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PubMedDate not supplied

Diminished interferon-gamma production in gastric mucosa T lymphocytes after H. pylori eradication in duodenal ulcer patients.

BACKGROUND/AIMS: Helicobacter pylori (H. pylori) infects an estimated 50% of the world population; however, only a small proportion of individuals develop clinical symptoms of gastritis, peptic ulceration or gastric cancer. The variations in disease presentation may be due to differences in bacterial virulence and/or immune response to the pathogen. In a previous study we reported an increased expression of the IL-2 receptor in duodenal ulcer (DU) patients. The present study examines the expression of IL-2 receptor and intracellular lymphokine production in gastric mucosa infiltrating T lymphocytes in DU patients before and after H. pylori eradication. METHODOLOGY: T lymphocytes were isolated from gastric mucosa biopsies by using mechanical and enzymatic tissue desegregation. Ficoll-purified lymphocytes were incubated with monoclonal antibodies and analyzed by using 4-color flow cytometry analysis for the IL-2 receptor (CD25) and intracellular interferon-gamma (IFN-gamma) and IL-4 expression. Lymphocytes from 24 H. pylori-infected patients with severe gastric mucosa infiltration (G2 and G3 histological type in Sydney classification) were analyzed. RESULTS: We demonstrated a significant decrease in IL-2 receptor expression on gastric mucosa T cells 3 and 12 months after eradication of H. pylori. We also demonstrated a diminished IFN-gamma production 3 and 12 months after H. pylori eradication. CONCLUSIONS: Our results suggest that cellular immune activation in gastric mucosa is reversibly dependent on the presence of H. pylori.

Amoxicillin↗
PubMed2000

Brain-derived neurotrophic factor expands ocular dominance columns in visual cortex in monocularly deprived and nondeprived kittens but does not in adult cats.

Segregation and stabilization of thalamocortical afferents to eye-specific patches, so-called "ocular dominance (OD) columns," in visual cortex are hypothesized to be based on activity-dependent competition for trophic factors such as brain-derived neurotrophic factor (BDNF) between afferents representing the two eyes during the critical period of postnatal development. To test this hypothesis we observed effects of an intracortical infusion of BDNF on OD columns in monocularly deprived kittens and also compared effects between normal kittens and adult cats. BDNF had a hypertrophic action on afferents irrespective of visual inputs so that it desegregated OD columns in the visual cortex of deprived and normal kittens, but this action was not seen in the adults, substantiating its hypothesized trophic role in plasticity of OD columns in the developing visual cortex.

Animals↗
PubMed1997

School finance: fifty years of expansion.

Since 1949-50, per-pupil expenditures in public elementary and secondary schools have more than quadrupled, even after adjusting for inflation. This article discusses some of the reasons. A significant share of the increase is the result of an 86% inflation-adjusted increase in teachers' salaries between 1949-50 and 1971-72, although teachers' salaries have changed little in the following 25 years. The ratio of students to school employees has dropped by half since 1949-50 as a result of declining class sizes and the hiring of more nonteaching school employees, which significantly affects costs. Even maintaining class size at a constant level will cause school budgets to grow at a rate greater than that of inflation because schools must compete in a labor market against other employers who are able to produce more with fewer employees. A substantial part of the increase in per-pupil spending is a result of expansions in services provided by the schools. More expensive, specialized classes for high school students, compensatory education for students from disadvantaged backgrounds, special education and related services for students with disabilities, and desegregation efforts all contribute to higher costs. Efforts to improve funding equity have led to increased expenditures: rather than take funding from wealthier districts, most states prefer to raise the funding available to schools at the bottom and the middle of the scale, increasing total spending. Finally, a share of the total increase must be attributed to the workings of the political system governing schools.

Adolescent↗
PubMed2000

Diminished Th1-type cytokine production in gastric mucosa T-lymphocytes after H. pylori eradication in duodenal ulcer patients.

