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1.
BMC Pulm Med ; 21(1): 275, 2021 Aug 23.
Article in English | MEDLINE | ID: mdl-34425811

ABSTRACT

BACKGROUND: How cigarette smoke (CS) and chronic obstructive pulmonary disease (COPD) affect severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection and severity is controversial. We investigated the effects of COPD and CS on the expression of SARS-CoV-2 entry receptor ACE2 in vivo in COPD patients and controls and in CS-exposed mice, and the effects of CS on SARS-CoV-2 infection in human bronchial epithelial cells in vitro. METHODS: We quantified: (1) pulmonary ACE2 protein levels by immunostaining and ELISA, and both ACE2 and/or TMPRSS2 mRNA levels by RT-qPCR in two independent human cohorts; and (2) pulmonary ACE2 protein levels by immunostaining and ELISA in C57BL/6 WT mice exposed to air or CS for up to 6 months. The effects of CS exposure on SARS-CoV-2 infection were evaluated after in vitro infection of Calu-3 cells and differentiated human bronchial epithelial cells (HBECs), respectively. RESULTS: ACE2 protein and mRNA levels were decreased in peripheral airways from COPD patients versus controls but similar in central airways. Mice exposed to CS had decreased ACE2 protein levels in their bronchial and alveolar epithelia versus air-exposed mice. CS treatment decreased viral replication in Calu-3 cells, as determined by immunofluorescence staining for replicative double-stranded RNA (dsRNA) and western blot for viral N protein. Acute CS exposure decreased in vitro SARS-CoV-2 replication in HBECs, as determined by plaque assay and RT-qPCR. CONCLUSIONS: ACE2 levels were decreased in both bronchial and alveolar epithelial cells from COPD patients versus controls, and from CS-exposed versus air-exposed mice. CS-pre-exposure potently inhibited SARS-CoV-2 replication in vitro. These findings urge to investigate further the controversial effects of CS and COPD on SARS-CoV-2 infection.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , COVID-19/enzymology , Cigarette Smoking/metabolism , Pulmonary Disease, Chronic Obstructive/enzymology , SARS-CoV-2/physiology , Smoke , Aged , Aged, 80 and over , Angiotensin-Converting Enzyme 2/genetics , Animals , Bronchi , Cell Line, Tumor , Female , Humans , Male , Mice , Middle Aged , Patient Acuity , Pulmonary Alveoli , RNA, Messenger/metabolism , Respiratory Mucosa/metabolism , Serine Endopeptidases/genetics , Nicotiana , Virus Replication
2.
J Acoust Soc Am ; 132(1): 239-48, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22779473

ABSTRACT

Activated carbon can adsorb and desorb gas molecules onto and off its surface. Research has examined whether this sorption affects low frequency sound waves, with pressures typical of audible sound, interacting with granular activated carbon. Impedance tube measurements were undertaken examining the resonant frequencies of Helmholtz resonators with different backing materials. It was found that the addition of activated carbon increased the compliance of the backing volume. The effect was observed up to the highest frequency measured (500 Hz), but was most significant at lower frequencies (at higher frequencies another phenomenon can explain the behavior). An apparatus was constructed to measure the effective porosity of the activated carbon as well as the number of moles adsorbed at sound pressures between 104 and 118 dB and low frequencies between 20 and 55 Hz. Whilst the results were consistent with adsorption affecting sound propagation, other phenomena cannot be ruled out. Measurements of sorption isotherms showed that additional energy losses can be caused by water vapor condensing onto and then evaporating from the surface of the material. However, the excess absorption measured for low frequency sound waves is primarily caused by decreases in surface reactance rather than changes in surface resistance.

