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2.
Arq Bras Cardiol ; 119(1): 48-56, 2022 07.
Article in English, Portuguese | MEDLINE | ID: mdl-35544849

ABSTRACT

BACKGROUND: Left atrial appendage (LAA) closure has been an alternative to oral anticoagulation (OAC) for stroke prevention in patients with non-valvular atrial fibrillation (NVAF). OBJECTIVES: To report the first results of an initial multicenter experience in Brazil and to investigate the feasibility, safety, and efficacy of LAA closure with the new LAmbre device. METHODS: We collected procedural and follow-up data of 51 consecutive patients with non-valvular atrial fibrillation, restrictions for long-term OAC and suitable anatomy that underwent LAA closure with the LAmbre device in 18 centers in Brazil. Procedural indications were significant bleeding under OAC (47.1%), stroke or persistent LAA thrombus despite OAC (27.5%), bleeding plus stroke (17.6%), other clinical contraindications for OAC (5.9%), and patient's choice due to sports practice (1.9%). RESULTS: Twenty-five men (49%) and 26 women (51%), with a mean age of 76±7.7 years, mean CHA2DS2-VASc score of 4.6± 1.7 and mean HAS-BLED score of 3.4± 1.1 were studied. Procedural success rate was 100%. Procedure-related immediate complications were pericardial effusion in two patients, and immediate device embolization in one case. No large residual shunts (> 5 mm) were observed, and small shunts (<5mm) were detected in four patients by color Doppler at the end of the procedure. After a mean follow-up of 18 ± 12 months, there were no deaths, strokes nor any other major complications. CONCLUSION: LAA occlusion with the LAmbre device was safe and effective in this small case series. Despite these encouraging initial results, the small number of cases warrants further studies with longer-term follow-up.


FUNDAMENTO: A oclusão do apêndice atrial esquerdo (AAE) tem se mostrado uma alternativa à terapia de anticoagulação oral (ACO) para prevenção de acidente vascular cerebral (AVC) em pacientes com fibrilação atrial não valvar (FANV). OBJETIVOS: Descrever os primeiros resultados de uma experiência inicial multicêntrica no Brasil e investigar a viabilidade, a segurança e a eficácia da oclusão do AAE com o novo dispositivo LAmbre. MÉTODOS: Coletamos dados do procedimento e do acompanhamento de 51 pacientes consecutivos com FANV, restrições para ACO em longo prazo e com anatomia adequada, submetidos à oclusão do AAE com o dispositivo LAmbre em 18 centros no Brasil. Indicações para o procedimento foram: sangramento importante em pacientes recebendo ACO (47,1%), AVC ou trombo persistente no AAE apesar de ACO adequada (27.5%), sangramento e AVC (17.6%), outras contraindicações clínicas apara ACO (5,9%), e escolha do paciente devido à prática esportiva (1,9%). RESULTADOS: Foram estudados 25 homens (49%) e 26 mulheres (51%), com idade média de 76±7,7 anos, escore CHA2DS2-VASc médio de 4,6± 1,7 e escore HAS-BLED médio de 3.4± 1,1. A taxa de sucesso do procedimento foi de 100%. As complicações imediatas relacionadas ao procedimento foram derrame pericárdico em dois pacientes, e embolização do dispositivo em um caso. Não foram observados shunts residuais > 5mm. Shunts < 5mm foram detectados em quatro pacientes por Doppler colorido ao final do procedimento. Após um período médio de acompanhamento de 18 meses ± 12 meses, não foram observados óbito, AVC ou complicações maiores. CONCLUSÃO: A oclusão do AAE com o dispositivo LAmbre foi segura e eficaz nesta pequena série de casos. Apesar desses resultados iniciais encorajadores, dado o pequeno número de casos, serão necessários mais estudos com um maior período de acompanhamento.


Subject(s)
Atrial Appendage , Atrial Fibrillation , Stroke , Aged , Aged, 80 and over , Atrial Appendage/diagnostic imaging , Atrial Appendage/surgery , Atrial Fibrillation/complications , Atrial Fibrillation/surgery , Brazil , Cardiac Catheterization/methods , Female , Humans , Male , Stroke/etiology , Stroke/prevention & control , Treatment Outcome
3.
Arq. bras. cardiol ; 119(1): 48-56, abr. 2022. tab, graf
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1383717

