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1.
Anim Genet ; 44(5): 509-21, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23714019

RESUMO

The aims of this study were to assess the genetic diversity of 17 populations of Vietnamese local chickens (VNN) and one Red Jungle Fowl population, together with six chicken populations of Chinese origin (CNO), and to provide priorities supporting the conservation of genetic resources using 20 microsatellites. Consequently, the VNN populations exhibited a higher diversity than did CNO populations in terms of number of alleles but showed a slightly lower observed heterozygosity. The VNN populations showed in total seven private alleles, whereas no CNO private alleles were found. The expected heterozygosity of 0.576 in the VNN populations was higher than the observed heterozygosity of 0.490, leading to heterozygote deficiency within populations. This issue could be partly explained by the Wahlund effect due to fragmentation of several populations between chicken flocks. Molecular analysis of variance showed that most of genetic variation was found within VNN populations. The Bayesian clustering analysis showed that VNN and CNO chickens were separated into two distinct groups with little evidence for gene flow between them. Among the 24 populations, 13 were successfully assigned to their own cluster, whereas the structuring was not clear for the remaining 11 chicken populations. The contributions of 24 populations to the total genetic diversity were mostly consistent across two approaches, taking into account the within- and between-populations genetic diversity and allelic richness. The black H'mong, Lien Minh, Luong Phuong and Red Jungle Fowl were ranked with the highest priorities for conservation according to Caballero and Toro's and Petit's approaches. In conclusion, a national strategy needs to be set up for Vietnamese chicken populations, with three main components: conservation of high-priority breeds, within-breed management with animal exchanges between flocks to avoid Wahlund effect and monitoring of inbreeding rate.


Assuntos
Galinhas/genética , Variação Genética , Animais , Galinhas/classificação , Conservação dos Recursos Naturais , Genética Populacional , Repetições de Microssatélites , Vietnã
2.
J Evol Biol ; 25(6): 1060-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22487207

RESUMO

We studied lifetime male virility, a male fitness component, in five populations of Drosophila melanogaster. Virility was measured as the number of females, of eight total, that a male could fertilize in 24 h. Individual males were measured at weekly intervals until they died. Virility declined in an approximately linear fashion for the first 3 weeks of adult life. It then stayed low but relatively constant for another 3 weeks, exhibiting a clear plateau. These observations are consistent with the evolutionary theories of late life. The results were not consistent with a simple heterogeneity theory of late life. This is the first demonstration of a late-life plateau for a male fitness component. We also found that the virility of males that were within 7 days of death was significantly lower than that of similarly aged males that were not about to die. This rapid deterioration of virility prior to death, or death spiral, is similar to a decline in fecundity that we had previously documented.


Assuntos
Drosophila melanogaster/fisiologia , Evolução Molecular , Aptidão Genética , Estágios do Ciclo de Vida , Fatores Etários , Animais , Cruzamento/métodos , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Feminino , Fertilidade , Deriva Genética , Heterogeneidade Genética , Longevidade , Masculino , Modelos Estatísticos , Fatores de Tempo
3.
Microorganisms ; 10(10)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36296279

RESUMO

The Brucella species is the causative agent of brucellosis in humans and animals. So far, brucellosis has caused considerable economic losses and serious public health threats. Furthermore, Brucella is classified as a category B bioterrorism agent. Although the mortality of brucellosis is low, the pathogens are persistent in mammalian hosts and result in chronic infection. Brucella is a facultative intracellular bacterium; hence, it has to invade different professional and non-professional phagocytes through the host phagocytosis mechanism to establish its lifecycle. The phagocytosis of Brucella into the host cells undergoes several phases including Brucella detection, formation of Brucella-containing vacuoles, and Brucella survival via intracellular growth or being killed by host-specific bactericidal activities. Different host surface receptors contribute effectively to recognize Brucella including non-opsonic receptors (toll-like receptors and scavenger receptor A) or opsonic receptors (Fc receptors and complement system receptors). Brucella lacks classical virulence factors such as exotoxin, spores, cytolysins, exoenzymes, virulence plasmid, and capsules. However, once internalized, Brucella expresses various virulence factors to avoid phagolysosome fusion, bypass harsh environments, and establish a replicative niche. This review provides general and updated information regarding Brucella phagocytosis mediated by pathogen-host interactions and their intracellular survival in host cells.

