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1.
Vaccine ; 36(32 Pt B): 4952-4957, 2018 08 06.
Article in English | MEDLINE | ID: mdl-30037485

ABSTRACT

BACKGROUND: Government agencies, healthcare accreditation bodies and quality improvement organizations support the development of new quality measures. Composite quality measures use more than one measure to develop a broader assessment of healthcare system function. Currently, no composite measures for adult immunization coverage exist. Development of such measures could facilitate improvements in adult immunization coverage by focusing on measurement of receipt of all age-recommended vaccines. METHODS: We recruited five Indian Health Service (IHS) and Tribal health clinics to pilot an Adult Immunization Composite Measure (AICM). Data were collected monthly over seven months using a pre-programmed electronic health record (EHR) reporting tool (IHS sites); Tribal sites used third-party software or a programmable EHR reporting function. Data collected included: number of adults aged 19 years and over who were active users of the facility with at least two visits in the last three years; the cumulative number fully immunized per age-based recommendations for tetanus toxoid-containing vaccines, pertussis, zoster and pneumococcal vaccines; and the percent immunized for the AICM and for each individual vaccine. Coverage was calculated for three age groups: 19-59 years; 60-64 years; and 65 years and older. RESULTS: All sites reported aggregate immunization data monthly from patient EHR records. For all adults 19 years and older, AICM coverage ranged from 49% to 87% at the end of the report period. Two sites showed increases in AICM coverage ≥ 3%. Improvements in zoster vaccine coverage accounted for most of the increase observed. One site specifically focused on improving zoster coverage as a result of using the AICM. CONCLUSIONS: We demonstrated the feasibility of implementing a composite measure of adult immunization coverage. This is the first measure capable of monitoring immunization completeness, coverage improvement and overall adult vaccine program effectiveness for adults who receive all recommended, age-based vaccines.


Subject(s)
Immunization/methods , Aged , Female , Humans , Immunization/statistics & numerical data , Indians, North American , Infant , Male , United States , United States Indian Health Service , Vaccination
2.
Strategies Trauma Limb Reconstr ; 11(1): 13-8, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26993111

ABSTRACT

The aim of this study was to characterise severe open tibial shaft fractures sustained by the UK military personnel over 10 years of combat in Iraq and Afghanistan. The UK military Joint Theatre Trauma Registry was searched for all such injuries, and clinical records were reviewed for all patients. One hundred Gustilo-Anderson III tibia fractures in 89 patients were identified in the 10 year study period; the majority sustained injuries through explosive weapons (63, 68 %) with the remainder being injured from gunshot wounds. Three fractures were not followed up for 12 months and were therefore excluded. Twenty-two (23 %) of the remaining 97 tibial fractures were complicated by infection, with S. aureus being the causative agent in 13/22 infected fractures (59 %). Neither injury severity, mechanism, the use of an external fixator, the need for vascularised tissue transfer nor smoking status was associated with subsequent infection. Bone loss was significantly associated with subsequent infection (p < 0.0001, Fisher's exact test). This study presents 10 years of open tibial fractures sustained in Iraq and Afghanistan. Most infection in combat open tibia fractures is caused by familiar organisms, i.e. S. aureus. While the overall severity of a casualty's injuries was not associated with infection, the degree of bone loss from the fracture was.

3.
4.
Arch Dis Child ; 96(9): 863-9, 2011 Sep.
Article in English | MEDLINE | ID: mdl-20656732

ABSTRACT

Epigenetic mechanisms are believed to play an important role in disease, development and ageing with early life representing a window of particular epigenomic plasticity. The knowledge upon which these claims are based is beginning to expand. This review summarises evidence pointing to the determinants of epigenetic patterns, their juxtaposition at the interface of the environment, their influence on gene function and the relevance of this information to child health.