ABSTRACT

Resumo Fundamento A oclusão do apêndice atrial esquerdo (AAE) tem se mostrado uma alternativa à terapia de anticoagulação oral (ACO) para prevenção de acidente vascular cerebral (AVC) em pacientes com fibrilação atrial não valvar (FANV). Objetivos Descrever os primeiros resultados de uma experiência inicial multicêntrica no Brasil e investigar a viabilidade, a segurança e a eficácia da oclusão do AAE com o novo dispositivo LAmbre. Métodos Coletamos dados do procedimento e do acompanhamento de 51 pacientes consecutivos com FANV, restrições para ACO em longo prazo e com anatomia adequada, submetidos à oclusão do AAE com o dispositivo LAmbre em 18 centros no Brasil. Indicações para o procedimento foram: sangramento importante em pacientes recebendo ACO (47,1%), AVC ou trombo persistente no AAE apesar de ACO adequada (27.5%), sangramento e AVC (17.6%), outras contraindicações clínicas apara ACO (5,9%), e escolha do paciente devido à prática esportiva (1,9%). Resultados Foram estudados 25 homens (49%) e 26 mulheres (51%), com idade média de 76±7,7 anos, escore CHA2DS2-VASc médio de 4,6± 1,7 e escore HAS-BLED médio de 3.4± 1,1. A taxa de sucesso do procedimento foi de 100%. As complicações imediatas relacionadas ao procedimento foram derrame pericárdico em dois pacientes, e embolização do dispositivo em um caso. Não foram observados shunts residuais > 5mm. Shunts < 5mm foram detectados em quatro pacientes por Doppler colorido ao final do procedimento. Após um período médio de acompanhamento de 18 meses ± 12 meses, não foram observados óbito, AVC ou complicações maiores. Conclusão A oclusão do AAE com o dispositivo LAmbre foi segura e eficaz nesta pequena série de casos. Apesar desses resultados iniciais encorajadores, dado o pequeno número de casos, serão necessários mais estudos com um maior período de acompanhamento.


Abstract Background Left atrial appendage (LAA) closure has been an alternative to oral anticoagulation (OAC) for stroke prevention in patients with non-valvular atrial fibrillation (NVAF). Objectives To report the first results of an initial multicenter experience in Brazil and to investigate the feasibility, safety, and efficacy of LAA closure with the new LAmbre device. Methods We collected procedural and follow-up data of 51 consecutive patients with non-valvular atrial fibrillation, restrictions for long-term OAC and suitable anatomy that underwent LAA closure with the LAmbre device in 18 centers in Brazil. Procedural indications were significant bleeding under OAC (47.1%), stroke or persistent LAA thrombus despite OAC (27.5%), bleeding plus stroke (17.6%), other clinical contraindications for OAC (5.9%), and patient's choice due to sports practice (1.9%). Results Twenty-five men (49%) and 26 women (51%), with a mean age of 76±7.7 years, mean CHA2DS2-VASc score of 4.6± 1.7 and mean HAS-BLED score of 3.4± 1.1 were studied. Procedural success rate was 100%. Procedure-related immediate complications were pericardial effusion in two patients, and immediate device embolization in one case. No large residual shunts (> 5 mm) were observed, and small shunts (<5mm) were detected in four patients by color Doppler at the end of the procedure. After a mean follow-up of 18 ± 12 months, there were no deaths, strokes nor any other major complications. Conclusion LAA occlusion with the LAmbre device was safe and effective in this small case series. Despite these encouraging initial results, the small number of cases warrants further studies with longer-term follow-up.

4.
JDS Commun ; 2(1): 35-40, 2021 Jan.
Article in English | MEDLINE | ID: mdl-36337290

ABSTRACT

Our objective was to assess the effect of treatment with GnRH or 4 increasing doses of human chorionic gonadotropin (hCG) on the ovulatory response of a first-wave dominant follicle and subsequent plasma progesterone (P4) concentrations. Lactating Holstein cows were blocked by parity (primiparous vs. multiparous) and randomly assigned to receive no treatment (control, CON; n = 147), 100 µg of GnRH (n = 144), or 1,000 (n = 138), 2,000 (n = 144), 2,500 (n = 142), or 3,300 (n = 139) IU of hCG 7 d after the last GnRH treatment (G2) of a Double-Ovsynch (DO) or Resynch protocol. Blood samples were collected and ovaries were evaluated with transrectal ultrasonography immediately before treatment and 7 d later to assess serum P4 concentrations and ovulatory response to treatment. Data were analyzed using the MIXED and GLIMMIX procedures of SAS (SAS Institute Inc., Cary, NC). Overall, ovulatory response differed and was 4.8, 79.0, 77.4, 88.9, 92.9, and 95.6% for CON, GnRH, 1,000-, 2,000-, 2,500-, and 3,300-IU hCG treatments, respectively. The increase in plasma P4 concentrations from 7 to 14 d after G2 differed among treatments and was 3.5, 5.9, 5.7, 6.6, 7.0, and 6.5 ng/mL for CON, GnRH, 1,000-, 2,000-, 2,500-, and 3,300-IU hCG treatments, respectively. In conclusion, lactating Holstein cows treated 7 d after G2 with 100 µg of GnRH or 1,000 IU of hCG had similar ovulatory responses (~78%), whereas cows treated with 2,000, 2,500, or 3,300 IU of hCG had increased ovulatory responses (~92%). Ovulatory response of cows treated with 2,000 or 2,500 IU of hCG did not differ, whereas the ovulatory response after 3,300 IU was greater than that after 2,000 IU of hCG. Plasma P4 concentrations and luteal volume 7 d after treatment were increased compared with those of untreated control cows.