Helicobacter pylori infects an estimated 50% of the world population, however only a small proportion of individuals develop clinical symptoms of gastritis, peptic ulceration or gastric cancer. The variations in disease presentation may be due to differences in bacterial virulence and/or immune response to the pathogen. In the previous study we reported an increased expression of the IL-2 receptor in duodenal ulcer (DU) patients infected with H. pylori. This study examined intracellular lymphokine production in gastric mucosa infiltrating T lymphocytes in DU patients before and after H. pylori eradication. T lymphocytes were isolated from gastric mucosa biopsies by using mechanical and enzymatic tissue desegregation. Ficoll-purified lymphocytes were incubated with monoclonal antibodies and analysed by using 3-colour flow cytometry analysis for intracellular interferon gamma (IFNgamma) and interleukin 4 (IL-4) expression in order to define Th1 and Th2 cell population. We demonstrated a significant decrease in the proportion of Th1 cells infiltrating gastric mucosa 6 and 12 months after H. pylori eradication. Our results suggest the importance of the local immune response in the development of H. pylori related gastritis.

Cytokines↗
PubMed2000

[Effect of mitomycin C on corneal endothelium cells. In vitro study].

PURPOSE: Mitomycin C is an antibiotic with a demonstrated antiproliferative capacity as an inhibitor of fibroblastic cells proliferation. Its use has been extended in glaucoma surgery. In the present study, we evaluated mitomycin C effect on cell culture monolayer of rabbit corneal endothelium. METHODS: The source of corneal endothelium for cell culture was New Zealand albino rabbit eyes. Desegregation of cells was carried out with mechanic and enzymatic dissociation from corneal endothelium and Descemet membrane. Culture medium was EMEM. Three treatment groups of plates were exposed to three different concentrations of mitomycin C 2x10(-3) mg/ml, 2x10(-2) mg/ml and 2x10(-1) mg/ml. Control and witness plate groups were also established. The morphometric study was performed through quantitative analysis with a video system connected to the light microscope. RESULTS: Different morphological changes related with cell size, cytoplasm and dyeing were seen at the morphological study and several degenerative signs were established indicating cellular death and a very decrease of the cellular population. In the groups treated with minimal dose (2x10(-3) mg/ml) and 3 days evolution time, cellular population was 434 cels/mm(2), 7 evolution days group cell density was 300.97cels/mm(2), and at 14 days it was 201.88 cels/mm(2). The percentage of survival in all the groups of treated cells was under 50%. CONCLUSIONS: Mitomycin C in concentrations and exposure time as used in this study has a potent lethal effect on this cellular type that compromises to a greater or smaller extent their function and integrity.

Animals↗
PubMedDate not supplied

Hugo A. Owens: dentist, civil rights leader, politician.

For 44 years Dr Hugo A. Owens was a distinguished practitioner and community leader in Portsmouth and Chesapeake, Virginia, and also served for a time as president of the National Dental Association. Besides his proclivity for dentistry, he was driven by two other passions: politics and civil rights. In 1970 he was one of the first African Americans ever elected to the Chesapeake City Council. He was reelected for the next term and appointed vice mayor, a position he held for 8 years. His political successes were preceded by his activities as a civil rights leader, which began in 1950 and lasted through the 1960s. In a remarkable series of negotiations and litigations, Dr Owens was the prime mover in the desegregation of the city of Portsmouth. In all three "careers," Dr Owens used dentistry as a home base for the expression of his activist philosophy of providing help for others when they were unable to help themselves.

Civil Rights↗
PubMed1999

Dental caries status of 5-7 year old children in three districts in Tanzania, Uganda and Mozambique.

This paper presents the baseline data of a longitudinal study assessing the dental caries status of 5-7 year old children in Tanzania, Uganda and Mozambique. Approximately one hundred 5-7 year-old-children from randomly selected schools in each of three locations (formal urban, informal urban and rural) were examined using the 1997 WHO Oral Health Survey Criteria. Thirty nine percent of the entire sample were found to bc caries-free, however this differed from location to location and from country to country. The overall mean dmft was 2.4 (SD 2.8), with the decayed component being 2.0 and the missing component 0.4. Of the children examined, only three had filled teeth. The mean dmft was significantly higher (p-value < 0.05) in Tanzania and Uganda than in Mozambique. There were also significant differences in the mean dmft between the various locations in Uganda and Mozambique. The prevalence of dental caries was not consistent across the formal urban, informal urban and rural locations in the three countries studied. It is thus essential to desegregate oral health status data to the most local level possible.

