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1.
Anal Bioanal Chem ; 412(16): 3915-3923, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31989195

RESUMO

Sequestration of Plasmodium falciparum-infected erythrocytes (IEs) is responsible for the pathophysiology of placental malaria, leading to serious complications such as intrauterine growth restriction and low birth weight. However, it is an experimental challenge to study the biology of human placenta. Conventional cell culture-based in vitro placental models rely on immunostaining techniques and high-magnification microscopy is limited in providing real-time quantitative analysis. Impedimetric sensing in combination with cell culture may offer a useful tool. In this paper, we report that real-time label-free measurement of cellular electrical impedance using xCELLigence technology can be used to quantify the proliferation, syncytial fusion, and long-term response of BeWo cells to IEs cytoadhesion. Specifically, we optimized key experimental parameters of cell seeding density and concentration of forskolin, a compound used to promote cell syncitiation, based on electrical signals and immunostaining results. Prolonged time of infection with IEs that led to cell-cell junction vanishment in BeWo cells and release of inflammatory cytokines were monitored in real time by continuous change in electrical impedance. The results suggest that the impedimetric technique is sensitive and can offer new opportunities for the study of cellular responses of trophoblast cells to IEs. The developed system can provide potentially a high-throughput screening tool of anti-adhesion or anti-inflammatory drugs for placental malaria infections.


Assuntos
Eritrócitos/patologia , Malária Falciparum/patologia , Complicações Parasitárias na Gravidez/patologia , Trofoblastos/patologia , Linhagem Celular , Feminino , Humanos , Técnicas In Vitro , Malária Falciparum/complicações , Gravidez
2.
Infect Dis Obstet Gynecol ; 2019: 2094560, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30940990

RESUMO

Background: Malaria during pregnancy may threaten the mother's health and cause serious structural damage to the internal architecture of the placenta, which subsequently affects the pregnancy outcome. A better understanding of the impact of malaria parasites on the placenta morphology is crucial for better management of pregnant women and their babies. Aim: To assess by stereology the histomorphology of selected placental structures in placenta malaria compared with normal placentae at term. Method: A total of 10 placentae comprising 5 controls and 5 cases were selected from 50 placentae that were collected at term (38 weeks ± 2 weeks) from the maternal delivery suit of Korle-Bu Teaching Hospital in Accra, Ghana. Blood from the placentae was collected for both rapid diagnostic test and microscopic examinations. Samples collected were examined for Plasmodium parasites, after which they were classified as study group (Plasmodium positive) or control (Plasmodium negative). Stereological quantification using systematic uniform random sampling technique with test point and intersection counting of photomicrographs were employed to estimate the mean volume densities of syncytial knots, syncytial necrosis, foetal capillaries, and intervillous spaces of the placentae on a total of 1,600 photomicrographs. Results: Out of the fifty placental samples from the maternal side tested for Plasmodium, six representing 12% were found to be infected with the parasite by both rapid diagnostic test and microscopy. On stereological assessment, the mean volume density of syncytial knots was significantly higher in the placental malaria group compared with the control placentae at term (P = 0.0080), but foetal capillaries (P = 0.7813), intervillous spaces (P = 0.8078), and syncytial necrosis (P = 0.8249) were not significantly different. Conclusion: This preliminary result indicates that placental malaria may cause significant increase in the syncytial knots but not foetal capillaries, intervillous spaces, or syncytial necrosis. This finding signifies early maturation of the placenta and may be crucial in understanding perinatal outcomes.


Assuntos
Malária/patologia , Doenças Placentárias/parasitologia , Placenta/patologia , Complicações Parasitárias na Gravidez/patologia , Feminino , Humanos , Fotomicrografia , Doenças Placentárias/patologia , Gravidez
3.
Parasite Immunol ; 40(9): e12570, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29971806

RESUMO

Congenital toxoplasmosis is caused by the vertical transmission of infection from mother to foetus through the placenta when a pregnant woman is infected with Toxoplasma gondii (T. gondii). Congenital infection can have serious consequences, such as intrauterine abortion, foetal death and severe neurological, ocular or other organ damage in the foetus. In this review, we focus on recent publications investigating vertical transmission of T. gondii infection, cellular immunopathogenesis and protective immunity in primary toxoplasmosis during pregnancy.


