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1.
J Fish Dis ; 46(4): 417-431, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36651585

RESUMO

European eel is critically endangered in Europe. Among other stressors, pathogens are well-known to harm eels' fitness. One hundred and eighty-two eels were captured in three Eel Management Units in Andalucía (SE Spain) and analysed for Anguillicoloides crassus, Anguillid herpesvirus 1 (AngHV1), the rhabdovirus Eel Virus European X (EVEX) and the aquabirnavirus Eel Virus European (EVE). A. crassus adults and preadults were isolated and morphometrically identified, and the eel swimbladders were artificially digested to count A. crassus larvae. Also, eel tissues were examined by PCRs for the presence of viruses. EVEX and EVE were not detected in any of the eels. The estimated prevalence (95% confidence limits) was 71 (64-78)% for A. crassus and 35 (28-42)% for AngHV-1, varying these prevalences significantly between and within EMUs. Moreover, A. crassus prevalence was highest in smaller eels, in sites closest to the sea and eels sampled in the autumn. By contrast, AngHV-1 prevalence was highest in biggest eels, in sites far from the sea and sampled in the summer or winter. However, in mixed effects logistic models including site as a random variable, the risk of infection was associated with distance to the sea in both A. crassus and AngHV-1 infections and also to winter sampling in the case of AngHV-1 and not to other variables. These results are evidence that both pathogens are highly endemic in eels from Andalusian habitats. Further studies are needed to better understand the risk factors associated with these pathogens on eel populations.


Assuntos
Anguilla , Aquabirnavirus , Dracunculoidea , Doenças dos Peixes , Rhabdoviridae , Animais , Rhabdoviridae/genética , Espanha/epidemiologia , Doenças dos Peixes/epidemiologia , Sacos Aéreos
2.
Ir Vet J ; 69: 8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27446530

RESUMO

BACKGROUND: Identifying the aetiological agent of atypical pneumonia in human can sometimes be a tedious process, especially in cases where Mycoplasma pneumoniae, Legionella species and Chlamydia pneumoniae are ruled out. In such cases, a correct anamnesis of the patient is basic to clarify which pathogens might have produced the infection. For this reason, health professionals including veterinarians and laboratory personnel working with zoonotic pathogens should keep their doctors informed. CASE PRESENTATION: A human case of atypical pneumonia linked to Chlamydia abortus is reported. A 47-year-old male, a veterinarian researcher into chlamydiae, developed respiratory symptoms, breathing problems and high fever. Serological analyses ruled out the involvement of several respiratory pathogens, such as M. pneumoniae, Legionella pneumophila, Rickettsia conorii and C. pneumoniae, and Chlamydia abortus was identified as the possible aetiological agent of the infection. The isolation of C. abortus from the patient's sputum and subsequent molecular analysis confirmed the presence of this microorganism. CONCLUSION: As far as we know, although C. abortus has not been previously described as capable of causing pneumonia in humans, this is the first reported case of atypical pneumonia in which C. abortus is thought to have played an aetiological role.

3.
Animals (Basel) ; 13(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36978662

RESUMO

The role of lizards as potential pollinators on islands has been documented for either one or a few plants in different parts of the world, but it has never been assessed for an entire plant community. Here, we quantified interaction rate by lizards and evaluated intraspecific differences in the use of flowers on Cabrera Gran (Cabrera archipelago, Balearic Islands) by means of visual observations, automated cameras and the analysis of pollen grain samples. Overall, we recorded interactions of the Balearic wall lizard (Podarcis lilfordi) with flowers of 44 plant species, 72.7% of which were unknown to date. Although florivory occurs in some of these species (35%), the majority of visits were legitimate (65%); in addition, we found intraspecific differences in the interactions related to the sex and age of lizards. Our findings support the role of Balearic wall lizards as potential pollinators across the entire plant community, and their contribution to particular plant species, for instance the endangered Cistus heterophyllus carthaginensis. This study also documents the first record of another sympatric lizard (Tarentola mauritanica) visiting flowers and contributes to the few existing records of flower interactions involving geckos in the Paleartic ecozone.

