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1.
Vaccine ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38981741

RESUMO

OBJECTIVES: To measure and evaluate the impact of receiving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines in pregnancy on immunoglobulin G (IgG) and immunoglobulin A (IgA) titres in maternal and infant samples. DESIGN: Prospective cohort study. SETTING: Tertiary obstetric centre. POPULATION OR SAMPLE: 52 pregnant women who received one or more SARS-CoV-2 vaccine doses during pregnancy and their neonates. METHODS: IgG and IgA concentrations against SARS-CoV-2 antigens were measured from samples collected at delivery and 4-6 weeks postpartum and compared using Spearman correlations. MAIN OUTCOME MEASURES: Maternal and infant IgG and IgA titres in response to vaccination and infection in pregnancy. RESULTS: In maternal serum collected at delivery, participants without evidence of prior infection who received 3 + doses of a SARS-CoV-2 vaccine had higher Anti-Spike (S) IgG geometric mean concentrations (log10 AU/mL)(GMC) than those who received 2 doses (3 + Doses = 5.00, 2 Doses = 4.60, p = 0.08). The differences in IgG Anti-S GMC were statistically significant in cord serum, and in postpartum samples of maternal serum, infant serum and breast milk (Cord GMCs: 3 + Doses = 5.32, 2 Doses = 4.98, p < 0.05; Postpartum maternal serum GMCs: 3 + Doses = 5.25, 2 Doses = 4.57, p < 0.001; Postpartum infant serum GMCs: 3 + Doses = 5.10, 2 Doses = 4.72, p = 0.03; Postpartum breast milk GMCs: 3 + Doses = 2.61, 2 Doses = 1.94, p < 0.0001). Among participants with 3 + Doses, those with evidence of SARS-CoV-2 infection had statistically significant higher anti-S IgG GMCs than those without prior infection (Maternal serum at delivery: SARS-CoV-2+=5.65, SARS-CoV-2-=5.00, p = 0.004; Cord: SARS-CoV-2+=5.68, SARS-CoV-2-=5.32, p = 0.02; Postpartum maternal serum: SARS-CoV-2+=5.66, SARS-CoV-2-=5.25, p < 0.001; postpartum infant serum: SARS-CoV-2+=5.50, SARS-CoV-2-=5.10, p = 0.003; Postpartum breast milk: SARS-COV-2+=3.25, SARS-COV-2-=2.61, p = 0.009). Significant positive correlations were found for anti-S IgG titres between paired maternal and infant samples at delivery and postpartum (Delivery: R = 0.91, p < 0.001; postpartum: R = 0.86, p < 0.001). CONCLUSIONS: Receipt of a SARS-CoV-2 vaccine and SARS-CoV-2 infection elicit strong IgG and IgA antibody responses in pregnant women with evidence of transplacental transfer to the fetus.

2.
Vaccine ; 41(48): 7183-7191, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37865598

RESUMO

OBJECTIVE: To describe self-reported reactogenicity, pregnancy outcomes, and SARS-CoV-2 infection following COVID-19 vaccination during pregnancy. DESIGN: National, prospective cohort study. SETTING: Participants across Canada were enrolled from July 2021 until June 2022. POPULATION: Individuals pregnant during the COVID-19 pandemic, regardless of vaccination status, were included. METHODS: The Canadian COVID-19 Vaccine Registry for Pregnant and Lactating Individuals (COVERED) was advertised through traditional and social media. Surveys were administered at baseline, following each vaccine dose if vaccinated, pregnancy conclusion, and every two months for 14 months. Changes to pregnancy or vaccination status, SARS-CoV-2 infections, or significant health events were recorded. MAIN OUTCOME MEASURES: Reactogenicity (local and systemic adverse events, and serious adverse events) within 1 week post-vaccination, pregnancy and neonatal outcomes, and subsequent SARS-CoV-2 infection. RESULTS: Among 2868 participants who received 1-2 doses of a COVID-19 vaccine during pregnancy, adverse events described included: headache (19.5-33.9%), nausea (4.8-13.8%), fever (2.7-10.2%), and myalgia (33.4-42.2%). Reactogenicity was highest after the 2nd dose of vaccine in pregnancy. Compared to 1660 unvaccinated participants, there were no statistically significant differences in adverse pregnancy or infant outcomes, aside from an increased risk of NICU admission ≥ 24 h among the unvaccinated group. During follow-up, there was a higher rate of participant-reported SARS-CoV-2 infection in the unvaccinated compared to the vaccinated group (18[47.4%] vs. 786[27.3%]). CONCLUSIONS: Participant-reported reactogenicity was similar to reports from non-pregnant adults. There was no increase in adverse pregnancy and birth outcomes among vaccinated vs. unvaccinated participants and lower rates of SARS-CoV-2 infection were reported in vaccinated participants. TWEETABLE ABSTRACT: No significant increase in adverse pregnancy or infant outcomes among vaccinated versus unvaccinated pregnant women in Canada.


