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1.
Eur J Cancer Care (Engl) ; 22(2): 245-52, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23320955

RESUMO

This paper proposes 'QuickPIPER', a 15-item, validated one-dimensional model representing cancer-related fatigue, based on factor analysis testing of the Piper Fatigue Scale-revised (R-PFS). One hundred and eleven breast cancer survivors participated in this prospective, observational study of the QuickPIPER validation. Participants completed the R-PFS and the Profile of Mood States (POMS) Fatigue and Vigor subscales. The questionnaires were tested concurrently before and after a multimodal exercise programme trial. Psychometric characteristics assessed from the sample included internal consistency and factor analysis, concurrent criterion validity and predictive ability. The results shows that the correlation matrix for the QuickPIPER questionnaire was determined as suitable with the Kaiser-Meyer-Oklin values (0.89) and Bartlett's Test of Sphericity (P < 0.001). The total cumulative variance explained was 65.32%. The goodness-of-fit indices of confirmatory factor analysis were satisfactory (normed fit index = 0.91 and comparative fit index = 0.92). Test-retest reliability was very good (r = 0.947, P < 0.001). The QuickPIPER scores correlated with POMS Fatigue (r = 0.800) and POMS Vigor (r = -0.352) subscales. Predictive ability showed that the area under the curves for the screening questionnaires was 0.743 (95% confidence interval 0.579-0.906). The 15-item QuickPIPER possesses similar properties to the 22-item R-PFS and offers the important advantage of brevity.


Assuntos
Neoplasias da Mama/psicologia , Fadiga/psicologia , Psicometria/métodos , Adulto , Idoso , Neoplasias da Mama/complicações , Análise Fatorial , Fadiga/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Inquéritos e Questionários , Sobreviventes/psicologia
2.
Complement Ther Clin Pract ; 18(3): 140-4, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22789787

RESUMO

UNLABELLED: Patient experience of acupuncture at a GP surgery was evaluated over 18 months. Patients were referred for six acupuncture treatments of 45 min by 10 practising GPs. Measure Your Medical Outcome Profile (MYMOP), was completed before the first treatment and at the start of the final consultation. A patient experience survey was completed immediately after the patient's last appointment. RESULTS: A statistically and clinically significant improvement in the mean MYMOP profile score (1.6 SD 1.3, p < 0.0000) (n = 47); reduction in medication usage; a reduction in pain and stress and improved quality of life. CONCLUSIONS: Acupuncture provision was beneficial to patients with predominately chronic conditions. Further studies are needed to assess the cost effectiveness and long term benefit of acupuncture in the NHS.


Assuntos
Terapia por Acupuntura , Medicina Geral , Dor , Satisfação do Paciente , Preparações Farmacêuticas/administração & dosagem , Qualidade de Vida , Estresse Psicológico/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Medicina Estatal , Reino Unido , Adulto Jovem
3.
J Clin Invest ; 90(4): 1600-7, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1383277

RESUMO

Rapid translocation of P-selectin (GMP-140) from cytoplasmic granules to the cell membrane of endothelial cells promotes adhesive interactions with neutrophils which, when activated, damage the endothelium. The role of P-selectin in lung vascular endothelial injury in rats after systemic activation of complement by intravenous infusion of cobra venom factor has been assessed. Within 5-10 min after cobra venom factor infusion, the pulmonary vasculature demonstrated immunohistochemical expression of an epitope that reacts with anti-human P-selectin. Monoclonal antibody to human P-selectin blocked in vitro adherence of rat or human platelets (activated with thrombin) to neutrophils and was demonstrated to react with thrombin-activated rat platelets. The antibody did not react with rat neutrophils. In vivo, the antibody had strongly protective effects against cobra venom factor-induced pulmonary vascular injury as determined by permeability changes and hemorrhage. In parallel, lung myeloperoxidase content was greatly reduced and, by transmission electron microscopy, there was markedly diminished adherence of neutrophils to the pulmonary vascular endothelium and much diminished injury of endothelial cells, as defined by hemorrhage. These data indicate that anti-human P-selectin reacts with a pulmonary vascular antigen in rats and that this antigen is essential for the full expression of lung injury.


