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1.
Pharmazie ; 77(7): 248-254, 2022 09 01.
Article in English | MEDLINE | ID: mdl-36199179

ABSTRACT

Recently, pretreatment with immune checkpoint inhibitors (ICIs) has been shown to enhance the therapeutic effects of the combination therapy of ramucirumab (RAM) and docetaxel (DTX); however, its influence on the drug's side effects remains unclear. This study investigated the influence of pretreatment with ICIs on the incidence of neutropenia caused by RAM + DTX therapy in patients with non-small cell lung cancer (NSCLC). Patients with NSCLC who received RAM + DTX therapy at Gifu Prefectural General Medical Center between April 2016 and December 2020 were enrolled. Retrospective data regarding age, sex, performance status and detailed treatment history, among others, at treatment initiation were collected from the patients' electronic medical records. Additionally, data on the course number of RAM + DTX therapy, supportive therapy and blood biochemical parameters, including leukocyte and neutrocyte counts, during the treatment period were collected. We identified 41 patients receiving RAM + DTX therapy. Among the more than grade 3 adverse events caused by this therapy, neutropenia was the most common (78.1%). Despite the fact that all previous risk factors influencing this incidence rate had corresponded, the only factor influencing the incidence rate of neutropenia more than grade 3 was ICI treatment history. A difference in the incidence of neutropenia more than grade 3 in the Kaplan-Meier curve was observed between patients with and without ICI pretreatment history (p = 0.037). The pretreatment history of ICI therapy affects the incidence of neutropenia caused by RAM + DTX therapy in patients with NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Neutropenia , Antibodies, Monoclonal, Humanized , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Carcinoma, Non-Small-Cell Lung/drug therapy , Docetaxel/adverse effects , Humans , Immune Checkpoint Inhibitors , Lung Neoplasms/drug therapy , Neutropenia/chemically induced , Neutropenia/drug therapy , Neutropenia/epidemiology , Retrospective Studies , Ramucirumab
3.
Clin Radiol ; 76(6): 472.e1-472.e9, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33752883

ABSTRACT

AIM: To explore changes in left ventricular (LV) function and the relationship of these changes with myocardial blood flow (MBF) evaluated by 13N-ammonia hybrid positron-emission tomography (PET)/magnetic resonance imaging (MRI) during vasodilator stress in patients with suspected coronary artery disease (CAD). MATERIALS AND METHODS: Fifty-two consecutive patients with suspected CAD, who underwent 13N-ammonia PET/MRI, were enrolled. Vasodilator stress was induced by intravenous injection of adenosine. MBF and coronary flow reserve (CFR) were calculated from dynamic acquisition of 13N-ammonia PET. LV function was evaluated by MRI both at rest and during vasodilator stress. An abnormal perfusion on myocardial images was defined as a summed difference score of ≥4. RESULTS: MRI showed that the LV end-diastolic volume, LV end-systolic volume, and LV ejection fraction (LVEF) remained unchanged during vasodilator stress in all patients (n=52) as well as in the patients with CFR of <2 (n=27), stress MBF of <1.3 ml/g/min (n=28), abnormal myocardial perfusion (n=30), and more than one diseased vessel (n=46). In only four patients, the LVEF measured by MRI decreased by >5% during vasodilator stress. In these four patients, CFR was lower (1.57 ± 0.12 versus 2.18 ± 0.86, p<0.01) and the number of diseased vessels was higher (2.75 ± 0.50 versus 1.48 ± 0.92, p<0.01) than in patients without post-stress LV dysfunction. CONCLUSION: The LV volume and systolic function evaluated by cardiac MRI remained unchanged during vasodilator stress; however, LV dysfunction during vasodilator stress may occur in patients with severe CAD.


Subject(s)
Coronary Artery Disease/diagnostic imaging , Exercise Test/methods , Magnetic Resonance Imaging/methods , Multimodal Imaging/methods , Nitrogen Radioisotopes , Positron-Emission Tomography/methods , Ventricular Dysfunction, Left/diagnostic imaging , Ammonia , Coronary Artery Disease/complications , Coronary Artery Disease/physiopathology , Female , Humans , Male , Middle Aged , Vasodilator Agents , Ventricular Dysfunction, Left/complications , Ventricular Dysfunction, Left/physiopathology
6.
Br J Anaesth ; 122(1): 153, 2019 01.
Article in English | MEDLINE | ID: mdl-30579397

ABSTRACT

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief of British Journal of Anaesthesia. The study is retracted for the following reasons: Y Saitoh provided a statement in a personal communication to a member of the editorial board of British Journal of Anaesthesia that the study was not approved by the Institutional Review Board and that no evidence exists to support the study findings.

