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An acute gastroenteritis (AGE) outbreak caused by a norovirus occurred at a hospital in Shanghai, China, was studied for molecular epidemiology, host susceptibility and serological roles. Rectal and environmental swabs, paired serum samples and saliva specimens were collected. Pathogens were detected by real-time polymerase chain reaction and DNA sequencing. Histo-blood group antigens (HBGA) phenotypes of saliva samples and their binding to norovirus protruding proteins were determined by enzyme-linked immunosorbent assay. The HBGA-binding interfaces and the surrounding region were analysed by the MegAlign program of DNAstar 7.1. Twenty-seven individuals in two care units were attacked with AGE at attack rates of 9.02 and 11.68%. Eighteen (78.2%) symptomatic and five (38.4%) asymptomatic individuals were GII.6/b norovirus positive. Saliva-based HBGA phenotyping showed that all symptomatic and asymptomatic cases belonged to A, B, AB or O secretors. Only four (16.7%) out of the 24 tested serum samples showed low blockade activity against HBGA-norovirus binding at the acute phase, whereas 11 (45.8%) samples at the convalescence stage showed seroconversion of such blockade. Specific blockade antibody in the population played an essential role in this norovirus epidemic. A wide HBGA-binding spectrum of GII.6 supports a need for continuous health attention and surveillance in different settings.
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Infecções por Caliciviridae/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Norovirus/classificação , Adulto , Idoso , Anticorpos Antivirais/sangue , Antígenos de Grupos Sanguíneos , Infecções por Caliciviridae/epidemiologia , China/epidemiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/virologia , Surtos de Doenças , Hospitais , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Norovirus/genética , Filogenia , Ligação ProteicaRESUMO
Amauroderma s.lat. has been defined mainly by the morphological features of non-truncate and double-walled basidiospores with a distinctly ornamented endospore wall. In this work, taxonomic and phylogenetic studies on species of Amauroderma s.lat. are carried out by morphological examination together with ultrastructural observations, and molecular phylogenetic analyses of multiple loci including the internal transcribed spacer regions (ITS), the large subunit of nuclear ribosomal RNA gene (nLSU), the largest subunit of RNA polymerase II (RPB1) and the second largest subunit of RNA polymerase II (RPB2), the translation elongation factor 1-α gene (TEF) and the ß-tubulin gene (TUB). The results demonstrate that species of Ganodermataceae formed ten clades. Species previously placed in Amauroderma s.lat. are divided into four clades: Amauroderma s.str., Foraminispora, Furtadoa and a new genus Sanguinoderma. The classification of Amauroderma s.lat. is thus revised, six new species are described and illustrated, and eight new combinations are proposed. SEM micrographs of basidiospores of Foraminispora and Sanguinoderma are provided, and the importance of SEM in delimitation of taxa in this study is briefly discussed. Keys to species of Amauroderma s.str., Foraminispora, Furtadoa, and Sanguinoderma are also provided.
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Objective: To establish a quantitative assay of serum Golgi protein 73 (GP73) using xMAP technology and evaluate its performance. Methods: Monoclonal antibodies against GP73 were prepared and purified, and antibody pair screening was performed by double-antibody sandwich enzyme-linked immunosorbent assay. The screened antibodies were used to construct a Luminex liquid chip detection system, and the analysis performance of the detection system was evaluated. The serum levels of GP73 were detected in 90 clinical samples from healthy controls and patients with chronic hepatitis B infection (CHB) and hepatocellular carcinoma (HCC). Results: Five anti-GP73 monoclonal antibodies were prepared and purified, and 5 antibody pairs were successfully screened. The Luminex liquid chip detection system of GP73 was successfully constructed using 8F10D1 and 10B9F11 antibody pairs. The analytical performance evaluation showed that the sensitivity of this system was 0.25 ng/ml and the dynamic range was 0.25-100 ng/ml. No cross reactivity was observed. The intra- and inter-assay variation for GP73 was <8% and <11%, respectively. The recovery was 83%-92%. The linear regression equation was y=1.141x+ 6.436 (r(2)=0.998 4, P<0.001). The GP73 concentrations in the serum samples of healthy control, CHB group, and HCC group were 42.8 (38.68, 55.90) ng/ml, 61.49 (43.59, 81) ng/ml, and 122.78 (49.36 liter, 264.55) ng/ml, respectively. The levels of GP73 in HCC group were significantly higher than those in CHB group and healthy controls (P<0.05). Moreover, the levels of GP73 in CHB group were significantly higher than those in healthy controls (P<0.05). Conclusions: A liquid chip detection system of GP73 was successfully constructed. It provides a powerful tool for the clinical application of GP73 in the future.