3.
Proc Math Phys Eng Sci ; 476(2237): 20190838, 2020 May.
Article in English | MEDLINE | ID: mdl-32523412

ABSTRACT

Vegetation on railway or highway slopes can improve slope stability through the generation of soil pore water suctions by plant transpiration and mechanical soil reinforcement by the roots. To incorporate the enhanced shearing resistance and stiffness of root-reinforced soils in stability calculations, it is necessary to understand and quantify its effectiveness. This requires integrated and sophisticated experimental and multi-scale modelling approaches to develop an understanding of the processes at different length scales, from individual root-soil interaction through to full soil-profile or slope scale. One of the challenges with multi-scale models is ensuring that they sufficiently closely represent real behaviour. This requires calibration against detailed high-quality and data-rich experiments. This study presents a novel experimental methodology, which combines in situ direct shear loading of a willow root-reinforced soil with X-ray computed tomography to capture the three-dimensional chronology of soil and root deformation within the shear zone. Digital volume correlation (DVC) analysis was applied to the computed tomography dataset to obtain full-field three-dimensional displacement and strain information. This paper demonstrates the feasibility and discusses the challenges associated with DVC experiments on root-reinforced soils.

4.
bioRxiv ; 2020 Dec 07.
Article in English | MEDLINE | ID: mdl-33330864

ABSTRACT

INTRODUCTION: How cigarette smoke (CS) and chronic obstructive pulmonary disease (COPD) affect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and severity is controversial. We investigated the protein and mRNA expression of SARS-CoV-2 entry receptor ACE2 and proteinase TMPRSS2 in lungs from COPD patients and controls, and lung tissue from mice exposed acutely and chronically to CS. Also, we investigated the effects of CS exposure on SARS-CoV-2 infection in human bronchial epithelial cells. METHODS: In Cohort 1, ACE2-positive cells were quantified by immunostaining in FFPE sections from both central and peripheral airways. In Cohort 2, we quantified pulmonary ACE2 protein levels by immunostaining and ELISA, and both ACE2 and TMPRSS2 mRNA levels by RT-qPCR. In C57BL/6 WT mice exposed to air or CS for up to 6 months, pulmonary ACE2 protein levels were quantified by triple immunofluorescence staining and ELISA. The effects of CS exposure on SARS-CoV-2 infection were evaluated after 72hr in vitro infection of Calu-3 cells. After SARS-CoV-2 infection, the cells were fixed for IF staining with dsRNA-specific J2 monoclonal Ab, and cell lysates were harvested for WB of viral nucleocapsid (N) protein. Supernatants (SN) and cytoplasmic lysates were obtained to measure ACE2 levels by ELISA. RESULTS: In both human cohorts, ACE2 protein and mRNA levels were decreased in peripheral airways from COPD patients versus both smoker and NS controls, but similar in central airways. TMPRSS2 levels were similar across groups. Mice exposed to CS had decreased ACE2 protein levels in their bronchial and alveolar epithelia versus air-exposed mice exposed to 3 and 6 months of CS. In Calu3 cells in vitro, CS-treatment abrogated infection to levels below the limit of detection. Similar results were seen with WB for viral N protein, showing peak viral protein synthesis at 72hr. CONCLUSIONS: ACE2 levels were decreased in both bronchial and alveolar epithelial cells from uninfected COPD patients versus controls, and from CS-exposed versus air-exposed mice. CS-pre-treatment did not affect ACE2 levels but potently inhibited SARS-CoV-2 replication in this in vitro model. These findings urge to further investigate the controversial effects of CS and COPD on SARS-CoV2 infection.