Subject(s)
Child Development/physiology , Epigenesis, Genetic/genetics , Child , DNA Methylation/genetics , Environment , Epigenomics/methods , Gene Expression Regulation, Developmental/genetics , Genetic Predisposition to Disease , Genome , Humans , Phenotype
5.
Bone ; 46(4): 952-6, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20080222

ABSTRACT

It has been suggested that bone health in adulthood is programmed by development in utero. Most previous investigations addressing this topic have focussed on bone mineral density or content, rather than other indicators of bone health, such as biochemical markers of bone turnover. This study investigated whether potential predictors, from different stages of life, influence bone resorption in men aged 49-51years in the Newcastle Thousand Families birth cohort. The cohort originally consisted of all 1142 births in the city of Newcastle upon Tyne, UK in May and June 1947. Detailed information was collected prospectively during childhood, including birth weight and socio-economic circumstances. At 49-51years of age, 574 study members completed a detailed 'Health and Lifestyle' questionnaire, including the European Prospective Investigation of Cancer (EPIC) food frequency questionnaire and 412 study members attended for clinical examination, including 172 men in whom bone resorption was assessed by measurement of serum beta C-telopeptide of type 1 collagen (CTX). A significant trend was seen between increasingly disadvantaged socio-economic status at birth and increased bone resorption (p=0.04, r-squared 2.6%). However, birth weight, standardised for sex and gestational age, was not associated with serum CTX (p=0.77, r-squared 0.05%). Significant trends were also seen between increasing total energy intake (p=0.03, r-squared 2.9%), dietary intake of saturated fat (p=0.02, r-squared 2.6%), protein (p=0.04, r-squared 2.5%) and carbohydrates (p=0.04, r-squared 2.6%) and higher serum CTX. However, on adjustment for total energy intake, none of the other dietary variables was significant at the univariate level maintained significance. Our findings suggest that early socio-economic disadvantage and later dietary factors may be associated with increased bone resorption in middle aged men. However, as little of the variance in serum CTX was explained by the variables included within this investigation, further longitudinal studies, with sufficient statistical power, are required to assess predictors of bone resorption in adulthood and their relative importance.


Subject(s)
Bone Resorption/blood , Collagen Type I/blood , Dietary Carbohydrates/blood , Dietary Fats/blood , Health Status , Peptides/blood , Biomarkers/blood , Bone Resorption/physiopathology , Chi-Square Distribution , Energy Intake/physiology , Humans , Life Style , Male , Middle Aged , Prospective Studies , Regression Analysis , Socioeconomic Factors , Surveys and Questionnaires
6.
Neuroscience ; 147(3): 664-73, 2007 Jul 13.
Article in English | MEDLINE | ID: mdl-17560040

ABSTRACT

Multiple sclerosis (MS) is a disease of the CNS in which inflammation, demyelination and neurodegeneration contribute to its initiation and progression. A frequently employed model of MS is experimental autoimmune encephalomyelitis (EAE). Here, to gain new insights into the disease process, an analysis of proteins in extracts of lumbar spinal cord from naïve and EAE rats was undertaken. The data mainly confirm that inflammation and blood-brain barrier (BBB) breakdown are the major hallmarks of disease in this model. Given their importance in the BBB, junctional proteins were further investigated. Occludin, a protein localizing to tight junctions in brain endothelial cells, showed strikingly increased migration in EAE when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). This increased migration was mimicked by in vitro phosphatase treatment, implying its dephosphorylation in EAE. Occludin dephosphorylation coincided with the onset of inflammation, slightly preceding visible signs of disease, and was just prior to apparent changes in BBB permeability. These findings suggest occludin is a target for signaling processes in EAE, perhaps regulating the response of the BBB to the inflammatory environment as seen in MS.


Subject(s)
Encephalitis/metabolism , Encephalomyelitis, Autoimmune, Experimental/metabolism , Encephalomyelitis, Autoimmune, Experimental/pathology , Membrane Proteins/metabolism , Animals , Disease Models, Animal , Electrophoresis, Gel, Two-Dimensional/methods , Encephalitis/etiology , Encephalitis/pathology , Encephalomyelitis, Autoimmune, Experimental/complications , Endothelial Cells/cytology , Female , Immunoprecipitation/methods , Mass Spectrometry/methods , Occludin , Phosphoric Monoester Hydrolases/pharmacology , Phosphorylation/drug effects , Rats , Rats, Inbred Lew , Spinal Cord/pathology , Tight Junctions/metabolism
8.
Phys Med Biol ; 51(10): 2367-81, 2006 May 21.
Article in English | MEDLINE | ID: mdl-16675858

