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1.
Trauma Case Rep ; 30: 100373, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33299923

ABSTRACT

Cardiac injury secondary to non-penetrating trauma is more common than thought, albeit, the injury is usually minor and goes undiagnosed without significant sequelae in most cases. Blunt cardiac rupture is much rarer accounting for <0.05% of all trauma cases but lethal in most circumstances. We present a case report of a young trauma victim who presented with both right atrial rupture and traumatic atrial septal disruption (ASD) requiring extra-corporeal life support (ECLS) and surgical repair. Blunt cardiac trauma with chamber rupture and septal disruption is a devastating injury. Stopping the hemorrhage and using ECLS gave our patient time to stabilize before definitive management of her traumatic ASD.

2.
NPJ Vaccines ; 2: 1, 2017.
Article in English | MEDLINE | ID: mdl-29263862

ABSTRACT

There are over 6 billion vaccine doses administered each year, most containing aluminium-based adjuvants, yet we still do not have a complete understanding of their mechanisms of action. Recent evidence has identified host DNA and downstream sensing as playing a significant role in aluminium adjuvant (aluminium hydroxide) activity. However, the cellular source of this DNA, how it is sensed by the immune system and the consequences of this for vaccination remains unclear. Here we show that the very early injection site reaction is characterised by inflammatory chemokine production and neutrophil recruitment. Intravital imaging demonstrates that the Alum injection site is a focus of neutrophil swarms and extracellular DNA strands. These strands were confirmed as neutrophil extracellular traps due to their sensitivity to DNAse and absence in mice deficient in peptidylarginine deiminase 4. Further studies in PAD4-/- mice confirmed a significant role for neutrophil extracellular trap formation in the adjuvant activity of Alum. By revealing neutrophils recruited to the site of Alum injection as a source of the DNA that is detected by the immune system this study provides the missing link between Alum injection and the activation of DNA sensors that enhance adjuvant activity, elucidating a key mechanism of action for this important vaccine component.

3.
Pregnancy Hypertens ; 2(3): 262-3, 2012 Jul.
Article in English | MEDLINE | ID: mdl-26105361

ABSTRACT

INTRODUCTION: Combining HELLP syndrome patient groups in publications and presentations may obfuscate any potential differences among patient groups with regard to maternal-perinatal outcomes and rendered therapies. OBJECTIVES: We explored the prevalence of major maternal morbidity (MMM) for patients with severe preeclampsia (SPRE) and each defined group of HELLP syndrome. METHODS: Retrospective cohort study 2000-2007 of patients categorized either as class 1 HELLP syndrome (HELLP1, platelets⩽50,000, AST⩽70,LDH⩽600), class 2 (HELLP2, platelets>50,000 to ⩽100,000), class 3 (HELLP3, platelets>100,000 to ⩽150,000), or partial/incomplete (HELLP4) with only 2 of 3 diagnostic parameters present. All SPRE patients (no HELLP) of 2005-2007 were also evaluated. Total MMM for each group was determined. MMM included cardiopulmonary [cardiogenic or noncardiogenic pulmonary edema, pleural or pericardial effusion, pulmonary embolus, indicated intubation, myocardial infarction or arrest], hematologic/coagulation [DIC, transfused blood products], central nervous system/visual [stroke, cerebral edema, hypertensive encephalopathy, vision loss], hepatic [subcapsular hematoma or rupture] or renal complications [acute tubular necrosis or renal failure]. All HELLP1 and HELLP2 patients received corticosteroids, magnesium sulfate and anti-hypertensives. Comparison among groups was done using Chi-square or Fisher exact test at 95% CI. RESULTS: Four hundred and twenty patients had a form of HELLP syndrome 2000-2007; 688 patients had SPRE 2005-2007.The prevalence of MMM for each patient group was determined: HELLP1=41.5%; HELLP2=10.3%; HELLP3=20.0%; HELLP4=21.0%; and SPRE=17.7%. MMM in HELLP1 was significantly increased over all other groups (P<0.001). Combining MMM for HELLP1+HELLP2 produced a prevalence of 22.1% MMM, insignificantly different from all others including HELLP3, HELLP4 and SPRE (p=0.19), thereby obscuring the significantly elevated MMM of HELLP1 patients. CONCLUSION: Only patients with HELLP1 have significantly increased MMM compared to other HELLP groups or SPRE. Failing to separately evaluate patients with HELLP1 in studies of HELLP syndrome could lead to mistaken conclusions about the effectiveness of a treatment to reduce MMM. All publications reviewing HELLP syndrome management should address how well it functions to reduce patient development of HELLP1 and thus minimize MMM.