5.
Gene Ther ; 16(1): 127-35, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18784748

ABSTRACT

The development of clinically beneficial myocardial gene therapy has been slowed by reliance on the use of viral carriers and non-physiologic, constitutive gene expression. To specifically address these issues, we have developed a non-viral gene carrier, water-soluble lipopolymer (WSLP), and an ischemia-inducible plasmid construct expressing vascular endothelial growth factor (VEGF), pRTP801-VEGF, to treat myocardial ischemia and infarction. Rabbits underwent ligation of the circumflex artery followed by injection of (a) an ischemia-inducible VEGF gene construct in a WSLP carrier; (b) a constitutively expressed, or unregulated, SV-VEGF gene construct in a WSLP carrier; (c) WSLP carrier alone; or (d) no injection therapy. Following 4 weeks treatment, ligation alone resulted in infarction of 48+/-7% of the left ventricle. With injection of WSLP carrier alone, 49+/-6% of the left ventricle was infarcted (P=NS). The constitutively expressed gene construct, SV-VEGF, reduced the infarct size to 32+/-7% of the left ventricle (P=0.007). The ischemia-inducible gene construct, RTP801-VEGF, further reduced the infarct size to 13+/-4% of the left ventricle (P<0.001). The use of a non-viral carrier to deliver an ischemia-inducible VEGF construct is effective in the treatment of acutely ischemic myocardium.


Subject(s)
Genetic Therapy/methods , Myocardial Infarction/therapy , Myocardium/metabolism , Transfection/methods , Vascular Endothelial Growth Factor A/genetics , Animals , Apoptosis , Cell Line , Gene Expression , Injections , Models, Animal , Myocardial Infarction/metabolism , Myocardial Infarction/pathology , Myocardium/pathology , Polymers , Rabbits , Vascular Endothelial Growth Factor A/analysis
6.
Br J Cancer ; 100(3): 538-44, 2009 Feb 10.
Article in English | MEDLINE | ID: mdl-19190634

ABSTRACT

Little is known about how reproductive factors affect the risk of breast cancers of different histology. In an analysis of prospective data on 1.2 million middle-aged UK women, we used proportional hazards models to estimate the relative risks of six histological types in relation to menarche, childbearing and menopause. During 8.7 million person-years of follow-up, 17 923 ductal, 3332 lobular, 1062 tubular, 944 mixed ductal lobular, 330 mucinous and 117 medullary cancers were diagnosed. The effect of both age at menarche and age at first birth was greatest for lobular tumours; relative risks per 5-year increase in age at menarche for ductal, lobular, and tubular cancers were 0.93 (0.87-0.99), 0.65 (0.56-0.76), and 0.75 (0.57-0.98), respectively (P-value for heterogeneity=0.0001); and the relative risks per 5-year increase in age at first birth were 1.10 (1.07-1.12), 1.23 (1.17-1.29), and 1.13 (1.03-1.23), respectively (P-value for heterogeneity=0.0006). Increasing parity reduced the risk of each tumour type, except medullary cancers, but the reduction in risk was greater for mucinous cancers than for any other subtype considered (P<0.05 for comparison with each other subtype in turn). The effect of menopause did not vary significantly by tumour histology. Meta-analysis of published results on the effects of age at menarche and age at first birth on ductal and lobular cancers were in keeping with our findings.


Subject(s)
Breast Neoplasms/pathology , Breast Neoplasms/physiopathology , Reproduction , Female , Humans , Middle Aged , Prospective Studies
7.
Science ; 207(4434): 1003-4, 1980 Feb 29.
Article in English | MEDLINE | ID: mdl-7352294

ABSTRACT

Auditory thresholds were determined for infants and adults to half-octave bands of noise centered at 10,000 and 19,000 hertz. Adults were significantly more sensitive than infants at 10,000 hertz, but at 19,000 hertz, adults and infants had comparable thresholds.


Subject(s)
Auditory Threshold/physiology , Hearing/physiology , Pitch Perception/physiology , Adult , Age Factors , Child, Preschool , Environment , Humans , Infant , Noise
8.
Science ; 181(4103): 957-9, 1973 Sep 07.
Article in English | MEDLINE | ID: mdl-4730450

ABSTRACT

A purified preparation of mixed human peripheral blood lymphocytes and monocytes was used in an inhibition-of-migration assay for cell-mediated immunity to cancer of the colon. This preparation was reproducibly antigen-responsive and migrated with greater reliability than did a more complex cell mixture. Of 27 patients with this disease, cells from 24 showed inhibited migratio in response to colon carcinoma antigen. Uninhibited migration patterns were found in each of the 52 cancer-free controls, including eight patients with nonmalignant disease initially diagnosed as cancer of the colon, and in nine patients with surgically cured adenocarcinoma of the colon.