4.
Pathogens ; 11(5)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35631117

RESUMO

The effects of Cobalt (II) chloride (CoCl2) in the context of Brucella abortus (B. abortus) infection have not been evaluated so far. Firstly, we found that CoCl2 treatment inhibited the phagocytosis of B. abortus into RAW 264.7 cells. The inhibition of bacterial invasion was regulated by F-actin formation and associated with a reduction in the phosphorylation of ERK1/2 and HIF-1α expression. Secondly, the activation of trafficking regulators LAMP1, LAMP2, and lysosomal enzyme GLA at the transcriptional level activated immune responses, weakening the B. abortus growth at 4 h post-infection (pi). The silencing of HIF-1α increased bacterial survival at 24 h pi. At the same time, CoCl2 treatment showed a significant increase in the transcripts of lysosomal enzyme HEXB and cytokine TNF-α and an attenuation of the bacterial survival. Moreover, the enhancement at the protein level of HIF-1α was induced in the CoCl2 treatment at both 4 and 24 h pi. Finally, our results demonstrated that CoCl2 administration induced the production of serum cytokines IFN-γ and IL-6, which is accompanied by dampened Brucella proliferation in the spleen and liver of treated mice, and reduced the splenomegaly and hepatomegaly. Altogether, CoCl2 treatment contributed to host resistance against B. abortus infection with immunomodulatory effects.

5.
BJOG ; 117(8): 1027-30, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20465557

RESUMO

In this retrospective study of 314 patients undergoing surgery for ovarian dermoid cysts, conducted over a 20-year period, we evaluated the impact of the routine use of laparoscopic surgery without recourse to laparotomy to retrieve the specimen, using an endoscopic retrieval bag placed under the cyst to prevent intraperitoneal spillage of cyst contents, and subsequent postoperative granulomatous peritonitis. Accidental cyst rupture was more frequent when a total laparoscopic approach was used (26/174 or 15% versus 39/140 or 28%; P = 0.005), but there were no cases of intraperitoneal spillage when an endoscopic bag was used. Two cases of granulomatous peritonitis developed out of 26 women with intraperitoneal spillage of cyst contents (8%). We conclude that the risk of granulomatous peritonitis can be minimised by undertaking laparoscopic removal of dermoid cysts with the routine intraoperative use of an endoscopic retrieval bag to prevent intraperitoneal spillage of cyst contents.


Assuntos
Cisto Dermoide/cirurgia , Laparoscopia/métodos , Neoplasias Ovarianas/cirurgia , Peritonite/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Manejo de Espécimes/métodos , Adulto Jovem
6.
Artigo em Inglês | MEDLINE | ID: mdl-30186773

RESUMO

The cellular oncogene c-Fos (c-Fos) is a component of activator protein 1 (AP1), a master transcriptional regulator of cells. The suppression of c-Fos signaling by siRNA treatment resulted in significant induction of TLR4, which subsequently activates p38 and ERK1/2 mitogen-activated protein kinases (MAPKs) and enhances F-actin polymerization, leading to an increase in B. abortus phagocytosis. During B. abortus infection, c-Fos signaling is induced, which activates the downstream innate-immunity signaling cascade for bacterial clearance. The inhibition of c-Fos signaling led to increased production of interleukin 10 (IL-10), which partially suppressed lysosome-mediated killing, resulting in increased survival of B. abortus inside macrophages. We present evidence of the regulatory role played by the c-Fos pathway in proliferation during B. abortus infection; however, this was independent of the anti-Brucella effect of this pathway. Another finding is the essential contribution of c-Fos/TRAIL to infected-cell necrosis, which is a key event in bacterial dissemination. These data provide the mechanism via which c-Fos participates in host defense mechanisms against Brucella infection and in bacterial dissemination by macrophages.