Child↗
PubMed2002

Sensitivity analysis and auto-calibration of an integral dynamic model for river water quality.

ESWAT--Extended Soil and Water Assessment Tool--was developed to allow for an integral modelling of the water quantity and quality processes in river basins. ESWAT is a physically based, semi-distributed model, with a moderate-to-large number of parameters and input and output variables (depending on the desegregation scheme). An auto-calibration procedure was implemented for the optimisation of the process parameters. The procedure is based on a new approach for multi-objective calibration and incorporates the algorithms of the Shuffled Complex Evolution Method. The optimisation uses a global optimisation criterion, whereby several output variables can be taken into account simultaneously. A statistical method enables the aggregation of the objective functions for individual variables, hereby avoiding the weighting problem. To select the important parameters for the optimisation, a sensitivity analysis precedes the calibration. The latter analysis is based on the One-factor-At-a-Time (OAT) design approach. The sensitivity analysis and the calibration procedure are applied to the river Dender in Belgium. The river is characterised by high pollution loads and long residence times in summer periods.

Calibration↗
PubMed2002

The malignant epidemic--changing patterns of trauma.

OBJECTIVES AND SETTING: The worldwide burden of trauma is increasing, but is unequally distributed between nations. Trauma in South Africa targets the young and productive in society and imposes a major burden on the health infrastructure. We undertook a review of injury trends among patients attending the Johannesburg Hospital Trauma Unit (JHTU) and the Johannesburg Medicolegal Laboratory (JMLL) in order to document the evolution in patterns of trauma over a 17-year period of great social and political change. DESIGN, SUBJECTS AND OUTCOME MEASURES: This was a retrospective review of all priority-one patients attending the JHTU from January 1985 to December 2001. The JHTU trauma database was used to retrieve information on patient demographics, wound mechanism and injury severity. The database at the JMLL, maintained since 1996, was examined and the manner and place of death were analysed. RESULTS: The JHTU has seen an unprecedented increase in the number of trauma patients over the last 17 years. The patients' demographic profiles have altered and injury is now predominantly due to interpersonal violence. Unnatural deaths examined at the JMLL have declined by 19% since 1996; however, the proportion of those deaths due to gunshot wounds has risen. CONCLUSIONS: The social and political changes in South Africa in recent years have led to changes in the injury profiles seen at the JHTU. Part of the increase can be explained by desegregation and a reduction in the provision of local hospital services; however, the impact of urbanisation within South Africa, cross-border migration and the high incidence of substance abuse are recognised. Evidence supports the implementation of legislative, environmental, social and behavioural interventions to contain and reduce the incidence and impact of violence and injury. Concerted efforts must be made at all levels to curb South Africa's trauma epidemic.

Age Distribution↗
PubMed2003

Field study on the choice of friends in two multi-racial pre-schools (South Africa/London).

The present research examined the influence of the two independent variables sex and race on the choice of friends in pre-school children. Data for this investigation were collected in two pre-schools, one situated in Stellenbosch, South Africa, the other in London, U.K. Both schools have in common that they accommodate children of different racial backgrounds (black, white, and coloured children), but the children's experience with desegregated classrooms differ. Friendship was operational defined with thirteen categories, summarized to the basic category pro-social behaviour. Fifty hours of free-play time were taped with one video camera in South Africa, and hundred hours were taped with two video cameras in London. The results showed that sex and race interact in their effect on the choice of friends. In South Africa race is supposed to be a strong indicator for friendship choices, especially for black children, whereas the black children in London choose friends more or less on the basis of sex.

Black People↗
PubMed2003

[Assessment of cancer cost at the international level : challenges and methodological approaches].