Assuntos
COVID-19 , Adulto , Feminino , Humanos , Recém-Nascido , Gravidez , Canadá/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Lactação , Pandemias , Resultado da Gravidez , Estudos Prospectivos , SARS-CoV-2 , Vacinação/efeitos adversos
3.
Arch Biochem Biophys ; 731: 109424, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36220378

RESUMO

As in most enveloped RNA viruses, the Respiratory Syncytial Virus Matrix (RSV-M) protein plays key roles in viral assembly and uncoating. It also plays non-structural roles related to transcription modulation through nucleo-cytoplasmic shuttling and nucleic acid binding ability. We dissected the structural and conformational changes underlying the switch between multiple functionalities, identifying Ca2+ binding as a key factor. To this end, we tackled the analysis of M's conformational stability and equilibria. While in silico calculations predict two potential calcium binding sites per protomer, purified RSV-M dimer contains only one strongly bound calcium ion per protomer. Incubation of RSV-M in the presence of excess Ca2+ leads to an increase in the thermal stability, confirming additional Ca2+ binding sites. Moreover, mild denaturant concentrations trigger the formation of higher order oligomers which are otherwise prevented under Ca2+ saturation conditions, in line with the stabilizing effect of the additional low affinity binding site. On the other hand, Ca2+ removal by chelation at pH 7.0 causes a substantial decrease in the thermal stability leading to the formation of amorphous, spherical-like aggregates, as assessed by TEM. Even though the Ca2+ content modulates RSV-M oligomerization propensity, it does affect its weak RNA binding ability. RSV-M undergoes a substantial conformational change at pHs 4.0 to 5.0 that results in the exposure of hydrophobic surfaces, an increase beta sheet content but burial of tryptophan residues. While low ionic strength promotes dimer dissociation at pH 4.0, physiological concentrations of NaCl lead to the formation of soluble oligomers smaller than 400 kDa at pH 4.0 or insoluble aggregates with tubular morphology at pH 5.0, supporting a fine tuning by pH. Furthermore, the dissociation constants estimated for the low- and high affinity calcium binding sites are 13 µM and 58 nM, respectively, suggesting an intracellular calcium sensing mechanism of RSV-M upon infection. We uncover a finely tuned interplay between calcium binding, ionic strength, and pH changes compatible with the different cellular compartments where M plays key roles, revealing diverse conformational equilibria, oligomerization, and high order structures, required to stabilize the virion particle by a layer of molecules positioned between the membrane and the nucleocapsid.


Assuntos
Cálcio , Vírus Sincicial Respiratório Humano , Subunidades Proteicas , Vírus Sincicial Respiratório Humano/química , Montagem de Vírus , Concentração Osmolar , Ligação Proteica
4.
Arch Biochem Biophys ; 671: 77-86, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31229488

