RESUMO
Clinically relevant animal models capable of simulating traumatic hemorrhagic shock are needed. We developed a hemorrhagic shock model with male New Zealand rabbits (2200-2800 g, 60-70 days old) that simulates the pre-hospital and acute care of a penetrating trauma victim in an urban scenario using current resuscitation strategies. A laparotomy was performed to reproduce tissue trauma and an aortic injury was created using a standardized single puncture to the left side of the infrarenal aorta to induce hemorrhagic shock similar to a penetrating mechanism. A 15-min interval was used to simulate the arrival of pre-hospital care. Fluid resuscitation was then applied using two regimens: normotensive resuscitation to achieve baseline mean arterial blood pressure (MAP, 10 animals) and hypotensive resuscitation at 60 percent of baseline MAP (10 animals). Another 10 animals were sham operated. The total time of the experiment was 85 min, reproducing scene, transport and emergency room times. Intra-abdominal blood loss was significantly greater in animals that underwent normotensive resuscitation compared to hypotensive resuscitation (17.1 ± 2.0 vs 8.0 ± 1.5 mL/kg). Antithrombin levels decreased significantly in normotensive resuscitated animals compared to baseline (102 ± 2.0 vs 59 ± 4.1 percent), sham (95 ± 2.8 vs 59 ± 4.1 percent), and hypotensive resuscitated animals (98 ± 7.8 vs 59 ± 4.1 percent). Evidence of re-bleeding was also noted in the normotensive resuscitation group. A hypotensive resuscitation regimen resulted in decreased blood loss in a clinically relevant small animal model capable of reproducing hemorrhagic shock caused by a penetrating mechanism.
Assuntos
Animais , Masculino , Coelhos , Hidratação/métodos , Ressuscitação/métodos , Choque Hemorrágico/terapia , Choque Traumático/terapia , Modelos Animais de Doenças , Hematócrito , Choque Hemorrágico/sangue , Choque Hemorrágico/etiologia , Choque Traumático/sangue , Choque Traumático/complicaçõesRESUMO
Clinically relevant animal models capable of simulating traumatic hemorrhagic shock are needed. We developed a hemorrhagic shock model with male New Zealand rabbits (2200-2800 g, 60-70 days old) that simulates the pre-hospital and acute care of a penetrating trauma victim in an urban scenario using current resuscitation strategies. A laparotomy was performed to reproduce tissue trauma and an aortic injury was created using a standardized single puncture to the left side of the infrarenal aorta to induce hemorrhagic shock similar to a penetrating mechanism. A 15-min interval was used to simulate the arrival of pre-hospital care. Fluid resuscitation was then applied using two regimens: normotensive resuscitation to achieve baseline mean arterial blood pressure (MAP, 10 animals) and hypotensive resuscitation at 60% of baseline MAP (10 animals). Another 10 animals were sham operated. The total time of the experiment was 85 min, reproducing scene, transport and emergency room times. Intra-abdominal blood loss was significantly greater in animals that underwent normotensive resuscitation compared to hypotensive resuscitation (17.1 ± 2.0 vs 8.0 ± 1.5 mL/kg). Antithrombin levels decreased significantly in normotensive resuscitated animals compared to baseline (102 ± 2.0 vs 59 ± 4.1%), sham (95 ± 2.8 vs 59 ± 4.1%), and hypotensive resuscitated animals (98 ± 7.8 vs 59 ± 4.1%). Evidence of re-bleeding was also noted in the normotensive resuscitation group. A hypotensive resuscitation regimen resulted in decreased blood loss in a clinically relevant small animal model capable of reproducing hemorrhagic shock caused by a penetrating mechanism.