4.
PeerJ ; 11: e15728, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520263

RESUMO

The lionfish is an exotic invasive fish native to the Indo-Pacific, which is established in the western Atlantic Ocean and the Caribbean Sea. Lionfish can affect native fishes and invertebrates through direct predation or competition for food. The present review aims to analyze the most relevant characteristics of the biology and ecology of lionfish as an invasive alien species, with an emphasis on Cuba. We provide a current view of the well-known lionfish as a successful invasive fish, and we put in this context the information regarding lionfish in Cuban waters, enriching the background knowledge, and giving novel and relevant information. The compilation of numerous publications on the subject has allowed for a more complete analysis of essential aspects of this invader in the Cuban archipelago. The consulted literature records that the first report of lionfish in Cuba occurred in 2007; subsequently, sightings of lionfish were reported in numerous localities. In 2010, the lionfish was considered an invasive alien species, which currently is established in various habitats, at depths up to 188 m, throughout the Cuban archipelago (e.g., coral reefs, mangroves, seagrass beds, submerged artificial structures). In addition, it has reached very high densities (12.42 ind./100 m2), which exceed those reported in the Indo-Pacific as well as in many locations in the Western Atlantic. It has been confirmed that the lionfish in Cuba also presents numerous characteristics that guarantee its success as an invader, among them: less quantity and diversity of parasites than other Atlantic fishes found in similar environments, a high number of gametes in the gonads, reproductive activity during all year and wide diet. The most important fish families for the lionfish diet in Cuba have been Pomacentridae, Gobiidae, Scaridae, Holocentridae, Mullidae, Labridae and Acanthuridae; and the most important crustacean orders are Decapoda, Mysida, Stomatopoda and Isopoda. In Cuba, as in the entire invaded region, numerous investigations have been directed to evaluate the impact of this invader on ecosystems, and although there is enough information, their results differ. Additional studies are required to assess the impact of lionfish as a predator after several years of invasion on a larger geographic scale in Cuba and other areas of the region. This knowledge will allow the development of more effective control strategies. Periodic lionfish culling have been carried out in Cuban MPAs as a control strategy, and some positive results have been observed, such as the average size reduction; however, further efforts are still required. Due to the importance of the study of lionfish as an invader, this review is a necessity as it provides, for the first time, a comprehensive analysis of lionfish information and results from Cuba, which is adequately contrasted with previous studies of other areas, particularly, from the Greater Caribbean.


Assuntos
Ecossistema , Perciformes , Animais , Recifes de Corais , Ecologia , Peixes , Espécies Introduzidas
5.
Pathogens ; 11(1)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35056041

RESUMO

Mice are valuable models extensively used to test vaccine candidates against Chlamydia abortus and to clarify immunopathological mechanisms of the bacteria. As this pathogen has the ability to reactivate during pregnancy, it is important to deepen the knowledge and understanding of some of the effects of female hormones on immunity and vaccination. This study is aimed at describing the role of sex hormones in the pathology of OEA during chlamydial clearance using ovariectomised mice and also gaining an understanding of how 17ß-oestradiol or progesterone may impact the effectiveness of vaccination. Animals were treated with sex hormones and infected with C. abortus, and the kinetics of infection and immune response were analysed by means of bacterial isolation, histopathology, and immunohistochemistry. In a second phase of the study, protection conferred by an experimental vaccine after hormone treatment was assessed. Oestradiol showed a stimulatory effect on the immune response during infection, with a more efficient recruitment of macrophages and T-cells at the infection site. Furthermore, after vaccination, oestradiol-treated animals showed a stronger protection against infection, indicating that this hormone has a positive effect, stimulating a specific memory response to the pathogen.

6.
PeerJ ; 10: e14250, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36389413

RESUMO

Cuba's shelf has been invaded by lionfish (Pterois volitans/Pterois miles), which have become established over the archipelago, including areas of natural importance. The present study aims to evaluate morphometric features of lionfish and to explore the relationship between lionfish size and diet composition in different habitats in the Punta Frances National Park, Cuba. In total 620 lionfish were captured at 29 sites between 2013 and 2016. Lionfish stomachs were removed and their contents were analyzed using frequency and numerical methods. The length-weight allomentric relationship was obtained, and a decrease in lionfish sizes was shown over time, likely due to the extractions carried out. The diet was composed by fishes, crustaceans, mollusks and phytobenthos, with a predominance of fishes. Lionfish caught in seagrass beds tended to be smaller in size and consumed fewer fishes and more crustaceans than those captured in coral reefs. A positive correlation was observed between lionfish body size and gape size; however, no significant correlation was detected between lionfish body size and prey size. Larger lionfish tended to consume more fishes, while crustaceans were more significant in the diet of juvenile lionfish. This is the first study that examines the feeding habits of lionfish in the Punta Frances MPA, and provides valuable information on lionfish inhabiting this MPA across four years of sampling. Furthermore, this research may serve as a baseline for subsequent evaluations of lionfish impact and management actions in the area.


