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1.
Environ Pollut ; 291: 118130, 2021 Dec 15.
Article in English | MEDLINE | ID: mdl-34562691

ABSTRACT

Microplastics pollution in marine environments is concerning. Microplastics persist and accumulate in various sections of the ocean where they present opportunity for micropollutant accumulation and microbial colonisation. Even though biofilm formation on plastics was first reported in the 1970's, it is only in recent years were plastic associated biofilms have gained research attention. Plastic surfaces pose a problem as they are a niche ready for colonisation by diverse biofilm assemblages, composed of specific bacterial communities and putative pathogens prone to acquiring ARGs and resistance in the biofilm. However, the nature of antibiotic resistance on aquatic plastic debris is not yet fully understood and remains a concern. Given the inevitable increase of plastic production and waste generation, microplastics released into the environment may prove to be problematic. This review explores microplastic waste in the ocean and possible concerns that may arise from the presence of microplastics in conjunction with favourable conditions for the development and dispersal of antibiotic resistance in the ocean and food web.


Subject(s)
Microplastics , Water Pollutants, Chemical , Bacteria/genetics , Environmental Monitoring , Environmental Pollution , Oceans and Seas , Plastics , Water Pollutants, Chemical/analysis
2.
Anaesthesist ; 61(5): 444-51, 2012 May.
Article in German | MEDLINE | ID: mdl-22576993

ABSTRACT

BACKGROUND: There is no nationwide evaluation of the quality of anaesthesia in Germany. Thus, the aim of this study was to perform analyses using administrative routine data relating to this topic. METHODS: Nationwide hospital claims data of patients insured with the local healthcare insurance fund (AOK) in the year 2007 were analyzed. Indicators from International Statistical Classification of Diseases and Related Health Problems-10, German modification (ICD-10-GM) diagnosis codes for possible anaesthesia complications were selected. RESULTS: Based on the present data, it was not possible to validate indicators which can be applied to detect the quality of anaesthesia. CONCLUSIONS: Administrative data seem to be an appropriated basis for measurement of quality of outcome in anaesthesiology. Further investigations should be performed to include the diagnosis present on admission. Moreover, there is a need for comparing routine data to the standardized data set, known as the "core data set anaesthesia".


Subject(s)
Anesthesia/standards , Appendectomy/standards , Colon/surgery , Digestive System Surgical Procedures/standards , Quality Assurance, Health Care/methods , Airway Management/adverse effects , Anesthesia/adverse effects , Anesthetics/adverse effects , Germany , Humans , Insurance Claim Review , International Classification of Diseases , Patient Safety , Treatment Outcome
3.
Transpl Infect Dis ; 11(3): 235-40, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19302273

ABSTRACT

Mycophenolate mofetil (MMF) is commonly used in immunosuppressive regimens for solid organ transplantation. There is evidence that the hydrolyzed active agent mycophenolic acid (MPA) causes the endothelial depletion of intracellular guanosine 5'-triphosphate (GTP) levels. This depletion may cause inactivation of nicotinamide adenine dinucleotide phosphate oxidase. The purpose of the present study was to examine the impact of MPA on the neutrophil respiratory burst and phagocytic activity using flow cytometry. In whole blood of healthy volunteers, 2 different doses of MPA (1 and 10 mumol/L) did not alter hydrogen peroxide production of neutrophils induced by receptor-dependent activators. In contrast, MPA inhibits the protein kinase C (PKC)-mediated hydrogen peroxide production by phorbol 12-myristate 13-acetate (PMA) in a time-dependent manner (negative: 21.17 +/- 1.64 vs. 120 min: 14.46 +/- 1.28 mean fluorescence intensity, incubation with 1 mumol/L MPA). In conclusion, our results corroborated that the neutrophil respiratory burst activity of healthy volunteers, induced by either formyl-methionyl-leucylphenylalanine (fMLP), priming with tumor necrosis factor alpha followed by fMLP or Escherichia coli and neutrophil phagocytic capacity, were not significantly affected after MPA treatment. We also could demonstrate that the hydrogen peroxide production of neutrophils decreased in response to the PKC activator PMA in a time-dependent manner.