Historically health care data and especially health care cost rigid were not collected by disease. This is due on one side to a lack of readily available information on the diagnosis that lend to the health care given and on the other side to the diversity of actors and organizations taking charge of patients. This results in a major difficulty of linking together incompatible and separate data. A few countries have tried to desegregate their global health cost data in a top-down approach. The limits of such undertakings appeared however quickly, not the least because of the difficulties in allocating the expenditures by sector and disease. Other approaches, probably more fecund in the long run, such as the one used by the SEER-Medicare database in the U.S. favour the linkage of individual patient clinical and cost data in a bottom-up approach. However one should not ignore the potential bias problems raised, by the use of even large databases such as this one. A major advantage of clinical trials for costing purposes it that they include homogeneous groups of patients randomly allocated to several treatments for comparative purposes. They are therefore potentially better adapted for comparing new treatments with standard reference care.

Costs and Cost Analysis↗
PubMed2005

Use of seat belts in rural Alberta: an observational analysis.

OBJECTIVE: This paper details an observational study that estimates rates for wearing seat belts in rural Alberta and compares them with rates derived from a similar study conducted in 1999. METHOD: Direct observations of drivers and front-seat passengers of 72,593 light-duty vehicles were carried out at 334 survey locations in communities with populations of fewer than 25,000, throughout northern, central and southern Alberta. In addition to seat belt use, information collected included vehicle type, gender of drivers and passengers and, at intersections controlled by a stop sign, whether or not the vehicle came to a complete stop. RESULTS: The results indicate that in 2001 in rural Alberta the estimated proportion of driver and front-seat passengers of light-duty vehicles using seat belts was 76.1%. When compared with 1999 data, this represents a 6.9% increase in seat belt wearing rates. The data was desegregated further to show differential wearing rates between drivers of different vehicle types, males and females, drivers and passengers, and between those who came to a complete stop at a stop sign and those who did not. The time of day in which data collection took place also had some influence on seat belt wearing rates. DISCUSSION: This study contributes valuable information to programs and initiatives that aim to increase the use of seat belts in rural Alberta.

Accidents, Traffic↗
PubMed2005

Paying fairly for good outcomes: which formula works?

I see the single-based payment systems moving more toward the middle, toward an American-style system using competitive bidding with outcomes-based focus. The American system is moving in the opposite direction despite knowledge of the flaws of a single-payment system. Modernizing our payment system by desegregating Medicare Part A and Part B, applying information technology, and value-based reimbursement along with a bold move toward an HSA methodology could empower patients and physicians, reinvigorate our system with cost savings, and move us in the direction that all industries in a free market system should have the freedom to move.

Humans↗
PubMed1991

Chronic application of NMDA decreases the NMDA sensitivity of the evoked tectal potential in the frog.

The activity-dependent mechanism that refines the topography of the retinotectal projection in frogs is mediated by the NMDA receptor. Earlier studies found that chronic treatment of the optic tectum with the NMDA receptor antagonist DL-2-amino-5-phosphonovaleric acid (DL-AP5) desegregated eye-specific stripes in three-eyed frogs, while chronic treatment with NMDA sharpened stripe borders (Cline et al., 1987; Cline and Constantine-Paton, 1990). We now report that this same chronic treatment with NMDA decreases the electro-physiologically measured sensitivity of the optic tectum to applied NMDA: acute application of a given concentration of NMDA decreased the evoked tectal potential to a lesser extent in animals chronically treated with NMDA than it did in normal and sham-treated animals. This is observed as a shift to the right in the NMDA dose-response curves for both the positive and negative postsynaptic components of the evoked tectal response. We believe that this decreased NMDA receptor effectiveness further restricts the intermingling of axon branches from the two eyes by limiting synapse stabilization to areas where afferent activity is most correlated. This would account for the anatomical sharpening of stripe borders (i.e., increased afferent segregation). Quantitative autoradiographic analysis of 3H-glutamate binding to NMDA receptors indicated that binding densities within the tectum did not differ between control groups and NMDA chronically treated groups. We suggest that in the experimental animals the response to NMDA may be decreased by a change in the effectiveness of individual NMDA receptors rather than by decreases in receptor number. This experimentally induced change may be analogous to naturally occurring decreases in receptor function that correlate with the end of some periods of visual plasticity in mammals.

