PubMed Health⌕ Search

Biomedical subjects

J S Miller

Publications and source records attributed to J S Miller.

At least 19 recordsLinked to original sources
PubMed1992

The generation of human natural killer cells from CD34+/DR- primitive progenitors in long-term bone marrow culture.

We have adapted the stroma-dependent long-term bone marrow culture (LTBMC) system to study the development of human natural killer cells (NK) from the CD34+/HLA-DR- (CD34+/DR-) BM mononuclear cell (BMMNC) population. The CD34+/DR- population does not express any known antigens associated with myeloid or lymphoid lineage and has been shown by us and others to contain primitive hematopoietic progenitors capable of both self-renewal and differentiation to myeloid lineage. CD34+/DR- cells obtained from normal human BM by fluorescence-activated cell sorting were plated on allogeneic, irradiated BM stromal layers. After 5 weeks of culture in the presence of media containing recombinant interleukin-2 and human serum, 147- +/- 21-fold expansion of cells with the morphologic appearance of large granular lymphocytes was observed. Cultured cells (84.8% +/- 1.5%) expressed the characteristic CD56+/CD3- phenotype of NK. A proportion of CD56+/CD3- cells expressed other markers of lymphoid lineage that have been associated with mature NK, including CD2 (7.8% +/- 1.2%), CD7 (19.5% +/- 2.8), CD8 (3.1% +/- 1.0%), and CD16 (4.5% +/- 1.3%). The cultured cells did not express other antigens associated with T-lymphocyte (CD3, CD5, T-cell receptor [TCR] alpha/beta and TCR gamma/delta), B-lymphocyte (CD19), myeloid (MY8, CD33, and CD71), or monocytoid (CD14 and CD15) lineage and did not express the CD34 antigen associated with hematopoietic progenitors present on the starting population. This NK population was cytotoxic against both K562 (E:T 20:1; 79% +/- 1.9%) and Raji (E:T 20:1; 38% +/- 5.7%) target cell lines. The NK progenitor frequency in the CD34+/DR- cell population determined by limiting dilution of CD34+DR- on stromal layers followed by a functional chromium release assay against K562 targets was 1:169 +/- 50 CD34+/DR- cells. The data suggest that human LTBMC developed to study myeloid differentiation can be modified to study the origin and development of the NK and possibly other lymphoid lineages. Modified cultures show that cells with morphologic, phenotypic, and functional characteristics of NK can be derived from a population of BMMNC with the phenotype of primitive hematopoietic progenitors and without phenotypic evidence of lymphoid- or myeloid-lineage commitment. Further studies will address the cell of origin and the ontogeny of human NK and other lymphoid lineages.

Adult↗
PubMed1992

Role of monocytes in the expansion of human activated natural killer cells.

We have studied the mechanisms underlying expansion of recombinant interleukin-2 (rIL-2)-stimulated natural killer (NK) cells in vitro. A population of NK cells expressing the CD56+/CD3-phenotype (98.9% +/- 0.42%) was obtained from normal human peripheral blood mononuclear cells (PBMNC) by fluorescence-activated cell sorting (FACS). Culture of NK cells in media containing rIL-2 (1,000 U/mL) for 18 days resulted in a population of activated NK cells (ANK) with significantly enhanced cytotoxicity, but only 2.6 +/- 0.56-fold expansion of cell number compared with the starting NK population. Culture of starting NK populations and autologous PBMNC in a Transwell system (Costar, Cambridge, MA), providing separation of the two cell populations by a 0.4-microns pore membrane, resulted in a dose-dependent increase in fold expansion of ANK (expansion = 19.9 +/- 4.0-fold; P < .001; n = 22) significantly greater than that observed when NK were cultured alone. Further experiments using the Transwell system showed that the stimulatory effect of autologous PBMNC on ANK progenitor proliferation resides in the CD14+ monocyte fraction (maximal expansion = 14.5 +/- 1.5-fold; n = 17) and not in the CD5+ T-lymphocyte or CD19+ B-lymphocyte fractions. Direct coculture of purified NK and autologous monocytes in the same compartment, thus permitting cell-cell contact, resulted in significantly greater expansion of the ANK population (30.6 +/- 4.7-fold expansion, P < .001; n = 10) than that observed when NK and monocytes were separated by the Transwell membrane. Finally, depletion of PBMNC of cells bearing CD5 and CD8 by panning on antibody-coated plastic flasks resulted in a starting cell population enriched for NK progenitors and for monocytes. Cultures of this resultant population for 18 days in the presence of rIL-2 yielded an ANK population similar to that obtained when CD56+/CD3- cells obtained by FACS were cocultured with autologous monocytes. These results suggest that proliferation of ANK requires autologous monocytes and is in part mediated by humoral factors, but is enhanced when NK and monocytes are in direct cell-cell contact. Depletion of cells bearing CD5 and CD8 from PBMNC is a single efficient method for obtaining a starting population capable of producing large numbers of ANK in culture that may lead to new therapeutic uses for the ANK population.