5.
Actas Dermosifiliogr (Engl Ed) ; 109(1): 47-51, 2018.
Article in English, Spanish | MEDLINE | ID: mdl-29066323

ABSTRACT

BACKGROUND: Histological diagnosis of a clinically suspected nonmelanoma skin cancer (NMSC) is recommended before treatment. For NMSC, concordance between the histological subtype of the preoperative biopsy and the excision specimen of basal cell carcinoma (BCC) has been reported to range from 10% to 81%. No large study on the concordance between NMSC histology seen in a preoperative biopsy with the following tumour specimen from Mohs micrographic surgery (MMS) has been performed in a Latin American population. OBJECTIVE: The aim of this study was to analyse and compare the histological subtype of the incisional biopsies reviewed by the dermatopathologist with the histological subtype of the tumour specimen obtained during MMS interpreted by the dermatopathologist and the Mohs surgeon. METHODS: A retrospective analysis of 320 NMSC was performed. The interobserver correlation was based on kappa values. RESULTS: The mean weighted kappa value between the preoperative NMSC biopsy and intraoperative histological subtype of the tumour specimen from MMS analysed by the Mohs surgeon and the dermatopathologist was 0.22 and 0.24, respectively. The correlation in the histologic subtype of the intraoperative tumour specimen from MMS that was interpreted by the dermatopathologist and Mohs surgeon was 0.58. CONCLUSIONS: Dermatologists need to be aware of the limited value of incisional biopsies to accurately diagnose the histological subtype of a NMSC. The concordance rate in the histological diagnosis of the tumour specimens that were obtained from MMS between the Mohs surgeon and the dermatopathologist is moderate. However, the correlation is low compared with incisional biopsy subtypes.


Subject(s)
Biopsy , Carcinoma, Basal Cell/pathology , Mohs Surgery , Skin Neoplasms/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Carcinoma, Basal Cell/classification , Carcinoma, Basal Cell/surgery , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/surgery , Child , Facial Neoplasms/pathology , Facial Neoplasms/surgery , Female , Humans , Male , Middle Aged , Observer Variation , Retrospective Studies , Skin Neoplasms/surgery , Young Adult
6.
Hematology ; 22(5): 286-291, 2017 Jun.
Article in English | MEDLINE | ID: mdl-27960630

ABSTRACT

OBJECTIVES: Acute lymphoblastic leukemia (ALL) is a clonal disease that accounts for 20% of acute leukemias in adults. A high percentage of adult patients (ranging from 70 to 80%) reach complete remission; however, the 5-year survival rate is only 20-40%. One of the main obstacles to treatment success is the drug resistance of leukemic cells. Therefore, our research group analyzed the ABCB1 and ABCG2 gene expression levels in 61 patients diagnosed with ALL and assessed whether the levels affected the clinical parameters and 40-month survival rate. METHODS: The ABCB1 and ABCG2 gene expression levels were analyzed using real-time polymerase chain reaction in 61 patients diagnosed with ALL and 99 healthy donors as controls. The association between ABCB1 and ABCG2 gene expression levels and clinical variables was determined using the Chi-square test and Fisher's exact test. Overall survival (OS) was determined using the Kaplan-Meier method. RESULTS: The results showed high ABCB1 and ABCG2 gene levels, which were 4.5 and 2.3 times the levels of healthy donors, respectively. A total of 52% of the study patients expressed high ABCB1 levels and were significantly associated with the high-risk patient group and a decreased 40-month survival rate of 78%. Only 49% of the patients expressed high ABCG2 gene levels. No association was found between the clinical parameters and the ABCG2 gene expression levels. CONCLUSIONS: Early detection of ABCB1 gene expression levels could be important for the diagnosis and monitoring of ALL patients.


Subject(s)
ATP Binding Cassette Transporter, Subfamily G, Member 2/biosynthesis , Gene Expression Regulation, Neoplastic , Neoplasm Proteins/biosynthesis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism , Precursor Cell Lymphoblastic Leukemia-Lymphoma/mortality , ATP Binding Cassette Transporter, Subfamily B/biosynthesis , Adolescent , Adult , Disease-Free Survival , Female , Humans , Male , Middle Aged , Survival Rate
7.
Arch Virol ; 159(9): 2519-21, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24719196

ABSTRACT

Sequencing of the complete genome of a raspberry bushy dwarf virus isolate from Rubus glaucus in Ecuador revealed that its RNA-1 and RNA-2 were 5449 and 2231 nucleotides (nt) long, respectively, and phylogenetically closest to isolates from Sweden and Slovenia. In dsRNA analysis of infected plants, an additional band of 3 kbp was observed. Sequencing of this band revealed that it was 3279 nt long. BLAST searches revealed that this band contained a modified version of RNA-2, which consisted of RNA-2 (2231 nt) plus an additional 1048-nt fragment that was concatenated in a reverse-complement fashion to its 5' terminus.


