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1.
Nanoscale Adv ; 1(6): 2216-2228, 2019 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-36131956

RESUMEN

The use of nanoparticles (NPs) in the healthcare market is growing exponentially, due to their unique physicochemical properties. Titanium dioxide nanoparticles (TiO2 NPs) are used in the formulation of sunscreens, due to their photoprotective capacity, but interactions of these particles with skin cells on the nanoscale are still unexplored. In the present study we aimed to determine whether the initial nano-biological interactions, namely the formation of a nano-bio-complex (other than the protein corona), can predict rutile internalization and intracellular trafficking in primary human fibroblasts and keratinocytes. Results showed no significant effect of NPs on fibroblast and keratinocyte viability, but cell proliferation was possibly compromised due to nano-bio-interactions. The bio-complex formation is dependent upon the chemistry of the biological media and NPs' physicochemical properties, facilitating NP internalization and triggering autophagy in both cell types. For the first time, we observed that the intracellular traffic of NPs is different when comparing the two skin cell models, and we detected NPs within multivesicular bodies (MVBs) of keratinocytes. These structures grant selected input of molecules involved in the biogenesis of exosomes, responsible for cell communication and, potentially, structural equilibrium in human tissues. Nanoparticle-mediated alterations of exosome quality, quantity and function can be another major source of nanotoxicity.

2.
Eur J Obstet Gynecol Reprod Biol ; 232: 60-64, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30468985

RESUMEN

OBJECTIVES: Episiotomy is a marker of Obstetric Anal Sphincter Injury (OASIS) condition, therefore, unmeasured factors could have biased the strength of the association between episiotomy and reduced OASIS during Operative Vaginal Delivery (OVD). The aim of this study was to compare the OASIS rate during OVD according to episiotomy practice. STUDY DESIGN: Retrospective cohort study of all nulliparous pregnant women attempting an OVD between 2014-2017. To avoid unmeasured bias, all maternal and delivery data were prospectively captured after the birth. The strong relationship between parity and episiotomy practice (indication bias) lead to analyze only nulliparous women. Association between mediolateral episiotomy and OASIS following OVD was performing by using multivariate logistic regression analysis including significant variable in univariate analysis and relevant factors known to be associated both with OASIS and/or OVD. RESULTS: Over the study period, 1709 (17.1%) women had an OVD, among them 40 (2.3%) had OASIS. In the 1342 (78.5%) nulliparous women, OASIS rate were 2% and 5.1% with and without episiotomy (p < 0.01). In multivariate analysis a lower incidence of OASIS with the use of episiotomy (OR 0.267 IC 0.132-0.541) were observed. The persistent occiput posterior position was associated with an increase risk of OASIS (OR 6.742 IC 2.376-19.124). Spatula/forceps, as compared to vacuum operative vaginal delivery increased the risk OASIS (OR 2.847 IC 1.311-7.168). Area under the curve of the model was 0.745. CONCLUSION: Episiotomy is a modifiable risk factors which can contribute to reduce the risk of OASIS in nulliparous women with operative vaginal delivery. This intervention should be included in a global management of the second stage of labor.


Asunto(s)
Canal Anal/lesiones , Parto Obstétrico/efectos adversos , Episiotomía , Complicaciones del Trabajo de Parto/prevención & control , Adulto , Femenino , Humanos , Incidencia , Complicaciones del Trabajo de Parto/epidemiología , Paridad , Embarazo , Estudios Retrospectivos , Factores de Riesgo
3.
J Obstet Gynaecol Can ; 40(8): 1031-1037, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29887362

