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1.
J Surg Res ; 273: 132-137, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35085940

RESUMO

INTRODUCTION: Ownership may influence trauma center (TC) location. For-profit (FP) TCs require a favorable payor mix to thrive, whereas not-for-profit (NFP) centers may rely on government funding, grants, and patient volume. We hypothesized that the demographics of trauma patients would be different for NFP and FP TCs due to ownership type. We also hypothesized that these demographic differences might be associated with outcomes such as length of stay, reported complications, and mortality. METHODS: We used the Florida Agency for Health Care Administration (AHCA) 2016-2017 inpatient dataset to examine differences in outcomes by trauma center ownership type. Negative binomial and logistical regression was used to compare trauma ownership, length of stay (LOS), reported complications, and mortality of severely injured nonelderly adult trauma patients. RESULTS: Our study analyzed risk factors and outcomes for 10,700 trauma alert patients. Patients treated at FP TCs were less likely to be Black (OR 0.70, 95% CI: 0.62-0.78), to be uninsured (OR 0.40, 95% CI 0.36-0.45), have Medicare (OR 0.53, 95% CI 0.43-0.66), or Medicaid (OR 0.57, 95% CI 0.50-0.65) (all P < 0.001). Patients treated at FP centers were less likely to have comorbidities (OR 0.89, 95% CI 0.82-0.96) and were associated with a longer LOS (0.10, 95% 0.05-0.15, P < 0.001) in nonelderly adult trauma patients. FP TCs were associated with fewer reported complications (OR 0.83, 95% CI 0.74-0.94) and were associated with a higher likelihood of mortality in nonelderly adults (OR 1.70, 95% CI 1.35-2.12, P < 0.001). CONCLUSIONS: Among this cohort of severe International Classification of Diseases-based injury severity score (ICISS) patients, complications were less likely, but LOS and mortality were increased among FP TC patients. FP centers cared for fewer patients who were Black, uninsured, or who were Medicare/Medicaid/noncommercial insurance.


Assuntos
Centros de Traumatologia , Ferimentos e Lesões , Adulto , Idoso , Demografia , Humanos , Escala de Gravidade do Ferimento , Medicare , Propriedade , Estudos Retrospectivos , Estados Unidos/epidemiologia , Ferimentos e Lesões/terapia
2.
Child Care Health Dev ; 41(6): 789-802, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26255643

RESUMO

BACKGROUND: Understanding the impact of effective paediatric adherence promotion interventions on patients, families and the healthcare system is necessary to inform efforts to improve healthcare quality and control costs. Building on previous research suggesting that improving adherence may have far-reaching benefits, the objective of this study was to quantify the impact of effective adherence promotion interventions for children and adolescents with a chronic medical condition on patients, families and the healthcare system. METHODS: Authors systematically reviewed articles indexed in PubMed, PsycINFO and CINAHL to identify randomized controlled trials of paediatric adherence promotion interventions. Interventions that improved paediatric adherence and examined patient-level, family-level or healthcare system-level outcomes in children and adolescents (M age ≤ 18 years) with a chronic medical condition were included. Two authors independently extracted and classified outcome variables as patient-level (quality of life and disease-related activity restrictions), micro-level (family functioning, family conflict, caregiver quality of life, caregiver sleep interruption, caregiver days away from work and patient missed school days) or macro-level variables (emergency department visits, hospitalizations, outpatient visits and urgent care visits). Outcome variables detailed in previously published reviews (i.e. disease severity) were excluded. RESULTS: Twenty studies representing 19 unique samples met inclusion criteria. An additional eight articles representing trials that did not significantly improve adherence were included in post hoc analyses. Compared with control interventions, effective paediatric adherence promotion interventions improved patient quality of life and family-level outcomes and decreased healthcare utilization among children and adolescents with a chronic medical condition. CONCLUSIONS: Interdisciplinary efforts to improve healthcare quality and reduce spending among children and adolescents with a chronic medical condition may be enhanced by incorporating effective paediatric adherence promotion interventions. As relatively few chronic medical conditions were represented in included studies, future research should examine the impact of paediatric adherence promotion interventions in other populations.


