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S Cline

Publications and source records attributed to S Cline.

11 recordsLinked to original sources
PubMed1994

Three distinct human thymopoietins are derived from alternatively spliced mRNAs.

Thymopoietin (TP) was originally isolated as a 5-kDa 49-aa protein from bovine thymus in studies of the effects of thymic extracts on neuromuscular transmission and was subsequently observed to affect T-cell differentiation and function. We now report the isolation of cDNA clones for three alternatively spliced mRNAs that encode three distinct human T-cell TPs. Proteins encoded by these mRNAs, which we have named TP alpha (75 kDa), TP beta (51 kDa), and TP gamma (39 kDa), contain identical N-terminal regions, including sequences nearly identical to that of the originally isolated 49-aa protein, but divergent C-terminal regions. TP mRNAs are expressed in many tissues, most abundantly in adult thymus and fetal liver of the tissues so far examined. Distinct structural domains and functional motifs in TPs alpha, beta, and gamma suggest that the proteins have unique functions and may be directed to distinct subcellular compartments.

Alternative Splicing↗
PubMed1994

Treatment of high-dose intrathecal morphine overdose. Case report.

The case is reported of a 45-year-old woman who was being treated for chronic back and right leg pain with intrathecal morphine administered via a subcutaneous continuous-infusion device. She received an accidental 450-mg bolus injection of morphine intrathecally and developed hypertension, status epilepticus, intracerebral hemorrhage, and respiratory failure. Treatment with continuous intravenous naloxone infusion, lumbar catheter drainage of cerebrospinal fluid, and control of hypertension and status epilepticus resulted in an excellent outcome with return to neurological baseline. Care providers who refill pump reservoirs with morphine must be knowledgeable about these devices and the life-threatening consequences associated with errors in refilling them. This case describes the complications and successful treatment of high-dose intrathecal morphine overdose.

Drug Overdose↗
PubMed1986

The translational efficiency of tRNA is a property of the anticodon arm.

We have reciprocally transplanted the anticodon arm sequences of a set of amber suppressor tRNA genes, using recombinant DNA techniques. By this means, a very efficient suppressor may be converted to a poor one, and the poorest tRNA to the efficiency of the best one. In tRNA molecules of normal 2 degrees and 3 degrees structure, the suppressor efficiencies of different composite tRNAs having the same anticodon arm sequence are approximately the same. Large numbers of simultaneous changes throughout the rest of the molecule do not affect the efficiency. Selective nucleotide modification as a result of varied anticodon arm sequences cannot explain these efficiencies. Efficiencies are also unlikely to differ because of selective aminoacylation. Measurement of in vivo tRNA shows, however, that tRNA levels do vary if the anticodon arm sequence is changed. If tRNA levels are normalized, the anticodon arm effect on the translational efficiency remains. Therefore, different anticodon arms, all of normal secondary structure, are not equivalent in translation. The most efficient sequences in this series resemble those found in natural tRNAs associated with similar anticodons, as is proposed in the extended anticodon theory (Yarus, M. (1982) Science 218, 646-652). These molecules also provide some information on the specificity of nucleotide modification enzymes and on determinants of the steady-state tRNA level.

Anticodon↗
PubMed1983

Follow-up of hydration and sedation in the pretherapy of premature labor.

Intravenous fluids and sedation with 8 mg of morphine sulfate intramuscularly has been used for the last 12 years at our institution to define the patients in "real" premature labor. Only those who continue to have uterine contractions after this pretreatment are considered in actual premature labor. One hundred eighty-four pregnant patients with singleton pregnancies were evaluated after they were treated with hydration and sedation for the presence of regular uterine contractions. Fifty-five percent of the patients responded to hydration and sedation, and the rest required the use of tocolytic therapy. In the tocolytic therapy group, 11% gave birth to infants who were small for gestational age. The patients who responded to hydration and sedation had a 2.6-fold increase of delivering prematurely when compared to the general population. However, more than 85% of the patients who received only hydration and sedation were delivered more than 2 weeks after the first episode and most of them were delivered at term. Therefore, the use of hydration and sedation seems a useful and safe clinical test to determine patients in real premature labor. Patients who respond to hydration and therapy constitute a "high-risk group" and should be managed accordingly.

Adrenergic beta-Agonists↗
PubMed1981

Factors affecting diazepam infusion: solubility, administration-set composition, and flow rate.

The sorption of diazepam in large-volume i.v. admixtures to administration-set components and in i.v. containers was analyzed quantitatively. Solubility of diazepam in phosphate buffer at various pH levels and in i.v. fluids was measured. Partition coefficients of diazepam into components of i.v. administration sets and i.v. containers were studied by shaking a solution of diazepam in 0.9% sodium chloride, with finely cut components and measuring the change in diazepam in the aqueous phase. Flow studies through an administration set of a 0.04-mg/ml diazepam solution in 5% dextrose injection were done, varying both the flow rate and the length of tubing. The maximum free-base solubility of diazepam in phosphate buffer was 0.048 mg/ml; its solubility was 0.058, 0.050, and 0.064 mg/ml in lactated Ringer's, 0.9% sodium chloride, and 5% dextrose injections, respectively. Equilibrium partition coefficients were highest for polyvinyl chloride tubing and flexible bags. Volume-control sets made of cellulose propionate had lower but sufficiently large partition coefficients to cause diazepam loss. Polyolefin semi-rigid and glass containers had low partition coefficients. In the flow studies, the amount of solution-contact time correlated with the extent of absorption. As flow rate decreased or tubing length increased, the amount of diazepam absorbed increased proportionately. A nomogram and a predictive dosing chart are presented for calculation of actual diazepam doses delivered at various flow rates and tubing lengths. Diazepam can be administered safely and effectively by i.v. infusion. The use of volume-control sets and flexible polyvinyl chloride bags should be avoided with diazepam solutions. Polyolefin semi-rigid containers are acceptable alternatives to glass. The concentration of diazepam infusions should not exceed 0.04 mg/ml.

Absorption↗
PubMed1980

Construction of a composite tRNA gene by anticodon loop transplant.

By using sites for the restriction nuclease Hpa II, the information for the anticodon stem and loop of an altered Su+2 amber suppressor tRNA (a mutant of tRNAGln) has been transplanted to a specially prepared tRNATrp gene, which lacks it homologous anticodon stem and loop sequence. The resulting tRNA gene was cloned under lac operator-promoter control. The result is a functional, hybrid, amber-suppressor tRNA that can exhibit a moderately high efficiency in translation. It appears less efficient, however, than Su+7 tRNA, the amber suppressor that results from a direct anticodon mutation in tRNATrp. As judged by its suppressor spectrum, which is almost identical to the spectra of Su+2, and Su+7, the recomposed tRNA inserts glutamine at amber sites. This experiment is the prototype of a series of construction that examine the role of the nucleotides in the anticodon region.

Anticodon↗