RESUMEN

OBJECTIVE: To assess the effect of successful external cephalic version (ECV) on the risk of caesarean section (CS) during attempted vaginal delivery after induction of labour. METHODS: A unicentric matched retrospective observational case-control cohort study with exposed and unexposed groups. All pregnant women who had an induction of labour after a successful external cephalic version (sECV) between 1998 and 2016 were included. A total of 88 cases were compared with 176 controls (spontaneous cephalic presentation), matching for the year of delivery, parity, gestational age, indication and mode of induction of labour. The main outcome measure was the risk of caesarean. A univariate analysis and a multivariate logistic regression analysis were performed. RESULTS: The caesarean section rate was significantly higher after sECV (22% versus 13.1%; p = 0.039) especially for postdate pregnancy (55% versus 8.2%; p <0.05). For the univariate analysis, age (31 years and 4 months versus 24 years and 6 months; p <0.01) and maximal speed of oxytocin infusion (72 ml/h versus 68 ml/h; p = 0.04) were higher in the case group. The multivariate analysis showed that the risk of caesarean section was significantly increased after an sECV (aOR 1.946; 95% CI 1.017-3.772) and after the use of prostaglandins for ripening (aOR 1.951; 95% CI 1.097-3.468), and decreased for multipara (aOR 0.208; 95% CI 0.114-0.377). CONCLUSION: Women who have a successful ECV are at increased risk of caesarean section after subsequent induction of labour.


Asunto(s)
Cesárea/estadística & datos numéricos , Versión Fetal , Adulto , Estudios de Casos y Controles , Femenino , Francia/epidemiología , Edad Gestacional , Humanos , Trabajo de Parto Inducido , Paridad , Embarazo , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
4.
J Gynecol Obstet Hum Reprod ; 46(4): 349-354, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28643663

RESUMEN

OBJECTIVE: Polyhydramnios is associated with an increased risk of cesarean section. The aetiology of polyhydramnios and the characteristics of the labour may be confounding factors. The objective was to study the characteristics and mode of delivery in case of pregnancy complicated with idiopathic polyhydramnios. METHODS: This retrospective matched and controlled study included all pregnant women with idiopathic polyhydramnios (amniotic index>25cm or single deepest pocket>8cm) diagnosed at the 2nd or 3rd trimester and persistent at term delivery (>37weeks of pregnancy) in our institution. We excluded pregnancies in which the polyhydramnios could be explained by infection, gestational diabetes, congenital malformation, abnormal karyotype, placental anomalies, alloimmunization as well as pregnancies in which an amniocentesis for the purpose of diagnosis had not been performed. Data were gathered from a tertiary care university hospital register from 1998-2015. Cases of polyhydramnios were matched with the following two women who presented for labour management with spontaneous cephalic presentation, matching for delivery date, maternal age, parity, body mass index. The main outcome measure was the risk of cesarean section. Univariate and multivariate adjusted analysis were performed. RESULTS: We identified 108 women with idiopathic polyhydramnios and compared them with 216 matched women. Among them, 94 and 188 attempted a trial of labour. Maternal age, mean term delivery and birthweight were 31 years, 39+5weeks gestation and 3550 g. We did not observe differences in maternal characteristics, epidural analgesia and rate of abnormal fetal heart tracing. Induced labour and non-vertex presentations (forehead, bregma, face) were more frequent in the polyhydramnios group (respectively 57.9% versus 27.8%, P<0.05 and 7.8% versus 1%, P<0.05). Cesarean section rate was higher in the case of polyhydramnios in the overall population (45.4% versus 8%, P<0.05) and remained higher after exclusion of cases of induced labour and non-vertex presentation (38.4% versus 3.8%, P<0.05). Amniotomy was more frequent in pregnancies with polyhydramnios (55.8% versus 39.1%, P<0.05). After adjustment for matching and confounding variables, polyhydramnios was found to be a risk factor for cesarean section (OR 21.02; CI 95% 8.004-55.215, P<0.01). CONCLUSION: Idiopathic polyhydramnios increased the risk of prolonged first stage of labour, non-vertex presentation and cesarean section.


