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J Kloss

Publications and source records attributed to J Kloss.

15 recordsLinked to original sources
PubMed2001

Postmortem blood free and total morphine concentrations in medical examiner cases.

This purpose of this study was to determine the relationships between postmortem free morphine and total morphine levels in a large series of medical examiner morphine and heroin related deaths. Free morphine, total morphine, and 6-monoacetylmorphine (6-MAM) concentrations were measured by gas chromatography-mass spectrometry (GC-MS) in 87 medical examiner cases over 20 months. The mean total morphine concentration, mean free morphine concentration, and mean percent free morphine for all cases were: 2.3 mg/L (SD 5.2 mg/L), 0.5 mg/L (SD 1.6 mg/L), and 19.4% (SD 22.8%); respectively. Regression analyses showed weak correlations between total and free morphine concentrations over the entire concentration range (0 to 36.6 m/L, r = 0.603, n = 91) and over a subset concentration range of 0 to 1.0 mg/L (r = 0.369, n = 54). Twenty-three out of 56 (41%) tested positive for 6-MAM, indicative heroin abuse cases. Lower total and free morphine concentrations and a higher percent free morphine were found in individuals with detectable 6-MAM. Comparing blood concentrations for cases with and without detectable 6-MAM demonstrated mean total morphine concentrations of 0.9 mg/L versus 2.1 mg/L (p = 0.05), mean free morphine concentrations of 0.3 mg/L versus 0.4 mg/L (p = 0.21), and mean percent free morphine of 34.7% versus 13.7% (p < 0.003), respectively. Our findings demonstrate higher free to total morphine ratios in individuals with detectable 6-MAM than in individuals without 6-MAM. The database established in this study may assist medical examiners in the evaluation of postmortem blood opiates regarding the cause of death in opiate related ingestion cases.

Autopsy↗
PubMed2000

Evidence-based implementation of free phenytoin therapeutic drug monitoring.

BACKGROUND: The majority of laboratories measure total phenytoin concentration for therapeutic drug monitoring. However, there are substantial interindividual variations in free phenytoin concentrations, the pharmacologically active component. METHODS: We describe the process and data used to implement monitoring of free phenytoin only in an urban medical center. Over a 6-week period, total and free phenytoin concentrations were measured, clinical charts reviewed, and indications for alterations in the percentage of free phenytoin fraction were determined. RESULTS: Of the 189 phenytoin requests from 139 patients, 136 data points were analyzed. Free phenytoin concentrations were 6.8-35.3%, with 50% outside the expected range of 8-12%. Clinical indications likely responsible for variations were hypoalbuminemia, drug interactions, uremia, pregnancy, and age. Overall, 30% of patients demonstrated a discrepancy between therapeutic, subtherapeutic, or supratherapeutic concentrations between free and total phenytoin concentrations. The largest discordance (53%) occurred in the patient group with free phenytoin <8% or >12%. CONCLUSIONS: This study supports previous clinical findings that monitoring total phenytoin is not as reliable as free phenytoin as a clinical indicator for therapeutic and nontherapeutic concentrations. Thus, we recommend that therapeutic monitoring should use free phenytoin concentrations only.

Adolescent↗
PubMed1992

Expression cloning of neurotrophic factors using Xenopus oocytes.

We have explored the potential for cloning novel neurotrophic factor cDNAs via assay of neurotrophic activities following expression in Xenopus oocytes. In this report, we describe the successful application of the method to tract rat ciliary neurotrophic factor (CNTF) activity from mRNA purified from cultured cells and from mRNA synthesized by in vitro transcription of a cDNA library. Rat C6 glioma cells, which had been previously shown to have CNTF-like activity (Westermann et al., 1988), were used as source material. We tested protein extracts of C6 cells using an in vitro assay of primary neurons from the chick ciliary ganglion (CCG assay) and detected a CNTF-like activity. RNA isolated from C6 cells was shown to direct the synthesis of the activity following microinjection into Xenopus oocytes and one-step fractionation of Xenopus extract. C6 mRNA was size-fractionated, and fractions encoding CNTF-like activity were cloned into a lambda phage vector at a site distal to a T7 promoter. Synthetic RNA transcribed from total library DNA was injected into Xenopus oocytes, and a CNTF-like activity in the oocyte extract was detected by the CCG assay. Further fractionation of library clones narrowed the presence of the clone encoding the CNTF-like activity to a pool containing 20,000 members. The presence of a full-length CNTF cDNA clone in this pool and partial clones in other pools was confirmed by Polymerase Chain Reaction (PCR) using oligonucleotides from the rabbit CNTF cDNA (Lin et al., 1989) as primers.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Sequence and structural organization of the human gene encoding ciliary neurotrophic factor.