Assuntos
Neutrófilos/fisiologia , Glicoproteínas da Membrana de Plaquetas/fisiologia , Pneumonia/etiologia , Doença Aguda , Animais , Anticorpos Monoclonais/imunologia , Venenos Elapídicos/toxicidade , Epitopos , Pulmão/enzimologia , Pulmão/patologia , Masculino , Camundongos , Selectina-P , Peroxidase/análise
4.
Proc Natl Acad Sci U S A ; 88(14): 6224-8, 1991 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-1712483

RESUMO

The leukocyte receptor CD62, which is expressed on activated platelets and endothelial cells, is shown to mediate cell adhesion by binding a sialylated carbohydrate structure, sialyl-Lewis x, found on neutrophils, monocytes, and tumor cells. This structure has previously been identified as the ligand for another member of the LEC-CAM family of cell adhesion molecules, endothelial cell-leukocyte adhesion molecule 1, which also binds neutrophils and monocytes. The results demonstrate that although the two LEC-CAMs differ in their biological activities by their distribution and mode of expression, they are capable of mediating cell adhesion by recognition of the same carbohydrate ligand.


Assuntos
Plaquetas/fisiologia , Moléculas de Adesão Celular/imunologia , Adesão Celular , Endotélio Vascular/fisiologia , Antígenos CD15/imunologia , Neutrófilos/fisiologia , Glicoproteínas da Membrana de Plaquetas/imunologia , Animais , Anticorpos Monoclonais , Antígenos CD/imunologia , Plaquetas/imunologia , Configuração de Carboidratos , Sequência de Carboidratos , Linhagem Celular , Células Cultivadas , Selectina E , Endotélio Vascular/imunologia , Humanos , Ligantes , Lipossomos , Dados de Sequência Molecular , Neutrófilos/imunologia , Selectina-P , Ativação Plaquetária , Receptores Imunológicos/imunologia
5.
Circ Res ; 65(3): 847-57, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2475275

RESUMO

Complement is activated, and C3a and C5a anaphylatoxins are generated during hypersensitivity reactions clinically associated with cardiopulmonary collapse. The administration of C3a or C5a to nonsensitized isolated guinea pig hearts mimics the events caused by antigen challenge of sensitized hearts (i.e., cardiac anaphylaxis) in the absence of complement. Thus, complement-derived anaphylatoxins may participate in immediate hypersensitivity reactions in which the heart is a target organ. To assess the contribution of complement activation and anaphylatoxin generation to cardiac dysfunction, we have elicited anaphylaxis in isolated guinea pig hearts in the presence of complement and found that the ensuing dysfunction is markedly enhanced. This amplification is most likely attributable to anaphylatoxin formation because 1) inactivation of C3 or selective C3 depletion, i.e., the loss of the component responsible for the formation of the anaphylatoxins C3a and C5a, prevents complement-induced exacerbation of cardiac anaphylaxis, whereas reconstitution with C3 and C5, or even only C3, restores it; in fact, the greater the C3 content at the time of antigen challenge, the more intense the anaphylactic crisis; and 2) the severity of cardiac anaphylaxis is markedly reduced by preexposure to C3a, and this reduction is directly related to the dose of C3a injected and to the amount of endogenous cardiac histamine depleted by C3a before antigen challenge. Complement-derived anaphylatoxins appear to promote the same mediator release that has been initiated by the antigen-antibody reaction; thus, complement activation functions as an amplification system in cardiac anaphylaxis.