Asunto(s)
Complicaciones del Trabajo de Parto/diagnóstico , Complicaciones del Trabajo de Parto/epidemiología , Polihidramnios/diagnóstico , Polihidramnios/epidemiología , Resultado del Embarazo/epidemiología , Nacimiento a Término , Adulto , Estudios de Casos y Controles , Parto Obstétrico/estadística & datos numéricos , Femenino , Humanos , Complicaciones del Trabajo de Parto/terapia , Polihidramnios/terapia , Embarazo , Tercer Trimestre del Embarazo , Pronóstico , Estudios Retrospectivos , Adulto Joven
5.
Cell Microbiol ; 17(8): 1217-29, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25703821

RESUMEN

The parasite Trichomonas vaginalis is the causative agent of trichomoniasis, a prevalent sexually transmitted infection. Here, we report the cellular analysis of T.vaginalis tetraspanin family (TvTSPs). This family of membrane proteins has been implicated in cell adhesion, migration and proliferation in vertebrates. We found that the expression of several members of the family is up-regulated upon contact with vaginal ectocervical cells. We demonstrate that most TvTSPs are localized on the surface and intracellular vesicles and that the C-terminal intracellular tails of surface TvTSPs are necessary for proper localization. Analyses of full-length TvTSP8 and a mutant that lacks the C-terminal tail indicates that surface-localized TvTSP8 is involved in parasite aggregation, suggesting a role for this protein in parasite : parasite interaction.


Asunto(s)
Tetraspaninas/análisis , Trichomonas vaginalis/química , Agregación Celular , Vesículas Citoplasmáticas/química , Análisis Mutacional de ADN , Células Epiteliales/parasitología , Perfilación de la Expresión Génica , Proteínas de la Membrana/análisis , Transporte de Proteínas , Trichomonas vaginalis/genética
6.
Braz. j. med. biol. res ; 43(10): 950-956, Oct. 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-561232

RESUMEN

We examined the degeneration of post-mitotic ganglion cells in ex-vivo neonatal retinal explants following axon damage. Ultrastructural features of both apoptosis and autophagy were detected. Degenerating cells reacted with antibodies specific for activated caspase-3 or -9, consistent with the presence of caspase activity. Furthermore, peptidic inhibitors of caspase-9, -6 or -3 prevented cell death (100 µM Ac-LEDH-CHO, 50 µM Ac-VEID-CHO and 10 µM Z-DEVD-fmk, respectively). Interestingly, inhibition of autophagy by 7-10 mM 3-methyl-adenine increased the rate of cell death. Immunohistochemistry data, caspase activation and caspase inhibition data suggest that axotomy of neonatal retinal ganglion cells triggers the intrinsic apoptotic pathway, which, in turn, is counteracted by a pro-survival autophagic response, demonstrated by electron microscopy profiles and pharmacological autophagy inhibitor.


Asunto(s)
Animales , Ratas , Apoptosis/fisiología , Autofagia/fisiología , Caspasa 9/metabolismo , /metabolismo , Células Ganglionares de la Retina/enzimología , Axotomía , Autofagia/efectos de los fármacos , Inmunohistoquímica , Microscopía Electrónica de Transmisión , Células Ganglionares de la Retina/ultraestructura
7.
Braz J Med Biol Res ; 43(10): 950-6, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20802972

RESUMEN

We examined the degeneration of post-mitotic ganglion cells in ex-vivo neonatal retinal explants following axon damage. Ultrastructural features of both apoptosis and autophagy were detected. Degenerating cells reacted with antibodies specific for activated caspase-3 or -9, consistent with the presence of caspase activity. Furthermore, peptidic inhibitors of caspase-9, -6 or -3 prevented cell death (100 µM Ac-LEDH-CHO, 50 µM Ac-VEID-CHO and 10 µM Z-DEVD-fmk, respectively). Interestingly, inhibition of autophagy by 7-10 mM 3-methyl-adenine increased the rate of cell death. Immunohistochemistry data, caspase activation and caspase inhibition data suggest that axotomy of neonatal retinal ganglion cells triggers the intrinsic apoptotic pathway, which, in turn, is counteracted by a pro-survival autophagic response, demonstrated by electron microscopy profiles and pharmacological autophagy inhibitor.


