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1.
Mol Biol Rep ; 39(6): 6843-50, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22318548

RESUMO

Detection and follow up of fibrogenesis in chronic hepatitis C (CHC) is mandatory for early treatment and risk stratification. The current study included 120 patients with CHC, of whom 30 had liver cirrhosis (LC) and 30 had hepatocellular carcinoma (HCC). 15 wedge liver biopsies, taken during laparoscopic cholecystectomy, were included as normal controls. Cases were subjected to laboratory investigations, serologic markers for viral hepatitis and assessment of circulating levels of hyaluronic acid (HA) and platelet-derived growth factor (PDGF). Immunohistochemical expression of connective tissue growth factor (CTGF), PDGF and transforming growth factor-ß1 (TGF-ß1) was also carried out. A significant increase (p < 0.01) in serum HA was noticed in CHC, LC and HCC compared to controls. Although, a significant decrease in serum PDGF was detected in CHC and LC compared to controls, HCC values were comparable. A significant up-regulation of CTGF was detected in CHC, LC and HCC (p < 0.01) in contrast to its limited mild expression in normal livers. Intense PDGF positive staining was noticed in CHC, LC and HCC compared to scattered faint expression in controls. The significant expression and marked intensity of PDGF staining matched the progress to tumorigenesis. A positive TGF-ß1 immunostaining was also noticed in CHC, LC and HCC. An intense and extensive cytoplasmic expression of TGF-ß1 was encountered in patients with LC revealing that CTGF, PDGF and TGF-ß1 act synergistically in LC. Data revealed that HA and CTGF may be implicated as important diagnostic parameters for assessment of hepatic fibrosis and PDGF for monitoring malignant transformation in CHC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Matriz Extracelular/metabolismo , Hepatite C Crônica/metabolismo , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/metabolismo , Lesões Pré-Cancerosas/metabolismo , Adulto , Biomarcadores/sangue , Biomarcadores/metabolismo , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Estudos de Casos e Controles , Transformação Celular Neoplásica , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Feminino , Hepatite C Crônica/complicações , Hepatite C Crônica/patologia , Humanos , Ácido Hialurônico/sangue , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Fator de Crescimento Derivado de Plaquetas/metabolismo , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/virologia , Fator de Crescimento Transformador beta1/metabolismo , Adulto Jovem
2.
Parasitol Res ; 99(5): 528-33, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16633832

RESUMO

The present study was designed to prepare monoclonal antibodies (MAbs) against Schistosoma haematobium soluble egg antigen (SEA) with immunodiagnostic potential for urinary schistosomiasis. From a panel of MAbs, a pair of IgG1 MAbs (2D/11C and 10B/2C) specific for S. haematobium SEA was selected. Both MAbs recognized one band with a 42-kDa molecular weight by western blots. The pair of MAbs was employed in sandwich ELISA for the detection of circulating schistosome antigen (CSA), one as antigen-capturing antibody and the other as peroxidase-conjugated antigen-detecting antibody. The lower detection limit of the assay was 1 ng/ml of S. haematobium SEA. The assay was performed on sera of 65 S. haematobium-infected patients, 25 patients infected with other parasites (Fasciola hepatica, Echinococcus granulosus), and 20 noninfected individuals. CSA was demonstrated in 89% of the S. haematobium-infected group. However, CSA was negative in the sera of healthy individuals and patients infected with other parasites, giving an overall specificity of 100% for the CSA assay. A positive correlation (r=0.37, p<0.01) was detected between the number of S. haematobium eggs excreted in 10 ml urine and the CSA level detected in the sera of S. haematobium-infected patients. Our data show that the use of anti-S. haematobium MAbs for the detection of CSA provides a sensitive and specific method for the immunodiagnosis of active S. haematobium-infected patients. Moreover, CSA assay using this anti-S. haematobium MAb/ELISA system was proven to correlate with intensity of infection and hence morbidity assessment.


Assuntos
Anticorpos Monoclonais , Ensaio de Imunoadsorção Enzimática , Esquistossomose Urinária/diagnóstico , Esquistossomose Urinária/parasitologia , Animais , Anticorpos Anti-Helmínticos/imunologia , Anticorpos Monoclonais/imunologia , Antígenos de Helmintos/imunologia , Estudos de Casos e Controles , Humanos , Estágios do Ciclo de Vida , Camundongos , Camundongos Endogâmicos BALB C , Óvulo/imunologia , Schistosoma haematobium/crescimento & desenvolvimento , Schistosoma haematobium/imunologia , Esquistossomose Urinária/sangue , Esquistossomose Urinária/urina , Sensibilidade e Especificidade
3.
Parasitol Res ; 86(1): 74-80, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10669141

