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T L Jones

Publications and source records attributed to T L Jones.

At least 55 records · Page 3Linked to original sources
PubMed1996

Gag rules.

When two parties enter into a business contract, they usually share an unspoken "gentlemen's agreement" that neither one will start bad-mouthing the other. But in the often shaky relationships between managed care plans and physicians, what was once assumed has increasingly become codified. Just a few years ago, little one- or two-sentence clauses began popping up in physicians' contracts with managed care plans around the country, which managed care plans call confidentiality clauses. The house of medicine calls them gag rules and says they are just another strong-armed tactic to stifle physicians' abilities to act as patient advocates.

Confidentiality↗
PubMed1996

TB roars back.

Explore the source record for details and available documents.

Disease Outbreaks↗
PubMed1995

Expression of an amphibian homolog of the Eph family of receptor tyrosine kinases is developmentally regulated.

In order to study the function of tyrosine kinase receptors during Xenopus development, we have isolated Xek (Xenopus Elk-like kinase), a tyrosine kinase receptor, which shows significant homology to rat Elk and chicken cek5, members of the Eph family. Xek exists as a maternally expressed mRNA which decreases in expression at the mid blastula transition and reappears at late neurulation in Xenopus. Xek mRNA is expressed at higher levels in the anterior and dorsal regions of embryonic stages 16, 24 and 37. In adult Xenopus tissues, Xek appears to be ubiquitously expressed with higher expression observed in brain and ovary. In situ hybridization analysis demonstrates localized mRNA expression in the brain, brachial arches, trigeminal facial ganglion, and the retina of the swimming tadpole stage of development. The similarities in sequence and expression pattern suggest that Xek is an amphibian member of the Eph family and may play a role in the development or function of the central nervous system.

Amino Acid Sequence↗
PubMed1995

Stimulation of Xenopus oocyte maturation by inhibition of the G-protein alpha S subunit, a component of the plasma membrane and yolk platelet membranes.

Oocytes of Xenopus laevis undergo maturation when injected with an affinity-purified antibody against the COOH-terminal decapeptide of the alpha subunit of the G-protein Gs, an antibody that inhibits Gs activity. Germinal vesicle breakdown, chromosome condensation, and polar body formation occur, with a time course similar to that for oocytes treated with progesterone. The alpha S antibody-injected oocytes also acquire the ability to be activated by sperm. Coinjection of the catalytic subunit of cAMP-dependent protein kinase, or incubation with cycloheximide, inhibits maturation in response to injection of the alpha S antibody; these experiments show that the alpha S antibody acts at an early point in the pathway leading to oocyte maturation, before formation of maturation promoting factor, and like progesterone, its action requires protein synthesis. Immunogold electron microscopy shows that alpha S is present in the yolk platelet membranes as well as the plasma membrane. These results support the hypothesis that progesterone acts by inhibiting alpha S, and suggest that the target of progesterone could include yolk platelet membranes as well as the plasma membrane.

Amino Acid Sequence↗
PubMed1995

Lactobacillemia in three patients with AIDS.

Lactobacillemia, an uncommon cause of bacteremia, has been reported to occur in one renal transplantation patient who was also infected with human immunodeficiency virus (HIV). We present the cases of three patients with AIDS in whom lactobacillemia developed. All three patients had late-stage AIDS with CD4 cell counts of < 55/mm3, all had indwelling central venous catheters, and all were recently or concomitantly blood culture-positive for coagulase-negative staphylococci. In addition, two of the three patients had recently received vancomycin therapy. These three cases provide the first association of lactobacillus bacteremia and AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Legislative soup, rule-making salad. Lawmakers and state agencies serve up 5.01(a) rules.

One response to tremendous changes in the health-care industry has been the formation of more and more physician/hospital organizations (PHOs). One kind of PHO has grown rapidly in Texas. Commonly referred to simply as the 5.01(a)--its section number in the Medical Practice Act of Texas that describes how it is formed and what it can do--the number of these nonprofit health-care corporations has more than quadrupled in Texas in the past 5 years, increasing from 36 in 1990 to 160 in 1995.

Hospital-Physician Joint Ventures↗
PubMed1995

Religion's role in health. What's God got to do with it?

Sex, politics, and religion were once polite-conversation no-no's. But as Victorian sensibilities gave way to modern ones, society has loosened up, leaving few value-laden topics taboo. Government's regulatory grip on health care has made any comprehensive discussion of medicine incomplete without some mention of politics. Epidemic rates of AIDS and sexually transmitted diseases have forced medicine's participation in debates about sexuality. But religion has remained pretty much a nontopic, scientifically speaking, until relatively recently.

Humans↗
PubMed1995

Slam-dunked. New law forces insurance carriers to reduce rates.