ABSTRACT

The identification and quantification of tumour volume measurement variability is imperative for proper study design of longitudinal non-invasive imaging of pre-clinical mouse models of cancer. Measurement variability will dictate the minimum detectable volume change, which in turn influences the scheduling of imaging sessions and the interpretation of observed changes in tumour volume. In this paper, variability is quantified for tumour volume measurements from 3D high-frequency ultrasound images of murine liver metastases. Experimental B16F1 liver metastases were analysed in different size ranges including less than 1 mm3, 1-4 mm3, 4-8 mm3 and 8-70 mm3. The intra- and inter-observer repeatability was high over a large range of tumour volumes, but the coefficients of variation (COV) varied over the volume ranges. The minimum and maximum intra-observer COV were 4% and 14% for the 1-4 mm3 and <1 mm3 tumours, respectively. For tumour volumes measured by segmenting parallel planes, the maximum inter-slice distance that maintained acceptable measurement variability increased from 100 to 600 microm as tumour volume increased. Comparison of free breathing versus ventilated animals demonstrated that respiratory motion did not significantly change the measured volume. These results enable design of more efficient imaging studies by using the measured variability to estimate the time required to observe a significant change in tumour volume.


Subject(s)
Algorithms , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/secondary , Ultrasonography/methods , Animals , Information Storage and Retrieval/methods , Mice , Observer Variation , Reproducibility of Results , Sensitivity and Specificity
9.
DNA Repair (Amst) ; 3(8-9): 1219-25, 2004.
Article in English | MEDLINE | ID: mdl-15279810

ABSTRACT

Comparison of the clinical and cellular phenotypes of different genomic instability syndromes provides new insights into functional links in the complex network of the DNA damage response. A prominent example of this principle is provided by examination of three such disorders: ataxia-telangiectasia (A-T) caused by lack or inactivation of the ATM protein kinase, which mobilises the cellular response to double strand breaks in the DNA; ataxia-telangiectasia-like disease (ATLD), a result of deficiency of the human Mre11 protein; and the Nijmegen breakage syndrome (NBS), which represents defective Nbs1 protein. Mre11 and Nbs1 are members of the Mre11/Rad50/Nbs1 (MRN) protein complex. MRN and its individual components are involved in different responses to cellular damage induced by ionising radiation and radiomimetic chemicals, including complexing with chromatin and with other damage response proteins, formation of radiation-induced foci, and the induction of different cell cycle checkpoints. The phosphorylation of Nbs1 by ATM would indicate that ATM acts upstream of the MRN complex. Consistent with this were the suggestions that ATM could be activated in the absence of fully functional Nbs1 protein. In contrast, the regulation of some ATM target proteins, e.g. Smc1 requires the MRN complex as well as ATM. Nbs1 may, therefore, be both a substrate for ATM and a mediator of ATM function. Recent studies that indicate a requirement of the MRN complex for proper ATM activation suggest that the relationship between ATM and the MRN complex in the DNA damage response is yet to be fully determined. Despite the fact that both Mre11 and Nbs1 are part of the same MRN complex, deficiency in either protein in humans does not lead to the same clinical picture. This suggests that components of the complex may also act separately.


Subject(s)
Ataxia Telangiectasia/diagnosis , Ataxia Telangiectasia/genetics , DNA Damage , Alleles , Ataxia Telangiectasia Mutated Proteins , Cell Cycle , Cell Cycle Proteins/genetics , Cell Cycle Proteins/physiology , Chromatin/metabolism , Chromosomal Proteins, Non-Histone/physiology , DNA-Binding Proteins/genetics , Histones/chemistry , Humans , MRE11 Homologue Protein , Models, Genetic , Mutation , Nuclear Proteins/genetics , Phenotype , Phosphorylation , Protein Serine-Threonine Kinases/genetics , Radiation, Ionizing , S Phase , Syndrome , Tumor Suppressor Proteins
10.
JAMA ; 286(10): 1201-5, 2001 Sep 12.
Article in English | MEDLINE | ID: mdl-11559265

