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1.
Eur J Sport Sci ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978338

RESUMO

Pregnancy and childbirth involve substantial physical, physiological and psychological changes. As such, postpartum rugby players should be supported and appropriately prepared to return to the demands of rugby alongside the additional demands of motherhood. This review aims to discuss specific perinatal considerations that inform a rugby player's readiness to return-to-sport postpartum and present an approach to rehabilitation. Before engaging in full rugby training and matchplay, postpartum players should have progressed through the initial phases of rehabilitation and graded sports-specific training to prepare them for the loads they will be exposed to. Additional rehabilitation considerations include minimising deconditioning during pregnancy; medical concerns; the abdominal wall; the pelvic floor; perinatal breast changes, breastfeeding and risk of contact breast injury; body mass; nutritional requirements; hormonal considerations; athlete identity and psychological considerations; joining team training; return to contact and tackle training; evaluating player load tolerance and future research, policy and surveillance needs. A whole-systems, biopsychosocial approach following an evidence informed return-to-sport framework is recommended when rehabilitating postpartum rugby players. Health and exercise professionals are encouraged to use the perinatal-specific recommendations in this review to guide the development of postpartum rehabilitation protocols and resources.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34500309

RESUMO

Lipid bioactivity is a result of direct action and the action of lipid mediators including oxylipins, endocannabinoids, bile acids and steroids. Understanding the factors contributing to biological variation in lipid mediators may inform future approaches to understand and treat complex metabolic diseases. This research aims to determine the contribution of genetic and environmental influences on lipid mediators involved in the regulation of inflammation and energy metabolism. This study recruited 138 monozygotic (MZ) and dizygotic (DZ) twins aged 18-65 years and measured serum oxylipins, endocannabinoids, bile acids and steroids using liquid chromatography mass-spectrometry (LC-MS). In this classic twin design, the similarities and differences between MZ and DZ twins are modelled to estimate the contribution of genetic and environmental influences to variation in lipid mediators. Heritable lipid mediators included the 12-lipoxygenase products 12-hydroxyeicosatetraenoic acid [0.70 (95% CI: 0.12,0.82)], 12-hydroxyeicosatetraenoic acid [0.73 (95% CI: 0.30,0.83)] and 14­hydroxy-docosahexaenoic acid [0.51 (95% CI: 0.07,0.71)], along with the endocannabinoid docosahexaenoy-lethanolamide [0.52 (95% CI: 0.15,0.72)]. For others such as 13-hydroxyoctadecatrienoic acid and lithocholic acid the contribution of environment to variation was stronger. With increased understanding of lipid mediator functions in health, it is important to understand the factors contributing to their variance. This study provides a comprehensive analysis of lipid mediators and extends pre-existing knowledge of the genetic and environmental influences on the human lipidome.


Assuntos
Ácidos e Sais Biliares/sangue , Endocanabinoides/sangue , Ácidos Graxos Ômega-3/sangue , Metabolismo dos Lipídeos/genética , Oxilipinas/sangue , Esteroides/sangue , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/sangue , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/genética , Adolescente , Adulto , Idoso , Ácidos e Sais Biliares/genética , Desidroepiandrosterona/sangue , Desidroepiandrosterona/genética , Ácidos Docosa-Hexaenoicos/sangue , Ácidos Docosa-Hexaenoicos/genética , Ácido Eicosapentaenoico/análogos & derivados , Ácido Eicosapentaenoico/sangue , Ácido Eicosapentaenoico/genética , Endocanabinoides/genética , Ácidos Graxos Ômega-3/genética , Feminino , Interação Gene-Ambiente , Humanos , Masculino , Pessoa de Meia-Idade , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Adulto Jovem
4.
Nutr Metab Cardiovasc Dis ; 24(9): 996-1003, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24875672