Asunto(s)
Apoptosis/fisiología , Autofagia/fisiología , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Células Ganglionares de la Retina/enzimología , Animales , Autofagia/efectos de los fármacos , Axotomía , Inmunohistoquímica , Microscopía Electrónica de Transmisión , Ratas , Células Ganglionares de la Retina/ultraestructura
8.
Parasitol Int ; 59(3): 387-93, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20483382

RESUMEN

Trichomonas vaginalis is an important human parasite of the urogenital tract. Jasmonates are a group of small lipids that are produced in plants and function as stress hormones. Naturally occurring methyl jasmonate (MJ) has been used to treat several types of cancer cells and it is cytotoxic to protistan parasites. It has been suggested that mitochondria are the target organelles of jasmonates. Here, we tested this drug against T. vaginalis. Although metronidazole has been the drug of choice for trichomoniasis, side effects from this treatment are common, and nausea and dizziness have been reported in up to 12% of patients. In addition, there has been increased recognition of resistance to metronidazole. We demonstrate here using flow cytometry, JC-1 and scanning and transmission electron microscopy that MJ induced the cell death of T. vaginalis parasites. Our results are discussed with previous findings published by others.


Asunto(s)
Acetatos/farmacología , Antitricomonas/farmacología , Muerte Celular , Ciclopentanos/farmacología , Oxilipinas/farmacología , Trichomonas vaginalis/efectos de los fármacos , Animales , Muerte Celular/efectos de los fármacos , Línea Celular , Perros , Citometría de Flujo , Hidrógeno/metabolismo , Riñón/citología , Riñón/parasitología , Potenciales de la Membrana/efectos de los fármacos , Microscopía Electrónica , Orgánulos , Trichomonas vaginalis/fisiología , Trichomonas vaginalis/ultraestructura
10.
Parasitology ; 137(1): 65-76, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19723359

RESUMEN

This study reports that the cytopathic effect of Trichomonas vaginalis, an important human parasite of the urogenital tract, occurs due to mechanical stress and subsequent phagocytosis of the necrotic cells. The investigation was done using a primary culture of bovine oviduct epithelial cells (BOECs), grown either in monolayers or as floating cells. Trophozoites displaying different virulence levels were co-incubated with BOECs for times varying between 1 min and 48 h. Analyses were performed using videomicroscopy, scanning and transmission electron microscopy, colourimetric assays and cytochemistry. Injury was observed as early as 1 h after incubation, while after 12 h the host cells were severely damaged when a fresh trichomonad isolate was used. Trichomonads attack the host cells by clustering around them. Mechanical stress on the microvilli of the host cells was observed and appeared to induce plasma membrane damage and cell death. After membrane injury and lysis, fragments of the necrotic cells were ingested by trichomonads. Phagocytosis occurred by trichomonads avidly eating large portions of epithelial cells containing the nucleus and other organelles, but living or intact cells were not ingested. Necrotic fragments were rapidly digested in lysosomes, as shown by acid phosphatase and ruthenium red assays where only the BOECs were labelled. The lytic capacity of the trichomonads was more pronounced in host cell suspensions.


Asunto(s)
Células Epiteliales/parasitología , Interacciones Huésped-Parásitos , Oviductos/parasitología , Fagocitosis , Trichomonas vaginalis/patogenicidad , Animales , Bovinos , Células Cultivadas , Femenino , Humanos , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Oviductos/citología , Trichomonas vaginalis/crecimiento & desarrollo , Trichomonas vaginalis/fisiología , Trofozoítos , Virulencia
11.
Vet Parasitol ; 165(3-4): 216-30, 2009 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-19665307