ABSTRACT

CONTEXT: Until recently, methicillin-resistant Staphylococcus aureus (MRSA) infections have been acquired primarily in nosocomial settings. Four recent deaths due to MRSA infection in previously healthy children in the Midwest suggest that serious MRSA infections can be acquired in the community in rural as well as urban locations. OBJECTIVES: To document the occurrence of community-acquired MRSA infections and evaluate risk factors for community-acquired MRSA infection compared with methicillin-susceptible S aureus (MSSA) infection. DESIGN: Retrospective cohort study with medical record review. SETTING: Indian Health Service facility in a rural midwestern American Indian community. PATIENTS: Patients whose medical records indicated laboratory-confirmed S aureus infection diagnosed during 1997. MAIN OUTCOME MEASURES: Proportion of MRSA infections classified as community acquired based on standardized criteria; risk factors for community-acquired MRSA infection compared with those for community-acquired MSSA infection; and relatedness of MRSA strains, determined by pulsed-field gel electrophoresis (PFGE). RESULTS: Of 112 S aureus isolates, 62 (55%) were MRSA and 50 (45%) were MSSA. Forty-six (74%) of the 62 MRSA infections were classified as community acquired. Risk factors for community-acquired MRSA infections were not significantly different from those for community-acquired MSSA. Pulsed-field gel electrophoresis subtyping indicated that 34 (89%) of 38 community-acquired MRSA isolates were clonally related and distinct from nosocomial MRSA isolates found in the region. CONCLUSIONS: Community-acquired MRSA may have replaced community-acquired MSSA as the dominant strain in this community. Antimicrobial susceptibility patterns and PFGE subtyping support the finding that MRSA is circulating beyond nosocomial settings in this and possibly other rural US communities.


Subject(s)
Indians, North American , Methicillin Resistance , Staphylococcal Infections/epidemiology , Staphylococcus aureus/drug effects , Community-Acquired Infections/epidemiology , Electrophoresis, Gel, Pulsed-Field , Humans , Midwestern United States/epidemiology , Retrospective Studies , Risk Factors , Rural Population , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Staphylococcus aureus/genetics
11.
Semin Cancer Biol ; 11(4): 271-6, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11513562

ABSTRACT

Metastasis can occur many years after primary tumour treatment. However, the status of the tumour during this period of dormancy is poorly understood. As part of our ongoing experimental studies on mechanisms of metastasis, we have discovered that large numbers of disseminated single cells may persist in secondary sites for extended time periods. Identification of these cells was facilitated by in vivo techniques developed to quantify the fate of individual cells during the metastatic process. Here we review these in vivo techniques and findings. We also discuss the potential clinical implications if dormant solitary cells exist in appreciable numbers in cancer patients.


Subject(s)
Neoplasms/pathology , Animals , Cell Division , Cell Survival , Humans , Neoplasm Metastasis/pathology , Neoplasms/therapy , Neoplastic Cells, Circulating
12.
Clin Infect Dis ; 33(7): 990-6, 2001 Oct 01.
Article in English | MEDLINE | ID: mdl-11528570

ABSTRACT

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged among patients in the general population who do not have established risk factors for MRSA. Records from 10 Minnesota health facilities were reviewed to identify cases of MRSA infection that occurred during 1996-1998 and to identify which cases were community acquired. Susceptibility testing and pulsed-field gel electrophoresis (PFGE) subtyping were performed on available isolates. A total of 354 patients (median age, 16 years) with community-acquired MRSA (CAMRSA) infection were identified. Most case patients (299 [84%]) had skin infections, and 103 (29%) were hospitalized. More than 90% of isolates were susceptible to all antimicrobial agents tested, with the exception of beta-lactams and erythromycin. Of 334 patients treated with antimicrobial agents, 282 (84%) initially were treated with agents to which their isolates were nonsusceptible. Of 174 Minnesota isolates tested, 150 (86%) belonged to 1 PFGE clonal group. CAMRSA infections were identified throughout Minnesota; although most isolates were genetically related and susceptible to multiple antimicrobials, they were generally nonsusceptible to initial empirical therapy.


Subject(s)
Anti-Bacterial Agents/pharmacology , Methicillin Resistance , Staphylococcal Infections/epidemiology , Staphylococcus aureus , Adolescent , Adult , Aged , Bacterial Typing Techniques , Child , Child, Preschool , Community-Acquired Infections/epidemiology , Community-Acquired Infections/microbiology , Electrophoresis, Gel, Pulsed-Field , Female , Hospitals , Humans , Infant , Male , Microbial Sensitivity Tests , Middle Aged , Minnesota/epidemiology , Staphylococcal Infections/microbiology , Staphylococcus aureus/classification , Staphylococcus aureus/drug effects , Staphylococcus aureus/genetics
13.
Surg Oncol Clin N Am ; 10(2): 243-55, vii, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11382585

ABSTRACT

Metastasis is responsible for most cancer deaths. A better understanding of the process provides opportunities to develop new treatments to prevent metastasis. This article summarizes findings from experimental in vivo videomicroscopy and quantitative studies on metastatic inefficiency, which indicate that early steps in hematogenous metastasis may be quite efficient, but that regulation of cancer cell growth in secondary sites determines metastatic outcome. The authors have identified three key stages of this growth regulation: survival of a subset of single cells, proliferation of a subset of these cells to form preangiogenic micrometastases, and persistence of growth of a subset of these to form vascularized metastases. Formation of clinically relevant metastases is determined by the proportion of cells that proceeds successfully through each stage, and surviving single cells and preangiogenic micrometastases both represent possible sources of tumor dormancy.


