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A Glatt

Publications and source records attributed to A Glatt.

At least 19 recordsLinked to original sources
PubMed2002

Rapid detection of methicillin-resistant staphylococci from blood culture bottles by using a multiplex PCR assay.

Rapid detection and accurate identification of methicillin-resistant staphylococci are critical for the effective management of infections caused by these organisms. We describe a multiplex PCR-based assay for the direct detection of methicillin-resistant staphylococci from blood culture bottles (BacT/Alert; Organon-Teknika, Durham, N.C.). A simple lysis method followed by a multiplex PCR assay designed to detect the nuc, mecA, and bacterial 16S rRNA genes was performed. A total of 306 blood culture specimens were collected over a period of 10 months from June 1998 to April 1999, consisting of 236 blood cultures growing staphylococci (including 124 methicillin-resistant Staphylococcus spp.), 50 positive blood cultures which grew organisms other than staphylococci, and 20 blood cultures that were negative for bacterial and fungal pathogens after 5 days of incubation and terminal subculture. DNA extraction, PCR, and detection could be completed in 2.5 h. Of the positive blood cultures with staphylococci, the multiplex PCR assay had a sensitivity and specificity of 99.2% and 100%, respectively. Our results show that rapid, direct detection of methicillin-resistant staphylococci is possible, allowing clinicians to make prompt and effective decisions for the management of patients with staphylococcal bacteremia.

Bacteremia↗
PubMed2001

Molecular epidemiology of tuberculosis among eight hospitals in New York City, 1996-1997.

OBJECTIVE: To determine the molecular epidemiology of tuberculosis isolated from patients cared for at eight hospitals scattered throughout New York City. MATERIALS AND METHODS: Cases of tuberculosis occurring in 1996 and 1997 at collaborating hospitals were identified, and demographic data were extracted from patient charts. All available isolates were analyzed by IS6110 for genetic relatedness. The molecular fingerprints were compared both to each other and to the larger repository of strains from New York City developed and maintained at the Public Health Research Institute. RESULTS: One hundred and eighty cases were fully characterized. Compared with New York City cases, study patients were more likely to be Asian and less likely to be non-Hispanic blacks. Overall, 97 (54%) of the cases were clustered with respect to other study strains or with respect to the other New York City isolates. Clustered strains were significantly more likely to be from non-Hispanic blacks or patients born in the United States. The largest cluster (n = 17) was the "W" strain previously associated with an outbreak of multidrug-resistant tuberculosis in New York City. In the current study, the majority of W strain isolates were fully drug-susceptible. CONCLUSIONS: High rates of genetically related tuberculosis continue to occur among patients in New York City, in spite of improved control of nosocomial outbreaks and dramatic decreases in the overall case rates. The use of molecular techniques to suggest patterns of transmission has become essential in developing and assessing routine tuberculosis control strategies.

Adult↗
PubMed1997

Tuberculosis among foreign-born persons in New York City, 1992-1994: implications for tuberculosis control.

OBJECTIVE: To study the pattern of transmission of tuberculosis (TB) among foreign-born persons living in New York City. DESIGN: A retrospective multicenter study comparing 158 foreign-born patients to 231 US-born patients diagnosed with TB between 1992 and 1994. The patients were stratified according to their Mycobacterium tuberculosis isolate DNA fingerprint patterns. RESULTS: Nineteen (16%) of 122 isolates from foreign-born TB patients and 75 (42%) of 180 isolates from US-born TB patients had DNA fingerprint patterns (cluster patterns) indicative of recent exogenous transmission (P < 0.001). All cluster pattern strains from foreign-born cases were identical to those found among US-born patients. The likelihood of infection with a cluster pattern strain among foreign-born persons increased with duration of residence in the US, and was significantly associated with being homeless (P < 0.05), or having multidrug-resistant TB (P = 0.00072). CONCLUSION: Although most (84%) cases of TB among foreign-born persons in New York City appear to result from reactivation of infections they acquired abroad, the ones who acquire new infections become infected with strains that are already circulating among the US-born TB patients in New York City, and they have risk factors similar to those faced by US-born tuberculosis patients.

Adult↗
PubMed1993

Brofaromine: a monoamine oxidase-A and serotonin uptake inhibitor.

Brofaromine is a tight-binding, reversible inhibitor of monoamine oxidase-A (MAO-A), with concomitant serotonin (5-HT) uptake-inhibiting properties. In psychopharmacologic investigations, the compound shows the properties expected of an MAO inhibitor, antagonizing the effects of reserpine, tetrabenazine, and 5-hydroxytryptophan in rats and mice, and suppressing rapid eye movement sleep in cats. Brofaromine showed antidepressant-like activity in a rat social conflict test. In radioligand binding assays, brofaromine exhibited weak or no interaction with alpha 1- and alpha 2-noradrenergic, 5-HT1, 5-HT2, 5-HT3, cholinergic, histamine H1 and H2, mu-opiate, GABAA, benzodiazepine, adenosine, neurotensin, and substance P receptors. Comparison of in vitro and in vivo potencies to inhibit 5-HT uptake with those of reference drugs, and direct evidence in patients and volunteers suggest that 5-HT uptake inhibition plays a role in the clinical profile of brofaromine.