Subject(s)
Plant Diseases/virology , RNA Viruses/genetics , RNA Viruses/isolation & purification , RNA, Viral/genetics , Recombination, Genetic , Rosaceae/virology , Animals , Cluster Analysis , Ecuador , Molecular Sequence Data , Phylogeny , Sequence Analysis, DNA
8.
Plant Dis ; 98(9): 1267, 2014 Sep.
Article in English | MEDLINE | ID: mdl-30699660

ABSTRACT

A bacterial disease of maize, bacterial stalk and top rot, was found in the state of Morelos in February 2011, and in the state of Puebla in July 2013, Mexico. In both cases, the incidence of diseased plants was lower than 0.5%. The typical symptoms were a soft rot and darkening of the tissues affecting the stalk and the top of the plant, causing breaking of the stalk. The lesions progressed from the top to below nodes, leaf sheaths and blades, and rotten tissues emitted an unpleasant odor. Eleven diseased plants were collected, and bacterial colonies were isolated from fragments detached from the edges of symptomatic tissues after sterilization with a 0.5% solution of NaClO for 30 s, rinsing three times in sterile water. The sterilized fragments were macerated in drops of distilled sterile water for 10 min and the extract was streaked on King's medium B (agar 15 g, distilled water 1,000 ml, proteose peptone 20 g, K2HPO4 1.5 g, MgSO4·7H2O 1.5 g, glycerol 10 ml). Eight representative strains from Morelos and five from Puebla were selected for identification. All strains were gram-negative, grew at 37°C, showed pectynolitic activity on potato tubers, were positive for indole production, utilized arabinose, galactose, glucose, glycerol, lactose, mannose, melibiose, rafinose, ribose, and sucrose but did not produce acid from arabitol, adonitol, and keto-methyl-glucoside (3,4). Pathogenicity tests were conducted with each strain by inoculating with a syringe four 25-day-old maize seedlings with 107 CFU ml-1 bacterial cells in the leaf collar. Plants were incubated in the greenhouse at 30°C during the day and 24°C during the night with a 12-h photoperiod, and relative humidity of 93%. The reference strains Erwinia chrysanthemi pv zeae ATTC29942 and Dickeya zeae CFBP 2052 were used as positive controls in laboratory and greenhouses tests. Sterile water was used as negative control. Two days after inoculation, soft stalk rot symptoms developed that were identical to those observed in the field. No symptoms were observed on the negative controls. Diagnostic amplification of DNA by conventional PCR was carried out and yielded the expected amplicon size of 420 bp of the Dickeya-specific pel gene with the ADE primers set (2). PCR was used to amplify the 16S rRNA gene with the universal primers 27f and 1495r (5) for molecular identification of the 13 strains (GenBank Accession Nos. KJ438941, KJ438942, KJ438943, KJ438944, KJ438945, KJ438946, KJ438947, KJ438948, KJ438949, KJ438950, KJ438951, KJ438952, and KJ438953). The strains D. zeae CFBP 2052 and E. chrysanthemi pv. zeae ATCC 29942 were sequenced as positive controls. A BLAST search with the 13 16S rRNA gene sequences of 1.4 kb were 99% identical to the sequence of D. zeae CFBP 2052 (NR_041923). D. zeae can be a major disease of maize in tropical and subtropical countries. It is particularly severe under conditions of high temperature and high humidity, but it occurs sporadically. Control of the vector, Chilo partellus, can aid disease management (1). To our knowledge, this is the first report of D. zeae causing maize stalk rot in Mexico. References: (1) CABI. Crop Prot. Compend. CAB International, Wallingford, UK, 2014. (2) A. Nassar et al. Appl. Environ. Microbiol. 62:2228, 1996. (3) R. Samson et al. Int. J. Syst. Evol. Microbiol. 55:1415, 2005. (4) N. W. Schaad et al. Laboratory Guide for Identification of Plant Pathogenic Bacteria. 3rd ed. APS Press, St. Paul, MN, 2001. (5) W. G. Weisburg. J. Bacteriol. 173:697, 1991.