Assuntos
Anafilaxia , Ativação do Complemento , Coração/fisiopatologia , Miocárdio/imunologia , Anafilatoxinas , Animais , Complemento C3/imunologia , Complemento C3a , Complemento C5/imunologia , Complemento C5a , Circulação Coronária , Cobaias , Liberação de Histamina , Masculino , Contração Miocárdica
6.
J Pharmacol Exp Ther ; 248(3): 1003-9, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2467976

RESUMO

Guinea pig ileum is the classical experimental model for assessing the biological activity of complement-derived anaphylatoxins. Nevertheless, it is still at issue whether C3a-induced ileal contraction is entirely dependent on histamine release. We report that the contraction of the intestinal smooth muscle in response to C3a is characterized by two components, fast and slow, whose incidence and amplitude is strictly dependent on C3a concentration; the larger the concentration of C3a, the greater the incidence and magnitude of the fast component and the less frequent the slow component. The fast and slow components were characterized by a sigmoid and bell-shaped concentration-response curve, respectively. The fast component was associated with the release of endogenous histamine, increased in magnitude with the quantity of histamine released and was prevented by the histamine H1 receptor antagonist pyrilamine. On the contrary, there was no correlation between the quantity of histamine released by C3a and the magnitude of the slow component. Instead, the slow component was associated with the release of PGE2 and was prevented by the cyclooxygenase inhibitor indomethacin. Neither component was affected by the leukotriene receptor antagonist FPL 55712. Our data indicate that C3a-induced ileal contraction is partially histamine dependent in that histamine mediates only the fast component, whereas cyclooxygenase metabolites are responsible for the slow component.


Assuntos
Complemento C3/farmacologia , Histamina/fisiologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Prostaglandinas/fisiologia , Animais , Complemento C3a , Cobaias , Liberação de Histamina , Íleo/efeitos dos fármacos , Íleo/fisiologia , Técnicas In Vitro , Indometacina/farmacologia , Leucotrienos/fisiologia , Masculino
7.
J Pharmacol Exp Ther ; 246(3): 911-6, 1988 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2458450

RESUMO

Activation of the complement system with generation of C3a and C5a anaphylatoxins occurs during immediate hypersensitivity reactions; furthermore, the administration of C3a and/or C5a into isolated hearts causes a dysfunction that closely resembles cardiac anaphylaxis. To determine whether complement is activated and anaphylatoxins are generated in the course of immediate hypersensitivity reactions of the heart, we have challenged presensitized isolated guinea pig atria and papillary muscles with the specific antigen in the presence of a source of complement. We have found that the anaphylactic reaction of these cardiac preparations is characterized by complement activation and C3a generation, as well as by histamine release and positive inotropic and chronotropic effects. The amounts of C3a generated and histamine released directly correlated with the extent of C3 consumption. Furthermore, when C3a and C5a inactivation by serum carboxypeptidase N was prevented by DL-2-mercapto-methyl-3-guanidino-ethylthiopropanoic acid, anaphylactic histamine release was enhanced, and chronotropic and inotropic responses were potentiated and prolonged. Notably, the administration of C3a to nonsensitized guinea pig atria and papillary muscles caused positive chronotropic and inotropic effects, which were associated with histamine release and were antagonized by the H2 receptor blocker cimetidine, thereby mimicking the effects of anaphylaxis. Our findings indicate that complement activation and anaphylatoxin generation are typical of cardiac anaphylaxis and suggest that anaphylatoxins function as mediator-modulators of immediate hypersensitivity reactions of the heart.


Assuntos
Anafilaxia/imunologia , Ativação do Complemento , Complemento C3/metabolismo , Liberação de Histamina , Animais , Cimetidina/farmacologia , Complemento C3a , Cobaias , Frequência Cardíaca , Masculino , Contração Miocárdica
8.
Life Sci ; 40(18): 1799-809, 1987 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-3573979

RESUMO

This is the first report of parallel studies of binding indices and physiological responsiveness of the "Serotonin-two" (5-HT2) receptor on the human platelet membrane. Binding indices were measured by a microassay employing [125I]ILSD as radioligand and ketanserin to define specific binding. A single receptor population was found, characterized by a KD of 1.69 +/- 0.45 nM and Bmax of 14.5 +/- 6.0 pmol/g protein in healthy subjects. Functional responsiveness of the platelet 5-HT2 receptor complex was assessed by measurement of the extent to which serotonin (10uM) augmented platelet aggregation induced by threshold concentrations of adenosine diphosphate (ADP). A statistically significant positive correlation was found between the number of platelet 5-HT2 receptor sites (Bmax) and the magnitude of the serotonin-amplified aggregation response (r = .70, n = 38, p less than 0.001). Assessment of binding indices and physiological responsiveness of the platelet 5-HT2 receptor complex should facilitate study of age, hormonal, disease, and drug effects on 5-HT2 receptor function in human subjects.