RESUMO

Virus from the Mononegavirales order share common features ranging from virion structure arrangement to mechanisms of replication and transcription. One of them is the way the nucleoprotein (N) wraps and protects the RNA genome from degradation by forming a highly ordered helical nucleocapsid. However, crystal structures from numerous Mononegavirales reveal that binding to the nucleoprotein results in occluded nucleotides that hinder base pairing necessary for transcription and replication. This hints at the existence of alternative conformations of the N protein that would impact on the protein-RNA interface, allowing for transient exposure of the nucleotides without complete RNA release. Moreover, the regulation between the alternative conformations should be finely tuned. Recombinant expression of N from the respiratory syncytial virus form regular N/RNA common among all Mononegavirales, and these constitute an ideal minimal unit for investigating the mechanisms through which these structures protect RNA so efficiently while allowing for partial accessibility during transcription and replication. Neither pH nor high ionic strength could dissociate the RNA but led to irreversible aggregation of the nucleoprotein. Low concentrations of guanidine chloride dissociated the RNA moiety but leading to irreversible aggregation of the protein moiety. On the other hand, high concentrations of urea and long incubation periods were required to remove bound RNA. Both denaturants eventually led to unfolding but converged in the formation of an RNA-free ß-enriched intermediate species that remained decameric even at high denaturant concentrations. Although the N-RNA rings interact with the phosphoprotein P, the scaffold of the RNA polymerase complex, this interaction did not lead to RNA dissociation from the rings in vitro. Thus, we have uncovered complex equilibria involving changes in secondary structure of N and RNA loosening, processes that must take place in the context of RNA transcription and replication, whose detailed mechanisms and cellular and viral participants need to be established.


Assuntos
Proteínas do Nucleocapsídeo/metabolismo , RNA Viral/metabolismo , Concentração de Íons de Hidrogênio , Simulação de Dinâmica Molecular , Conformação de Ácido Nucleico , Proteínas do Nucleocapsídeo/química , Concentração Osmolar , Ligação Proteica , Estrutura Secundária de Proteína , Estabilidade de RNA , RNA Viral/química , Vírus Sincicial Respiratório Humano/química , Temperatura , Termodinâmica
5.
Plant Cell Rep ; 36(10): 1547-1559, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28667403

RESUMO

KEY MESSAGE: A large, 53-kbp, intact DNA fragment was inserted into the wheat ( Triticum aestivum L.) genome. FISH analyses of individual transgenic events revealed multiple insertions of intact fragments. Transferring large intact DNA fragments containing clusters of resistance genes or complete metabolic pathways into the wheat genome remains a challenge. In a previous work, we showed that the use of dephosphorylated cassettes for wheat transformation enabled the production of simple integration patterns. Here, we used the same technology to produce a cassette containing a 44-kb Arabidopsis thaliana BAC, flanked by one selection gene and one reporter gene. This 53-kb linear cassette was integrated in the bread wheat (Triticum aestivum L.) genome by biolistic transformation. Our results showed that transgenic plants harboring the entire cassette were generated. The inheritability of the cassette was demonstrated in the T1 and T2 generation. Surprisingly, FISH analysis performed on T1 progeny of independent events identified double genomic insertions of intact fragments in non-homoeologous positions. Inheritability of these double insertions was demonstrated by FISH analysis of the T1 generation. Relative conclusions that can be drawn from molecular or FISH analysis are discussed along with future prospects of the engineering of large fragments for wheat transformation or genome editing.


Assuntos
Biolística/métodos , DNA de Plantas/genética , Genoma de Planta/genética , Hibridização in Situ Fluorescente/métodos , Mutagênese Insercional/métodos , Triticum/genética , Arabidopsis/genética , Plantas Geneticamente Modificadas
7.
Opt Express ; 24(18): 20335-45, 2016 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-27607640

RESUMO

An iterative alternate projection-based algorithm is developed to design structured surface reflectors to operate as beam splitters at GHz and THz frequencies. To validate the method, a surface profile is determined to achieve a reflector at 610 GHz that generates four equal-intensity beams towards desired directions of ±12.6° with respect to the specular reflection axis. A prototype is fabricated and the beam splitter behavior is experimentally demonstrated. Measurements confirm a good agreement (within 1%) with computer simulations using Feko, validating the method. The beam splitter at 610 GHz has a measured efficiency of 78% under oblique incidence illumination that ensures a similar intensity between the four reflected beams (variation of about 1%).