Assuntos
Espécies Introduzidas , Perciformes , Animais , Cuba , Comportamento Predatório , Peixes , Dieta , França
7.
Porcine Health Manag ; 7(1): 11, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431055

RESUMO

BACKGROUND: Nutritional strategies for sows designed to reduce peripartum stress are suggested to support postpartum recovery and productivity. Spray-dried plasma (SDP) in sow feed has been reported to benefit sow and litter performance. Stressed animals fed diets with SDP have a more efficient immune response supporting animal recovery and health. The objectives of the present study using 452 sows (147 parity 1 sows, 148 parity 2 sows) were to determine if 0, 0.5 or 2.5% spray-dried porcine plasma (SDPP) in peripartum feed provided from entry in maternity through day 5 of lactation affects sow productivity and serological immune and oxidation status markers around parturition. Post-weaning sow productivity parameters including litter size at the next parturition was evaluated, but peripartum diets were only provided during the first parturition. RESULTS: In the first parturition, total born litter size was lower (P <  0.05) especially for sows allotted to the peripartum diet with 2.5% SDPP. Percentage of stillborn pigs decreased quadratically (P <  0.05) for sows fed 0.5% or 2.5% SDPP compared to 0% SDPP in peripartum feed and this result was not affected by total born litter size. Serum glutathione peroxidase activity linearly increased (P <  0.01) with increased dietary SDPP for both prepartum and postpartum sampling periods. In the next parturition, total born pigs from combined data of parity 1 and 2 sows linearly increased (P <  0.05) and live born pigs tended (P = 0.09) to linearly increase as level of SDPP increased and this result was not affected by total born litter size in the first parturition. The change in total and live born pigs from the first to the next parturition linearly (P <  0.01) increased as dietary SDPP increased for parity 1 and 2 sows. CONCLUSIONS: The reduced percentage of stillborn pigs and increased litter size of parity 1 and 2 sows in the next parturition was independent of total born litter size in the first parturition suggesting SDPP in peripartum sow feed may have merit for reducing stillborn pigs and benefit litter size in the next parturition for parity 1 and parity 2 sows.

8.
Exp Parasitol ; 126(3): 415-20, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20117109

RESUMO

The function of mitogen-activated protein kinase (MAPK) family member c-Jun N-terminal kinase (JNK)-2 in resistance and pathology during infection has not been greatly studied. Here, we employed Jnk2(-/-) mice to investigate the role of JNK2 in resistance and immunity during oral infection with the protozoan pathogen Toxoplasma gondii. We found increased host resistance in the absence of JNK2 as determined by lower parasite burden and increased host survival. Lack of JNK2 also correlated with decreased neutrophil recruitment to the intestinal mucosa and less pathology in the small intestine. In the absence of JNK2, IL-12 production was slightly but significantly increased in restimulated splenocyte populations as well as in purified splenic dendritic cell cultures. These results provide evidence that expression of JNK2 plays a role in T. gondii-induced immunopathology, at the same time in promoting susceptibility to this parasitic pathogen.


Assuntos
Proteína Quinase 9 Ativada por Mitógeno/genética , Toxoplasma/imunologia , Toxoplasmose Animal/imunologia , Animais , Encéfalo/parasitologia , Células Cultivadas , Células Dendríticas/imunologia , Suscetibilidade a Doenças , Feminino , Ileíte/parasitologia , Ileíte/patologia , Imuno-Histoquímica , Interferon gama/sangue , Interleucina-12/biossíntese , Interleucina-12/sangue , Mucosa Intestinal/citologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Intestino Delgado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Quinase 9 Ativada por Mitógeno/imunologia , Proteína Quinase 9 Ativada por Mitógeno/fisiologia , Neutrófilos/imunologia , Organismos Livres de Patógenos Específicos , Baço/citologia , Baço/imunologia , Toxoplasmose Animal/enzimologia
9.
Infect Immun ; 77(11): 4868-76, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19703981