Assuntos
Complicações Parasitárias na Gravidez/parasitologia , Toxoplasma/fisiologia , Toxoplasmose/imunologia , Animais , Feminino , Humanos , Transmissão Vertical de Doenças Infecciosas , Masculino , Placenta/imunologia , Placenta/parasitologia , Gravidez , Complicações Parasitárias na Gravidez/imunologia , Complicações Parasitárias na Gravidez/patologia , Toxoplasma/genética , Toxoplasmose/parasitologia , Toxoplasmose/patologia , Toxoplasmose/transmissão
4.
Vet Res ; 49(1): 42, 2018 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-29739449

RESUMO

Experimental infections in pregnant sheep have been focused on studying the effect of the time of challenge on the outcome of N. caninum infection, whereas the impact of the dose and route of challenge has not been studied in depth. Therefore, clinical outcome, immune responses, parasite detection and burden, and lesion severity in placental tissues and foetal brains were investigated in 90-day-pregnant sheep inoculated intravenously with 105 (G1), 104 (G2), 103 (G3), or 102 (G4) tachyzoites or subcutaneously with 104 (G5) tachyzoites of the virulent Nc-Spain7 isolate and an uninfected group (G6). Comparing challenge doses, G1 was the only group that had 100% abortion. Likewise, IFNγ levels in G1 increased earlier than those in other intravenously infected groups, and IgG levels on day 21 post-infection (pi) were higher in G1 than those in other intravenously infected groups. Concerning vertical transmission, G1 shows a higher parasite burden in the foetal brain than did G2 and G3. Comparing routes of administration, no differences in foetal survival rate or parasite load in the foetal brain were found. Although G2 had higher IFNγ levels than G5 on day 10 pi, no differences were found in humoral immune responses. Because the outcome after intravenous infection with 105 tachyzoites was similar to that observed after intravenous infection with 106 tachyzoites used in a previous work (100% abortion and vertical transmission), we conclude that it may be reasonable to use 105 tachyzoites administered by the intravenous route in further experiments when assessing drugs or vaccine candidates.


Assuntos
Coccidiose/veterinária , Neospora/fisiologia , Complicações Parasitárias na Gravidez/veterinária , Doenças dos Ovinos/imunologia , Doenças dos Ovinos/patologia , Animais , Coccidiose/imunologia , Coccidiose/parasitologia , Coccidiose/patologia , Feminino , Feto/parasitologia , Imunidade Celular , Imunidade Humoral , Carga Parasitária/veterinária , Placenta/parasitologia , Gravidez , Complicações Parasitárias na Gravidez/imunologia , Complicações Parasitárias na Gravidez/parasitologia , Complicações Parasitárias na Gravidez/patologia , Ovinos , Doenças dos Ovinos/parasitologia
5.
J Biochem Mol Toxicol ; 31(7)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28238206

RESUMO

Increased TNF-α levels have been associated with adverse pregnancy outcomes. Lipopolysaccharide (LPS), 1,1,1-trichloro-2,2-bis-(chlorophenyl)ethane (DDT), 1,1-bis-(chlorophenyl)-2,2-dichloroethene (DDE), and 1,1-dichloro-2,2-bis(chlorophenyl)ethane (DDD) induce TNF-α release in peripheral blood mononuclear cells (PBMC). Conversely, progesterone (P4) inhibits TNF-α secretion. Pregnant women in malaria endemic areas may be co-exposure to these compounds. Thus, this study was to investigate the synergistic effect of LPS and these pesticides in PBMC and to assess P4 influence on this synergy. Cultured PBMC were exposed to each pesticide in the presence of LPS, P4, or their combination. TNF-α was measured by ELISA. All pesticides enhanced TNF-α synthesis in PBMC. Co-exposure with LPS synergizes TNF-α production, which is blocked by progesterone. These results indicate that these organochlorines act synergistically with LPS to induce TNF-α secretion in PBMC. This effect is blocked by P4.


Assuntos
DDT , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos , Progesterona/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Adulto , DDT/agonistas , DDT/farmacocinética , DDT/toxicidade , Feminino , Humanos , Leucócitos Mononucleares/patologia , Lipopolissacarídeos/agonistas , Lipopolissacarídeos/toxicidade , Malária/epidemiologia , Malária/metabolismo , Malária/patologia , Gravidez , Complicações Parasitárias na Gravidez/epidemiologia , Complicações Parasitárias na Gravidez/metabolismo , Complicações Parasitárias na Gravidez/patologia
6.
Infect Immun ; 84(6): 1761-1774, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27045035