Assuntos
Doença Crônica/tratamento farmacológico , Promoção da Saúde/métodos , Adesão à Medicação , Adolescente , Viés , Criança , Humanos , Melhoria de Qualidade , Qualidade de Vida
3.
Int J Syst Evol Microbiol ; 64(Pt 1): 220-227, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24048862

RESUMO

An aerobic, thermophilic, moderately acidophilic non-spore-forming bacterium, strain K22(T), was isolated from geothermally heated soil at Mount Ngauruhoe, New Zealand. On the basis of 16S rRNA gene sequence similarity, K22(T) was shown to belong to subdivision 4 of the phylum Acidobacteria and to be most closely related to 'Candidatus Chloracidobacterium thermophilum' (86 %) and Blastocatella fastidiosa (86 %). Cells stained Gram-negative and were catalase and oxidase-positive. The major fatty acids detected were iso-C15 : 0, iso-C17 : 0, iso-C19 : 0 and iso-C21 : 0 when standard lipid extraction protocols were employed. Analysis of the total cell lipid acid hydrolysate also detected membrane-spanning and ether lipids, which made up approximately 40 % of the total membrane composition. These lipids included dicarboxylic (iso-diabolic) acid and the glyceryl ether of alkyl analogues of iso-C15 : 0 and iso-diabolic acid. The G+C content of the genomic DNA was 59.6 mol% and the primary respiratory quinone was MK-8. Strain K22(T) grew at 50-69 °C with an optimum temperature of 65 °C and at pH 4.1-7.8 with an optimum growth pH of 6.5. NaCl tolerance was up to 1 % (w/v). Cells displayed a chemoheterotrophic and obligately aerobic metabolism. Cells grew on nutrient broth, alginate, arabinose, Casamino acids, glucose, lactate, formate, mannose, sodium alginate, peptone, sucrose, tryptone, xanthan, xylan, xylose and yeast extract. Nitrogen sources included nitrate, ammonium, urea, yeast extract and Casamino acids, but not dinitrogen gas. The distinct phylogenetic position and the phenotypic characteristics separate strain K22(T) from all other members of the class Acidobacteria and indicate that it represents a novel species and genus, for which the name Pyrinomonas methylaliphatogenes gen. nov., sp. nov. is proposed. The type strain of the type species is K22(T) ( = DSM 25857(T) = ICMP 18710(T)).


Assuntos
Acidobacteria/classificação , Temperatura Alta , Filogenia , Microbiologia do Solo , Acidobacteria/genética , Acidobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Nova Zelândia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
4.
J Exp Med ; 144(3): 768-75, 1976 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-182899

RESUMO

Immobilized antigen-antibody complexes are able to inhibit the mitogenic response of murine spleen cells to the B-cell mitogen 8-bromo-3',5'-cyclic guanosine monophosphoric acid. This this inhibition is dependent on intact Fc fragments in the immobilized complexes. Soluble complexes do not mediate this inhibition. When lipopolysaccharide (lps) activation of B cells was studied, it was found that the mitogenic response was inhibited at all times tested between 2 and 7 days of culture. Also, the LPS-induced mitogenesis of nude spleen cells was inhibited by immobilized complexes, indicating that suppressor T cells probably play no significant role in the inhibition. Immobilized complexes inhibit polyclonal antibody responses in a serum-free system and in the presence of normal mouse serum, but are unable to inhibit in the presence of fetal calf serum (FCS). If nu/nu spleen cells are used, however, the FCS does not block the ability of the complexes to inhibit the polyclonal response. It is suggested that that antigen-antibody complexes under appropriate conditions may bind to B lymphocytes via their Fc receptors and trigger a central "off" signal which blocks proliferation and consequently antibody production.