Adult↗
PubMed1992

The organization engine: virtual data integration.

The Organization Engine is an early example of Virtual Data Integration--providing the appearance of integration at the desktop without modifying existing infrastructure. Starting with the Organization Engine, eight programming days were needed to provide uniform desktop access to a CODASYL-compliant hospital information system and to a MUMPS-based radiology information system (the technique is equally effective for relational and other data bases). The resulting tool provides a seamless integration of these two systems, image storage, pre-recorded audio, and document storage. In addition to providing uniform access, the tool allows healthcare providers to organize the data to suit their individual needs. The ease of this integration lies in two simple techniques: the transformation of data from all sources into a single, homogeneous representation, and the use of simple customization files to describe new object types and formats. The approach is sufficiently general to allow the integration of applications which present external interfaces of radically different forms. Two such forms are discussed here: data map publication and transactions.

Computer Communication Networks↗
PubMed1992

Vascular complications following intra-aortic balloon pump insertion.

The intra-aortic balloon pump (IABP) has been used for 23 years to treat cardiogenic shock from various causes. A retrospective review was conducted to evaluate the morbidity, mortality, and risk factors associated with insertion of this device. Over a recent 3-year period, 415 such pumps were inserted either by percutaneous (323) or cut-down (92) technique in 404 patients. Indications for placement included intraoperative pump failure (46%), cardiac instability before coronary artery bypass grafting (28%), perioperative support (13%), cardiac transplantation (7%), and cardiogenic shock (6%). Noncardiac vascular complications occurred in 67 patients, 55 per cent of whom required surgical correction. Operative procedures included femoral artery thrombectomy, bypass grafting, fasciotomy, and amputation. Major risk factors for vascular complications included diminished or absent femoral pulses on initial examination, being a woman, and obesity. In patients with known peripheral vascular disease, the risk of a vascular complication was 17.9 per cent when a surgical cut-down technique was used to insert the IABP, and 38.9 per cent when a percutaneous insertion was performed. The mortality doubled in those patients who had a vascular complication as compared to those who did not (34% vs 17%). A more liberal use of an open surgical technique in those patients with peripheral vascular disease, obesity, and who are women may help to reduce complications after the insertion of the intra-aortic balloon pump.

Adolescent↗
PubMed1991

Adherent lymphokine-activated killer cells suppress autologous human normal bone marrow progenitors.

We have generated a homogeneous population of recombinant interleukin-2 (rIL-2)-stimulated effector cells termed adherent lymphokine-activated killer cells (A-LAK) from peripheral blood mononuclear cells (PBMNC) of 14 normal individuals and tested the effect of A-LAK cells on autologous hematopoietic bone marrow (BM) progenitor growth. Enrichment of A-LAK from PBMNC depended on the propensity of A-LAK precursors to adhere to plastic and proliferate in the presence of rIL-2. The resultant population had the morphologic appearance of large granular lymphocytes, and the majority of cells (73% +/- 4%) expressed the CD56+/CD3- phenotype associated with rIL-2-stimulated natural killer (NK) cells. The A-LAK population had potent lytic activity in chromium release assays against both NK-sensitive (K562) and NK-resistant (Raji) targets. When BM mononuclear cells (BMMNC) were coincubated with autologous A-LAK and rIL-2 (1,000 U/mL) added at the start of culture, dose-dependent suppression of burst-forming unit-erythroid (BFU-E) and colony-forming unit mix (CFU-MIX) colony growth was observed at effector to target ratios (E:T) ranging from 0.25:1 to 5:1 (maximal suppression BFU-E = 85% +/- 6%; CFU-MIX = 95% +/- 3%). This suppression was rIL-2 dose-dependent, and no suppression was seen in the absence of rIL-2. Depletion of BM monocytes and T lymphocytes did not alter A-LAK suppression of progenitors coincubated with A-LAK cells. Addition of polyclonal neutralizing antibodies against both interferon-gamma (IFN-gamma) and tumor necrosis facto alpha (TNF-alpha) to the coincubation culture completely abrogated the suppressive effect of A-LAK on BFU-E and CFU-MIX colony growth while each neutralizing antibody used alone had intermediate effects. In contrast to coincubation studies, 36 hours of preincubation of A-LAK cells with autologous BM (E:T 2.2:1) and rIL-2 (1,000 U/mL) followed by plating of preincubated BM cells in hematopoietic progenitor culture produced significant suppression of day 14 BFU-E (47% +/- 5%), but spared the more primitive CFU-MIX (7% +/- 9%), suggesting a divergent effect of A-LAK cells on hematopoietic progenitors at different stages of differentiation. Addition of neutralizing antibodies against IFN-gamma and TNF-alpha in preincubation failed to abrogate the suppressive effect of A-LAK on BFU-E colony growth, suggesting that this suppression occurs by a different mechanism than that seen in coincubation studies. Previous studies have demonstrated that the A-LAK population has cytotoxic and proliferative advantages over other killer cell populations.(ABSTRACT TRUNCATED AT 400 WORDS)