Subject(s)
Cell Transformation, Neoplastic/ultrastructure , Neoplasm Invasiveness/ultrastructure , Neoplastic Cells, Circulating/ultrastructure , Neovascularization, Pathologic/pathology , Animals , Disease Models, Animal , Humans , Microscopy, Video
15.
Cancer Res ; 60(9): 2541-6, 2000 May 01.
Article in English | MEDLINE | ID: mdl-10811137

ABSTRACT

Cancer metastasis is an inefficient process. The steps in metastasis responsible for this inefficiency and how metastatic inefficiency can vary in different locations within an organ remain poorly understood. B16F10 cells were injected to target mouse lung, and at sequential times thereafter we quantified in lung the time course of: (a) overall cell survival and metastatic development; and (b) local cell survival and growth with respect to the lung surface and specific interior structures. We found high rates of initial survival of cells trapped in the lung circulation, extravasation into lung tissue, and subsequent survival of extravasated solitary cells (74% at day 3) before metastasis formation. However, at the time of initial replication of metastatic cells a major loss of cells occurred. Although only a small proportion of injected cells started to form metastases, most of these developed into macroscopic tumors. Solitary cells found at later times were dormant. Thus, overall metastatic inefficiency was largely due to postextravasation events affecting solitary cells. Regionally within the lung, cells and metastases were randomly distributed to day 4, but by day 10 preferential tumor growth was found along the lung surface and around arterial and venous vessels. Thus, trapping and early growth of injected cells was unaffected by location within the lung, whereas subsequent metastatic growth was enhanced in specific microenvironments. This study: (a) quantifies early temporal and spatial progression of metastasis in lung; (b) documents persistence of solitary dormant cells; and (c) shows that metastatic inefficiency depends on the initiation of growth in a subset of extravasated cells, whereas continued growth of metastases occurs preferentially in specific tissue environments.


Subject(s)
Lung Neoplasms/pathology , Melanoma/pathology , Neoplasm Metastasis , Animals , Apoptosis , Cell Survival , Disease Progression , Female , In Situ Nick-End Labeling , Mice , Mice, Inbred C57BL , Time Factors , Tissue Distribution , Tumor Cells, Cultured
16.
Adv Cancer Res ; 79: 91-121, 2000.
Article in English | MEDLINE | ID: mdl-10818678

ABSTRACT

Metastasis is responsible for most cancer deaths. Therapeutic strategies to prevent development of metastases thus have potential to impact on cancer mortality. Development of these therapies requires a better understanding of the biology and molecular events of the metastatic process. Metastasis is usually defined, clinically and experimentally, by evidence of the endpoint of the process, that is, the presence of metastatic tumors. Endpoint assays are suitable for determining if a therapeutic approach is effective, but can provide little information on how a treatment works in vivo and what steps in metastasis are affected. We describe here two methodological advances in the study of metastasis as a process: in vivo videomicroscopy, which permits direct observation of steps in metastasis, and a "cell accounting" technique that permits quantification of the fate of cells over time. These procedures have provided new and unexpected insights into the biology of the metastatic process. Based on these insights, we consider which steps in the metastatic process are biologically and clinically most appropriate as therapeutic targets for development of anti-metastasis therapies. We conclude that the most promising stage of the metastasis process for therapeutic targeting is the growth phase, after cancer cells have arrested in the microcirculation in secondary sites and have completed extravasation. Earlier phases in the process are either biologically inappropriate or clinically inaccessible, except in specific cases (e.g., chemoprevention strategies). The role of "seed" and "soil" in determining organ-specific metastasis is also discussed. The metastatic growth phase fortunately is a clinically broad target, and any treatment that limits growth of metastases prior to their causing irreversible harm to the patient has the potential to be clinically useful. A variety of therapeutic approaches to target this phase are under active development, including inhibition of angiogenesis or signal transduction pathways needed to support the growth of metastatic cells.