Assuntos
Hidratação/métodos , Ressuscitação/métodos , Choque Hemorrágico/terapia , Choque Traumático/terapia , Animais , Modelos Animais de Doenças , Hematócrito , Masculino , Coelhos , Choque Hemorrágico/sangue , Choque Hemorrágico/etiologia , Choque Traumático/sangue , Choque Traumático/complicaçõesRESUMO
BACKGROUND: Synthetic skin analogues or living allogeneic or autologous cells are used as dressings for the care of skin wounds, as well as temporary or permanent substitutes for damaged epithelia. OBJECTIVES: To evaluate if keratinocyte growth on a swine pericardium substrate mimics the natural epithelial layers compared with cultures on allogeneic dermis, which is accepted as having appropriate physical and chemical properties for growth and differentiation. METHODS: Keratinocytes were cultured on a swine pericardium substrate and allogeneic dermis, either submerged or at the air-liquid interface. At 7, 14 and 21 days postseeding the cultures were evaluated by light microscopy after both haematoxylin and eosin staining and immunohistochemistry. RESULTS: Cell-substrate interactions led to growth, stratification and differentiation of cells, with the definition of epithelial layers. The submerged system showed a continuous growth rise on both composites, but this was more prominent with the swine pericardium substrate. An increase in the number of layers at the air-liquid interface with the dermis composites, in contrast to the submerged cultures, occurred only from days 7 to 14. The pattern of keratinocyte growth on swine pericardium substrate was much better in the submerged than in the air-liquid interface cultures. CONCLUSIONS: The results indicate that swine pericardium is a better substrate than allogeneic dermis for keratinocyte cultures in submerged but not in air-liquid interface cultures. Swine pericardium as a substrate opens one more possibility for skin restoration after trauma or burns.
Assuntos
Técnicas de Cultura de Células/métodos , Derme/citologia , Queratinócitos/citologia , Pericárdio , Animais , Processos de Crescimento Celular , Liofilização , Humanos , Microscopia Eletrônica de Transmissão , Pericárdio/anatomia & histologia , Estatística como Assunto , Suínos , Transplante Heterólogo , CicatrizaçãoRESUMO
RATIONALE: Patients with chronic Schistosoma mansoni infection show lower anti-soluble egg antigen (SEA) proliferation responses and higher responses to soluble worm antigen preparation (SWAP). OBJECTIVE: To compare the activation status and proliferation response of peripheral blood mononuclear cells (PBMC) of infected (XTO) and egg-negative individuals (NI) living in the same endemic area. METHODS: XTO (n = 51) and NI individuals from the same geographical area (n = 37) and healthy blood donors (n = 22) were evaluated before and after stimulation with SEA and SWAP. The expression of activation markers (CD4(+) HLADR(+), CD8(high+)HLA-DR(+) and CD8(+) CD28(+)) and proliferation assay was assessed by flow cytometry. FINDINGS: PBMC from infected patients showed lower frequency of CD4(+) but no change in CD8(+) T cells when compared with the healthy donor group. The ratio CD4(+)/CD8(+) was 1.3, 0.6 and 0.5 in healthy donors, infected and non-infected individuals, respectively. The HLA-DR(+) expression on CD8(+) was higher in PBMC from infected and non-infected individuals than from healthy donors, but similar in both total lymphocytes and CD4(+) populations. No intergroup proliferation response differences were observed in CD4(+) and CD8(+) PBMC unstimulated and stimulated with SEA and SWAP. The SEA but not SWAP-stimulated cells showed a decrease in the expression of phosphorylated extracellular signal-regulated kinase (ERK1/2). CONCLUSIONS: XTO and NI individuals living in the same area presented a smaller per cent of CD4(+) and a higher per cent of CD8(+) cells. The activation by either CD8(high+)HLA-DR(+) or CD8(high+)HLA-DR(+)/CD8(+) was enhanced and decreased in XTO and NI by CD8(+) CD28(+) and CD8(+) CD28(+)/CD8(+) when compared with healthy donor. ERK phosphorylation was attenuated in XTO and NI individuals when stimulated with SEA but not SWAP.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Esquistossomose mansoni/imunologia , Subpopulações de Linfócitos T/imunologia , Adolescente , Adulto , Animais , Antígenos de Helmintos/imunologia , Antígenos CD28/imunologia , Citometria de Fluxo , Antígenos HLA-DR/imunologia , Antígenos HLA-DR/metabolismo , Humanos , Pessoa de Meia-Idade , Proteína Quinase 1 Ativada por Mitógeno/imunologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/imunologia , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação , Schistosoma mansoni/imunologia , Transdução de Sinais/imunologiaRESUMO
Today, the quality of a scientific article depends on the periodical in which it is published and on the number of times the article is cited in the literature. In Brazil, the criteria for the evaluation of this scientific production are improving. However, there is still some resistance, with authors arguing that Brazilian publications must be preferentially addressed to the national readers and, therefore, they should ideally be written in Portuguese. In order to determine the kind of scientific journals cited in the reference lists of articles published in medical periodicals edited in Brazil, in the present study we determine the rate of Portuguese/English citations. Three issues of 43 periodicals (19 indexed in SciELO, 10 in PubMed, 10 in LILACS, and 4 in the ISI-Thompson base) of different medical specialties were analyzed, and the number of both Portuguese and English citations in the reference list of each article was recorded. The results showed that in Brazilian-edited journals the mean number of citations/article was 20.9 +/- 6.9 and the percentage of citations of international non-Brazilian periodicals was 86.0 +/- 11.2%. Of the latter, 94.4 +/- 7.0 are indexed by ISI-Thompson. Therefore, we conclude that Brazilian medical scientists cite the international non-Brazilian periodicals more than the national journals, and most of the cited papers are indexed by ISI-Thompson.
