Copper accumulation and metabolism in primary monolayer cultures of rat liver parenchymal cells.

The characteristics of hepatic copper accumulation and metabolism were studied using primary monolayer cultures of adult rat liver parenchymal cells. Accumulation of copper from serum-free medium was temperature dependent and strongly inhibited by cyanide and N-ethylmaleimide. Addition of various concentrations of zinc to the medium did not alter copper accumulation by the cells. Furthermore, it was found that supplementation of the cell cultures with dexamethasone significantly stimulated zinc accumulation without affecting the accumulation of copper. Cycloheximide substantially stimulated accumulation of copper from the culture medium, whereas actinomycin D had no effect. Effux experiments showed that copper is rapidly sequestered by intracellular components and becomes unavailable for exchange soon after it is transported into the cells. Gel chromatography of liver cytosol demonstrated that most of the copper that is initially accumulated is bound to the low molecular weight cytoplasmic protein metallothionein.

Liposome-collagen gel matrix: a novel sustained drug delivery system.

This report describes the properties of a novel sustained-release drug delivery system comprising liposomes sequestered in a collagen gel. Two peptide hormones, insulin and growth hormone encapsulated in vesicles sequestered within the matrix, are slowly released into the circulation from either an intramuscular or subcutaneous injection site. A maximum 3-5-d release for insulin or a 14-d growth hormone release was observed. Enhanced sequestration of liposomes with the collagen can be achieved by modifying the liposome surface with fibronectin. The liposome gel delivery system appears to offer several advantages over other liposome formulations or gel formulations constructed only with free drug.

A comparison of two bedside tests for the detection of salicylates in urine.

OBJECTIVE: Ferric chloride (FC) and Trinder reagent (TR) have both been used to identify salicylates (ASA) in the urine of patients presenting with possible drug overdose. The authors sought to compare the sensitivities and specificities of these two reagents in detecting ASA in the urine of patients presenting to an emergency department (ED) with suspected drug overdose. METHODS: Patients were eligible for inclusion in this study if they presented to the ED with either suspected overdose or unexplained metabolic acidosis. One milliliter of the patient's urine was added to 1 mL of each of the two reagents. A positive test was defined as any darkening of the color of the reagent. Each patient had a quantitative serum ASA measured. RESULTS: Twenty of 180 patients (11%) had quantitative serum ASA levels above 5 mg/dL. Both reagents were 100% sensitive in identifying these patients. The specificity of FC was 71% compared with 73% for TR. The two reagents gave similar results in 91% of cases. CONCLUSION: Both FC and TR are reliable in detecting ASA in the urine of patients presenting with suspected drug overdose. A negative result with either test eliminates the need for a quantitative serum ASA level. Because FC has a longer shelf life than TR, it is the more practical reagent for use in the ED.

Utilization of lumbosacral spine radiographs for the evaluation of low back pain in the emergency department.

We sought to determine how often Emergency Physicians (EPs) order plain radiographs (XRs) of the lumbosacral spine in evaluating patients with low back pain (LBP). In addition, we sought to determine what history and physical examination findings were statistically associated with the use of an XR. Patients evaluated in our Emergency Department (ED) between April 1, 1995 and September 30, 1995 for LBP were identified retrospectively by their ICD-9 discharge code. The ED record was reviewed, and an odds ratio (OR) was calculated for each of several history and physical examination findings, to determine which of them increased the likelihood of having an XR. Forty of 214 patients (19%) with LBP had an XR done. Patient characteristics associated with the use of an XR were: a positive straight leg examination, age > 50 years, a history of trauma, and vertebral tenderness. In this series, only a small minority of patients with LBP had an XR done as part of their ED evaluation. The choice of which patients to image was determined by history and physical examination findings. We conclude that the EPs we studied are evaluating LBP as conservatively, if not more so, than physicians in other specialties.

Ketamine abusers presenting to the emergency department: a case series.

