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Showing papers by "Baylor College of Medicine published in 1983"



Journal ArticleDOI
TL;DR: Identification of particular persons who will commit suicide is not currently feasible, because of the low sensitivity and specificity of available identification procedures and the low base rate of this behavior.
Abstract: A prospective research study attempted to identify persons who would subsequently commit or attempt suicide. The sample consisted of 4,800 patients who were consecutively admitted to the inpatient psychiatric service of a Veterans Administration hospital. They were examined and rated on a wide range of instruments and measures, including most of those previously reported as predictive of suicide. Many items were found to have positive and substantial correlations with subsequent suicides and/or suicide attempts. However, all attempts to identify specific subjects were unsuccessful, including use of individual items, factor scores, and a series of discriminant functions. Each trial missed many cases and identified far too many false positive cases to be workable. Identification of particular persons who will commit suicide is not currently feasible, because of the low sensitivity and specificity of available identification procedures and the low base rate of this behavior.

672 citations


Journal ArticleDOI
TL;DR: The identification of cAMP-dependent protein kinase, calmodulin and myosin light chain kinase in the sperm head suggests that cAMP and calcium-dependent phosphorylations are also involved in the control of the fertilization process, i.e., the acrosome reaction, in a manner similar to that known for theControl of stimulus/secretion coupling.
Abstract: cAMP and calcium are two important regulators of sperm flagellar motility. cAMP stimulates sperm motility by activating cAMP-dependent protein kinase and catalyzing the phosphorylation of sperm proteins. The stimulation of sperm motility by cAMP appears to be at two different levels. Evidence has been presented to suggest that cAMP-dependent phosphorylations may be required in order for motility to be initiated. In addition, cAMP-dependent phosphorylation appears to modulate specific parameters of motility resulting in higher beat frequency or greater wave amplitude. Calcium, on the other hand, when elevated intracellularly to 10(-6) M or higher, inhibits flagellar motility. The calcium-binding protein, calmodulin, appears to mediate a large number of effects of calcium on motility. Evidence suggests that calcium-calmodulin may be involved at the level of the membrane to pump calcium out of the flagellum. In addition, calcium-calmodulin may be involved in the control of axonemal function by regulating dynein ATPase and myosin light chain kinase activities. The identification of cAMP-dependent protein kinase, calmodulin and myosin light chain kinase in the sperm head suggests that cAMP and calcium-dependent phosphorylations are also involved in the control of the fertilization process, i.e., the acrosome reaction, in a manner similar to that known for the control of stimulus/secretion coupling. Finally, the effects of cAMP on flagellar motility are mediated by protein phosphorylation while the effects of calcium on motility are also in part, mediated by effects on protein phosphorylation.

385 citations


Journal ArticleDOI
06 May 1983-Science
TL;DR: The abilities of B16 melanoma cells to extravasate and successfully colonize the lung may be related to their capacities to degrade heparan sulfate in the walls of pulmonary blood vessels.
Abstract: After transport in the blood and implantation in the microcirculation, metastatic tumor cells must invade the vascular endothelium and underlying basal lamina. Mouse B16 melanoma sublines were used to determine the relation between metastatic properties and the ability of the sublines to degrade enzymatically the sulfated glycosaminoglycans present in the extracellular matrix of cultured vascular endothelial cells. Highly invasive and metastatic B16 sublines degraded matrix glycosaminoglycans faster than did sublines of lower metastatic potential. The main products of this matrix degradation were heparan sulfate fragments. Intact B16 cells (or their cell-free homogenates) with a high potential for lung colonization degraded purified heparan sulfate from bovine lung at higher rates than did B16 cells with a poor potential for lung colonization. Analysis of the degradation fragments indicated that B16 cells have a heparan sulfate endoglycosidase. Thus the abilities of B16 melanoma cells to extravasate and successfully colonize the lung may be related to their capacities to degrade heparan sulfate in the walls of pulmonary blood vessels.