Animals↗
PubMed1992

The time course of sigma activity and slow-wave activity during NREMS in cortical and thalamic EEG of the cat during baseline and after 12 hours of wakefulness.

The extrapolation from recent neurophysiological findings concerning the dependency of spindle and slow-wave oscillations of thalamocortical neurons on membrane potential to macroscopic EEG events, predicts a reciprocal relation between spindle activity and slow-wave activity (SWA) in thalamic and cortical EEG during non-rapid-eye-movement sleep (NREMS). To test this hypothesis, the EEG recorded in 8 cats, from the nucleus centralis lateralis of the thalamus and from the skull during a 12-h baseline dark period and during a 12-h recovery dark period, following a 12-h sleep deprivation, were analyzed. Per 12-s epoch, sleep-wake behaviour was determined and spectral power density was computed in the slow-wave frequency range (0.5-4.0 Hz) and in the spindle frequency region (sigma activity: 11.0-14.5 Hz). To analyze the development of EEG power densities in the course of NREMS and during the transition from NREMS to REMS, the last epoch of wakefulness and the first 15 epochs of NREMS, as well as the last epochs of NREMS and the first epoch of REMS were selected from the NREM-REM cycles. For each animal the values were averaged over 4-h intervals. In the cortical EEG, SWA was minimal at NREMS onset and increased progressively in the course of NREMS. SWA declined sharply prior to REMS. sigma Activity increased gradually towards a uniform level after NREMS onset. During the transition to REMS, sigma activity initially increased and then decreased rapidly. In the thalamic EEG, the time course of SWA paralleled that of the cortex. However, the development of sigma activity during the first part of NREMS differed: in the thalamic EEG, sigma activity was maximal during the beginning of NREMS and slightly decreased thereafter. After sleep deprivation, SWA within NREMS was markedly enhanced in both the cortical and the thalamic EEG. Sigma activity was attenuated in the thalamic EEG, whereas in the cortical EEG it was temporarily elevated. The present data show that, in the thalamic EEG, an inverse relation exists between spindle and slow-wave activity during baseline NREMS. This relation is preserved after sleep deprivation. In the cortical EEG, a reciprocal relation between spindling and SWA is less evident.

Animals↗
PubMed1992

CGS 5649 B, a new compound, reverses age-related cognitive dysfunctions in rats.

CGS 5649 B improves the learning performance of aged rats in a one-way active-avoidance situation. If, under reversed conditions, treated aged rats are also tested for passive avoidance, they show "place learning," which our findings have demonstrated to be typical of young rats. The effects of the substance are not confined to these experimental models nor are they species specific: it also facilitates passive avoidance in mice and social learning in rats. The compound is effective if administered before or immediately after the learning trial.

Aging↗
PubMed1992

Enhanced slow-wave activity within NREM sleep in the cortical and subcortical EEG of the cat after sleep deprivation.

Electroencephalograms (EEGs) of the cortex and of seven subcortical structures were recorded during two baseline days and during a recovery day following a 12-hour period of sleep deprivation (SD) in eight cats. The EEGs were analyzed by visual scoring and by spectral analysis. The following subcortical structures were studied: hippocampus, amygdala, hypothalamus, nucleus centralis lateralis of the thalamus, septum, nucleus caudatus and substantia nigra. The EEGs of all brain structures exhibited sleep state-dependent changes. In general, slow-wave activity (SWA, 0.5-4.0 Hz) during nonrapid eye movement (NREM) sleep exceeded that of REM sleep. The power spectra (0.5-24.5 Hz) in NREM, as well as the relationship between the power spectra of NREM and REM sleep, differed between the recording sites. Moreover, the rate of increase of SWA in the course of an NREM episode and the rate of decrease of SWA at the transition from NREM to REM sleep differed between the brain structures. During the first 12 hours following SD, the duration of NREM increased due to a prolongation of the NREM episodes. REM increased by a rise in the number of REM episodes. During the same period, the NREM EEG power density in the delta and theta frequencies was enhanced in all brain structures. Furthermore, in all structures the enhancement of SWA was most pronounced at the beginning of the recovery period and gradually declined thereafter. SD also induced a rise in the rate of increase of SWA in the NREM episodes in all recording sites. This indicates that the enhancement of EEG power density was not only due to prolongation of the NREM episodes. The EEG activity during REM was barely affected by the SD. It is concluded that, in all brain structures studied, the EEG during NREM is characterized by high levels of SWA. Furthermore, in each brain structure, SWA within NREM sleep is enhanced after a prolonged vigil. These data may indicate that SWA reflects a recovery process in cortical and subcortical structures.