RESUMEN

Tritrichomonas foetus is an extracellular parasite of the reproductive tract in cattle. To investigate the cytopathic effects of T. foetus in deeper parts of the reproductive tract, a bovine primary oviduct epithelial cell system (BOECs) was developed. Reproductive tracts were obtained from cows and the effect of co-incubating T. foetus with BOECs was analyzed by scanning electron, transmission electron and fluorescence microscopy. Viability tests were performed using colorimetric methods, TUNEL (Terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling), fluorescein diacetate, propidium iodide, JC-1 and annexin-V. The results demonstrate that: (1) the in vitro oviduct epithelium is useful for interaction experiments with T. foetus; (2) T. foetus adheres to the BOECs as single separate cells, and later on the cells aggregate as large clusters; (3) the posterior region of the cell initiates the process of adhesion and forms filopodia and digitopodia; (4) T. foetus severely damages BOECs leaving imprints in the epithelial cells, wide intercellular spaces, and large lesions in the epithelium; and (5) T. foetus provokes bovine oviduct cell death by apoptosis and secondary necrosis. Our observations indicate the possibility that T. foetus can move through the reproductive tract to the oviduct and that infertility in cows can be mediated by an attack on the oviduct cells by T. foetus.


Asunto(s)
Enfermedades de los Bovinos/parasitología , Oviductos/parasitología , Infecciones Protozoarias en Animales/parasitología , Tritrichomonas foetus/fisiología , Animales , Apoptosis , Bovinos , Enfermedades de los Bovinos/patología , Células Cultivadas , Células Epiteliales/citología , Células Epiteliales/parasitología , Células Epiteliales/ultraestructura , Femenino , Etiquetado Corte-Fin in Situ , Mitocondrias/fisiología , Oviductos/citología , Oviductos/patología , Infecciones Protozoarias en Animales/patología , Factores de Tiempo
12.
Eur J Clin Microbiol Infect Dis ; 27(4): 259-67, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18040730

RESUMEN

The parasite Trichomonas vaginalis causes one of the most common non-viral sexually transmitted infections in humans. Mycoplasmas are frequently found with trichomonads but the consequences of this association are not yet known. In the present study, the effects of T. vaginalis harboring M. hominis on human vaginal epithelial cells and on MDCK cells are described. The results were analyzed by light, scanning and transmission electron microscopy, as well as using cell viability assays. There was an increase in the cytopathic effects on the epithelial cells infected with T. vaginalis associated with M. hominis compared to T. vaginalis alone. The epithelial cells exhibited an increase in the intercellular spaces, a lesser viability, and increased destruction provoked by the infected T. vaginalis. In addition, the trichomonads presented a higher amoeboid transformation rate and an intense phagocytic activity, characteristics of higher virulence behavior.


Asunto(s)
Células Epiteliales/parasitología , Mycoplasma hominis/aislamiento & purificación , Trichomonas vaginalis/microbiología , Trichomonas vaginalis/patogenicidad , Animales , Antibacterianos/farmacología , Células Cultivadas , Células Epiteliales/ultraestructura , Femenino , Humanos , Pruebas de Sensibilidad Microbiana , Vagina/citología
13.
Gynecol Obstet Fertil ; 35(4): 327-9, 2007 Apr.
Artículo en Francés | MEDLINE | ID: mdl-17336127

RESUMEN

Vasa previa is a rare condition (1/2000 to 1/5000) in which the rupture of membranes may result in fetal haemorrhage (Benckiser's haemorrhage). We report one unusual case of delayed Benckiser's haemorrhage 12 hours after rupture of membranes. We point out the risk situations in which prenatal diagnosis should particularly be sought: low-lying placenta at routine second trimester ultrasound screening, bilobate or succenturiate placenta, velamentous insertion of the umbilical cord, in vitro fertilization. A universal screening, as proposed by certain authors, is also discussed.