No one saw it coming. Not consumer groups, not business or special interest groups, and especially not insurance carriers. The Texas Legislature did something this session no legislature had ever done, experts say. It ordered insurance carriers to cut premiums in practically all insurance lines, and for physicians, this will mean a 10% reduction in medical professional liability premiums effective January 1, 1996. Hospitals will see a 13% cut.

Insurance Carriers↗
PubMed1994

Palmitoylation of a G protein alpha i subunit requires membrane localization not myristoylation.

Palmitoylation is a dynamic, post-translational modification of the amino terminus of heterotrimeric G protein alpha subunits. Since myristoylation, beta gamma interactions, and membrane attachment also involve the amino terminus of the G protein alpha i1 subunit, we studied the relationships between palmitoylation and these events. Using COS cell transfection, the turnover of palmitate was slower on alpha i1 subunits co-expressed with beta and gamma subunits than on the alpha i1 subunit expressed alone. Mutation of cysteine 3 of alpha i1 prevented [2H]palmitate but not [3H]myristate incorporation and decreased the membrane localization of this protein. This nonpalmitoylated mutant could form a heterotrimer with co-expressed beta gamma subunits which restored its membrane localization. A nonmyristoylated alpha i1 mutant (glycine 2 to alanine) could incorporate [3H]palmitate when co-expressed with beta gamma subunits and localized to the membrane. The [3H]palmitate turnover of this nonmyristoylated mutant was more rapid than seen with the wild-type alpha i1 subunit. While myristoylation is not required for palmitoylation, both myristoylation and beta gamma association can slow the turnover of palmitate on alpha i1. These results suggest that palmitoylation maintains the membrane attachment of the free alpha subunit and changes in beta gamma association could modulate palmitoylation during signaling.

Amino Acid Sequence↗
PubMed1994

Alteration of cell cycle kinetics and immunoglobulin gene transcription as the result of multiple agonist stimulation of murine B cells.

Several laboratories have established that anti-IgM can inhibit polyclonal B cell activation by LPS or LPS/DxS. The use of intact anti-IgM results in an inhibition of both proliferation and differentiation, whereas F(ab')2 fragments inhibit only differentiation. Since signal transduction by both alpha-Ig's (intact and F(ab')2 fragments) is known to be mediated by PIP2 hydrolysis, we have investigated the effects of A23187 and PMA on LPS/DxS activation of splenic B cells. These agents mimic the second messengers generated as the results of PIP2 hydrolysis. As with intact alpha-IgM, either agent in conjunction with LPS/DxS resulted in an inhibition of proliferation as assessed by [3H]thymidine uptake. However, when proliferation was assessed by acridine orange (AO) staining and flow cytometric analysis, cells were observed to have entered cell cycle. This disparity between AO staining and proliferation was resolved by using BrDu/Hoechst quenching analysis and revealed a delay in cell cycle transit time as the result of multiple agent stimulation. Since both anti-IgM's result in the inhibition of differentiation, we also investigated the effects of these agents on differentiation normally observed with LPS/DxS alone activation of B cells. A23187 and PMA, either alone or in combination, were observed to result in a decrease in mRNA-encoding mu immunoglobulin of the 2.4-kb mRNA for secreted IgM.

Animals↗
PubMed1994

The membrane localization of the G protein alpha s subunit is not dependent on its TENIR sequence or effector domain.

The GS protein alpha subunit (alpha S) sequences conserved in non-myristoylated alpha subunits (TENIR, residues 369-373) or critical for adenylyl cyclase interaction were investigated as possible sites required for membrane localization. Substitutions were created by site-directed mutagenesis in which the TENIR residues were deleted from alpha S or added to the soluble, non-myristoylated alpha i1. After transfection, COS cells were separated by centrifugation into particulate and soluble fractions. Immunoblots showed that these substitutions did not change the localization: alpha S +/- TENIR in the particulate fraction, non-myristoylated alpha i1 +/- TENIR in the soluble fraction. The constitutively active alpha i/alpha S chimera (CH4A), containing four regions of alpha S sufficient for adenylyl cyclase activation, was mutated to prevent myristoylation (GA-CH4A). Immunoblots of transfected COS cell fractions showed CH4A in the particulate and GA-CH4A in the soluble fraction. While these regions did not lead to membrane localization, the soluble GA-CH4A could activate adenylyl cyclase in the intact cell and after reconstitution with cyc- membranes.

Adenylyl Cyclases↗
PubMed1994

From diabetic ketoacidosis to hyperglycemic hyperosmolar nonketotic syndrome: the spectrum of uncontrolled hyperglycemia in diabetes mellitus.

Diabetic ketoacidosis and hyperglycemic hyperosmolar nonketotic syndrome are two examples of uncontrolled hyperglycemia in diabetes mellitus that may prove life threatening. Both disorders result from a breakdown in glucose homeostasis caused by a relative or absolute insulin deficiency. This article compares and contrasts these two disorders with regard to pathogenesis, clinical presentation, and management.

Diabetic Ketoacidosis↗