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1.
Cell Microbiol ; 18(1): 66-79, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26153406

RESUMO

Vascular injury is a serious complication of sepsis due to the gram-negative bacterium Neisseria meningitidis. One of the critical early steps in initiating this injury is via the interaction of leucocytes, particularly neutrophils, with adhesion molecules expressed on inflamed endothelium. We have previously demonstrated that both lipopolysaccharide (LPS) and non-LPS components of meningococci can induce very high levels of expression of the vascular endothelial cell adhesion molecule E-selectin, which is critical for early tethering and capture of neutrophils onto endothelium under flow. Using an LPS-deficient strain of meningococcus, we showed that very high levels of expression can be induced in primary endothelial cells, even in the context of weak activation of the major host signal transduction factor [nuclear factor-κB (NF-κB)]. In this study, we show that the particular propensity for N. meningitidis to induce high levels of expression is regulated at a transcriptional level, and demonstrate a significant role for phosphorylation of the ATF2 transcription factor, likely via mitogen-activated protein (MAP) kinases, on the activity of the E-selectin promoter. Furthermore, inhibition of E-selectin expression in response to the lpxA- strain by a p38 inhibitor indicates a significant role of a p38-dependent MAPK signalling pathway in ATF2 activation. Collectively, these data highlight the role that LPS and other bacterial components have in modulating endothelial function and their involvement in the pathogenesis of meningococcal sepsis. Better understanding of these multiple mechanisms induced by complex stimuli such as bacteria, and the specific inflammatory pathways they activate, may lead to improved, focused interventions in both meningococcal and potentially bacterial sepsis more generally.


Assuntos
Fator 2 Ativador da Transcrição/metabolismo , Selectina E/metabolismo , Células Endoteliais/microbiologia , Células Endoteliais/fisiologia , Interações Hospedeiro-Patógeno , Neisseria meningitidis/fisiologia , Células Cultivadas , Endotoxinas/metabolismo , Humanos
2.
Eur J Clin Microbiol Infect Dis ; 31(8): 1847-53, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22222989

RESUMO

Mycobacterium abscessus [M. abscessus (sensu lato) or M. abscessus complex] comprises three closely related species: M. abscessus (sensu stricto), hereafter referred to as M. abscessus, M. bolletii and M. massiliense. We describe here an accurate and robust method for distinguishing M. chelonae from M. abscessus, M. bolletii and M. massiliense, using polymerase chain reaction (PCR) and the sequencing of house-keeping gene targets (hsp65 and rpoB). Sequencing of the sodA gene is of little additional value in discriminating between species, but M. massiliense can be rapidly identified by amplification of the truncated erm(41) gene without the need for amplicon sequencing. We have applied the method to 81 isolates from 40 patients from two hospitals, the majority of whom were cystic fibrosis (CF) patients. Of these patients, 21 had previously been identified as M. chelonae and 59 as M. abscessus complex using commercial line probe assays. We identified these as 46 M. abscessus isolates, 20 M. massiliense isolates, five M. bolletii isolates and nine M. chelonae isolates and confirmed the one M. fortuitum isolate. This is the first study that has identified the individual members of the M. abscessus complex in a UK cohort of mainly CF patients.


Assuntos
Proteínas de Bactérias/genética , Chaperonina 60/genética , RNA Polimerases Dirigidas por DNA/genética , Mycobacterium/classificação , Mycobacterium/genética , Análise de Sequência de DNA/métodos , Adulto , Criança , Pré-Escolar , Fibrose Cística/complicações , Humanos , Mycobacterium/isolamento & purificação , Infecções por Mycobacterium/microbiologia , Reação em Cadeia da Polimerase/métodos , Superóxido Dismutase/genética , Reino Unido
3.
Intensive Care Med ; 32(2): 286-294, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16450100