Subject(s)
Mycophenolic Acid/pharmacology , Neutrophils/drug effects , Phagocytosis/drug effects , Respiratory Burst/drug effects , Tetradecanoylphorbol Acetate/pharmacology , Adult , Female , Flow Cytometry , Humans , Hydrogen Peroxide/metabolism , Male , Neutrophils/immunology , Neutrophils/metabolism , Young Adult
4.
J Neuroimmunol ; 159(1-2): 113-8, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15652409

ABSTRACT

Although it is known that macrophages take up serotonin, a specific monoamine transporter has not been identified in macrophages. In this study, mRNA coding for the serotonin transporter (SERT) was detected with the reverse transcription-polymerase chain reaction (RT-PCR) in recruited mouse peritoneal macrophages. Sequencing confirmed the identity of the RT-PCR product to mouse SERT mRNA. SERT protein was detected by Western blotting. Macrophage activation with lipopolysaccharide had no effect on expression of SERT mRNA or protein. Consistent with expression of a functional SERT, specific uptake of (3)H-serotonin in macrophages was sodium dependent and inhibited by fluoxetine (IC(50) 6.9 nM) and desipramine (IC(50) 32 nM) but not by nisoxetine or reserpine.


Subject(s)
Macrophages, Peritoneal/metabolism , Membrane Glycoproteins/biosynthesis , Membrane Transport Proteins/biosynthesis , Nerve Tissue Proteins/biosynthesis , Serotonin/metabolism , Animals , Blotting, Western , COS Cells , Female , Lipopolysaccharides/pharmacology , Macrophage Activation , Macrophages, Peritoneal/chemistry , Macrophages, Peritoneal/immunology , Membrane Glycoproteins/antagonists & inhibitors , Membrane Glycoproteins/genetics , Membrane Glycoproteins/isolation & purification , Membrane Transport Modulators , Membrane Transport Proteins/antagonists & inhibitors , Membrane Transport Proteins/genetics , Membrane Transport Proteins/isolation & purification , Mice , Mice, Inbred CBA , Molecular Sequence Data , Nerve Tissue Proteins/antagonists & inhibitors , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/isolation & purification , RNA, Messenger/biosynthesis , Reverse Transcriptase Polymerase Chain Reaction , Serotonin Antagonists/pharmacology , Serotonin Plasma Membrane Transport Proteins , Tritium/metabolism
5.
Crit Care Nurs Clin North Am ; 13(2): 319-27, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11866412

ABSTRACT

Widespread application of EBPM by bedside providers is needed to demonstrate the success of pain management strategies on patient outcomes. This goal is not easy to attain and generally requires time, patience, and a multidisciplinary team approach. Implementation and evaluation of pain interventions increase awareness and knowledge of pain management strategies and can result in an overall improvement in pain management. The literature and guidelines recommend the use of specific strategies to ensure practice change. Studies suggest that a more intensive or "active" effort to alter practice is generally most successful. The pain management program should be marketed so that both the health care providers and patients are aware of the goal and resources available. It may take 3 to 5 years to infuse the change and see the improvement. Reinfusion over time also needs to be planned. Bedside practitioners need to have knowledge of the current best evidence in pain management of the critically ill patient. Barriers to implementation must be eliminated so that practitioners can conscientiously and judiciously implement strategies to relieve pain. Opinion leaders and change agents need to be available to continually champion EBPM, and prompts to ask about pain should be provided to practitioners and patients.


Subject(s)
Diffusion of Innovation , Evidence-Based Medicine , Intensive Care Units/organization & administration , Pain/prevention & control , Health Knowledge, Attitudes, Practice , Humans , Intensive Care Units/standards , Organizational Innovation , Patient Care Team
6.
Eur J Obstet Gynecol Reprod Biol ; 82(1): 101-6, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10192496