Animals↗
PubMed1991

Effects of circadian phase and duration of sleep deprivation on sleep and EEG power spectra in the cat.

The electroencephalogram (EEG) of cats was recorded under baseline conditions (LD 12:12) and after 4 and 8 h of sleep deprivation (SD). The EEG was analyzed by visual scoring and by spectral analysis. Under baseline conditions the 24-h distribution of sleep was bimodal: the smallest amounts of sleep occurred at the light-dark and dark-light transitions. EEG slow-wave activity (power density in the delta frequency range: 0.5-4.0 Hz) in non-rapid-eye-movement sleep (NREMS) showed a small variation over the 24-h period. When recovery sleep, following 4 h and 8 h of SD, started at the beginning of the dark period, no significant rebound of NREMS and REMS occurred during the 24-h recovery period. When recovery sleep, after 4 h of SD, started at the fifth hour of the light period, the amount of NREMS was increased. In all experiments the EEG power density in NREMS was enhanced after SD in the entire frequency range studied (0.5-31.5 Hz), but more prominently in the delta and theta (4.5-7.0 Hz) frequency bands. The effects dissipated in the course of the recovery period. The magnitude and duration of the enhancements of EEG power densities were dependent on the duration of SD and on the circadian phase at which SD was scheduled. It is concluded that in the cat sleep is a function of both circadian and homeostatic processes and that especially the EEG power density in NREMS is highly responsive to sleep loss.

Analysis of Variance↗
PubMed1989

Spontaneous motor activity in healthy volunteers after single doses of haloperidol.

Video recordings of the spontaneous motor activity of 6 healthy volunteers after treatment with 0.75 mg haloperidol i.v., or placebo, were transcribed into a time-series protocol of motor behaviour. Characteristic changes seen after the injection of haloperidol consisted in a reduction of the motility of the extremities and prolongation of the phases of both movement and immobility of the head. The tested dose of haloperidol induced a distinct rise in serum prolactin and sedation, but had no effects on the pharmaco-EEG or on the critical flicker-fusion frequency. Analysis of the motor phenomena evoked by neuroleptics in healthy persons and in patients may help, on the other hand, to establish correlations with the motor effects observable in preclinical investigations in animals and might also contribute towards the elucidation of the extrapyramidal side-effects of these drugs.

Adult↗
PubMed1988

Antimicrobial agents.

Explore the source record for details and available documents.

Drug Administration Schedule↗
PubMed1987

Cholinomimetics induce theta rhythm and reduce hippocampal pyramidal cell excitability.

The actions of cholinomimetics and of physostigmine were tested on two parameters reflecting hippocampal activity, namely theta activity and pyramidal cell excitability. In rats pretreated with methylscopolamine and anaesthetized with urethane i.v. administration of the cholinomimetics oxotremorine and arecoline and the cholinesterase blocker physostigmine evoked theta wave activity in the hippocampus, which was blocked by scopolamine. Spectral analysis demonstrated that the frequency of the theta waves induced was dose-related, ranging from about 3 Hz to between 5 and 6 Hz. theta Activity could not be induced by arecoline in animals with large septal lesions. Pyramidal cell excitability is known to be increased by endogenous acetylcholine released from cholinergic fibres. In the present study, however, i.v. injections of oxotremorine, arecoline and physostigmine in doses that induce theta activity diminished the excitability of CA1 pyramidal cells in a dose-dependent manner, as judged by the reduction in the amplitude of the population spike and the dendritic epsp. These depressant effects were attenuated by scopolamine but not by methylscopolamine. The depressant effect of arecoline was attenuated in rats with extensive lesions in the medial septal area. The present findings demonstrate that exogenously administered cholinomimetics only partly mimic the action of endogenous acetylcholine in the hippocampus. The central sites of action of exogenously administered cholinomimetics for mediation of theta activity and alteration of pyramidal cell excitability remain to be elucidated.

Acetylcholinesterase↗
PubMed1986

Behavioral effects and general pharmacology of 4-(5-chloro-benzofuranyl-2)-1-methylpiperidine HC1, an antidepressant inhibiting both monoamine oxidase A and 5-hydroxytryptamine uptake.