RESUMO

Plasmodium falciparum infection during pregnancy leads to abortions, stillbirth, low birth weight, and maternal mortality. Infected erythrocytes (IEs) accumulate in the placenta by adhering to chondroitin sulfate A (CSA) via var2CSA protein exposed on the P. falciparum IE membrane. Plasmodium berghei IE infection in pregnant BALB/c mice is a model for severe placental malaria (PM). Here, we describe a transgenic P. berghei parasite expressing the full-length var2CSA extracellular region (domains DBL1X to DBL6ε) fused to a P. berghei exported protein (EMAP1) and characterize a var2CSA-based mouse model of PM. BALB/c mice were infected at midgestation with different doses of P. berghei-var2CSA (P. berghei-VAR) or P. berghei wild-type IEs. Infection with 10(4) P. berghei-VAR IEs induced a higher incidence of stillbirth and lower fetal weight than P. berghei At doses of 10(5) and 10(6) IEs, P. berghei-VAR-infected mice showed increased maternal mortality during pregnancy and fetal loss, respectively. Parasite loads in infected placentas were similar between parasite lines despite differences in maternal outcomes. Fetal weight loss normalized for parasitemia was higher in P. berghei-VAR-infected mice than in P. berghei-infected mice. In vitro assays showed that higher numbers of P. berghei-VAR IEs than P. berghei IEs adhered to placental tissue. Immunization of mice with P. berghei-VAR elicited IgG antibodies reactive to DBL1-6 recombinant protein, indicating that the topology of immunogenic epitopes is maintained between DBL1-6-EMAP1 on P. berghei-VAR and recombinant DBL1-6 (recDBL1-6). Our data suggested that impairments in pregnancy caused by P. berghei-VAR infection were attributable to var2CSA expression. This model provides a tool for preclinical evaluation of protection against PM induced by approaches that target var2CSA.


Assuntos
Anticorpos Antiprotozoários/biossíntese , Antígenos de Protozoários/imunologia , Malária Falciparum/prevenção & controle , Malária/prevenção & controle , Plasmodium berghei/imunologia , Plasmodium falciparum/imunologia , Proteínas Recombinantes de Fusão/imunologia , Animais , Antígenos de Protozoários/administração & dosagem , Antígenos de Protozoários/genética , Sulfatos de Condroitina/química , Sulfatos de Condroitina/imunologia , Modelos Animais de Doenças , Epitopos/química , Epitopos/imunologia , Eritrócitos/imunologia , Eritrócitos/parasitologia , Feminino , Peso Fetal/efeitos dos fármacos , Imunização , Imunoglobulina G/biossíntese , Malária/imunologia , Malária/patologia , Malária Falciparum/imunologia , Malária Falciparum/patologia , Camundongos , Camundongos Endogâmicos BALB C , Carga Parasitária , Parasitemia/imunologia , Parasitemia/patologia , Parasitemia/prevenção & controle , Placenta , Plasmodium berghei/genética , Plasmodium falciparum/genética , Gravidez , Complicações Parasitárias na Gravidez/imunologia , Complicações Parasitárias na Gravidez/patologia , Complicações Parasitárias na Gravidez/prevenção & controle , Domínios Proteicos , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Natimorto
7.
Exp Parasitol ; 166: 116-23, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27068784

RESUMO

Congenital transmission of Toxoplasma gondii may occur if the mother gets infected for the first time while pregnant. The risk of mother-to-child transmission depends on the gestation trimester at infection, being lowest in the first and highest in the last. Conversely, fetal damage is frequent and more severe at the beginning of pregnancy. The objective of this study was to evaluate congenital transmission and pathological aspects in the placenta and the fetus using a mouse model of congenital infection of the second gestation third. Forty-five female BALB/c mice were infected intravenously with 2.5-10.0 × 10(6) tachyzoites of the ME49 strain at middle gestation. Samples of maternal spleen and fetal/placental units were taken 72 h later. We determined parasite load and vertical transmission by qPCR, as well as damage macroscopically and by histopathology. With the lowest dose, 18% of the fetuses were infected. Also, 40% of fetuses/litter were altered, while this value was 10% in the control group (P < 0.05). These results are similar to those described in humans in terms of vertical transmission and fetal damage during the second third of gestation. The maternal spleen had 10-1000 times more tachyzoites than the placenta, and the later retained 90-99% of the parasites that could reach the fetus. Nevertheless, we found resorptions, abortions or fetal tissue damage in the presence but also in the absence of parasites. Our data indicate a strong protective effect of maternal organs and the placenta against fetal infection, but extensive damage of the later may led to resorption or abortion without vertical transmission.