ABSTRACT

OBJECTIVE: Are there differences in self-concept and body image in patients with cancer recurrence in comparison to patients with complete remission? What impact has cancer recurrence on use, users and non-users of unconventional cancer therapies? PATIENTS AND METHODS: One hundred and nine patients with no evidence of disease after gynaecological cancer and sixty-one patients with recurrent disease were analysed for self-concept with the Frankfurter Selbstkonzeptskalen and body image with the Frankfurter Körperkonzeptskalen. Use and motivation for unconventional therapies was assessed with a questionnaire. RESULTS: With respect to frequency of use and expected benefits of unconventional therapies no differences were observed between the groups. However, cancer recurrence was found to induce considerable changes of self-concept and body image, some indicating even positive changes due to cancer recurrence. CONCLUSION: It may be beneficial to consider body therapy and psychotherapy as a mean to improve body image and self-esteem in cases with cancer recurrence.


Subject(s)
Body Image , Complementary Therapies , Genital Neoplasms, Female/psychology , Neoplasm Recurrence, Local/psychology , Self Concept , Adult , Aged , Breast Neoplasms/psychology , Endometrial Neoplasms/psychology , Female , Genital Neoplasms, Female/therapy , Humans , Middle Aged , Ovarian Neoplasms/psychology , Remission Induction , Stress, Psychological/psychology , Surveys and Questionnaires , Uterine Cervical Neoplasms/psychology , Vulvar Neoplasms/psychology
7.
Br J Cancer ; 79(3-4): 637-9, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10027342

ABSTRACT

Dexamethasone (20 mg) or its equivalent in combination with 5-HT3 antagonists appears to be the gold-standard dose for antiemetic prophylaxis. Additional to concerns about the use of corticosteroids with respect to enhanced tumour growth or impaired killing of the tumour cells, there is evidence that high-dosage dexamethasone impairs the control of delayed nausea and emesis, whereas lower doses appear more beneficial. To come closer to the most adequate dose, we started a prospective, single-blind, randomized trial investigating additional dosage of 8 or 20 mg dexamethasone to tropisetron (Navoban), a 5-HT3 receptor antagonist, in cis-platinum-containing chemotherapy. After an interim analysis of 121 courses of chemotherapy in 69 patients, we have been unable to detect major differences between both treatment alternatives. High-dose dexamethasone (20 mg) had no advantage over medium-dose dexamethasone with respect to objective and subjective parameters of acute and delayed nausea and vomiting. In relation to concerns about the use of corticosteroids in non-haematological cancer chemotherapy, we suggest that 8 mg or its equivalent should be used in combination with 5-HT3 antagonists until further research proves otherwise.


Subject(s)
Antiemetics/administration & dosage , Dexamethasone/administration & dosage , Indoles/administration & dosage , Nausea/prevention & control , Serotonin Antagonists/administration & dosage , Vomiting, Anticipatory/prevention & control , Abdominal Neoplasms/drug therapy , Adult , Aged , Antineoplastic Agents/adverse effects , Carcinoma/drug therapy , Cisplatin/adverse effects , Dose-Response Relationship, Drug , Fallopian Tube Neoplasms/drug therapy , Female , Humans , Infusions, Intravenous , Male , Middle Aged , Nausea/chemically induced , Ovarian Neoplasms/drug therapy , Prospective Studies , Single-Blind Method , Tropisetron , Vomiting, Anticipatory/chemically induced
8.
Xenotransplantation ; 5(1): 93-8, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9507739