Subject(s)
Adenocarcinoma/immunology , Antigens, Neoplasm , Cell Migration Inhibition , Colonic Neoplasms/immunology , Age Factors , Aged , Colonic Neoplasms/diagnosis , Female , Humans , Lymphocytes/immunology , Male , Middle Aged , Monocytes/immunology , Prognosis
9.
Science ; 221(4608): 374-6, 1983 Jul 22.
Article in English | MEDLINE | ID: mdl-17798893

ABSTRACT

Larvae of the black swallowtail butterfly, Papilio polyxenes Stoll, forage successfully on plants that contain high levels of photosensitizing psoralens. These insects rapidly detoxify psoralens, particularly in the midgut tissue prior to absorption, with the result that appreciable levels of unmetabolized phototoxin do not enter the body circulation where deleterious light-induced interactions with dermal or subdermal tissues would occur.

10.
Mar Pollut Bull ; 145: 508-516, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31590818

ABSTRACT

Particle flux material collected in 2000 m depth in the Northeast Atlantic at 33°N and 22°W was analyzed for trace metals and persistent organic pollutants. Element enrichment factors relative to lithogenic Al were elevated indicating possible anthropogenic contributions for all trace metals except V. Polycyclic aromatic hydrocarbons, polychlorinated biphenyls and the pesticide DDT exhibited median fluxes of 10.40 µg m-2d-1,0.29 µg m-2 d-1, and 0.90 µg m-2 d-1, respectively. Flux composition reflected long range transport, with low molecular weight and low-chlorinated compounds dominating ∑15PAH and ∑23PCB. PAH isomer ratios identified fossil fuel combustion as the main ∑15PAH source. The composition of ∑4DDT suggested inputs of the fresh technical pesticide during high dust intensity periods. Pollutant fluxes showed seasonality linked to export production in the region, as well as a dependence on annual and sub-annual dust input events.


Subject(s)
Metals/analysis , Polychlorinated Biphenyls/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Water Pollutants, Chemical/analysis , Atlantic Ocean , Dust , Environmental Monitoring , Pesticides/analysis , Seasons
11.
J Clin Invest ; 59(5): 966-74, 1977 May.
Article in English | MEDLINE | ID: mdl-323291

ABSTRACT

Viable suspensions of human colonic mucosal lymphoid cells have been prepared by sequential treatment of tissue with dithiothreitol, EDTA in calcium- and magnesium-free salt solutions, and purified collagenase. The intestinal lymphocyte population, in comparison with that of peripheral blood, had greater numbers of bone marrow-derived cells, particularly cells bearing membrane IgA; showed spontaneous association with macrophages; underwent rapid rosette formation with sheep erythrocytes; and demonstrated increased in vitro synthesis of immunoglobulin. Total thymus-derived cells were equal in the two populations. Decreases were found in "null" cell numbers, in cells bearing membrane IgD and IgM, and in responsiveness to phytohemagglutinin. Macrophage/monocytes in the intestinal population were increased in size, granularity, motility, sustained glass adherence, and phagocytic activity. Human intestinal lymphoid cells appear to constitute a cell population that is more "mature" and/or "activated", in comparison with the lymphoid cells of peripheral blood. The method of preparation should lend itself to the study of inflammatory bowel disease, gastrointestinal cancer, and the intestinal secretory immune system.