4.
Pregnancy Hypertens ; 2(3): 314, 2012 Jul.
Article in English | MEDLINE | ID: mdl-26105459

ABSTRACT

INTRODUCTION: Posterior reversible encephalopathy syndrome (PRES) has been reported to occur in patients with eclampsia. In both conditions there is evidence to suggest disordered cerebral autoregulation. OBJECTIVES: We sought to investigate the concurrence of PRES with eclampsia and to describe the associated obstetric, radiologic and critical care correlates. METHODS: Single center 2001-2010 retrospective cohort study of all patients with eclampsia who underwent neuroimaging via magnetic resonance imaging (MRI) or computerized tomography (CT) with or without contrast. The medical records of all patients with eclampsia during the study interval were identified, evaluated and extracted for pertinent data; a diagnosis of PRES was made by radiologists using standard criteria. RESULTS: Forty-six of forty-seven (97.9%) patients with eclampsia revealed PRES on neuroimaging using one or more modalities: MRI without contrast=41 (87.2%), MRI with contrast=27 (57.4%), CT without contrast=16 (34%), CT with contrast=7 (14.8%) and/or MRA/MRV=2 (4.3%). PRES was identified within the parietal (36, 78.3%), occipital (35, 76.1%), frontal (29, 63%), temporal (13, 28.3%) and basal ganglia/ brainstem/cerebellum (12, 26.1%). Eclampsia occurred antepartum in 23 patients, postpartum in 24 patients with 22 vaginal/25 cesarean deliveries at a mean maternal age of 21.8 years (range 15-39) and a mean gestational age of 33.9 weeks (range 22.4-41.7 weeks). Ethnicity was African-American in 38 patients. Headache was the most common presenting symptom (87.2%) followed by altered mental status (51.1%), visual disturbances (34%) and nausea/vomiting (19.1%). Severe systolic hypertension was present in 22 (47%) of patients.Use of antihypertensives (87%), magnesium sulfate (100%), diuretics (66%) and corticosteroids (50%) facilitated maternal recovery in all cases with usually a brief hospitalization (mean 3.9 days, range 1-20 days). CONCLUSION: The common finding of PRES in patients with eclampsia suggests that PRES may be part of the pathogenesis of eclampsia. We speculate that therapy targeted at prevention or reversal of PRES pathogenesis will prevent or facilitate recovery from eclampsia.

5.
J Dent Res ; 90(10): 1221-7, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21690565

ABSTRACT

Despite existing preventive and therapeutic measures, caries remains a ubiquitous infectious disease. Vaccine studies suggest that an adaptive immune response, culminating in effective antibody production, may reduce an individual's susceptibility to caries. However, the efficacy of the immune response elicited by mutans streptococci in the oral cavity remains controversial. A greater understanding of the early stages of the adaptive immune response to cariogenic bacteria may potentially assist therapeutic targeting and design. We therefore sought to characterize dendritic cell (DC) activation and antigen presentation following Streptococcus mutans exposure. We found that S. mutans up-regulated DC expression of co-stimulatory molecules and MHCII in vitro and that DCs effectively processed and presented exogenously administered antigen. These DCs effectively initiated T-cell proliferation, but this was abrogated by live bacteria. The in vitro DC activation effects were not mirrored in vivo, where DCs in draining lymph nodes did not mature following oral exposure to S. mutans. Analysis of these data provides a model for studying antigen uptake from the oral cavity and evidence that, in vitro, S. mutans activates dendritic cells, a critical event for initiating adaptive immunity.