7.
Radiat Prot Dosimetry ; 170(1-4): 213-7, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27150515

ABSTRACT

A thin silicon sensor has been developed for active neutron personal dosemeters for use by aircrews and first responders. This thin silicon sensor is not affected by the funneling effect, which causes detection of cosmic protons and over-response to cosmic neutrons. There are several advantages to the thin silicon sensor: a decrease in sensitivity to gamma rays, an improvement of the energy detection limit for neutrons down to 0.8 MeV and an increase in the sensitivity to fast neutrons. Neutron response functions were experimentally obtained using 2.5 and 5 MeV monoenergy neutron beams and a (252)Cf neutron source. Simulation results using the Monte Carlo N-Particle transport code agree quite well with the experimental ones when an energy deposition region shaped like a circular truncated cone is used in place of a cylindrical region.


Subject(s)
Cosmic Radiation , Neutrons , Radiation Dosimeters , Radiometry/instrumentation , Radiometry/methods , Silicon/chemistry , Algorithms , Californium , Computer Simulation , Fast Neutrons , Gamma Rays , Humans , Monte Carlo Method , Occupational Exposure/analysis , Polyethylene , Radiation Dosage , Radiation Protection , Software
8.
Transplant Proc ; 48(3): 929-32, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27234770

ABSTRACT

BACKGROUND: Granulocyte and monocyte adsorptive apheresis (GMAA) is widely used as a treatment for active ulcerative colitis (UC) in Japan. Much attention has been paid to the possibility of GMAA for the treatment and control of cytomegalovirus (CMV) reactivation in patients with refractory UC and concomitant CMV infection. In this study, the effects of the combination of GMAA and antiviral therapy were examined in renal transplant recipients with concomitant CMV infection. METHODS: Combination therapy of GMAA and antiviral drugs was performed 9 times in 7 renal transplant recipients with concomitant CMV infection. Four of the cases were positive for CMV-IgG, and 3 were negative. The clinical presentation of CMV infection was viremia in 6 cases and disease (CMV retinitis) in 1 case. CMV infection was diagnosed by using an antigenemia assay (C7-HRP). GMAA session was performed once, and the duration of the session was 120 min. Immediately after the GMAA session, ganciclovir was administered at 5 mg/kg/body weight. CMV infection was monitored based on C7-HRP and CMV-DNA in the peripheral blood samples. RESULTS: All cases became negative for C7-HRP and CMV-DNA within 21 days (median, 14 days; range, 3-21 days) and 17 days (median, 6 days; range, 3-17 days), respectively, after starting the combination therapy. No side effects of GMAA were observed. CONCLUSIONS: This case series found that GMAA in combination with antiviral drugs may shorten the duration of treatment against CMV infection in renal transplant recipients. Further studies in a larger number of patients are required to confirm these results.


Subject(s)
Antiviral Agents/therapeutic use , Blood Component Removal , Cytomegalovirus Infections/therapy , Granulocytes , Kidney Transplantation , Monocytes , Adsorption , Adult , Aged , Combined Modality Therapy , Cytomegalovirus Infections/complications , Cytomegalovirus Infections/diagnosis , Female , Ganciclovir/therapeutic use , Humans , Japan , Kidney Failure, Chronic/surgery , Kidney Failure, Chronic/virology , Male , Middle Aged
9.
Free Radic Res ; 48(6): 649-58, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24568262

ABSTRACT

Vitamin E deficiency induces neuronal dysfunction and while oxidative stress is likely to be involved in mediating this process, the detailed mechanisms remain to be elucidated. Previously, we found axonal degeneration in the hippocampal CA1 region in vitamin E-deficient mice of 6 months of age (long-term). However, 3 month-old (short-term) vitamin E-deficient mice did not exhibit axonal degeneration in same region. In order to characterize the mechanisms involved in axonal degeneration in long-term vitamin E-deficient mice, we examined changes in microtubule-related proteins. Long-term vitamin E-deficiency led to significantly increased expression of the phosphorylated form of collapsin response mediator protein (CRMP)-2 compared to short-term deficiency. It is well known that CRMP-2 plays a crucial role in the maintenance of neurite function. Similarly, long-term vitamin E-deficiency significantly decreased the expression of silent mating type information regulation (SIRT)-2 mRNA compared to short-term deficiency. SIRT-2 belongs to a family of class III histone deacetylases (HDACs) and functions in the deacetylation of tubulins. Furthermore, the expression of microtubule-associated protein light chain (MAP-LC)3-2, which is a key autophagy protein was significantly higher in the short-term vitamin E-deficiency than the long-term deficiency. These results indicate that the mechanisms of axonal injury in long-term vitamin E-deficient mice are related to dysfunction in microtubules assembly via alterations in microtubule-related proteins and autophagy.