2-Amino-5-phosphonovalerate↗
PubMedDate not supplied

[Accumulation of UV-induced radicals in proteins with various degree of aggregation].

Accumulation of radicals UV-induced in protein solutions at 77 K was investigated. It has been found that in each molecule of small proteins true solutions only one ionization proceeds and two radicals are formed. The limiting number of radicals per one protein molecule decreases with the increase of their aggregation level. A method is suggested for observing aggregation and desegregation processes in proteins, as well as a method for determining the absolute concentration of radicals.

Animals↗
PubMedDate not supplied

Multiple sclerosis. I. The immune pathogenetic hypothesis.

Animal models indicate that chronic relapsing demyelinating diseases of the central nervous system (CNS) can be induced both by certain viruses and by sensitization to myelinic antigens. Epidemiological data (studies on emigrants and on so-called "Multiple Sclerosis (MS) epidemics") suggest that an environmental transmissible agent, acting on a genetic substrate, could play a role in the pathogenesis of the disease. The transmissible agent could be a virus. Data to this effect are insufficiently indicative, but the hypothesis has been recently put forward that it could be antigenically related to the lymphotropic viruses (HTLV). The transmissible agent could act either by desegregating myelinic antigens or by inducing an alteration of the immune system with a reduction of T lymphocyte suppressor activity. There appears to be rapid and intense activated T lymphocyte "traffic" across the blood-brain barrier in patients affected with MS. Cells specifically sensitized to the unknown antigen find within the CNS other cells able to perpetuate presentation of the antigen (HLA-DR+ astrocytes and endothelial cells, not present in normal brain) and then activate the macrophages which in turn begin immuno-mediated phagocytosis of the healthy myelin. Aspecific immune cells are also recruited into CNS where seem to abnormally proliferate (possibly owing to reduced suppressor activity) producing antibodies against various viral or cerebral antigens which are not clearly related to the pathogenesis of the disease (production of intra-CNS "nonsense" antibodies and synthesis of the oligoclonal immunoglobulin bands seen at the cerebrospinal fluid electrophoresis.)

Antibodies, Monoclonal↗
PubMed1985

[Anti-thixotropic therapy in arterial occlusive disorders: What is the effectiveness of "rheological procedures" in the presence of persisting obliterations?].

In the attempt to illustrate the pathogenetic (and thence the clinical) significance of the anomalous properties of the human blood, we have earlier proposed to use the term "thixotropy" for describing all those rheological anomalies of the blood, which are responsible for the reversible loss of blood fluidity at low rates of shear. "Thixotropy" is a tendency which is present even in normal human blood, but is much more pronounced in the blood of many vascular patients due to exaggerated red cell aggregation and due to red cell "rigidity". This tendency manifests itself when the flow forces are reduced by interfering with the fluidity of the blood. It has no effect on the viscous resistance of the rapidly flowing blood. Most of all, the effect of thixotropy of the blood depends on the haematocrit level, both in normal blood and in the blood of patients: when associated with anaemia, the thixotropic tendency is largely irrelevant, while it gains significance with each increase in the haematocrit level. Theoretically justified by the described premise, the rheological treatments can now be classified as "anti-thixotropic therapies". In the present review, the principle of therapeutic defibrinogenation and of plasmapheresis are discussed as consequences of the resulting desegregation, the principle of isovolemic haemodilution is interpreted as the most effect antithixotropic procedure owing to its profound effect on haematocrit value and thence thixotropic potential.

Arterial Occlusive Diseases↗
PubMed1981

Some further observations on the index of residential differentiation.

The relationship between the index of residential differentiation (RDI), a recently introduced measure of residential segregation which is designed to summarize the distribution of c social groups in a single index, and the indices of dissimilarity (D) and segregation (SI) is examined. It is demonstrated that RDI is a natural extension of D, and that when c = 2, RDI = D; when c greater than 2, it is possible to stipulate RDI in terms of SI, but it is not possible to stipulate RDI in a straightforward manner in terms of D. An adjusted RDI is then suggested in which random segregation rather than complete desegregation is used as the baseline.

Demography↗