RESUMO

BACKGROUND AND AIMS: Consumption of foods that modulate inflammatory stress in genetically-prone individuals may influence development of cardiometabolic diseases. Isoflavones in soy-derived foods function as phytoestrogens, have antioxidant and anti-inflammatory activity, inhibit protein-tyrosine kinase activity, and may be atheroprotective. We examined the relationship between soy food consumption and inflammatory responses to endotoxemia, postprandial responses to oral lipid tolerance test (OLTT), and insulin sensitivity from frequently sampled intravenous tolerance tests (FSIGTT). METHODS AND RESULTS: We administered low-dose endotoxin (LPS 1 ng/kg) to induce transient endotoxemia in young, healthy volunteers (N = 215) of African (AA), and European (EA) ancestry as part of the GENE Study. We further supported these findings in two independent samples: the MECHE Study and NHANES. Soy food consumption was a significant predictor of peak cytokine response following LPS. Individuals with moderate-high (>1.48 mg/day, N = 65) vs. low-no (<1.48 mg/day, N = 150) isoflavone consumption had significantly higher tumor necrosis factor alpha (TNFα) post-LPS (AUC, P = 0.009). Further, high-isoflavone consumers were protected against inflammation-induced decline in insulin sensitivity (SI) in GENE. We observed significant differences by soy consumption in the interferon gamma (IFNγ) response to OLTT, and the insulin response to OGTT in MECHE, as well as significantly lower fasting insulin, and 2-hour glucose post-OGTT in EA NHANES subjects. CONCLUSION: We demonstrate that soy consumption may influence inflammatory and metabolic responses. In research of nutritional exposures, measuring evoked phenotypes may be more informative than describing resting characteristics. The GENE Study was registered under NCT00953667 and the MECHE Study under NCT01172951, both at clinicaltrials.gov.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Inflamação/prevenção & controle , Isoflavonas/administração & dosagem , Adolescente , Adulto , Negro ou Afro-Americano , Anti-Inflamatórios/administração & dosagem , Antioxidantes/administração & dosagem , Glicemia/metabolismo , Índice de Massa Corporal , Feminino , Voluntários Saudáveis , Homeostase/efeitos dos fármacos , Humanos , Resistência à Insulina , Modelos Lineares , Lipopolissacarídeos/administração & dosagem , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Fitoestrógenos/administração & dosagem , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Ensaios Clínicos Controlados Aleatórios como Assunto , Alimentos de Soja/análise , Fator de Necrose Tumoral alfa/metabolismo , População Branca , Adulto Jovem
5.
Br J Radiol ; 81(963): 252-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18180262

RESUMO

Hypovolaemic shock is an infrequently encountered entity found on CT of victims of severe trauma. Early abdominal and pelvic CT can show diffuse abnormalities owing to hypovolaemia that may alert radiologists to the presence of hypovolaemic shock. In this pictorial review, we present the imaging findings of hypovolaemic shock, as seen on CT of the abdomen. A spectrum of vascular and visceral CT signs is described. Vascular signs include diminished inferior vena cava diameter, diminished aortic diameter and abnormal vascular enhancement. Hollow visceral abnormalities include diffuse increased mucosal enhancement of both the small and large bowel, diffuse thickening of the small bowel wall, and small bowel dilatation. Solid visceral abnormalities include both decreased and increased end organ enhancement. This report should increase radiologists' awareness of the CT manifestations of hypovolaemic shock.


Assuntos
Traumatismos Abdominais/diagnóstico por imagem , Hipovolemia/diagnóstico por imagem , Radiografia Abdominal , Choque/diagnóstico por imagem , Traumatismos Abdominais/complicações , Adulto , Aorta Abdominal/diagnóstico por imagem , Feminino , Humanos , Hipovolemia/etiologia , Masculino , Pessoa de Meia-Idade , Choque/etiologia , Tomografia Computadorizada por Raios X , Veia Cava Inferior/diagnóstico por imagem , Vísceras/diagnóstico por imagem
6.
J Helminthol ; 81(1): 93-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17381874

RESUMO

Proteinases released during the in vitro maintenance of asynchronous cultures of the free-living nematode Caenorhabditis elegans were characterized on the basis of subunit composition, fluorogenic substrate specificity, inhibitor sensitivity and pH optima. Cysteine proteinases are present in the excretory-secretory products (ESP) as indicated by the hydrolysis of cathepsin fluorogenic substrates and confirmed by immunoblotting. Serine proteinases were predominant as indicated by substrate gel analysis and inhibitor studies. The presence of metallo-proteinases was also indicated by inhibitor studies. The optimal pH value for cysteine proteinases was 5.5, while serine proteinases were optimal at pH 8.0. As a control, cultures of Escherichia coli, the diet of C. elegans, were extracted separately and gave no evidence of overlap with C. elegans ESP. Cross reactivity between the ESP of C. elegans and antibodies raised against the ESP of the equine parasite Strongylus vulgaris indicated antigenic relatedness of a proteic epitope. This is the first study to characterize the ESP of C. elegans and to display its relatedness with that of S. vulgaris.