RESUMO

The use of inactivated vaccines associated with suitable adjuvants has been demonstrated to confer a good level of protection against Chlamydophila abortus. However, the basis of the immune protective response induced by these vaccines has been poorly studied. B cells act as an immune regulatory population during primary infection by C. abortus. Thus, it was considered of interest to study the role of B cells in an infection after immunization with a killed vaccine. For this, C57BL/6 and B-cell-deficient mice were immunized with a killed vaccine against C. abortus using QS-21 as the adjuvant. After challenge, the course of infection was established by analysis of morbidity, C. abortus burden in the liver, and histopathological changes. The immune response induced was studied by real-time PCR techniques. Experiments involving transfer of immune serum from vaccinated or previously infected mice were also carried out. The lack of B cells reduced the protection conferred by the QS-21 adjuvant vaccine. Vaccinated B-cell-deficient mice showed a 1,000-fold-greater bacterial burden in the liver than their wild-type counterparts. Obvious differences existed in the liver, where a severe neutrophilic reaction and extended areas of necrosis were observed with vaccinated B-cell-deficient mice. An analysis of the immune response pointed to a significant increase in inflammatory cytokines and chemokines and the deficient production of transforming growth factor beta. The transfer of antibodies restored the level of protection. This study demonstrates that B cells play a crucial role in controlling C. abortus multiplication and prevent an exacerbated inflammatory response.


Assuntos
Linfócitos B/imunologia , Vacinas Bacterianas/farmacologia , Infecções por Chlamydophila/imunologia , Infecções por Chlamydophila/patologia , Adjuvantes Imunológicos/farmacologia , Animais , Carga Bacteriana/imunologia , Vacinas Bacterianas/imunologia , Infecções por Chlamydophila/microbiologia , Citocinas/biossíntese , Modelos Animais de Doenças , Feminino , Inflamação/imunologia , Inflamação/microbiologia , Inflamação/patologia , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saponinas/farmacologia
10.
Res Vet Sci ; 126: 199-206, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31539797

RESUMO

The obligate intracellular bacterium Chlamydia abortus causes abortion and constitutes a worldwide threat for livestock. Plant-derived flavonoids have antimicrobial effects against veterinary and human pathogens and may be of help in the fight against C. abortus. The anti-infective efficacy against C. abortus of the flavonoids apigenin and naringenin, and of four of their derived metabolites was explored using an in vitro model of ovine trophoblast cells. Overall, the anti-infective effectiveness was apigenin > naringenin > benzoic acid > 3-(4-hydroxyphenyl) propionic acid ~ 4-hydroxyphenyl acetic acid ~ 4-hydroxybenzoic. At the lowest concentration tested (10 µM), apigenin, naringenin and benzoic acid inhibited the formation of C. abortus inclusions by 80%, 67%, and 39%, respectively. The cytotoxicity and anti-proliferative effects on the trophoblast host cells also differed greatly between the tested compounds. Our findings suggest that flavonoids may be of therapeutic value against C. abortus infection but metabolic conversion has a substantial and variable effect on their anti-chlamydial activity. Our results also support the notion that the mechanisms of anti-infective action may involve combined effects of the compounds against the host cells and the bacteria.


Assuntos
Antibacterianos/farmacologia , Apigenina/farmacologia , Infecções por Chlamydia/veterinária , Chlamydia/efeitos dos fármacos , Flavanonas/farmacologia , Doenças dos Ovinos/tratamento farmacológico , Animais , Antibacterianos/metabolismo , Apigenina/metabolismo , Linhagem Celular , Infecções por Chlamydia/tratamento farmacológico , Feminino , Flavanonas/metabolismo , Ovinos , Carneiro Doméstico , Trofoblastos
11.
Otolaryngol Head Neck Surg ; 158(1): 76-82, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28895449