Assuntos
Bibliometria , Publicações Periódicas como Assunto/estatística & dados numéricos , Brasil , Bases de Dados Bibliográficas , IdiomaRESUMO
This study was undertaken to evaluate the telomerase activity both in the tumor and in the vaginal margins of radical hysterectomy in patients with squamous cell carcinoma (SCC) of the cervix. Thirty-three patients with SCC of the cervix (study group) and 13 patients with uterine myoma (control group) were prospectively studied. Tissue samples were taken from the tumor or cervix, anterior vaginal margin (AVM), and posterior vaginal margin (PVM). The specimens were analyzed by histopathology, by a telomerase PCR-TRAP-ELISA kit, and by polymerase chain reaction using human papillomavirus (HPV) DNA. The telomerase activity was significantly higher in the tumor than in the benign cervix (P < 0.001). There was no difference in telomerase activity in the AVM and PVM in patients with cervical carcinoma compared to the control group. Telomerase activity was associated with the presence of histologic malignancy in the PVM of patients submitted to radical hysterectomy (P= 0.03). This association was not observed with the presence of HPV in AVM or PVM in the study group. Telomerase activity is a marker of histologic malignancy in patients with SCC of the cervix. There was no association between the telomerase activity and the presence of HPV in vaginal margins of patients submitted to radical hysterectomy.
Assuntos
Carcinoma de Células Escamosas/enzimologia , Histerectomia , Neoplasia Residual/diagnóstico , Papillomaviridae/isolamento & purificação , Telomerase/metabolismo , Neoplasias do Colo do Útero/cirurgia , Vagina/enzimologia , Neoplasias Vaginais/enzimologia , Neoplasias Vaginais/secundário , Adulto , Idoso , Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/virologia , Sondas de DNA de HPV , Feminino , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Vagina/patologia , Vagina/virologia , Neoplasias Vaginais/virologiaRESUMO
The possibility of reducing morbidity associated with surgical dissection while maintaining accurate tumor staging is one of the greatest advantages of the sentinel node approach in surgical oncology. The sentinel node mapping has already proven to be useful in melanoma, breast cancer, and vulvar cancer. We report the first case of sentinel node detection by technetium-labeled radiocolloid in a pregnant woman with cervical cancer. The histologic analysis of the operative specimen showed a poorly differentiated squamous carcinoma with metastasis in the sentinel node and a neoplasic embolus in a blood vessel of the placental bed. The lymphatic mapping and sentinel lymph node detection are feasible during pregnancy.