8.
Biotech Histochem ; 90(8): 573-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26052817

RESUMO

Continuous production of the E7 protein from different types of high risk human papilloma virus (HPV) is required for progression of malignancy. We developed antibodies against HPV type 16 E7 and E2 proteins to evaluate their utility as markers for diagnosis during early stages of cervical cancer. Forty biopsies from uterine cervices were diagnosed as low grade intraepithelial lesion (LSIL), high grade intraepithelial lesion (HSIL), squamous carcinoma (SC), in situ adenocarcinoma (ISA) and invasive adenocarcinoma (AC), all of which were infected with HPV 16. Immunohistochemistry was used to investigate the expressions of E7 and E2 (both from HPV 16) and p16. P16 was expressed in eight of 12 LSILs, in all HSILs, in 16 of 18 SC and in all ACs. E2 was expressed in six of 12 LSILs. E7 was positive in eight of 12 LSILs and in all HSIL and carcinomas. The expressions of E2 and E7 of HPV16 related to p16 expression confirmed the value of the viral oncogenic proteins as complementary to histology and support the carcinogenic model of the uterine cervix, because HPVDNA integration into cellular DNA implies the destruction of the gene encoding E2, which suppresses the expression of the E6 and E7 oncoproteins. E2 from HPV16 could be marker for LSILs, while E7 could be a marker for progression of LSILs to HSILs in patients infected by HPV16, because viral typing has little positive predictive value.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Detecção Precoce de Câncer/métodos , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Lesões Pré-Cancerosas/metabolismo , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/metabolismo , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Proteínas de Neoplasias/metabolismo , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/patologia
9.
Diabetes Metab ; 41(4): 291-300, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25575429

RESUMO

AIM: The study investigated the relationship of general (body mass index [BMI]) and central (waist circumference [WC]; waist-hip ratio [WHipR]; waist-height ratio [WHeightR]) adiposity with all-cause and cardiovascular disease (CVD)-related mortality in an Asian population with diabetes. METHODS: A total of 13,278 participants with type 2 diabetes mellitus (T2DM) recruited from public-sector primary-care and specialist outpatients clinics in Singapore were followed-up for a median duration of 2.9 years, during which time there were 524 deaths. Cox proportional-hazards regression and competing-risk models were used to obtain hazard ratios (HRs) for anthropometric variables of all-cause and CVD-related mortality. RESULTS: After adjusting for BMI, the highest quintiles of WC, WHipR and WHeightR were all positively associated with mortality compared with the lowest quintiles, with WHeightR exhibiting the largest effect sizes [all-cause mortality HR: 2.13, 95% confidence interval (CI): 1.33-3.42; CVD-related mortality HR: 3.42, 95% CI: 1.62-7.19]. Being overweight but not obese (BMI:≥23.0 but<27.5kg/m(2)) was associated with a decreased risk of CVD-related mortality in those aged≥65 years (HR: 0.47, 95% CI: 0.29-0.75), but not in those aged<65 years (HR: 1.11, 95% CI: 0.49-2.50). CONCLUSION: Overweight, but not obesity, was associated with a reduction in risk of mortality. This was seen in T2DM patients aged≥65 years, but not in those younger than this. At the same BMI, having higher central-obesity indices such as WC, WHipR and WHeightR also increased the risk of mortality.


Assuntos
Pesos e Medidas Corporais , Doenças Cardiovasculares/mortalidade , Diabetes Mellitus Tipo 2/mortalidade , Obesidade/mortalidade , Adiposidade/etnologia , Idoso , Povo Asiático/estatística & dados numéricos , Índice de Massa Corporal , Pesos e Medidas Corporais/normas , Pesos e Medidas Corporais/estatística & dados numéricos , Doenças Cardiovasculares/complicações , Causas de Morte , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Indicadores Básicos de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/etnologia , Obesidade/metabolismo , Fatores de Risco , Singapura/epidemiologia , Circunferência da Cintura/etnologia , Relação Cintura-Quadril/estatística & dados numéricos
10.
Internist (Berl) ; 54(3): 287-301, 2013 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-23455659

RESUMO

Endoscopic submucosal dissection (ESD) was developed in Japan but has now also become permanently established in various centers in Europe. ESD is an endoscopic en bloc mucosal resection technique for the treatment of early cancers with a diameter >1 cm and also superficial precancerous lesions, which could only be removed unsatisfactorily in several fragments or with uncertain lateral safety margins using previous loop excision procedures. Using ESD a lesion is excised after circular marking and generous submucosal injection with a safety margin of approximately 5 mm and subsequently resected at the level of the submucosa with a 1-3 mm short diathermic knife. ESD requires high technical skills in interventional endoscopy and is more time-consuming than snare resection techniques. However, numerous studies have shown a clear superiority for ESD with respect to the R0 resection rate and the local recurrence rate. The present article gives a current review of the use of ESD in the upper and lower gastrointestinal tract and demonstrates perspectives of the procedure.