ABSTRACT

Previous studies have shown that CD4+ T cells are responsible for the great strength of cell-mediated xenograft rejection in the mouse. In vitro studies have suggested that this CD4+ response is to xenogeneic antigens that are presented indirectly. The present studies were carried out in order to determine whether the strength of cell-mediated xenograft rejection in vivo is dependent on the CD4+ indirect response. We grafted pig skin onto mice that express class II MHC antigens only on their thymic epithelial cells (II-4+ mice). These mice have normal numbers of functional peripheral CD4+ T cells; however they lack class II MHC expression on their antigen presenting cells and are thus incapable of mounting a CD4+ T cell-mediated indirect response. Xenograft survival was prolonged on these mice. Furthermore, administration of cyclosporine and anti-CD8 monoclonal antibodies to II-4+ recipients prolonged xenograft survival to at least the same extent as allograft survival, demonstrating that the strength of cell-mediated xenograft rejection resides in the CD4+ indirect response. Despite the increased survival time, xenograft rejection still occurred in the absence of the indirect pathway. Depletion of the II-4+ recipients of their CD4+ T cell population prolonged xenograft survival even further, suggesting the presence of a weaker CD4+ direct mechanism which was virtually undetectable in vitro.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Graft Rejection/etiology , Graft Rejection/immunology , Transplantation, Heterologous/adverse effects , Transplantation, Heterologous/immunology , Animals , Cyclosporine/pharmacology , Cytokines/biosynthesis , Graft Survival/immunology , Histocompatibility Antigens Class II/genetics , Histocompatibility Antigens Class II/metabolism , Immunity, Cellular , Immunosuppressive Agents/pharmacology , In Vitro Techniques , Mice , Mice, Inbred A , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Transgenic , Skin Transplantation/adverse effects , Skin Transplantation/immunology , Swine , Swine, Miniature
9.
J Nurs Adm ; 26(4): 33-8, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8774470

ABSTRACT

Role restructuring can be the key to maximizing efficiency, productivity, and operational effectiveness. The clinical nurse specialist role was restructured from a divisional project focus to a unit-based design to enhance the care of specific patient populations. The authors describe the process used to make this change, the outcomes achieved, and the lessons learned.


Subject(s)
Hospital Restructuring , Hospital Units/organization & administration , Job Description , Nurse Clinicians/organization & administration , Efficiency, Organizational , Humans , Organizational Innovation , Outcome and Process Assessment, Health Care , Workload
10.
Life Sci ; 56(23-24): 2065-72, 1995.
Article in English | MEDLINE | ID: mdl-7776833

ABSTRACT

Anandamide (arachidonoylethanolamide) was shown to inhibit macrophage-mediated killing of tumor necrosis factor-sensitive murine L929 fibroblasts. Scanning electron microscopy (SEM) demonstrated that L929 cells, co-cultured with Propionibacterium acnes (P. acnes)-activated peritoneal macrophages from mice treated with vehicle, were either disrupted or had surface abnormalities and numerous punctate lesions. In contrast, L929 cells co-cultured with macrophages from mice receiving P. acnes in concert with Anandamide (20 mg/kg-80 mg/kg) or the exogenous cannabinoid delta-9-tetrahydrocannabinol (THC; 80 mg/kg) did not exhibit ultrastructural abnormalities. Cytotoxicity assays were performed in parallel with SEM in order to determine whether ultrastructural observations correlated with target cell killing as measured by release of radiolabel from L929 target cells. P. acnes-activated macrophages from vehicle-treated mice elicited 41% specific release of radiolabel from [51Cr]-labeled L929 cells. In contrast, macrophages from animals treated with P. acnes and with 20, 40, or 80 mg/kg Anandamide exhibited 38%, 25%, or 28% specific release of radiolabel, respectively. Similarly, macrophages from animals treated with P. acnes and with 80 mg/kg THC exhibited 21% specific release of radiolabel. In vitro cytotoxicity studies using radiolabeled L929 target cells and conditioned medium from RAW264.7 murine macrophage-like cells allowed for determination of the time interval over which Anandamide exerted its inhibitory effect. Maximal inhibition of target cell killing occurred when conditioned medium was obtained from macrophages exposed to Anandamide for 1 hr prior to activation. In contrast, conditioned medium from THC-treated macrophages exerted its maximal inhibition of target cell killing when obtained from RAW264.7 cells pretreated for 24hr-48hr prior to activation. These results indicate that Anandamide and THC exert a similar inhibition of killing of TNF-sensitive target cells. However, the time interval over which these two substances elicit their suppressive effect differs.


