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Biomedical subjects

M Ingram

Publications and source records attributed to M Ingram.

At least 55 records · Page 3Linked to original sources
PubMed1990

Immunohistochemical detection and correlation between MHC antigen and cell-mediated immune system in recurrent glioma by APAAP method.

As part of an on-going clinical trial of immunotherapy for recurrent malignant gliomas, using alkaline phosphatase-anti-alkaline phosphatase method with monoclonal antibodies, we investigated the correlation between expression of the major histocompatibility complex (MHC) and the subpopulation of tumor-infiltrating lymphocytes (TILs) in 38 glioma specimens (20 grade IV, 11 grade III, and 7 grade II) from 33 patients. Thirty specimens (78.9%) were positive to class I MHC antigen and 20 (52.6%) were positive to class II MHC antigen. The correlations between class I MHC antigen expression and the number of infiltrating T8 (p less than 0.01), and also between class II MHC antigen expression and the number of infiltrating T4 (p less than 0.05) were significant. We conclude that TILs are the result of immunoreaction (host-defense mechanism). 31.6% of specimens had perivascular infiltration of T cells. The main infiltrating lymphocyte subset in moderate to marked perivascular cuffing was T4. Our results may indicate that lack of MHC antigen on the glioma cell surface has a share in the poor immunogenicity in glioma-bearing patients. In addition, considering the effector/target ratio, the number of infiltrating lymphocytes against glioma cells was too small, so the immunological intervention seems to be essential in glioma therapy. Previous radiation therapy and chemotherapy, including steroid therapy, did not influence lymphocyte and macrophage infiltration.

Adult↗
PubMed1990

Ultrasonic study of amnioinfusion. A report of two cases.

Two patients had amnioinfusion with subsequent improvement in fetal heart rate (FHR) patterns. Ultrasound in case 1 showed a pocket of saline around the umbilical cord and improved FHR. Case 2 likewise had an improvement in the FHR without ultrasonic evidence of a protective pocket of fluid. Case 2 actually had a tight true knot in the cord, which explained the abnormal FHR pattern. Amnioinfusion can form a protective pocket of fluid around the umbilical cord in cases of severe oligohydramnios, although in our experience its success rate is low and unpredictable.

Adolescent↗
PubMed1990

Lymphocyte metabolism and cytotoxic activity monitored with 31P magnetic resonance spectroscopy.

Continuous metabolic monitoring of human lymphocytes and a tumor cell line was achieved by means of nuclear magnetic resonance (NMR) applied to cells suspended in alginate gels. Human peripheral blood lymphocytes cultured in vitro were examined with 31P magnetic resonance spectroscopy (MRS) before and after activation with phytohemagglutinin and interleukin-2 (IL-2). Following the addition of these biological response modifiers, increases in [ATP], phosphomonoesters (PME), and phosphodiesters occurred. These appear to be markers of lymphocyte stimulation. Lymphocyte pH was unchanged. A target tumor cell line (K562) showed 31P NMR spectra that differed significantly from that of lymphocytes. When lymphocytes were mixed with tumor cells (to induce tumor cell death), and monitored by 31P MRS, levels of inorganic phosphate (Pi) increased, [PME] levels fell, and release of H+ was inhibited. 31P MRS may therefore provide a noninvasive assay of lymphocyte-mediated tumor cell killing that will have application in monitoring treatment in patients undergoing this type of therapy.

Adenosine Triphosphate↗
PubMed1987

Salvage immunotherapy of malignant glioma.

We present the preliminary results of a phase I trial of adoptive immunotherapy for recurrent or residual malignant glioma. The protocol is based on surgical debulking followed by implantation into the tumor bed of autologous lymphocytes that have been stimulated with phytohemagglutinin-P and then cultured in vitro in the presence of interleukin 2. Fifty-five patients with a mean Karnofsky rating of 64 were treated between February 1985 and March 1987. No significant toxicity was associated with the immunotherapy. Fifty patients had a positive initial response to therapy, nine patients had early recurrence (two to four months after treatment), and 22 patients died. We comment on major differences between the protocol described and other immunotherapy protocols.

Adult↗
PubMed1987

Preliminary clinical trial of immunotherapy for malignant glioma.

An immunotherapy protocol based on intracranial implantation of stimulated, autologous lymphocytes into the tumor bed following surgical debulking of malignant glioma is described. Phase I clinical trials in human patients are now in progress. Preliminary data representing the first 39 patients treated are presented briefly.