Asunto(s)
Ultrasonografía Prenatal , Arterias Umbilicales/anomalías , Venas Umbilicales/anomalías , Adulto , Diagnóstico Diferencial , Femenino , Rotura Prematura de Membranas Fetales , Hemorragia/diagnóstico , Hemorragia/prevención & control , Humanos , Recién Nacido , Masculino , Placenta/irrigación sanguínea , Placenta/patología , Embarazo , Resultado del Embarazo , Rotura Espontánea , Arterias Umbilicales/diagnóstico por imagen , Venas Umbilicales/diagnóstico por imagen
14.
Diabetes Metab ; 32(2): 140-6, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16735962

RESUMEN

AIM: The benefit of treating gestational diabetes mellitus (GDM) has recently been shown. The aim of this study was to compare offspring and maternal health benefits from selective or universal screening for GDM. METHODS: The incidence of outcomes was compared in three series of pregnant women: 1) the 159 consecutive women with GDM out of the 1909 women who delivered between October 2000 and September 2001: during this period screening for GDM was based on risk factors (risk factor-GDM); 2) the 265 consecutive women with GDM out of the 2111 women who delivered during the year 2002: during this period screening for GDM was universal (universal-GDM); 3) 1255 women with no GDM during year 2002 (controls). RESULTS: After adjustment for age, pregravid body mass index, parity, and ethnicity, the risk of large for gestational age (Odds ratio 2.19[95% confidence interval 1.36-3.54], P < 10(-3)), delivery before 37 weeks of gestation (OR 2.44 [95CI 1.32-4.51], P = 0.004), jaundice (OR 3.31[95CI 1.58-6.93], P = 0.002), hospitalization in the department of pediatrics (OR 2.35 [95CI 1.53-3.61], P < 10(-3)) was higher in the GDM-risk factor group than in the control group, whereas it was similar in the universal-GDM group and the control group. Compared with the control group, the risk of anticipated delivery and hospital stay > 4 days after delivery was increased in the GDM-risk factor group (OR 2.69[1.88-3.84], P < 10(-3); and OR 2.6 [1.82-3.71], P < 10(-3) respectively) and the universal-GDM group (OR 1.54 [1.15-2.07] P = 0.004; and OR 1.49 [1.13-1.97], P = 0.005 respectively). CONCLUSION: This observational study suggests that universal rather than selective screening for GDM may improve outcomes. Universal screening might reduce delay of diagnosis and care.


Asunto(s)
Diabetes Gestacional/diagnóstico , Diabetes Gestacional/epidemiología , Desarrollo Fetal/fisiología , Tamizaje Masivo/métodos , Resultado del Embarazo , Adulto , Índice de Masa Corporal , Femenino , Geografía , Humanos , Recién Nacido , Tamizaje Masivo/normas , Monitoreo Fisiológico/métodos , Embarazo , Factores de Riesgo , Fumar
15.
Gynecol Obstet Fertil ; 34(2): 107-14, 2006 Feb.
Artículo en Francés | MEDLINE | ID: mdl-16442325

RESUMEN

OBJECTIVE: Screening strategies for gestational diabetes mellitus are controversial. Thus, we sought to determine the benefits of universal screening. PATIENTS AND METHODS: Prospective study with 2121 women involved but 1610 really screened (75.9%). According to WHO's recommendations, the strategy implemented was one-step, universal screening with a 75g oral glucose tolerance test. Screening was performed between 24 and 28 weeks of gestation or earlier if risk factors were identified. Results were compared to previous year (2001) then only a selective screening was done. RESULTS: Application of universal screening increased the prevalence of gestational diabetes mellitus (8.39% to 15.65%). Out of the 252 patients with gestational diabetes, 66 did not display any identified risk factor (26.19%). Some new risk factors have been identified: age>30, Asian, Indian or Pakistan ethnies. If these new risk factors were applied, this super selective screening would have a sensibility of 96%. DISCUSSION AND CONCLUSION: Universal screening seems to be the most appropriate routine screening strategy because it is difficult to know exactly the specific risk factors of a population to do a super selective screening.