RESUMO

A monoclonal antibody (mAb), 2F/11F, raised against Schistosoma haematobium soluble egg antigen (SEA) was found to be nonreactive with S. mansoni SEA or other parasite antigens (Fasciola hepatica, Echinococcus granulosus). This IgG1 mAb recognized a repetitive epitope on S. haematobium SEA in the molecular-weight regions of 70, 42, and 35 kDa. It was employed as both an antigen-capture and a biotinylated detection antibody in a sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of circulating schistosome antigen (CSA) and had a detection limit of <1 ng S. haematobium SEA/ml. CSA levels were measured in serum and urine samples from 116 S. haematobium-infected rural students before therapy and at 4, 8, and 12 weeks after praziquantel treatment. Serum and urine samples from 50 S. mansoni -infected patients, 15 patients harboring other parasites, and 30 noninfected individuals were also assessed. CSA was detected in 90.5% of serum samples and 94% of urine samples from S. haematobium-infected patients. CSA was undetectable in serum from the 15 patients harboring other parasites and in 94% of serum samples and 84% of urine samples from S. mansoni-infected patients. In the S. haematobium-infected group a positive correlation was detected between CSA levels in serum and urine samples and the egg load per 10 ml urine. A significant reduction in CSA levels was detected in serum and urine samples after praziquantel therapy. CSA was undetectable in 87% of serum samples and 81.5% of urine samples from schistosomiasis haematobium patients at 12 weeks post-treatment. These data demonstrate that the use of mAb 2F/11F for detection of CSA provides a sensitive method for the immunodiagnosis and monitoring of cure of schistosomiasis haematobium.


Assuntos
Anticorpos Monoclonais , Schistosoma haematobium/imunologia , Schistosoma haematobium/isolamento & purificação , Esquistossomose Urinária/diagnóstico , Animais , Anticorpos Anti-Helmínticos/biossíntese , Anticorpos Anti-Helmínticos/imunologia , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Antígenos de Helmintos/sangue , Antígenos de Helmintos/imunologia , Antígenos de Helmintos/urina , Biotinilação , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Contagem de Ovos de Parasitas , Praziquantel/uso terapêutico , Schistosoma haematobium/crescimento & desenvolvimento , Schistosoma mansoni/imunologia , Esquistossomose Urinária/tratamento farmacológico , Esquistossomicidas/uso terapêutico
4.
Blood Coagul Fibrinolysis ; 9(2): 189-94, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9622218

RESUMO

The biological activity of blood coagulation factors II, V, VII, VIII, IX, X, XI and XII, fibrinogen and prekallikrein was assessed in 15 healthy subjects and 60 patients with endemic Egyptian hepatosplenomegaly. The degree of liver disease was graded according to the Child-Pugh classification, the intensity of S. mansoni infection was monitored by determination of circulating schistosome immune complexes (CSIC) level using a monoclonal antibody and hemostasis activation was detected by measurement of hemostatic markers D-dimer and prothrombin fragment 1 + 2 (F1+2). Functional activity of antithrombin III, alpha2-antiplasmin and protein C as well as quantitative determination of plasma concentrations of alpha1-antitrypsin, C1 activator inhibitor and alpha2-macroglobulin were also carried out. The progressive deterioration of liver function which matched the severity of the disease and the intensity of schistosomal infection led to a reduction in anticoagulant proteins (decreases in antithrombin III and protein C) resulting in hypercoagulability and thrombin generation (increased F1+2) subsequently followed by consumption (prolongation of coagulation screening tests, thrombocytopenia, hypofibrinogenemia and decreased factor VIII resulting in hypocoagulability and secondary fibrinolysis (increased D-dimer and decreased alpha2-antiplasmin). A significant decline in fibrinogen and factors VII, XII and prekallikrein was detected in bleeders compared with ascitic patients. The decline in factor XII was closely related to CSIC high titers in all disease groups, but was not correlated to D-dimer or F1+2 concentrations. This suggests that circulating schistosome immune complexes may exert an inhibitory effect on contact factor XII which should be taken into account when considering the reasons for schistosomal coagulopathy and bleeding in hepatosplenic schistosomiasis.


Assuntos
Fatores de Coagulação Sanguínea/metabolismo , Hepatopatias Parasitárias/sangue , Falência Hepática/parasitologia , Esquistossomose mansoni/sangue , Esplenopatias/sangue , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Varizes Esofágicas e Gástricas/complicações , Hemorragia Gastrointestinal/etiologia , Humanos , Pessoa de Meia-Idade , Esplenopatias/parasitologia
5.
Haemostasis ; 27(1): 39-48, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9097085