Subject(s)
Antigen Presentation/immunology , Dendritic Cells/immunology , Dendritic Cells/microbiology , Dental Caries Susceptibility , Streptococcus mutans/immunology , Animals , Bone Marrow Cells/immunology , Bone Marrow Cells/microbiology , Cells, Cultured , Coculture Techniques , Female , Flow Cytometry , Genes, MHC Class II/immunology , Lymphocyte Activation , Mice , Mice, Inbred C57BL , Mice, Transgenic , T-Lymphocytes/immunology
6.
FEBS Lett ; 585(23): 3640-8, 2011 Dec 01.
Article in English | MEDLINE | ID: mdl-21570969

ABSTRACT

Despite the profound impact of biologics on the treatment of rheumatoid arthritis (RA), long lasting disease remission remains elusive. We propose that this is a consequence of failing to target the right molecular pathway in the most relevant patient group at the appropriate time and place in disease progression. A limitation to testing this approach is the availability of disease models representing the discrete steps in autoimmune pathogenesis. A particular example is the paucity of models to dissect the conditions permissive for the breach of self-tolerance, which would subsequently allow identification and testing of therapeutics for re-establishment of self-tolerance. We conclude that a detailed understanding of the location and timing of events leading to the systemic breach of self-tolerance and subsequent progression to tissue specific pathology are required if rational application of existing drugs and identification of novel targets is to be achieved. This will take the personalised medicine revolution into the realms of contextualised medicine, whereby the right drug is targeted to the right tissue, in the right patient, at the right time.


Subject(s)
Arthritis/immunology , Animals , Arthritis/pathology , Autoimmunity/immunology , Humans , Immune Tolerance/immunology , Joints/immunology , Joints/pathology , Models, Biological , Time Factors
7.
Br J Pharmacol ; 159(4): 808-11, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20015295

ABSTRACT

BACKGROUND AND PURPOSE: T-cells may play a role in the evolution of ischaemic damage and repair, but the ability to image these cells in the living brain after a stroke has been limited. We aim to extend the technique of real-time in situ brain imaging of T-cells, previously shown in models of immunological diseases, to models of experimental stroke. EXPERIMENTAL APPROACH: Male C57BL6 mice (6-8 weeks) (n= 3) received a total of 2-5 x 10(6) carboxyfluorescein diacetate succinimidyl ester (CFSE)-labelled lymphocytes from donor C57BL6 mice via i.v. injection by adoptive transfer. Twenty-four hours later, recipient mice underwent permanent left distal middle cerebral artery occlusion (MCAO) by electrocoagulation or by sham surgery under isoflurane anaesthesia. Female hCD2-green fluorescent protein (GFP) transgenic mice that exhibit GFP-labelled T-cells underwent MCAO. At 24 or 48 h post-MCAO, a sagittal brain slice (1500 microm thick) containing cortical branches of the occluded middle cerebral artery (MCA) was dissected and used for multiphoton laser scanning microscopy (MPLSM). KEY RESULTS: Our results provide direct observations for the first time of dynamic T-cell behaviour in living brain tissue in real time and herein proved the feasibility of MPLSM for ex vivo live imaging of immune response after experimental stroke. CONCLUSIONS AND IMPLICATIONS: It is hoped that these advances in the imaging of immune cells will provide information that can be harnessed to a therapeutic advantage.


Subject(s)
Brain/metabolism , Infarction, Middle Cerebral Artery/metabolism , Microscopy, Fluorescence, Multiphoton , Molecular Imaging , Molecular Probe Techniques , T-Lymphocytes/metabolism , Adoptive Transfer , Animals , Brain/immunology , Disease Models, Animal , Feasibility Studies , Female , Fluoresceins/metabolism , Fluorescent Dyes/metabolism , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Infarction, Middle Cerebral Artery/immunology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Succinimides/metabolism , T-Lymphocytes/immunology , T-Lymphocytes/transplantation , Time Factors
8.
Parasite Immunol ; 31(3): 147-50, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19222786

ABSTRACT

T-cells are known to play a role in the pathology associated with experimental cerebral malaria, although it has not previously been possible to examine their behaviour in brain. Using multiphoton laser scanning microscopy, we have examined the migration and movement of these cells in brain tissue. We believe that this approach will help define host-parasite interactions and examine how intervening in these relationships affects the development of cerebral pathology.