360 citations


Journal ArticleDOI
01 Dec 1983-Nature
TL;DR: The results suggest that the nuclear matrix is the site of nuclear transcription and may represent another potential level of control for regulation of gene expression in the eukaryotic cell.
Abstract: In the chicken oviduct, it has been well documented that steroid hormones stimulate the transcription of specific genes such as the ovalbumin gene. In addition to the presence of specific hormone receptors in the tissue, gene expression seems to require that target genes exist in large DNase I sensitive chromosomal domains. This structure appears necessary but not sufficient for transcriptional activation. In search of still other levels of control, we have investigated the interactions of genes with the nuclear matrix, a structure which has been implicated in DNA synthesis, transcription and RNA processing. Here we have isolated nuclear matrix and used a nondegradative method to fractionate nuclear DNA based on its preferential association with the matrix. The preparation was digested with a restriction enzyme and both matrix-bound and released DNAs were recovered. We found that only actively expressed genes were associated with the matrix. Furthermore, within a 100-kilobase (kb) DNase I sensitive chromosomal domain, only the transcribed regions were associated with the matrix. This association was shown to be reversible when hormone was withdrawn. Our results suggest that the nuclear matrix is the site of nuclear transcription and may represent another potential level of control for regulation of gene expression in the eukaryotic cell.

358 citations


Journal ArticleDOI
TL;DR: Immunofluorescence tests showed that more than 25% of the cell cultures from both types of sample contained antigens of human cytomegalovirus (CMV) but not of herpes simplex virus type 1 or type 2, suggesting that the artery walls may be a site of CMV latency.

320 citations


Journal ArticleDOI
10 Nov 1983-Nature
TL;DR: Fe feasibility studies of prenatal diagnosis of classical phenylketonuria and identification of carriers of the trait indicate that these services could be provided for up to 75% of all families with phenyl ketonuric children in the general Caucasian population.
Abstract: The human gene for the hepatic enzyme phenylalanine hydroxylase has been cloned and used to analyse the phenylalanine hydroxylase locus in the human genome. The detection of polymorphisms in this locus by several restriction enzymes has allowed feasibility studies of prenatal diagnosis of classical phenylketonuria and identification of carriers of the trait. Results indicate that these services could be provided for up to 75% of all families with phenylketonuric children in the general Caucasian population.

302 citations


Journal ArticleDOI
21 Apr 1983-Nature
TL;DR: It is shown here that Cyc− S49 cells contain a substrate for ADP-ribosylation by pertussis toxin and that the toxin alters GTP dependent inhibition of cyc− adenyl cyclase activity, and it is concluded that Ni is a distinct and separate regulatory component of adenylyl cyclase.
Abstract: Adenylyl cyclases are under positive and negative control by guanine nucleotides and hormones1–3. Stimulatory responses are mediated by a guanine nucleotide- and Mg-binding regulatory component4–6 (Ns), a protein that has been purified to homogeneity7–9. Inhibitory responses have been hypothesized1–3,10,11 to be mediated by an analogous regulatory component (Ni) distinct from Ns, but definitive proof for this is lacking and these effects may result from modulation of Ns activity. Recently, Bordetella pertussis toxin has been shown12 to ADP-ribosylate a peptide that is not part of Ns, and this coincides with attenuation of hormonal inhibition of adenylyl cyclase12–17. We show here that cyc− S49 cells contain a substrate for ADP-ribosylation by pertussis toxin and that the toxin alters GTP dependent inhibition of cyc− adenyl cyclase activity18. As cyc− S49 cells do not contain Ns by several criteria5,19–24, we conclude that Ni is a distinct and separate regulatory component of adenylyl cyclase.

302 citations


Journal ArticleDOI
TL;DR: Tetrabenazine, lithium, and trihexyphenidyl were most useful for the treatment of oromandibular dystonia, and clonazepam was useful in some patients with blepharospasm.
Abstract: We evaluated prospectively 100 patients, the largest reported series, with blepharospasm and orofacial-cervical dystonia, or Meige syndrome. The mean age at onset was 51.7 years, and 81% presented between the ages of 40 and 70. Women outnumbered men three to two. Blepharospasm was the initial symptom in 58 patients, but only 23 had involuntary movements localized to the orbicularis oculi. Sixty-one patients had the complete syndrome, blepharospasm and oromandibular dystonia, and 60 had neck or generalized dystonia in addition to the orofacial movements. Twenty-one patients with spasmodic dysphonia were included; in 12 of these patients, spasmodic dysphonia was part of the complete (Meige) syndrome, and 16 of these patients had neck or generalized dystonia or essential tremor. An organic cause of Meige syndrome is supported by a high correlation with essential tremor and other movement disorders and by positive family history in some patients. Response to medication was inconsistent, but 69% of patient trials resulted in some improvement; in 22% the benefit was marked and persistent. Tetrabenazine, lithium, and trihexyphenidyl were most useful for the treatment of oromandibular dystonia, and clonazepam was useful in some patients with blepharospasm.

286 citations


Journal ArticleDOI
01 Sep 1983-Cell
TL;DR: An immunochemical approach is utilized to define the structural location of these two myosins within body wall muscle thick filaments of the nematode, Caenorhabditis elegans, by immunofluorescence microscopy.

