Origin of the HIV-susceptible human CD4+ cell line H9.
Explore the source record for details and available documents.
CD4-Positive T-Lymphocytes↗
Biomedical subjects
D L Mann
Publications and source records attributed to D L Mann.
Alkyl and aryl carcinogen adducts detected in human peripheral lung.
Human peripheral lung tissue samples were obtained at autopsy from 17 individuals of known occupational and smoking histories. A spectrum of different carcinogen-DNA adducts was detected using a variety of sensitive techniques. High-pressure liquid chromatography-linked synchronous fluorescent spectrophotometry and an ultrasensitive enzyme radioimmunoassay detected adducts derived from benzo[a]pyrene diol epoxide and other apparent polycyclic aromatic hydrocarbons. An amplified enzyme-linked immunosorbent assay demonstrated the presence of 4-aminobiphenyl-DNA adducts in many of these samples. A number of these specimens also contained O6-alkyldeoxyguanosine as measured by 32P-postlabeling techniques. Thus this pilot study indicates not only that human lung contains a spectrum of carcinogen-DNA adducts, but also that a full scale molecular dosimetry study of human exposure to both aryl and alkyl chemical carcinogens is warranted.
Adolescent↗
Fluorescence and mass spectral evidence for the formation of benzo[a]pyrene anti-diol-epoxide-DNA and -hemoglobin adducts in humans.
Highly specific methods are required to detect and quantitate carcinogen-macromolecular adducts in humans who are exposed to complex mixtures of chemical carcinogens. High performance liquid chromatography and fluorescence spectroscopy have been used successfully to detect and identify residues of benzo[a]pyrene-7,10/8,9-tetrahydrotetrol (BP-7,10/8,9-tetrol) that were released upon mild acid hydrolysis of human DNA or hemoglobin. Synchronous fluorescence spectroscopy data indicate that levels of benzo[a]pyrene-diol-epoxide-DNA (BPDE-DNA) adducts as high as 1.54 fmol BPDE/micrograms DNA are formed (1 adduct in 5 million nucleotides) in peripheral blood lymphocytes of coke-oven workers; these data were subsequently corroborated by gas chromatography/mass spectroscopy single ion monitoring analysis (m/z 404+). Additionally, among lung cancer patients, 5 samples of tumor DNA were found to be negative and 1 of 4 samples of corresponding lung tissue was found to be positive. Extraction and purification of BP-7,10/8,9-tetrol from the hemoglobin of smokers suggested levels of bound carcinogen in excess of 1 ng BPDE/gm of hemoglobin. High performance liquid chromatography combined with synchronous fluorescence spectroscopy provides a highly specific method for the detection of covalently bound BP residues in both human hemoglobin and DNA.
Benzo(a)pyrene↗
Contractile function of isolated feline cardiocytes in response to viscous loading.
The classical force-velocity relationship is a standard measure of the contractile function of isolated linear cardiac muscle, but no such simple index of contractile function exists for the isolated mammalian cardiocyte. Therefore, this study established an analogous viscosity-velocity relationship for the characterization of cardiocyte contractile function. For this purpose, force was imposed on unfettered adult feline cardiocytes as a series of defined viscous loads, which provided resistance to cardiocyte shape changes during contraction. This was done by increasing the viscosity of the Krebs superfusate (37 degrees C, pH 7.4) in graded, reproducible steps from 1 to 500 centipoise by the addition of methylcellulose. Sarcomere motion within each contracting cardiocyte was measured as movement of the diffraction pattern cast onto a photodiode array by a laser beam passing through the cell. Both the rate and extent of sarcomere shortening varied inversely with increasing viscosity, whereas neither resting sarcomere length nor osmolarity was altered. Further, increased inotropism effected by paired-pulse stimulation of cardiocytes caused an upward shift of the entire viscosity-velocity relationship. Thus the cardiocyte viscosity-velocity relationship is analogous in form to the force-velocity relationship of isolated linear cardiac muscle and provides a simple reproducible method for characterizing the contractile performance of relatively large numbers of cardiocytes isolated from a single specimen of myocardium.
Animals↗
Load regulation of the properties of adult feline cardiocytes: growth induction by cellular deformation.
