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J Svenson

Publications and source records attributed to J Svenson.

12 recordsLinked to original sources
PubMed1999

Non-specific effect of naltrexone on ethanol consumption in social drinkers.

RATIONALE: Clinical studies have shown that the opioid antagonist naltrexone is effective in the treatment of alcoholism. However, the mechanism by which it produces this effect is not understood. OBJECTIVE: This study was designed to investigate the effect of acute naltrexone on consumption of ethanol in healthy, non-problem social drinkers. METHODS: Subjects (n=24) participated in an eight-session, within-subject, placebo-controlled choice procedure which measured ethanol preference and consumption. The procedure consisted of two blocks of four sessions in which subjects received either naltrexone (50 mg oral) or placebo 1 h before consuming an ethanol or placebo beverage. On the first two sessions of each block, subjects received a color-coded beverage containing ethanol (0.75 g/kg) or placebo, in five equal portions at 15-min intervals. On the next two sessions of each block, subjects chose which beverage they preferred (i.e., placebo or ethanol) and how much they wished to take, in unit doses (placebo or ethanol 0.15 g/kg/dose). The primary behavioral measures were (1) the number of times subjects chose ethanol over placebo, and (2) the number of doses they consumed. Subjects rated their mood states and subjective drug effects at regular intervals during each session. RESULTS: Naltrexone did not alter the frequency of ethanol (versus placebo) choice. Although naltrexone did decrease the total number of ethanol doses subjects took (mean 2.7 doses after naltrexone; 3.4 doses after placebo), it also decreased the number of placebo "doses" subjects took on sessions when they chose the placebo beverage (mean 1.6 placebo doses after naltrexone; 2.8 doses after placebo). Ethanol produced its prototypic subjective effects (e.g., increased ratings of "feel drug", "like drug" and "high"), and these effects were not altered by naltrexone. Naltrexone produced mild sedative-like effects, and several subjects reported adverse effects such as nausea. CONCLUSIONS: These findings show that naltrexone reduces ethanol consumption in healthy volunteers, as it does in alcoholics. However, this reduction was not specific to alcohol; subjects also consumed less of a non-alcoholic, placebo beverage. These findings suggest that naltrexone may reduce alcohol consumption by a non-specific mechanism.

Adult↗
PubMed1998

Spectroscopic studies of the molecular imprinting self-assembly process.

A method for the rapid estimation of the extent of complex formation in molecular imprinting prepolymerization mixtures is described. By the use of a UV spectroscopy titration procedure, apparent binding constants for such self-assembly processes have been obtained. This method was used for comparison of the interactions between a dipeptide template (N-acetyl-L-phenylalaninyl-L-tryptophanyl methyl ester) and the functional monomer methacrylic acid, and the monomer analogues acetic acid and trifluoroacetic acid. The importance of template-monomer association during the molecular imprinting prepolymerization phase is discussed with respect to the systems studied.

Acetic Acid↗
PubMed1997

Competitive flow injection enzyme immunoassay for steroids using a post-column reaction technique.

Two types of flexible, sensitive and rapid competitive flow injection enzyme immunoassay were developed and evaluated for their potential use in the bioanalysis of steroids. Instead of the more typical approach where the signal is generated from antibody-bound hapten-enzyme conjugate, the non-bound fraction passing through the affinity column was allowed to react with an enzyme substrate from a merging channel in a post-column reaction system. The enzyme product (p-aminophenol or 4-methyl umbelliferol) was amperometrically or fluorometrically detected. Several parameters known to affect signal generation in the immunoassay were evaluated, including flow rate through the affinity column and through the reaction coil, the length of the reaction coil and of the affinity column. In the pre-incubation approach, where samples were mixed with enzyme conjugate and antibodies before injection, a sample throughput as high as 20 h(-1) was possible. The signal precision was about 1% (RSD) for cortisol (0.6-80 pmol) and 2% (RSD) for budesonide (0.02-12.5 pmol). In the displacement assay for cortisol, enzyme-labelled analyte was displaced from the affinity column when the sample was injected into the flow. A standard curve was obtained with a signal precision of 4-20% for 12.5-1250 pmol injected. The same instrumental set-up was used in both types of immunoassay, and thus a highly flexible system was obtained. A simple replacement of the affinity column from protein G in the pre-incubation approach to a column containing primary antibodies in the displacement assay was needed.

Budesonide↗
PubMed1997

Critical care of medical and surgical patients in the ED: length of stay and initiation of intensive care procedures.

Little is known about the extent of critical care delivered to patients in the emergency department (ED) and its impact on ED lengths of stay or patient outcomes. The purpose of this study was to characterize the timing of care for critically ill patients, both medical and surgical, in the ED. The design was a retrospective review. The setting was a university teaching hospital. The subjects were ED patients subsequently admitted to a medical or surgical intensive care unit (ICU). The average length of stay in the ED was 367 minutes. Thirty percent of patients were boarded in the ED because of lack of beds in the ICU. Stabilization procedures were performed on 45 (27%) patients, on average 102 minutes after ED admission. Monitoring procedures were performed on 35 (21%), on average 170 minutes after ED admission. There were no significant differences in length of stay, use, and timing of critical procedures in medical and surgical patients. Critically ill patients represent a significant portion of ED patients and may remain in the ED for prolonged periods of time. One of the major contributors to these prolonged stays are lack of beds. Both resuscitative and monitoring procedures are often performed in the ED setting for all types of critical patients. The timing of these procedures indicates that they are performed when necessary for patient care regardless of ED or ICU setting. Thus, ICU care is often initiated and maintained in the ED setting. EDs must be staffed adequately with appropriately trained personnel to care for these patients.

Bed Occupancy↗
PubMed1987

Obtundation in the elderly patient: presentation of a drug overdose.

The case of an obtunded elderly woman is presented. The patient initially was thought to have suffered a cardiovascular accident but was discovered to have taken an overdose of flurazepam hydrochloride. Depression is a common and under-recognized problem in the geriatric population. As a consequence, suicide rates are highest in the elderly. Over- and underdosing of both prescription and nonprescription drugs are common means available to the suicidal elderly patient. These overdoses are often attributed to unintentional patient errors and overlooked for what they are, attempted suicides, or they are missed entirely as a cause of the patient's presentation. This case illustrates the need to consider drug overdose in the obtunded elderly patient.

Aged↗
PubMedDate not supplied

Headache in the emergency department: importance of history in identifying secondary etiologies.

Headache is a common emergency department complaint and has a broad differential diagnosis. Most commonly the headache is without serious underlying cause, but occasionally can be the manifestation of a more catastrophic illness. History may be the most important aspect in the evaluation of headache patients and careful attention to historical clues or atypical symptoms may point to a diagnosis. We present a patient with a first-time headache, which was ultimately found to be secondary to a carotid cavernous fistula. Historical features that require a more aggressive work-up of headache are discussed.

Adult↗