Assuntos
Feto/parasitologia , Transmissão Vertical de Doenças Infecciosas , Placenta/parasitologia , Complicações Parasitárias na Gravidez/parasitologia , Toxoplasmose Animal/congênito , Animais , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Perda do Embrião/parasitologia , Feminino , Feto/patologia , Hemorragia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Necrose , Carga Parasitária , Placenta/patologia , Gravidez , Complicações Parasitárias na Gravidez/patologia , Organismos Livres de Patógenos Específicos , Baço/parasitologia , Trombose , Toxoplasmose Animal/patologia , Toxoplasmose Animal/transmissão
8.
Malar J ; 14: 118, 2015 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-25889709

RESUMO

BACKGROUND: Placental malaria (PM) causes adverse pregnancy outcomes in the mother and her foetus. It is difficult to study PM directly in humans due to ethical challenges. This study set out to bridge this gap by determining the outcome of PM in non-immune baboons in order to develop a non-human primate model for the disease. METHODS: Ten pregnant baboons were acquired late in their third trimester (day 150) and randomly grouped as seven infected and three non-infected. Another group of four nulligravidae (non-pregnant) infected was also included in the analysis of clinical outcome. Malaria infection was intravenously initiated by Plasmodium knowlesi blood-stage parasites through the femoral vein on 160(th) day of gestation (for pregnant baboons). Peripheral smear, placental smear, haematological samples, and histological samples were collected during the study period. Median values of clinical and haematological changes were analysed using Kruskal-Wallis and Dunn's Multiple Comparison Test. Parasitaemia profiles were analysed using Mann Whitney U test. A Spearman's rank correlation was run to determine the relationship between the different variables of severity scores. Probability values of P <0.05 were considered significant. RESULTS: Levels of white blood cells increased significantly in pregnant infected (34%) than in nulligravidae infected baboons (8%). Placental parasitaemia levels was on average 19-fold higher than peripheral parasitaemia in the same animal. Infiltration of parasitized erythrocytes and inflammatory cells were also observed in baboon placenta. Malaria parasite score increased with increase in total placental damage score (rs = 0.7650, P <0.05) and inflammatory score (rs = 0.8590, P <0.05). Although the sample size was small, absence of parasitized erythrocytes in cord blood and foetal placental region suggested lack of congenital malaria in non-immune baboons. CONCLUSION: This study has demonstrated accumulation of parasitized red blood cells and infiltration of inflammatory cells in the placental intravillous space (IVS) of baboons that are non-immune to malaria. This is a key feature of placental falciparum malaria in humans. This presents the baboon as a new model for the characterization of malaria during pregnancy.


Assuntos
Modelos Animais de Doenças , Papio anubis , Placenta/parasitologia , Plasmodium knowlesi/fisiologia , Complicações Parasitárias na Gravidez/parasitologia , Animais , Feminino , Testes Hematológicos , Humanos , Teste de Papanicolaou , Parasitemia/parasitologia , Parasitemia/patologia , Placenta/patologia , Gravidez , Complicações Parasitárias na Gravidez/patologia
9.
Exp Parasitol ; 154: 51-61, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25913086

RESUMO

Congenital toxoplasmosis may result in abortion, severe mental retardation and neurologic damage in the offspring. Placental damage is considered as the key event in this disease. Here we show that maternal infection with Toxoplasma gondii Wh3 isolate of genotype Chinese 1, which is predominantly prevalent in China, induced trophoblast apoptosis of pregnant mouse. PCR array analysis of 84 key genes in the biogenesis and functions of mouse mitochondrion revealed that ten genes were up-regulated at least 2-fold in the Wh3 infection group, compared with those in the control. The elevated levels of reactive oxygen species (ROS), malondialdehyde (MDA) and 8-hydroxydeoxyguanosine (8-OHdG), as well as the decreased glutathione (GSH), were observed in the infected mice. The mRNA levels of NADPH oxidase 1 and glutathione peroxidase 6 (GPx6) were significantly increased. The production of excessive ROS was NADPH oxidase-dependent, which contributed to mitochondrial structural damage and mitochondrial dysfunction in placentas, followed by the cleavage of caspase-9 and caspase-3, and finally resulted in apoptosis of trophoblasts. All the above-mentioned phenomena were inhibited by pretreatment with the antioxidant of N-acetylcysteine (NAC). Taken together, we concluded that Wh3 infection during pregnancy may contribute to trophoblast apoptosis by oxidative stress-induced mitochondrial dysfunction and activation of the downstream signaling pathway.


Assuntos
Complicações Parasitárias na Gravidez/patologia , Toxoplasma/fisiologia , Toxoplasmose Animal/patologia , Trofoblastos/patologia , Animais , Apoptose , Feminino , Genótipo , Masculino , Potenciais da Membrana , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/patologia , Mitocôndrias/fisiologia , Estresse Oxidativo , Placenta/metabolismo , Placenta/fisiopatologia , Gravidez , Complicações Parasitárias na Gravidez/metabolismo , Complicações Parasitárias na Gravidez/parasitologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasmose Animal/metabolismo , Toxoplasmose Animal/parasitologia , Transcriptoma
10.
Exp Parasitol ; 156: 32-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26028409