281 citations


Journal ArticleDOI
TL;DR: The adhesive properties in part determine the localization and retention of bacteria in the mouse urinary tract and the addition of adhesins to a commensal E. coli strain was not sufficient to confer colonization capacity comparable to that of a pyelonephritis strain.
Abstract: The affinity of uropathogenic Escherichia coli to kidneys and bladders of experimentally infected mice was shown to be determined in part by the adhesive properties of the infecting bacteria. Mice were infected with various pairwise combinations of two homogeneic sets of bacteria: (i) mutants derived from a human pyelonephritis E. coli isolate which were selected to express either or both adhesins specific for globoseries glycolipid receptors or for “mannosides”; and (ii) transformants of a normal fecal isolate which harbored recombinant plasmids encoding the genes for one or the other adhesin or which harbored only the vector plasmid. The relative efficiency of survival of the strains to be compared was evaluated in each animal by plating on selective media of samples of homogenized kidneys and bladders taken 24 h after intravesical inoculation. The presence of adhesins specific for globoseries glycolipid receptors, which mediate the in vitro mannose-resistant attachment to human and mouse uroepithelial cells, enhanced bacterial recovery from both kidneys and bladders of infected animals. The addition to the infecting strain of adhesins binding mannoside residues further improved bacterial recovery from the bladder, but not from the kidney. The mutants and transformants with adhesins binding only mannosides were recovered in higher numbers from the bladder than those expressing adhesins specific for the globoseries glycolipids only. There was apparent selection in vivo decreasing expression of mannoside binding adhesins in the kidneys, but not in the bladders, of animals infected with the mutant expressing both types of adhesins. Regardless of adhesive properties, the mutants of the pyelonephritis isolate were recovered in significantly higher numbers than the fecal isolate with adhesins encoded on recombinant plasmids. We conclude that the adhesive properties in part determine the localization and retention of bacteria in the mouse urinary tract. However, the addition of adhesins to a commensal E. coli strain was not sufficient to confer colonization capacity comparable to that of a pyelonephritis strain.

Journal ArticleDOI
TL;DR: The finding that there are high levels of glutamic acid decarboxylase in the cell bodies, dendritic shafts anddendritic appendages of intrinsic interneurons in the dorsal lateral geniculate nucleus of the rat, and in the axon terminals of fibres projecting to this site from the thalamic reticular nucleus, allows us to conclude that the inhibitory inputs to the geniculo-cortical projection cells from both of these sources are probably

Book ChapterDOI
TL;DR: The Rotavirus genus of the Reoviridae consists of a number of antigenically related and morphologically identical viruses that cause enteritis, primarily in young mammals and avians.
Abstract: The Rotavirus genus of the Reoviridae consists of a number of antigenically related and morphologically identical viruses that cause enteritis, primarily in young mammals and avians. The genus was established by the International Committee on Taxonomy of Viruses at the Fourth International Congress for Virology in 1978 (Matthews 1979). Type species, such as human and bovine rotavirus, have been proposed, but because there are multiple serotypes and cross-infection of heterologous species may occur these names may be difficult to formalize. It is clear that an acceptable nomenclature for rotavirus species is needed.

Journal ArticleDOI
01 Jul 1983-Nature
TL;DR: Chemically synthesized specific oligonucleotide probes (19-mer) have been used to develop a sensitive and direct test for the presence or absence of the mutant gene in any individual, which can be used for prenatal diagnosis of the deficiency syndrome.
Abstract: A deficiency in the plasma protease inhibitor α1-antitrypsin can cause chronic obstructive emphysema or infantile liver cirrhosis. This deficiency results from a single amino acid substitution created by a G to A transition in the gene for α1-antitrypsin. Chemically synthesized specific oligonucleotide probes (19-mer) have been used to develop a sensitive and direct test for the presence or absence of the mutant gene in any individual, which can be used for prenatal diagnosis of the deficiency syndrome.


Journal ArticleDOI
TL;DR: The biotin/avidin system was incorporated into the enzyme-linked immunosorbent assay (ELISA) technique to increase the sensitivity of the standard ELISA for the detection of mouse antibody to hepatitis B surface antigen.

