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Silva WA, Costa MC, Valente V, Sousa JF, Paçó-Larson ML, Espreafico EM, Camargo SS, Monteiro E, Holanda AJ, Zago MA, Simpson AJ, Dias Neto E. PCR template preparation for capillary DNA sequencing. Biotechniques 2001; 30:537, 540-2. [PMID: 11256382 DOI: 10.2144/01303st05] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Fluorescence-based capillary DNA sequencing has facilitated the early completion of several complex sequencing projects. While capillary systems offer great benefits in terms of ease of use and automation, we find that they are sufficiently different from slab gel separation methodologies, demanding re-examination of the protocols used to generate and use DNA sequencing templates. We have recently initiated a large-scale Human Open Reading Frame EST project involving 30 laboratories feeding 11 MegaBace 1000 capillary sequencers. The group has already produced more than 300,000 valid sequences. The most successful template preparation protocol we have found is described here. We have found that a crucial step is the standardization of the quantity and quality of the templates, which have been achieved by overnight bacterial culture followed by PCR using limiting amounts of primers. Using this protocol, there is no need for post-PCR purification, and the final preparation cost is US $0.09/template. After sequencing 10,848 templates using this protocol, 78% of the reads were accepted (after discarding vectors without inserts and inserts smaller than 100 nucleotides), and 85% of the total number of bases had Phred scores of 15 or above.
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Jannotti-Passos LK, Souza CP, Parra JC, Simpson AJ. Biparental mitochondrial DNA inheritance in the parasitic trematode Schistosoma mansoni. J Parasitol 2001; 87:79-82. [PMID: 11227906 DOI: 10.1645/0022-3395(2001)087[0079:bmdiit]2.0.co;2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The maternal inheritance of mitochondrial DNA (mtDNA) in eukaryotic organisms occurs because of the selective destruction of paternal mtDNA molecules that may be present in the zygote. The elimination of sperm mtDNA is less efficient in interspecific crosses, and biparental inheritance of mtDNA has been observed in a variety of species. Because interspecific crosses are likely to be extremely rare in nature, parental inheritance of mtDNA has been deemed of little relevance to population genetics. The mtDNA of the parasitic trematode Schistosoma mansoni was examined for its utility in addressing epidemiological questions related to the transmission and spread of schistosomiasis. Prior to embarking on such experiments, we sought to confirm the mode of inheritance of this molecule using the highly polymorphic mtDNA minisatellite as a marker. In 3 separate crosses, mtDNA apparently identical to paternal DNA was observed in some individuals of the F2 and F3 generations. These observations thus suggest the intraspecific paternal inheritance of mtDNA across multiple generations in Schistosoma mansoni.
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78
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Simpson AJ, Caballero OL, Pena SD. Microsatellite instability as a tool for the classification of gastric cancer. Trends Mol Med 2001; 7:76-80. [PMID: 11286759 DOI: 10.1016/s1471-4914(01)01916-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Microsatellite instability (MSI) is a common feature of gastric cancers that reflects underlying mismatch-repair deficiency in the tumor, caused most frequently by methylation of the hMLH1 promoter. Tumors with MSI have been found to inactivate certain target genes by permitting an increased frequency of mutations in mononucleotide runs in their coding regions. Gastric tumors with MSI have a distinct clinicopathological profile with a relatively good prognosis. Using the simple and robust methodologies available, MSI detection in gastrointestinal tumors promises to be one of the first widely used molecular prognostic tests for human cancer. Here, we review the molecular context of this exciting prospect with respect to one of the world's most prevalent cancers, that of the stomach.
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79
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Silva CC, Giongo V, Simpson AJ, Camargos ER, Silva JL, Koury MC. Effects of hydrostatic pressure on the Leptospira interrogans: high immunogenicity of the pressure-inactivated serovar hardjo. Vaccine 2001; 19:1511-4. [PMID: 11163675 DOI: 10.1016/s0264-410x(00)00361-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The Hardjoprajitno strain of Leptospira interrogans serovar hardjo was subjected to different hydrostatic pressures. Complete inactivation occurred when the leptospires were treated with 2 kbar for 60 min. Electron microscopy showed dislocation of the outer membrane, partial loss of the helical shape and extrusion of the axial filament from the cytoplasmic cylinder of the pressurized leptospires. When the pressure-treated leptospires were inoculated into rabbits they were highly immunogenic. The sera of these animals presented a titer of 2048 in the microscopic serum agglutination reaction. Fluorescence measurements indicated that the action of pressure on the leptospires might have resulted from perturbation on membrane protein components, permitting the binding of the fluorescent probe bis (8-anilinonaphthalene-1-sulfonate) (Bis-ANS). This is the first report of the use of hydrostatic pressure to inactivate pathogenic bacteria with the potential to lead to a vaccine.