RESUMO

Bovine tritrichomonosis is a sexually transmitted disease caused by the protozoon Tritrichomonas foetus and characterised by embryonic-death and abortion. During pregnancy, the processes of cell proliferation and death play a crucial role for blastocyst implantation and the subsequent maintenance of early pregnancy, and their misbalance may lead to the abortion. In this study, we aimed to investigate whether cell proliferation and death may be altered during tritrichomonosis. For this purpose, we used pregnant BALB/c mice as an alternative experimental animal model that has successfully reproduced the infection. We analysed the immunohistochemical expression of active caspase-3 and proliferating cell nuclear (PCNA) antigens in the endometrium of infected mice. We found an increase in the number of caspase-3 positive cells in infected mice that were not pregnant at the necropsy. Besides, the number of positive proliferating cells increased in the uterine luminal epithelium of infected animals killed at 5-7 days post coitum (dpc). Pregnant infected mice killed at 8-11 dpc showed higher proliferation than control animals. We suggest that the cytopathic effect induced by T. foetus in the uteri of infected mice may induce the apoptosis of the epithelial cells and, as a result, promote a compensatory proliferative response. The information described here will be helpful to further study the pathogenesis of the bovine tritrichomonosis.


Assuntos
Doenças dos Bovinos/patologia , Perda do Embrião/veterinária , Complicações Parasitárias na Gravidez/veterinária , Infecções Protozoárias em Animais/patologia , Tritrichomonas foetus/patogenicidade , Animais , Apoptose , Caspase 3/análise , Bovinos , Doenças dos Bovinos/mortalidade , Doenças dos Bovinos/parasitologia , Proliferação de Células , Modelos Animais de Doenças , Perda do Embrião/parasitologia , Perda do Embrião/patologia , Feminino , Doenças Fetais/mortalidade , Doenças Fetais/patologia , Doenças Fetais/veterinária , Imuno-Histoquímica/veterinária , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Gravidez , Complicações Parasitárias na Gravidez/mortalidade , Complicações Parasitárias na Gravidez/patologia , Infecções Protozoárias em Animais/mortalidade , Útero/enzimologia , Útero/patologia
11.
Parasitol Res ; 114(1): 193-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25324135

RESUMO

The water buffalo (Bubalus bubalis) is an important species in several countries for its milk and meat production, as well as for transport and other agricultural activities. It is, in general, considered more resistant than cattle to different parasitic diseases, also less demanding for forage quality. It has been postulated that buffalo may be resistant to abortion caused by neosporosis, because of high serological prevalences found in buffalo herds from different localities, with no description of Neospora caninum-related abortion. Recent studies have demonstrated the potential impact of neosporosis in pregnant water buffalo cows. In this work, three pregnant buffalo cows were experimentally infected with Nc-1 strain of N. caninum, and abortion was detected 35 days post-infection. Molecular and histopathological results found in post-mortem tissues are described and discussed, confirming the susceptibility of water buffalos to abortion caused by N. caninum.


Assuntos
Aborto Animal/parasitologia , Feto/parasitologia , Neospora , Complicações Parasitárias na Gravidez/veterinária , Animais , Búfalos/parasitologia , Bovinos , Coccidiose/veterinária , Feminino , Feto/patologia , Gravidez , Complicações Parasitárias na Gravidez/patologia
12.
J Infect Dis ; 209(3): 468-72, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23964108

RESUMO

Schistosomiasis affects approximately 40 million women of reproductive age and has been linked to elevated levels of circulating endotoxin in nonpregnant individuals. We have evaluated endotoxin levels in maternal, placental, and newborn blood collected from women residing in Leyte, Philippines. Endotoxin levels in both maternal and placental compartments in pregnant women with schistosomiasis were 1.3- and 2.4-fold higher, respectively, than in uninfected women. In addition, higher concentrations of endotoxin in placental blood were associated with premature birth, acute chorioamnionitis, and elevated proinflammatory cytokines. By promoting endotoxemia, schistosomiasis may exert additional, maladaptive influences on pregnancy outcomes.


Assuntos
Análise Química do Sangue , Endotoxinas/sangue , Sangue Fetal/química , Complicações Parasitárias na Gravidez/patologia , Esquistossomose Japônica/patologia , Adulto , Citocinas/sangue , Feminino , Humanos , Recém-Nascido , Filipinas , Gravidez
13.
J Clin Microbiol ; 52(9): 3468-70, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24989613

RESUMO

We report a rare and unusual case of invasive Enterobius vermicularis infection in a fallopian tube. The patient was a 23-year-old Malaysian woman who presented with suprapubic pain and vaginal bleeding. A clinical diagnosis of ruptured right ovarian ectopic pregnancy was made. She underwent a laparotomy with a right salpingo-oophorectomy. Histopathological examination of the right fallopian tube showed eggs and adult remnants of E. vermicularis, and the results were confirmed using PCR and DNA sequencing.