Antibodies, Monoclonal↗
PubMed1991

Differential effectiveness of various prior-cuing treatments in the reactivation and maintenance of memory.

In 3 experiments, changes were examined in the characteristics of newly acquired and reinstated memories over time in preweanling rats. Experiment 1 indicated that forgetting after conditioning was monotonic, with the upper limit of retention at approximately 120 min posttraining. In Experiment 2, Ss were exposed to various elements of the training episode before testing, after either a 3- or a 24-hr retention interval. The results indicated that the prior-cuing treatments were differentially effective and that the effectiveness of a reactivation treatment may change as a function of the retention interval. Experiment 3 indicated that Ss expressed a conditioned aversion at much longer intervals following reactivation treatments than after initial conditioning. Furthermore the susceptibility of the reinstated memory to forgetting was dependent on the prior-cuing treatment used. The results suggest a change in the memorial representation of the conditioning episode over time.

Animals↗
PubMed1991

The location of the 5' end of the potato leafroll luteovirus subgenomic coat protein mRNA.

Northern blot analysis of nucleic acid from potato plant tissues and tobacco protoplasts infected with a Scottish isolate of potato leafroll luteovirus (PLRV) detected the 6 kb genomic RNA and one subgenomic RNA species of about 2.7 kb; RNA extracted from virus particles contained only the genomic species. Blotting with small defined probes suggested that the location of the 5' end of the subgenomic RNA was between 2380 and 2510 nucleotides from the 3' end of the PLRV genome (between 3370 and 3500 nucleotides from the 5' end of PLRV Dutch isolate RNA). When RNA extracted from PLRV-infected or mock-inoculated protoplasts was used as the template for primer extension using primers complementary to the sequence at, or upstream of, the initiation codon of the coat protein gene, a single major infection-specific product was detected. A primer complementary to the sequence between 162 and 179 nucleotides upstream of the coat protein AUG yielded a product of 56 nucleotides. Thus, the subgenomic RNA has a leader sequence of 212 nucleotides, is 2505 nucleotides in length and starts at a position equivalent to 3376 nucleotides from the 5' end of the PLRV-Dutch genome, 11 nucleotides upstream of the termination codon of the putative polymerase gene. The nucleotide sequence immediately downstream of this position closely resembles that of the 5' end of the PLRV genomic RNA.

Base Sequence↗
PubMed1991

Ileal pouch-anal anastomosis. The Emory University experience.

The ileal pouch-anal anastomosis has become a practical alternative to proctocolectomy for the treatment of ulcerative colitis and polyposis coli. To evaluate its success, the Emory University Affiliated Hospital experience from February 1984 to March 1989 was retrospectively reviewed. There were a total of 50 patients identified; 84 per cent had ulcerative colitis, and 16 per cent had polyposis coli (familial polyposis and Gardner's syndrome). The majority of these patients underwent a two-stage operation, but one-third required a three-stage procedure due to difficulty in mucosal proctectomy or toxic megacolon. J-pouch construction was performed in 72 per cent of patients, S-pouch construction in 14 per cent, straight ileo-anal anastomosis in 8 per cent, and lateral isoperistaltic ileo-anal anastomosis in 6 per cent. Of the 50 patients, 36 (72%) have had closure of the temporary ileostomy. Fourteen patients have not had ileostomy closure due to change in diagnosis to Crohn's disease, operative complications, or ileostomy closure pending. The combined operative morbidity per patient for the ileal pouch-anal anastomosis and the closure of the ileostomy was 32 per cent. This included bowel obstruction, 16 per cent; pelvic abscess, 6 per cent; and ileo-anal separation, 4 per cent. Follow-up on patients with ileostomy closure ranged from 6 months to 4 years (mean, 1.3 years). Stool frequency was 5.9 stools per 24 hours at 6 months and improved with time. During the follow-up period, all patients were eventually completely continent of stool during the day, and most became completely continent of stool at night.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenomatous Polyposis Coli↗
PubMed1990

Flow cytometric identification of microorganisms by dual staining with FITC and PI.