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80
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Paton NI, Angus B, Chaowagul W, Simpson AJ, Suputtamongkol Y, Elia M, Calder G, Milne E, White NJ, Griffin GE. Protein and energy metabolism in chronic bacterial infection: studies in melioidosis. Clin Sci (Lond) 2001; 100:101-10. [PMID: 11115424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Chronic infection is often accompanied by a wasting process, the metabolic basis of which is not fully understood. The aims of the present study were to measure protein and energy metabolism in patients with melioidosis (a serious and antibiotic-refractory Gram-negative bacterial infection which is endemic in South-East Asia) in order to define the metabolic abnormalities that might contribute to wasting. Whole-body protein turnover was measured using the [(13)C]leucine technique, both in the fasted state and while consuming a high-energy meal. Resting energy expenditure was measured by indirect calorimetry, and total energy expenditure by the bicarbonate/urea method. Results were normalized for fat-free mass, as estimated from skinfold thickness. Protein turnover was increased in melioidosis patients compared with healthy controls during fasting (170.9 compared with 124.1 micromol x kg(-1) x h(-1); P=0.04), but the net rate of catabolism (22.2 compared with 20.5 micromol x kg(-1) x h(-1); P=0.77) and the anabolic response to feeding were similar in the two groups. Resting energy expenditure was higher in melioidosis patients compared with controls (191.4 and 157.3 kJ x kg(-1) x day(-1) respectively; P=0.04), but total energy expenditure (measured in a separate group of eight patients with melioidosis) was low (192.1 kJ x kg(-1) x day(-1)). In conclusion, this study found no evidence of metabolic causative factors, such as accelerated net protein catabolism during fasting, a blunted anabolic response to feeding or increased daily energy expenditure, and therefore suggests that reduced energy intake is the prime cause of wasting. The observed normal response to feeding should encourage nutritional approaches to prevent wasting.
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81
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Leite KR, Garicochea B, Srougi M, Dzik C, Nesralhah L, de Moura RC, Simpson AJ, Darini E, Carvalho CM, Camara-Lopes LH. Monoclonality of asynchronous bilateral lymphoma of the testis. Eur Urol 2000; 38:774-7. [PMID: 11111200 DOI: 10.1159/000020378] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVES Lymphoma is the most frequent testicular malignancy in men over 60 years of age. Even though patients present initially with localized disease, the high incidence of bilateral involvement, synchronous or not, and early systemic dissemination are characteristic of these neoplasms. Sometimes the interval between tumor involvement of both testes is long. The question is raised whether either the patient has a predisposition to present new clones of transformed lymphocytes, or the same disease using the same pathway from a systemic reservoir infiltrates the contralateral testis. METHOD Polymerase chain reaction and DNA sequencing were used to detect immunoglobulin heavy chain (IgH) rearrangement in paraffin-embedded specimens from asynchronous tumors affecting the right and left testis of a 85-year-old man with an interval period of 13 months. RESULTS Both tumors showed the same IgH rearrangement. CONCLUSIONS The lymphoma affecting the left and right testis derived from the same clone. It makes a strong case that lymphoma of the testis is the first manifestation of a systemic disease and should be treated aggressively early at the beginning of the disease.
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Vidigal TH, Kissinger JC, Caldeira RL, Pires EC, Monteiro E, Simpson AJ, Carvalho OS. Phylogenetic relationships among Brazilian Biomphalaria species (Mollusca: Planorbidae) based upon analysis of ribosomal ITS2 sequences. Parasitology 2000; 121 Pt 6:611-20. [PMID: 11155932 DOI: 10.1017/s0031182000006831] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In spite of their abundance, widespread distribution and medical importance, the phylogenetic relationships among Biomphalaria snails have received relatively little attention. We have collected and studied 29 populations of snails obtained from different localities from Brazil. We have sequenced the ribosomal DNA second internal transcribed spacer (ITS2) from the following Biomphalaria species: B. glabrata, B. tenagophila tenagophila, B. occidentalis, B. straminea, B. peregrina, B. kuhniana, B. schrammi, B. amazonica, B. oligoza, B. intermedia and an outgroup species Helisoma duryi. The sequence from each species is unique. Three different methods of phylogenetic reconstruction were used (distance, maximum parsimony and maximum likelihood). The resulting phylogenetic trees obtained by these methods basically support current systematic relationships based on morphological characters alone. This study demonstrates that the ITS2 region contains markers useful for identification and determination of relationships among Biomphalaria species.