RESUMO

BACKGROUND: The systemic inflammatory response syndrome (SIRS) may be triggered by endotoxin. Humans have antibodies directed against the core of endotoxin (endotoxin core antibodies, EndoCAb) that appear to be protective following surgery and in sepsis. We hypothesised that children with elevated antibodies to endotoxin core would be less likely to develop SIRS in their initial period on intensive care. Because of the existing literature we defined two sub-groups according to the primary reason for ICU admission: infection and non-infection. METHODS: We recruited 139 consecutive patients admitted to a paediatric intensive care unit (PICU) with more than one organ failure for longer than 12 h as part of another study. Patients were classified on admission to PICU as having an infectious or a non-infections diagnosis. The occurrence of SIRS within 48 h of admission was recorded along with detailed clinical and demographic data, EndoCAb concentration and the potential confounding variables C-reactive protein and mannose-binding lectin. RESULTS: In the 71 patients admitted without infection (primarily post-operative and head injured) IgG EndoCAb was significantly lower in patients who developed SIRS than those who did not (72 vs. 131 MU/ml), independent of potential confounding variables. In patients with infection there was no significant difference in IgG EndoCAb between children developing SIRS and those who did not (111 vs. 80 MU/ml). CONCLUSION: Head injured and post-operative patients admitted to PICU who develop early SIRS have significantly lower serum IgG EndoCAb levels than those who do not.


Assuntos
Estado Terminal , Endotoxemia/complicações , Endotoxemia/imunologia , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Fatores de Risco , Estatísticas não Paramétricas , Síndrome de Resposta Inflamatória Sistêmica/sangue
4.
Clin Exp Immunol ; 135(1): 85-93, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14678268

RESUMO

Binding of host inflammatory cells to the endothelium is a critical contributor to the vascular damage characteristic of severe meningococcal disease and is regulated by endothelial cell adhesion molecules such as ICAM-1, VCAM-1 and CD62E. Intact meningococci induce far higher levels of CD62E than lipopolysaccharide (LPS) alone, whereas LPS is at least as potent as meningococci at inducing both VCAM-1 and ICAM-1 expression. This suggests that meningococci possess additional factors other than LPS present in whole bacteria that result in differential adhesion molecule expression. To investigate this possibility, we studied the capacity of an LPS-deficient isogenic strain of serogroup B Neisseria meningitidis H44/76 (lpxA-) to induce endothelial cell adhesion molecule expression and translocation of the transcription factor NF-kappaB, and compared it to both parent and unencapsulated strains of both B1940 and H44/76 and purified LPS. Although the LPS-deficient isogenic mutant of strain H44/76 was found to be a poor inducer of NF-kappaB, it induced higher levels of CD62E expression than LPS alone. These data provide evidence that intact meningococci induce a range of signals in the endothelium that are distinct from those seen with purified LPS alone and that they occur in a LPS-dependent and LPS-independent manner. These signals may explain the potent effects of N. meningitidis on CD62E expression on vascular endothelium and provide a basis for the complex endothelial dysregulation seen in meningococcal sepsis.


Assuntos
Selectina E/metabolismo , Endotélio Vascular/metabolismo , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Neisseria meningitidis/metabolismo , Células Cultivadas , Ensaio de Desvio de Mobilidade Eletroforética/métodos , Endotélio Vascular/efeitos dos fármacos , Citometria de Fluxo , Humanos , Neisseria meningitidis/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
5.
J Leukoc Biol ; 73(6): 722-30, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12773504

RESUMO

Approximately 25% of polymorphonuclear leukocytes (PMNL) circulate in heterotypic complexes with one or more activated platelets. These platelet-neutrophil complexes (PNC) require platelet CD62P expression for their formation and represent activated subpopulations of both cell types. In this study, we have investigated the presence, time course, and mechanisms of PNC formation in 32 cases of severe pediatric meningococcal disease (MD) requiring intensive care. There were marked early increases in PMNL CD11b/CD18 expression and activation, and reduced CD62L expression compared with intensive care unit control cases. Minimal platelet expression of the active form of alphaIIbbeta3 (GpIIb/IIIa) was seen. PNC were reduced on presentation and fell to very low levels after 24 h. Immunostaining of skin biopsies demonstrated that PNC appear outside the circulation in MD. In vitro studies of anticoagulated whole blood inoculated with Neisseria meningitidis supported these clinical findings with marked increases in PMNL CD11b/CD18 expression and activation but no detectable changes in platelet-activated alphaIIbbeta3 or CD62P expression. In vitro PMNL activation with N. meningitidis (or other agonists) potentiated the formation of PNC in response to platelet activation with adenine diphosphate. Therefore, in severe MD, PMNL activation is likely to promote PNC formation, and we suggest that the reduced levels of PNC seen in established MD reflect rapid loss of PNC from the circulation rather than reduced formation.