Assuntos
Formação de Anticorpos , Complexo Antígeno-Anticorpo , Linfócitos B/imunologia , Fragmentos Fc das Imunoglobulinas , Animais , Formação de Anticorpos/efeitos dos fármacos , GMP Cíclico/antagonistas & inibidores , Fragmentos Fab das Imunoglobulinas , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitógenos , Solubilidade , Linfócitos T/imunologia
5.
J Exp Med ; 150(3): 597-606, 1979 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-479763

RESUMO

The mechanism by which LPS stimulates an acute phase serum amyloid A (SAA) response in C3H mice has been studied. A factor (SAA inducer) appears in the blood of C3H/HeN (lipopolysaccharide [LPS]-sensitive) mice approximately 1 h after administration of LPS, which, when passively administered, can induce C3H/HeJ mice to produce SAA although they are resistant to the LPS itself. SAA inducer has been detected in the culture medium of LPS treated C3H/HeN macrophages but not spleen cells. Thus, two stages in the induction of the acute phase SAA response are now recognized: a latent period of 2-3 h during which the SAA concentration remains at baseline values and in which SAA inducer appears, and the period of synthesis of SAA which lasts for approoximately 24 h past induction. It is proposed that a macrophage response to LPS is responsible for production of the serum mediator which induces SAA synthesis.


Assuntos
Amiloide/biossíntese , Endotoxinas/farmacologia , Macrófagos/fisiologia , Proteína Amiloide A Sérica/biossíntese , Animais , Quimera , Feminino , Imunização Passiva , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Baço/imunologia , Fatores de Tempo
6.
J Exp Med ; 142(4): 814-26, 1975 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-1185105

RESUMO

Mouse spleen cells, cultured on surfaces coated with antigen-antibody complexes, are inhibited from responding to the B-cell mitogens, lipopolysaccharide, lipid A, Pneumococcal polysaccharide SIII, and poly I:C. The response to the T-cell mitogen, concanavalin A, is also substantially inhibited by immobilized antigen-antibody complexes, but specific inhibition of the response to phytohemagglutinin is minimal. Control experiments showed that immobilized complexes prepared from IgG F(ab')2 fragments and IgA antibodies (both of which fail to bind to Fc receptors when complexed to antigen) did not show significant inhibitory activity when compared with the inhibition observed with complexes prepared from whole IgG. Suspensions of antigen-antibody complexes prepared from the same antigen and intact IgG antibody did not inhibit mitogenesis. None of the mitogens used could be demonstrated to compete with the binding of aggregated immunoglobulin to the B-cell Fc receptor. It appears that the interaction of Fc receptor-bearing lymphocytes and/or macrophages with immobilized complexes prevents lymphocyte activation by mitogens. It is suggested that the mechanism(s) involved may be relevant to antibody feedback control of the humoral immune response.


Assuntos
Complexo Antígeno-Anticorpo , Linfócitos/imunologia , Animais , Sítios de Ligação de Anticorpos , Concanavalina A/farmacologia , Retroalimentação , Imunoglobulina A , Fragmentos Fab das Imunoglobulinas , Fragmentos Fc das Imunoglobulinas , Lectinas/farmacologia , Lipídeos/farmacologia , Lipopolissacarídeos/farmacologia , Linfócitos/efeitos dos fármacos , Camundongos , Mitógenos/farmacologia , Mitose , Poli I-C/farmacologia , Polissacarídeos Bacterianos/farmacologia , Soroalbumina Bovina/farmacologia , Baço/citologia
7.
J Asthma ; 46(8): 835-40, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19863289