Subject(s)
Brain/immunology , Brain/pathology , Cell Movement/immunology , Malaria, Cerebral/immunology , Malaria, Cerebral/pathology , Microscopy, Confocal/methods , T-Lymphocytes/immunology , Animals , Mice
9.
Work ; 34(4): 455-64, 2009.
Article in English | MEDLINE | ID: mdl-20075523

ABSTRACT

Musculoskeletal pain in school-aged children is highly prevalent. While there are many potential factors relating to this discomfort, one unexplored factor is the ergonomic mismatch. The objective of this study was to determine whether the degree of mismatch between the body dimensions and the classroom furniture was associated with body discomfort. One hundred and thirty-nine children in a Midwestern U.S. school district participated in the study where demographic information, anthropometric measurements, self-reported regional body discomfort, and furniture measurements were collected. The results indicate an extremely high prevalence of ergonomic mismatch. Contrary to what was hypothesized, the ergonomic mismatch was not associated with body discomfort. The lack of association may have been a result of the extremely high prevalence of ergonomic mismatch as well as potential adaptations by the students. Although almost every student was found to not fit their desk and chairs, ergonomic mismatch had limited impact on the body discomfort. It appears that other factors such as backpack weight and time carrying may contribute more to the discomfort of students. However, caution is stress with regard to dismissing ergonomic mismatch factor as a potential risk factor since the extremely high prevalence may have washed out any effect.


Subject(s)
Ergonomics , Interior Design and Furnishings , Pain/etiology , Schools , Adolescent , Child , Female , Health Surveys , Humans , Male , Musculoskeletal Diseases/epidemiology , Ohio/epidemiology , Pain/epidemiology
10.
Ann Rheum Dis ; 68(6): 1059-66, 2009 Jun.
Article in English | MEDLINE | ID: mdl-18635595

ABSTRACT

BACKGROUND: The relative roles of innate immunity and antigen-specific T cells in rheumatoid arthritis remain controversial. Previous studies demonstrated that T-helper type 1 cells of irrelevant antigen specificity (ovalbumin) induced a transient arthritis in BALB/c mice, which recapitulates many of the pre-articular and articular features of human disease and is associated with the emergence of autoreactive T and B-cell responses to joint-specific antigens. However, the mechanisms underlying this phenomenon were unclear. OBJECTIVES: The aim of this study was to dissect the relative contribution of innate and heterologous antigen-specific pathways to the breach of self-tolerance and pathology observed in this model and how this may result from modified T and B-cell interactions. METHODS: To address this issue, experimental arthritis was elicited either by a non-specific inflammatory stimulus alone, by activation of T cells of an irrelevant specificity or a combination of both. RESULTS: The non-specific inflammatory response generated by lipopolysaccharide led to articular inflammation and cartilage erosion, but did not break tolerance to joint-specific antigens. In contrast, local activation of T cells of an irrelevant specificity produced a similar pathological picture but, in addition, induced T-cell responses to unrelated joint-specific antigens with associated activation of autoreactive B cells. These effects could be further potentiated by the addition of lipopolysaccharide. CONCLUSION: These data demonstrate that non-specific inflammation alone is insufficient to breach self-tolerance. In contrast, T cells of an irrelevant specificity, when triggered locally in an antigen-specific manner, can breach self-tolerance leading to arthritis and autoantibody production, which can then be amplified in a non-specific manner.


Subject(s)
Arthritis, Rheumatoid/immunology , Adoptive Transfer/methods , Animals , Antibody Formation , Arthritis, Experimental/immunology , Autoantigens/immunology , Autoimmunity/immunology , B-Lymphocytes/immunology , Cell Proliferation , Enzyme-Linked Immunosorbent Assay/methods , Female , Flow Cytometry , Fluorescent Antibody Technique, Indirect , Immunohistochemistry , Lipopolysaccharides/pharmacology , Lymphocyte Activation/immunology , Mice , Mice, Inbred BALB C , Self Tolerance/immunology , Th1 Cells/immunology , Th2 Cells/immunology
11.
Clin Exp Immunol ; 155(1): 107-16, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19076834