9.
Plant Dis ; 98(11): 1577, 2014 Nov.
Article in English | MEDLINE | ID: mdl-30699826

ABSTRACT

Burkholderia gladioli is one of the causal agents of bacterial panicle blight of rice (BPB). Although B. glumae is considered the main pathogen responsible of BPB, B. gladioli can also cause this disease in rice (3). B. gladioli is also of clinical importance because of the ability of some strains to cause respiratory infections in humans (2). Symptoms in rice plantations of Palestina city, like upright panicles with grayish-straw color, grain rot, and vain grains were observed in July 2013, although similar symptoms were first noticed as early as 2012 in other regions of Ecuador. Since then, similar symptomatology has been reported by farmers in coastal provinces, possibly affecting 75% of the crops. One of the causal agents was recently identified as B. glumae but other bacteria were observed in infected rice (1). Plants showing BPB symptoms were collected from Palestina and bacteria were isolated from panicle twigs using the semi selective SPG agar (KH2PO4 1.3 g, Na2HPO4 1.2 g, (NH4)2SO4 5 g, MgSO4·7H2O 0.25 g, Na2MoO4·2H2O 24 mg, EDTA-Fe 10 mg, L-cystine 10 µg, D-sorbitol 10 g, pheneticillin potassium 50 mg, ampicillin sodium 10 mg, cetrimide 10 mg, methyl violet 1 mg, phenol red 20 mg, agar 15 g/liter distilled water). Colonies were then transferred to PDA. Presumptive B. gladioli colonies were classified into two groups according to their color on PDA. Colonies from group one (six strains) were dull yellow, whereas those from group two (two strains) were olive colored. Both groups produced fluorescent colonies with smooth, shiny surfaces on PDA. All cells were gram-negative rods with the following dimensions: 0.8 to 2.0 × 0.4 to 0.6 µm (group one) or 1.5 to 2.5 × 0.4 to 0.7 µm (group two). All colonies were subjected to biochemical tests (API 20NE) and shared a 99% or higher similarity (APIWEB) with B. gladioli. To confirm identity, genomic DNA was extracted (gDNA extraction kit from Invitrogen) and a portion of the 16s rDNA was amplified by PCR using the primers 536F: 5'-GTGCCAGCMGCCGCGGTAATAC-3' and 1492R: 5'-GGTTACCTTGTTACGACTT-3' followed by sequencing. Sequences of group one strains shared 100% similarity with B. gladioli strain OM1 (GenBank Accession No. EU678361) while the sequences from group two strains were 100% similar to B. gladioli strain BgHL-01 (JX566503). Sequences of the Ecuadorian strains were deposited into NCBI GenBank (group one: KF669879 to KF669882, KF669884, and KF669885; group two: KF669883 and KF669886). Pathogenicity was confirmed by submerging rice seeds in a cell suspension with 108 CFU of the pathogen for 24 h. Seeds were germinated at 28°C and about 70% RH on autoclaved peat. Inoculated seeds yielded plants with BPB symptoms 6 days after planting. Re-isolated strains shared a 99.9% similarity with B. gladioli by APIWEB. To the best of our knowledge, this is the first report of B. gladioli as a rice pathogen in Ecuador. References: (1) C. Riera-Ruiz et al. Plant Dis. 98:988, 2014. (2) C. Segonds et al. J. Clin. Microbiol. 47:1510, 2009. (3) H. Ura et al. J. Gen. Plant Pathol. 72:98, 2006.

10.
Plant Dis ; 98(7): 988, 2014 Jul.
Article in English | MEDLINE | ID: mdl-30708859

ABSTRACT

Rice (Oryza sativa L.) is one of the leading crops and the basis of most diets in Ecuador and other countries. Diseases such as bacterial panicle blight (BPB), also known as seedling rot or grain rot, have the potential to threaten rice production worldwide. Burkholderia glumae, a causal agent of BPB, has severely affected the rice industry in many countries of Africa, Asia, and the Americas (1,2,4), but no report of this bacteria in Ecuador can be found in the literature. Rice plantations showing BPB-like symptoms including upright panicles with stained and vain grains were spotted in Palestina city, one of Ecuador's most extensive rice areas, in July 2013, but similar symptoms have been observed in the region since early 2012. Six symptomatic plants from two different groves were collected. Samples were plated on the semi-selective medium S-PG (KH2PO4 1.3 g, Na2HPO4 1.2 g, (NH4)2SO4 5 g, MgSO4·7H2O 0.25 g, Na2MoO4·2H2O 24 mg, EDTA-Fe 10 mg, L-cystine 10 µg, D-sorbitol 10 g, pheneticillin potassium 50 mg, ampicillin sodium 10 mg, cetrimide 10 mg, methyl violet 1 mg, phenol red 20 mg, agar 15 g/liter distilled water) and axenic colonies were transferred to potato dextrose agar (PDA) to test for fluorescence (3). Colonies of the potential pathogen were 1 mm, circular, entire margin, with a smooth and shiny surface. When cultured in PDA, isolates showed a moist texture, dull yellow color, and displayed fluorescence with exposure to UV light. Cells were bacterial gram-negative rods of 1 to 2 × 0.5 µm. Twelve presumptive isolates were submitted to biochemical tests (API 20NE). The biochemical profile (APIWEB) showed that all the isolates belonged to the Burkholderia genus with a 99.9% similarity. To determine the bacterial species, colonies were submitted to ELISA tests using specific antibodies for B. glumae from Agdia, Inc. The two isolates that were positive for B. glumae were sequenced using a part of the 16s rDNA amplified by the primers 536F: 5'-GTGCCAGCMGCCGCGGTAATAC-3' and 1492R: 5'-GGTTACCTTGTTACGACTT-3'. The obtained sequences (deposited into GenBank as KF601202) shared 100% similarity with several B. glumae strains after a BLAST query. Isolates were then diluted to 108 UFC/ml and used to inoculate healthy rice plants. Inoculated plants produced BPB-like symptoms including upright panicles with stained vain grains and the bacterium was re-isolated from symptomatic plants. To the best of our knowledge, this is the first report of B. glumae in Ecuador. Further research is ongoing to identify and determine the pathogenicity of the remaining Burkholderia strains that tested negative for B. glumae. References: (1) J. Luo et al. Plant Dis. 91:1363, 2007. (2) R. Nandakumar et al. Plant Dis. 93:896, 2009. (3) T. Urakami et al. Int. J. Syst. Bacteriol. 44:235, 1994. (4) X.-G. Zhou. Plant Dis. 98:566, 2014.