Previous studies from this laboratory have demonstrated rapid and reversible changes in cardiac structure, composition, and function in response to load alterations in vivo. The purpose of the present in vitro study was to examine directly in the isolated, quiescent adult cardiocyte the potential growth-regulating effects of load changes through the use of an extremely simple and well-defined cell culture preparation. Freshly isolated cardiocytes were plated onto a deformable, laminin-coated substrate and maintained in serum-free culture medium for 3 days. On the third day in culture, the resting length of these quiescent cardiocytes, and thus their external load, was increased by linear deformation of the substrate to which these cells were firmly adhered. Cardiocyte loading resulted in increases of approximately 10% in cell length, approximately 8% in cell surface area, and approximately 7% in sarcomere length. Three markers of increased synthetic activity were then examined: 1) [3H]uridine incorporation into nuclear RNA, 2) [3H]phenylalanine incorporation into cytoplasmic protein, and 3) [3H]thymidine incorporation into DNA. Cardiocyte loading resulted in mean increases of 186% in nuclear RNA labeling and 89% in cytoplasmic protein labeling. The finding that the increase in [3H]phenylalanine incorporation could be blocked readily by cycloheximide showed that the increase in cytoplasmic labeling in response to cardiocyte loading was not simply the result of increased amino acid transport but instead resulted from the incorporation of label into newly synthesized protein. An absence of [3H]thymidine nuclear incorporation in the loaded cardiocytes indicated that DNA synthesis was not activated in these cells. These data constitute the initial demonstration that an increase in load is at least a sufficient stimulus for the induction of increased RNA and protein synthetic activity in the adult mammalian cardiocyte. This evidence for the role of load as an independent regulator of cardiac growth in the adult suggests that hemodynamic changes may lead directly to appropriate alterations in cardiac structure and composition through the transduction of this physical stimulus into one or more biochemical signals that modulate gene expression.
Animals↗
Association of cigarette smoking with decreased numbers of circulating natural killer cells.
To investigate the relationship between cigarette smoking and the level of circulating natural killer (NK) cells, we studied 282 subjects from a population-based, stratified random sample of healthy persons. NK cells were enumerated by flow cytometry using the monoclonal antibody anti-Leu 11A. Cigarette smokers had a significantly lower proportion of NK cells than did subjects who had never smoked (5.5 +/- 0.3% versus 7.4 +/- 0.4% of lymphoid cells; p = 0.0002). NK cells were also decreased among ex-smokers (5.6 +/- 0.4%; p = 0.002), including subjects who had not smoked for more than 20 yr. The white blood cell and lymphocyte counts were increased in smokers compared with those in never smokers (p less than 0.0001). In contrast to NK cells, the smoking-related changes in leukocyte count were not present in ex-smokers, even those who had stopped smoking within the past year. Multivariate analysis confirmed that both current and past smokers had significant decreases in both the number and proportion of NK cells after controlling for age, sex, and lymphocyte count. These data indicate that cigarette smoking is associated with a decrease in the number and proportion of circulating NK cells, and that this effect is present many years after smoking cessation. This quantitative NK cell deficit may contribute to the elevated risk of malignancy in this population.
Adult↗
The effects of cigarette smoking on T cell subsets. A population-based survey of healthy caucasians.
To investigate the influence of cigarette smoking on mononuclear cell subsets, we determined T cell, B cell, monocyte, and HLA-DR+ subsets in a population-based, stratified, random sample of healthy Caucasians using monoclonal antibodies and flow cytometry. The study population consisted of 282 subjects 20 to 69 yr of age, including 108 smokers and 174 nonsmokers. Multivariate analysis techniques were used to assess the influence of cigarette smoking status after controlling for the effects of age and gender. Cigarette smoking was associated with a nonspecific increase in the leukocyte count involving all major cell types (smokers: 8.50 +/- 0.15 versus nonsmokers: 7.33 +/- 0.12 cells/mm3; p less than or equal to 0.0001). In addition, cigarette smokers had a selective increase in CD4+ cells (helper-inducer T cells) compared with nonsmokers (55.3 +/- 0.8 versus 52.2 +/- 0.6% of lymphoid cells; p = 0.002), resulting in a statistically significant increase in the CD4+/CD8+ (helper/suppressor) ratio (2.42 +/- 0.1 versus 2.13 +/- 0.16; p = 0.02). There was no significant difference between smokers and nonsmokers in the level of CD3+ cells (total T cells: 76.8 +/- 0.7 versus 76.1 +/- 0.5; p = 0.5), CD8+ cells (suppressor-cytotoxic T cells: 25.7 +/- 0.8 versus 27.0 +/- 0.5%; p = 0.1), CD19+ cells (B cells) (10.7 +/- 0.4 versus 10.0 +/- 0.3%; p = 0.2), CD14+ cells (monocytes) (18.0 +/- 0.6 versus 17.0 +/- 0.4%; p = 0.2), or HLA-DR+ cells (14.5 +/- 0.5 versus 14.0 +/- 0.4%; p = 0.4).(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Reversion of mitral valve preclosure in acute aortic insufficiency secondary to infective endocarditis.