Subject(s)
Arachidonic Acids/pharmacology , Cytotoxicity, Immunologic/drug effects , Macrophages, Peritoneal/drug effects , Tumor Necrosis Factor-alpha/metabolism , Animals , Cannabinoids/pharmacology , Cell Line , Endocannabinoids , Fibroblasts/drug effects , Fibroblasts/metabolism , Macrophages, Peritoneal/immunology , Macrophages, Peritoneal/ultrastructure , Mice , Microscopy, Electron, Scanning , Polyunsaturated Alkamides
11.
J Exp Med ; 179(5): 1645-52, 1994 May 01.
Article in English | MEDLINE | ID: mdl-8163942

ABSTRACT

When mice are lethally irradiated and reconstituted with allogeneic bone marrow cells, their skin is repopulated over a period of several months with Langerhans cells (LC) of marrow donor origin. Skin from such mice, when transplanted to unirradiated syngeneic recipients, became in many cases the sites of intense inflammatory responses that led to varying degrees of destruction of the transplanted skin and in some instances, to rejection of the entire graft. The frequency and intensity of these responses were influenced by the nature of the immunogenetic disparity between the donors and recipients of the marrow cells. Chimeric skin placed on hybrid mice derived from crosses between the marrow donors and recipients behaved in all respects as syngeneic grafts or autografts. When the recipients of the chimeric skin were presensitized to the antigens of the marrow donor, the responses were especially intense, and resulted in all cases in complete rejection. Thus the immunologically mediated attack on the allogeneic LCs was accompanied by widespread and nonspecific destruction of bystander cells. In all cases, the inflammation and tissue damage were confined sharply to the grafted skin, showing clearly that nonspecific or indirect tissue destruction is entirely consistent with highly selective destruction of grafted tissues. This finding removes a major objection to postulated mechanisms of rejection that involve indirect destruction of grafted tissues.


Subject(s)
Graft Rejection/immunology , Skin Transplantation/immunology , Animals , Bone Marrow/radiation effects , Bone Marrow Cells , Bone Marrow Transplantation , Chimera , Graft Rejection/pathology , Immunosuppression Therapy , Mice , Mice, Inbred C3H , Skin/cytology , Skin/immunology , Whole-Body Irradiation
12.
Life Sci ; 54(23): 1831-44, 1994.
Article in English | MEDLINE | ID: mdl-8196497

ABSTRACT

Macrophages have been shown to undergo a sequential process to full activation in response to priming and triggering signals such as gamma interferon (IFN gamma) and bacterial lipopolysaccharide (LPS). These cells also may be driven directly to full activation by exposure to relatively high concentrations of LPS. Each of the stages to activation is associated with differential protein expression suggesting that newly synthesized proteins are associated with the functional activities attributable to that activation state. These observations indicate that protein profiles may serve as a barometer of the macrophage activation state. Delta-9-tetrahydrocannabinol (THC), the major psychoactive component in marijuana, was shown to inhibit inducible protein expression in response to the priming agents Concanavalin A (Con A) supernatant and IFN gamma. THC also suppressed protein expression in response to LPS. P388D1 and RAW264.7 macrophage-like cells, treated with Con A supernatant or IFN gamma, exhibited restructuring of protein profiles based on iso-Dalt two-dimensional gel electrophoresis. Protein profile restructuring, distinctive from that elicited in response to priming agents, was seen for macrophages treated with LPS. Treatment of macrophages with Con A supernatant, IFN gamma, or LPS in concert with THC (10(-7) M to 10(-5) M), resulted in the generation of protein profiles whose patterns reverted approximately to those of unprimed or unactivated macrophages. THC was shown to alter the expression of select proteins whose induction is associated with macrophage priming or activation. The expression of P388D1 macrophage class II Ia molecules of the major histocompatibility complex (MHC), in response to Con A supernatant and IFN gamma, was inhibited. THC also altered the expression of tumor necrosis factor alpha (TNF alpha) elicited by RAW264.7 cells in response to LPS. These results suggest that THC alters macrophage functional activities, at least in part, by suppressing their capacity to express effector molecules elicited in response to priming and activating signals.