Adult↗
PubMed1986

Plasma atrial natriuretic peptide: responses to modest and severe sodium restriction.

Plasma atrial natriuretic peptide (ANP), active renin and aldosterone concentrations were measured during modest and severe sodium restriction in 16 normal volunteers. Eight volunteers took, in two separate 4-day periods, diets containing 200 and 15 mmol sodium/day (plus frusemide, 40 mg, on day 1 of low sodium intake), in random order. With sodium restriction plasma ANP concentrations fell in parallel with cumulative sodium balance. Changes in plasma renin and aldosterone were reciprocal to those in plasma ANP. To assess the threshold and reproducibility of the effects of modest sodium restriction on plasma ANP concentrations, a further group of eight volunteers took identical constant sodium diets (80 mmol/day in two cases and 120 mmol/day in the remainder) for 4 days on two successive weeks. On both occasions similar individual and mean falls in plasma ANP values accompanied the small net sodium loss occurring on these regimes. Plasma active renin concentration rose significantly during both diet phases. These data suggest plasma ANP concentrations alter in response to minor changes in sodium status, and are consistent with a role for plasma ANP in physiological regulation of body fluid volumes.

Adult↗
PubMed1985

Effect of changes in dietary sodium and potassium on blood pressure and cellular electrolyte handling in young normotensive subjects.

In a study on 22 normotensive male subjects, a change in dietary sodium intake from 29.6 +/- 6.0 to 332.5 +/- 13.9 mmol/day (mean +/- s.e.m.), over 7 days, was associated with a significant rise in supine and standing systolic blood pressure and a fall in sodium pump activity. Intracellular sodium remained constant, while intracellular potassium fell. These changes appeared to be reversed by the addition of potassium (96 mmol/day) to the high sodium diet. The 12 subjects with a family history of essential hypertension, as determined by measurement of parental blood pressure, did not differ in their response from those whose parents were normotensive.

Adult↗
PubMed1984

Purification of beta cells from rat islets by monoclonal antibody-fluorescence flow cytometry.

Fluoresceinated monoclonal antibody plus flow cytometry was used to purify beta cells from mixed pancreatic islet endocrine cell populations. A2B5, a monoclonal antibody to a glycolipid on the surface of cells of neuroendocrine origin, was incubated with single cells dissociated from rat pancreatic islets. Antibody-bound cells were labeled with fluoresceinated goat F(ab')2 antimouse immunoglobulin and highly fluorescent cells were separated from less fluorescent cells on a Coulter EPICS IV cell sorter. Sorted cell populations were analyzed by radioimmunoassay for insulin, glucagon, and somatostatin. The highly fluorescent cell population was enriched sixfold for insulin-containing beta cells, indicating that islet beta cells are relatively enriched in A2B5 antigen and can be partially purified by this method.

Animals↗
PubMed1983

Mitosis of contact-inhibited 3T3 preadipocytes precedes chemically induced differentiation into adipocytes.

We studied the conversion of 3T3 cells into adipocytes in vitro after pulsed exposure of confluent, nongrowing cultures to various combinations of the "triggering" agents, methylisobutylxanthine, dexamethasone, and fetal calf serum. Conversion of nongrowing 3T3 preadipocytes into adipocytes takes place after the cells have been stimulated to undergo one round of cell division. Maximal cell division and cytodifferentiation occur only when all three triggering agents are present.

1-Methyl-3-isobutylxanthine↗
PubMed1982

The effect of some beta-lactam antibiotics on Escherichia coli studied by flow cytometry.

The effects of three beta-lactam antibiotics on Escherichia coli were studied by means of flow cytometry. Since these agents block bacterial cell wall synthesis in such manner as to prevent septal formation without appreciably affecting nucleic acid synthesis, the resulting cell elongation caused by these agents can be assessed by nucleic acid fluorescent staining. It was shown by this technique that the somatic effects of cefazolin, cefamandole and moxalactam were related both to the antibiotic concentration and time of exposure to the drugs and were observable within 30 minutes of the initial exposure of the cultures to these agents. These results demonstrate that fluorescent cytometry can provide accurate assessment of the effects of compounds that inhibit cell wall formation. This technology could be a useful tool for comparing antibiotic somatic effects on bacteria and for rapidly and reliably determining their sensitivity and resistance to these agents.

Anti-Bacterial Agents↗
PubMed1982

Preparation of rat islet B-cell-enriched fractions by light-scatter flow cytometry.