Ketamine hydrochloride, familiar to emergency physicians as a dissociative anesthetic, has been abused as a hallucinogen for almost 30 years. The drug produces effects similar to those of phencyclidine but with a much shorter duration of effect. Since 1996, an increasing number of patients have presented to Connecticut Emergency Departments (EDs) after the intentional abuse of ketamine. Because the medical literature contains almost no information on the consequences of ketamine abuse, we have compiled a series of ketamine abusers presenting to the ED. Among the 20 patients in this series, common presenting complaints included anxiety, chest pain, and palpitations. Tachycardia was the most common physical examination finding. Nystagmus, a common finding after phencyclidine use, was seen in only three cases. The most frequent complications after ketamine abuse were severe agitation and rhabdomyolysis. The symptoms of ketamine intoxication appear to be short-lived, with 18 of the 20 patients discharged from the ED within 5 h of presentation. Emergency physicians should include ketamine in the differential diagnosis of drug- or toxin-induced hallucinations. Methods for detecting this drug in biologic fluids are reviewed as are treatment recommendations for managing the patient who presents to the ED after abusing ketamine.

Emerging drugs of abuse in Connecticut.

During the past decade, several new drugs of abuse have emerged as public health concerns in Connecticut. These include ketamine, gamma-hydroxybutyrate, methylphenidate (Ritalin), and "Illy." Two trends stand out when one looks at these new drugs of abuse. First, drugs that have legitimate medical indications are being increasingly diverted for illicit purposes. Second, much of the information needed to acquire, synthesize, and use these drugs can be found on the Internet. While none of these newer agents is abused to the extent of heroin or cocaine, all of them have the potential to cause serious morbidity, and occasionally death. The goal of this article is to make Connecticut physicians aware of these emerging drugs of abuse. Emphasis is placed on recognizing the signs and symptoms produced by these drugs and on managing the complications that are associated with their use.

Violence prevention program targeting Connecticut adolescents: description and preliminary results.

Recent statistics show that adolescents are increasingly becoming both the perpetrators and the victims of violent crime in our nation. At our institution, we have developed a violence prevention program specifically targeting adolescents. This three-hour workshop utilizes a multimedia style of presenting information that we believe is well suited to young audiences. To date, over 1,000 adolescents from all over the state have participated in our program. In addition to describing the program, we also summarize the results of program evaluations and demographic profiles completed by audience members. Most participants report that the program was successful in educating them about the causes and consequences of violent injury and offered them alternatives to violence in resolving difficult situations. It is our hope that the education we provide will translate into fewer violent injuries within the state of Connecticut.

Serotonin syndrome: case report and review of the literature.

We present the case of a 35-year-old woman who developed serotonin syndrome after receiving a single dose of the cyclic antidepressant imipramine (Tofranil). She was already being treated for depression with paroxetine (Paxil), a selective serotonin reuptake inhibitor. Two hours after receiving imipramine, the patient developed tachycardia, delirium, bizarre movements, and myoclonus, all classic findings of serotonin syndrome. Her antidepressants were discontinued and she was treated with intravenous fluids, sedation, and a short course of cyproheptadine, a serotonin receptor antagonist. All symptoms resolved completely within 24 hours. In this case report, we review the drug interactions that can precipitate serotonin syndrome, and give recommendations for the diagnosis and treatment of this potentially fatal disorder.

Liposomes for protein delivery: selecting manufacture and development processes.

The use of liposomes as protein carriers has been investigated for a number of possible potential applications in pharmaceutical formulations. These are for sustained release to improve adjuvancy for vaccine development, protein absorption enhancement, and drug targeting carriers and as vehicles for administration of hydrophobic compounds. The majority of current liposomal protein formulations are still in various preclinical research stages, with relatively little known or reported human clinical findings to date. There are still pending challenges to creating commercially stable and bioactive protein formulations with lipids. In addition to lipid developmental issues, because the stability of proteins may be affected by many physical or chemical manipulations, the choice of manufacturing designs for liposomal incorporation becomes somewhat more complex. For this reason, solvent-free vesicle procedures should be the primary approach to the preparation of protein-based formulations. In this regard a variety of recently reported methods are discussed. The advantages or disadvantages of these procedures are compared to those of procedures involving solvents. Consideration to large-scale manufacturing and protein recovery issues is also given.