RESUMO

Objective To identify the risk of clinical hypocalcemia in the first hours after thyroidectomy. Study Design Prospective observational study. Setting Single-institution tertiary hospital in Madrid, Spain. Subjects and Methods A total of 123 patients who underwent total or completion thyroidectomy between June 2010 and March 2012 were included. Pre- and postoperative intact parathyroid hormone (iPTH) levels were obtained. Patients remain hospitalized a minimum of 48 hours until blood calcium stabilized. Calcium and/or vitamin D supplements were prescribed only when signs or symptoms of hypocalcemia developed. Receiver operating characteristic curve analysis was employed to evaluate the postoperative iPTH level and the pre- to postoperative decrease in iPTH levels. Two cutoff values were determined to stratify the risk of developing clinical hypocalcemia into 3 groups. Results The areas under the receiver operating characteristic curve were 0.991 for the postoperative iPTH and 0.998 for the decrease in iPTH. An iPTH decrease of 80% had 100% sensitivity to detect patients who developed clinical hypocalcemia, while a postoperative iPTH <3 pg/mL had 100% specificity. Thus, patients with an iPTH decrease ≤80% are at a very low risk of clinical hypocalcemia, and patients with a postoperative iPTH <3 pg/mL are at a very high risk. Patients with an iPTH decrease >80% and a postoperative iPTH ≥3 pg/mL are at intermediate risk. No significant correlation was found between the time when the sample was obtained and iPTH values. Conclusion This study stablishes a very accurate test to stratify the risk of clinical postthyroidectomy hypocalcemia based on pre- and postoperative iPTH levels.


Assuntos
Hipocalcemia/sangue , Hormônio Paratireóideo/sangue , Complicações Pós-Operatórias/sangue , Tireoidectomia , Biomarcadores/sangue , Cálcio/administração & dosagem , Feminino , Humanos , Hipocalcemia/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/tratamento farmacológico , Estudos Prospectivos , Fatores de Risco , Sensibilidade e Especificidade , Resultado do Tratamento
12.
Vet Microbiol ; 213: 28-34, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29292000

RESUMO

Chlamydia abortus, like other members of the family Chlamydiaceae, have a unique intracellular developmental cycle that is characterized by its chronic nature. Infection of a flock can remain undetected for months, until abortion occurs the following reproductive season but, to date, neither the location nor the mechanisms that maintain this latent phase are fully understood. Studies have shown that IL-10 produced as a response to certain micro-organisms sustains the intracellular survival of pathogens and increases host susceptibility to chlamydial infections. In order to induce a sustained infection C. abortus, transgenic mice that constitutively express IL-10 were infected and the immunological mechanisms that maintain infection in these mice were compared with the mechanisms of a resistant wild-type mouse strain. Viable bacteria could be detected in different tissues of transgenic mice up to 28 days after infection, as analysed by bacterial isolation and immunohistochemistry. Chronic infection in these mice was associated with an impaired recruitment of macrophages, decreased iNOS activity at the site of infection and a more diffuse distribution of inflammatory cells in the liver. This murine model can be of great help for understanding the immunological and bacterial mechanisms that lead to chronic chlamydial infections.


Assuntos
Infecções por Chlamydia/microbiologia , Chlamydia/imunologia , Interleucina-10/genética , Animais , Embrião de Galinha , Infecções por Chlamydia/patologia , Doença Crônica , Modelos Animais de Doenças , Feminino , Interleucina-10/metabolismo , Macrófagos/microbiologia , Camundongos , Camundongos Transgênicos
13.
J Vet Diagn Invest ; 19(4): 421-5, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17609356

RESUMO

Polymerase chain reaction (PCR) has gained increasing importance as a tool for directly demonstrating the presence of Chlamydophila in the placentas of aborted sheep and goats. However, because of the zoonotic potential of the disease, it is advisable to use fixed materials. To evaluate 4 different DNA extraction protocols in paraffin-embedded sections for PCR, previously immunohistochemically diagnosed placental samples from outbreaks of abortions in goats and sheep were used. The samples were also used to evaluate the effect of the duration of fixation in formalin on PCR. A protocol that uses Tris-HCl pH 8.5 with EDTA and subsequent digestion with proteinase K was found to be an easy protocol for obtaining excellent PCR products for Chlamydophila abortus diagnosis from formalin-fixed and paraffin-embedded specimens. It was also found that if samples are fixed in formalin for more than 2 weeks, the PCR technique is affected more adversely than immunohistochemical methods.