Assuntos
Plaquetas/fisiologia , Infecções Meningocócicas/imunologia , Infecções Meningocócicas/fisiopatologia , Ativação de Neutrófilo , Neutrófilos/imunologia , Antígenos CD/análise , Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/análise , Antígenos de Diferenciação Mielomonocítica/imunologia , Biópsia , Sangue , Plaquetas/citologia , Adesão Celular , Moléculas de Adesão Celular/metabolismo , Pré-Escolar , Humanos , Imuno-Histoquímica , Lactente , Recém-Nascido , Integrinas/metabolismo , Cinética , Substâncias Macromoleculares , Infecções Meningocócicas/diagnóstico , Neutrófilos/citologia , Ativação Plaquetária , Contagem de Plaquetas , Transfusão de Plaquetas , Pele/patologia
6.
Infect Immun ; 69(7): 4351-7, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11401973

RESUMO

Interactions between dendritic cells (DCs) and microbial pathogens are fundamental to the generation of innate and adaptive immune responses. Upon stimulation with bacteria or bacterial components such as lipopolysaccharide (LPS), immature DCs undergo a maturation process that involves expression of costimulatory molecules, HLA molecules, and cytokines and chemokines, thus providing critical signals for lymphocyte development and differentiation. In this study, we investigated the response of in vitro-generated human DCs to a serogroup B strain of Neisseria meningitidis compared to an isogenic mutant lpxA strain totally deficient in LPS and purified LPS from the same strain. We show that the parent strain, lpxA mutant, and meningococcal LPS all induce DC maturation as measured by increased surface expression of costimulatory molecules and HLA class I and II molecules. Both the parent and lpxA strains induced production of tumor necrosis factor alpha (TNF-alpha), interleukin-1alpha (IL-1alpha), and IL-6 in DCs, although the parent was the more potent stimulus. In contrast, high-level IL-12 production was only seen with the parent strain. Compared to intact bacteria, purified LPS was a very poor inducer of IL-1alpha, IL-6, and TNF-alpha production and induced no detectable IL-12. Addition of exogenous LPS to the lpxA strain only partially restored cytokine production and did not restore IL-12 production. These data show that non-LPS components of N. meningitidis induce DC maturation, but that LPS in the context of the intact bacterium is required for high-level cytokine production, especially that of IL-12. These findings may be useful in assessing components of N. meningitidis as potential vaccine candidates.


Assuntos
Células Dendríticas/imunologia , Interleucina-12/biossíntese , Lipopolissacarídeos/biossíntese , Neisseria meningitidis/imunologia , Aciltransferases/genética , Citocinas/biossíntese , Células Dendríticas/microbiologia , Humanos , Neisseria meningitidis/genética
7.
Immunology ; 100(4): 441-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10929070

RESUMO

The expression of adhesion molecules on vascular endothelial cells determines the pattern of migration and extravasation of leucocytes in inflammation and immunity. Here we show that costimulation with CD40 ligand (CD40L) and interleukin (IL)-4 (or IL-13) gives rise to a unique pattern of adhesion molecule expression by human umbilical vein endothelial cells (HUVEC). CD40 ligation alone enhanced expression of vascular cell adhesion molecule-1 (VCAM-1), intracellular adhesion molecule-1 (ICAM-1) and E-selectin whereas IL-4 and IL-13 increased expression of VCAM-1 and P-selectin but not ICAM-1 or E-selectin. When IL-4 and CD40L were combined there was an additional increase of both VCAM-1 and P-selectin, but ICAM-1 and E-selectin were both inhibited. The combined effects of IL-4 and CD40L signalling were not the result of altered response kinetics, enhanced sensitivity of the endothelium, or increased expression of CD40 or the IL-4 receptor. The rise in VCAM-1 expression induced by combined IL-4 and CD40L stimulation was slower and more sustained than with tumour necrosis factor-alpha (TNF-alpha) and occurred only on a subset (75-80%) of the endothelial cell population compared to 100% with TNF-alpha. Costimulation with IL-4 and CD40L increased adhesion of T cells and B cells above levels obtained with either signal alone, but decreased adhesion of neutrophils. Furthermore, CD40 and IL-4 synergistically increased IL-6 but decreased IL-8 production by HUVEC. These results show that interactions between IL-4 and CD40 on endothelial cells give rise to specific patterns of adhesion molecule expression and cytokine production that may have important implications for lymphocyte and neutrophil migration and function at sites of inflammation.