Subject(s)
Antineoplastic Agents/therapeutic use , Neoplasm Metastasis/drug therapy , Allantois/blood supply , Animals , Antineoplastic Agents/pharmacology , Cell Adhesion , Cell Count , Cell Division , Cell Movement , Cell Survival , Chickens , Chorion/blood supply , Drug Design , Humans , Liver Neoplasms, Experimental/secondary , Mice , Microcirculation , Microscopy, Video , Neoplasm Transplantation , Neoplastic Cells, Circulating , Neoplastic Stem Cells/pathology , Organ Specificity
17.
Public Health Rep ; 115(5): 469-75, 2000.
Article in English | MEDLINE | ID: mdl-11236019

ABSTRACT

OBJECTIVE: Although the state of Oklahoma has traditionally reported very high incidence rates of Rocky Mountain spotted fever (RMSF) cases, the incidence of RMSF among the American Indian population of the state has not been studied. The authors used data from several sources to estimate the incidence of RMSF among American Indians in Oklahoma. METHODS: The authors retrospectively reviewed an Indian Health Service (IHS) hospital discharge database for 1980-1996 and available medical charts from four IHS hospitals. The authors also reviewed RMSF case report forms submitted to the Centers for Disease Control and Prevention (CDC) for 1981-1996. RESULTS: The study data show that American Indians in the IHS Oklahoma City Area were hospitalized with RMSF at an annual rate of 48.2 per million population, compared with an estimated hospitalization rate of 16.9 per million Oklahoma residents. The majority of cases in the IHS database (69%) were diagnosed based on clinical suspicion rather than laboratory confirmation. The incidence of RMSF for Oklahoma American Indians as reported to the CDC was 37.4 cases per million, compared with 21.6 per million for all Oklahoma residents (RR 1.7, 95% confidence interval [CI] 1.5, 2.1). CONCLUSIONS: Rates derived from the IHS database may not be comparable to state and national rates because of differences in case inclusion criteria. However, an analysis of case report forms indicates that American Indians n Oklahoma have a significantly higher incidence of RMSF than that of the overall Oklahoma population. Oklahoma American Indians may benefit from educationa campaigns emphasizing prevention of tick bites and exposure to tick habitats.


Subject(s)
Hospitals, Federal/statistics & numerical data , Indians, North American/statistics & numerical data , Rocky Mountain Spotted Fever/epidemiology , Centers for Disease Control and Prevention, U.S. , Disease Notification , Health Education , Hospitalization/statistics & numerical data , Humans , Incidence , Medical Records , Oklahoma/epidemiology , Population Surveillance , Retrospective Studies , United States/epidemiology , United States Indian Health Service
18.
Nat Med ; 6(1): 62-6, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10613825

ABSTRACT

Multiple sclerosis is an immune-mediated disorder of the central nervous system leading to progressive decline of motor and sensory functions and permanent disability. The therapy of multiple sclerosis is only partially effective, despite anti-inflammatory, immunosuppresive and immunomodulatory measures. White matter inflammation and loss of myelin, the pathological hallmarks of multiple sclerosis, are thought to determine disease severity. Experimental autoimmune encephalomyelitis reproduces the features of multiple sclerosis in rodents and in nonhuman primates. The dominant early clinical symptom of acute autoimmune encephalomyelitis is progressive ascending muscle weakness. However, demyelination may not be profound and its extent may not correlate with severity of neurological decline, indicating that targets unrelated to myelin or oligodendrocytes may contribute to the pathogenesis of acute autoimmune encephalomyelitis. Here we report that within the spinal cord in the course of autoimmune encephalomyelitis not only myelin but also neurons are subject to lymphocyte attack and may degenerate. Blockade of glutamate AMPA receptors ameliorated the neurological sequelae of autoimmune encephalomyelitis, indicating the potential for AMPA antagonists in the therapy of multiple sclerosis.


Subject(s)
Brain Stem/pathology , Encephalomyelitis, Autoimmune, Experimental/drug therapy , Encephalomyelitis, Autoimmune, Experimental/pathology , Excitatory Amino Acid Antagonists/therapeutic use , Neurons/pathology , Organophosphonates/therapeutic use , Quinoxalines/therapeutic use , Spinal Cord/pathology , Animals , Disease Models, Animal , Encephalomyelitis, Autoimmune, Experimental/physiopathology , Guinea Pigs , Motor Neurons/pathology , Multiple Sclerosis/pathology , Multiple Sclerosis/therapy , Muscle Tonus , Myelin Basic Protein/immunology , Rats , Rats, Inbred Lew , Receptors, AMPA/antagonists & inhibitors , Receptors, Kainic Acid/antagonists & inhibitors , Recurrence , Spinal Cord/ultrastructure , T-Lymphocytes/pathology
19.
Clin Exp Metastasis ; 17(2): 111-7, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10411102