A 59-year-old man presented with culture-negative endocarditis. Serial echocardiographic/Doppler studies disclosed progressive aortic insufficiency with resultant premature closure of the mitral valve. At the time the patient developed PMVC he was considered for emergent aortic valve replacement; ultimately, however, he was deemed inoperable because of his underlying medical problems. Surprisingly, the patient gradually improved on antibiotic therapy alone, with subsequent hemodynamic stabilization and reversion of the PMVC. This case represents the first description of reversion of PMVC in a medically treated patient with severe aortic insufficiency secondary to infective endocarditis, and underscores the importance of basing management decisions concerning aortic valve replacement in infective endocarditis upon the entire constellation of clinical findings rather than a single echocardiographic sign.
Aortic Valve Insufficiency↗
Shoulder injuries in archery.
Twenty-one elite-calibre archers (M = 12, F = 9) were investigated concerning all past and present archery-related shoulder injuries, using a questionnaire and physical examination. The questionnaire revealed that 11 of 21 archers had complained of significant shoulder injuries either currently or during their careers. While 9/12 men never had shoulder problems during an average of 13.5 years, only 4/9 women escaped injury during a mean 10.9 year competitive career. Deficits in training programs were noted, including lack of training and non-specific exercises. Clinical examination demonstrated shoulder asymmetry and decreased flexibility in the drawing arm (DA) shoulder. Functional testing revealed a positive impingement sign in 6/21 DA shoulders. Supraspinatus testing showed abnormalities in 4/21 DA shoulders. Pain was referred posteriorly with the impingement maneuver in 5/21 DA shoulders and abnormal external rotation testing was observed in 8/21 DA shoulders. Generally, the females had proportionally more signs and symptoms of shoulder injury than the men, especially involving the DA shoulder. Testing implicated supraspinatus impingement/tendonitis and infraspinatus/teres minor traction tendonitis. These clinical findings correlated with cadaver prosection observations.
Acromion↗
HLA-DR is involved in the HIV-1 binding site on cells expressing MHC class II antigens.
The primary interaction of HIV-1 with the target cell involves the viral large envelope protein (gp120) and the cellular CD4 molecule. mAb reacting with portions of CD4 have been shown to block HIV-1 attachment and infection. In one of the early reports describing HIV-1 cell interaction, some mAb reacting with MHC class II Ag were also found to block infection. To investigate further a possible role for MHC class II in HIV-1 binding, a cultured T lymphocyte cell line (H-9) that expresses MHC class II molecules and PHA-stimulated PBL was exposed for various time periods to concentrated viral particles and individual HIV-1 proteins. A decrease in the ability to detect the CD4a epitope and HLA-DR was observed after the cells were exposed to virus for 15, 30, and 60 min whereas HLA-DP and HLA-DQ Ag increased or remained unchanged. After 120 min of virus exposure, the CD4a epitope remained diminished whereas HLA-DR was detected at levels found on cells not exposed to virus. mAb detecting the CD4a epitope and HLA-DR, as well as alloantisera detecting the specific HLA-DR Ag on the target cell, blocked HIV-1 binding. When immunopurified gp120 was added to PHA-stimulated and unstimulated PBL, the CD4a epitope decreased in the same manner as was observed with whole virus preparations. In contrast to exposure to the intact virus, HLA-DR expression appeared to increase. Other viral proteins, p17, p24, and a portion of the small envelope protein, gp41, had no effect on the ability to detect cell surface Ag. Thus, although CD4 is the primary receptor for HIV-1 binding, HLA-DR appears to be involved in the binding site, probably by virtue of its close proximity to the CD4 molecule on the cell surface.