Assuntos
Infecções por Chlamydophila/veterinária , Chlamydophila/genética , DNA Bacteriano/isolamento & purificação , Inclusão em Parafina/veterinária , Reação em Cadeia da Polimerase/métodos , Aborto Animal/diagnóstico , Aborto Animal/microbiologia , Animais , Infecções por Chlamydophila/diagnóstico , Infecções por Chlamydophila/microbiologia , DNA Bacteriano/genética , Doenças das Cabras/diagnóstico , Doenças das Cabras/microbiologia , Cabras , Ovinos , Doenças dos Ovinos/diagnóstico , Doenças dos Ovinos/microbiologia
14.
Otol Neurotol ; 28(7): 939-41, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17704717

RESUMO

OBJECTIVE: To evaluate cyclin D1 expression in vestibular schwannoma and its relationship with histologic, clinical, and radiologic features. PATIENTS: Twenty-one patients with histologically confirmed vestibular schwannoma. INTERVENTION: Immunohistochemistry analysis was performed with anticyclin D1. Histopathologic features studied included Antoni pattern and nuclear and stromal degenerative changes. Clinical charts, audiometric data, and magnetic resonance imaging characteristics were reviewed. MAIN OUTCOME MEASURES: Cyclin D1 expression and its association with histologic, clinical, and radiologic findings. RESULTS: Cyclin D1 expression was found in 52% of cases. Cyclin D1 expression was more frequent in right-sided tumors (p = 0.02) and in tumors with nuclear degenerative changes (p < 0.0001). Patients with negative cyclin D1 expression had longer duration of deafness (p = 0.02) and higher 2,000-Hz hearing thresholds (p = 0.04) than cyclin D1+ patients. CONCLUSION: Cyclin D1 expression, present in nearly half of the cases, may play a role in the development of these tumors. Further studies are needed to fully understand the contributions of histopathologic and immunohistochemical factors to vestibular schwannoma biological activity.


Assuntos
Neoplasias dos Nervos Cranianos/genética , Neoplasias dos Nervos Cranianos/patologia , Regulação Neoplásica da Expressão Gênica/genética , Genes bcl-1/genética , Neuroma Acústico/genética , Neuroma Acústico/patologia , Doenças do Nervo Vestibulococlear/genética , Doenças do Nervo Vestibulococlear/patologia , Adolescente , Adulto , Idoso , Audiometria , Surdez/etiologia , Feminino , Perda Auditiva/etiologia , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Inclusão em Parafina , Núcleos Vestibulares/patologia
15.
Mol Biochem Parasitol ; 147(2): 211-23, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16564583

RESUMO

African trypanosomes (Trypanosoma brucei) have a digenetic lifecycle that alternates between the mammalian bloodstream and the tsetse fly vector. In the bloodstream, replicating long slender parasites transform into non-dividing short stumpy forms. Upon transmission into the fly midgut, short stumpy cells differentiate into actively dividing procyclics. A hallmark of this process is the replacement of the bloodstream-stage surface coat composed of variant surface glycoprotein (VSG) with a new coat composed of procyclin. Pre-existing VSG is shed by a zinc metalloprotease activity (MSP-B) and glycosylphosphatidylinositol-specific phospholipase C (GPI-PLC). We now provide a detailed analysis of the coordinate and inverse regulation of these activities during synchronous differentiation. MSP-B mRNA and protein levels are upregulated during differentiation at the same time as proteolysis whereas GPI-PLC levels decrease. When transcription or translation is inhibited, VSG release is incomplete and a substantial amount of protein stays cell-associated. Both modes of release are still evident under these conditions, but GPI hydrolysis plays a quantitatively minor role during normal differentiation. Nevertheless, GPI biosynthesis shifts early in differentiation from a GPI-PLC sensitive structure to a resistant procyclic-type anchor. Translation inhibition also results in a marked increase in the mRNA levels of both MSP-B and GPI-PLC, consistent with negative regulation by labile protein factors. The relegation of short stumpy surface GPI-PLC to a secondary role in differentiation suggests that it may play a more important role as a virulence factor within the mammalian host.


