Showing papers by "Baylor College of Medicine published in 1981"
TL;DR: The silver-Staining procedure for detecting proteins in polyacrylamide gels has been modified and further simplified so that it is stable, controllable, and even more rapid than previous silver-staining methods.
3,476 citations
TL;DR: No studies have yet demonstrated that women on oral pills are at increased risk for growth of these tumors, and low-dose contraceptives should not be contraindicated in patients with leiomyomata if they desire to use this form of contraceptive.
1,455 citations
TL;DR: It is proposed that any substantial improvement in long-term survival must improve survival for the early period, and patients should be matched for hepatic functional reserve and identical zero time for calculating survival must be used.
880 citations
TL;DR: It is condude that EF can be determined accurately with 2‐D echo in a large group of patients with and without dyssynergy by a simple method that eliminates the need for planimetry or computer assistance.
Abstract: A new method to determine left ventricular (LV) ejection fraction (EF) with wide-angle, two-dimensional echocardiography (2-D echo) has been developed using the parasternal long-axis, apical four-chamber and apical long-axis views. End-diastolic and end-systolic measurements of LV short axes at the base and mid-LV cavity in the parasternal long-axis view and at the upper, middle and lower thirds of the cavity in the apical views are made, from which an averaged minor axis at end-diastolic and at end-systole is calculated. Fractional shortening of the LV long axis (delta L) is estimated from apical contraction. Satisfactory 2-D echoes were obtained in 55 of 58 nonselected patients (all three views in 32 patients, two views in 22 and one view in one); 42 of 55 patients had coronary artery disease. EF by 2-D echo was compared with EF by gated cardiac blood pool imaging in all patients (r = 0.927, SEE = 6.7%) and to EF by single-plane cineangiography (angio) in 35 of 55 patients (r = 0.913, SEE = 7.4%). LV dy...
724 citations
TL;DR: It is presented that each of these disorders is due to lack of a disorder‐specific neurotrophic hormone, and central nervous system tissue culture provides a convenient system in which to assay these neurotrophic hormones and should permit a test of the hypothesis.
Abstract: The causes of amyotrophic lateral sclerosis, Parkinson disease, and Alzheimer disease are unknown. Furthermore, treatment for two of these conditions is almost totally lacking. The thesis is presented that each of these disorders is due to lack of a disorder-specific neurotrophic hormone. The hormone would be elaborated or stored in the target of the affected neurons. It would be released by the postsynaptic cell and then exert its effects in a retrograde fashion after being taken up by the presynaptic terminal. In the lower motor neuron syndromes of amyotrophic lateral sclerosis, failure of muscle cells to release the appropriate motor neurotrophic hormone would result in impaired function of anterior horn cells. In Parkinson disease, the neurotrophic failure would be characterized by inability of striatal cells to provide the required dopamine neurotrophic hormone with resulting impairment of substantia nigra cells. In Alzheimer disease, the abnormalities would lie in failure of the hippocampus and cortical cells to supply the relevant cholinergic neurotrophic hormone with resulting impairment of medial septal and nucleus basalis neurons. Central nervous system tissue culture provides a convenient system in which to assay these neurotrophic hormones and should permit a test of the hypothesis.
696 citations
TL;DR: Protection against RS infection in early infancy that is correlated with the level of maternal antibody is demonstrated, but it is not known if this protection is mediated directly by the passively acquired antibody or by some other mechanism.
638 citations
TL;DR: This method detected a single adduct in 10(5) DNA nucleotides without requiring that the compound under investigation be radioactive and thus provides a useful test to screen chemicals for their capacity to damage DNA by covalent binding.
Abstract: Covalent adducts formed by the reaction of DNA with chemical carcinogens and mutagens may be detected by a 32P-labeling test. DNA preparations exposed to chemicals known to bind covalently to DNA [N-methyl-N-nitrosourea, dimethyl sulfate, formaldehyde, beta-propiolactone, propylene oxide, streptozotocin, nitrogen mustard, and 1,3-bis(2-chloroethyl)-1-nitrosourea] were digested to a mixture of deoxynucleoside 3'-monophosphates by incubation with micrococcal endonuclease (EC 3.1.31.1) and spleen exonuclease (EC 3.1.16.1). The digests were treated with [gamma-32P]ATP and T4 polynucleotide kinase (ATP:5'-dephosphopolynucleotide 5'-phosphotransferase, EC 2.7.1.78) to convert the monophosphates to 5'-32P-labeled deoxynucleoside 3',5'-bis-phosphates. These compounds were then separated on polyethyleneimine-cellulose thin layers in ammonium formate and ammonium sulfate solutions. Autoradiograms of the chromatograms obtained by this high-resolution procedure showed the presence of nucleotides derived from chemically altered, as well as normal, DNA constituents. Maps from DNA exposed to any of the chemicals used exhibited a spot pattern typical for the particular chemical. This method detected a single adduct in 10(5) DNA nucleotides without requiring that the compound under investigation be radioactive and thus provides a useful test to screen chemicals for their capacity to damage DNA by covalent binding.