Assuntos
Proteínas de Caenorhabditis elegans/análise , Caenorhabditis elegans , Peptídeo Hidrolases/análise , Animais , Técnicas Imunológicas
7.
Diabet Med ; 23(4): 436-40, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16620274

RESUMO

BACKGROUND: The importance of adipose tissue in metabolism, as a target for insulin action and a secretor of metabolic regulatory proteins, is increasingly recognized. Lipodystrophic conditions are often associated with significant insulin resistance. The commonest acquired form occurs with highly active antiretroviral therapy (HAART) for human immunodeficiency virus infection. Other medical conditions and drugs also have the potential to cause chronic subcutaneous fat damage. CASE REPORT: We describe an unfamiliar partial lipodystrophy in a young woman, associated with markedly insulin-resistant diabetes, acquired following allogeneic bone marrow transplantation for childhood leukaemia complicated by late sclerodermatous chronic graft vs. host disease (GVHD). Clinical examination revealed scarring and lipodystrophy affecting mainly legs, thighs, buttocks and forearms but sparing her face, neck and thorax. Her serum adiponectin level was markedly reduced. CONCLUSIONS: However, although thiazolidinediones lower insulin resistance and increase subcutaneous peripheral fat in Type 2 diabetes, pioglitazone treatment had little effect on either serum adiponectin, glycaemic control or the lipoatrophy. In this case, effective glycaemic control was best achieved using a combination of metformin and highly concentrated soluble insulin injections.


Assuntos
Diabetes Mellitus Tipo 2/etiologia , Doença Enxerto-Hospedeiro , Lipodistrofia/etiologia , Esclerodermia Localizada/etiologia , Adolescente , Transplante de Medula Óssea , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Metformina/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Esclerodermia Localizada/tratamento farmacológico , Transplante Homólogo
8.
Anticancer Res ; 25(6B): 4255-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16309225

RESUMO

Our previous studies on active constituents of Nigella sativa have indicated that cell death induced by thymoquinone and alpha-hederin was dose- and time-dependent, in a range of four cancer cell lines. Both compounds elicited necrosis and apoptosis with a higher incidence of the latter induced by thymoquinone. As HEp-2 human laryngeal carcinoma cells were the most susceptible, we sought to better understand the mechanisms involved by using buthionine sulfoximine (BSO), a selective inhibitor of glutathione (GSH) synthesis, to determine the importance of GSH in the apoptosis elicited, using cisplatin as internal standard. BSO significantly enhanced alpha-hederin- and cisplatin- mediated toxicity as assessed by the MIT assay, without changes in apoptosis or necrosis levels. Although the MTI assay did not indicate BSO potentiation of thymoquinone, apoptosis levels were significantly enhanced following this combination, without changes in necrosis. Thymoquinone and cisplatin significantly decreased GSH levels in a dose-dependent manner, with BSO pre-treatment synergistically depleting GSH levels in only thymoquinone- treated cells. As the caspase 3 inhibitor, Z-DEVD-fmk significantly decreased thymoquinone- and cisplatin-induced apoptosis, GSH depletion and caspase 3-activation mediate thymoquinone-induced apoptosis, in this cell line.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Benzoquinonas/farmacologia , Butionina Sulfoximina/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Laríngeas/tratamento farmacológico , Nigella sativa/química , Ácido Oleanólico/análogos & derivados , Saponinas/farmacologia , Apoptose/efeitos dos fármacos , Benzoquinonas/administração & dosagem , Butionina Sulfoximina/administração & dosagem , Caspase 3 , Inibidores de Caspase , Caspases/metabolismo , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , Cisplatino/farmacologia , Sinergismo Farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Ativação Enzimática , Glutationa/metabolismo , Humanos , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/patologia , Necrose , Ácido Oleanólico/administração & dosagem , Ácido Oleanólico/farmacologia , Saponinas/administração & dosagem
9.
Anticancer Res ; 25(3B): 2199-204, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16158964