Assuntos
Regulação da Expressão Gênica , Glicoproteínas de Membrana/metabolismo , Metaloproteases/metabolismo , Proteínas de Protozoários/metabolismo , Trypanosoma brucei brucei/crescimento & desenvolvimento , Glicoproteínas Variantes de Superfície de Trypanosoma/metabolismo , Animais , Glicosilfosfatidilinositol Diacilglicerol-Liase , Estágios do Ciclo de Vida , Glicoproteínas de Membrana/genética , Metaloproteases/genética , Camundongos , Fosfatidilinositol Diacilglicerol-Liase , Proteínas de Protozoários/genética , Trypanosoma brucei brucei/citologia , Trypanosoma brucei brucei/genética , Trypanosoma brucei brucei/metabolismo , Glicoproteínas Variantes de Superfície de Trypanosoma/genética
16.
Otol Neurotol ; 27(8): 1180-5, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16983315

RESUMO

HYPOTHESIS: The purpose of this study was to examine the DNA methylation profile of several genes in a series of vestibular schwannomas, and to analyze its relationship with clinical and radiological features. BACKGROUND: Aberrant methylation of promoter regions is a major mechanism for silencing of tumor suppressor genes in several tumors. There is limited information about methylation status in vestibular schwannoma, with no clinical or radiological implications described to date. METHODS: The methylation status of 16 tumor-related genes including RASSF1A, RAR-B, VHL, PTEN, HMLH1, RB1, TP16, CASP8, ER, TIMP3, MGMT, DAPK, TP73, GSTP1, TP14, and THBS1 was examined in a series of 22 vestibular schwannomas.The bisulfite modification of genomic DNA was performed. Clinical and radiological features were compared with the methylation results. RESULTS: Methylation values from 9% to 27% were found in 12 of 16 genes tested, including RASSF1A, VHL, PTEN, TP16, CASP8, TIMP3, MGMT, DAPK, THBS1, HMLH1, TP73, and GSTP1. A significant association was found between CASP8 and RASSF1A methylation. Methylation of CASP8 was associated with the patient's age and the tumor size. Methylation of TP73 was associated with hearing loss. RASSF1A methylation was inversely correlated with the clinical growth index. CONCLUSION: Aberrant methylation of tumor-related genes may play a role in the development of vestibular schwannomas. Our results may provide useful clues to the development of prognostic assays for these tumors.


Assuntos
Metilação de DNA , Neuroma Acústico/genética , Adolescente , Adulto , Idoso , Limiar Auditivo/fisiologia , Feminino , Genes Supressores de Tumor/fisiologia , Perda Auditiva/genética , Humanos , Masculino , Pessoa de Meia-Idade , Neuroma Acústico/diagnóstico por imagem , Neuroma Acústico/fisiopatologia , Regiões Promotoras Genéticas/genética , Radiografia
17.
Ann Otol Rhinol Laryngol ; 115(9): 694-8, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17044542

RESUMO

OBJECTIVES: This study was performed to evaluate the impact of facial dysfunction on quality of life in patients who underwent surgery for vestibular schwannoma. Other factors with a possible impact on quality of life were also assessed. METHODS: We performed a retrospective review of 95 patients who underwent removal of a unilateral vestibular schwannoma. The Glasgow Benefit Inventory, an open-ended questionnaire, and a pain scale were sent to each patient. The questions were answered by 70 respondents (74%). After a minimum 1-year follow-up, the overall House-Brackmann postoperative facial function was grade I-II in 61% of patients, grade III-IV in 36%, and grade V-VI in 3%. RESULTS: The open-ended questionnaire showed that 33% of patients stated a complaint related to facial dysfunction; it was the main complaint for 13% of patients. No significant difference was found in terms of Glasgow Benefit Inventory scores between patients with and without facial dysfunction, nor between those with different House-Brackmann grades. The most frequent complaint after surgery was hearing loss (46%). Postoperative pain was significantly associated with a worse postoperative quality of life. CONCLUSIONS: An overestimation of the effect of facial paralysis after vestibular schwannoma resection may exist on the surgeon's part. Detailed information about the possibility of hearing loss, vestibular problems, and pain must be given to all patients.