Journal ArticleDOI
07 Jan 1983-JAMA
TL;DR: In this selected sample, short-term improvements in cardiovascular status seem to result from these adjuncts to conventional treatments of IHD.
Abstract: To evaluate the short-term effects of an intervention that consists of stress management training and dietary changes in patients with ischemic heart disease (IHD), we compared the cardiovascular status of 23 patients who received this intervention with a randomized control group of 23 patients who did not. After 24 days, patients in the experimental group demonstrated a 44% mean increase in duration of exercise, a 55% mean increase in total work performed, somewhat improved left ventricular regional wall motion during peak exercise, and a net change in the left ventricular ejection fraction from rest to maximum exercise of +6.4%. Also, we measured a 20.5% mean decrease in plasma cholesterol levels and a 91.0% mean reduction in frequency of anginal episodes. In this selected sample, short-term improvements in cardiovascular status seem to result from these adjuncts to conventional treatments of IHD. ( JAMA 1983;249:54-59)

Journal ArticleDOI
TL;DR: Silver staining during mitosis closely paralleled the distribution of protein C23, supporting previous conclusions thatprotein C23 is a silver staining nucleolus organizer region (NOR) protein.

Journal ArticleDOI
TL;DR: Data in this report show that the contaminating proteins are skin proteins, especially keratins ranging from 54 to 57 kDa and 65 to 68 kDa.

Journal ArticleDOI
TL;DR: Gastric mucosal adaptation occurred and was associated both with less damage and with an accelerated healing process, and additional doses increased the area of involvement but not necessarily the severity of involvement.
Abstract: Endoscopy has become a standard method to evaluate drug-induced damage to the gastroduodenal mucosa; however, studies defining the time course, extent, and duration of the injury in man are unavailable. We report a systematic endoscopic evaluation of the effect of aspirin administration on the gastric mucosa in normal volunteers. Aspirin (2.6 g/day) or placebo was administered for 1 or 7 days. Gastroscopy was performed after 1, 2, 4, and 8 days, and every other day thereafter until the lesions resolved. Submocosal hemorrhages and/or focal erosions were present within 24 hr in all subjects. With continuous aspirin administration, injury was maximal within 3 days and then lessened, ie, damage present after 7 days of aspirin was significantly less than after 1 day of therapy. The time to resolution of the damage was also longer following 1 day than after 7 days of aspirin (median 8 days for 1 day of aspirin vs median 3 days for 7 days of aspirin). Thus, gastric mucosal adaptation occurred and was associated both with less damage and with an accelerated healing process. Acute administration of aspirin produced well-defined areas of submucosal hemorrhages within 2 hr of administration; additional doses increased the area of involvement but not necessarily the severity of involvement.

Journal ArticleDOI
TL;DR: A major difference between the effectiveness of ACTH and that of prednisone in stopping the spasms and improving the EEG pattern was not demonstrated and therapy was tapered and discontinued immediately after a response was obtained.

Journal ArticleDOI
TL;DR: PTFE grafts inserted in proximal extremity veins are excellent temporary conduits which decrease hemorrhage in blast cavities and fasciotomy sites, but all grafts studied by venography at 7 to 14 days were either narrowed or occluded.
Abstract: From 1978 through 1983, 206 patients had 236 polytetrafluoroethylene (PTFE) grafts inserted in vascular wounds. More than 85% of injuries were due to gunshot wounds, shotgun wounds, or stab wounds. Arterial grafts were inserted into vessels of the upper extremity (38.8%), lower extremity (46.1%), neck and chest (8.8%), and abdomen (6.3%). Grafts were most commonly placed in the brachial or superficial femoral arteries. Venous grafts were more commonly inserted into vessels of the extremities (96.7%), with the majority located in the superficial femoral vein. PTFE was found to be an acceptable prosthesis for interposition grafting in arterial wounds, but long-term patency was less than that seen when interposed saphenous vein grafts are used. Early and late occlusions were a significant problem with 4-mm PTFE grafts in the brachial artery, and this size is not recommended in this location. Peripheral PTFE graft infection did not occur in the absence of exposure of the graft or of osteomyelitis. Exposed grafts did not fare well and early coverage is recommended, even with extensive soft-tissue wounds around the graft. PTFE grafts inserted in proximal extremity veins are excellent temporary conduits which decrease hemorrhage in blast cavities and fasciotomy sites, but all grafts studied by venography at 7 to 14 days were either narrowed or occluded.

Journal ArticleDOI
TL;DR: Quantitative analysis of hourly ventricular arrhythmias prior to ventricular fibrillation revealed an increased frequency of premature ventricular beats and ventricular tachycardia, especially in the 2 hours immediately before ventricularfibrillation.

Journal ArticleDOI
TL;DR: It is concluded that bougienage is effective treatment for benign esophageal strictures, and should be utilized as primary therapy for most strictures.