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de Souza SJ, Camargo AA, Briones MR, Costa FF, Nagai MA, Verjovski-Almeida S, Zago MA, Andrade LE, Carrer H, El-Dorry HF, Espreafico EM, Habr-Gama A, Giannella-Neto D, Goldman GH, Gruber A, Hackel C, Kimura ET, Maciel RM, Marie SK, Martins EA, Nobrega MP, Paco-Larson ML, Pardini MI, Pereira GG, Pesquero JB, Rodrigues V, Rogatto SR, da Silva ID, Sogayar MC, de Fátima Sonati M, Tajara EH, Valentini SR, Acencio M, Alberto FL, Amaral ME, Aneas I, Bengtson MH, Carraro DM, Carvalho AF, Carvalho LH, Cerutti JM, Corrêa ML, Costa MC, Curcio C, Gushiken T, Ho PL, Kimura E, Leite LC, Maia G, Majumder P, Marins M, Matsukuma A, Melo AS, Mestriner CA, Miracca EC, Miranda DC, Nascimento AN, Nóbrega FG, Ojopi EP, Pandolfi JR, Pessoa LG, Rahal P, Rainho CA, da Rós N, de Sá RG, Sales MM, da Silva NP, Silva TC, da Silva W, Simão DF, Sousa JF, Stecconi D, Tsukumo F, Valente V, Zalcbeg H, Brentani RR, Reis FL, Dias-Neto E, Simpson AJ. Identification of human chromosome 22 transcribed sequences with ORF expressed sequence tags. Proc Natl Acad Sci U S A 2000; 97:12690-3. [PMID: 11070084 PMCID: PMC18825 DOI: 10.1073/pnas.97.23.12690] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Transcribed sequences in the human genome can be identified with confidence only by alignment with sequences derived from cDNAs synthesized from naturally occurring mRNAs. We constructed a set of 250,000 cDNAs that represent partial expressed gene sequences and that are biased toward the central coding regions of the resulting transcripts. They are termed ORF expressed sequence tags (ORESTES). The 250,000 ORESTES were assembled into 81,429 contigs. Of these, 1, 181 (1.45%) were found to match sequences in chromosome 22 with at least one ORESTES contig for 162 (65.6%) of the 247 known genes, for 67 (44.6%) of the 150 related genes, and for 45 of the 148 (30.4%) EST-predicted genes on this chromosome. Using a set of stringent criteria to validate our sequences, we identified a further 219 previously unannotated transcribed sequences on chromosome 22. Of these, 171 were in fact also defined by EST or full length cDNA sequences available in GenBank but not utilized in the initial annotation of the first human chromosome sequence. Thus despite representing less than 15% of all expressed human sequences in the public databases at the time of the present analysis, ORESTES sequences defined 48 transcribed sequences on chromosome 22 not defined by other sequences. All of the transcribed sequences defined by ORESTES coincided with DNA regions predicted as encoding exons by genscan. (http://genes.mit.edu/GENSCAN.html).
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84
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Nunes DN, Kowalski LP, Simpson AJ. Detection of oral and oropharyngeal cancer by microsatellite analysis in mouth washes and lesion brushings. Oral Oncol 2000; 36:525-8. [PMID: 11036246 DOI: 10.1016/s1368-8375(00)00045-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Microsatellite allele losses are characteristic features of head and neck squamous cell carcinoma and can be used as molecular markers for malignancy. We have investigated the detection of microsatellite allele loss in mouth washes and lesions brushings from 19 patients with squamous cell carcinoma of the oral cavity and oropharynx as a means of tumour detection. In 84% of the analysed cases, allele loss previously identified in the tumour of these patients, was detected in these easily obtained specimens. No alterations were found in material derived from 10 healthy individuals. Success of detection was independent of tumour stage, suggesting that this approach may be useful for early diagnosis as well as for follow-up.
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85
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Terra AP, Silva-Vergara ML, Gomes RA, Pereira CL, Simpson AJ, Caballero OL. [Monitoring AIDS patients for the development of cytomegalovirus (CMV) disease using multiplex PCR]. Rev Soc Bras Med Trop 2000; 33:583-9. [PMID: 11175589 DOI: 10.1590/s0037-86822000000600010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The human cytomegalovirus is an important pathogen in patients infected with the human immunodeficiency virus (HIV). The CMV viral load seems to be predictor of the development of the CMV disease in these patients. We used a multiplex PCR protocol that also provides quantitative information in those samples from which a single band is amplified and contains fewer viral genomes than those from which both targets are amplified. Monthly blood samples were collected from 270 AIDS patients. From twenty patients, two CMV targets were amplified three or more consecutive times and these patients developed CMV related disease during the study. In contrast, patients who did not result positive for both viral targets, for three or more consecutive times, or who had alternating positive and negative samples during the follow up did not present CMV related disease. The results suggest that the PCR multiplex can be used for the identification of HIV positive patients with higher risk of development of CMV disease.