Assuntos
Brucella/crescimento & desenvolvimento , Brucella/imunologia , Interações Hospedeiro-Patógeno , Macrófagos/imunologia , Macrófagos/microbiologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Animais , Sobrevivência Celular , Camundongos , Células RAW 264.7
7.
J Vet Sci ; 19(1): 51-57, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-28693306

RESUMO

Brucellosis is an emerging infectious disease affecting humans and animals. In this study, we investigated the in vitro and in vivo effects of tannic acid (TA) against Brucella abortus infection. After infection, F-actin polymerization and mitogen-activated protein kinases (MAPKs) (ERK 1/2 and p38α) phosphorylation were reduced in TA-treated cells compared with that in control cells. The mice were infected via an intraperitoneal route and were orally given TA or phosphate-buffered saline for 14 days. Spleen weights of the TA-treated and control mice were not different; however, splenic proliferation of B. abortus was significantly reduced in the TA-treated group. Immune response analysis showed that, compared with the control group, non-infected TA-treated mice displayed increased levels of interferon-γ (IFN-γ), monocyte chemoattractant protein-1 (MCP-1), and interleukin-10 at 3 days post-infection and a further increase in IFN-γ and MCP-1 at 14 days post-infection. In contrast, compared with the control group, infected TA-treated mice displayed elevated levels of IFN-γ at 3 days post-infection, which continued to increase at 14 days post-infection, as was also observed for tumor necrosis factor. Taken together, the results showing TA activation of cytokine production and inhibition of bacterial proliferation in the host highlight a potential use of TA treatment in the control of Brucella infection.


Assuntos
Antibacterianos/farmacologia , Brucella abortus/efeitos dos fármacos , Brucelose/imunologia , Imunidade Inata , Taninos/farmacologia , Animais , Brucelose/microbiologia , Feminino , Camundongos , Camundongos Endogâmicos ICR , Organismos Livres de Patógenos Específicos , Baço/microbiologia
8.
Bull Soc Pathol Exot ; 100(2): 99-100, 2007 May.
Artigo em Francês | MEDLINE | ID: mdl-17727028

RESUMO

A pilot study was carried out in May-June 2003 to evaluate the epidemiological situation of cryptosporidiosis in the Cu Chi district, a rural zone of Ho-Chi-Minh City Vietnam. The modified acid-fast stain of the stools revealed that 10/202 (5%) cows, 1/29 (3.5%) cattle breeders, and 2/53 (3.8%) under five year- old children with diarrhoea were infected by this germ. Unconfined cattle had a significantly higher risk of infection than penned animals (odds ratio [OR]: 8.3; 95% confidence interval [CI]: 1.06-64.7; p: 0.025).


Assuntos
Doenças dos Bovinos/epidemiologia , Criptosporidiose/epidemiologia , Criptosporidiose/veterinária , Animais , Bovinos , Diarreia Infantil/parasitologia , Humanos , Lactente , Saúde da População Rural , Vietnã/epidemiologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-29062811

RESUMO

In this study, we explore the regulatory roles of pro-inflammatory cytokine tumor necrosis factor alpha (TNF) in the innate immunity of macrophages against B. abortus infection. We show that infection of macrophage with B. abortus induces marked expression and secretion of TNF which subsequently binds to TNF receptor 1 (TNFR-1) and activates a downstream signaling cascade of the innate immunity. Blocking of TNF signaling resulted in a notable increase of B. abortus survival which was associated with an increase of anti-inflammatory cytokine interleukin 10 (IL-10), a beneficial effector of Brucella survival, as well as remarkable decrease of reactive oxygen species (ROS) and nitric oxide (NO), antibrucella molecules. However, surprisingly, the interference of TNF did not show any influence on phagolysosome and cell death events. Furthermore, the transcriptional factor NF-kB was found to be a main mediator of TNF signaling when blocking of NF-kB pathway drastically suppressed the TNF-induced brucellacidal effect. Taken together, these findings clearly indicate that the immune cascade activated by TNF/TNFR-1 is required for the sufficient resistance to B. abortus survival in macrophages.


Assuntos
Brucella abortus/imunologia , Brucelose/imunologia , Imunidade Inata , NF-kappa B/imunologia , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Animais , Morte Celular/imunologia , Humanos , Interleucina-10/imunologia , Camundongos , Óxido Nítrico/imunologia , Fagossomos/imunologia , Células RAW 264.7 , Espécies Reativas de Oxigênio/imunologia
14.
J Dent Res ; 91(12): 1166-71, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22983409