Journal ArticleDOI
TL;DR: It is concluded that a hyperdynamic cardiovascular state occurs after severe head injury, and that it is mediated in part by sympathetic nervous activity.
Abstract: ✓ The cardiovascular, pulmonary, and metabolic responses to severe head injury were studied clinically in the acute phase after severe head injury with the object of determining if a common response was present and, if so, its significance in the management of the patients' intracranial and systemic physiological states. Cardiac output, pulmonary capillary wedge pressure, arterial blood pressure, arterial and mixed venous blood gases, and arterial and mixed venous epinephrine (E) and norepinephrine (NE) levels were measured serially in 15 patients during the first 3 days after injury. A hyperdynamic state was found, characterized by increased cardiac output, cardiac work, moderate hypertension, tachycardia, decreased or normal systemic and pulmonary vascular resistance, increased pulmonary shunting, and increased oxygen delivery and utilization. Arterial E and NE levels correlated well with the cardiac output, cardiac work, blood pressure, heart rate, oxygen delivery, and oxygen utilization but not with v...

Journal ArticleDOI
01 Nov 1983-Headache
TL;DR: In this article, a double-blind, cross-over, randomized assignment to high or low dose nimodipine therapy was performed on 35 headache patients with classic (n = 13), common (N = 14) migraine or cluster (N=8).
Abstract: SYNOPSIS Since Wolff's original proposal regarding the vascular etiology of cyclic head pain, evidence has accumulated that the prodromes of migraine are due to cerebral vasoconstriction and headaches of both cluster and migraine are due to painful dilatation. Theories regarding their pathogenesis include cyclic release of vasoactive substances from platelets and/or other sources (such as serotonin, catecholamines, histamine, acetyl choline, prostaglandins, substance P, endogenous opiates). These substances influence vasomotor receptors bringing about abnormal constriction and/or dilatation. Drugs which modify receptors (such as methysergide, alpha and beta blockers, antihistaminics, anticholinergics, steroids and non-steriodal anti-inflammatory agents) have had some therapeutic success in migraine but provide little benefit for cluster patients. Ca2+ entry blockers (including nimodipine, nifedipine, verapamil) theoretically should diminish cephalic vasoconstriction and -dilatation no matter what their cause. To test this, 35 headache patients with classic (N = 13), common (N = 14) migraine or cluster (N=8) were evaluated by double-blind, cross-over, randomized assignment to high or low dose nimodipine therapy. Within 10 days migraine prodromes became infrequent and after 2–4 weeks headache frequency was significantly reduced for migraine and within 4–6 weeks for cluster. CBF measurements during oxygen inhalation showed reduced cerebral vasoconstrictive responses after high dose nimodipine. Associated muscular contraction headaches were not altered. Nifedipine and verapamil provided equivalent relief for cluster but produced more side effects, and were less effective, than nimodipine in control of migraine.

Journal ArticleDOI
TL;DR: The present study has shown that there are many morphologically distinct kinds of aspiny GABAergic neurons in the visual cortex; that the predominant type of synaptic input to the dendrites of such neurons is from boutons forming asymmetrical synapses, but that some of the neurons also receive a dense symmetrical synaptic input on their cell bodies, and occasional synapses along their dendrite, from the boutons of other GABAergic neuron.

Journal ArticleDOI
01 Jan 1983-Cell
TL;DR: The calcium-dependent fusion of cultured rat myoblasts to multinucleate myotubes appears to require the activity of a neutral metalloendoprotease at the time of fusion, which is inhibited by the same compounds that prevent fusion.

Journal ArticleDOI
TL;DR: A latex agglutination test has been devised which allows detection of a circulating antigen in patients with systemic infection due to Candida albicans, Candida tropicalis and Candida parapsilosis and in all patients who recovered after antifungal therapy antigen levels returned to within the range found in normal controls.
Abstract: A latex agglutination test has been devised which allows detection of a circulating antigen in patients with systemic infection due to Candida albicans, Candida tropicalis and Candida parapsilosis. Latex is sensitized with serum from rabbits immunized with whole heat killed Candida albicans blastoconidia. The active component of this serum is IgG. Control latex, used to differentiate non-specific agglutination, is sensitized with the same dilution of serum from a rabbit without antibody to Candida species. Sera from a number of patient groups were tested. While none of the hundred normal controls had an antigen titer of greater than or equal to 1:4, 30 of 33 patients with documented disseminated candida infection had antigen titers of 1:4 to 1:32. Two of the 33 gave false negative results, and one caused nonspecific agglutination. In all patients who recovered after antifungal therapy antigen levels returned to within the range found in normal controls.