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86
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Abath FG, Xavier EM, Allen R, Gomes YM, Lucena-Silva N, Baliza M, Simpson AJ. Characterization of Sm13, a tegumental antigen of Schistosoma mansoni. Parasitol Res 2000; 86:745-52. [PMID: 11002983 DOI: 10.1007/pl00008562] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Sm13, a 13-kDa Schistosoma mansoni tegumental antigen, is one of the principal polypeptides recognized by antibodies from mice protectively vaccinated with adult-worm tegumental membranes. To obtain the complete gene encoding Sm13 we subcloned and sequenced a cDNA and a fragment of a genomic clone. The collated sequence contains 1,088 nucleotides and represents the full-length open reading frame of the gene, encoding a protein of 104 amino acids with a calculated molecular mass of 11,923 Da, compatible with the native protein identified in the tegumental membranes. The sequence derived from genomic DNA contains a 45-nucleotide intron. The analysis of the predicted protein suggests the presence of both N- and C-terminal hydrophobic membrane-spanning segments, and the coding region contains no homology in the currently available data bases. Additionally, the coding region is preceded by putative CCAAT and TATA boxes that may be involved in the control of expression. Western-blot analysis and indirect immunofluorescence resulted in the identification of a 13-kDa protein (Sm13) in the tegument of adult worms. The present study reveals that Sm13 behaves as an integral membrane protein upon partitioning in Triton X-1 14 and that it is present in worms of 3 weeks or older but not in schistosomula or miracidia. Moreover, it is also specifically recognized by sera from some schistosomiasis patients in enzyme-linked immunosorbent assay and Western-blot analysis, suggesting that it is immunogenic in human schistosomiasis.
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87
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Bevilacqua RA, Simpson AJ. Methylation of the hMLH1 promoter but no hMLH1 mutations in sporadic gastric carcinomas with high-level microsatellite instability. Int J Cancer 2000. [PMID: 10861474 DOI: 10.1002/1097-0215(20000715)87:2<200::aid-ijc7>3.0.co;2-i] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Microsatellite instability (MSI) in tumors from patients with hereditary non-polyposis colorectal cancer (HNPCC) is caused by germline mutations in mismatch repair (MMR) genes, principally hMSH2 and hMLH1. In contrast, somatic mutations in MMR genes are relatively rare in sporadic MSI(+) colon cancers. Rather, the majority of mutation-negative, MSI(+) cases involve hypermethylation of the hMLH1 promoter and subsequent lack of expression of hMLH1. The details of the mechanisms of this epigenetic gene silencing remain to be elucidated. In some colon cancer cell lines, hMLH1 promoter methylation is accompanied by mutation of 1 of the 2 alleles, whereas in other cell lines and tumors, such combinations have not been reported. To contribute to the characterization of MSI in gastric cancer and to directly investigate whether hMLH1 promoter methylation is accompanied by gene mutation in these cancers, we have analyzed 42 gastric tumors and corresponding normal tissue for MSI, hypermethylation of the hMLH1 promoter, and mutations in hMLH1 as well as hMSH2. We found that 10 (23.8%) of 42 cases of sporadic gastric cancer were MSI(+) and that 8 had at least 2 of 12 altered microsatellite loci. All samples with at least 2 altered loci exhibited methylation of the hMLH1 promoter region, but none had detectable mutations in hMLH1 or hMSH2. Our results confirm the importance of methylation of the hMLH1 promoter region in MSI(+) gastric tumors and suggest that methylation takes place in the absence of hMLH1 mutations in these tumors.
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88
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Frohme M, Camargo AA, Heber S, Czink C, Simpson AJ, Hoheisel JD, de Souza AP. Mapping analysis of the Xylella fastidiosa genome. Nucleic Acids Res 2000; 28:3100-4. [PMID: 10931925 PMCID: PMC108426 DOI: 10.1093/nar/28.16.3100] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2000] [Revised: 06/23/2000] [Accepted: 06/23/2000] [Indexed: 11/13/2022] Open
Abstract
A cosmid library was made of the 2.7 Mb genome of the Gram-negative plant pathogenic bacterium Xylella fastidiosa and analysed by hybridisation mapping. Clones taken from the library as well as genomic restriction fragments of rarely cutting enzymes were used as probes. The latter served as a backbone for ordering the initial map contigs and thus facilitated gap closure. Also, the co-linearity of the cosmid map, and thus the eventual sequence, could be confirmed by this process. A subset of the eventual clone coverage was distributed to the Brazilian X.FASTIDIOSA: sequencing network. Data from this effort confirmed more quantitatively initial results from the hybridisation mapping that the redundancy of clone coverage ranged between 0 and 45-fold across the genome, while the average was 15-fold by experimental design. Reasons for this not unexpected fluctuation and the actual gaps are being discussed, as is the use of this effect for functional studies.