Assuntos
Carcinoma de Células Escamosas/diagnóstico , Complicações Neoplásicas na Gravidez/diagnóstico , Biópsia de Linfonodo Sentinela , Neoplasias do Colo do Útero/diagnóstico , Aborto Eugênico/métodos , Adulto , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Cuidados Intraoperatórios , Gravidez , Coloide de Enxofre Marcado com Tecnécio Tc 99m , Neoplasias do Colo do Útero/cirurgiaRESUMO
This study was undertaken to evaluate the association between the expression of CD31 in the tumor and the histopathologic findings in patients with carcinoma of the cervix. This study included prospectively 30 women, aged 46.6 +/- 10.7 years, with stage IB squamous cell carcinoma of the cervix submitted to radical hysterectomy from November 2001 to September 2002. Samples from the tumor were taken and immunohistochemically evaluated by a monoclonal antibody for CD31. Clinicopathologic characteristics such as stage, tumor size, grade of differentiation, lymphatic vascular space invasion (LVSI), parametrial involvement, and status of pelvic lymph nodes were also recorded. The clinical stage (FIGO) was IB1 in 22 patients (73.3%) and IB2 in 8 patients (26.7%). The expression of CD31 was significantly associated with tumor size and the presence of LVSI, but not with grade of differentiation and vaginal or parametrial involvement (P= 0.03, P= 0.032, P= 0.352, P= 0.208, and P= 0.242, respectively). On univariate analysis, the presence of pelvic lymph node metastasis was influenced by LVSI (P= 0.003) and CD31 expression (P= 0.032). However, on multivariate analysis, the presence of LVSI (P= 0.007) was the only independent predictor of pelvic lymph node metastasis. The CD31 expression in tumor is significantly associated with LVSI and tumor size in patients with early-stage squamous cell carcinoma of the cervix.
Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Regulação Neoplásica da Expressão Gênica , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Neoplasias do Colo do Útero/metabolismo , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , Diferenciação Celular , Feminino , Humanos , Técnicas Imunoenzimáticas , Linfonodos/metabolismo , Linfonodos/patologia , Metástase Linfática/patologia , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Neoplasias Pélvicas/metabolismo , Neoplasias Pélvicas/secundário , Estudos Prospectivos , Neoplasias do Colo do Útero/patologiaRESUMO
The purpose of the present study was to evaluate the effect of treatment with oxamniquine on the portal pressure of mice infected with Schistosoma mansoni. The animals were infected with 30 cercariae and portal pressure was measured with a polygraph at 70 (acute phase) and 160 (chronic phase) days after infection. On days 70 and 160 two other groups of infected mice were treated with 400 mg/kg of oxamniquine and portal pressure was measured 90 days later (160 and 250 days after infection). A group of uninfected mice was used as control. The measured portal pressures, in mmHg, were: matched uninfected control mice 8.7+/-2.1 and acute phase group, measured at day 70, 13.4+/-3.5. Matched uninfected control 7.5+/-0.6 and chronic phase group, measured at day 160 post-infection, 11.6+/-1.5. Matched uninfected mice 6.9+/-0.9 and chronic phase group, measured at day 250, 10.4+/-1.8. Oxamniquine-treated at day 70 and measured at day 160 7.9+/-0.4; oxamniquine-treated at day 160 and measured at day 250, 7.6+/-1.7. The infection of mice with 30 cercariae of S. mansoni induced portal hypertension, both during the acute and chronic phases and treatment with oxamniquine caused portal pressure to return to normal levels.
Assuntos
Hipertensão Portal/tratamento farmacológico , Oxamniquine/uso terapêutico , Esquistossomose mansoni/tratamento farmacológico , Esquistossomicidas/uso terapêutico , Animais , Hipertensão Portal/etiologia , Masculino , Camundongos , Esquistossomose mansoni/complicaçõesRESUMO
The effects of a fraction (T1) of Tityus serrulatus scorpion venom prepared by gel filtration on gastric emptying and small intestinal transit were investigated in male Wistar rats. Fasted animals were anesthetized with urethane, submitted to tracheal intubation and right jugular vein cannulation. Scorpion toxin (250 microg/kg) or saline was injected iv and 1 h later a bolus of saline (1.0 ml/100 g) labeled with 99m technetium-phytate (10 MBq) was administered by gavage. After 15 min, animals were sacrificed and the radioactivity remaining in the stomach was determined. Intestinal transit was evaluated by instillation of a technetium-labeled saline bolus (1.0 ml) through a cannula previously implanted in the duodenum. After 60 min, the progression of the marker throughout 7 consecutive gut segments was estimated by the geometric center method. Gastric retention of the liquid test meal in rats injected with scorpion toxin (median: 88%; range: 52-95%) was significantly higher (P<0.02) than in controls (54%; 21-76%), an effect which was not modified by gastric secretion blockade with ranitidine. The progression of the isotope marker throughout the small intestine was significantly slower (P<0.05) in rats treated with toxin (1.2; 1.0-2.5) than in control animals (2.3; 1.0-3.2). Inhibition of both gastric emptying and intestinal transit in rats injected with scorpion toxin suggests an increased resistance to aboral flow, which might be caused by abnormal neurotransmitter release or by the local effects of venom on smooth muscle cells.