11.
Nature ; 503(7474): 91-4, 2013 Nov 07.
Article in English | MEDLINE | ID: mdl-24077116

ABSTRACT

The enormous size and cost of current state-of-the-art accelerators based on conventional radio-frequency technology has spawned great interest in the development of new acceleration concepts that are more compact and economical. Micro-fabricated dielectric laser accelerators (DLAs) are an attractive approach, because such dielectric microstructures can support accelerating fields one to two orders of magnitude higher than can radio-frequency cavity-based accelerators. DLAs use commercial lasers as a power source, which are smaller and less expensive than the radio-frequency klystrons that power today's accelerators. In addition, DLAs are fabricated via low-cost, lithographic techniques that can be used for mass production. However, despite several DLA structures having been proposed recently, no successful demonstration of acceleration in these structures has so far been shown. Here we report high-gradient (beyond 250 MeV m(-1)) acceleration of electrons in a DLA. Relativistic (60-MeV) electrons are energy-modulated over 563 ± 104 optical periods of a fused silica grating structure, powered by a 800-nm-wavelength mode-locked Ti:sapphire laser. The observed results are in agreement with analytical models and electrodynamic simulations. By comparison, conventional modern linear accelerators operate at gradients of 10-30 MeV m(-1), and the first linear radio-frequency cavity accelerator was ten radio-frequency periods (one metre) long with a gradient of approximately 1.6 MeV m(-1) (ref. 5). Our results set the stage for the development of future multi-staged DLA devices composed of integrated on-chip systems. This would enable compact table-top accelerators on the MeV-GeV (10(6)-10(9) eV) scale for security scanners and medical therapy, university-scale X-ray light sources for biological and materials research, and portable medical imaging devices, and would substantially reduce the size and cost of a future collider on the multi-TeV (10(12) eV) scale.


Subject(s)
Acceleration , Electrons , Lasers , Particle Accelerators/instrumentation , Aluminum Oxide , Diagnostic Imaging/instrumentation , Equipment Design , X-Rays
12.
Plant Dis ; 97(7): 1003, 2013 Jul.
Article in English | MEDLINE | ID: mdl-30722549

ABSTRACT

Banana bract mosaic virus (BBrMV), a member of the genus Potyvirus, family Potyviridae, is the causal agent of bract mosaic disease. The disorder has been considered a serious constraint to banana and plantain production in India and the Philippines, where the virus was first identified (3). To date, the presence of BBrMV has been reported only in a few banana-growing countries in Asia (3). In the Americas, BBrMV has been detected by ELISA tests in Colombia only (1). The efficient spread of BBrMV through aphids and vegetative material increases the quarantine risk and requires strict measures to prevent entrance of the virus to new areas. In Ecuador-the world's number one banana exporter-the banana industry represents the main agricultural income source. Thus, early detection of banana pathogens is a priority. In June of 2012, mosaic symptoms in bracts and bunch distortion of 'Cavendish' banana were observed in a commercial field in the province of Guayas, Ecuador. Leaves from 35 symptomatic plants were tested for Cucumber mosaic virus (CMV), Banana streak virus (BSV), and BBrMV using double antibody sandwich ELISA kits from Adgen (Scotland, UK). Twenty-one plants tested positive for BBrMV but not for CMV or BSV. In order to confirm the ELISA results, fresh or lyophilized leaf extracts were used for immunocapture reverse transcription (IC-RT)-PCR. In addition, total RNA was extracted from the ELISA-positive samples and subjected to RT-PCR. The RT reactions were done using both random and oligo dT primers. Several sets of primers, flanking conserved regions of the virus coat protein (CP), have been used for PCR-detection of BBrMV (2,3,4). The Ecuadorian BBrMV isolate was successfully detected by three primer sets with reported amplification products of 324, 280, and 260 nucleotides long, respectively (3,4). Amplification products of the expected size were purified and sequenced. All the nucleotide sequences obtained from 20 PCR-positive symptomatic plants were 100% identical between each other. However, 99% identity was observed when PCR products from the Ecuadorian isolate were compared with the corresponding fragment of a BBrMV isolate from the Philippines (NCBI Accession No. DQ851496.1). PCR products of the Ecuadorian isolate, amplified by the different CP primers described above, were assembled into a 408-bp fragment and deposited in the NCBI GenBank (KC247746). Further testing confirmed the presence of BBrMV in symptomatic plants from four different provinces. To our knowledge, this is the first report of BBrMV in Ecuador and the first BBrMV partial nucleotide sequence reported from the Americas. It is worth mentioning that primer set Bract 1/Bract 2, which amplifies a 604-bp product (2), was not effective in detecting the Ecuadorian isolate. It is hypothesized that nucleotide variation at the reverse primer site is the cause of the lack of amplification with this primer set, since the forward primer is part of the sequenced product and no variation was found. Sequencing of the entire CP region is underway to conduct phylogenetic analysis and determine genetic relationships across several other BBrMV isolates. References: (1) J. J. Alarcon et al. Agron 14:65, 2006. (2) M. F. Bateson and J. L. Dale. Arch. Virol 140:515, 1995. (3) E. M. Dassanayake. Ann. Sri Lanka Dept. Agric. 3:19, 2001. (4) M. L. Iskra-Caruana et al. J. Virol. Methods 153:223, 2008.