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89
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Bevilacqua RA, Simpson AJ. Methylation of the hMLH1 promoter but no hMLH1 mutations in sporadic gastric carcinomas with high-level microsatellite instability. Int J Cancer 2000; 87:200-3. [PMID: 10861474 DOI: 10.1002/1097-0215(20000715)87:2<200::aid-ijc7>3.0.co;2-i] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Microsatellite instability (MSI) in tumors from patients with hereditary non-polyposis colorectal cancer (HNPCC) is caused by germline mutations in mismatch repair (MMR) genes, principally hMSH2 and hMLH1. In contrast, somatic mutations in MMR genes are relatively rare in sporadic MSI(+) colon cancers. Rather, the majority of mutation-negative, MSI(+) cases involve hypermethylation of the hMLH1 promoter and subsequent lack of expression of hMLH1. The details of the mechanisms of this epigenetic gene silencing remain to be elucidated. In some colon cancer cell lines, hMLH1 promoter methylation is accompanied by mutation of 1 of the 2 alleles, whereas in other cell lines and tumors, such combinations have not been reported. To contribute to the characterization of MSI in gastric cancer and to directly investigate whether hMLH1 promoter methylation is accompanied by gene mutation in these cancers, we have analyzed 42 gastric tumors and corresponding normal tissue for MSI, hypermethylation of the hMLH1 promoter, and mutations in hMLH1 as well as hMSH2. We found that 10 (23.8%) of 42 cases of sporadic gastric cancer were MSI(+) and that 8 had at least 2 of 12 altered microsatellite loci. All samples with at least 2 altered loci exhibited methylation of the hMLH1 promoter region, but none had detectable mutations in hMLH1 or hMSH2. Our results confirm the importance of methylation of the hMLH1 promoter region in MSI(+) gastric tumors and suggest that methylation takes place in the absence of hMLH1 mutations in these tumors.
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90
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Simpson AJ, Reinach FC, Arruda P, Abreu FA, Acencio M, Alvarenga R, Alves LM, Araya JE, Baia GS, Baptista CS, Barros MH, Bonaccorsi ED, Bordin S, Bové JM, Briones MR, Bueno MR, Camargo AA, Camargo LE, Carraro DM, Carrer H, Colauto NB, Colombo C, Costa FF, Costa MC, Costa-Neto CM, Coutinho LL, Cristofani M, Dias-Neto E, Docena C, El-Dorry H, Facincani AP, Ferreira AJ, Ferreira VC, Ferro JA, Fraga JS, França SC, Franco MC, Frohme M, Furlan LR, Garnier M, Goldman GH, Goldman MH, Gomes SL, Gruber A, Ho PL, Hoheisel JD, Junqueira ML, Kemper EL, Kitajima JP, Krieger JE, Kuramae EE, Laigret F, Lambais MR, Leite LC, Lemos EG, Lemos MV, Lopes SA, Lopes CR, Machado JA, Machado MA, Madeira AM, Madeira HM, Marino CL, Marques MV, Martins EA, Martins EM, Matsukuma AY, Menck CF, Miracca EC, Miyaki CY, Monteriro-Vitorello CB, Moon DH, Nagai MA, Nascimento AL, Netto LE, Nhani A, Nobrega FG, Nunes LR, Oliveira MA, de Oliveira MC, de Oliveira RC, Palmieri DA, Paris A, Peixoto BR, Pereira GA, Pereira HA, Pesquero JB, Quaggio RB, Roberto PG, Rodrigues V, de M Rosa AJ, de Rosa VE, de Sá RG, Santelli RV, Sawasaki HE, da Silva AC, da Silva AM, da Silva FR, da Silva WA, da Silveira JF, Silvestri ML, Siqueira WJ, de Souza AA, de Souza AP, Terenzi MF, Truffi D, Tsai SM, Tsuhako MH, Vallada H, Van Sluys MA, Verjovski-Almeida S, Vettore AL, Zago MA, Zatz M, Meidanis J, Setubal JC. The genome sequence of the plant pathogen Xylella fastidiosa. The Xylella fastidiosa Consortium of the Organization for Nucleotide Sequencing and Analysis. Nature 2000; 406:151-9. [PMID: 10910347 DOI: 10.1038/35018003] [Citation(s) in RCA: 538] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically important plant diseases. Here we report the complete genome sequence of X. fastidiosa clone 9a5c, which causes citrus variegated chlorosis--a serious disease of orange trees. The genome comprises a 52.7% GC-rich 2,679,305-base-pair (bp) circular chromosome and two plasmids of 51,158 bp and 1,285 bp. We can assign putative functions to 47% of the 2,904 predicted coding regions. Efficient metabolic functions are predicted, with sugars as the principal energy and carbon source, supporting existence in the nutrient-poor xylem sap. The mechanisms associated with pathogenicity and virulence involve toxins, antibiotics and ion sequestration systems, as well as bacterium-bacterium and bacterium-host interactions mediated by a range of proteins. Orthologues of some of these proteins have only been identified in animal and human pathogens; their presence in X. fastidiosa indicates that the molecular basis for bacterial pathogenicity is both conserved and independent of host. At least 83 genes are bacteriophage-derived and include virulence-associated genes from other bacteria, providing direct evidence of phage-mediated horizontal gene transfer.