Assuntos
Enterobíase/diagnóstico , Enterobius/isolamento & purificação , Complicações Parasitárias na Gravidez/diagnóstico , Gravidez Ectópica/diagnóstico , Salpingite/diagnóstico , Animais , DNA de Helmintos/química , DNA de Helmintos/genética , Enterobíase/patologia , Enterobíase/cirurgia , Tubas Uterinas/parasitologia , Tubas Uterinas/patologia , Feminino , Histocitoquímica , Humanos , Laparoscopia , Malásia , Ovariectomia , Reação em Cadeia da Polimerase , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Complicações Parasitárias na Gravidez/patologia , Complicações Parasitárias na Gravidez/cirurgia , Salpingectomia , Salpingite/parasitologia , Salpingite/patologia , Salpingite/cirurgia , Análise de Sequência de DNA , Adulto Jovem
15.
Biol Reprod ; 88(6): 154, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23575149

RESUMO

During pregnancy, Plasmodium falciparum-infected erythrocytes cytoadhere to the placenta. Infection is likely initiated at two sites where placental trophoblasts contact maternal blood: 1) via syncytiotrophoblast (STB), a multicellular transporting and biosynthetic layer that forms the surface of chorionic villi and lines the intervillous space, and 2) through invasive cytotrophoblasts, which line uterine vessels that divert blood to the placenta. Here, we investigated mechanisms of infected erythrocyte sequestration in relationship to the microanatomy of the maternal-fetal interface. Histological analyses revealed STB denudation in placental malaria, which brought the stromal cores of villi in direct contact with maternal blood. STB denudation was associated with hemozoin deposition (P = 0.01) and leukocyte infiltration (P = 0.001) and appeared to be a feature of chronic placental malaria. Immunolocalization of infected red blood cell receptors (CD36, ICAM1/CD54, and chondroitin sulfate A) in placentas from uncomplicated pregnancies showed that STB did not stain, while the underlying villous stroma was immunopositive. Invasive cytotrophoblasts expressed ICAM1. In malaria, STB denudation exposed CD36 and chondroitin sulfate A in the villous cores to maternal blood, and STB expressed ICAM1. Finally, we investigated infected erythrocyte adherence to novel receptors by screening an array of 377 glycans. Infected erythrocytes bound Lewis antigens that immunolocalized to STB. Our results suggest that P. falciparum interactions with STB-associated Lewis antigens could initiate placental malaria. Subsequent pathologies, which expose CD36, ICAM1, and chondroitin sulfate A, might propagate the infection.


Assuntos
Eritrócitos/parasitologia , Malária Falciparum/metabolismo , Placenta/parasitologia , Plasmodium falciparum/isolamento & purificação , Complicações Parasitárias na Gravidez/metabolismo , Trofoblastos/parasitologia , Adulto , Antígenos CD36/metabolismo , Sulfatos de Condroitina/metabolismo , Vilosidades Coriônicas/metabolismo , Vilosidades Coriônicas/parasitologia , Vilosidades Coriônicas/patologia , Eritrócitos/metabolismo , Eritrócitos/patologia , Feminino , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Malária Falciparum/patologia , Placenta/metabolismo , Gravidez , Complicações Parasitárias na Gravidez/patologia , Trofoblastos/metabolismo , Trofoblastos/patologia
16.
J Infect Dis ; 206(12): 1904-10, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23053630

RESUMO

BACKGROUND: Evidence of the presence of Plasmodium vivax in the placenta is scarce and inconclusive. This information is relevant to understanding whether P. vivax affects placental function and how it may contribute to poor pregnancy outcomes. METHODS: Histopathologic examination of placental biopsies from 80 Papua New Guinean pregnant women was combined with quantitative polymerase chain reaction (qPCR) to confirm P. vivax infection and rule out coinfection with other Plasmodium species in placental and peripheral blood. Leukocytes and monocytes/macrophages were detected in placental sections by immunohistochemistry. RESULTS: Monoinfection by P. vivax and Plasmodium falciparum was detected by qPCR in 8 and 10 placentas, respectively. Seven of the 8 women with P. vivax placental monoinfection were negative in peripheral blood. By histology, 3 placentas with P. vivax monoinfection showed parasitized erythrocytes in the intervillous space but no hemozoin in macrophages nor increased intervillous inflammatory cells. In contrast, 7 placentas positive for P. falciparum presented parasites and hemozoin in macrophages or fibrin as well as intervillous inflammatory infiltrates. CONCLUSIONS: Plasmodium vivax can be associated with placental infection. However, placental inflammation is not observed in P. vivax monoinfections, suggesting other causes of poor delivery outcomes associated with P. vivax infection.