Subject(s)
Glycogen Synthase Kinase 3/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Nerve Degeneration/metabolism , Nerve Tissue Proteins/metabolism , Sirtuin 2/biosynthesis , Vitamin E Deficiency , Animals , Autophagy , Axons/pathology , Brain/metabolism , CA1 Region, Hippocampal/pathology , Cell Line, Tumor , Diet , Glycogen Synthase Kinase 3 beta , Intercellular Signaling Peptides and Proteins/biosynthesis , Mice , Mice, Inbred C57BL , Microtubule Proteins/metabolism , Microtubule-Associated Proteins/biosynthesis , Microtubules/metabolism , Microtubules/pathology , Mitochondria/metabolism , Nerve Tissue Proteins/biosynthesis , Neurites/pathology , Oxidative Stress , Phosphorylation , RNA, Messenger/biosynthesis , Sirtuin 2/genetics , Vitamin E/metabolism
10.
Neurology ; 77(20): 1819-26, 2011 Nov 15.
Article in English | MEDLINE | ID: mdl-22013178

ABSTRACT

OBJECTIVE: Muscle-specific receptor tyrosine kinase (MuSK) antibody-positive myasthenia gravis (MG) accounts for 5%-15% of autoimmune MG. MuSK mediates the agrin-signaling pathway and also anchors the collagenic tail subunit (ColQ) of acetylcholinesterase (AChE). The exact molecular target of MuSK-immunoglobulin G (IgG), however, remains elusive. As acetylcholine receptor (AChR) deficiency is typically mild and as cholinesterase inhibitors are generally ineffective, we asked if MuSK-IgG interferes with binding of ColQ to MuSK. METHODS: We used 3 assays: in vitro overlay of the human ColQ-tailed AChE to muscle sections of Colq-/- mice; in vitro plate-binding assay to quantitate binding of MuSK to ColQ and to LRP4; and passive transfer of MuSK-IgG to mice. RESULTS: The in vitro overlay assay revealed that MuSK-IgG blocks binding of ColQ to the neuromuscular junction. The in vitro plate-binding assay showed that MuSK-IgG exerts a dose-dependent block of MuSK binding to ColQ by but not to LRP4. Passive transfer of MuSK-IgG to mice reduced the size and density of ColQ to ∼10% of controls and had a lesser effect on the size and density of AChR and MuSK. CONCLUSIONS: As lack of ColQ compromises agrin-mediated AChR clustering in Colq-/- mice, a similar mechanism may lead to AChR deficiency in MuSK-MG patients. Our experiments also predict partial AChE deficiency in MuSK-MG patients, but AChE is not reduced in biopsied NMJs. In humans, binding of ColQ to MuSK may be dispensable for clustering ColQ, but is required for facilitating AChR clustering. Further studies will be required to elucidate the basis of this paradox.


Subject(s)
Acetylcholinesterase/metabolism , Antibodies, Blocking/pharmacology , Autoantibodies/pharmacology , Binding Sites, Antibody , Collagen/metabolism , Muscle Proteins/metabolism , Receptor Protein-Tyrosine Kinases/antagonists & inhibitors , Receptor Protein-Tyrosine Kinases/metabolism , Receptors, Cholinergic/metabolism , Animals , Collagen/antagonists & inhibitors , Mice , Mice, Knockout , Muscle Proteins/antagonists & inhibitors , Myasthenia Gravis, Autoimmune, Experimental/chemically induced , Myasthenia Gravis, Autoimmune, Experimental/immunology , Myasthenia Gravis, Autoimmune, Experimental/metabolism , Receptor Protein-Tyrosine Kinases/immunology , Receptors, Cholinergic/immunology
11.
Aliment Pharmacol Ther ; 32(7): 908-15, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20839389