RESUMO

The separate effects of alpha-hederin and thymoquinone, the two principal bioactive constituents of Nigella sativa, on four human cancer cell lines [A549 (lung carcinoma), HEp-2 (larynx epidermoid carcinoma), HT-29 (colon adenocarcinoma) and MIA PaCa-2 (pancreas carcinoma)] were investigated. Alpha-hederin was also examined as a pro-drug. Each assessment quantified both cytotoxic and apoptotic/necrotic effects. Alpha-hederin and thymoquinone separately induced a dose- and time-dependent effect on the cell lines tested. HEp-2 cells were the most sensitive, exhibiting apoptosis with a higher incidence following thymoquinone treatment. Pre-treatment of cells with alpha-hederin, followed by thymoquinone or cisplatin, did not enhance the cytotoxicity or apoptosis induced by either drug. So, the membrane-perforating properties associated with saponins, here represented by alpha-hederin, enhance neither cytotoxicity nor apoptosis of these cancer cells.


Assuntos
Benzoquinonas/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias/tratamento farmacológico , Ácido Oleanólico/análogos & derivados , Saponinas/farmacologia , Adenocarcinoma/tratamento farmacológico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29 , Humanos , Concentração Inibidora 50 , Neoplasias Laríngeas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Necrose , Nigella sativa/química , Ácido Oleanólico/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Pró-Fármacos/farmacologia
10.
Clin Radiol ; 60(5): 599-607, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15851049

RESUMO

AIM: To report two new, useful computed tomography (CT) signs of the hypovolaemic shock complex (HSC) in adults admitted after blunt abdominal trauma: the halo sign (ring of fluid around a collapsed intra-hepatic inferior vena cava (IVC)), and peripancreatic retroperitoneal fluid. MATERIALS AND METHODS: CT images of 498 consecutive patients admitted after blunt abdominal trauma were reviewed, of which 27 had CT signs of the HSC. The CT images of these 27 patients were analysed. A control group of 101 patients examined using CT for suspected blunt abdominal trauma who did not have the HSC were chosen for comparison. RESULTS: The most common features involved the vascular compartment: diminished IVC diameter n = 27 a positive halo sign n = 21 diminished anteroposterior diameter of the aorta n = 13 and abnormal vascular enhancement n = 10. Peripancreatic retroperitoneal fluid in the absence of pancreatic injury, pancreatitis or pancreatic disease was observed in eight patients. Hollow visceral abnormalities included: diffuse increased mucosal enhancement of both the small and large bowel n = 19 diffuse thickening of the small bowel wall n =11 and small bowel dilatation n = 7. Solid visceral abnormalities included both decreased and or increased enhancement. Several concomitant intra- and extra-abdominal injuries were also identified. CONCLUSION: In the setting of blunt abdominal trauma, early abdominal CT can show diffuse abnormalities due to the HSC, which occasionally may alert clinicians of unsuspected shock. Recognition of these signs as distinguished from injured viscera is important in order to avoid unnecessary laparotomy. Two new signs are described: the halo sign and peripancreatic retroperitoneal fluid.


Assuntos
Traumatismos Abdominais/diagnóstico por imagem , Pâncreas/diagnóstico por imagem , Choque/diagnóstico por imagem , Ferimentos não Penetrantes/diagnóstico por imagem , Traumatismos Abdominais/complicações , Acidentes de Trânsito , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Exsudatos e Transudatos/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição por Sexo , Choque/etiologia , Tomografia Computadorizada por Raios X , Ferimentos não Penetrantes/complicações
11.
Anticancer Res ; 24(4): 2281-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15330173