13.
Plant Dis ; 97(7): 1003, 2013 Jul.
Article in English | MEDLINE | ID: mdl-30722554

ABSTRACT

During the past two decades, several viruses have been identified from Rubus spp. in wild and commercial plantings around the world (2). In Ecuador, approximately 14 tons of blackberries are produced each year from an estimated area of 5,500 ha. In 2012, a preliminary survey was conducted to determine the presence of RNA viruses in Rubus glaucus, the most prevalent blackberry in Ecuador. Fifteen plants showing leaf mottling and severe mosaic were leaf-sampled from each of five different fields in Azuay Province. A total of 12 pooled samples of 20 g were obtained from the collected symptomatic tissue and used for dsRNA extraction using a cellulose-based protocol for detection of RNA viruses in plants (3). Three dsRNA segments of approximately 5 kbp, 2 kbp, and 900 bp were observed from all 12 dsRNA preparations. The dsRNA was heat-denatured and used as template for the generation of cDNA library using the universal random primer 5'-GCCGGAGCTCTGCAGAATTCNNNNNN-3', for reverse transcription (RT), and the anchor primer 5'-GCCGGAGCTCTGCAGAATTC-3'for PCR as described (1). The PCR products were cloned using a StrataClone Kit (Agilent, CA) and sequenced (Macrogen, Korea). Sequence analysis revealed the presence of Raspberry bushy dwarf virus (RBDV), a pollen-borne Idaeovirus naturally found in several Rubus spp. worldwide. Approximately 120 RBDV sequences obtained from the Ecuadorean isolate were assembled into two contigs belonging to RNA1 and RNA2. Both sequences were re-confirmed by RT-PCR using specific primers. Partial sequences were assigned GenBank Accessions KC315894, KC315893, and KC315892 for the replicase, MP and CP, respectively. Furthermore, BLAST searches showed that the nucleotide sequence corresponding to the replicase was 95% similar to an isolate from the resistance breaking R15 strain (S51557.1), whereas the MP and CP nucleotide sequences were up to 98% similar to a Slovenian isolate (EU796088.1). Primers designed to amplify a 427-bp portion of the CP were used to detect RBDV from four blackberry plantings in two distant production areas: Ambato in Tungurahua Province and Paute in Azuay Province. Leaf mottling and severe mosaic was observed in 90% of blackberry fields in those two locations. Leaf samples (n = 90) were randomly collected from both symptomatic and asymptomatic plants in each location. In Ambato, RBDV was detected in 50% and 40% of symptomatic and asymptomatic plants, respectively. In Paute, RBDV was present in 70% of symptomatic plants and 29% of asymptomatic plants. The presence of RBDV in asymptomatic plants suggests the virus might not be the sole causal agent of the disorder. Further studies are needed to determine the role of RBDV in the observed symptoms, since virus complexes responsible for increased severity of symptoms have been commonly reported in Rubus spp. (4). R. glaucus is native to the tropical highlands (from Ecuador to Mexico) and differs from blackberries commercially grown in the United States and Europe. Therefore, RBDV-induced symptoms reported in blackberry grown in the United States and Europe may not be extrapolated to the Andes berry. To the best of our knowledge, this is the first report of RBDV from blackberry in Ecuador. References: (1) P. Froussard. Nucleic Acids Res. 20:2900, 1992. (2) R. R. Martin et al. Plant Dis. 97:168, 2013. (3). T. J. Morris and J. A. Dodds. Phytopathology 69:854. 1979. (4) D. F. Quito-Avila et al. J. Virol. Methods 179:38, 2012.

14.
Oncol Lett ; 4(3): 461-466, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22970044

ABSTRACT

Acute myeloid leukaemia results from the neoplastic transformation of haematopoietic stem cells. Although advances have been made in its treatment, the mortality rate remains high. As a result, therapeutic alternatives continue to be explored. In this study, we present evidence that suggests that casein, the principal protein in milk, possesses significant antileukaemic properties. We investigated whether casein inhibited the in vitro proliferation and induced the apoptosis of the mouse myelomonocytic leukaemia cell line WEHI-3. By contrast, under identical conditions, casein markedly promotes the proliferation of mouse normal mononuclear bone marrow cells. Since the selective elimination of leukaemia cells is an ideal therapeutic strategy, we also evaluated the antileukaemic potential of casein in vivo. The results showed that casein increases the survival of mice bearing WEHI-3-induced tumours, suggesting that this molecule is also capable of inhibiting the proliferation of these cells in vivo. The evidence that casein inhibited cell proliferation and induced apoptosis in leukaemia cells in vitro, but increased survival in vivo in a leukaemia mouse model, indicates that casein may be useful in leukaemia therapy.