ABSTRACT

BACKGROUND: Endoscopic submucosal dissection (ESD) using short needle knives is safe and effective, but bleeding is a problem due to low haemostatic capability. AIM: To assess the performance of a novel ball-tipped needle knife (Flush knife-BT) for ESD with particular emphasis on haemostasis. METHODS: A case-control study to compare the performance for ESD of 30 pairs of consecutive early gastrointestinal lesions (oesophagus: 12, stomach: 32, colorectum: 16) with standard Flush knife (F) vs. Flush knife-BT (BT). Primary outcome was efficacy of intraprocedure haemostasis. Secondary outcomes included procedure time, procedure speed (dividing procedure time into the area of resected specimen), en bloc resection rate and recurrence rate. RESULTS: Median intraoperative bleeding points and bleeding points requiring haemostatic forceps were smaller in the BT group than in the F group (4 vs. 8, P < 0.0001, 0 vs. 3, P < 0.0001). There was no difference between groups for procedure time; however, procedure speed was shorter in the BT group (P = 0.0078). En bloc and en bloc R0 resection rates were 100%, with no perforation or post-operative bleeding. No recurrence was observed in either group at follow-up 1 year postprocedure. CONCLUSIONS: Ball-tipped Flush knife (Flush knife-BT) appears to improve haemostatic efficacy and dissection speed compared with standard Flush knife.


Subject(s)
Dissection/instrumentation , Endoscopy/instrumentation , Gastrointestinal Neoplasms/surgery , Gastrointestinal Tract/surgery , Surgical Instruments/standards , Aged , Case-Control Studies , Equipment Design , Female , Humans , Male , Statistics as Topic , Treatment Outcome
12.
Clin Exp Immunol ; 162(2): 315-24, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20819092

ABSTRACT

Immunoglobulins (Igs) play important immunomodulatory effects on allergic asthma. Among these, IgG has been reported to regulate allergic inflammation in previous studies about immunotherapy and intravenous immunoglobulin therapy. In this study, to examine the immunomodulatory mechanisms of IgG and FcRs we evaluated the effects of intravenous (i.v.) rabbit IgG administration (IVIgG) on allergic airway inflammation and lung antigen-presenting cells (APCs) in a murine model of ovalbumin (OVA) sensitization and challenge. In OVA-challenged mice, IVIgG attenuated airway eosinophilia, airway hyperresponsiveness and goblet cell hyperplasia and also inhibited the local T helper type (Th) 2 cytokine levels. Additionally, IVIgG attenuated the proliferation of OVA-specific CD4(+) T cells transplanted into OVA-challenged mice. Ex vivo co-culture with OVA-specific CD4(+) cells and lung CD11c(+) APCs from mice with IVIgG revealed the attenuated transcription level of Th2 cytokines, suggesting an inhibitory effect of IVIgG on CD11c(+) APCs to induce Th2 response. Next, to analyse the effects on Fcγ receptor IIb and dendritic cells (DCs), asthmatic features in Fcγ receptor IIb-deficient mice were analysed. IVIgG failed to attenuate airway eosinophilia, airway inflammation and goblet cell hyperplasia. However, the lacking effects of IVIgG on airway eosinophilia in Fcγ receptor IIb deficiency were restored by i.v. transplantation of wild-type bone marrow-derived CD11c(+) DCs. These results demonstrate that IVIgG attenuates asthmatic features and the function of lung CD11c(+) DCs via Fcγ receptor IIb in allergic airway inflammation. Targeting Fc portions of IgG and Fcγ receptor IIb on CD11c(+) DCs in allergic asthma is a promising therapeutic strategy.


Subject(s)
Asthma/therapy , CD11c Antigen/metabolism , Dendritic Cells/drug effects , Immunoglobulin G/pharmacology , Immunoglobulins, Intravenous/pharmacology , Receptors, IgG/genetics , Adoptive Transfer , Animals , Antigen Presentation/drug effects , Antigen Presentation/immunology , Asthma/immunology , Asthma/pathology , Asthma/physiopathology , Bronchial Hyperreactivity/physiopathology , Bronchial Hyperreactivity/prevention & control , Bronchoalveolar Lavage Fluid/chemistry , Bronchoalveolar Lavage Fluid/cytology , CD4-Positive T-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Cell Count , Cell Differentiation/drug effects , Cell Differentiation/immunology , Cell Proliferation , Cytokines/metabolism , Dendritic Cells/immunology , Dendritic Cells/metabolism , Dendritic Cells/transplantation , Disease Models, Animal , Eosinophils/cytology , Female , Immunoglobulin E/blood , Immunoglobulin G/therapeutic use , Immunoglobulins, Intravenous/therapeutic use , Immunologic Factors/pharmacology , Immunologic Factors/therapeutic use , Inflammation/immunology , Inflammation/pathology , Inflammation/prevention & control , Mice , Mice, Inbred C57BL , Ovalbumin/immunology , Specific Pathogen-Free Organisms , Th2 Cells/immunology
14.
Clin Exp Immunol ; 160(2): 283-92, 2010 May.
Article in English | MEDLINE | ID: mdl-20030669