Subject(s)
Immunoglobulins/analysis , Intestinal Mucosa/cytology , Lymphocytes/immunology , Membrane Proteins/analysis , Antibody Formation , Cell Separation/methods , Colon/cytology , Humans , Immunologic Techniques , Lectins , Lymphocyte Activation , Microscopy, Fluorescence
12.
Bioinspir Biomim ; 13(1): 015005, 2017 12 28.
Article in English | MEDLINE | ID: mdl-29185995

ABSTRACT

The accuracy of calculations of both the degree and angle of polarization depend strongly on the noise in the measurements used. The noise in the measurements recorded by both camera based systems and spectrometers can lead to significant artefacts and incorrect conclusions about high degrees of polarization when in fact none exist. Three approaches are taken in this work: firstly, the absolute error introduced as a function of the signal to noise ratio for polarization measurements is quantified in detail. An important finding here is the reason for why several studies incorrectly suggest that black (low reflectivity) objects are highly polarized. The high degree of polarization is only an artefact of the noise in the calculation. Secondly, several simple steps to avoid such errors are suggested. Thirdly, if these points can not be followed, two methods are presented for mitigating the effects of noise: a maximum likelihood estimation method and a new denoising algorithm to best calculate the degree of polarization of natural polarization information.


Subject(s)
Biophysics/methods , Light , Signal-To-Noise Ratio , Visual Perception/physiology , Algorithms , Animals , Artifacts , Biophysics/instrumentation , Coleoptera/physiology , Computer Simulation , Image Processing, Computer-Assisted/methods , Likelihood Functions
13.
J Phys Condens Matter ; 29(15): 155401, 2017 Apr 20.
Article in English | MEDLINE | ID: mdl-28199221

ABSTRACT

We have studied the compressibility and stability of different ß-titanium alloys at high pressure, including binary Ti-Mo, Ti-24Nb-4Zr-8Sn (Ti2448) and Ti-36Nb-2Ta-0.3O (gum metal). We observed stability of the ß phase in these alloys to 40 GPa, well into the ω phase region in the P-T diagram of pure titanium. Gum metal was pressurised above 70 GPa and forms a phase with a crystal structure similar to the η phase of pure Ti. The bulk moduli determined for the different alloys range from 97 ± 3 GPa (Ti2448) to 124 ± 6 GPa (Ti-16.8Mo-0.13O).

14.
Phys Rev E ; 96(5-1): 052113, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29347717

ABSTRACT

We report experimental evidence for a crossover between a liquidlike state and a gaslike state in fluid methane (CH_{4}). This crossover is observed in all of our experiments, up to a temperature of 397 K, 2.1 times the critical temperature of methane. The crossover has been characterized with both Raman spectroscopy and x-ray diffraction in a number of separate experiments, and confirmed to be reversible. We associate this crossover with the Frenkel line-a recently hypothesized crossover in dynamic properties of fluids extending to arbitrarily high pressure and temperature, dividing the phase diagram into separate regions where the fluid possesses liquidlike and gaslike properties. On the liquidlike side the Raman-active vibration increases in frequency linearly as pressure is increased, as expected due to the repulsive interaction between adjacent molecules. On the gaslike side this competes with the attractive van der Waals potential leading the vibration frequency to decrease as pressure is increased.

15.
J Natl Cancer Inst ; 54(2): 319-25, 1975 Feb.
Article in English | MEDLINE | ID: mdl-1113318

ABSTRACT

An immunologic profile consisting of measurements of circulating carcinoembryonic antigen (CEA), tumor antigen-induced inhibition of monomuclear cell migration (IMM) and skin reactivity to purified protein derivative, streptokinase-streptodornase, and mumps was assessed as a diagnostic and prognostic tool in 16 patients with colon cancer. Preoperatively, 10 of 14 patients tested had elevated CEA, 12 of 12 showed tumor antigen-induced IMM, and 10 of 11 failed to react to 2 or more recall antigens. Potential surgical cure (7 patients) was accompanied by normal CEA in 4, absent tumor antigen-induced IMM in all 7, and increased skin-test reactivity in 6. Disseminated cancer (9 patients) was associated with elevated CEA in all 9, with absent IMM in all 7 and with suppressed skin-test reactivity in 6 of 9.