Assuntos
Plaquetas/análise , Receptores de Serotonina/análise , Difosfato de Adenosina/farmacologia , Adulto , Fatores Etários , Relação Dose-Resposta a Droga , Feminino , Humanos , Ketanserina/farmacologia , Dietilamida do Ácido Lisérgico/metabolismo , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos
9.
Blood ; 66(4): 926-34, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2994782

RESUMO

The distribution of platelet thrombospondin (TSP), fibrinogen, and glycoproteins IIb-IIIa (GPIIb-IIIa) and GPIb were studied in resting and activated human platelets using frozen thin-section immunoelectron microscopy. In resting platelets, TSP and fibrinogen were found within alpha granules and not on the platelet surface. In unstimulated platelets, GPIIb-IIIa and GPIb were distributed diffusely over the platelet membrane as well as within the body of the platelets. Upon thrombin or A23187 stimulation, TSP, fibrinogen, and GPIIb-IIIa colocalized on the platelet membrane and the canalicular system as well as on pseudopodia and between adherent platelets. GPIb distribution was unchanged by platelet activation. The findings support the hypothesis that a macromolecular complex of TSP-fibrinogen and GPIIb-IIIa forms on the activated platelet membrane.


Assuntos
Plaquetas/ultraestrutura , Fibrinogênio/análise , Glicoproteínas/análise , Receptores de Superfície Celular/análise , Membrana Celular/análise , Humanos , Agregação Plaquetária , Glicoproteínas da Membrana de Plaquetas , Trombospondinas , Distribuição Tecidual
10.
Proc Natl Acad Sci U S A ; 82(3): 886-90, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2579381

RESUMO

The purpose of this investigation was to define the cardiac effects of complement-derived C3a anaphylatoxin, in view of the possibility that cardiac dysfunction may occur as a result of complement activation. Purified human C3a was administered by intracoronary bolus injections into isolated guinea pig hearts. As a function of dose, C3a caused tachycardia, impairment of atrioventricular conduction, left ventricular contractile failure, coronary vasoconstriction, and histamine release. These effects were abolished by cleavage of the COOH-terminal arginine by carboxypeptidase B. The magnitude of C3a-induced tachycardia correlated with the amount of endogenous cardiac histamine released into the coronary effluent. Whereas the tachycardia was markedly reduced by the histamine H2 antagonist cimetidine, the contractile failure and the coronary vasoconstriction caused by C3a were antagonized by the leukotriene antagonist FPL 55712 and by the cyclooxygenase inhibitor indomethacin, respectively. This suggests that histamine, leukotrienes, and vasoactive prostanoates may mediate the various cardiac effects of C3a. Our findings indicate that C3a anaphylatoxin has marked cardiac effects at concentrations that are likely to be attained with a degree of C3 activation commonly seen in various disease states. Thus, our data are compatible with the hypothesis that generation of anaphylatoxins may induce cardiac dysfunction in clinical conditions.


Assuntos
Anafilatoxinas/farmacologia , Complemento C3/farmacologia , Coração/efeitos dos fármacos , Peptídeos/farmacologia , Cromonas/farmacologia , Cimetidina/farmacologia , Complemento C3/análogos & derivados , Complemento C3a , Circulação Coronária/efeitos dos fármacos , Relação Dose-Resposta a Droga , Frequência Cardíaca/efeitos dos fármacos , Liberação de Histamina/efeitos dos fármacos , Humanos , Indometacina/farmacologia , Contração Miocárdica/efeitos dos fármacos , Fatores de Tempo , Vasoconstrição/efeitos dos fármacos
11.
J Exp Med ; 158(2): 603-15, 1983 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-6604123