RESUMO

We investigated the effects of capillin, a constituent of Artemisia monosperma, on four human tumour cell lines: colon carcinoma H729, pancreatic carcinoma MIA PaCa-2, epidermoid carcinoma of the larynx HEp-2 and lung carcinoma A549. Cells were treated with capillin to examine both the anti-proliferative and pro-apoptotic effects, as well as the molecular mechanism underlying these effects. Changes in cell proliferation, membrane permeability, macromolecular synthesis, glutathione (GSH), cell cycle and programmed cell death were evaluated. Capillin (1microM-10microM) inhibited cell proliferation and decreased macromolecular synthesis simultaneously, in a dose- and time-dependent manner. Co-incubation with L-buthionine sulfoximine (L-BSO) augmented the efficacy of capillin. Capillin modulated GSH levels, accumulated cells in the S+G2/M-phase of the cell cycle and induced cell death and DNA fragmentation, as indicated by flow cytometry, fluorescence microscopy and DNA fragmentation assay. These findings suggest that capillin has cytotoxic activity and can induce apoptosis in human tumour cell lines.


Assuntos
Alcinos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Butionina Sulfoximina/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , DNA de Neoplasias/antagonistas & inibidores , DNA de Neoplasias/biossíntese , Di-Inos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glutationa/metabolismo , Humanos , Neoplasias Laríngeas/tratamento farmacológico , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/biossíntese , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Extratos Vegetais/farmacologia , RNA Neoplásico/antagonistas & inibidores , RNA Neoplásico/biossíntese
12.
Br J Radiol ; 76(908): 566-9, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12893701

RESUMO

We report a case of bilateral adrenal vein thrombosis in an adult female who had a history of breast cancer. The patient does not have clinical, serological or imaging evidence of metastatic disease 14 months from the initial diagnosis. Adrenal vein thrombosis is a rare entity. There have been no previous reports specifically stating an association between adrenal vein thrombosis and hypercoaguability, but there are many cases in the literature documenting venous thrombosis elsewhere within the body in patients with hypercoaguable states. Laboratory testing performed to exclude a hypercoaguable state, revealed heterozygosity for the Factor V Leiden mutation/activated protein C resistance and elevated factor VIII levels [3660 IU l(-1) (<1500)]. This is the first reported case of bilateral metachronous adrenal vein thrombosis in which MRI established the diagnosis.


Assuntos
Glândulas Suprarrenais/irrigação sanguínea , Imageamento por Ressonância Magnética , Trombose Venosa/diagnóstico , Idoso , Neoplasias da Mama/complicações , Carcinoma Ductal de Mama/complicações , Meios de Contraste , Feminino , Febre/etiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Dor/etiologia , Recidiva , Tomografia Computadorizada por Raios X
13.
Phytomedicine ; 10(1): 53-8, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12622464

RESUMO

Ethanolic extracts of 20 plant species, selected from the ethnobotanical literature, were analysed for their pharmacological potential as antineoplastic agents against the HEp-2 cell line. Psoralea corylifolia and E. grandidens were the most efficacious species eliciting IC50 values of 22 microg/ml and 57 microg/ml respectively. Psoralea corylifolia, additionally tested against lung carcinoma (A549) cells gave an IC50 value of 68 microg/ml. Such data would justify a search for active compounds from this species.


Assuntos
Antineoplásicos/farmacologia , Euphorbia , Fitoterapia , Extratos Vegetais/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Frutas , Humanos , Concentração Inibidora 50 , Neoplasias Laríngeas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Raízes de Plantas , Células Tumorais Cultivadas/efeitos dos fármacos
14.
J Nematol ; 35(4): 437-42, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19262777

RESUMO

The activity of an ethanolic rhizome extract of Artemisia vulgaris against hatching, mortality, host plant infectivity, and galling of the root-knot nematode Meloidogyne megadora was investigated. The extract inhibited egg hatch (50% inhibition by 2.35mg/ml) and caused second-stage juvenile mortality (50% lethality at 12 hours' exposure to 55.67 mg/ml), both in a dose-dependent manner. Nematode infectivity on Phaseolus vulgaris 'Bencanta Trepar', a susceptible host, decreased in a dose-responsive manner (50% inhibition at 6.28 hours exposure to extract). When applied directly to the soil, the extract reduced root galling on a susceptible host in a dose-dependent manner (50% inhibition by 32.36 mg/ml). After dilution in distilled water, the extract did not lose activity when stored in the dark at 25 degrees C for 15 days.