Ciliary neurotrophic factor (CNTF) is a potent polypeptide hormone whose actions appear to be restricted to the nervous system where it promotes survival, neurotransmitter synthesis and neurite outgrowth in certain neuronal populations. We have cloned the gene encoding human CNTF (hCNTF) and have characterized its structure and organization. The hCNTF gene appears to be a unique-copy gene with a simple genetic organization, since only a single intron interrupts the coding domain. The hCNTF gene is located on chromosome 11, as determined using human-hamster somatic cell hybrids. The CNTF protein is highly conserved in evolution. The amino acid (aa) sequences of rat and rabbit CNTF translated from cDNAs display approx. 85% homology with the deduced aa sequence encoding hCNTF.

Amino Acid Sequence↗
PubMed1991

Stereospecific microbial reduction of 4,5-dihydro-4-(4-methoxyphenyl)-6-(trifluoromethyl-1H-1)-benzazepin+ ++-2-o ne.

A key intermediate, (3R-cis)-1,3,4,5-tetrahydro-3-hydroxy-4-(4-methoxyphenyl)-6-(trifluorome thyl)- 2H-1-benzazepin-2-one (compound II or SQ32191), with high optical purity was made by the stereoselective microbial reduction of the parent ketone 1. Several strains of bacterial and yeast cultures were screened for the ability to catalyse the stereoselective reduction of 4,5-dihydro-4-(4-methoxyphenyl)-6-(trifluoromethyl)-1H-1-benzazepin++ +-2,3-dione [compound I or SQ32425]. Microorganisms from the genera Nocardia, Rhodococcus, Alkaligenes, Corynebacterium, Arthrobacter, Hansenula, and Candida reduced compound I to compound II with 60-70% conversion yield. In contrast, microorganisms from the genera Pseudomonas and Acinetobacter reduced compound I stereospecifically to (trans)-1,3,4,5-tetrahydro-3-hydroxy-4-(4-methoxyphenyl)-6-(trifluoromet hyl-2H- 1-benzazepin-2-one (compound III or SQ32408). Among various cultures evaluated, N. salmonicolor SC6310 effectively catalysed the transformation of compound I to compound II with 96% conversion yield at 1.5-2.0 gl-1 concentration. Compound II was isolated and identified by NMR analysis, mass spectrometry, and comparison to an authentic sample. Preparative scale fermentation process and transformation process were developed using cell suspensions of N. salmonicolor SC6310 to catalyse the transformation of compound I to compound II. The isolated compound II had a melting point of 222 degrees C (reference 221-223 degrees C), optical rotation of +130.4 (reference +128 degrees C), and optical purity of greater than 99.9% as analyzed by NMR and chiral HPLC.

Bacteria↗
PubMed1991

A team format for the Global Assessment Scale: reliability and validity on an inpatient unit.

The Global Assessment Scale (GAS) is a 100-point rating instrument which purports to measure psychological adjustment on a continuum from self-actualization to severe regression. Its reliability and validity were examined on the admitting ward of a state hospital where GAS ratings are assigned to patients by computing a mean of the individual ratings assigned by a team of clinicians. Results showed such team GAS ratings to have good reliability. As for validity, team GAS predicted the outcomes of court hearings at two stages of the civil commitment process and showed construct validity in its relevant correlations with the Psychotic Inpatient Profile. A predicted association between team GAS and a ward atmosphere measure was not obtained. Taken as a whole, the results support the use of team GAS ratings in inpatient settings.

Adaptation, Psychological↗
PubMed1989

Cloning and recombinant expression of phospholipase A2 present in rheumatoid arthritic synovial fluid.

Synovial fluid from arthritic patients contains multiple forms of phospholipase A2 (PLA2), as resolved by high performance liquid chromatography (Seilhamer, J.J., Plant, S., Pruzanski, W., Schilling, J., Stefanski, E., Vadas, P., and Johnson, L. K. (1989) J. Biochem. (Tokyo), submitted for publication). Here we describe the cloning of a human 4.5-kilobase gene and 800-base pair cDNA encoding the form representing the major peak of activity and protein mass (peak A). The clones encode a mature peptide of 124 amino acids, which follows a prepeptide of 20 residues. The deduced amino acid sequence constitutes an enzyme of the "Type II" class of PLA2s, and resembles PLA2s from other mammalian sources. This represents the first report of a full length mammalian non-pancreatic PLA2 sequence. Active transcription of this PLA2 gene was detected in two different inflammatory cell sources. Recombinant human peak A PLA2 was expressed in vaccinia as a secreted protein which accumulated in conditioned medium.