RESUMO

OBJECTIVE: The current study investigated whether differences existed in health-related quality of life between individuals who self-identified as having childhood-onset asthma and individuals without a chronic illness. Additionally, the relationship between perceived illness intrusiveness and illness uncertainty to health-related quality of life was explored. METHODS: College undergraduates at least 18 years of age who self-identified as having childhood asthma were randomly matched by age and gender to healthy control participants. Participants completed a demographic form, the Mishel Uncertainty in Illness Scale-Community Form, the Illness Intrusiveness Scale, and the SF-36 Health Survey, a measure of health-related quality of life. RESULTS: Participants with asthma had significantly lower scores on the total and mental health-related quality of life scales than did healthy control subjects. There were no significant differences between self-identified participants with asthma and matched healthy control subjects on physical health-related quality of life scales. Illness intrusiveness was not related to either the physical (e.g., physical functioning, general health) or mental health-related quality of life. Higher levels of illness uncertainty were significantly related to higher levels of mental health-related quality of life (e.g., vitality, mental health). In addition, participants with asthma scored significantly lower than healthy controls on the social functioning and role-emotional subscales. CONCLUSION: The current study adds to the extant literature by examining the relationships between illness intrusiveness, illness uncertainty, and health-related quality of life among a young adult population. College students with asthma appear to be at risk for diminished quality of life compared to a healthy comparison group. Further examination of various domains of health-related quality of life among older adolescents and young adults with childhood asthma is needed.


Assuntos
Asma/fisiopatologia , Asma/psicologia , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Qualidade de Vida , Estudantes , Universidades , Adulto Jovem
9.
J Clin Invest ; 82(5): 1479-88, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3263392

RESUMO

Acylation of cellular proteins with the fatty acids myristate or palmitate represents an important mechanism for the co- or posttranslational modification of proteins. Lipid A, the biologically active component of bacterial endotoxin, exerts a number of biochemical effects on responsive cell types. Evidence is presented that lipid A stimulates the synthesis and subsequent myristyl acylation of intracellular monocyte and glomerular mesangial cell proteins. Two of the myristylated monocyte proteins were identified by specific immunoprecipitation as the 33-kD IL 1 alpha and beta precursors; a similar myristylated protein was found in mesangial cells. The 17-kD secretory form of monocyte IL 1 beta did not contain covalently linked myristate. Myristyl acylation of the IL 1 precursor proteins may facilitate the processing or membrane localization of these proteins, which lack characteristic hydrophobic signal sequences. The acylated 33-kD IL 1 alpha may remain preferentially associated with the membrane in an active form, whereas limited proteolysis may convert the biologically inactive IL 1 beta precursor into the extracellular, nonacylated, active 17-kD protein.


Assuntos
Mesângio Glomerular/metabolismo , Interleucina-1/metabolismo , Monócitos/metabolismo , Ácidos Mirísticos/metabolismo , Precursores de Proteínas/metabolismo , Acilação , Animais , Concentração de Íons de Hidrogênio , Lipídeo A/farmacologia , Masculino , Metionina/metabolismo , Peso Molecular , Ácido Mirístico , Ratos , Ratos Endogâmicos
10.
HERD ; 10(5): 52-63, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28042703

RESUMO

OBJECTIVE: The primary aim of the present study was to compare sleep characteristics pre- and post-move into a state-of-the-art mental health facility, which offered private sleeping quarters. BACKGROUND: Significant evidence points toward sleep disruption among psychiatric inpatients. It is unclear, however, how environmental factors (e.g., dorm-style rooms) impact sleep quality in this population. METHODS: To assess sleep quality, a novel objective technology, actigraphy, was used before and after a facility move. Subjective daily interviews were also administered, along with the Horne-Ostberg Morningness-Eveningness Questionnaire and the Pittsburgh Sleep Quality Index. RESULTS: Actigraphy revealed significant improvements in objective sleep quality following the facility move. Interestingly, subjective report of sleep quality did not correlate with the objective measures. Circadian sleep type appeared to play a role in influencing subjective attitudes toward sleep quality. CONCLUSIONS: Built environment has a significant effect on the sleep quality of psychiatric inpatients. Given well-documented disruptions in sleep quality present among psychiatric patients undergoing hospitalization, design elements like single patient bedrooms are highly desirable.