Subject(s)
Dronabinol/pharmacology , Macrophages/drug effects , Protein Biosynthesis , Animals , Cell Line , Concanavalin A/pharmacology , Lipopolysaccharides/pharmacology , Macrophages/metabolism , Mice , Mice, Inbred BALB C , Mice, Inbred DBA , Tumor Necrosis Factor-alpha/biosynthesis
13.
Nurs Clin North Am ; 28(4): 783-92, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8265418

ABSTRACT

Once a primary SCI occurs, there is great potential for further deterioration in spinal cord function due to secondary injury processes. Deterioration in the function of the spinal cord needs to be detected in a timely manner so that interventions to limit the progression of injury can be initiated. Spinal cord function assessment should be thorough, systematic, easy to perform, and based on spinal cord structure and function. Because sensory and motor information is carried in different tracts, with locations in different parts of the spinal cord, it is important to individually assess and document the function of each major tract. A spinal cord surveillance tool was developed that incorporated motor and sensory parameters by cord segment level. The aim of developing and implementing the flowsheet was to improve the quality of nursing care given to SCI patients by providing nurses with a tool that (1) standardizes the assessment, (2) facilitates comparison of findings to previous assessments, and (3) improves communication of patient status data among health care team members.


Subject(s)
Psychomotor Performance/physiology , Spinal Cord Injuries/nursing , Spinal Cord/physiopathology , Humans , Monitoring, Physiologic/methods , Monitoring, Physiologic/nursing , Nursing Records , Spinal Cord Injuries/physiopathology
14.
J Pharmacol Exp Ther ; 267(3): 1558-65, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8263818

ABSTRACT

Delta 9-tetrahydrocannabinol (delta 9-THC), the major psychoactive component of marijuana, has been shown to suppress macrophage soluble cytolytic activity. The purpose of this study was to determine whether delta 9-THC inhibited this function by affecting tumor necrosis factor-alpha (TNF-alpha). The RAW264.7 macrophage cell line was used as an in vitro bacterial lipopolysaccharide-inducible system for production of TNF-alpha. Macrophage-conditioned medium of RAW264.7 macrophages treated with delta 9-THC was shown to be deficient in tumoricidal activity. Immunoprecipitation experiments demonstrated that the macrophage-conditioned medium of cultures treated with drug contained lower levels of TNF-alpha. Northern analysis indicated that delta 9-THC had no effect on the levels of TNF-alpha messenger RNA. However, radiolabel pulsing and pulse-chase experiments revealed that the intracellular conversion of the 26-kD presecreted form of TNF-alpha to the 17-kD secreted form was inhibited by the drug. These results indicate that delta 9-THC suppresses soluble macrophage tumoricidal activity, at least in part, by decreasing the intracellular conversion of presecretory TNF-alpha to its 17-kD secretory form.


Subject(s)
Dronabinol/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Protein Processing, Post-Translational/drug effects , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Animals , Cell Line , Culture Media , Gene Expression/drug effects , Lipopolysaccharides , Macrophages/physiology , Mice , Models, Biological , RNA, Messenger/drug effects , RNA, Messenger/metabolism , Rabbits , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism
15.
Int J Immunopharmacol ; 15(3): 371-82, 1993 Apr.
Article in English | MEDLINE | ID: mdl-8389327

ABSTRACT

The effect of delta-9-tetrahydrocannabinol (delta-9-THC), the major psychoactive component of marijuana, on the capacity of Bacillus Calmétte-Guérin (BCG)-activated macrophages to lyse L929 tumor cells, Naegleria fowleri amoebae, and herpes simplex virus-infected cells was examined. Delta-9-THC inhibited tumoricidal and amoebicidal activity in a dose-related manner. Antiviral activity was decreased when mice received 25 and 50 mg/kg delta-9-THC. The cannabinoid did not directly suppress the activation of macrophages as determined by levels of 5'-nucleotidase activity and did not inhibit splenic T-lymphocytes of BCG-recipient mice from producing interferon gamma. Nomarski optics microscopy, scanning electron microscopy, and radiolabeling binding studies demonstrated that macrophages from delta-9-THC-treated mice retained their capacity to attach to their targets. These results suggest that delta-9-THC suppresses cell contact-dependent amoebicidal, tumoricidal, and antiviral activities of activated macrophages at a stage following effector cell-target cell conjugation.