Assuntos
Dissecação/métodos , Endoscopia Gastrointestinal/métodos , Neoplasias Gastrointestinais/patologia , Neoplasias Gastrointestinais/cirurgia , Mucosa/patologia , Mucosa/cirurgia , Dissecação/tendências , Endoscopia Gastrointestinal/tendências , Humanos
11.
Endoscopy ; 44(5): 527-36, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22389230

RESUMO

PillCam colon capsule endoscopy (CCE) is an innovative noninvasive, and painless ingestible capsule technique that allows exploration of the colon without the need for sedation and gas insufflation. Although it is already available in European and other countries, the clinical indications for CCE as well as the reporting and work-up of detected findings have not yet been standardized. The aim of this evidence-based and consensus-based guideline, commissioned by the European Society of Gastrointestinal Endoscopy (ESGE) is to furnish healthcare providers with a comprehensive framework for potential implementation of this technique in a clinical setting.


Assuntos
Endoscopia por Cápsula/normas , Endoscopia por Cápsula/métodos , Catárticos/administração & dosagem , Neoplasias do Colo/diagnóstico , Pólipos do Colo/diagnóstico , Contraindicações , Enema , Humanos , Doenças Inflamatórias Intestinais/diagnóstico , Prontuários Médicos/normas , Educação de Pacientes como Assunto
12.
Endoscopy ; 43(6): 533-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21425038

RESUMO

This review reports the highlights of the first International Conference on Capsule and Double-Balloon Endoscopy, held in Paris (27 - 28 August 2010), under the chairmanship of Professor G. Gay (Nancy, France). The conference was devoted to the technical issues and clinical experience related to capsule endoscopy and double-balloon endoscopy (DBE), techniques that have been developed over the past decade for the endoscopic investigation of intestinal diseases. The conference focused on the technical advances of new-generation endoscopes and capsules and the clinical experience gained with capsule endoscopy and DBE. Important advances in the knowledge of obscure gastrointestinal bleeding, inflammatory bowel diseases, and celiac disease were also discussed. The second part of the conference was mainly devoted to the investigation of the colon and discussed the technical issues and results of initial controlled studies of the colonic capsule vs. conventional colonoscopy. In addition, the clinical usefulness of double colonoscopy was demonstrated in patients with previously failed colonoscopy. Finally, the role of DBE was discussed with respect to the investigation and treatment of patients with surgically modified anatomy. The conference was attended by 750 delegates and presented a unique opportunity for an in-depth review of the current knowledge in the field and to ascertain/determine the main lines for the future developments of capsule endoscopy and DBE.


Assuntos
Endoscopia por Cápsula , Enteroscopia de Duplo Balão , Gastroenteropatias/diagnóstico , Colonoscopia , Humanos
13.
Nanotechnology ; 21(43): 435301, 2010 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-20876979

RESUMO

A generic, CMOS compatible strategy for transferring a block copolymer template to a semiconductor substrate is demonstrated. An aluminum oxide (Al(2)O(3)) hard mask is selectively deposited by atomic layer deposition in an organized array of holes obtained in a PS matrix via PS-b-PMMA self-assembly. The Al(2)O(3) nanodots act as a highly resistant mask to plasma etching, and are used to pattern high aspect ratio (>10) silicon nanowires and nanopillars.