Assuntos
Transtornos Mentais , Quartos de Pacientes/normas , Sono/fisiologia , Actigrafia , Adulto , Canadá , Ritmo Circadiano , Estudos Transversais , Projeto Arquitetônico Baseado em Evidências , Feminino , Hospitais Psiquiátricos , Humanos , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
11.
Biochim Biophys Acta ; 818(2): 205-10, 1985 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-4027247

RESUMO

We have studied the role of glycolipids in reducing leakage of aqueous-space markers from liposomes, composed primarily of egg phosphatidylcholine, in the presence of human plasma. Liposomes were either small unilamellar (SUV) or large unilamellar (LUV). Leakage of liposome contents as affected by the incorporation into the liposomal bilayer of mono-, di-, or trisialogangliosides (GM, GD, GT) at different molar ratios in the presence or absence of cholesterol was examined. Leakage from liposomes decreased with increasing ganglioside sialic acid. Asialogangliosides had no effect on calcein leakage in the presence of plasma. The stabilizing effect of gangliosides and cholesterol was synergistic, and SUV containing 10 mol% GT and 33 mol% cholesterol had a half-life for leakage of calcein in plasma at 37 degrees C approaching 24 hours. LUV in the presence of plasma retained their contents longer than SUV, and gangliosides had an additional stabilizing effect. Phosphatidylserine and sulfatides were also capable of substituting for gangliosides in stabilizing liposomes to plasma-induced leakage. It appears that gangliosides stabilize liposomes in plasma at least in part through their ability to impart surface negative charge.


Assuntos
Gangliosídeos/metabolismo , Lipossomos/metabolismo , Plasma , Proteínas Sanguíneas/fisiologia , Soluções Tampão , Colesterol/metabolismo , Fluoresceínas/metabolismo , Humanos , Permeabilidade , Temperatura
12.
Biochim Biophys Acta ; 818(1): 81-6, 1985 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-4016115

RESUMO

A two-dimensional thin-layer chromatographic technique has been used to separate and display gangliosides from murine peritoneal macrophages in different functional states. Resident macrophages have a relatively simple ganglioside pattern with about 15 resorcinol-positive spots. Gangliosides from resident cells contained mostly (90%) N-glycolylneuraminic acid. Thioglycolate-elicited and Corynebacterium parvum-activated macrophages have much more complex patterns with about 40 resorcinol-positive spots. Although ganglioside sialic acid content of stimulated macrophages was only slightly higher than that of resident cells, it consisted of nearly equal amounts of N-acetyl- and N-glycolylneuraminic acid. The shift in the ganglioside sialic acid type and the expression of different gangliosides in macrophages upon stimulation may help explain some of the differences in function and responsiveness noted in these macrophage populations.


Assuntos
Gangliosídeos/metabolismo , Ativação de Macrófagos , Macrófagos/fisiologia , Animais , Feminino , Gangliosídeos/isolamento & purificação , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos , Ácido N-Acetilneuramínico , Propionibacterium acnes/imunologia , Ácidos Siálicos/análise , Tioglicolatos/farmacologia
13.
J Leukoc Biol ; 50(4): 393-401, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1919364

RESUMO

Gangliosides have been shown to act as immunoregulatory agents by altering proliferative responses of lymphocytes to both antigens and mitogens. Most early studies have utilized brain gangliosides and have required high concentrations. The role of endogenous gangliosides from macrophages has remained unexplored. In this study, thioglycolate-elicited murine peritoneal macrophage gangliosides were purified and added to cultures of murine lymphocytes. Nanogram amounts caused a profound inhibition of LPS-induced DNA synthesis of splenocytes and of purified B lymphocytes, without demonstrable cellular toxicity. No effect was seen using asialo-GM1. This effect was present across a wide range of lipopolysaccharide (LPS) doses. Nanogram amounts of macrophage gangliosides also inhibited concanavalin A (ConA)-mediated lymphocyte proliferation. Inhibition of LPS-induced mitogenesis was present even if gangliosides were removed from the extracellular environment after 15-60 min of incubation prior to the addition of LPS. This inhibition was reversible with incubation of ganglioside pre-treated lymphocytes in medium containing serum. These inhibitory properties of macrophage gangliosides are distinct from those found in studies using brain gangliosides, and support a potential role for macrophage gangliosides as negative modulators of lymphocyte proliferation.