In psychopharmacological tests in rats and mice, 4-(5-chloro-benzofuranyl-2)-1-methylpiperidine HC1 (CGP 4718 A) was found to exert behavioral effects typical of both monoamine oxidase (MAO)-A and 5-hydroxytryptamine (5-HT) uptake inhibitors (reserpine antagonism, L-5-HTP potentiation, antiaggressive activity in isolated mice). The potential antidepressant activity of the drug was indicated in rats by antagonism of reserpine and its effect in the social-conflict test. CGP 4718 A did not impair motor coordination and had no influence on locomotor activity up to high doses in mice and rats. In monkeys, it increased directed individual activities, including sex-related behaviors and diminished locomotor activity and passivity. Electroencephalographic studies in cats revealed a significant decrease in paradoxical sleep after treatment with CGP 4718 A. In isolated organs, no significant antagonism of norepinephrine, 5-HT, acetylcholine or histamine was found. Cardiovascular studies in cats showed only transient effects on blood pressure and no effect on heart rate. In conscious dogs no cardiovascular effects were found. No potentiation of the pressor effect of tyramine in rats was detectable after repeated doses of up to 300 mg/kg p.o. A weak cardiodepressant effect was seen in isolated guinea pig atria. In conclusion, in animal experiments CGP 4718 A combines an interesting spectrum of antidepressant, activating and antiaggressive properties with a lack of cardiovascular and tyramine-potentiating effects.

Animals↗
PubMed1983

EEG evaluation of drug effects in the rat.

A test procedure, inducing a defined state of vigilance in rats, has been investigated to ascertain its usefulness for EEG monitoring of the effects of drugs. In order to prevent spontaneous fluctuations in the level of vigilance, rats were trained to walk in a slowly rotating treadwheel. The level of vigilance recorded under these conditions could be shifted by amphetamine, 1.0 mg/kg p.o., to a higher state of arousal, as shown by a reduction in power in all frequency bands, and by diazepam, 0.3 mg/kg p.o., to a lower state of arousal, as indicated by a rise in the activity at low frequencies. Imipramine (1.0, 3.0 and 10.0 mg/kg p.o.) caused a dose-related reduction in power in the intermediate frequency bands (3-18 Hz).

Amphetamine↗
PubMed1981

Quantification of slow-wave EEG induced by atropine: effects of physostigmine, amphetamine and haloperidol.

The goal of this study was to investigate whether the atropine-induced slow waves in the rat EEG could be easily quantified and used to assess the action of drugs on the central cholinergic systems manifested at the cortical level. Cable-transmitted EEG recordings were made in freely-moving male rats over periods of 5-6 h. Visual inspection of the EEG led us to divide it into 2 states, according to frequency and amplitude criteria: desynchronized, low voltage activity was termed 'State 1', also including other arousal patterns like 'theta spindles'. Slow-wave, high voltage activity, as well as faster patterns like spindles of slow-wave sleep, were included in 'State 2'. The time spent in State 2 (chosen because slow waves are admittedly increased by atropine) was visually determined on the EEG paper tracings. Atropine per se, at increasing doses, (1, 3, 10, 30 and 100 mg/kg i.p.), induced an increased duration of State 2. By contrast, physostigmine per se at doses of 0.01, 0.1 and 0.3 mg/kg i.p. reduced this duration with increasing doses. The atropine (10 mg/kg i.p.)-induced increase of State 2 was markedly attenuated by physostigmine (0.1 and 0.3 mg/kg i.p.) and amphetamine (1 mg/kg i.p.), but potentiated by haloperidol (0.3 mg/kg i.p.). The effects of the different drugs and combinations on the general behavior were also noted. In conclusion, this approach appears to present a promising tool for the study of the interaction of drugs with central cholinergic systems.

Amphetamine↗
PubMed1980

Some electrophysiological and pharmacological properties of the cortical, noradrenergic projection of the locus coeruleus in the rat.

The effect of repetitive stimulation of the locus coeruleus (LC) on the discharge rate of spontaneously active neurons of the visual, rostral and cingulate cortex was investigated in untreated and catecholamine-depleted rats under chloral hydrate anesthesia. In untreated animals, the inhibitory transsynaptic effects predominated over the excitatory ones. In catecholamine-depleted rats, the percentage of inhibited cells was significantly reducted in all areas. The vast majority of spontaneously active neurons in all cortical regions was depressed by microiontophoretically applied noradrenaline (NA). A few cells were resistant to NA; no excitatory effects were noticed on any cell. The transsynaptically mediated depression of the discharge rate of cells in all three cortical areas was reversibly antagonized by the iontophoretically administered beta-receptor blocking drug practolol. On the contrary the a-receptor blocking drugs piperoxane and WB4101 were ineffective in this respect. Thus, we tentatively conclude from these data that the NA-elicited depression of cells in the cortex is mediated by a receptor of the beta-type. Repetitive stimulation of the reticular formation elicited a desynchronizing effect on the EEG of chloral hydrate anaesthetized rats. LC stimulation, in contrast, hardly produced any modification of the EEG as judged by visual examination of the recordings.

Adrenergic alpha-Antagonists↗