ABSTRACT

It is widely accepted that allergic asthma is orchestrated by T helper type 2 lymphocytes specific for inhaled allergen. However, it remains unclear where and when T cell activation and division occurs after allergen challenge, and whether these factors have a significant impact on airways inflammation. We therefore employed a CD4-T cell receptor transgenic adoptive transfer model in conjunction with laser scanning cytometry to characterize the location and timing of T cell division in asthma in vivo. Thus, for the first time we have directly assessed the division of antigen-specific T cells in situ. We found that accumulation of divided antigen-specific T cells in the lungs appeared to occur in two waves. The first very early wave was apparent before dividing T cells could be detected in the lymph node (LN) and coincided with neutrophil influx. The second wave of divided T cells accumulating in lung followed the appearance of these cells in LN and coincided with peak eosinophilia. Furthermore, accumulation of antigen-specific T cells in the draining LN and lung tissue, together with accompanying pathology, was reduced by intervention with the sphingosine 1-phosphate receptor agonist FTY720 2 days after challenge. These findings provide greater insight into the timing and location of antigen-specific T cell division in airways inflammation, indicate that distinct phases and locations of antigen presentation may be associated with different aspects of pathology and that therapeutics targeted against leukocyte migration may be useful in these conditions.


Subject(s)
Allergens/administration & dosage , Asthma/immunology , Lung/immunology , Lymph Nodes/immunology , Th2 Cells/immunology , Adoptive Transfer , Animals , Bronchoalveolar Lavage Fluid/immunology , Cell Division , Cell Movement/drug effects , Cytokines/immunology , Eosinophilia , Female , Fingolimod Hydrochloride , Flow Cytometry/methods , Humans , Immunosuppressive Agents/pharmacology , Mice , Mice, Inbred BALB C , Mice, Transgenic , Microscopy, Confocal , Models, Animal , Ovalbumin , Propylene Glycols/pharmacology , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/immunology , Sphingosine/analogs & derivatives , Sphingosine/pharmacology , Time Factors
12.
Parasite Immunol ; 30(4): 223-33, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18324925

ABSTRACT

Malaria infects 500 million people and kills an estimated 2.7 million annually, representing one of the most significant diseases in the world. However, efforts to develop effective vaccines have met with limited success. One reason is our lack of basic knowledge of how and where the immune system responds to parasite antigens. This is important as the early events during induction of an immune response influence the acquisition of effector function and development of memory responses. Our knowledge of the interactions of Plasmodia with the host immune system has largely been derived through in vitro study. This is a significant issue as the component parts of the immune system do not work in isolation and their interactions occur in distinct and specialized micro- and macro-anatomical locations that can only be assessed in the physiological context, in vivo. In this context, the availability of transgenic malaria parasites over the last 10 years has greatly enhanced our ability to understand and evaluate factors involved in host-parasite interactions in vivo. In this article, we review the current status of this area and speculate on what parasite transgenesis approaches will tell us about the development of Plasmodium-specific immune responses in the future.


Subject(s)
Animals, Genetically Modified/immunology , Host-Parasite Interactions/genetics , Host-Parasite Interactions/immunology , Plasmodium/genetics , Plasmodium/immunology , Animals , Humans , Malaria/immunology
13.
Clin Exp Immunol ; 151(1): 114-22, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17931392

ABSTRACT

Asthma is a heterogeneous disease that has been increasing in incidence throughout western societies and cytokines, including proinflammatory tumour necrosis factor alpha (TNF-alpha), have been implicated in the pathogenesis of asthma. Anti-TNF-alpha therapies have been established successfully in the clinic for diseases such as rheumatoid arthritis and Crohn's disease. TNF-alpha-blocking strategies are now being trialled in asthma; however, their mode of action is poorly understood. Based on the observation that TNF-alpha induces lymph node hypertrophy we have attempted to investigate this as a mechanism of action of TNF-alpha in airway inflammation by employing two models of murine airway inflammation, that we have termed short and long models, representing severe and mild/moderate asthma, respectively. The models differ by their immunization schedules. In the short model, characterized by eosinophilic and neutrophilic airway inflammation the effect of TNF-alpha blockade was a reduction in draining lymph node (DLN) hypertrophy, eosinophilia, interleukin (IL)-5 production and immunoglobulin E (IgE) production. In the long model, characterized by eosinophilic inflammation, TNF-alpha blockade produced a reduction in DLN hypertrophy and IL-5 production but had limited effects on eosinophilia and IgE production. These results indicate that anti-TNF-alpha can suppress DLN hypertrophy and decrease airway inflammation. Further investigations showed that anti-TNF-alpha-induced inhibition of DLN hypertrophy cannot be explained by preventing l-selectin-dependent capture of lymphocytes into the DLN. Given that overall TNF blockade was able to suppress the short model (severe) more effectively than the long model (mild/moderate), the results suggest that TNF-alpha blocking therapies may be more effective in the treatment of severe asthma.