RESUMO

In cases of pulp injury, capping materials are used to enhance tertiary dentin formation; Ca(OH)(2) and MTA are the current gold standards. The aim of this study was to evaluate the capacity of a new calcium-silicate-based restorative cement to induce pulp healing in a rat pulp injury model. For that purpose, cavities with mechanical pulp exposure were prepared on maxillary first molars of 27 six-week-old male rats, and damaged pulps were capped with either the new calcium-silicate-based restorative cement (Biodentine), MTA, or Ca(OH)(2). Cavities were sealed with glass-ionomer cement, and the repair process was assessed at several time-points. At day 7, our results showed that both the evaluated cement and MTA induced cell proliferation and formation of mineralization foci, which were strongly positive for osteopontin. At longer time-points, we observed the formation of a homogeneous dentin bridge at the injury site, secreted by cells displaying an odontoblastic phenotype. In contrast, the reparative tissue induced by Ca(OH)(2) showed porous organization, suggesting a reparative process different from those induced by calcium silicate cements. Analysis of these data suggests that the evaluated cement can be used for direct pulp-capping.


Assuntos
Compostos de Cálcio/uso terapêutico , Polpa Dentária/efeitos dos fármacos , Dentina Secundária/efeitos dos fármacos , Dentinogênese/efeitos dos fármacos , Agentes de Capeamento da Polpa Dentária e Pulpectomia/uso terapêutico , Silicatos/uso terapêutico , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Compostos de Cálcio/química , Proliferação de Células/efeitos dos fármacos , Cimentos Dentários/química , Cimentos Dentários/uso terapêutico , Polpa Dentária/citologia , Restauração Dentária Permanente/métodos , Dentina Secundária/ultraestrutura , Modelos Animais de Doenças , Estudos Longitudinais , Masculino , Osteogênese/efeitos dos fármacos , Agentes de Capeamento da Polpa Dentária e Pulpectomia/química , Ratos , Silicatos/química
15.
Int J Obstet Anesth ; 21(4): 364-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22858042

RESUMO

A previously healthy 31-year-old G4P2 woman at 33 weeks of gestation was admitted as an emergency with a pyrexia of 39°C, vomiting, headache and neck stiffness associated with photophobia, phonophobia and visual and auditory symptoms. There were no heraldic signs of eclampsia. Polymerase chain reaction and testing for herpes simplex virus in the cerebrospinal fluid diagnosed herpes simplex-1 meningoencephalitis. Following acyclovir, the clinical course improved. Spontaneous vaginal delivery occurred at 39 weeks of gestation with epidural analgesia using ropivacaine. Mother and child were neurologically normal and healthy 15 months later. Early administration of acyclovir is essential to reduce the risk of neurological complications. After treatment and a negative polymerase chain reaction for herpes simplex virus in the cerebrospinal fluid, epidural analgesia with local anesthetic and sufentanil is possible.


Assuntos
Aciclovir/uso terapêutico , Encefalite por Herpes Simples/diagnóstico , Encefalite por Herpes Simples/tratamento farmacológico , Herpesvirus Humano 1/fisiologia , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Adulto , Antivirais/uso terapêutico , Encéfalo/virologia , Diagnóstico Diferencial , Encefalite por Herpes Simples/líquido cefalorraquidiano , Encefalite por Herpes Simples/virologia , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética/métodos , Reação em Cadeia da Polimerase/métodos , Gravidez , Complicações Infecciosas na Gravidez/líquido cefalorraquidiano , Complicações Infecciosas na Gravidez/virologia , Terceiro Trimestre da Gravidez , Ativação Viral
16.
Gynecol Obstet Fertil ; 39(3): e64-7, 2011 Mar.
Artigo em Francês | MEDLINE | ID: mdl-21377389

RESUMO

We report the management of spontaneous ovarian hyperstimulation syndrome in a 23-year-old patient, diagnosed at 8 gestational weeks, in a context of moderate hypothyroidism. The etiology of spontaneous ovarian hyperstimulation syndrome should seek hypersecretion of glycoprotein hormones (hCG, TSH, FSH and LH) and/or mutation of FSH and LH receptors. It will eliminate an incipient ovarian neoplasia. The laparoscopic exploration can be done if diagnosis doubt persists. A diagnostic algorithm can be proposed.