15.
J Helminthol ; 76(2): 143-55, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12015827

RESUMO

The ultrastructure of the dorsal oesophageal gland ampulla and its relationship with the oesophagus, oesophageal ultrastructure, and control mechanisms in oesophageal activity were studied. Terminal ducts of the sub-ventral glands open through the oesophageal crown at the base of the buccal cavity. The terminal duct of the dorsal oesophageal gland running through the dorsal gutter opens to the exterior at the rim 'groove' of the buccal capsule. The posterior oesophageal region is clavate and the cuticle of the lumen folds to form outlet valves, 'valvulae'. An inconspicuous oesophago-intestinal valve (three lobes) connects oesophagus and intestine and is visualized in the open and shut position. In the female reproductive tract, with the exception of the uterus, the cells lie on a thick, irregular (convoluted) basal lamina. The apical plasma membrane of the uterus, and seminal receptacle, extend into the lumen by microvilli-like projections with which spermatozoa make intimate contact. The lumen of the uterus is filled with oocytes, fertilized and unfertilized. Testicular cells have two parts linked by a rachis. Spermatocytes are elongated with a large nucleus, distinct nuclear membrane, and many granules. The apical membrane of the rachis forms long microvilli-like projections with balloon-like tips. The amoeboid spermatozoa contain membrane specializations, a nucleus devoid of a membrane, and are enclosed by a pseudopodial-like extension.


Assuntos
Esôfago/ultraestrutura , Genitália/ultraestrutura , Strongylus/ultraestrutura , Animais , Feminino , Genitália Feminina/ultraestrutura , Genitália Masculina/ultraestrutura , Masculino , Microscopia Eletrônica
19.
J Helminthol ; 73(2): 147-55, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10431375

RESUMO

Light, scanning, and transmission electron microscopy were employed to provide further data on the putative origins of the immunogenic secretory-excretory product (ESP) of Strongylus vulgaris (Looss 1900). The sharply delineated but superficial attachment to the equine caecum by the mouth leaves behind an oval area devoid of epithelial cells. Attachment does not extend deeply enough to reach the muscularis mucosa layer of the equine intestine. The progressive digestion of the ingested plug of tissue (epithelial cells, blood cells and mucous) was visualized. The coelomocytes, floating cells and membranous structures located in the pseudocoelom and intimately associated with the digestive, excretory and reproductive systems, and with the somatic muscles are described. The secretory-excretory system comprises two, ventrally-located, secretory-excretory glands connected to tubular elements. These glands synthesize granules of various sizes and densities that are delineated.


Assuntos
Doenças dos Cavalos/parasitologia , Infecções por Strongylida/veterinária , Strongylus/ultraestrutura , Animais , Ceco/parasitologia , Cavalos , Interações Hospedeiro-Parasita , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Infecções por Strongylida/parasitologia , Strongylus/fisiologia
20.
J Nat Toxins ; 8(2): 155-66, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10410327

RESUMO

Acetylcholine receptor (AChR) binding activity was detected in Duvernoy's secretions from B. blandingi and B. dendrophila as they competitively inhibited formation of 3[H]bungarotoxin-acetylcholine receptor complexes (3[H]Bgt-AChR) in a concentration-dependent manner. Secretions contained two types of toxin: low affinity and high affinity. Reversed-phase HPLC of B. blandingi and B. dendrophila secretions afforded 20 and 14 peaks, respectively. AChR binding components, as revealed by SDS-PAGE, had apparent molecular weights of 10 and 11 kDa (B. blandingi) or 11 and 12 kDa (B. dendrophila). Periodic acid-Schiff staining indicated these were not glycoproteins. Alkylation with 4-vinylpyridine significantly decreased their ability to inhibit 3[H]Bgt-AChR binding, indicating disulphide bridges were necessary for receptor-binding activity. Attempts to sequence the B. blandingi peptides were negative as these components seemed to be N-terminally blocked.


Assuntos
Glândulas Exócrinas/metabolismo , Receptores Colinérgicos/metabolismo , Serpentes/fisiologia , Toxinas Biológicas/isolamento & purificação , Animais , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Ligação Proteica , Relação Estrutura-Atividade
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