Assuntos
Esvaziamento Gástrico/efeitos dos fármacos , Trânsito Gastrointestinal/efeitos dos fármacos , Venenos de Escorpião/farmacologia , Animais , Injeções Intraperitoneais , Intestino Delgado/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Estatísticas não ParamétricasRESUMO
The effects of a fraction (T1) of Tityus serrulatus scorpion venom prepared by gel filtration on gastric emptying and small intestinal transit were investigated in male Wistar rats. Fasted animals were anesthetized with urethane, submitted to tracheal intubation and right jugular vein cannulation. Scorpion toxin (250 Ág/kg) or saline was injected iv and 1 h later a bolus of saline (1.0 ml/100 g) labeled with 99m technetium-phytate (10 MBq) was administered by gavage. After 15 min, animals were sacrificed and the radioactivity remaining in the stomach was determined. Intestinal transit was evaluated by instillation of a technetium-labeled saline bolus (1.0 ml) through a cannula previously implanted in the duodenum. After 60 min, the progression of the marker throughout 7 consecutive gut segments was estimated by the geometric center method. Gastric retention of the liquid test meal in rats injected with scorpion toxin (median: 88 percent; range: 52-95 percent) was significantly higher (P<0.02) than in controls (54 percent; 21-76 percent), an effect which was not modified by gastric secretion blockade with ranitidine. The progression of the isotope marker throughout the small intestine was significantly slower (P<0.05) in rats treated with toxin (1.2; 1.0-2.5) than in control animals (2.3; 1.0-3.2). Inhibition of both gastric emptying and intestinal transit in rats injected with scorpion toxin suggests an increased resistance to aboral flow, which might be caused by abnormal neurotransmitter release or by the local effects of venom on smooth muscle cells
Assuntos
Animais , Ratos , Masculino , Esvaziamento Gástrico/efeitos dos fármacos , Trânsito Gastrointestinal/efeitos dos fármacos , Venenos de Escorpião/toxicidade , Injeções Intraperitoneais , Intestino Delgado/efeitos dos fármacos , Ratos Wistar , Estatísticas não ParamétricasRESUMO
In the present work the pH and arterial blood gases were measured in fasted and fed male albino rats, weighing 297 +/- 13 g, anaesthetized with urethane (1.4 g/kg, i.p.) before and after injection of T1 fraction from Titys serrulatus scorpion venom, during 60 min. Arterial blood samples were collected at 0, 5, 15, 30 and 60 min for pH, pCO2, pO2, bicarbonate and base-excess analysis. The data showed that the scorpion toxin induced a continuous drop in the blood pH along the time. Hypercapnia and hypoxemia peaking at 30 min and followed by a recovery towards normal values at 60 min were also observed. A pronounced decrease in the blood bicarbonate levels at 60 min and negative base-excess values along with time were evident at 60 min. The comparisons between fasted and fed animals have shown that in the last group the effects of scorpion toxin on the arterial blood gases were less pronounced. We conclude that T1 fraction of Tityus serrulatus scorpion venom induces in anaesthetized rats an acute respiratory acidosis followed by metabolic acidosis.
