderate Alzheimer disease (AD) (Group AD; n = 13) and to a control group of normal older adults (Group NC; n = 13) matched on age and education. Two measures were used to determine whether primary memory (PM) is impaired in early AD. One measure, considered a relatively "pure" measure of PM, is based on the procedure developed by Tulving and Colotla (1970) which considers an item to be recalled from PM if no more than six items intervene between its presentation and recall. The other measure is the more commonly used recall from recency. No significant difference between the AD and NC Groups was found, both on the Tulving and Colotla measure, as well as on the recall from recency measure of PM. A significant difference was obtained on two measures of secondary memory (SM), namely, Tulving and Colotla's measure and recall from the primacy and middle regions of the list of words. In comparison to NC, and AD patients showed little evidence of learning over the five trials, and poor retention even over short delays. In addition, the patients with AD showed deficits in clustering words by taxonomic category at recall. We conclude that impairment in PM cannot be used as a diagnostic marker of AD in the early stages of the disease process.

Aged↗
PubMed1994

Hypothalamic thermal stimulation modulates vasopressin release in hyperosmotically stimulated rabbits.

Under thermoneutral conditions conscious rabbits received systemic infusions of NaCl as hypertonic solution (90 mueq.min-1.kg body wt-1), which raised their plasma osmolality from 283 to 312 mosmol/kgH2O. Rabbits receiving isotonic saline served as controls. Hypertonic stimulation induced a 60% reduction of both respiratory frequency and evaporative water loss. Rectal temperature rose by 0.4 degrees C despite enhanced peripheral vasodilation as indicated by increased ear skin temperature. Plasma vasopressin (AVP), aldosterone (ALDO), and corticosterone (COR) were significantly elevated from 6 to 16 pg/ml, 90 to 180 pg/ml, and 17 to 40 ng/ml, respectively. To elucidate the importance of central temperature for AVP and adrenal corticosteroid release, hypothalamic thermal stimulations (20 min) were superimposed during established iso- and hyperosmotic steady-state conditions. Different from isosmotic controls, hyperosmotic animals responded to hypothalamic cooling (37 degrees C) with a significant decrease in plasma AVP from 16 to 13 pg/ml and to hypothalamic warming (41 degrees C) with a significant rise from 16 to 19 pg/ml. A weak temperature effect on COR release was also disclosed, especially of hypothalamic cooling, which significantly lowered plasma COR from 42 to 34 ng/ml. These results provide evidence for positive local temperature coefficients of hypothalamic control of AVP release and suggest a similar property also for the control of COR release by the hypothalamo-adenohypophysial axis.

Aldosterone↗
PubMed1993

[Complex evaluation of risk factors in patients after myocardial infarction]].

In this work the authors have constructed a clinical epidemiological score system for characterizing the severity of the diseased state of our 85 patients got over myocardial infarction. The important role is commonly known which is played by the free radical processes in the pathogenesis of the heart infarct. From these free radical reactions the authors have focused their attention to studying the lipid peroxides. Beside the determinations of the malondialdehyde content of native serums they have measured the intensity of the malondialdehyde development in the free radical system generated by hydrogen-peroxide in vitro treatment of serums. With the help of the newly elaborated and applied method they have obtained a 67.11% average increase of the amount of malondialdehyde developed in vitro in comparison with the mean malondialdehyde value measured in the same analytical conditions with 154 healthy controls. They have made a statistical calculation for studying the question if there is any relationship between the scores of the age of patients and the malondialdehyde values of hydrogen-peroxide treated serums. On the basis of results of biochemical measurements and statistical analyses it seems very important to pay more attention both to the intensity of free radical reactions and the patients age in the severity's relations of the diseased state at heart infarct patients.

Adolescent↗