Antibodies, Monoclonal↗
Lymphoma-specific T- and B-cell responses suggest the involvement of HTLV-I in virus-non-productive lymphomas of a married couple.
In a married couple, a T-cell and a B-cell lymphoma occurred at the same time in the husband (FR) and wife (FE), respectively. Serum antibodies of patient FE with less advanced tumor progression specifically recognized HTLV-I-related envelope precursor molecules of 66-68 kDa molecular mass on HTLV-I-infected T- and B-cell lines, but not on HTLV-II or HIV-infected cells. In addition, in vivo-activated CD8+ T-cell lines (TCL) from this patient specifically lysed autologous B-lymphoma cells, T-lymphoma cells from the husband (FR), as well as the HTLV-I-transformed MT2 T-cell line. All positive target cells shared an HLA-class-I cross-reactive determinant identified by the alloantiserum WER127. On a clonal level, the specificity of the cytotoxic T-cell response was unequivocally distinguishable from classical natural-killer-like cytotoxicity. Results imply the involvement of a common inductive agent in the manifestation of malignant lymphoma in both patients (FR and FE). Since antibodies from cases with classical HTLV-I-induced adult T-cell leukemias (ATLL) did not bind antigens on cells of either lymphoma (FR or FE) and active virus production was not demonstrable under various different conditions, these results argue against HTLV-1 itself being the transforming agent. However, humoral and cellular immune responses of one patient (FE), in addition to de novo HLA-class-1 antigen expression of both patients, are nonetheless consistent with the involvement of viral infections(s). These were responsble for the expression of HTLV-1-characteristic envelope determinants of the malignant progeny of respective T- and B-cell origin.
Aged↗
Early natural history of regional left ventricular dysfunction after experimental myocardial infarction.
Existing studies provide conflicting information concerning the natural history of regional dysfunction after subacute myocardial infarction. The purpose of this study was to use quantitative computer-assisted two-dimensional echocardiography to define the natural history of abnormal wall motion in a subacute canine infarct model within individual short-axis echocardiographic planes, and in the entire ventricle as well. Serial short-axis echocardiograms were obtained from 10 closed-chest dogs before occlusion and at 0.5, 6, 24, 48, and 72 hours after ligation of the circumflex (six dogs) or left anterior descending (four dogs) coronary artery. The circumferential extent of abnormal wall motion was quantified by two different computer-assisted methods: the first, a derived correlation method, examined wall motion throughout the systolic contraction sequence; the second method examined the fractional radial change in endocardial ray length from end-diastole to end-systole. The study shows that for individual planes there is a slight but not statistically significant increase in the circumferential extent of abnormal wall motion from 0.5 to 72 hours after coronary artery occlusion; however, when the total extent of left ventricular asynergy was used to define a global functional infarct size, we observed a small (3.6% to 5.4%) but significant increase in the circumferential extent of abnormal wall motion.
Analysis of Variance↗
Detection of benzo[a]pyrene diol epoxide-DNA adducts in human placenta.
Human placenta is a readily available organ that responds to maternal environmental insult and has been previously used to investigate metabolism and bioactivation of procarcinogens, for example, benzo[a]pyrene. HPLC in combination with synchronous fluorescence spectroscopy was used to examine 28 placentas for the presence of benzo[a]pyrene diol epoxide-DNA adducts, and 10 of these were found to be positive. DNA samples from these placentas were subsequently pooled and subjected to partial enzymatic digestion to oligonucleotide fragments. Concentration of those DNA fragments containing benzo[a]pyrene diol epoxide-DNA adducts was achieved by immunoaffinity chromatography with polyclonal antibodies raised against these adducts. Column eluates were hydrolyzed under mild acid conditions and extracted with an organic solvent. The presence of benzo[a]pyrene-7,10/8,9-tetrahydrotetrol residues in the extracts was determined by HPLC and synchronous fluorescence spectroscopy and was confirmed by GC/MS. The results unequivocally confirm bioactivation and formation of DNA adducts from benzo[a]pyrene in human placenta in vivo and establish a methodological approach to direct measurement of carcinogen-DNA adducts that are formed as a result of human environmental exposure.
7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗
Langerhans' cells are an actual site of HIV-1 replication.