Assuntos
Equilíbrio Ácido-Base/efeitos dos fármacos , Venenos de Escorpião/toxicidade , Picada de Aranha/sangue , Anestesia Geral , Animais , Dióxido de Carbono/sangue , Ingestão de Alimentos , Jejum/sangue , Concentração de Íons de Hidrogênio , Masculino , Oxigênio/sangue , Pressão Parcial , Ratos , Ratos Wistar , Mecânica Respiratória/efeitos dos fármacos , Picada de Aranha/fisiopatologiaRESUMO
The aim of this study was to examine the kinetics of neovascularisation of splenic autoimplants into the abdominal cavity after splenectomy in mice. Sixty-eight female Swiss mice were submitted to splenectomy. The spleen from each animal was sliced and the slices were implanted into the abdominal cavity. Groups of animals were killed after 1, 2, 3, 5, 7, 15, 21, 28, 42, 56, 70 and 84 d. Fluorescent polystyrene microspheres were injected via the orbital venous plexus before killing and the splenules were removed 5 min later for light and electron microscopy. Mesenteric blood vessels were injected with coloured latex to study the origin of the nutrient vessels. Three days after the implant the microspheres were observed at the periphery and then migrating to the internal parts of the implant in the subsequent days. The blood supply to the implants originated from branches of the splenic, short gastric, mesenteric and gastroepiploic arteries. It is concluded that revascularisation of splenic autografts proceeds centripetally, starting as early as 3 d after implantation.
Assuntos
Neovascularização Fisiológica , Baço/irrigação sanguínea , Baço/transplante , Animais , Feminino , Camundongos , Camundongos Endogâmicos , Microscopia Eletrônica , Microesferas , Transplante AutólogoRESUMO
Outbred male albino mice normal or infected with 30 cercariae of Schistosoma mansoni (LE strain) were submitted to 65% hepatectomy during the acute (70 days) and chronic phase (160 days) phases of the disease. A group of the infected animals was treated with 400 mg/kg of oxamniquine during the acute phase before hepatectomy. Non-infected, infected and treated but not hepatectomized animals were kept as controls. Hepatic regeneration was evaluated by incorporation of tritiated thymidine, intraperitoneally injected into non-hepatectomized and hepatectomized animals, 24 hours after surgery. The results showed that removal of 65% of the hepatic parenchyma, during the acute phase, led to a statistically significant increase of thymidine incorporation, when compared with the uninfected hepatectomized controls. This phenomenon was not observed at the chronic phase. Treatment with oxamniquine administered during the acute phase led to a decrease in thymidine incorporation rate 160 days after infection (90 days after treatment) and 24 hours after hepatectomy. The data suggest that infection with S. mansoni represents a considerable stimulus for the regenerative capacity of the liver during the acute, but not the chronic phase of disease.
Assuntos
Hepatectomia , Regeneração Hepática , Oxamniquine/uso terapêutico , Schistosoma mansoni , Esquistossomose mansoni/tratamento farmacológico , Esquistossomicidas/uso terapêutico , Doença Aguda , Animais , Doença Crônica , Masculino , Camundongos , Esquistossomose mansoni/induzido quimicamente , Timidina/metabolismoRESUMO
Outbred male albino mice normal or infected with 30 cercariae of Schistosoma mansoni (LE strain) were submitted to 65 percent hepatectomy during the acute (70 days) and chronic phase (160 days) phases of the disease. A group of the infected animals was treated with 400 mg/kg of oxamniquine during the acute phase before hepatectomy. Non-infected, infected and treated but not hepatectomized animals were kept as controls. Hepatic regeneration was evaluated by incorporation of tritiated thymidine, intraperitoneally injected into non-hepatectomized and hepatectomized animals, 24 hours after surgery. The results showed that removal of 65 percent of the hepatic parenchyma, during the acute phase, led to a statistically significant increase of thymidine incorporation, when compared with the uninfected hepatectomized controls. This phenomenon was not observed at the chronic phase. Treatment with oxamniquine administered during the acute phase led to a decrease in thymidine incorporation rate 160 days after infection (90 days after treatment) and 24 hours after hepatectomy. The data suggest that infection with S. mansoni represents a considerable stimulus for the regenerative capacity of the liver during the acute, but not the chronic phase of disease
Assuntos
Camundongos , Animais , Masculino , Hepatectomia , Regeneração Hepática , Oxamniquine/uso terapêutico , Schistosoma mansoni , Esquistossomose mansoni/tratamento farmacológico , Doença Aguda , Doença Crônica , Esquistossomose mansoni/induzido quimicamente , Timidina/metabolismoRESUMO
Seventeen patients stung by Tityus serrulatus scorpion were classified as mild (pain at the site of the sting, n = 6), moderate (local pain and one of the following manifestations: vomiting, psychomotor agitation, prostration, sweating, tachypnea, tachycardia and mild arterial hypertension, n = 10) and severe cases (equal moderate cases plus cardiac failure, pulmonary edema and shock, n = 1). Venous blood was sampled for biochemical and hematological analysis and for IL-1alpha, IL-6, IL-10, TNF-alpha, IFN-gamma and GM-CSF ELISAs at the time of hospital admission, 6 h (moderate and severe cases), and 12, 18, 36 and 72 h (severe case) later. Ten age-matched healthy volunteers were used as control. Increased serum levels of IL-1alpha was noticed in all patients, high levels of IL-6, IFN-gamma and GM-CSF were observed only in a patient with severe envenomation. Our data suggest that a systemic inflammatory response-like syndrome is triggered during severe envenomation caused by T. serrulatus sting and that release of cytokines may be involved in this response.