The identification of microorganisms by flow cytometry was evaluated by using a double staining technique with propidium iodide and fluorescein isothiocyanate and a two dimensional analysis. A diverse group of 19 different species and strains of microorganisms was tested to determine if they could be differentiated by flow cytometry. The organisms tested displayed characteristic and distinct two dimensional fluorescent patterns which allowed ready grouping and differentiation into subsets of organisms. The slopes and correlation coefficients of the histograms and the ratio of red to green signals expressed these differences quantitatively and allowed organisms to be placed into one of three groups based on these values. In some instances, as with Streptococcus pneumoniae and pyogenes and Staphylococcus aureus and epidermidis, it was possible to distinguish between species of bacteria from the same genus. The use of dual dye labeling and flow cytometry provided a rapid method of identifying selected microorganisms and may be broadly applicable for the detection and identification of many bacteria and fungi.

Bacterial Proteins↗
PubMed1990

Ontogenetic differences in the expression of odor-aversion learning in 4- and 8-day-old rats.

Two experiments investigated the ability of preweanling rats, 4 or 8 days of age, to form an odor-LiCl association across various CS-US delays. The results of the odor preference test indicated that 8-day-old subjects acquired an aversion to the CS+ odor when trained with either a 0 or 15 min CS-US delay, while 4-day-old subjects did not exhibit a reduction in preference for the CS+ at any of the CS-US delays tested. The absence of a reduction in preference for the CS+ by 4-day-old rats could not be attributed to their failure to acquire the odor aversion, however; they avoided a texture with which the CS+ odor was paired in a second order conditioning paradigm. The results suggest that outcomes appearing to represent age-related differences in associative learning may in some instances be more appropriately viewed as representing ontogenetic differences in the way in which acquired associations are manifested in behavior.

Age Factors↗
PubMed1990

Conditioning of morphine-induced taste aversion and analgesia.

The process of selective associations is evident in the aversive conditioning literature, where it has been shown that external cues are readily associated with peripheral pain, whereas taste cues are more easily associated with effects of drug administration. Within this framework, it is of interest that the failures to obtain a conditioned analgesic response to a morphine-associated CS have used external cues as conditioned stimuli. In Experiment 1, subjects re-exposed to a morphine-associated CS not only expressed the anticipated taste aversion, but also exhibited a decrease in pain sensitivity that was evident 15 or 30 min following CS re-exposure. Experiment 2 suggested that the conditioned analgesic response was opioid mediated, as pre-test administration of naloxone blocked expression of the analgesic CR. In Experiment 3, an increase in opiate receptor sensitivity produced by chronic naltrexone treatment did not affect the strength of the taste aversion, but resulted in an increase in the magnitude of the conditioned analgesic response. Collectively, these data suggest a neuropharmacological dissociation in systems mediating the two responses.

Analgesia↗
PubMed1990

Comparison of vancomycin- and teicoplanin-induced histamine release and "red man syndrome".

Twelve healthy adult males participated in a double-blind, randomized, two-way crossover study to determine histamine release and the frequency and severity of "red man syndrome" (RMS) following intravenous administration of vancomycin (15 mg/kg of body weight over 60 min) and teicoplanin (15 mg/kg over 30 min). Concentrations of vancomycin and teicoplanin in serum and concentrations of histamine in plasma were measured at baseline and during and after each infusion. Erythema and pruritus were classified a priori as mild, moderate, or severe. The extent of erythema was determined by the use of a burn chart, and pruritus was assessed by the subject with a rank scale. Global severity of RMS was determined by summation of the individual scores for pruritus and erythema. Baseline areas under the concentration-time curve for histamine were not significantly different for the vancomycin and teicoplanin treatments. Vancomycin caused RMS in 11 of 12 subjects (9 severe and 2 moderate cases) and was associated with a significant increase in plasma histamine (46.7 +/- 31.3 ng.min/ml, P less than 0.05). In contrast, teicoplanin did not cause RMS or elicit significant histamine release (8.7 +/- 13.2 ng.min/ml). Peak concentrations of vancomycin and teicoplanin in serum were 58.8 +/- 8.4 and 148.0 +/- 31.8 micrograms/ml, respectively (P less than 0.05). Assuming equal efficacy, these data suggest that teicoplanin may be a safe alternative agent in subjects experiencing severe RMS due to vancomycin; however, further studies in the clinical setting are needed.