Subject(s)
Colonic Neoplasms/diagnosis , Adult , Aged , Carcinoembryonic Antigen/analysis , Cell Migration Inhibition , Colonic Neoplasms/immunology , Colonic Neoplasms/surgery , Female , Humans , Male , Middle Aged , Mumps/immunology , Neoplasm Metastasis , Prognosis , Skin Tests , Streptodornase and Streptokinase/immunology , Tuberculin Test
16.
Cancer Res ; 35(11 Pt. 2): 3317-9, 1975 Nov.
Article in English | MEDLINE | ID: mdl-1104143

ABSTRACT

Nutritional deficiency reduces antibody synthetic capacity. Antibody directed against tumor antigens, however, may serve either to heighten tumor immunity, as in antibody-dependent cellular cytotoxicity, or to diminish host resistance to cancer growth by "blocking" cell-mediated tumor immunity. Diets made deficient in specific amino acids are inimical to tumor growth, apparently through reduction of synthesis of blocking antibody. Thus, where tumor immune function is involved, complex and possibly paradoxical effects of nutritional status on tumor growth can be predicted.


Subject(s)
Antibodies, Neoplasm , Neoplasms/immunology , Nutritional Physiological Phenomena , Animals , Antibodies, Neoplasm/biosynthesis , Antibody Formation , Antigen-Antibody Complex , Antigens, Neoplasm , Cytotoxicity Tests, Immunologic , Diet , Dietary Proteins , Humans , Immunity, Cellular , Lymphocytes/immunology , Neoplasms, Experimental/immunology , Nutrition Disorders/immunology , Rats
17.
Arch Intern Med ; 151(7): 1373-8, 1991 Jul.
Article in English | MEDLINE | ID: mdl-2064488

ABSTRACT

BACKGROUND: --The purpose of this study is a prospective assessment of morphine sulfate administration by intermittent intravenous (IV) injections (Int-IV) vs patient-controlled analgesia (PCA) in patients in the emergency department (ED) with sickle cell crisis pain. METHODS: --Patients were at bed rest and received intravenous hydration. Linear analog scale for pain intensity and verbal pain scale, level of alertness, and vital signs were assessed prior to therapy, every 60 minutes thereafter, and at the time of discharge from the ED. Patients were randomized to Int-IV or PCA. During phase 1, patients in the Int-IV group received morphine sulfate 4 mg IV every 30 to 60 minutes as necessary for a linear analog scale for pain intensity greater than 50 mm. The patients in the PCA group received morphine sulfate 2 mg bolus then 1.0 mg with a 6-minute lockout. During phase 2, patients in the Int-IV group received morphine sulfate 8 mg IV every 30 to 60 minutes as necessary for a linear analog scale for pain intensity greater than 50 mm. The patients in the PCA group received morphine sulfate 5 mg bolus then 2.7 mg with a 10-minute lockout. Data were analyzed by unpaired t test, general linear modeling, Mann-Whitney U test, and chi 2 test. RESULTS: --During phase 1, 10 patients (28.3 +/- 7.3 years) received Int-IV and 10 patients (33.9 +/- 12.5 years) received PCA. Treatment groups did not differ significantly regarding duration of pain, amount of morphine administered, linear analog scale for pain intensity, verbal pain scale, level of alertness, or vital signs except for a significantly lower final respiratory rate with Int-IV. In phase 2, 12 patients (28.4 +/- 5.6 years) received Int-IV and 13 patients (26.8 +/- 8.1 years) received PCA. The PCA groups had a significantly shorter elapsed time between onset of pain and treatment (7.3 +/- 6.5 hours) when compared with the Int-IV group (18 +/- 16.9 hours). Treatment groups did not differ significantly with respect to total amount of morphine administered, linear analog scale for pain intensity, verbal pain scale, vital signs, or level of alertness. The PCA group had a significant reduction in length of stay in the ED during phase 2 when compared with phase 1. The ED discharge rate and the incidence of side effects did not differ significantly between groups. CONCLUSION: --At both the low- and high-dose regimens, PCA is equally safe and effective and may be used in place of Int-IV administration of morphine in the ED treatment of sickle cell crisis pain.