Assuntos
Citocinas/sangue , Interferons/sangue , Venenos de Escorpião/toxicidade , Fator de Necrose Tumoral alfa/análise , Contagem de Células Sanguíneas , Análise Química do Sangue , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/sangue , Humanos , Interferon gama/sangue , MasculinoRESUMO
The current study has compared the activation status and the expression of the CD28 molecule on circulating CD4+ and CD8+ lymphocytes from patients with different clinical forms of schistosomiasis. The data show that patients with acute schistosomiasis have an increase on the mean percentage of CD4+ HLA-DR+ cells, whereas chronic asymptomatic patients exhibit an increased mean percentage of CD8+ HLA-DR+ cells. Patients with the hepatosplenic disease showed an increase in both CD4+ HLA-DR+ and CD8+ HLA-DR+ cells. Despite the high levels of CD8+ HLA-DR+ cells in hepatosplenic patients, they presented a decreased ratio of CD8+ CD28+/CD8+ cells. These findings of a different percentage of circulating CD8+ CD28+ cells might explain the different in vitro cellular reactivity of asymptomatic and hepatosplenic patients and the defects in the cytokine secretion patterns reported in individuals with hepatosplenic schistosomiasis.
Assuntos
Antígenos CD28/imunologia , Ativação Linfocitária , Esquistossomose mansoni/imunologia , Subpopulações de Linfócitos T/imunologia , Doença Aguda , Adolescente , Adulto , Idoso , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Estudos de Casos e Controles , Criança , Doença Crônica , Citometria de Fluxo , Antígenos HLA-DR/imunologia , Humanos , Hepatopatias Parasitárias/imunologia , Pessoa de Meia-Idade , Esplenopatias/imunologia , Esplenopatias/parasitologiaRESUMO
Scorpion toxin induces gastric secretion of acid and pepsin in rats. These effects seem to be mediated by the release of acetylcholine and histamine. However, the role of gastrin in the scorpion-toxin-induced gastric secretion is unknown. We describe the effects of the T1 fraction purified from Tityus serrulatus scorpion venom on serum and on antral tissue gastrin levels in anaesthetized rats. Gastrin levels in serum and in the antral mucosa were measured before and at intervals 5, 15, 30, 60, 90 up to 120 min after the intravenous injection of saline or the T1 fraction of scorpion venom (0.25 mg/kg) into anaesthetized rats. Antral G-cells were submitted to immunocytochemistry and electron microscopy. The data on gastrin were correlated with the gastric juice volume, and the acid and pepsin output increases induced by toxin. Scorpion toxin induced a significant increase in volume, acid output and pepsin output of gastric juice and gastrin serum levels 15-60 min after injection. Simultaneous measurements of antral gastrin levels did not show significant effects. The number of dense, intermediate and empty granules per microm(2) in the cytoplasm of antral G-cells was not significantly changed 60 min after saline or toxin injection. Scorpion toxin significantly increased serum gastrin; levels in rats.