Adult↗
PubMed1990

Cloning and characterization of a second complementary DNA for human tryptase.

A second cDNA for human tryptase, called beta-tryptase, was cloned from a mast cell cDNA library in lambda ZAP. Its nucleotide sequence and corresponding amino acid sequence were determined and compared with those of a previously cloned tryptase cDNA, now called alpha-tryptase. The 1,142-base sequence of beta-tryptase encodes a 30-amino acid leader sequence of 3,089 D and a 245-amino acid catalytic region of 27,458 D. The amino acid sequence of beta-tryptase is 90% identical with that of alpha-tryptase, the first 20 amino acids of the catalytic portions being 100% identical. This identity, together with recognition of each recombinant protein by monoclonal antibodies directed against purified tryptase validate the tryptase identity of both alpha-tryptase and beta-tryptase cDNA molecules. Modest differences between the nucleic acid sequences of alpha- and beta-tryptase occurred throughout the cDNA molecules except in the 3' noncoding regions, which were identical. Although most highly conserved regions of amino acid sequence in the trypsin superfamily are conserved in both tryptase molecules, beta-tryptase has one carbohydrate binding site compared to two in alpha-tryptase, and one additional amino acid in the catalytic sequence. Regions of the substrate binding pocket in beta-tryptase (DSCQ, residues 218-221; SWG, residues 243-245) differ slightly from those in alpha-tryptase (DSCK, residues 217-220; SWD, residues 242-244). The presence of both alpha- and beta-tryptase sequences in each haploid genome was indicated by finding alpha- and beta-tryptase specific fragments after amplification by PCR of genomic DNA in 10 unrelated individuals. Localization of both alpha- and beta-tryptase sequences to human chromosome 16 was then performed by analysis of DNA preparations from 25 human/hamster somatic hybrids by PCR. It is now possible to assess the expression of each tryptase cDNA by mast cells and the relationship of each gene product to the active enzyme.

Amino Acid Sequence↗
PubMed1990

Current management of choledocholithiasis.

Choledocholithiasis may be managed by surgical extraction of stones or endoscopic papillotomy with extraction of stones. To evaluate these methods of management, the charts of all patients with choledocholithiasis admitted to Crawford Long Hospital of Emory University between April 1, 1983, and April 30, 1988, were reviewed. One hundred patients were identified; 42 were treated by common bile duct exploration (CBDE) and 58 had endoscopic papillotomy with extraction of stones (EP) as their initial treatment. The two groups were similar in regards to age, but the CBDE group had more comorbid conditions (average 2.5/patient in CBDE vs 1.8/patient in EP) and a higher incidence of acute cholecystitis and/or cholangitis (74% of CBDE patients; 24% of EP patients). Successful extraction of all stones occurred in 79 per cent of CBDE patients and 90 per cent of EP patients. Of those patients with retained stones following CBDE, all were later extracted by EP. Of patients having EP as their initial procedure, 24 per cent required repeat endoscopic procedures for extraction of residual stones and only six patients (10.4%) required CBDE for retained stones. Morbidity was lower (10% vs 23%) and hospital stay shorter (3.6 days vs 10.4 days) in the EP than CBDE patients; thus, the two groups are not completely comparable. Mortality was similar in the two groups (1.7% EP, 2.3% CBDE).

Adolescent↗
PubMed1989

Pathophysiology of transitional tumor cell adherence to sites of urothelial injury in rats: mechanisms mediating intravesical recurrence due to implantation.

The mechanism by which transitional tumor cells adhere to areas of urothelial injury and the means by which heparin prevents this phenomenon were studied. Scanning electron microscopy and a radiolabeled tumor cell adherence assay were used to assess the activity of heparin and a "nonglycosaminoglycan" thrombolytic agent, recombinant tissue plasminogen activator, in preventing tumor cell adherence to areas of urothelial injury. Systemically administered heparin and intravesical therapy with recombinant tissue plasminogen activator duplicated the activity of intravesical heparin. Scanning electron microscopy showed tumor cells entrapped at the injury surface in a RBC/fibrin clot, which was prevented by intravesical heparin. These data suggest that clotting cascade activation by urothelial injury is the mechanism by which particulate adherence to the urothelium occurs. Interruption of this process by local or systemic anticoagulation with heparin or shifting of the equilibrium of clot formation/lysis toward thrombolysis with recombinant tissue plasminogen activator prevents tumor cell adherence. Intravesical thrombolytic therapy may represent a new approach to recurrence prophylaxis for superficial bladder carcinoma.

Animals↗