Differential regulation of copper and zinc metabolism in rat liver parenchymal cells in primary cultures.

A variety of factors influence copper and zinc metabolism in primary cultures of rat hepatocytes. Pronounced elevations in accumulated 64Cu were produced by incubating cells with either Cu2+ or epinephrine with moderate increases produced by incubation with cycloheximide, actinomycin D, or dexamethasone. In addition, copper accumulation was enhanced when cells received culture medium more highly enriched in amino acids and other nutrients. Hepatocytes accumulate greater quantities of 65Zn when incubated with dexamethasone or high extracellular zinc. Higher levels of metallothionein were found in cells incubated with either dexamethasone, zinc, or copper but not with epinephrine. However, epinephrine was effective in elevating ceruloplasmin levels in the cell cytosol. Incubation with dexamethasone or copper-containing medium resulted in elevated 3H-ceruloplasmin in both cytosol and medium. Data presented suggest hormones influence copper and zinc metabolism in liver parenchymal cells in a differential fashion.

Hormonally produced changes in caeruloplasmin synthesis and secretion in primary cultured rat hepatocytes. Relationship to hepatic copper metabolism.

Hormonally produced changes in the synthesis and secretion of the serum copper-containing protein caeruloplasmin were studied in primary cultures of rat liver parenchymal cells isolated by the collagenase-perfusion technique. A rabbit antibody directed against rat caeruloplasmin was used to immunoprecipitate labelled caeruloplasmin. Isolated liver cells synthesized and secreted caeruloplasmin over a period of 3 days. Synthesis and secretion of this protein was enhanced when cells were treated with dexamethasone. The accumulation of copper was also moderately enhanced with glucocorticoid treatment. Inclusion of adrenaline in the culture medium resulted in elevated incorporation of copper into newly synthesized caeruloplasmin as well as an increase in 64Cu-labelled caeruloplasmin in the culture medium. However, adrenaline did not seem to increase the secretion of 3H-labelled protein, despite the elevation in secreted 64Cu-caeruloplasmin. This may be due to a large increase in the intracellular pool of 64Cu caused by enhanced accumulation of this metal when adrenaline is included in the incubation medium. Enhanced copper accumulation was also seen when cells were treated with glucagon. Adrenaline-stimulated accumulation of 64Cu could be inhibited by including phenoxybenzamine, an alpha-adrenergic blocker, in the culture medium. Elevation of extracellular copper caused enhancement in the detection of labelled caeruloplasmin in the medium of cultured cells, probably owing to the ability of this metal to stabilize the protein.

Anticholinergic poisoning with adulterated intranasal cocaine.

In recent years, emergency physicians have encountered a growing number of patients who present with anticholinergic toxicity after using adulterated heroin. Anticholinergic poisoning caused by adulterated cocaine is far less common. This report describes the case of a 39-year-old man who arrived in the emergency department several hours after the nasal insufflation of cocaine. Classic symptoms of anticholinergic toxicity were evident on examination, including dry, flushed skin, agitation, tachycardia, mydriasis, and absence of bowel sounds. Treatment included intravenous fluids and lorazepam, with resolution of symptoms over several hours. Urine samples revealed the presence of cocaine metabolites as well as the anticholinergic drug atropine, and infrequently encountered adulterant of cocaine. Anticholinergic poisoning is reviewed, and the physical examination findings that distinguish this syndrome from the closely related sympathomimetic syndrome typical of cocaine are detailed. Current treatment recommendations for anticholinergic poisoning are summarized.