17.
Phys Rev Lett ; 101(8): 085002, 2008 Aug 22.
Article in English | MEDLINE | ID: mdl-18764625

ABSTRACT

Laser-driven, quasimonoenergetic electron beams of up to approximately 200 MeV in energy have been observed from steady-state-flow gas cells. These beams emitted within a low-divergence cone of 2.1+/-0.5 mrad FWHM display unprecedented shot-to-shot stability in energy (2.5% rms), pointing (1.4 mrad rms), and charge (16% rms) owing to a highly reproducible gas-density profile within the interaction volume. Laser-wakefield acceleration in gas cells of this type provides a simple and reliable source of relativistic electrons suitable for applications such as the production of extreme-ultraviolet undulator radiation.

18.
Leuk Res ; 32(10): 1518-22, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18455790

ABSTRACT

This study was conducted to determine the frequency of the most common fusion genes in Mexican pediatric patients with acute lymphoblastic leukemia (ALL). Molecular analysis using RT-PCR was carried out in 53-blood samples: 52 patients with de novo ALL and one with relapsed ALL. The ETV6-RUNX1 fusion was found in 7 cases (13.5%), BCR-ABL fusion was detected in 2 cases (3.8%), and 6 patients (11.5%) expressed the chimeric gene E2A-PBX1. The prevalence of E2A-PBX1 is one of the highest that has been described thus far in childhood ALL. Furthermore, we detected both the BCR-ABL, and E2A-PBX1 fusion in the relapsed patient. With regards to the immunophenotype, ETV6-RUNX1 was expressed in both pre-B and T-cell cases, while the presence of E2A-PBX1 and BCR-ABL was associated with the pre-B ALL phenotype. The prevalence of E2A-PBX1 in Mexican pediatric cases supports the existence of ethnic differences in the frequency of molecular markers of ALL.


Subject(s)
Core Binding Factor Alpha 2 Subunit/genetics , Fusion Proteins, bcr-abl/genetics , Homeodomain Proteins/genetics , Oncogene Proteins, Fusion/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Proto-Oncogene Proteins c-ets/genetics , Repressor Proteins/genetics , Adolescent , Child , Child, Preschool , Female , Gene Frequency , Humans , Infant , Male , Mexico , Precursor Cell Lymphoblastic Leukemia-Lymphoma/ethnology , ETS Translocation Variant 6 Protein
19.
J Dairy Sci ; 91(1): 11-9, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18096920

ABSTRACT

Antioxidant active packaging consisting of coextruded films made of low density polyethylene (LDPE) added with 0, 8, and 14 mg/g of butylated hydroxytoluene (BHT) and polyamide 6/66 were fabricated. The release of BHT from the films to Asadero cheese was determined. Most of the BHT was diffused from the LDPE layer to the cheese during the first 20 d of storage at 5 degrees C. Diffusion coefficient for the diffusion of BHT from the films 8 and 14 to the cheese was calculated as 6.24E-12 and 6.26E-12 cm2/s, respectively. The release of BHT from the film added with 8 mg/g of the antioxidant in the LDPE layer complied with the legal limit established for food products. However, the film added with 14 mg/g of the antioxidant exceeded that limit. The film added with 8 mg/g of BHT maintained the same levels of oxidized odor from 20 to 100 d of storage.


Subject(s)
Antioxidants/chemistry , Butylated Hydroxytoluene/chemistry , Cheese/analysis , Food Packaging/methods , Odorants/analysis , Polyethylene/chemistry , Food Packaging/standards , Humans , Oxidation-Reduction , Random Allocation
20.
Food Addit Contam ; 22(9): 892-8, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16192075

ABSTRACT

The effect of heat processing, storage time and temperature on the migration of bisphenol A (BPA) from organosol and epoxy can coatings to a fatty-food simulant and tuna was determined. Analyses of BPA were performed by RP-HPLC with fluorescence detection. Four migration experiments, performed between 2000 and 2003, using cans with organosol, epoxy and a combination of both types of coatings were performed under different processing conditions and storage times. Migration levels as high as 646.5 microg kg(-1) BPA from an organosol coating of tuna fish cans were found using a fatty-food simulant following the heat processing of the simulant-filled cans. Levels ranging from 11.3 to 138.4 microg kg(-1) BPA from tuna cans coated with an epoxy resin migrated to the fatty-food simulant during 1 year at 25 degrees C. Levels of BPA migration into a fatty-food simulant from thermally processed and stored tuna cans coated with a combination of organosol and epoxy resins and from vegetable cans coated with an epoxy resin were below the limit of quantitation of 10.0 microg kg(-1). Migration of BPA to tuna ranged from <7.1 to 105.4 microg kg(-1) during long-term storage at 25 degrees C. BPA levels in tuna cans purchased from three local supermarkets ranged from <7.1 to 102.7 microg kg(-1). The highest migration levels were found following heat processing at temperatures as high as 121 degrees C and at times as long as 90 min. Coatings from different can batches can give different levels of BPA migration. The migration levels of BPA found in this work are below the present European Union migration limit, except the 646.5 microg kg(-1) found after the commercial heating process was applied to the simulant-filled cans coated with the organosol resin.


Subject(s)
Food Contamination/analysis , Food Packaging , Phenols/chemistry , Seafood/analysis , Tuna , Animals , Benzhydryl Compounds , Chromatography, High Pressure Liquid/methods , Diffusion , Epoxy Resins , Food Analysis/methods , Temperature
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