Amino Acid Sequence↗
PubMed1987

CT for determining the results of treatment of fractures of the wrist.

Eighteen CT examinations of the wrist were performed in 13 patients to evaluate the results of treatment for carpal fractures. In four cases with metal objects and in seven with cast materials, there was no difficulty achieving adequate CT studies. In 13 cases CT was found to be helpful in determining bony union in the presence of advanced osteoporosis. In six cases CT was excellent in evaluating bone-graft incorporation. CT affords improved detection of fractures perpendicular to the plane of the scan and also shows small areas of bone disruption, even with osteoporosis. Axial CT images can evaluate Lister's tubercle, a bony prominence on the dorsum of the distal radius, for hypertrophy, which can occur secondary to traumatic and degenerative changes. A hypertrophied tubercle can impinge on the extensor pollicis longus tendon and cause atrophy and disruption. The high cost of CT is offset by the possibility of reducing the patient's period of immobilization and, thereby, the length of time the patient is unable to participate in normal activities. In addition, since CT is often definitive, the number of supplemental or follow-up radiologic procedures or clinical appointments should be reduced. We conclude that CT is useful in evaluating the results of treatment of wrist injuries.

Carpal Bones↗
PubMedDate not supplied

Cocaine, cocaine metabolite, and ethanol concentrations in postmortem blood and vitreous humor.

The use of postmortem cocaine and metabolite concentrations is a complex subject. This study was undertaken to determine (1) the usefulness of vitreous humor as a specimen, compared with blood, to quantitate cocaine and cocaine metabolites; (2) whether there is a preferential site of disposition for cocaethylene between vitreous humor and blood; and (3) if the presence of cocaethylene influences the concentration of benzoylecgonine in postmortem specimens. Cocaine, benzoylecgonine, and cocaethylene were quantitated in blood and vitreous humor by gas chromatography-mass spectrometry, and ethanol was quantitated by gas chromatography in 62 medical examiner cases. No differences were found between mean concentrations of vitreous cocaine 0.613 mg/L (standard deviation [SD] 0.994 mg/L), cocaethylene 0.027 mg/L (SD 0.59 mg/L), and ethanol 0.092 g/dL (SD 0.13 g/dL) compared to blood cocaine 0.489 mg/L (SD 1.204 mg/L), cocaethylene 0.022 mg/L (SD 0.055 mg/L), and ethanol 0.058 g/dL (SD 0.91 g/dL), respectively. However, a statistical difference was found between mean benzoylecgonine concentrations in vitreous 0.989 mg/L (SD 1.597 mg/L) and blood 1.941 mg/L (SD 2.912 mg/L) (p = 0.0004). Regression analysis demonstrated that linear relationships were present between concentrations of vitreous and blood cocaine (r = 0.854) and benzoylecgonine (r = 0.763). However, the correlation coefficients were lower for cocaethylene (r = 0.433) and ethanol (r = 0.343). There were variations between the concentrations of cocaine and metabolites both in terms of magnitude and also direction of change. Mean concentrations of benzoylecgonine in blood and vitreous were higher in cases where ethanol was absent, 2.593 mg/L (SD 3.195 mg/L) and 1.431 mg/L (SD 2.021 mg/L), compared to when ethanol was present, 1.199 mg/L (SD 2.396 mg/L) and 0.469 mg/L (SD 0.553 mg/L). This study demonstrates that vitreous humor may be used to quantitate cocaine and cocaine metabolites; however, because the concentrations of cocaethylene in vitreous humor and blood were not well correlated, vitreous humor may not be a reliable specimen for measuring cocaine and cocaine metabolite concentrations.

Autopsy↗
PubMedDate not supplied

The use of methylmethacrylate as a temporary spacer following en bloc resection of the distal femur.

The current state of the art of prosthetic joint replacement permits sizeable segments of the appendicular skeleton to be resected and replaced with prosthetic components which are secured with methylmethacrylate cement. Occasionally it is necessary to resect a rather sizeable area of pathologic bone and to provide for some type of temporary fixation until a specially fabricated prosthetic component can be made available. Under such circumstances it is necessary to maintain length of the involved extremity, and provide for skeletal stability to the area of resection. Although external fixation offers a reasonable option, the employment of an internal type of fixation in the form of titanium mesh reinforced with methylmethacrylate cement seems more desirable. With this technique, the potential problem of pin track infection is avoided while space suitable to the dimensions of the prosthetic implant can be preserved.

Adult↗