RESUMO

C3a liberated from C3 by treatment with C3 convertase (or by trypsin) induced aggregation of gel-filtered human platelets and stimulated serotonin release. At concentrations of 10(-10) M to 8 X 10(-12) M, C3a induced aggregation when added alone to platelets. However, at lower concentrations (2 X 10(-12) M) C3a did not aggregate platelets directly but exhibited highly significant synergism (two-way analysis of variance P less than 0.0001) with ADP in mediating platelet aggregation and release of serotonin. Removal of the C-terminus arginine from C3a abolished anaphylotoxin activity but did not affect the platelet-stimulating activity of the peptide. C3a and C3a des-arg were equally reactive in mediating platelet aggregation and release of serotonin. Further C3a and C3a des-arg exhibited synergism with ADP of equal significance in both aggregation and the release reaction. The concentrations of C3a required for the platelet-stimulating activity involve relatively small number of molecules per platelet (4,000-10,000 for the synergistic reaction with ADP). These data suggest the possibility of a C3a (C3a des-arg) receptor on human platelets. This premise is strengthened by the demonstration ultrastructurally of C3a on the platelet membrane subsequent to C3a stimulation.


Assuntos
Plaquetas/metabolismo , Complemento C3/fisiologia , Complemento C5/análogos & derivados , Agregação Plaquetária , Difosfato de Adenosina/fisiologia , Plaquetas/fisiologia , Plaquetas/ultraestrutura , Carboxipeptidase B , Carboxipeptidases/farmacologia , Membrana Celular/ultraestrutura , Cromatografia em Gel , Complemento C3a , Complemento C5/fisiologia , Complemento C5a des-Arginina , Sinergismo Farmacológico , Humanos , Serotonina/sangue , Trombina/farmacologia
12.
J Exp Med ; 154(4): 1058-68, 1981 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-6457076

RESUMO

The topographic relationships of platelet membrane glycoprotein IIb and glycoprotein IIIa have been studied in stimulated and unstimulated human platelets using immunoelectron microscopy. An indirect approach with ferritin-conjugated goat anti-rabbit gamma-globulin was used to localize the rabbit antibody to glycoprotein IIIa. The second ultrastructural label was keyhole limpet hemocyanin conjugated directly to antibody to glycoprotein IIb. Using the double labels, it was demonstrated that glycoprotein IIb and glycoprotein IIIa were distributed randomly in the unstimulated platelet membrane. After platelet stimulation with thrombin, large clusters of glycoprotein IIb-glycoprotein IIIa complexes were formed. No complex formation between glycoprotein Ib and glycoprotein IIb was observed in control experiments. These observations suggest that thrombin stimulation initiates the specific glycoprotein IIb-glycoprotein IIIa macromolecular complex formation on the platelet surface, which may act as the active fibrinogen-binding site required for normal platelet aggregation.


Assuntos
Plaquetas/ultraestrutura , Glicoproteínas/imunologia , Proteínas de Membrana/imunologia , Trombina/farmacologia , Animais , Membrana Celular/análise , Ferritinas/metabolismo , Hemocianinas/metabolismo , Humanos , Glicoproteínas da Membrana de Plaquetas , Coelhos
13.
J Exp Med ; 153(2): 257-68, 1981 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-7241047

RESUMO

Arachidonate-mediated release of 14C serotonin and thromboxane B2 (TXB2) is significantly enhanced in the presence of complement. Only purified complement components C5, C6, C7, C8, and C9 are required for this reactivity. No known activating mechanism of the classical or alternative pathway is required, nor is C3. In the absence of exogenously added complement, platelet membrane-bound complement components play an essential role in modulating arachidonate-mediated serotonin release. Incubation of platelet membranes with arachidonate and C5--C9 led to the production of dimers of the membrane attack complex (C5b--9) on the platelet surface. These macromolecular complexes were eluted from the platelet membrane and were identified physicochemically and morphologically. The possibility arises that C3 in association with C5--C9 is required for mobilization of the arachidonic acid from the phospholipid of the platelet membrane. Once the arachidonic acid is mobilized, C3 is no longer required, C5--C9 being sufficient to modulate this pathway leading to enhanced production of TXB2.