Human epidermal Langerhans' cells (LC) are HLA-DR+/DQ+, CD1+, CD4+ dendritic antigen-presenting leukocytes. Based on the observation that in certain human immunodeficiency virus type 1 (HIV-1) infected individuals, LC are the only epidermal cells to react with monoclonal antibodies against HIV-1 isolate termed human T-lymphotropic virus IIIB/83 core proteins p17 and p24, we have proposed that LC can serve as a target for HIV-1. This contention was strengthened by the ultrastructural finding of HIV-1-like particles in the close proximity of LC and by the demonstration of signs of moderate to severe LC damage. Detailed electron microscopic analysis of skin and mucosal biopsies from an AIDS patient with p17/p24-positive LC now revealed not only mature HIV-1-like virions in the extracellular space surrounding LC and in intracytoplasmic LC vacuoles, but also developmental forms of HIV-1-like particles budding from LC surface membranes. Using peripheral blood derived monocytes/macrophages as targets for HIV-1 isolation, a virus isolate, designated human T-lymphotropic virus III WR-SK/86, was recovered from skin tissue from this patient by cocultivation and identified as unique by nucleic acid hybridization analysis. These findings now conclusively show that HIV-1 replicates in and is released from LC and support the concept that antigen-presenting cells (mononuclear phagocytes, LC) can serve as a reservoir for the acquired immunodeficiency syndrome virus.
AIDS-Related Complex↗
Detection and characterization of human serum antibodies to polycyclic aromatic hydrocarbon diol-epoxide DNA adducts.
The presence of serum antibodies to the diol-epoxide DNA adducts of representative polycyclic aromatic hydrocarbons (PAH), chrysene, benz[a]anthracene and benzo[a]pyrene, was determined by ELISA using serum samples obtained from normal healthy individuals. Antibodies that reacted against PAH adducted-DNA, but not against PAH-adducted protein, were found in the serum of approximately 40% of the test individuals. Specificity analysis of the antibodies demonstrated that serological cross-reactions between the benzo[a]pyrene and the chrysene diol-epoxide adducts were present. Similar cross-reactivity between the benz[a]anthracene and the chrysene adducts was observed. Sera containing antibodies that were apparently specific for each of the three PAH-DNA adducts were also identified. The presence of antibodies to PAH-DNA adducts indicates both past exposure to these carcinogenic PAH and their metabolic activation to the DNA damaging metabolites. These antibodies may prove to be useful in both retrospective and prospective epidemiological studies of various diseases associated with PAH exposure.
Adult↗
Tarsal coalition: a review of the literature and presentation of 13 cases.
Tarsal coalition refers to the condition that exists when there is absent or restricted movement between two or more of the bones of the hindfoot. The usual cause of the restricted movement is a congenital abnormality with a fibrous (syndesmosis), cartilagenous (synchondrosis), or bony (synostosis) union between the adjoining involved bones. The commonest site of these congenital anomalous attachments are reported in the literature as being located at the calcaneonavicular, the talocalcaneal, and, less commonly, the talonavicular areas. Limited movement in the hindfoot can also result from trauma, arthritis, tumor, or injury involving those joints in the foot. The congenital form may often go unrecognized until such time as a twist or sprain of the ankle or foot leads to its diagnosis. On the other hand, the condition may go unrecognized as a cause for chronic pain or discomfort in the hindfoot or ankle. In this article, a series of 13 feet in 11 patients with this condition that have been noted in the sports medicine clinic at the University of Arizona Health Sciences Center during the past 8 years is described. A detailed historical, clinical, and biomechanical account is also included.
Adolescent↗
DNA restriction fragment length polymorphisms at either end of the c-raf-1 locus at 3p25.
We report the identification and characterization of two restriction fragment polymorphisms (RFLPs) associated with the human c-raf-1 protooncogene located on chromosome 3 (3p25). EcoRI digestion produces an RFLP derived from the 5'flanking sequences with a heterozygosity of 28%, and TaqI produces an RFLP representing the 3' flanking sequences with a heterozygosity of 25%. The finding of RFLPs associated with a potential oncogene may provide a method of analysis for determining genetic susceptibilities to certain cancers.
Chromosome Mapping↗
raf protooncogene expression in neural and immune tissues.
Explore the source record for details and available documents.
Animals↗