Asunto(s)
Diabetes Gestacional/diagnóstico , Diabetes Gestacional/epidemiología , Prueba de Tolerancia a la Glucosa , Tamizaje Masivo , Adulto , Factores de Edad , Índice de Masa Corporal , Análisis Costo-Beneficio , Femenino , Humanos , Paridad , Embarazo , Segundo Trimestre del Embarazo , Estudios Prospectivos , Factores de Riesgo
16.
Infect Immun ; 73(5): 2602-10, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15845462

RESUMEN

Trichomonas vaginalis secretes putrescine that is readily detected in vaginal secretions. We wanted to examine the effect of decreased putrescine synthesis by inhibition of ornithine decarboxylase (ODC) on T. vaginalis. One reason is because inhibition of Tritrichomonas foetus ODC results in growth arrest, destruction of hydrogenosomes, and decreased amounts of hydrogenosomal enzymes. Treatment of T. vaginalis T016 with >/=20 mM 1,4-diamino-2-butanone (DAB) to inhibit ODC resulted in growth arrest, which was reversed by addition of exogenous putrescine. No similar reversal of growth arrest was achieved with the polyamines spermine or spermidine or with iron. Electron microscopic examination of control versus DAB-treated trichomonads did not reveal any adverse effects on the number and integrity of hydrogenosomes. Further, the adhesins AP65, AP51, and AP33 mediating binding to immortalized vaginal epithelial cells (VECs) share identity to enzymes of the hydrogenosome organelle, and there was no difference in amounts of adhesins between control versus DAB-treated T. vaginalis parasites. Likewise, similar patterns and extent of fluorescence were evident for the prominent AP65 adhesin. Surprisingly, DAB treatment increased by 4- to 20-fold above untreated trichomonads handled identically the level of adherence mediated by adhesins. Interestingly, the enhanced attachment to VECs was reversed by exogenous putrescine added to DAB-treated trichomonads. Equally noteworthy was that DAB-treated T. vaginalis with enhanced adherence did not possess the previously reported ability to kill host cells in a contact-dependent fashion mediated by cysteine proteinases, and total cysteine proteinase activity patterns were identical between control and DAB-treated trichomonads. Overall, these data suggest that polyamine metabolism and secreted putrescine are linked to host cell adherence and cytotoxicity.


Asunto(s)
Poliaminas/metabolismo , Putrescina/análogos & derivados , Trichomonas vaginalis/fisiología , Trichomonas vaginalis/patogenicidad , Vagina/citología , Vagina/parasitología , Animales , Adhesión Celular , Línea Celular , Células Epiteliales/parasitología , Células Epiteliales/patología , Femenino , Humanos , Putrescina/biosíntesis , Putrescina/farmacología , Trichomonas vaginalis/efectos de los fármacos , Trichomonas vaginalis/metabolismo , Vagina/patología , Virulencia
17.
Tissue Cell ; 36(2): 95-105, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15041411

RESUMEN

Melanin is a dark pigment protecting the skin against UV radiation in some organisms. Studies on invasion and metastasis using retinoic acid as inhibitor agent are well known, but its role in melanin production (melanogenesis), especially at ultrastructural level and using morphometry were not well studied. In the present study, we analyzed the effects of retinoic acid on the melanosomes in B16F10 melanoma cells. These organelles were identified and quantified using routine electron microscopy and the specific HMB45 antibody. Other approaches such as immunofluorescence, and flow cytometry were also used. Our results indicated that retinoic acid increased the melanogenesis process in B16F10 melanoma cells. Furthermore, this work also provided evidence that this substance interferes at the subcellular level altering the numerical density of melanosomes, as well as the relative volume of the nucleus and nucleolus. In addition, the cells displayed altered morphology and an increase in the percentage of the relative volume of melanosomes, mainly the stages II-III and IV, leading to melanin formation. Furthermore, a decrease in the cells number after retinoic acid treatment was also observed.