513 citations
TL;DR: Neuronal cell bodies and synaptic terminals positive for glutamic acid decarboxylase, the enzyme responsible for synthesizing γ-amino butyric acid, have been located by immunocytochemical staining in all layers of the macaque monkey cortex.
Abstract: Neuronal cell bodies and synaptic terminals positive for glutamic acid decarboxylase, the enzyme responsible for synthesizing γ-amino butyric acid, have been located by immunocytochemical staining in all layers of the macaque monkey cortex. In layers II and III the staining pattern of periodic dots is identical with that seen in sections stained for cytochrome oxidase. The rows of dots run parallel with the ocular dominance columns, suggesting that the labelled neurones are preferentially related to each eye.
321 citations
TL;DR: In the Houston Family Study, young children were cultured for virus weekly or biweekly and during acute respiratory illnesses and the interval between the onset of illness and positive culture was examined for 179 infections during 1975-1979.
Abstract: In the Houston Family Study, young children were cultured for virus weekly or biweekly and during acute respiratory illnesses. The interval between the onset of illness and positive culture was examined for 179 infections during 1975-1979. In week 1 after onset, 73%, 73%, and 66% of cultures were positive for influenza A virus, respiratory syncytial virus (RSV), and parainfluenza virus type 3, respectively. Pooled data from influenza B virus infections in 1977 and 1980 showed that 73% of cultures were positive in week 1. Influenza A virus in week 2 or RSV in weeks 2 and 3 was isolated from very few children. However, 37% of cultures were positive for influenza B virus during week 2, and 17% of cultures were still positive for parainfluenza virus type 3 during week 3. Shedding of parainfluenza virus type 3 on days 29-38 was also observed. Parainfluenza virus type 3, RSV, and influenza A virus were isolated up to six days before the onset of illness.
241 citations
TL;DR: In this article, the authors used first-pass radionuclide angiocardiography to assess filling fraction during the first third of diastole, peak filling rate and peak filling rates in patients with coronary artery disease.
Abstract: We used first-pass radionuclide angiocardiography to assess filling fraction during the first third of diastole, peak filling rate and peak filling rate during the first third of diastole as indexes of left ventricular diastolic performance at rest and after upright bicycle exercise in 32 normal patients and 68 patients with coronary artery disease. The mean filling fraction was unchanged from rest to exercise in normal patients (47+/- 15% vs 46 +/- 13%; NS). Even in 49 coronary patients with normal (greater than or equal to 50%) ejection fraction at rest, filling fraction was less than that in normal patients at rest (35 +/- 11% vs 47 +/- 15%, p less than 0.001). Despite similar resting heart rates, patients with coronary disease had lower (p less than 0.001) peak filling rate and peak filling rate during the first third of diastole than normal patients. With exercise, filling fraction decreased (p less than 0.001) from the resting value in coronary patients. These data suggest that (1) indexes of diastolic performance can be noninvasively assessed at rest and during exercise using first-pass radionuclide angiocardiography, (2) abnormalities in early diastolic performance are often present at rest in patients with coronary artery disease despite normal systolic performance, and (3) exercise-induced ischemia results in increased early diastolic dysfunction in patients with coronary disease.
233 citations
TL;DR: Results indicated that intact ribosomal RNA (rRNA) can be obtained from purified cells, and both cell types are active in synthesizing presumptive messenger RNA (mRNA) with a wide range of sedimentation values, but no appreciable rRNA synthesis was detected.
Abstract: A method forobtaininghighlypurifiedfractions of rat testicular cells is described. Single cell suspensions from adult rat testes were separated by centrifugal elutriation. Fractions enriched in pachytene primary spermatocytes, early spermatids, and cytoplasts detached from late spermatids were obtained. These fractions were further separated by equilibrium density centrifugation on gradients of Percoll. In this manner fractions of 3 X 10� pachytene spermatocytes (98% purity), 1.1 X 10� early spermatids (93% purity), and 1.1 X i05 cytoplasts (98% purity) were obtained within 6 h after sacrificing the rats. The cells appeared to be morphologically intact and to have retained their biochemical integrity. Analysis of acid-soluble nuclear proteins by polyacrylamide gel electrophoresis showed that histone 4 is synthesized during the pachytene stage, and confirmed that testis-specific histones are also synthesized during this stage. Analysis of a microsomal RNA preparation from purified pachytene spermatocytes and purified early spermatids by sucrose gradients indicated that intact ribosomal RNA (rRNA) can be obtained from purified cells. Both cell types are active in synthesizing presumptive messenger RNA (mRNA) with a wide range of sedimentation values, but no appreciable rRNA synthesis was detected.