Subject(s)
BCG Vaccine/immunology , Cell Communication , Cytotoxicity, Immunologic/drug effects , Dronabinol/pharmacology , Macrophages/drug effects , 5'-Nucleotidase/analysis , Animals , Cell Adhesion/drug effects , Female , Interferon-gamma/biosynthesis , Macrophage Activation/drug effects , Macrophages/immunology , Macrophages/metabolism , Mice
17.
Infect Immun ; 60(12): 5126-31, 1992 Dec.
Article in English | MEDLINE | ID: mdl-1452346

ABSTRACT

Mouse peritoneal macrophages activated by different immunomodulators (Mycobacterium bovis bacillus Calmette-Guérin or Propionibacterium acnes) destroy Naegleria fowleri amoebae by a contact-dependent process and by soluble cytolytic molecules secreted by macrophages in response to lipopolysaccharide. The goal of this study was to determine whether the arginine-dependent cytolytic mechanism which results in the production of nitric oxide from arginine by activated macrophages destroys the amoebae. Amoebicidal activity of activated macrophages was determined by coculturing macrophages with N. fowleri amoebae radiolabeled with 3H-uridine. The percent specific release of radiolabel was used as an index of cytolysis of the amoebae. The inhibitors NG-monomethyl-L-arginine and arginase were used to determine whether the arginine pathway was a major effector mechanism responsible for amoebicidal activity of activated macrophages. Both the arginine analog NG-monomethyl-L-arginine and arginase, which breaks down arginine, decreased macrophage amoebicidal activity. Addition of arginine to arginine-free medium restores amoebicidal activity to activated macrophage cultures. These results demonstrate that the arginine pathway is an important mechanism for the destruction of susceptible N. fowleri amoebae.


Subject(s)
Arginine/physiology , Cytotoxicity, Immunologic , Macrophages/immunology , Naegleria fowleri/immunology , Animals , Arginine/analogs & derivatives , Arginine/pharmacology , Female , Macrophage Activation , Mice , Mice, Inbred C3H , Mice, Inbred C57BL , Microscopy, Electron, Scanning , Nitric Oxide/metabolism , Tumor Necrosis Factor-alpha/physiology , omega-N-Methylarginine
18.
Proc Soc Exp Biol Med ; 200(3): 422-30, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1319584

ABSTRACT

The purpose of this study was to examine the effect of delta 9-tetrahydrocannabinol (delta 9-THC), the major psychoactive component of marijuana, on T lymphocyte functional competence against herpes simplex virus Type 1 (HSV1) infection. Spleen cells from C3H/HeJ (H-2k) mice primed with HSV1 and exposed to delta 9-THC were examined for anti-HSV1 cytolytic T lymphocyte (CTL) activity. Flow cytometry was used to determine whether delta 9-THC altered T cytotoxic (Lyt-2+) and T helper (L3T4+) lymphocyte numbers or cell ratios. Nomarski optics microscopy was used to determine whether effector lymphocytes from drug-treated mice were able to bind to virally infected L929 (H-2k) target cells. Cytotoxicity assays demonstrated that CTL from mice exposed to delta 9-THC were deficient in anti-HSV1 cytolytic activity. delta 9-THC in vivo treatment had little effect on the number of T lymphocytes expressing the Lyt-2 or L3T4 antigens. Nomarski optics microscopy revealed that the CTL from the drug-treated mice were able to bind specifically to the HSV1-infected targets. However, delta 9-THC in vivo exposure affected CTL cytoplasmic polarization toward the virus-infected target cell. CTL granule reorientation toward the effector cell-target cell interface following cell conjugation occurred at a lower frequency in co-cultures containing CTL from drug-treated mice. These results suggest that delta 9-THC elicits dysfunction in CTL by altering effector cell-target cell postconjugation events.