Asunto(s)
Antineoplásicos/farmacología , Melaninas/biosíntesis , Melanosomas/metabolismo , Tretinoina/farmacología , Animales , División Celular/efectos de los fármacos , Línea Celular Tumoral , Núcleo Celular/metabolismo , Núcleo Celular/ultraestructura , Citometría de Imagen , Melanoma/metabolismo , Melanoma/ultraestructura , Melanosomas/ultraestructura , Ratones , Microscopía Confocal , Microscopía Electrónica
18.
Gynecol Obstet Fertil ; 31(10): 841-3, 2003 Oct.
Artículo en Francés | MEDLINE | ID: mdl-14642941

RESUMEN

The ossification of the endometrium is a rare disease. The common feature in most reported cases is previous history of abortion with retention of foetal bones. However, the physiopathology is unknown. Clinical presentation may include secondary infertility as well as chronic inflammation of endometrium. About one recent observation and with help of publications, we will discuss physiopathology, symptomatology and therapeutics of this disease.


Asunto(s)
Aborto Inducido/efectos adversos , Endometrio/patología , Osificación Heterotópica/cirugía , Adulto , Femenino , Humanos , Histeroscopía , Osificación Heterotópica/etiología , Embarazo
19.
Exp Parasitol ; 103(1-2): 44-50, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12810045

RESUMEN

Some isolates of Trichomonas vaginalis, the number one, non-viral sexually transmitted disease agent, are infected with one or several distinct double stranded (ds)-RNA virus. Immune rabbit anti-capsid serum (IRS) reacted with the capsid protein of purified dsRNA virus of a subset of the virus-infected T. vaginalis isolates. A monoclonal antibody (mAb) that recognized the capsid protein reactive with the IRS was generated. Analysis of the virus capsid protein of virus-infected isolates by probing nitrocellulose blots with mAb revealed diversity among immunoreactivity and in the size of the reactive capsid protein. Despite difficulties in visualizing virus within parasites by cross-section electron microscopy, gold-conjugated mAb readily labeled the cytoplasm of virus-positive trichomonads. Finally and importantly, isolates infecting patients attending an STD clinic, 75% of which were virus-positive isolates, had capsid protein of the same size detected by mAb present in all dsRNA viruses.


Asunto(s)
Proteínas de la Cápside/análisis , Virus ARN/aislamiento & purificación , ARN Bicatenario/análisis , Tricomoniasis/parasitología , Trichomonas vaginalis/virología , Animales , Anticuerpos Monoclonales/inmunología , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Electroforesis en Gel de Poliacrilamida , Humanos , Hibridomas , Sueros Inmunes/inmunología , Immunoblotting , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C , Virus ARN/genética , ARN Viral/análisis , Enfermedades de Transmisión Sexual/parasitología
20.
Tissue Cell ; 34(6): 406-15, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12441093

RESUMEN

In the present work, we demonstrate virus-like particles (VLPs) with various morphological variations in Trichomonas vaginalis. The VLPs were distinct based on size, shape and electron density, with VLPs being either electron-dense or electron-lucent. We used electron microscopy thin sections of several T. vaginalis strains virus-infected, and also negative staining of fractions obtained after purification by CsCl buoyant density gradient centrifugation. The particles observed in fractions are identical to those previously described, but by thin sections, we found new forms. The shapes found were icosahedral, spherical and oblong, and the sizes varied from 33 to 120nm in diameter with the most common VLP being spherical and having a size range from 83 to 104nm. The VLPs were found in the cytoplasm closely associated with the Golgi complex, with some VLPs budding from the Golgi, and other VLPs were detected adjacent to the plasma membrane. Unidentified cytoplasmic inclusions were observed in the region close to the VLPs and Golgi. Clusters of the already described icosahedral virus were also observed in the cytoplasm, although less frequently. These results indicate that T. vaginalis organisms may be infected with different dsRNA viruses simultaneously.


Asunto(s)
Trichomonas vaginalis/virología , Virión/ultraestructura , Animales , Proteínas de la Cápside/análisis , Microscopía Electrónica , Microscopía Inmunoelectrónica , ARN Bicatenario/análisis , Trichomonas vaginalis/crecimiento & desarrollo , Trichomonas vaginalis/ultraestructura , Virión/química , Virión/aislamiento & purificación
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