Assuntos
Hipotireoidismo/complicações , Síndrome de Hiperestimulação Ovariana/diagnóstico , Complicações na Gravidez , Dor Abdominal , Corticosteroides/uso terapêutico , Adulto , Cabergolina , Gonadotropina Coriônica/sangue , Ergolinas/uso terapêutico , Feminino , Fibrinolíticos/uso terapêutico , Hormônio Foliculoestimulante/sangue , Idade Gestacional , Doença de Graves/cirurgia , Humanos , Hipotireoidismo/tratamento farmacológico , Hormônio Luteinizante/sangue , Síndrome de Hiperestimulação Ovariana/complicações , Síndrome de Hiperestimulação Ovariana/tratamento farmacológico , Gravidez , Tireoidectomia , Tireotropina/sangue
17.
ACS Appl Mater Interfaces ; 3(9): 3515-22, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21888313

RESUMO

Two different types of clay nanoparticle hybrid, iron oxide nanoparticle clay hybrid (ICH) and Al(2)O(3)-SiO(2) nanoparticle clay hybrid (ASCH), were synthesized and their effects on the rheological properties of aqueous bentonite fluids in steady state and dynamic state were explored. When ICH particles were added, bentonite particles in the fluid cross-link to form relatively well-oriented porous structure. This is attributed to the development of positively charged edge surfaces in ICH that leads to strengthening of the gel structure of the bentonite susensions. The role of ASCH particles on the interparticle association of the bentonite fluids is different from that of ICH and sensitive to pH. As pH of ASCH-added bentonite suspensions increased, the viscosity, yield stress, storage modulus, and flow stress decreased. In contrast, at low pH, the clay suspensions containing ASCH additives were coagulated and their rheological properties become close to those of ICH added bentonite fluids. A correlation between the net surface charge of the hybrid additives and the rheological properties of the fluids indicates that the embedded nanoparticles within the interlayer space control the variable charge of the edge surfaces of the platelets and determine the particles association behavior of the clay fluids.


Assuntos
Silicatos de Alumínio/química , Bentonita/química , Nanopartículas Metálicas/química , Argila , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Reologia , Dióxido de Silício/química
18.
Gynecol Obstet Fertil ; 38(5): 347-9, 2010 May.
Artigo em Francês | MEDLINE | ID: mdl-20430677

RESUMO

We report a case of acute postcesarean colonic pseudo-obstruction (Ogilvie's syndrome). We report the treatment algorithm we followed. Recording to this algorithm may improve the treatment of this pathology and perhaps avoid surgical treatment in emergency.


Assuntos
Cesárea , Pseudo-Obstrução do Colo/diagnóstico , Pseudo-Obstrução do Colo/terapia , Adulto , Algoritmos , Colonoscopia , Feminino , Humanos , Neostigmina/uso terapêutico , Parassimpatomiméticos , Gravidez , Tomografia Computadorizada por Raios X
19.
Allergy ; 49(8): 645-52, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7653744

RESUMO

Desensitization therapy for type I allergy is now current practice. Liposomes have been proposed as a support for allergens to improve safety and effectiveness. The aim of this work was to optimize liposomal formulations of three different standardized allergen extracts and to test their allergenicity in vitro and in a preclinical trial. Allergen extracts (Dactylis glomerata, Dermatophagoides pteronyssinus, and cat hair and dander) were associated with multilamellar liposomes of varying compositions at different pH. Liposome-bound allergens were quantified by RAST inhibition after ultracentrifugation, and analyzed qualitatively by SDS-PAGE followed by immunoblotting. Their allergenicity was assessed by basophil degranulation in vitro, as compared with the allergenicity of an aqueous extract, and by skin tests in allergic subjects. The best association, about 50% of the added allergen, was obtained with negatively charged liposomes, when the pH of the allergen solution was adjusted so as to impart a net positive charge to the proteins. One-third of the liposome-associated allergens was located on the surface of the liposomes and was free to interact with antibody, as shown by RAST inhibition assays and the basophil degranulation test; the remaining two-thirds was encapsulated within the liposomes. All the major immunoreactive proteins in the extract were included. These liposomes could be readily freeze-dried and reconstituted without changing their properties. This study reveals the allergenic characteristics of liposomes and suggests their potential use in the treatment of allergic patients.


Assuntos
Alérgenos , Alérgenos/química , Alérgenos/imunologia , Aminoácidos/análise , Animais , Antígenos de Dermatophagoides , Teste de Degranulação de Basófilos , Gatos/imunologia , Portadores de Fármacos , Eletroforese em Gel de Poliacrilamida , Liofilização , Glicoproteínas/imunologia , Humanos , Hipersensibilidade/imunologia , Immunoblotting , Lipossomos , Ácaros/imunologia , Pólen/imunologia , Teste de Radioalergoadsorção
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