RESUMO

Some platelet alpha-granule contents were assessed in parallel with other markers of hemostatic imbalance in 50 patients with hepatosplenic schistosomiasis (15 patients with compensated hepatosplenomegaly, 15 patients with advanced hepatic fibrosis and ascites and 20 patients during an acute attack of hematemesis from ruptured esophageal varices). Platelet factor 4 (PF4), beta-thromboglobulin (beta-TG), fibronectin (FN), prothrombin fragment 1 + 2, thrombin-antithrombin (TAT) complexes, fibrin degradation products (FbDP) and D-dimer were assessed in schistosomal patients compared to controls (15 healthy subjects). A significant increase in both thrombin (high TAT and prothrombin fragment 1 + 2 levels) and plasmin (high FbDP and D-dimer levels) generation was detected in decompensated patients establishing the presence of a steady state of low-grade disseminated intravascular coagulation, with and without overt bleeding, in these patients. A decrease in plasma FN concentration was found in diseased groups compared to controls. The reduction in plasma levels of FN paralleled the defective liver function and matched the relative decrease in tissue FN in liver specimens of decompensated patients suggesting that FN levels can be used to evaluate the pathological staging of the disease. A significant increase in beta-TG and PF4 levels was noted in decompensated patients with ascites and/or acute hematemesis compared both to controls and compensated patients reflecting platelet alpha-granule release and consequently increased in vivo platelet activation which may initiate and/or perpetuate the pathophysiological mechanisms of the hemostatic imbalance underlying the hemorrhagic diathesis in hepatosplenic schistosomiasis.


Assuntos
Fibronectinas/sangue , Hematemese/sangue , Hepatopatias Parasitárias/sangue , Fator Plaquetário 4/química , Esquistossomose mansoni/sangue , Esplenopatias/sangue , beta-Tromboglobulina/química , Doença Aguda , Adolescente , Adulto , Feminino , Fibronectinas/fisiologia , Hematemese/etiologia , Hematemese/parasitologia , Humanos , Hepatopatias Parasitárias/patologia , Masculino , Pessoa de Meia-Idade , Fator Plaquetário 4/fisiologia , Esquistossomose mansoni/patologia , Esplenopatias/parasitologia , Esplenopatias/patologia , beta-Tromboglobulina/fisiologia
6.
J Clin Pathol ; 49(12): 990-3, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9038736

RESUMO

AIM: To evaluate the nature of accelerated fibrinolysis in hepatosplenic schistosomiasis. METHODS: The biological activity of plasminogen (Plg), plasminogen activators (PA), alpha 2-antiplasmin (alpha 2-AP) and plasminogen activator inhibitor-1 (PAI-1) was determined by photometric analysis in 15 compensated and 35 decompensated patients with endemic Egyptian hepatosplenomegaly. Quantitative measurement of plasma concentrations of tissue t-PA, t-PA-PAI-1 complex, alpha 2-antiplasmin-plasmin complex (alpha 2-APP), fibrinogen degradation products (FbDP), D-dimers (D-D), thrombin-antithrombin complex (TAT) and prothrombin fragment (F 1 + 2) complexes, using double antibody sandwich enzyme linked immunosorbent assays and grading of the degree of hepatic insufficiency according to the Child-Pugh classification, were also carried out. RESULTS: The progressive deterioration of liver function in schistosomal patients, which matched the severity of the disease, led to simultaneous defects in profibrinolytic (decreased Plg and increased PA and t-PA) and antifibrinolytic (decreased alpha 2-AP and PAI-1) factors-the latter defects being the most prominent-resulting in significant generation of plasmin (increased APP complexes) and therefore enhanced fibrinolysis (increased FbDP and D-dimer). The raised concentrations of FbDP, D-D, TAT and F 1 + 2 established its secondary nature. CONCLUSION: These findings suggest that the amount of PAI-1 available to bind and neutralise circulating t-PA may be a critical factor in the progress of hyperfibrinolysis observed in hepatosplenic schistosomiasis, and that the pronounced reduction in its plasma concentration may be regarded as a potential warning indicator of haemostatic imbalance in decompensated schistosomal patients at high risk of variceal bleeding.


Assuntos
Fibrina/metabolismo , Fibrinólise/fisiologia , Hepatopatias Parasitárias/metabolismo , Esquistossomose mansoni/metabolismo , Adolescente , Adulto , Ascite/metabolismo , Ascite/fisiopatologia , Feminino , Fibrinolisina/metabolismo , Hematemese/metabolismo , Hematemese/fisiopatologia , Hepatite Viral Humana/complicações , Hepatite Viral Humana/metabolismo , Hepatite Viral Humana/fisiopatologia , Humanos , Hepatopatias Parasitárias/complicações , Hepatopatias Parasitárias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Plasminogênio/metabolismo , Esquistossomose mansoni/complicações , Esquistossomose mansoni/fisiopatologia , Índice de Gravidade de Doença
7.
J Egypt Soc Parasitol ; 23(1): 255-61, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8482873