Assuntos
Gangliosídeos/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Macrófagos/química , Cavidade Peritoneal/citologia , Animais , Células Cultivadas , Concanavalina A , Relação Dose-Resposta a Droga , Feminino , Gangliosídeos/análise , Gangliosídeos/metabolismo , Lipopolissacarídeos , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C3H
14.
J Leukoc Biol ; 40(4): 367-79, 1986 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3462286

RESUMO

We have investigated the ability of gangliosides isolated from murine brain to modulate macrophage metabolism. LPS elicits a profound increase in glucose consumption by cultured resident macrophages. When highly purified mouse brain gangliosides are added to macrophage cultures, a modest inhibition of baseline glucose utilization occurs. Both disialogangliosides and trisialogangliosides mediate this effect. In the absence of serum, these gangliosides may be toxic to cultured macrophages. GT1b is the only brain ganglioside tested that specifically inhibited LPS-induced macrophage metabolism. Sialic acid appears to be a necessary component of the gangliosides, although it is not sufficient to induce inhibition. Asialoganglioside and free sialic acid have no effect on macrophage metabolism in comparison with intact gangliosides. The inhibition of LPS-induced metabolism may be explained by the ability of LPS to form stable molecular complexes with both disialogangliosides and trisialogangliosides. These experiments also suggest that the ganglioside content of macrophages may influence functional responses of macrophages to exogenous stimuli.


Assuntos
Gangliosídeos/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Animais , Química Encefálica , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Interações Medicamentosas , Gangliosídeos/isolamento & purificação , Glucose/metabolismo , Lipopolissacarídeos/antagonistas & inibidores , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos , Ácidos Siálicos/farmacologia
15.
J Leukoc Biol ; 43(5): 436-44, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3131472

RESUMO

We investigated the effect of lipopolysaccharide (LPS) incorporated into phospholipid vesicles (liposomes) on the induction of macrophage-mediated tumor cytotoxicity and tumor necrosis factor (TNF) secretion. The incorporation of Salmonella minnesota rough (Re)-LPS into multilamellar or small unilamellar vesicles (liposomes) resulted in an 100- to 1,000-fold reduction in its potency to activate both the macrophage cell line RAW 264.7 and murine thioglycolate elicited peritoneal macrophages to become cytotoxic for L929 and P815 tumor cells. Liposomal LPS was also a 100- to 1,000-fold less potent inducer of TNF secretion from RAW 264.7 cells. Cytokines secreted by the activated macrophages contributed to the cytotoxic effect on the L929 cells but not the P815 cell line. Human recombinant TNF was not cytotoxic for either cell line but was cytostatic for the L929 cell line. Morphological examination of the cells after uptake of fluorescent, free, and liposomal LPS revealed that both forms were internalized by the endocytic pathway. This, together with the considerably reduced potency of liposomal LPS to induce tumor cytotoxicity and TNF secretion, suggests that the interaction of the hydrophobic part of the lipid A moiety of LPS with the macrophage plasma membrane is needed to optimally activate these cells. Incorporation of LPS into liposomes effectively abrogates this interaction.