Assuntos
Paralisia Facial/psicologia , Neuroma Acústico/cirurgia , Qualidade de Vida , Adulto , Idoso , Paralisia Facial/etiologia , Feminino , Perda Auditiva/etiologia , Perda Auditiva/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Neuroma Acústico/complicações , Neuroma Acústico/psicologia , Medição da Dor , Dor Pós-Operatória/psicologia , Estudos Retrospectivos , Inquéritos e Questionários
18.
Int J Parasitol ; 34(3): 411-21, 2004 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-15003500

RESUMO

Toxoplasma gondii rapidly elicits strong Type 1 cytokine-based immunity. The necessity for this response is well illustrated by the example of IFN-gamma and IL-12 gene knockout mice that rapidly succumb to the effects of acute infection. The parasite itself is skilled at sparking complex interactions in the innate immune system that lead to protective immunity. Neutrophils are one of the first cell types to arrive at the site of infection, and the cells release several proinflammatory cytokines and chemokines in response to Toxoplasma. Dendritic cells are an important source of IL-12 during infection with T. gondii and other microbial pathogens, and they are also specialized for high-level antigen presentation to T lymphocytes. Tachyzoites express at least two types of molecules that trigger innate immune cell cytokine production. One of these involves Toll-like receptor/MyD88 pathways common to many microbial pathogens. The second pathway is less conventional and involves molecular mimicry between a parasite cyclophilin and host CC chemokine receptor 5-binding ligands. Neutrophils, dendritic cells and Toxoplasma work together to elicit the immune response required for host survival. Cytokine and chemokine cross-talk between parasite-triggered neutrophils and dendritic cells results in recruitment, maturation and activation of the latter. Neutrophil-empowered dendritic cells possess properties expected of highly potent antigen presenting cells that drive T helper 1 generation.


Assuntos
Células Dendríticas/imunologia , Neutrófilos/imunologia , Toxoplasma/imunologia , Toxoplasmose/imunologia , Animais , Comunicação Celular/imunologia , Humanos , Imunidade Celular , Camundongos
19.
J Hazard Mater ; 246-247: 126-34, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23291337

RESUMO

The aim of this study was to assess the activity of catalysts formed by nanostructured zinc oxide supported on stainless steel wire mesh for the photocatalytic degradation of methylene blue under UV irradiation. Catalysts prepared by means of different low temperature synthesis methods, as described in a previous work (Vu et al., Mater. Res. Bull. 47 (2012) 1577-1586) were tested. A new activity parameter was introduced in order to compare the catalytic activity of the different catalysts. The best catalyst showed a catalytic activity higher than that of the reference material TiO(2) P25 (Degussa-Evonik). This high activity is attributed to a higher quantum yield derived from the small particle length of the ZnO deposited on the wire mesh. The photocatalytic degradation kinetics of methylene blue fitted a potential model with n orders ranging from 0.5 to 6.9. Reaction orders over 1 were attributed to catalyst deactivation during the reaction resulting from the photocorrosion of ZnO.


Assuntos
Azul de Metileno/efeitos da radiação , Fotólise , Poluentes Químicos da Água/efeitos da radiação , Óxido de Zinco/química , Azul de Metileno/química , Nanopartículas/química , Aço Inoxidável , Raios Ultravioleta , Poluentes Químicos da Água/química
20.
Otol Neurotol ; 32(1): 136-40, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21131888

RESUMO

HYPOTHESIS: The proto-oncogen cyclin D1 has been implicated in the development and behavior of vestibular schwannoma. This study evaluates the association between cyclin D1 expression and other known prognostic factors in facial function outcome 1 year after vestibular schwannoma surgery. METHODS: Sixty-four patients undergoing surgery for vestibular schwannoma were studied. Immunohistochemistry analysis was performed with anticyclin D1 in all cases. Cyclin D1 expression, as well as other demographic, clinical, radiologic, and intraoperative data, was correlated with 1-year postoperative facial function. RESULTS: Good 1-year facial function (Grades 1-2) was achieved in 73% of cases. Cyclin D1 expression was found in 67% of the tumors. Positive cyclin D1 staining was more frequent in patients with Grades 1 to 2 (75%) than in those with Grades 3 to 6 (25%). Other significant variables were tumor volume and facial nerve stimulation after tumor resection. The area under the receiver operating characteristics curve increased when adding cyclin D1 expression to the multivariate model. CONCLUSION: Cyclin D1 expression is associated to facial outcome after vestibular schwannoma surgery. The prognostic value of cyclin D1 expression is independent of tumor size and facial nerve stimulation at the end of surgery.


Assuntos
Ciclina D1/metabolismo , Face/fisiopatologia , Nervo Facial/fisiopatologia , Neuroma Acústico/cirurgia , Adolescente , Adulto , Idoso , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neuroma Acústico/metabolismo , Neuroma Acústico/fisiopatologia , Período Pós-Operatório , Curva ROC , Resultado do Tratamento
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