Assuntos
Antígenos CD40/imunologia , Endotélio Vascular/imunologia , Interleucina-4/imunologia , Selectina-P/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Ligante de CD40 , Adesão Celular/imunologia , Técnicas de Cultura de Células , Selectina E/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6/biossíntese , Interleucina-8/biossíntese , Ligantes , Linfócitos/imunologia , Glicoproteínas de Membrana/metabolismo , Neutrófilos/imunologia
8.
J Elder Abuse Negl ; 11(4): 23-38, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-21877983

RESUMO

ABSTRACT This article reports the results of a pilot study on the financial abuse of mentally incompetent seniors. The objectives of the study were to: (1) establish the incidence of suspected financial abuse among the clientele of the Office of Public Trustee, Province of Manitoba, (2) identify the characteristics of mentally incompetent older adults most at risk, and (3) identify indicators of financial abuse. Approximately 20% of the cases opened in a one year period were under suspicion of abuse. Findings were consistent with those of other research projects on elder abuse, in general, showing an over-representation of women over the age of eighty as victims of financial abuse. Unpaid personal care home bills when money should have been available was the most common indicator. In addition to providing a list of indicators of financial abuse that are of potential use to professionals, devising prevention programs, practical implications for service providers are presented.

9.
Infect Immun ; 67(11): 5626-33, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10531209

RESUMO

Vascular endothelial injury is responsible for many of the clinical manifestations of severe meningococcal disease. Binding and migration of activated host inflammatory cells is a central process in vascular damage. The expression and function of adhesion molecules regulate interactions between leukocytes and endothelial cells. Little is known about how meningococci directly influence these receptors. In this study we have explored the effect of Neisseria meningitidis on endothelial adhesion molecule expression and found this organism to be a potent inducer of the adhesion molecules CD62E, ICAM-1, and VCAM-1. Exposure of endothelium to a serogroup B strain of Neisseria meningitidis, B1940, and a range of isogenic mutants revealed that lipooligosaccharide (LOS) structure and capsulation influence the expression of adhesion molecules. Following only a brief exposure (15 min) to the bacteria, there were large differences in the capacity of the different mutants to induce vascular cell adhesion molecules, with the unencapsulated and truncated LOS strains being most potent (P < 0.05). Furthermore, the pattern of cell adhesion molecule expression was different with purified endotoxin from that with intact bacteria. Meningococci were more potent stimuli of CD62E expression than was endotoxin, whereas endotoxin was at least as effective as meningococci in inducing ICAM-1 and VCAM-1. The effect of bactericidal/permeability increasing protein (rBPI(21)), an antibacterial molecule with antiendotoxin properties, was also dependent on LOS structure. The strains which possessed a truncated or nonsialylated LOS, whether capsulated or not, were more sensitive to the inhibitory effects of rBPI(21). These findings could have important implications for the use of antiendotoxin therapy in meningococcal disease.


Assuntos
Antibacterianos/farmacologia , Cápsulas Bacterianas/fisiologia , Proteínas Sanguíneas/farmacologia , Moléculas de Adesão Celular/biossíntese , Endotélio Vascular/metabolismo , Lipopolissacarídeos/química , Proteínas de Membrana , Neisseria meningitidis/fisiologia , Peptídeos Catiônicos Antimicrobianos , Células Cultivadas , Selectina E/biossíntese , Humanos , Molécula 1 de Adesão Intercelular/biossíntese , Lipopolissacarídeos/farmacologia , Proteínas Recombinantes/farmacologia , Molécula 1 de Adesão de Célula Vascular/biossíntese
10.
South Med J ; 92(1): 51-4, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9932827

RESUMO

BACKGROUND: In the 1980s, Tennessee ranked among the top 10 states in per capita consumption of several controlled substances. We describe efforts designed to reduce non-criminally motivated misprescribing in Tennessee, present Tennessee's recent Drug Enforcement Administration (DEA) rankings, and suggest how physicians may reduce misprescribing. METHODS: Tennessee's Board of Medical Examiners (BME) consults with Tennessee Physician Health Program (PHP) and refers selected physicians to a continuing medical education (CME) program offered at Vanderbilt University School of Medicine. The BME has also published a clear set of prescribing guidelines. RESULTS: Of more than 160 CME participants, only two have reappeared before the BME for prescribing infractions. Tennessee's overall DEA ranking improved from 7th highest to 17th from 1994 to 1997. CONCLUSIONS: The reasons the rankings improved cannot be established, but the changes occurred at the same time as the BME, PHP, and Vanderbilt CME collaborations. We will continue to promote professional and patient health throughout the region.