Assuntos
Lipopolissacarídeos/farmacologia , Lipossomos , Macrófagos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Animais , Linhagem Celular , Citotoxicidade Imunológica , Fluoresceína-5-Isotiocianato , Fluoresceínas , Ativação de Macrófagos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Microscopia de Fluorescência , Tiocianatos
16.
J Leukoc Biol ; 45(3): 221-30, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2494280

RESUMO

The ganglioside composition of endotoxin-responsive C3H/HeN murine peritoneal macrophages is known to undergo dramatic changes in vivo in response to intraperitoneal lipopolysaccharides (LPS), unlike endotoxin-hyporesponsive C3H/HeJ macrophages. To better investigate the mechanism behind LPS-induced macrophage ganglioside changes, resident C3H/HeN peritoneal macrophages were treated in vitro with 0.1-1.0 micrograms/ml LPS for 6-96 hr, but showed no differences in membrane ganglioside patterns. Coincubation of macrophages with lymphocytes and treating with LPS again elicited no ganglioside changes. In contrast, interferon gamma (IFN-gamma)-primed macrophages showed a dramatic shift in intensity of one ganglioside when treated with LPS in vitro; an additional macrophage ganglioside appeared when IFN-gamma-primed, LPS-treated macrophages were coincubated with lymphocytes. Ganglioside expression induced in vitro still did not approach the complex changes seen in vivo. However, transplanting C3H/HeN macrophages intraperitoneally into C3H/HeJ mice, followed by administration of intraperitoneal LPS, did reveal striking changes in ganglioside expression that resembled the pattern seen in vivo. Thus, LPS alone does not provide the necessary direct signal to promote macrophage ganglioside change even though it alters macrophage function. IFN-gamma appears to be one important mediator; however, complex interactions involving other cytokines or migration of independent populations of mononuclear cells may be required for the full manifestation of LPS-induced ganglioside expression in macrophages.


Assuntos
Gangliosídeos/análise , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Animais , Feminino , Interferon gama/farmacologia , Ativação de Macrófagos , Macrófagos/análise , Macrófagos/transplante , Camundongos , Camundongos Endogâmicos C3H , Ácido N-Acetilneuramínico , Cavidade Peritoneal/citologia , Ácidos Siálicos/análise
17.
J Leukoc Biol ; 44(6): 521-8, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3264007

RESUMO

Gangliosides have been prepared from resting murine thymocytes and splenic T cells. Profoundly different two-dimensional thin layer chromatography (2D TLC) patterns were observed between these two cell types. Thymocytes contained 28-30 discrete gangliosides of which eight represented major gangliosides. Splenic T lymphocytes from both strains had much simpler patterns, with six to seven major gangliosides and 12-13 minor gangliosides. Computerized analysis of the thymocyte ganglioside patterns between LPS-responder C3H/HeN mice and lipopolysaccharide (LPS)-hyporesponsive C3H/HeJ mice revealed no significant difference in the major gangliosides. However, with splenic T cell gangliosides, there is a striking difference in the relative proportion of three homologous gangliosides between the two strains. Consistent with previous observations on macrophage gangliosides, the ratio of N-acetylneuraminic acid-containing ganglioside to N-glycolylneuraminic acid-containing ganglioside was higher in both thymocytes and T-cells from the LPS-responder strain. These results show that sialic acid-containing glycolipids from thymocytes and T lymphocytes between endotoxin responder and hyporesponder strains manifest small but significant changes. These differences are present in unstimulated cell populations and may represent a manifestation of the Lps gene.


Assuntos
Gangliosídeos/análise , Linfócitos T/análise , Animais , Cromatografia em Camada Fina , Feminino , Lipopolissacarídeos/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Ácido N-Acetilneuramínico , Ácidos Siálicos/análise , Especificidade da Espécie
18.
J Leukoc Biol ; 69(6): 969-76, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11404384

RESUMO

Endotoxin-responsive (C3H/HeN) and -hyporesponsive (C3H/HeJ) murine B lymphocytes purified by adherence to anti-immunoglobulin ("antibody panning") possess identical gangliosides but different ganglioside surface accessibilities. We investigated the distribution and surface accessibility of gangliosides of B lymphocytes purified by adherence to plastic ("plastic panning") or by subtraction of non-B-lymphocyte components. As with antibody panning, there were no entirely new or absent gangliosides in plastic-panned or subtraction-purified B lymphocytes of each strain. However, striking changes in relative expression of five gangliosides were detected with each purification protocol. Moreover, five gangliosides of antibody-panned and plastic-panned B lymphocytes but only two gangliosides of subtraction-purified B lymphocytes were inaccessible to surface labeling. Unlike the situation for antibody-panned B lymphocytes, no interstrain (HeN vs. HeJ) surface accessibility differences existed in gangliosides of plastic-panned or subtraction-purified cells. Exposure of subtraction-purified B lymphocytes to anti-immunoglobulin failed to elicit changes in ganglioside expression. Murine B lymphocytes have distinct protocol-dependent differences in glycolipid phenotype which likely denote individual subpopulations.