14.
J Dairy Sci ; 92(9): 4444-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19700705

RESUMO

Low sensitivity of a single bulk tank milk culture is a major limitation for detection of mycoplasma organisms. We hypothesized that sedimentation of Mycoplasma spp. in a milk sample by centrifugation followed by resuspension in a small volume of fluid before agar plating would increase the ability to detect Mycoplasma spp. compared with direct conventional culture. The experiment was conducted to determine recovery of Mycoplasma spp. from milk as affected by 1) treatment (centrifugation vs. conventional method); 2) 2 species (Mycoplasma bovis and Mycoplasma californicum and 4 strains for each species); and 3) 4 different concentrations of Mycoplasma spp. (1,000, 100, 10, and 1 cfu/mL). A 5-mL portion of mycoplasma suspension from each strain was inoculated into 45 mL of fresh bulk tank milk to achieve concentrations of 1,000, 100, 10, and 1 cfu/mL. Treatment samples were vigorously mixed and centrifuged at 5,000 x g for 30 min. Control samples were vigorously mixed. All samples were plated on modified Hayflick agar. Plates were incubated at 37 degrees C and 5% CO(2) for 5 d. Mean (+/-SE) log(10) mycoplasma counts (cfu/mL) in the treatment groups (1.91 +/- 0.15) were higher than those in the control groups (1.70 +/- 0.16). Recovery of at least 1 mycoplasma colony on agar culture was 100% in both treatment and control groups at high, medium, and low concentrations. At the lowest concentration, recovery of at least 1 mycoplasma colony on agar culture in treatment and control groups was 75% (n = 12/16) and 18.75% (n = 3/16), respectively. Centrifugation of milk followed by suspension in a smaller volume of saline before conventional culture increased the ability to detect mycoplasma microorganisms in the milk sample compared with controls. Recovery by centrifugation appeared best at the lowest concentration where detection of a positive sample was 4 times more likely than when conventional methods were used.


Assuntos
Microbiologia de Alimentos , Tecnologia de Alimentos/métodos , Leite/microbiologia , Mycoplasma/isolamento & purificação , Animais , Centrifugação , Contagem de Colônia Microbiana
15.
Appl Environ Microbiol ; 75(8): 2266-74, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19233951

RESUMO

Metallothioneins (MTs) are small cysteine-rich peptides involved in metal homeostasis and detoxification. We have characterized two MT genes, HcMT1 and HcMT2, from the ectomycorrhizal fungus Hebeloma cylindrosporum in this study. Expression of HcMT1 and HcMT2 in H. cylindrosporum under metal stress conditions was studied by competitive reverse transcription-PCR analysis. The full-length cDNAs were used to perform functional complementation in mutant strains of Saccharomyces cerevisiae. As revealed by heterologous complementation assays in yeast, HcMT1 and HcMT2 each encode a functional polypeptide capable of conferring increased tolerance against Cd and Cu, respectively. The expression levels of HcMT1 were observed to be at their maximum at 24 h, and they increased as a function of Cu concentration. HcMT2 was also induced by Cu, but the expression levels were lower than those for HcMT1. The mRNA accumulation of HcMT1 was not influenced by Cd, whereas Cd induced the transcription of HcMT2. Zn, Pb, and Ni did not affect the transcription of HcMT1 or of HcMT2. Southern blot analysis revealed that both of these genes are present as a single copy in H. cylindrosporum. While the promoters of both HcMT1 and HcMT2 contained the standard stress response elements implicated in the metal response, the numbers and varieties of potential regulatory elements were different in these promoters. These results show that ectomycorrhizal fungi encode different MTs and that each of them has a particular pattern of expression, suggesting that they play critical specific roles in improving the survival and growth of ectomycorrhizal trees in ecosystems contaminated by heavy metals.


Assuntos
Regulação Fúngica da Expressão Gênica , Hebeloma/fisiologia , Metalotioneína/biossíntese , Metais/toxicidade , Sequência de Aminoácidos , DNA Fúngico/química , DNA Fúngico/genética , Deleção de Genes , Perfilação da Expressão Gênica , Teste de Complementação Genética , Hebeloma/metabolismo , Metalotioneína/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA
17.
Nature ; 452(7183): 88-92, 2008 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-18322534