Assuntos
Ácido Gástrico/metabolismo , Gastrinas/sangue , Pepsina A/metabolismo , Antro Pilórico/ultraestrutura , Venenos de Escorpião/farmacologia , Acetilcolina/metabolismo , Acetilcolina/farmacologia , Anestesia , Animais , Divisão Celular/efeitos dos fármacos , Histamina/farmacologia , Liberação de Histamina/efeitos dos fármacos , Imunoquímica , Masculino , Microscopia Eletrônica , Pepsina A/efeitos dos fármacos , Antro Pilórico/metabolismo , RatosRESUMO
An enzyme presenting kallikrein-like activity (designated sK1) was purified from the supernatant of Schistosoma mansoni adult worm homogenate. The enzyme cleaves bradykinin from purified rat plasma kininogen. Activity was optimal at pH 9.0 and the enzyme showed amidolytic activity, since it hydrolysed the kallikrein synthetic substrate D-Pro-Phe-Arg-p-nitroanilide. The activity of sK1 upon rat plasma kininogen was strongly inhibited by the serine proteinase inhibitors phenylmethanesulfonyl fluoride, aprotinin or soybean trypsin inhibitor, but not by ethylenediaminetetraacetic acid or sodium tetrathionate. The molecular mass of sK1, as determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, was 66 kDa and the pI value, estimated by analytical chromatofocusing, was 4.2. Physical and chemical properties suggest that sK1 is a serine proteinase of the kallikrein family. Evidence is presented which suggests that sK1 is a component of the tegumental surface of the parasite and the levels of its activity in the male adult worm are approximately 21 times higher than those in the female adult worm. The intravenous injection of 3 micrograms of sK1 into an anaesthetized rat induced a drastic reduction in the arterial blood pressure of the animal. This effect lasted for about 1 min, and was followed by a progressive recovery of the arterial pressure. Neither bradycardia nor cardiac arrhythmias were noticed, suggesting a peripheral vasodilation effect. The presence of sK1 on the surface of adult male worms could play an important role in the wandering capacity of coupled worms into the visceral vasculature of the host.
Assuntos
Calicreínas/isolamento & purificação , Schistosoma mansoni/enzimologia , Animais , Aprotinina/química , Pressão Sanguínea/fisiologia , Cromatografia DEAE-Celulose , Cromatografia Líquida de Alta Pressão , Ácido Edético/química , Eletroforese em Gel de Poliacrilamida , Feminino , Concentração de Íons de Hidrogênio , Ponto Isoelétrico , Calicreínas/química , Calicreínas/metabolismo , Cininogênios/sangue , Masculino , Peso Molecular , Fluoreto de Fenilmetilsulfonil/química , Ratos , Ratos Wistar , Schistosoma mansoni/química , Ácido Tetratiônico/química , Inibidores da Tripsina/química , Útero/fisiopatologiaRESUMO
The role of different cytokines in the peripheral blood mononuclear cell (PBMC) proliferative response and in in vitro granuloma formation was evaluated in a cross-sectional study with patients with the different clinical forms and phases of Schistosoma mansoni infection, as well as a group of individuals "naturally" resistant to infection named normal endemic (NE). The blockage of IL-4 and IL-5 using anti-IL-4 and anti-IL-5 antibodies significantly reduced the PBMC proliferative response to soluble egg (SEA) and adult worm (SWAP) antigens in acute (ACT), chronic intestinal (INT) and hepatosplenic (HS) patients. Similar results were obtained in the in vitro granuloma formation. Blockage of IL-10 had no significant effect on either assay using PBMC from ACT or HS. In contrast, the addition of anti-IL-10 antibodies to PBMC cultures from INT patients significantly increased the proliferative response to SEA and SWAP as well as the in vitro granuloma formation. Interestingly, association of anti-IL-4 and anti-IL-10 antibodies did not increase the PBMC proliferative response of these patients, suggesting that IL-10 may act by modulating IL-4 and IL-5 secretion. Addition of recombinant IL-10 decreased the proliferative response to undetectable levels when PBMC from patients with the different clinical forms were used. Analysis of IFN-gamma in the supernatants showed that PBMC from INT patients secreted low levels of IFN-gamma upon antigenic stimulation. In contrast, PBMC from NE secreted high levels of IFN-gamma. These data suggest that IL-10 is an important cytokine in regulating the immune response and possibly controlling morbidity in human schistosomiasis mansoni, and that the production of IFN-gamma may be associated with resistance to infection.