Assuntos
Malária Vivax/patologia , Malária Vivax/parasitologia , Placenta/patologia , Placenta/parasitologia , Plasmodium vivax/isolamento & purificação , Plasmodium vivax/patogenicidade , Complicações Parasitárias na Gravidez/patologia , Adolescente , Adulto , Biópsia , Feminino , Histocitoquímica , Humanos , Imuno-Histoquímica , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
17.
J Immunol ; 185(11): 7115-22, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20980627

RESUMO

Plasmodium falciparum-infected erythrocytes (IEs) sequester in the intervillous space (IVS) of the placenta causing placental malaria (PM), a condition that increases a woman's chances of having a low-birth-weight baby. Because IEs sequester, they frequently are not observed in peripheral blood smears, resulting in women with PM being misdiagnosed and thus not treated. Because sequestered IEs induce inflammation in the IVS, detection of inflammatory mediators in the peripheral blood may provide an approach for diagnosing PM. Two counterregulatory molecules, TNF-αR (TNFR) 1 and TNFR2, modulate the pathological effects of TNF-α. Levels of these soluble TNFRs (sTNFRs) are reported to be elevated in children with severe malaria, but it is unclear if they are increased in the peripheral blood of PM-positive women with asymptomatic infections. In this study, sTNFR levels were measured throughout the course of pregnancy, as well as at delivery, in women with asymptomatic infections and those who remained uninfected. Results showed that both sTNFRs were significantly increased in the peripheral blood of women with asymptomatic malaria (p < 0.0001) and were positively correlated with parasitemia (p < 0.0001 for sTNFR1 and p = 0.0046 for sTNFR2). Importantly, levels of sTNFR2 were elevated in the peripheral blood of women who were PM-positive but peripheral blood-smear negative (p = 0.0017). Additionally, sTNFR2 levels were elevated in the blood of malaria-positive women who delivered low-birth-weight babies. In vitro studies demonstrated that syncytiotrophoblasts were not a major source of sTNFR. These data suggest that sTNFR2 may be a valuable biomarker for detection of malaria-associated inflammation.


Assuntos
Mediadores da Inflamação/sangue , Malária/imunologia , Malária/patologia , Plasmodium falciparum/imunologia , Complicações Parasitárias na Gravidez/imunologia , Receptores Tipo II do Fator de Necrose Tumoral/biossíntese , Receptores Tipo I de Fatores de Necrose Tumoral/biossíntese , Biomarcadores/sangue , Estudos de Coortes , Feminino , Humanos , Recém-Nascido de Baixo Peso/imunologia , Recém-Nascido , Mediadores da Inflamação/fisiologia , Malária/parasitologia , Valor Preditivo dos Testes , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Complicações Parasitárias na Gravidez/patologia , Estudos Prospectivos , Receptores Tipo I de Fatores de Necrose Tumoral/sangue , Receptores Tipo II do Fator de Necrose Tumoral/sangue , Regulação para Cima/imunologia
18.
Exp Parasitol ; 131(2): 215-22, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22542801

RESUMO

Malarial infection during pregnancy has been associated with maternal anemia and death, abortion, still-birth and is a major cause of low birth weight, an important risk factor for infant morbidity and mortality in endemic areas. The present study was designed to delineate the oxidative stress in various organs (liver, spleen, kidney, brain and placenta) of pregnant Plasmodium berghei infected BALB/c mice. It was observed that pregnant-infected mice had higher parasitaemia than nonpregnant-infected mice. Most notably, levels of malondialdehyde (MDA), a measure of lipid peroxidation, reduced glutathione (GSH) and superoxide dismutase (SOD) levels were significantly higher in the liver, spleen, kidney and brain of pregnant-infected mice compared with pregnant mice. Although MDA levels were significantly higher, GSH and SOD levels remained unaltered in the placenta of pregnant-infected mice compared with pregnant mice. Furthermore, catalase activity was significantly lower in all the organs of pregnant-infected mice compared with pregnant mice. Histopathological observations in the organs clearly show the cellular and morphological alterations that may be occurring due to increased lipid peroxidation. Taken together, the data suggest that the increased severity of malarial infection during pregnancy may be due to accentuated oxidative stress.