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91
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Lauw FN, Simpson AJ, Hack CE, Prins JM, Wolbink AM, van Deventer SJ, Chaowagul W, White NJ, van Der Poll T. Soluble granzymes are released during human endotoxemia and in patients with severe infection due to gram-negative bacteria. J Infect Dis 2000; 182:206-13. [PMID: 10882599 DOI: 10.1086/315642] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2000] [Revised: 04/13/2000] [Indexed: 11/03/2022] Open
Abstract
Extracellular release of granzymes is considered to reflect the involvement of cytotoxic T lymphocytes and NK cells in various disease states. To obtain insight into granzyme release during bacterial infection, granzyme levels were measured during experimental human endotoxemia and in patients with melioidosis, a severe infection due to gram-negative bacteria. Plasma concentrations of granzyme A (GrA) and GrB increased transiently after endotoxin administration, peaking after 2-6 h. In patients with bacteremic melioidosis, GrA and GrB levels were elevated on admission and remained high during the 72-h study period. In whole blood stimulated with heat-killed Burkholderia pseudomallei, neutralization of tumor necrosis factor, interleukin-12, or interleukin-18 inhibited granzyme secretion, which was independent of interferon-gamma. Stimulation with endotoxin and other gram-negative and gram-positive bacteria also strongly induced the secretion of granzymes, suggesting that granzyme release is a general immune response during bacterial infection. The interaction between the cytokine network and granzymes may play an important immunoregulatory role during bacterial infections.
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92
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Lauw FN, Simpson AJ, Prins JM, van Deventer SJ, Chaowagul W, White NJ, van der Poll T. The CXC chemokines gamma interferon (IFN-gamma)-inducible protein 10 and monokine induced by IFN-gamma are released during severe melioidosis. Infect Immun 2000; 68:3888-93. [PMID: 10858199 PMCID: PMC101663 DOI: 10.1128/iai.68.7.3888-3893.2000] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Gamma interferon (IFN-gamma)-inducible protein 10 (IP-10) and monokine induced by IFN-gamma (Mig) are related CXC chemokines which bind to the CXCR3 receptor and specifically target activated T lymphocytes and natural killer (NK) cells. The production of IP-10 and Mig by various cell types in vitro is strongly dependent on IFN-gamma. To determine whether IP-10 and Mig are released during bacterial infection in humans, we measured plasma levels of IP-10 and Mig in patients with melioidosis, a severe gram-negative infection caused by Burkholderia pseudomallei. IP-10 and Mig were markedly elevated in patients with melioidosis on admission, particularly in blood culture-positive patients, and remained elevated during the 72-h study period. Levels of IP-10 and Mig showed a positive correlation with IFN-gamma concentrations and also correlated with clinical outcome. In whole blood stimulated with heat-killed B. pseudomallei, neutralization of IFN-gamma and tumor necrosis factor alpha (TNF-alpha) partly attenuated IP-10 and Mig release, while anti-interleukin-12 (IL-12) and anti-IL-18 had a synergistic effect. Stimulation with other bacteria or endotoxin also induced strong secretion of IP-10 and Mig. These data suggest that IP-10 and Mig are part of the innate immune response to bacterial infection. IP-10 and Mig may contribute to host defense in Th1-mediated host defense during infections by attracting CXCR3(+) Th1 cells to the site of inflammation.
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Correa RG, de Carvalho AF, Pinheiro NA, Simpson AJ, de Souza SJ. NABC1 (BCAS1): alternative splicing and downregulation in colorectal tumors. Genomics 2000; 65:299-302. [PMID: 10857754 DOI: 10.1006/geno.2000.6172] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have identified a new splicing variant of the gene "novel amplified in breast cancer 1," NABC1 (HGMW-approved symbol BCAS1). This variant, which we call NABC1_5B, uses a previously unidentified 135-bp exon. Also in this report, we confirm that NABC1 is overexpressed in breast tumors and show that both NABC1 and NABC1_5B are downregulated in colorectal tumors.