Subject(s)
Analgesia, Patient-Controlled , Anemia, Sickle Cell/complications , Morphine/administration & dosage , Pain/drug therapy , Adult , Aged , Ambulatory Care , Anemia, Sickle Cell/nursing , Attitude of Health Personnel , Female , Humans , Male , Middle Aged , Morphine/adverse effects , Pain/etiology , Pain Measurement , Prospective Studies , Random Allocation , Surveys and Questionnaires
18.
FEBS Lett ; 355(3): 242-6, 1994 Dec 05.
Article in English | MEDLINE | ID: mdl-7988681

ABSTRACT

The human 5-HT5A serotonin receptor has been cloned. As with the mouse and rat 5-HT5A receptors, the gene consists of two coding exons separated by a large intron. The deduced amino acid sequence of the gene reveals a protein of 357 residues which shares 93% (nucleotide) and 84% (amino acid) identity to the cloned mouse 5-HT5A receptor. We have determined the tissue distribution of the receptor by reverse transcriptase-PCR and found expression in all regions of the brain examined with little or no expression in peripheral tissues. The receptor has been transiently expressed in Cos M6 cells and exhibits a pharmacological profile closely resembling the mouse and rat 5-HT5A receptors with high, specific binding for ergotamine and methiothepin.


Subject(s)
Brain Chemistry , Receptors, Serotonin/genetics , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , GTP-Binding Proteins/metabolism , Genome, Human , Humans , Mice , Molecular Sequence Data , Radioligand Assay , Receptors, Serotonin/biosynthesis , Receptors, Serotonin/metabolism , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid , Serotonin/metabolism , Tissue Distribution , Transfection
19.
J Interferon Cytokine Res ; 21(1): 1-9, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11177575

ABSTRACT

Interleukin-18 (IL-18) and IL-12 have been shown to play an important role in the induction of interferon-gamma (IFN-gamma). IFN-gamma induces the proliferation of T cells and natural killer (NK) cells and augments the Th1 immune cascade. The role of IL-18 and IL-12 in the induction of IFN-gamma following allogeneic heart transplantation has not been described. We sought to characterize the IL-12 and IL-18 response to murine allogeneic heart transplantation, particularly with respect to IFN-gamma production and histologic transplant rejection. Forty-eight heterotopic heart transplants were performed in two groups of mice: syngeneic C3H/HeN to C3H/HeN mice and allogeneic BALB/C to C3H/HeN mice. Transplants were followed out to 2, 6, 10, and 14 days. Six transplants were performed in each group. Serum and splenic samples were used to evaluate the cytokine response by ELISA. Explanted heart tissue was processed for evidence of histologic rejection, and RT-PCR was performed to evaluate the IL-12, IL-18, and IFN-gamma signal qualitatively. Analysis of variance (ANOVA), Fisher's projected least significant difference (PLSD) was used for statistical analysis. Transplant rejection occurred in the allogeneic group histologically by day 6 and clinically by day 10. Serum IFN-gamma levels rose significantly by day 6 in the allogeneic group and then continued to rise in the splenocyte cultures. Serum IL-18 also rose significantly in the allogeneic group at day 6 compared with syngeneic group. RT-PCR revealed that the allogeneic tissue contained an increased signal for IL-12, IL-18, and IFN-gamma beginning at day 6 and peaking at day 10 after transplant. Beginning 6 days after transplantation, IL-12 and IL-18 appear to play a significant role in the induction of IFN-gamma in allogeneic heart transplants.