RESUMO

Mycorrhizal symbioses--the union of roots and soil fungi--are universal in terrestrial ecosystems and may have been fundamental to land colonization by plants. Boreal, temperate and montane forests all depend on ectomycorrhizae. Identification of the primary factors that regulate symbiotic development and metabolic activity will therefore open the door to understanding the role of ectomycorrhizae in plant development and physiology, allowing the full ecological significance of this symbiosis to be explored. Here we report the genome sequence of the ectomycorrhizal basidiomycete Laccaria bicolor (Fig. 1) and highlight gene sets involved in rhizosphere colonization and symbiosis. This 65-megabase genome assembly contains approximately 20,000 predicted protein-encoding genes and a very large number of transposons and repeated sequences. We detected unexpected genomic features, most notably a battery of effector-type small secreted proteins (SSPs) with unknown function, several of which are only expressed in symbiotic tissues. The most highly expressed SSP accumulates in the proliferating hyphae colonizing the host root. The ectomycorrhizae-specific SSPs probably have a decisive role in the establishment of the symbiosis. The unexpected observation that the genome of L. bicolor lacks carbohydrate-active enzymes involved in degradation of plant cell walls, but maintains the ability to degrade non-plant cell wall polysaccharides, reveals the dual saprotrophic and biotrophic lifestyle of the mycorrhizal fungus that enables it to grow within both soil and living plant roots. The predicted gene inventory of the L. bicolor genome, therefore, points to previously unknown mechanisms of symbiosis operating in biotrophic mycorrhizal fungi. The availability of this genome provides an unparalleled opportunity to develop a deeper understanding of the processes by which symbionts interact with plants within their ecosystem to perform vital functions in the carbon and nitrogen cycles that are fundamental to sustainable plant productivity.


Assuntos
Basidiomycota/genética , Basidiomycota/fisiologia , Genoma Fúngico/genética , Micorrizas/genética , Micorrizas/fisiologia , Raízes de Plantas/microbiologia , Simbiose/fisiologia , Abies/microbiologia , Abies/fisiologia , Basidiomycota/enzimologia , Proteínas Fúngicas/classificação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação da Expressão Gênica , Genes Fúngicos/genética , Hifas/genética , Hifas/metabolismo , Micorrizas/enzimologia , Raízes de Plantas/fisiologia , Simbiose/genética
20.
Endoscopy ; 40(1): 16-22, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18058656

RESUMO

BACKGROUND AND STUDY AIMS: The study aim was to compare the diagnostic yield of capsule endoscopy and esophagogastroduodenoscopy (EGD) in patients with suspected esophageal disease. Secondary aims were to assess interobserver variability of capsule endoscopy readings and safety. PATIENTS AND METHODS: In total, 98 patients (53 men, 53 +/- 13 years) with an indication for EGD were included. The patient population was artificially enriched to include two thirds of patients with abnormal esophageal findings at EGD, which was followed by capsule endoscopy. Capsule recordings were blindly read by three endoscopists, one from the center that recruited the patient and two from the other center. Study outcomes were the findings described on EGD and capsule endoscopy, agreement between EGD and capsule endoscopy for findings, quality of the capsule recording, and interobserver agreement for capsule endoscopy quality and findings. RESULTS: EGD was normal in 34 patients and showed esophageal findings in 62 (esophagitis 28, hiatus hernia 21, varices 21, Barrett's esophagus 11, others 7). Average esophageal transit time of the capsule was 361 +/- 393 seconds. Capsule endoscopy was normal in 36 patients but detected esophagitis in 23, hiatus hernia in 0, varices in 23, Barrett's esophagus in 18, and others in 4. The positive predictive value of capsule endoscopy was 80.0 % and the negative predictive value was 61.1 %. Overall agreement per patient was moderate between EGD and capsule endoscopy for the per-patient (kappa = 0.42) and per-findings (kappa = 0.40) analyses. Interobserver agreement between capsule endoscopy readings was moderate for findings (kappa = 0.39) and quality assessment (kappa = 0.24). No adverse event was observed after either EGD or capsule endoscopy. CONCLUSION: In this study, despite artificial prevalence enrichment, capsule endoscopy showed a moderate sensitivity and specificity in the detection of esophageal diseases.


Assuntos
Endoscopia por Cápsula/métodos , Endoscopia Gastrointestinal/métodos , Doenças do Esôfago/diagnóstico , Esofagoscopia/métodos , Adulto , Idoso , Análise de Variância , Método Duplo-Cego , Duodenoscopia/métodos , Neoplasias Esofágicas/diagnóstico , Varizes Esofágicas e Gástricas/diagnóstico , Feminino , Refluxo Gastroesofágico/diagnóstico , Gastroscopia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Probabilidade , Medição de Risco , Sensibilidade e Especificidade
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