Assuntos
Subpopulações de Linfócitos B/metabolismo , Separação Celular/métodos , Endotoxemia/imunologia , Endotoxinas/toxicidade , Gangliosídeos/metabolismo , Baço/metabolismo , Animais , Adesão Celular , Cromatografia em Camada Fina , Endotoxemia/genética , Predisposição Genética para Doença , Imunidade Inata , Camundongos , Camundongos Endogâmicos C3H , Plásticos , Receptores de Antígenos de Linfócitos B/análise , Ácidos Siálicos/análise
19.
Mol Immunol ; 22(10): 1169-76, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-4079939

RESUMO

Highly purified preparations of mouse gangliosides have been demonstrated to bind to purified preparations of lipopolysaccharide (LPS). In some instances, the binding has been demonstrated to be dependent upon the presence of sialic acid in the ganglioside preparation. The binding of gangliosides to LPS from the deep rough Salmonella minnesota Re mutant has suggested that the interaction involves the lipid A-2-keto-3-deoxyoctulosanate region of the LPS macromolecule. The interaction between gangliosides and LPS has been demonstrated to result in an abrogation of lipid A dependent activation of the classical pathway of serum complement by Re LPS. Surprisingly, however, the presence of sialic acid containing glycolipids has been shown to enhance significantly the capacity of LPS to initiate activation of the alternative pathway of complement. These data suggest that sialic acid can enhance as well as inhibit the formation of a stable alternative-pathway C3 convertase.


Assuntos
Ativação do Complemento/efeitos dos fármacos , Gangliosídeos/farmacologia , Lipopolissacarídeos/farmacologia , Animais , Via Alternativa do Complemento/efeitos dos fármacos , Via Clássica do Complemento/efeitos dos fármacos , Feminino , Gangliosídeos/metabolismo , Humanos , Lipopolissacarídeos/metabolismo , Masculino , Camundongos , Coelhos
20.
J Endotoxin Res ; 6(1): 25-31, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11061029

RESUMO

Evidence from in vitro experiments and animal and human studies indicate that antibiotic therapy may induce the release of endotoxin from the outer membrane of Gram-negative bacteria. Antibiotics that bind preferentially to penicillin-binding protein-2 (PBP-2)--such as imipenem--are associated with little release of endotoxin, while antibiotics that preferentially bind to PBP-3--such as ceftazidime--are associated with far greater release of endotoxin. We conducted a randomized, multicenter, double-blind study comparing imipenem to ceftazidime in patients with urinary tract infections caused by Gram-negative bacilli associated with signs and symptoms of systemic inflammation. A total of 33 patients were randomized to receive either imipenem (n = 14) or ceftazidime (n = 19) for initial treatment for urosepsis. No differences in plasma endotoxin, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) or urine endotoxin, IL-6 or IL-8 levels were found between the two treatment groups within the first 8 h after antibiotic administration. We conclude that, if differences exist with respect to endotoxin release by these two antimicrobial agents, these differences are not readily demonstrable in this clinical study with carefully defined patients with Gram-negative urinary tract infections.


Assuntos
Antibacterianos/uso terapêutico , Ceftazidima/uso terapêutico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Imipenem/uso terapêutico , Infecções Urinárias/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Citocinas/metabolismo , Método Duplo-Cego , Endotoxinas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sepse/tratamento farmacológico , Sepse/microbiologia , Infecções Urinárias/microbiologia
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