Subject(s)
Graft Rejection/immunology , Graft Rejection/pathology , Heart Transplantation/immunology , Heart Transplantation/pathology , Interferon-gamma/biosynthesis , Interleukin-18/biosynthesis , Animals , CD3 Complex/analysis , Graft Rejection/physiopathology , Heart Transplantation/statistics & numerical data , Interferon-gamma/blood , Interferon-gamma/genetics , Interleukin-12/blood , Interleukin-12/genetics , Interleukin-18/blood , Interleukin-18/genetics , Mice , Mice, Inbred BALB C , Mice, Inbred C3H , Reverse Transcriptase Polymerase Chain Reaction , Spleen/cytology , Spleen/immunology , Spleen/metabolism , Transplantation, Homologous , Transplantation, Isogeneic
20.
J Med Chem ; 38(18): 3524-35, 1995 Sep 01.
Article in English | MEDLINE | ID: mdl-7658439

ABSTRACT

The optimization of in vitro activity and oral potency and duration of action in vivo is described for three novel structural types of platelet-activating factor (PAF) antagonist: [1,5]benzodiazepines 5-12 onto which a variety of other heterocyclic rings were fused, pyrido[2,3-b][1,4]-diazepinones 13-26, and pyrazolo[3,4-b][1,4]diazepinones 27-46. Compounds 5-12 were prepared by elaboration of the [1,5]benzodiazepine-2-thiones 47 and 48, and 13-46 were prepared by cyclocondensation reactions of a variety of 2,3-diaminopyridine and 4,5-diaminopyrazole derivatives with ethyl 4'-(2-methylimidazo[4,5-c] pyrid-1-yl)benzoylacetate (53). The presence of imine-enamine tautomerism was observed in certain diazepine derivatives and is discussed. Structure-activity relationships were evaluated where PAF antagonist activity was measured in vitro by determining the concentration of compound (IC50) required to inhibit PAF-induced aggregation of rabbit washed platelets and in vivo by determining the oral dose (ED50) which protected mice from a lethal injection of PAF. In addition, the duration of action in conscious dogs as measured by determining the oral dose of selected compounds required to inhibit completely PAF-induced whole blood aggregation ex vivo. The most potent compound was 1,6,7,8-tetrahydro-1,8-dimethyl-5-[4-(2-methylimidazo [4,5-c]pyrid-1-yl)phenyl]-7-oxo-3-(3-pyridyl) pyrazolo[3,4-b][1,4]diazepine (43, UK-91,473) (IC50 = 2.4 nM, ED50 = 0.01 mg/kg po), which was found to be significantly more potent in vivo (murine lethality) than the dihydropyridine PAF antagonist 4-(2-chlorophenyl)-1,4-dihydro-3-(ethoxycarbonyl)-6-methyl- 4-[(2-methylimidazo[4,5-c]pyrid-1-yl)phenyl]-5- [N-(2-pyridyl)carbamoyl]pyridine (4, UK-74,505) (ED50 = 0.26 mg/kg po). Compound 43 also possessed a longer duration of action than compound 4 in the conscious dog at one-fourth of the dose. The crystal structure of compound 43, established by X-ray diffraction, is reported.


Subject(s)
Azepines/pharmacology , Benzodiazepines/pharmacology , Dihydropyridines/pharmacology , Imidazoles/pharmacology , Platelet Activating Factor/antagonists & inhibitors , Pyridines/pharmacology , Animals , Azepines/chemistry , Benzene/chemistry , Benzodiazepines/chemistry , Dihydropyridines/chemistry , Dogs , Imidazoles/chemistry , In Vitro Techniques , Mice , Platelet Activating Factor/pharmacology , Platelet Aggregation Inhibitors/pharmacology , Pyrazoles/chemistry , Pyridines/chemistry , Rabbits , Structure-Activity Relationship , X-Ray Diffraction
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