Assuntos
Controle de Medicamentos e Entorpecentes , Padrões de Prática Médica , Educação Médica Continuada , Humanos , Guias de Prática Clínica como Assunto , Tennessee
12.
Bull N Y Acad Med ; 71(1): 111-35, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8069272

RESUMO

Fighting Back is a comprehensive substance abuse program operating in 14 communities spread throughout the United States. The Robert Wood Johnson Foundation has committed more than $45 million over a 7-year period to plan and implement innovative, community-wide initiatives in Columbia, SC; Charlotte, NC; Kansas City, Mo; Little Rock, Ark; Northwest New Mexico; Milwaukee, Wis; New Haven, Conn; Newark, NJ; Oakland, Calif; San Antonio, Tex; Santa Barbara, Calif; Vallejo, Calif; Washington, DC; and Worcester, Mass. In this article the work in progress at the end of 18 months of a 5-year implementation program in each site is reported. A Fighting Back National Program Office operates from a base at Vanderbilt University Medical Center in Nashville, Tenn. The senior staff of this office highlights the process that has unfolded to date, describes some of the sources of encouragement, and discusses some of the critical issues and sources of concern. A "Call to Action" on the part of the federal government is included.


Assuntos
Implementação de Plano de Saúde/normas , Apoio ao Planejamento em Saúde , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Adolescente , Serviços de Saúde Comunitária/organização & administração , Feminino , Implementação de Plano de Saúde/organização & administração , Assistência Técnica ao Planejamento em Saúde , Promoção da Saúde/normas , Humanos , Liderança , Masculino , Defesa do Paciente , Desenvolvimento de Programas/normas , Avaliação de Programas e Projetos de Saúde/normas , Saúde Pública/economia , Fatores de Risco , Centros de Tratamento de Abuso de Substâncias/organização & administração , Transtornos Relacionados ao Uso de Substâncias/economia , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Resultado do Tratamento
14.
J Bone Joint Surg Am ; 67(6): 857-64, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-4019533

RESUMO

We performed ninety-six internal-fixation procedures for fracture or non-union of the humeral shaft in eighty-four patients, with a mean follow-up of 32.6 months (range, three months to fourteen years). The primary indications for operative intervention included humeral shaft fracture in a patient with multiple trauma, non-union, inadequate reduction of a humeral shaft fracture by closed methods, pathological humeral-shaft fracture, and progressive radial-nerve palsy. Methods of internal fixation included compression plates and screws and intramedullary Küntscher nails or Rush rods. The use of an AO/ASIF compression plate or interfragmentary lag screws with an AO/ASIF neutralization plate in twenty-seven multiply-injured patients resulted in a union rate of 100 per cent and generally good motion of the shoulder and elbow. Five multiply-injured patients also obtained good results through fixation by a modified Hackethal technique using two Rush rods. The use of intramedullary Küntscher nails resulted in a rate of union of 91 per cent in eleven multiply injured patients. Ten patients with non-union of a humeral shaft fracture had an 80 per cent rate of union with the use of an AO/ASIF compression plate. The use of a Küntscher nail in eleven patients with non-union resulted in a rate of union of only 73 per cent and frequently caused subacromial impingement. Fractures of the humeral shaft that had had an inadequate reduction by closed means or were associated with progressive radial-nerve palsy were best managed by a compression plate or the modified Hackethal technique.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Fixação Intramedular de Fraturas/instrumentação , Fraturas não Consolidadas/complicações , Fraturas do Úmero/cirurgia , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Fraturas não Consolidadas/cirurgia , Humanos , Fraturas do Úmero/complicações , Fraturas do Úmero/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Dispositivos de Fixação Ortopédica , Paralisia/etiologia , Nervo Radial/lesões , Radiografia
15.
Foot Ankle ; 3(5): 254-60, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6862328

RESUMO

A plan is presented which brings together three elements: the clinical stage of disease, the age of the patient, and the treatment regimes available. It is a practical and systematic yet flexible approach to the successful treatment of a given ingrown toenail. A general outline and specific detail of conservative and surgical technique are offered.


Assuntos
Unhas Encravadas/terapia , Dedos do Pé/cirurgia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Tecido de Granulação/cirurgia , Humanos , Pessoa de Meia-Idade , Unhas Encravadas/cirurgia , Cuidados Pré-Operatórios
18.
Phys Ther ; 48(2): 139, 1968 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-5644988

Assuntos
Amputados , Muletas
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