ABSTRACT

Matrix metalloproteinases (MMPs) have been shown to contribute functionally to tumor metastasis. MMP inhibitors are thus being assessed for clinical utility as anti-metastatic therapeutics. Batimastat (BB-94) is a synthetic MMP inhibitor that has been shown to inhibit tumor growth and metastasis in mice. Here we assessed the ability of batimastat to inhibit liver metastases of murine B16F1 cells, after injection of cells in mice via mesenteric vein to target the liver. We then determined which of the sequential steps in metastasis were affected by batimastat, in order to identify its mechanism of action in vivo. Intravital videomicroscopy was used to assess the effect on extravasation, and a 'cell accounting' procedure was used to determine the effect on initial survival of cells. Stereological quantification of functional blood vessels was used to determine the effect on tumor vascularity, thereby avoiding problems associated with immunohistochemical detection of liver sinusoidal endothelial cells. We found that batimastat (50 mg/kg i.p. 5 h prior to and after cell injection, daily thereafter) resulted in a 23% reduction in mean diameter of liver metastases (equivalent to a 54% reduction in tumor volume), while not reducing the number of metastases. Extravasation of cells from the liver circulation was not affected: at 8, 24 and 48 h after injection of cells, the same proportion of cells had extravasated from treated vs. control mice. Batimastat also did not inhibit early survival of cells. However, batimastat-treated mice had a significantly reduced percentage vascular volume within liver metastases, indicating inhibition of angiogenesis. This study demonstrates in vivo that the mechanism by which batimastat limits growth of B16F1 metastases in liver is not by affecting extravasation, but by inhibiting angiogenesis within metastases. This finding suggests that MMP inhibitors may be appropriate for use in patients with metastatic cells that have already extravasated in secondary sites.


Subject(s)
Cell Movement/drug effects , Liver Neoplasms/blood supply , Liver Neoplasms/secondary , Melanoma, Experimental/pathology , Neovascularization, Pathologic , Phenylalanine/analogs & derivatives , Thiophenes/pharmacology , Animals , Cell Survival/drug effects , Injections, Intraperitoneal , Injections, Intravenous , Mesenteric Veins , Mice , Microscopy, Video , Phenylalanine/pharmacology , Tumor Cells, Cultured
20.
J Cell Sci ; 112 ( Pt 12): 1835-42, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10341203

ABSTRACT

High resolution intravital videomicroscopy has provided a powerful tool for directly observing steps in the metastatic process, and for clarifying molecular mechanisms of metastasis and modes of action of anti-metastasis therapeutics. Cells previously have been identified in vivo using exogenously added fluorescent labels, limiting observations to a few cell divisions, or by natural markers (e.g. melanin) expressed only by specific cell types. Here we tested the utility of stable green fluorescent protein (GFP)-transfected cells for monitoring and quantifying sequential steps in the metastatic process. Using CHO-K1 cells that stably express GFP, we document the visualization and quantification by intravital videomicroscopy of sequential steps in metastasis within mouse liver, from initial arrest of cells in the microvasculature to the growth and angiogenesis of metastases. Individual, non-dividing cells, as well as micro- and macrometastases could clearly be detected and quantified, as could fine cellular details such as pseudopodial projections, even after extended periods of in vivo growth. We quantified the size distribution of micrometastases and their locations relative to the liver surface using 50 micrometer thick formalin-fixed tissue sections. The data suggest preferential growth and survival of micrometastases near the liver surface. Furthermore, we observed a small population of single cells that persisted over the 11 day observation period, which may represent dormant cells with potential for subsequent proliferation. This study demonstrates the advantages of GFP-expressing cells, coupled with real-time high resolution videomicroscopy, for long-term in vivo studies to visualize and quantify sequential steps of the metastatic process.


Subject(s)
Liver/metabolism , Luminescent Proteins/biosynthesis , Neovascularization, Pathologic , Animals , CHO Cells , Cell Cycle/physiology , Cricetinae , Extravasation of Diagnostic and Therapeutic Materials , Green Fluorescent Proteins , Liver Neoplasms/blood supply , Liver Neoplasms/secondary , Mice , Microscopy, Video
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