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94
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Dias Neto E, Correa RG, Verjovski-Almeida S, Briones MR, Nagai MA, da Silva W, Zago MA, Bordin S, Costa FF, Goldman GH, Carvalho AF, Matsukuma A, Baia GS, Simpson DH, Brunstein A, de Oliveira PS, Bucher P, Jongeneel CV, O'Hare MJ, Soares F, Brentani RR, Reis LF, de Souza SJ, Simpson AJ. Shotgun sequencing of the human transcriptome with ORF expressed sequence tags. Proc Natl Acad Sci U S A 2000; 97:3491-6. [PMID: 10737800 PMCID: PMC16267 DOI: 10.1073/pnas.97.7.3491] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Theoretical considerations predict that amplification of expressed gene transcripts by reverse transcription-PCR using arbitrarily chosen primers will result in the preferential amplification of the central portion of the transcript. Systematic, high-throughput sequencing of such products would result in an expressed sequence tag (EST) database consisting of central, generally coding regions of expressed genes. Such a database would add significant value to existing public EST databases, which consist mostly of sequences derived from the extremities of cDNAs, and facilitate the construction of contigs of transcript sequences. We tested our predictions, creating a database of 10,000 sequences from human breast tumors. The data confirmed the central distribution of the sequences, the significant normalization of the sequence population, the frequent extension of contigs composed of existing human ESTs, and the identification of a series of potentially important homologues of known genes. This approach should make a significant contribution to the early identification of important human genes, the deciphering of the draft human genome sequence currently being compiled, and the shotgun sequencing of the human transcriptome.
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95
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Logullo AF, de Moura RP, Nonogaki S, Kowalski LP, Nagai MA, Simpson AJ. A proposal for the integration of immunohistochemical staining and DNA-based techniques for the determination of TP53 mutations in human carcinomas. DIAGNOSTIC MOLECULAR PATHOLOGY : THE AMERICAN JOURNAL OF SURGICAL PATHOLOGY, PART B 2000; 9:35-40. [PMID: 10718211 DOI: 10.1097/00019606-200003000-00006] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The p53 protein plays an important role in the control of the cell cycle and DNA repair. Mutations in the TP53 gene may be a prognostic factor for certain forms of human cancer, with specific mutation sites being associated with significantly worse prognosis, particularly for colorectal and breast cancer. Thus, standardization of accurate, rapid, and cost-effective techniques for the detection of TP53 mutations is a high priority. At present, the only widely available technology that reliably detects and defines all mutations is DNA sequencing. However, the routine sequencing of the entire TP53 gene in all breast and colorectal cancer cases in hospital laboratories is prohibitively costly, complex, and time consuming. In order for the analytical power of DNA to be accessed by the routine laboratory, initial screening using immunohistochemistry, which is widely used as a test for detection of accumulated, mutated protein, followed by heteroduplex analysis of exons 4 to 9 to detect frameshift mutations in immunohistochemistry-negative cases, is proposed. To illustrate the effectiveness of this approach, 28 cases of head and neck squamous-cell carcinomas that were known to contain TP53 mutations were retrospectively analyzed. All missense mutations stained positive on immunohistochemistry using the monoclonal antibody DO7, and all insertions and deletions, even those involving a single nucleotide, were positive using an extremely simple heteroduplex analysis. Only rare nonsense mutations were not detected by this strategy. Nevertheless, application of these results to published data suggests that the prescreening would detect 80% of mutations but would result in a 75% reduction in the sequencing load of the laboratory.
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96
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Simpson AJ, Opal SM, Angus BJ, Prins JM, Palardy JE, Parejo NA, Chaowagul W, White NJ. Differential antibiotic-induced endotoxin release in severe melioidosis. J Infect Dis 2000; 181:1014-9. [PMID: 10720525 DOI: 10.1086/315306] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Severe melioidosis is a life-threatening, systemic bacterial infection caused by Burkholderia pseudomallei. A prospective, randomized treatment trial was conducted in northeast Thailand to compare ceftazidime (a penicillin-binding protein [PBP]-3-specific agent that causes release of large amounts of endotoxin in vitro) and imipenem (a PBP-2-specific agent that kills B. pseudomallei more rapidly but releases low amounts of endotoxin) in severe melioidosis over a 6-h time course after the first dose of antibiotic. Despite similar clinical, microbiological, endotoxin, and cytokine measures at study entry, ceftazidime-treated patients (n=34) had significantly greater systemic endotoxin (P<.001) than patients treated with imipenem (n=34) after the first dose of antibiotic. No overall difference in mortality was observed (35% in both groups [95% confidence interval, 20%-50%]). Differential antibiotic-induced endotoxin release is demonstrable in severe melioidosis. These differences in endotoxin release did not appear to have a significant impact on survival in this group of patients.
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97
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Caldeira RL, Vidigal TH, Matinella L, Simpson AJ, Carvalho OS. Identification of planorbids from Venezuela by polymerase chain reaction amplification and restriction fragment length polymorphism of internal transcriber spacer of the RNA ribosomal gene. Mem Inst Oswaldo Cruz 2000; 95:171-7. [PMID: 10733735 DOI: 10.1590/s0074-02762000000200007] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Snails of the genus Biomphalaria from Venezuela were subjected to morphological assessment as well as polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis. Morphological identification was carried out by comparison of characters of the shell and the male and female reproductive apparatus. The PCR-RFLP involved amplification of the internal spacer region ITS1 and ITS2 of the RNA ribosomal gene and subsequent digestion of this fragment by the restriction enzymes DdeI, MnlI, HaeIII and MspI. The planorbids were compared with snails of the same species and others reported from Venezuela and present in Brazil, Cuba and Mexico. All the enzymes showed a specific profile for each species, that of DdeI being the clearest. The snails were identified as B. glabrata, B. prona and B. kuhniana.