Assuntos
Ácidos Araquidônicos/farmacologia , Plaquetas/metabolismo , Proteínas do Sistema Complemento , Animais , Membrana Celular/imunologia , Complemento C3/imunologia , Complemento C4/imunologia , Complemento C5/metabolismo , Humanos , Coelhos , Serotonina/metabolismo , Albumina Sérica/imunologia , Tromboxano B2/metabolismo
14.
J Sch Health ; 49(8): 466-9, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-258725
15.
J Exp Med ; 150(3): 633-45, 1979 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-479764

RESUMO

Thrombin-mediated platelet aggregation and release is enhanced by the presence of C3, C5, C6, C7, C8, and C9 of human complement. The interaction of thrombin with its receptor on the platelet membrane initiates activation of complement on the platelet surface. Trypsin-mediated platelet function is not enhanced by the addition of complement, probably because trypsin has no receptor on the platelet surface so activation of complement is triggered in the fluid phase and not on the platelet surface. Activation of complement by thrombin led to production of dimers of the C5b-9 complex on the platelet surface. These complexes were eluted from the platelet membrane and were identified physicochemically and morphologically. The mechanism of complement-induced enhancement of platelet function is not clear, however, it probably is mediated via the arachidonic acid transormation pathway because this activity was blocked by known inhibitors of cyclo-oxygenase, namely, aspirin and indomethacin.


Assuntos
Plaquetas/fisiologia , Complemento C5/metabolismo , Complemento C9/metabolismo , Proteínas do Sistema Complemento/fisiologia , Trombina/farmacologia , Antitrombina III/fisiologia , Aspirina/farmacologia , Humanos , Técnicas In Vitro , Agregação Plaquetária/efeitos dos fármacos , Serotonina/metabolismo , Tripsina/farmacologia
16.
Transplantation ; 28(2): 149-53, 1979 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-483361

RESUMO

A modified cytotoxicity assay was adapted from classical erythrocytolytic assays, in which complement components were added in sequence to antibody-sensitized cells. This assay was applied to a model system in which mouse sarcoma cells were sensitized with H-2 alloantibody. The stepwise presentation of complement components combined with the stabilization of C2 by iodine treatment considerably augmented the lytic efficiency of human complement. More generally, the techniques adopted for this study provide a new model for obtaining basic information about selective reaction steps concerned in lysis of nucleated cells by alloantibody and complement. Comparisons of the lysis of sheep erythrocytes by xenoantibody with the lysis of mouse sarcoma cells by H-2 alloantibody, in our assay system with oxidized or untreated human complement, disclosed a difference in the kinetics of C142 formation, manifest in a lag phase and a protracted tmax for the sarcoma cells. These data may suggest that multiple complement-mediated functional lesions are necessary for immune lysis of nucleated cells.


Assuntos
Proteínas do Sistema Complemento/imunologia , Antígenos H-2/imunologia , Isoanticorpos , Sarcoma Experimental/imunologia , Animais , Complemento C1/imunologia , Complemento C4/imunologia , Via Alternativa do Complemento , Testes Imunológicos de Citotoxicidade , Cobaias , Humanos , Coelhos , Ratos
17.
J Natl Med Assoc ; 70(9): 667-70, 1978 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-702600

RESUMO

Total hemolytic complement (CH50) and activation of the alternate mechanism were measured in eight patients before and after splenectomy and compared to similar measurements made in a control group of patients following other abdominal surgery. In the splenectomy group, alternate-pathway-mediated activation of C3 was significantly different from the controls. The mean five-day postsplenectomy value of 16 percent for the immunoelectrophoretic conversion of C3 to C3i was depressed (p<0.001) from the presplenectomy value of 85 percent and five-month postsplenectomy level of 71 percent (p<0.01). The difference between presplenectomy and five-month postsplenectomy values was not significant. Further, activation of C3 in patients five days postsplenectomy was significantly less (p<0.01) than in the five-day postoperative controls. In both the splenectomized patients and control group, five-day postoperative determinations indicated an increase in CH50 values and a decrease in degree of activation of Factor B. The spleen appears to manufacture certain substances required for activation of C3 via the alternate mechanism. That the manufacture is eventually assumed by other immune-competent organs is shown by the eventual increase of activation toward preoperative levels five months postsplenectomy. This defect in C3 activation may account for the tendency of splenectomized patients to have an increased incidence of bacterial infections and sepsis in the postoperative period.