Subject(s)
Asthma/immunology , Cytokines/immunology , Immunoglobulin G/therapeutic use , Lung/immunology , Receptors, Tumor Necrosis Factor/therapeutic use , T-Lymphocytes/immunology , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adoptive Transfer/methods , Animals , Asthma/pathology , Bronchial Hyperreactivity/immunology , Eosinophilia , Etanercept , Flow Cytometry , Hypertrophy , Lung/pathology , Lymph Nodes/immunology , Lymph Nodes/pathology , Mice , Mice, Inbred BALB C , Models, Animal , Ovalbumin , Time
14.
Inflamm Res ; 56(10): 391-401, 2007 Oct.
Article in English | MEDLINE | ID: mdl-18026695

ABSTRACT

The induction of an adaptive immune response is an essential step in the generation of long-lasting, protective immunity to pathogens. Many studies over the last few decades have identified the cell populations involved in the generation of antigen-specific immunity and elucidated the role of many important molecules. However, because of the low precursor frequency of antigen-specific cells, the immune system must be highly dynamic, surveying most sites of the body. Recent studies have, therefore, begun to examine how the cells of the immune system interact in vivo during the induction of an immune response, identifying new and important roles for certain molecules and revealing how previously unrecognised alterations in cell-cell interactions can have significant implications for the resulting immune response. Here we review some of these recent studies that provide a valuable insight into the mechanisms involved in the induction of immunity.


Subject(s)
Lymphocytes/physiology , Lymphoid Tissue/immunology , Animals , Antigen Presentation , Antigen-Presenting Cells/physiology , Cell Communication , Cell Movement , Humans , Luminescent Measurements , Lymph Nodes/immunology , Lymphocyte Activation , Magnetic Resonance Imaging , Microscopy , Signal Transduction , Spleen/immunology
15.
Histopathology ; 45(1): 82-6, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15228447

ABSTRACT

AIMS: To present four cases in which the clinical and endoscopic findings were consistent with microscopic colitis, but the inflammatory infiltrate included a conspicuous granulomatous reaction. Microscopic colitis is defined as a syndrome of chronic watery diarrhoea with a chronic inflammatory cell infiltrate in the colonic mucosa and without significant abnormalities at colonoscopy. It encompasses both collagenous and lymphocytic colitis. METHODS AND RESULTS: In all cases the clinical course and endoscopic findings were unlike Crohn's disease and no infectious agents were identified. In all cases the main symptom was frequent watery diarrhoea, all were female and there were no endoscopic findings apart from mild mucosal erythema. Histologically, an active chronic inflammatory infiltrate was accompanied by scattered non-necrotizing granulomas, often closely associated with crypt epithelium (cryptolytic or pericryptal granulomas). In three of the patients the symptoms began after antibiotic use or had worsened with antibiotic use. Two of the patients were on allopurinol at the time of the onset of symptoms. In two of the patients symptoms have continued for more than 10 years. One patient died as a result of medical complications relating to severe diarrhoea and dehydration. CONCLUSIONS: Microscopic colitis rarely may be characterized by granulomatous inflammation. Such patients should not be regarded as having Crohn's disease.