Flow cytometry has been examined as a method to separate islet cells into homogeneous subpopulations. Collagenase-isolated rat islets were dissociated into single cells and these were analyzed and sorted according to their low forward angle light scattering properties by using automated flow cytometry. Light scatter histograms showed two peaks of viable cells. Radioimmunoassay of hormone content in cell fractions collected across the the two peaks showed that glucagon-containing cells were concentrated towards the left side of the left peak and somatostatin-containing cells were concentrated towards the right side of the left peak, whereas insulin-containing cells were clearly enriched in the right peak. The B-cell-enriched fraction (90% B cells, 3% A cells, 2% D cells) exhibited significant insulin secretory responses to glucose (16.7 mM), and 3-isobutyl-1-methylxanthine (0.1 mM), during a 24-h culture period, and these responses were slightly greater than those observed in the original mixed islet cell preparation (66% B cells, 14% A cells, and 4% D cells). These results indicate that flow cytometry can be applied to sort pancreatic islet cells into populations enriched in specific endocrine cell types for further study of the functions of individual cell types.

Animals↗
PubMed1982

Purification of human granulocyte-macrophage progenitor cells (CFU-C) using indirect immunofluorescence and cell sorting.

We have attempted to purify human bone marrow granulocyte-macrophage progenitor cells utilizing purified stimulating factor, indirect immunofluorescence and cell sorting. These cells can be labelled by sequential incubation with colony-stimulating factor (CSF), rabbit anti-CSF antibody and fluorescently labelled goat anti-rabbit gamma globulin. Flow photometry demonstrated that binding of CSF to marrow cells varied with CSF concentration and duration of incubation. Marrow cells were pre-concentrated by incubation with carbonyl iron followed by Percoll gradient centrifugation and then labelled by this indirect immunofluorescence method. Sorting of these cells yielded up to 95-fold purification of colony-forming cells and fractions containing in excess of 10% colony- and cluster-forming cells.

Bone Marrow Cells↗
PubMed1981

Establishment and cell cycle kinetics of a human squamous cell carcinoma in nude mice and in vitro.

A human squamous cell carcinoma of the virus was xenografted to athymic, nude mice. A tissue culture cell line designated SqCaVu-1H was derived from a second-passage xenograft. The growth characteristics and cell cycle kinetics in the xenografts and in SqCaVu-1H cells were compared. Approximately 80% of the tumor implants produced growing xenografts which had a 2-week latent period followed by Gompertzian growth with a doubling time of 5 to 30 days at 35 days postimplantation. The cell cycle kinetics of the xenografts revealed a heterogeneity from region to region within the tumor. G2 phase and S phase in the xenografts are approximately 8 and 13 hr, respectively. The SqCaVu-1H cells contain only human chromosomes. The modal chromosome number was 64. SqCaVu-1H cells produce plasminogen activator during logarithmic growth, and they produce tumors when injected s.c. into athymic, nude mice. Logarithmically growing SqCaVu-1H cells have a population-doubling time of 21.8 hr in tissue culture. In vitro, their cell cycle duration is approximately 16.0 hr, with G2 phase at 5.6 hr and S phase at 8.6 hr. Comparison of the growth of the same human tumor cells under in vivo and in vitro conditions serves to emphasize that tumor cell proliferation depends strongly on the microenvironment. The varied proliferation characteristics are correlated with their varied inhibition of deoxyuridine incorporation into DNA because of exposure to methotrexate. Logarithmically growing SqVaCu-1H cells had a 50% inhibitory dose of 2.2 X 10(-6) M. Plateau-phase cells in vitro had a 50% inhibitory dose of 9 X 10(-6) M, while the inhibition of cells from the xenografts was nearly dose independent.

Animals↗
PubMed1980

Collodion membrane secures cells sorted by flow cytofluorometry onto microscope slides.

Quantitative microscopic cytology of cells previously sorted by flow cytofluorometry has been hindered by the loss of cells from the microscope slide during staining procedures. The simple application of a semi-permeable membrane of collodion over fixed or unfixed cells sorted directly onto a microscope slide secured virtually 100% of the cells onto the slide. Cells covered with the collodion membrane studied with Papanicolaou's stain as well as routine clinical cervical cytologic preparations. In contrast, fewer than one half of the cells sorted onto uncoated or albumin coated slides were retained after staining.

Carcinoma, Squamous Cell↗