Assuntos
Infecções Bacterianas/etiologia , Ativação do Complemento , Via Alternativa do Complemento , Complicações Pós-Operatórias , Esplenectomia/efeitos adversos , Adulto , Infecções Bacterianas/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
J Natl Med Assoc ; 70(7): 503-6, 1978 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-702579

RESUMO

Total hemolytic complement activity (CH50), immuno-electrophoretic conversion of Factor B (C3PA), and of C3 were studied in 16 patients with sickle cell disease in a steady state, eight patients in crisis, and ten patients with ß-thalassemia major anemia maintained on a constant transfusion regimen. Patients with sickle cell disease in a steady state have moderatley 56 (percent) depressed conversion of Factor B in addition to markedly decreased conversion of C3 in four of ten patients. One of the three sickle cell patients and two of the four thalassemia patients with low C3 conversion levels have died subsequent to the studies. The combination of chronically decreased Factor B conversion in the face of markedly decreased C3 conversion may make these patients occasionally vulnerable to overwhelming infection analagous to the situation seen in postsplenectomy cases.


Assuntos
Anemia Falciforme/imunologia , Ativação do Complemento , Via Alternativa do Complemento , Traço Falciforme/imunologia , Talassemia/imunologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
J Exp Med ; 147(6): 1713-26, 1978 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-681879

RESUMO

Thrombin-mediated platelet membrane-specific uptake of C3 and C5 was demonstrated by radiolabeled components and was visualized electron microscopically utilizing a ferritin marker conjugated to monospecific antibody to each component. The role of complement in thrombin-induced platelet function was determined. Though complement was not essential for thrombin-induced platelet aggregation and release of serotonin, these activities were significantly increased if complement was present. The release of serotonin was found to be a nonlytic process because under the conditions employed, no lactic dehydrogenase was released. The activation of complement was induced by a mechanism which has not been previously described. Thrombin associated with the platelet membrane presumably formed a C3 convertase that entered the known complement sequence at the C3 stage and proceeded to activate the terminal components through the known sequence to C9.


Assuntos
Plaquetas/fisiologia , Proteínas do Sistema Complemento/fisiologia , Trombina/fisiologia , Plaquetas/ultraestrutura , Complemento C3/metabolismo , Complemento C5/metabolismo , Humanos , L-Lactato Desidrogenase/metabolismo , Agregação Plaquetária , Serotonina/metabolismo , Trombina/farmacologia
20.
J Immunol ; 120(3): 879-85, 1978 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-632590

RESUMO

Mouse leukocytes were studied for membrane receptors for the third C component by rosette formation with C coated erythrocytes (EAC). Methods were devised for the preparation of EAC complexes containing either mouse C3b or mouse C3d. EAC 1-3dmo were prepared from EA treated with whole mouse serum while EAC 1-3bmo were produced from EAC 142hu treated with whole mouse serum containing sodium suramin. The specificity of the EAC complexes for mouse leukocytes was confirmed by inhibition experiments using fluid phase human C3d. Low concentrations of fluid phase human C3d inhibited EAC1-3dmo rosettes but failed to inhibit EAC 1-3bmo rosettes. Eight-fold higher concentrations of fluid phase C3d caused partial inhibition of EAC1-3bmo rosette formation with lymphocytes, but not with other types of murine leukocytes. Thus mouse leukocytes apparently contain the same two types of C receptors as do human and guinea pig leukocytes. Mouse CR1 is specific for a non-C3d region of C3b, (possibly analogous to human C3c) whereas mouse CR2 is specific for both C3d and the C3d region of C3b.


Assuntos
Complemento C3 , Leucócitos/imunologia , Animais , Sítios de Ligação , Membrana Celular/imunologia , Complemento C3b , Humanos , Reação de Imunoaderência , Linfócitos/imunologia , Camundongos , Formação de Roseta , Suramina/farmacologia
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