Subject(s)
Colitis, Microscopic/pathology , Granuloma/pathology , Adult , Aged , Colon/pathology , Fatal Outcome , Female , Humans , Inflammation/pathology , Middle Aged
16.
Neurosci Lett ; 314(3): 119-22, 2001 Nov 16.
Article in English | MEDLINE | ID: mdl-11704298

ABSTRACT

The mammalian suprachiasmatic nucleus (SCN) contains the main circadian clock. Neuropeptide Y (NPY) that is released from the intergeniculate leaflet of the lateral geniculate body to the SCN, acts in the SCN to advance circadian phase in the subjective day via the NPY Y2 receptor. We used semi-quantitative in situ hybridization to determine the effect of NPY on circadian clock genes, Period 1 (Per1) and Period 2 (Per2), expression in SCN slices. Addition of NPY to the brain slices in the subjective day resulted in reduction of Per1 and Per2 mRNA levels 0.5 and 2 h after treatment. NPY Y1/Y5 and Y2 agonists decreased Per1 within 0.5 h. These results suggest that NPY may induce phase shifts by mechanisms involving or resulting in reduction of Per1 and Per2 mRNA levels.


Subject(s)
Circadian Rhythm/physiology , Neurons/metabolism , Neuropeptide Y/analogs & derivatives , Neuropeptide Y/metabolism , Nuclear Proteins/genetics , RNA, Messenger/metabolism , Suprachiasmatic Nucleus/metabolism , Animals , Biological Clocks/drug effects , Biological Clocks/physiology , Cell Cycle Proteins , Circadian Rhythm/drug effects , Cricetinae , Gene Expression Regulation/drug effects , Gene Expression Regulation/physiology , In Situ Hybridization , Male , Mesocricetus , Neurons/drug effects , Neuropeptide Y/pharmacology , Peptide Fragments/pharmacology , Period Circadian Proteins , RNA, Messenger/drug effects , Receptors, Neuropeptide Y/drug effects , Receptors, Neuropeptide Y/metabolism , Suprachiasmatic Nucleus/cytology , Suprachiasmatic Nucleus/drug effects , Time Factors , Transcription Factors
17.
J Chromatogr A ; 919(1): 59-65, 2001 Jun 01.
Article in English | MEDLINE | ID: mdl-11459312

ABSTRACT

The use of on-line dialysis as a sample preparation technique for ion chromatography is described. A fully automated sample preparation device coupled to an ion chromatographic system for the determination of anions and cations in various matrices is presented. The method was based on stopped-flow dialysis, where the samples were continuously dialyzed for 10 min while the acceptor solution was stationary within the recipient channel. The matrices examined, without additional sample treatment, included milk, untreated wastewater, fruit juice, engine coolant, and a multivitamin tablet. The analyte recoveries for anions and cations in various matrices ranged from 87 to 106%. In addition, multiple sample injections were performed and repeatabilities were found in the range of 0.2 to 4%.


Subject(s)
Chromatography, Liquid/methods , Dialysis/methods , Anions/analysis , Cations/analysis , Reproducibility of Results
18.
Exp Biol Med (Maywood) ; 226(6): 559-64, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11395926

ABSTRACT

Liposomes prepared from naturally occurring biodegradable and nontoxic lipids are good candidates for local delivery of therapeutic agents. Treatment of arthritis by intra-articular administration of anti-inflammatory drugs encapsulated in liposomes prolongs the residence time of the drug in the joint. We have previously shown that intra-articular injection of human lactoferrin (hLf), a glycoprotein that possesses anti-inflammatory and antimicrobial activities, into mice with collagen-induced arthritis reduces inflammation. We have now investigated the possibility of using liposome-entrapped hLf as a delivery system to prolong hLf retention at sites of local inflammation such as the rheumatoid joint. Entrapment of hLf in negatively charged liposomes enhanced its accumulation in cultured human synovial fibroblasts from rheumatoid arthritis (RA) patients, compared with positively charged formulations or free protein. However, in the presence of synovial fluid, positively charged liposomes with entrapped hLf were more stable than the negatively charged formulations. In vivo experiments in mice with collagen-induced arthritis showed that the positive liposomes were more efficient in prolonging the residence time of hLf in the inflamed joint as compared with other liposomes. Thus, the amount of hLf retained in the joint after 2 hr was 60% of the injected dose in the case of positive liposomes and only 16% for negative pH-sensitive liposomes. The results suggest that entrapment of hLf in positively charged liposomes may modify its pharmacodynamic profile and be of therapeutic benefit in the treatment of RA and other local inflammatory conditions.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Arthritis, Rheumatoid/drug therapy , Drug Delivery Systems , Lactoferrin/administration & dosage , Animals , Anti-Inflammatory Agents, Non-Steroidal/metabolism , Arthritis, Rheumatoid/metabolism , Cells, Cultured , Collagen/adverse effects , Drug Stability , Electrochemistry , Fibroblasts/metabolism , Humans , Injections , Lactoferrin/chemistry , Lactoferrin/metabolism , Liposomes , Male , Mice , Synovial Fluid/metabolism , Synovial Membrane/cytology , Synovial Membrane/metabolism , Tissue Distribution
19.
Vaccine ; 19(20-22): 2965-74, 2001 Apr 06.
Article in English | MEDLINE | ID: mdl-11282208