RESUMO

A Ficoll-Hypaque gradient centrifugation technique was used for isolation and concentration of microfilariae from peripheral blood of 30 subjects with clinically and parasitologically diagnosed Wuchereria bancrofti infections. 86% of the microfilariae were found in the Ficoll-Hypaque layer. None were detected in the plasma, leucocyte layer or lower erythrocyte layer. 14% of microfilariae were identified on the top part of the erythrocyte layer. A 35 fold concentration and 88% quantitative recovery of parasites was achieved by conventional centrifugation of microfilariae-rich Ficoll-Hypaque layer. Following the centrifugation procedures, living motile microfilariae were separated. These results indicate that Ficoll-Hypaque centrifugation technique could be an effective method for the detection of low levels of microfilaraemia, and for obtaining relatively pure suspensions of living microfilariae for metabolic studies, production of antigen-rich excretory-secretory products and antigen analysis.


Assuntos
Filariose Linfática/sangue , Wuchereria bancrofti/isolamento & purificação , Animais , Centrifugação com Gradiente de Concentração , Humanos , Microfilárias/isolamento & purificação
8.
J Egypt Soc Parasitol ; 23(1): 277-88, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8482876

RESUMO

Circulating antifilarial IgM and IgG antibodies were assessed by indirect ELISA in 184 serum specimens from 80 patients with clinically and parasitologically diagnosed filarial infections (20 with acute filariasis 40 with chronic filariasis & 20 asymptomatic microfilaraemic subjects), 64 individuals with other parasitic infections, 20 parasitologically-free subjects from filariasis endemic areas and 20 normal healthy controls. A soluble surface membrane extract from Dirofilaria immitis worms was used as the antigen. Using a single serum dilution of 1:128 and optical densities (OD) at 492 nm, the respective cut off values for IgM and IgG were found to be 0.24 and 0.22. All healthy non-endemic controls were seronegative by IgM and IgG ELISAs. The highest antifilarial IgM OD492 values were obtained in 20 patients with acute filariasis (95% sensitivity), while the highest antifilarial IgG OD492 values were observed n 40 patients with chronic filariaisis (97.5% sensitivity). Asymptomatic microfilaraemic subjects gave IgM and IgG OD492 values which were significantly lower than those of other forms of clinical disease and endemic control subjects. The antifilarial IgM and IgG respective sensitivities in asymptomatic subjects were 75% and 70%. Endemic controls had positive antifilarial IgM (65%) and IgG (75%) levels. Of 64 subjects with other parasites only one with Ancylostoma duodenale had positive IgM level (98.4% specificity); while 9 patients with nematodal infections mainly had false positive antifilarial IgG antibody levels (85.9% specificity). These results suggest that measuring circulating antifilarial IgM antibody level may have some diagnostic advantage over measuring IgG antibody level for the detection of active filarial infection and consequently better management of the disease.


Assuntos
Filariose Linfática/diagnóstico , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Wuchereria bancrofti/imunologia , Doença Aguda , Adolescente , Adulto , Idoso , Animais , Anticorpos Anti-Helmínticos/sangue , Criança , Pré-Escolar , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Parasitol Res ; 73(4): 334-40, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3112769

RESUMO

The lymphoproliferative blastogenic responses to mitogens, PHA and Con A, and to schistosome-derived antigens. S. mansoni worm and egg, were tested in 35 schistosomal patients and 10 healthy controls. Of the former group, 18 patients had intestinal mansoniasis and 17 had mansoniasis with hepatosplenomegaly. The test was repeated 2 weeks and 1 and 2 months after treatment with praziquantel. The delayed intradermal test for schistosomiasis was performed on 25 of the schistosomal patients and was repeated 1 month after treatment. Statistical analysis of results of lymphoproliferative blastogenic responses showed no significant differences between the control and the two schistosomal groups in response to mitogens. The group with intestinal mansoniasis responded significantly to both schistosomal antigens, compared to the control and hepatosplenic groups. Their proliferative responses showed a significant rise 2 weeks after treatment, then a gradual drop at 1 and 2 month intervals. The hepatosplenic group responded significantly to worm antigen before treatment; their proliferative responses to both schistosomal antigens showed a significant rise 2 weeks after treatment and remained raised thereafter. No relationship was established between either of the two schistosomal groups for age, intensity of infection or positive delayed intradermal reaction.


Assuntos
Ativação Linfocitária/efeitos dos fármacos , Praziquantel/uso terapêutico , Schistosoma mansoni/imunologia , Esquistossomose mansoni/imunologia , Adolescente , Adulto , Antígenos de Helmintos/imunologia , Criança , Concanavalina A , Humanos , Imunidade Celular/efeitos dos fármacos , Pessoa de Meia-Idade , Fito-Hemaglutininas , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/tratamento farmacológico
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