TL;DR: Biological and biochemical studies of tsJ12 and of a ts+ revertant of this mutant demonstrate that glycoprotein gB is essential for infectivity at the level of penetration and further define the physical map location of the gene for this glycop protein.
TL;DR: The lesions of C2 seen in hyperextension injuries of the cervical spine following motor vehicle accidents, diving accidents, and headlong falls resemble the cervical lesion found in judicial hangings.
Abstract: A series of 123 patients suffering traumatic spondylolisthesis of the axis is reported. This lesion is associated with extension and axial loading injury, and there is a high incidence of injuries of the face or scalp and of associated fractures of the upper cervical spine. There is a low incidence of neurological injury, which seems paradoxical in the presence of what appears to be gross instability, but protection from extremes of flexion and extension may be adequate treatment. Union is usual regardless of displacement. Traction is a safe means of treatment, but early waking in a halo support reduces time in hospital without jeopardizing the result. Operation is needed only for chronic instability with or without pain, and anterior interbody fusion of C2--3 is than preferred in order to preserve rotation at the atlanto-axial joints.
TL;DR: Earlier observations suggesting the correlation between low levels of type-specific antibody in serum and risk for systemic infection with type III strains of group B streptococci are extended are extended.
Abstract: The role of maternally acquired antibody to native type III polysaccharide of group B Streptococcus as a determinant of susceptibility for infant systemic infection was investigated. Sera from 111 acutely ill infants with type III group B streptococcal bacteremia and/or meningitis and their mothers, and cord sera from 45 healthy neonates and their mothers who had type III group B streptococcal vaginal colonization at delivery were studied. Sera from each of 111 acutely ill infants contained very low levels of antibody (less than 1.7 microgram/ml, median 0.4 microgram/ml), and a significant correlation with maternal levels was tested for early onset infection (median 0.6 microgram/ml; 4 = .76; P less than .01). Women whose infants remained well had antibody levels greater than 2 microgram/ml in their sera (73%) more often than those whose infants developed symptomatic infection (17%) (P less than .001), and the median level in their sera (12.6 microgram/ml) was considerably higher. Study of sera obtained during convalescence from 86 surviving infants indicated a poor antibody response to infection. In contrast, high levels of antibody were detected in sera from each of five convalescent women with postpartum bacteremia. These data extend earlier observations suggesting the correlation between low levels of type-specific antibody in serum and risk for systemic infection with type III strains of group B streptococci.
TL;DR: In this article, an atmospheric pressure ionization (API) mass spectrometer is used to detect positive or negative ions present in a reaction chamber, which is maintained at atmospheric pressure.
Abstract: Atmospheric pressure ionization (API) mass spectrometry is a novel form of mass spectrometry in which the ionization process is carried out in a reaction chamber external to the mass analyzer region. The mass analyzer serves as a device to detect positive or negative ions present in the reaction chamber, which is maintained at atmospheric pressure.
TL;DR: It is concluded that long-term status was difficult to predict, but SVT was present in fewer patients whose age at onset was less than 4 months and in those with unoperated CHD, and early recurrence was not a poor prognostic sign.
TL;DR: In an outbreak of influenza virus A/England/333/80(H1N1) infections in college students, 14 randomly selected patients were treated by inhalation of ribavirin small-particle aerosol through a face mask to achieve a therapeutic effect.
TL;DR: In this paper, a prospective survey of ophthalmic manifestations of neurofibromatosis (NFT) has been conducted and the results of the survey have not been published.
TL;DR: The successful management of suppurative microbial keratitis requires five steps: to make the clinical diagnosis, to perform the proper laboratory procedures, to initiate antimicrobial therapy, to modify the initial therapy, and to terminate therapy.
TL;DR: The behavior of methadone-treated women during pregnancy and the postnatal period closely resembled that of drug-free controls, and contrasted with untreated drug-dependent women.
TL;DR: The results are consistent with the notion that the specification of microtubule length, number, and spatial arrangement resides largely in the MTOCs and surrounding cytoplasm and not in the tubulin subunits.