Encapsulation of indomethacin in liposomes provides protection against both gastric and intestinal ulceration when orally administered to rats.

Encapsulation of indomethacin into egg phosphatidylcholine (EPC) monophasic vesicles (MPV) or into stable plurilamellar vesicles (SPLV) before oral administration to rats substantially reduced or eliminated the gastric and intestinal ulceration normally associated with ingestion of this drug. Ulcers were assessed by the 4-hour single-dose gastric ulceration model and the 4- or 14-day repeated-dose intestinal ulceration model, using microscopic/planimetric quantitation. Oral dosages of up to 10 mg/kg of indomethacin in polyethylene glycol-400 resulted in substantial gastric ulceration, but not when given in methylcellulose suspension or as EPCMPV. Severe intestinal ulcers resulted following oral administration of indomethacin in either vehicle at daily 3-4-mg/kg doses, but did not result from EPCMPV formulations, whether dosed for 4 days or 14 days. Oral administration of pH-sensitive indomethacin liposomes constructed from cholesterol hemisuccinate resulted in loss of the protective action. Indomethacin-MPV showed both comparable bioactivity and comparable blood levels of the drug when contrasted with free drug in vehicles. Biodistribution studies demonstrated that when delivered from liposomes, drug and phospholipid are rapidly cleared through the stomach but then are differentially absorbed. Empty EPCMPV given by mouth also offered some protection against ulcers induced by systemic (subcutaneous) introduction of indomethacin, although better protective action was noted when the drug was first liposome-encapsulated and then given orally. The application of liposomes to the development of nonsteroidal antiinflammatory drugs that have minimal gastrointestinal side effects is discussed.

Novel liposome composition for a rapid colorimetric test for systemic lupus erythematosus.

This test for systemic lupus erythematosus utilizes a novel liposome composition entrapping the cation-responsive red dye Arsenazo III. In dilutions of normal sera the liposome membranes undergo a rearrangement when divalent cations are added, resulting in the release of the encapsulated dye and the rapid formation of a stable blue cation-dye complex. Microliter amounts of sera from patients with active lupus stabilize the liposome preparation such that the vesicles remain intact in the presence of the added divalent cations and thus maintain their red color for extended periods. The assay requires 1-min incubations in sera at room temperature and can be performed with standard microtiter plates, allowing the screening of large numbers of serum samples in a short time. Moreover, the unique absorption spectra of the complexed and uncomplexed dye allow for quantification of results.

Inflammatory disease in HLA-B27 transgenic rats.

UNLABELLED: A spontaneous inflammatory disease in rats transgenic for HLA-B27 resembles the B27-associated human spondyloarthropathies. Colitis and arthritis, the two most important features, require T cells, gut bacteria, and high expression of B27 in bone marrow-derived cells. Control rats with HLA-B7 remain healthy. Most rats with HLA-Cw6 (associated with psoriasis vulgaris) remain healthy; a minority develop mild and transient disease. Rats with a mutant B27 with a Cys67-->Ser substitution resemble wild-type B27 transgenics, but with a lower prevalence of arthritis. A similar phenotype is seen in B27 rats co-expressing a viral peptide that binds B27. Disease-prone LEW but not F344 B27 rats develop high serum IgA levels concurrent with disease progression. Colitis is associated with high interferon-gamma, arthritis with high interleukin-6. Disease is similar in B27 LEW, F344, and PVG rats, but the DA background is protective. CONCLUSIONS: The spondyloarthropathy-like disease in rats is specific for HLA-B27 but does not require Cys67. Arthritis but not colitis is particularly sensitive to B27 peptide-binding specificity. Genetic background exerts a strong influence, but some phenotypic differences exist between permissive strains that do not influence disease susceptibility. The data favor a role for B27 peptide presentation in arthritis, but other mechanisms to explain the role of B27 have not been excluded.