ABSTRACT

Vitamin K is a family of fat-soluble compounds including phylloquinone (vitamin K1), menaquinone (vitamin K2) and menadione (vitamin K3). Recently, it was reported that vitamin K, especially vitamins K1 and K2, exerts a variety of biological effects, and these compounds are expected to be candidates for therapeutic agents against various diseases. In this study, we investigated the anti-inflammatory effects of vitamin K3 in in vitro cultured cell experiments and in vivo animal experiments. In human embryonic kidney (HEK)293 cells, vitamin K3 inhibited the tumour necrosis factor (TNF)-alpha-evoked translocation of nuclear factor (NF)-kappaB into the nucleus, although vitamins K1 and K2 did not. Vitamin K3 also suppressed the lipopolysaccharide (LPS)-induced nuclear translocation of NF-kappaB and production of TNF-alpha in mouse macrophage RAW264.7 cells. Moreover, the addition of vitamin K3 before and after LPS administration attenuated the severity of lung injury in an animal model of acute lung injury/acute respiratory distress syndrome (ARDS), which occurs in the setting of acute severe illness complicated by systemic inflammation. In the ARDS model, vitamin K3 also suppressed the LPS-induced increase in the serum TNF-alpha level and inhibited the LPS-evoked nuclear translocation of NF-kappaB in lung tissue. Despite marked efforts, little therapeutic progress has been made, and the mortality rate of ARDS remains high. Vitamin K3 may be an effective therapeutic strategy against acute lung injury including ARDS.


Subject(s)
Acute Lung Injury/drug therapy , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Lipopolysaccharides/toxicity , NF-kappa B/antagonists & inhibitors , Vitamin K 3/therapeutic use , Acute Lung Injury/chemically induced , Acute Lung Injury/genetics , Acute Lung Injury/metabolism , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Bronchoalveolar Lavage Fluid/cytology , Cells, Cultured/drug effects , Drug Evaluation, Preclinical , Gene Expression Regulation/drug effects , Humans , Kidney , Lung/immunology , Lung/metabolism , Lung/pathology , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/metabolism , Male , Mice , Mice, Inbred C57BL , NF-kappa B/metabolism , Neutrophils/drug effects , Tumor Necrosis Factor-alpha/biosynthesis , Tumor Necrosis Factor-alpha/metabolism , Vitamin K 1/pharmacology , Vitamin K 1/therapeutic use , Vitamin K 2/pharmacology , Vitamin K 2/therapeutic use , Vitamin K 3/pharmacology
15.
Intern Med J ; 39(6): 408-11, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19580620

ABSTRACT

Imatinib mesylate (IM) is currently used as the first therapeutic choice against chronic myelogenous leukaemia (CML). Because IM poorly penetrates the blood-brain barrier, IM-treated CML patients may have a potential risk of central nervous system (CNS) involvement. Here we report a case with lymphoid blast crisis isolated only in CNS after bacterial meningitis, although the patient achieved and maintained complete cytogenetic response by IM therapy. It is important to consider isolated CNS blast crisis as a possible event in IM-treated CML patients.


Subject(s)
Central Nervous System Diseases/metabolism , Central Nervous System/metabolism , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism , Piperazines/therapeutic use , Pyrimidines/therapeutic use , Benzamides , Central Nervous System/drug effects , Central Nervous System Diseases/chemically induced , Humans , Imatinib Mesylate , Male , Meningitis, Bacterial/chemically induced , Meningitis, Bacterial/metabolism , Middle Aged , Piperazines/adverse effects , Pyrimidines/adverse effects
16.
Vet Parasitol ; 158(1-2): 152-8, 2008 Nov 25.
Article in English | MEDLINE | ID: mdl-18849118

ABSTRACT

Enzyme-linked immunosorbent assay (ELISA) and Western blot were used to investigate the pattern of antibody responses of six bovines infested twelve times with Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae) (six heavy infestations followed by six light infestations) against salivary gland, gut and larvae extracts. During heavy infestations, bovine IgG levels were shown to be higher, and a decrease in the number and weight of ticks that completed the parasitic cycle was observed. The pattern changed starting from the seventh infestation, showing a decrease in IgG levels. An initial increase followed by a significant decrease in the proportion of ticks that completed the parasitic cycle was also observed from the seventh infestation. The number of molecules recognized by Western blot was higher from sera collected following heavy infestations than after light infestations, although a great variation in the profiles detected could be seen when the bovines were compared. These results indicate that IgG responses to different tick antigens may not be generally associated with bovine resistance, and that infestation levels modulate the magnitude of humoral responses and possibly the immune mechanisms in the natural acquisition of tick resistance.