Assuntos
Malária/metabolismo , Estresse Oxidativo/fisiologia , Plasmodium berghei , Complicações Parasitárias na Gravidez/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Catalase/análise , Feminino , Glutationa/análise , Rim/metabolismo , Rim/patologia , Peroxidação de Lipídeos , Fígado/metabolismo , Fígado/patologia , Malária/patologia , Malondialdeído/análise , Camundongos , Camundongos Endogâmicos BALB C , Parasitemia/metabolismo , Parasitemia/parasitologia , Parasitemia/patologia , Placenta/metabolismo , Placenta/patologia , Gravidez , Complicações Parasitárias na Gravidez/patologia , Índice de Gravidade de Doença , Baço/metabolismo , Baço/patologia , Superóxido Dismutase/análise
19.
Placenta ; 127: 52-61, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35970103

RESUMO

INTRODUCTION: Pregnant women are more susceptible to malaria due to a combination of physiological and immunological changes. The infection may even affect the growth and survival of the foetus, which mainly occur when parasite enters the placenta. The sequestration of infected erythrocytes may trigger the host response, leading to placental inflammation and altered development, affecting the structure and nutrient transport of placenta. These factors collectively impair placental functions and affect foetal growth. METHODS: Pregnant women with peripheral parasitaemia for P. falciparum and P. vivax (20 each) were included in the present study, along with 15 age-matched uninfected healthy pregnant women. Placentae were analysed for the presence of local parasitaemia along with pathological lesions caused due to the parasite. Immunohistochemical staining for CD20, CD45 and CD68 cells was performed for examining the specific leucocytes in the intervillous space of the placenta. RESULTS: Of the 20 individuals with P. falciparum, only seven placentae showed parasitaemia, whereas individuals with P. vivax showed no placental infection. The pathological changes observed in the P. falciparum-infected placenta include syncytial knotting, excess fibrinoid deposition, syncytiotrophoblast necrosis, syncytial rupture, thickening of trophoblast basement membrane and increased collagen deposition. Immunohistochemical staining showed a significant increase in B cells (CD20), leucocytes (CD45) and monocytes and macrophages (CD68) in the P. falciparum-infected placenta (p < 0.0001). DISCUSSION: The result implies that P. falciparum is responsible for pathological alterations in placenta, affecting the nutrient transport across placenta and foetal growth. The immune cells also migrate to the placenta and accumulate in the intervillous space to show humoral and cell-mediated immunity against the parasite.


Assuntos
Malária Falciparum , Malária , Complicações Parasitárias na Gravidez , Feminino , Humanos , Macrófagos/patologia , Monócitos/patologia , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Complicações Parasitárias na Gravidez/patologia
20.
Infect Immun ; 79(3): 1254-61, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21149589

RESUMO

Schistosomes infect ∼40 million women of childbearing age and result in the elaboration of proinflammatory cytokines that have been implicated in fetal growth restriction. In murine models and two observational studies in humans, schistosome infection during pregnancy was associated with reduced birth weight, although a recent treatment trial in Schistosoma mansoni did not detect this association. We conducted an observational study among 99 pregnant women living in an area of Schistosoma japonicum endemicity in the Philippines. We enrolled women at 32 weeks gestation and measured S. japonicum and geohelminth infection intensity. We collected maternal peripheral blood at 32 weeks gestation and placental and cord blood at delivery to assess inflammatory status. At delivery, we collected a placental-tissue sample and measured birth weight. In multivariate models adjusted for geohelminths, maternal schistosomiasis was associated with increased levels of inflammatory cytokines in maternal peripheral (tumor necrosis factor alpha [TNF-α] and interleukin 10 [IL-10]), placental (TNF-α, IL-6, TNF-α receptor II [RII], and IL-1ß), and cord (IL-1ß and TNF-α RII) blood, as well as acute subchorionitis and increased TNF-α production by syncytiotrophoblasts assessed by immunohistochemistry (all P < 0.05). After adjusting for confounders, placental IL-1ß, and TNF-α production by syncytiotrophoblasts was independently associated with decreased birth weight (both P < 0.05). Our data indicate that maternal schistosomiasis results in a proinflammatory signature that is detectable in maternal, placental, and fetal compartments, and a subset of these responses are associated with decreased birth weight. This potential mechanistic link between maternal schistosomiasis and poor birth outcomes will contribute to the debate regarding treatment of maternal schistosome infections.


Assuntos
Doenças Fetais/patologia , Doenças Fetais/parasitologia , Inflamação/patologia , Placenta/patologia , Complicações Parasitárias na Gravidez/patologia , Schistosoma japonicum/fisiologia , Esquistossomose Japônica/patologia , Adulto , Animais , Peso ao Nascer , Feminino , Doenças Fetais/imunologia , Feto , Humanos , Inflamação/sangue , Inflamação/imunologia , Filipinas , Gravidez , Complicações Parasitárias na Gravidez/sangue , Complicações Parasitárias na Gravidez/imunologia , Esquistossomose Japônica/sangue , Esquistossomose Japônica/imunologia
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