Abstract: The number, distribution, and nucleating capacity of microtubule-organizing centers (MTOCs) has been investigated in a variety of cultured mammalian cells. Most interphase cells contain a single MTOC that is localized at the centrosome region and corresponds to the centriole and pericentriolar material. MTOCs, like centrioles, become duplicated during the S phase of the cell cycle and are equationally distributed to daughter cells in mitosis. Multiple MTOCs were rarely observed in cultured cells except in one cell line (neuroblastoma), which also displayed an equally large number of centrioles in the cytoplasm. The kinetics of microtubule assembly and the tubulin nucleating capacity of MTOCs was assayed by incubating tubulin-depleted, permeabilized 3T3 and simian virus 40-transformed 3T3 cells with phosphocellulose-purified 65 brain tubulin and microtubule assembly buffer. Initiation and assembly of 65 tubulin occurred in association with the cells' endogenous MTOCs, and the length, number, and distribution of microtubules generated about the organizing centers were regulated and cell specific. Our results are consistent with the notion that the specification of microtubule length, number, and spatial arrangement resides largely in the MTOCs and surrounding cytoplasm and not in the tubulin subunits.
TL;DR: Findings indicate that predisposition to retinoblastoma may be attributed to the loss of specific genetic material and that a chromosomal mechanism may explain apparent lack of gene penetrance in certain families.
Abstract: Surviving persons from a kindred in which retinoblastoma occurred over four generations, transmitted by eight unaffected individuals, underwent chromosomal analysis. The results revealed that the development of retinoblastoma was associated with a constitutional chromosome deletion del(13)(q13.1q14.5) and that the unaffected transmitting state was associated with a balanced insertional translocation. These findings indicate that predisposition to retinoblastoma may be attributed to the loss of specific genetic material and that a chromosomal mechanism may explain apparent lack of gene penetrance in certain families. The development of unilateral, and not bilateral, retinoblastoma suggests either that the chromosome deletion is different from the mutation of heritable retinoblastoma in general, or that the chromosome deletion lessens the probability of subsequent somatic carcinogenic events.
TL;DR: Compared to Neisseria meningitidis groups A and C, group B strains appear to be intermediate in their potential for allergic complications associated with childhood infection.
TL;DR: Objective recovery of the FR has not been observed after treatment in spite of the subjective improvement in the sensation of dryness of some patients, and there is some relation between the initial FR and the dose necessary to produce dryness: patients with high initial salivary FR require higher doses.
Abstract: Salivary flow rate (FR) was studied in 29 patients treated with external irradiation to bead and neck areas. “Resting” saliva samples were collected before, during the radiotherapy course and follow-up. Several parameters were investigated: field arrangement, amount of salivary glands irradiated, dose to these glands, initial FR, its recovery during and after irradiation, and influence of therapy interruption (split course) in FR. We found that the level of the upper border of the field is a critical factor when using parallel-opposed lateral fields to the upper neck area and lateral face. More than 50% of the parotids have to be outside the fields to prevent severe dryness. Neck fields which do not encompass salivary glands do not decrease salivary secretion. There is some relation between the initial FR and the dose necessary to produce dryness: patients with high initial salivary FR require higher doses. FR recovery occurs during weekend interruptions before xerostomia develops. Interruptions of therapy for more than two weeks during the radiotherapy course prior to development of dryness might decrease late xerostomia, at least in patients with high initial FR. Objective recovery of the FR has not been observed after treatment in spite of the subjective improvement in the sensation of dryness of some patients.
TL;DR: Protein C23 was found in ‘fibrillar centers’ (nucleolonemas) in nucleoli and demonstrated to be present on the nucleolus organizer regions (NORs) of metaphase chromosomes in Novikoff hepatoma nucleoli.
TL;DR: Protein A, a constituent of the cell wall of Staphylococcus aureus Cowans 1 (SpA), reacts with the Fc region of immunoglobulins from many mammalian species and combines with immune complexes in ser…
Abstract: PROTEIN A, a constituent of the cell wall of Staphylococcus aureus Cowans 1 (SpA), reacts with the Fc region of immunoglobulins from many mammalian species and combines with immune complexes in ser...
TL;DR: The factors that seem most significant in creating excessive postoperative astigmatism are delineated and the difficulty of creating a circular recipient hole of the same size and shape as the donor button appears to be a prime area for clinical research and technical development.
TL;DR: Results from a specific precipitating antibody against chicken gizzard myosin light chain kinase (MLCK) in rabbits are consistent with the suggestion that MLCK and calmodulin are intermediates in the regulation of cell motility by calcium.
TL;DR: Using DNAase l-Sepharose chromatography, a protein fraction is isolated whose binding to actin is Ca2+ -dependent, which increases the rate of development of high sheer viscosity, but lowers the final value if Ca22+ is present.