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98
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Sturzeneker R, Bevilacqua RA, Haddad LA, Simpson AJ, Pena SD. Microsatellite instability in tumors as a model to study the process of microsatellite mutations. Hum Mol Genet 2000; 9:347-52. [PMID: 10655543 DOI: 10.1093/hmg/9.3.347] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We screened 42 sporadic gastric tumors and found that seven of them had significant microsatellite instability. These were then studied at 26 microsatellite loci, comprising di-, tri- and tetranucleotide repeats. The instability level of individual microsatellites in the tumors was found to be positively correlated with the population average heterozygosity and variance of repeat number of the microsatellite loci, as predicted by the stepwise mutation model. Moreover, as is known to occur in human populations, instability was strongly correlated with the number of repeats at each microsatellite locus and with the perfection of the reiterated sequence. These results demonstrate that microsatellite mutations in unstable tumors show similarities to germline mutations and suggest that their study may be useful in understanding the mechanisms that generate microsatellite variability in human populations. We used this model to test the claims that the microsatellite mutation process is biased towards increased size and heterozygosity with wide differences in allele sizes. These assertions were not confirmed.
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99
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Simpson AJ, Matusiewicz SP, Brown PH, McCall IA, Innes JA, Greening AP, Crompton GK. Emergency pre-hospital management of patients admitted with acute asthma. Thorax 2000; 55:97-101. [PMID: 10639524 PMCID: PMC1745682 DOI: 10.1136/thorax.55.2.97] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Little is known about the management of acute asthma prior to hospital admission. Pre-hospital treatment of patients referred to hospital with acute asthma was therefore studied in 150 patients divided into three groups: those in the Edinburgh Emergency Asthma Admission Service (EEAAS) who can contact an ambulance and present directly to respiratory services when symptoms arise (n = 38), those under continuing supervision at a hospital respiratory outpatient clinic (n = 54), and those managed solely in primary care (n = 58). METHODS Standardised admission forms detailing aspects of pre-hospital management, case records, GP referral letters, and ambulance patient transport forms were analysed. RESULTS In each group airflow obstruction had improved upon arrival at hospital, the effect being most marked in patients transported by ambulance (p<0. 001) and in those receiving nebulised beta(2) agonists prior to admission (p<0.005). However, 25% of patients arrived without having nebulised beta(2) agonists and 37% without having glucocorticoids. EEAAS patients were least likely to receive nebulised beta(2) agonists before arrival at hospital (p<0.05). This observation was attributable to a tendency for these patients to travel to hospital by car rather than by ambulance. CONCLUSIONS There is an important shortfall in administration of bronchodilators and glucocorticoids for acute asthma before arrival at hospital. Ambulances equipped with nebulised bronchodilators provide the optimal mode of transport to hospital for patients with acute asthma. In Edinburgh ambulances are not being used by a significant proportion of the population with asthma, possibly because of the mistaken belief that personal transport arrangements reduce journey time to hospital.
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100
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Simpson AJ, Smith MD, Weverling GJ, Suputtamongkol Y, Angus BJ, Chaowagul W, White NJ, van Deventer SJ, Prins JM. Prognostic value of cytokine concentrations (tumor necrosis factor-alpha, interleukin-6, and interleukin-10) and clinical parameters in severe melioidosis. J Infect Dis 2000; 181:621-5. [PMID: 10669346 DOI: 10.1086/315271] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Raised serum concentrations of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, or IL-10 are associated with mortality in patients with sepsis, but it is not known whether elevated cytokine levels are independently predictive of mortality. Cytokine assays (TNF-alpha, IL-6, and IL-10) were performed on admission plasma samples from 172 adult Thai patients with severe melioidosis. Mortality was 31.4%. APACHE II score; septicemia; plasma lactate; TNF-alpha, IL-6, and IL-10 concentrations; and IL-10/TNF-alpha and IL-6/IL-10 ratios were each associated with outcome (P</=.001 for all variables). Only the APACHE II score and either IL-6 or IL-10 concentration were independent predictors of mortality, as determined by use of multiple logistic regression (with cytokine concentrations and ratios entered separately). In a multivariate analysis, including both IL-6 and IL-10, the IL-10 concentration was no longer predictive. Therefore, APACHE II scores and either IL-6 or IL-10 concentration may be the most reliable parameters for stratification of patients in future studies of severe gram-negative sepsis.
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