ABSTRACT

The ability of non-ionic surfactant vesicles to induce systemic immune responses in mice following oral immunisation was studied using a standard antigen (bovine serum albumin), a synthetic measles peptide and an influenza sub-unit vaccine. The effectiveness of this formulation was significantly increased by incorporating bile salts (in particular deoxycholate) into the formulation. We have named the resulting vesicles bilosomes. We found that the most effective immunisation protocol was to give two doses of vaccine three days apart and then repeat this protocol two weeks later. Following this method, preparation of measles peptide in bilosomes produced a specific cell mediated response, as measured by splenocyte proliferation and IL-2 production. Of particular significance, these studies demonstrate that oral administration of bilosomes incorporating the influenza sub-unit vaccine could induce as potent an antibody response as the parenterally administered vaccine containing the same quantity of antigen. In addition, the Th1/Th2 balance, as measured by antibody subclasses, was similar whether animals were immunised by the oral or the parenteral vaccine route. As bilosomes are prepared from naturally occurring lipids and have no apparent toxicity associated with their use, they represent a useful modification of conventional lipid vesicle based systems for the oral delivery of proteins and peptides.


Subject(s)
Antigens/administration & dosage , Bile Acids and Salts/administration & dosage , Lipids/administration & dosage , Administration, Oral , Amino Acid Sequence , Animals , Antibody Formation , Antigens/immunology , Chemistry, Pharmaceutical , Humans , Immunization , Immunoglobulin G/blood , Immunoglobulin G/classification , Interleukin-10/biosynthesis , Interleukin-2/biosynthesis , Lymphocyte Activation , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Serum Albumin, Bovine/immunology
20.
Int J Biol Macromol ; 28(3): 213-8, 2001 Mar 14.
Article in English | MEDLINE | ID: mdl-11251228

ABSTRACT

The thermal denaturation of yeast enolase 1 was studied by differential scanning calorimetry (DSC) under conditions of subunit association/dissociation, enzymatic activity or substrate binding without turnover and substrate analogue binding. Subunit association stabilizes the enzyme, that is, the enzyme dissociates before denaturing. The conformational change produced by conformational metal ion binding increases thermal stability by reducing subunit dissociation. 'Substrate' or analogue binding additionally stabilizes the enzyme, irrespective of whether turnover is occurring, perhaps in part by the same mechanism. More strongly bound metal ions also stabilize the enzyme more, which we interpret as consistent with metal ion loss before denaturation, though possibly the denaturation pathway is different in the absence of metal ion. We suggest that some of the stabilization by 'substrate' and analogue binding is owing to the closure of moveable polypeptide loops about the active site, producing a more 'closed' and hence thermostable conformation.


Subject(s)
Metals/pharmacology , Phosphonoacetic Acid/analogs & derivatives , Phosphopyruvate Hydratase/chemistry , Phosphopyruvate Hydratase/metabolism , Yeasts/enzymology , Anions , Calcium/metabolism , Calorimetry, Differential Scanning , Catalysis , Edetic Acid/chemistry , Enzyme Stability , Hydroxamic Acids/metabolism , Magnesium/pharmacology , Metals/chemistry , Phosphonoacetic Acid/metabolism , Phosphopyruvate Hydratase/drug effects , Potassium Chloride/chemistry , Protein Denaturation , Protein Subunits , Reproducibility of Results , Substrate Specificity
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