Subject(s)
Dronabinol/pharmacology , Simplexvirus/immunology , T-Lymphocytes, Cytotoxic/immunology , Animals , Cytotoxicity Tests, Immunologic , Female , Leukocyte Count , Mice , Mice, Inbred C3H , Microscopy , Microscopy, Fluorescence , Spleen/drug effects , Spleen/microbiology , T-Lymphocytes, Cytotoxic/drug effects , T-Lymphocytes, Helper-Inducer/drug effects
19.
J Protozool ; 39(1): 235-41, 1992.
Article in English | MEDLINE | ID: mdl-1560419

ABSTRACT

Macrophage-conditioned medium (M phi CM) prepared from mouse peritoneal macrophages activated in vivo with bacillus Calmette-Guérin (BCG) or Propionibacterium acnes and triggered with lipopolysaccharide in vitro contained tumoricidal and amoebicidal activity. The murine fibroblast cell line L929 was used as the indicator of tumoricidal activity and Naegleria fowleri amoeba was used to detect amoebicidal activity in M phi CM. The protease inhibitor, soybean trypsin inhibitor, decreased tumoricidal activity but had little effect on amoebicidal activity in M phi CM. Anti-TNF alpha antiserum inhibited tumoricidal activity in M phi CM. The antiserum reduced amoebicidal activity in BCG-activated M phi CM but had no effect on amoebicidal activity in P. acnes-activated M phi CM. Recombinant TNF alpha, rIL-1 alpha, or rIL-1 beta independently did not affect cytolysis of amoebae. Also, rTNF alpha had no effect on the growth of amoebae. Preparative flat-bed electrofocusing of BCG-activated M phi CM yielded fractions that exhibited different amoebicidal and tumoricidal activity profiles. Three domains of activity were analyzed (acidic, neutral, and basic). Anti-TNF alpha antiserum eliminated tumoricidal activity, but not amoebicidal activity, in fractions from the acidic domain. A combination of anti-TNF alpha and anti-IL-1 alpha antisera failed to eliminate amoebicidal activity in fractions from the basic domain. These results indicate that different factors are responsible for macrophage amoebicidal and tumoricidal activity. The amoebicidal factors in M phi CM affected cytolysis of several species of amoebae.


Subject(s)
Macrophage Activation , Macrophages/immunology , Naegleria fowleri/immunology , Tumor Cells, Cultured/immunology , Animals , Endopeptidases/metabolism , Female , Interleukin-1/physiology , Isoelectric Focusing , Mice , Mice, Inbred C3H , Mice, Inbred C57BL , Protease Inhibitors/pharmacology , Recombinant Proteins , Tumor Necrosis Factor-alpha/physiology
20.
J Protozool ; 37(3): 168-73, 1990.
Article in English | MEDLINE | ID: mdl-2359044

ABSTRACT

The present study was undertaken to determine whether murine macrophage cell lines exhibited in vitro amoebicidal activity comparable to that elicited by activated murine peritoneal macrophages. Peritoneal macrophages activated in vivo by bacillus Calmette-Guérin or Propionibacterium acnes demonstrated significant cytolysis of Naegleria fowleri amoebae. The macrophage cell line RAW264.7 also effected cytolysis of amoebae, but to a lesser extent than that elicited by activated peritoneal macrophages. However, the macrophage cell lines, J774A.1 and P388D1, did not exhibit amoebicidal activity. Macrophage conditioned medium prepared from RAW264.7 macrophages mediated cytolysis of L929 tumor cells but had no effect on N. fowleri amoebae. In addition, neither recombinant tumor necrosis factor nor recombinant interleukin-1 exhibited amoebicidal activity. Scanning electron microscopy of co-cultures revealed that N. fowleri bound to activated peritoneal macrophages and RAW264.7 macrophages. These results suggest that RAW264.7 macrophages treated in vitro with lipopolysaccharide are similar to macrophages activated in vivo in that they effect contact-dependent cytolysis of Naegleria fowleri amoebae. The RAW264.7 macrophages are unlike primary macrophage cultures in that they either do not release soluble amoebicidal factors into the conditioned medium or they release insufficient quantities.


Subject(s)
Cytotoxicity, Immunologic , Macrophages/immunology , Naegleria/immunology , Animals , Antibodies, Protozoan/biosynthesis , Biological Factors/immunology , Cell Line , Macrophages/ultrastructure , Mice , Mice, Inbred C57BL , Microscopy, Electron, Scanning , Naegleria/ultrastructure , Neoplasms/immunology , Peritoneal Cavity/cytology , Tumor Cells, Cultured
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