Subject(s)
Cattle Diseases/immunology , Immunoglobulin G/blood , Rhipicephalus/immunology , Tick Infestations/veterinary , Animals , Animals, Wild , Blotting, Western/methods , Blotting, Western/veterinary , Cattle , Cattle Diseases/blood , Cattle Diseases/parasitology , Enzyme-Linked Immunosorbent Assay/methods , Enzyme-Linked Immunosorbent Assay/veterinary , Immune Sera/immunology , Male , Random Allocation , Rhipicephalus/chemistry , Tick Infestations/blood , Tick Infestations/immunology , Tick Infestations/parasitology , Time Factors
19.
Clin Exp Allergy ; 37(3): 339-47, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17359384

ABSTRACT

BACKGROUND: Bacterial infection occasionally exacerbates asthma, although the cellular and molecular mechanisms have not been well defined. An involvement of mast cells has been suggested, as lipopolysaccharides (LPS)-induced cytokine production from mast cells in vitro. OBJECTIVE: This study was undertaken to examine the effects of LPS inhalation on mast cell functions and allergen-specific immune responses in a murine model of asthma. METHODS: Female BALB/c mice or mast cell-deficient W/W(v) mice were immunized intraperitoneally with ovalbumin (OVA). Mice were challenged with aerosolized OVA or OVA with LPS daily from day 21 to day 24. Twenty-four hours after the last challenge, airway inflammation and OVA-specific immune responses were examined. Allergen-specific T cell responses were further analysed by adoptively transferring OVA-specific CD4(+) T cells. Expression of chemokines in the lung was also examined. RESULTS: LPS inhalation with OVA resulted in exacerbated airway infiltration, which was not evident in mast cell-deficient mice. IL-5 production by mast cells in the lung was enhanced by LPS inhalation. OVA-specific IgE production as well as proliferation, cytokine production and local infiltration of OVA specific T-helper lymphocytes type 2 (Th2) were also enhanced. Up-regulated expression of Th2- and/or eosinophil-attracting chemokines was observed in the lung of mice inhalated with LPS. CONCLUSIONS: LPS inhalation exacerbates airway inflammation, which is accompanied by mast cell activation and enhanced Th2 responses. These observations provide clues towards understanding the mechanisms of bacterial infection-induced exacerbation of the clinical features of asthma.


Subject(s)
Asthma/immunology , Lipopolysaccharides/adverse effects , Mast Cells/immunology , Th2 Cells/immunology , Allergens/immunology , Animals , Bacterial Infections/immunology , Cytokines/immunology , Disease Models, Animal , Female , Lipopolysaccharides/immunology , Mice , Mice, Inbred BALB C , Respiratory Tract Infections/immunology
20.
Article in English | MEDLINE | ID: mdl-16798037

ABSTRACT

Glutathione S-transferases (GSTs) are enzymes that act in excretion of physiologic and xenobiotic substances, protecting cells against chemical toxicity and stress. In this work, we characterized the enzymatic activity of GST in eggs and larvae of cattle tick Boophilus microplus, on different days after oviposition and eclosion. The results showed that the GST activity varied depending on the time elapsed after oviposition and eclosion. Molecules involved in mechanism of protection from oxidative stress are correlated with the increase in GST activity. The oxygen consumption kinetics showed a positive correlation with the increase in GST activity during embryogenesis. A high content of thiobarbituric acid reactive substances were observed in egg and larva extracts, indicating that ticks face high oxidative stress during embryogenesis and aging. In eggs and larvae, GST activity can be correlated to kinetic parameters of oxidative stress such as catalase and glutathione. In addition, GST activity showed strong positive correlation with lipid peroxidation, an indication that it plays a role in oxidant defences in eggs.


Subject(s)
Ixodidae/metabolism , Lipid Peroxidation , Ovum/metabolism , Oxidative Stress , Oxygen Consumption , Amitrole/pharmacology , Animals , Catalase/antagonists & inhibitors , Catalase/metabolism , Enzyme Inhibitors/pharmacology , Female , Glutathione/metabolism , Glutathione Transferase/metabolism , Larva/metabolism
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