Assuntos
Carcinoma Hepatocelular/sangue , Hepatite B Crônica/sangue , Ensaios de Triagem em Larga Escala/métodos , Neoplasias Hepáticas/sangue , Proteínas de Membrana/sangue , Ensaio de Imunoadsorção Enzimática , Ensaios de Triagem em Larga Escala/normas , HumanosRESUMO
Phylogenetic and taxonomic studies on the brown-rot fungi Postia and related genera, are carried out. Phylogenies of these fungi are reconstructed with multiple loci DNA sequences including the internal transcribed spacer regions (ITS), the large subunit (nLSU) and the small subunit (nSSU) of nuclear ribosomal RNA gene, the small subunit of mitochondrial rRNA gene (mtSSU), the translation elongation factor 1-α gene (TEF1), the largest subunit of RNA polymerase II (RPB1) and the second subunit of RNA polymerase II (RPB2). Ten distinct clades of Postia s.lat. are recognized. Four new genera, Amaropostia, Calcipostia, Cystidiopostia and Fuscopostia, are established, and nine new species, Amaropostia hainanensis, Cyanosporus fusiformis, C. microporus, C. mongolicus, C. piceicola, C. subhirsutus, C. tricolor, C. ungulatus and Postia sublowei, are identified. Illustrated descriptions of the new genera and species are presented. Identification keys to Postia and related genera, as well as keys to the species of each genus, are provided.
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Objective: Evaluate GII.4 norovirus infection and blocking effects of serum antibodies against HBGAs binding to GII.4 norovirus of population in oyster culture area, provide references for screening of fully human monoclonal antibody. Methods: Using a random survey method to collect blood and saliva samples in oyster culture area, select serum samples from the inland region of Guangdong as control group. Identification of salivary HBGA receptor phenotype and detection of serum antibody levels between two areas by ELISA. A vitro neutralization model was to determine the efficiency of serum antibodies blocking GII.4 norovirus and HBGA receptors binding. Results: The age were (50.68 ± 15.17), (52.52 ± 15.90) and (51.37 ± 13.32) years old of 2015, 2016 in experimental group, and in control group, respectively. Males accounted for 5.9% (70/195), 36.6%(60/164), 40.8% (69/169) (χ(2)=0.93, P=0.334). The mean value of serum antibodies Absorbance value was 2.521±0.05 of 2015 and was 2.583±0.045 of 2016 in oyster culture area, the mean value was 2.249±0.05 in control group, there was a statistical difference among three group (F=13.28, P<0.001). The antibody prevalence in the three groups was 100%. BT50 geometric mean titer (GMT) of oyster culture area in 2015 was 423.1±40.11, culture group was 248.2±25.63, there was a statistical difference (t=3.73, P<0.001). Conclusion: The population in oyster culture area does have more chance of exposure and infection GII.4 norovirus, Serum antibody of blocking ability in oyster culture areas is better than the general population in inland city. Suggesting that the population is more immunity resistant infected GII.4 norovirus.
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Anticorpos Bloqueadores/sangue , Infecções por Caliciviridae/prevenção & controle , Norovirus/imunologia , Receptores Virais/metabolismo , Adulto , Idoso , Animais , Infecções por Caliciviridae/imunologia , Estudos de Casos e Controles , China , Exposição Ambiental/efeitos adversos , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , OstreidaeRESUMO
Wrightoporia accommodates polypores producing finely asperulate and amyloid basidiospores, and causing white rot. Thirty-nine species have been described or transferred to this genus; however, only a few species have been referred to molecular phylogeny. In this study, about 140 worldwide specimens of Wrightoporia s.l. were studied morphologically, and ITS and/or nLSU regions from 37 samples, representing 19 species, were sequenced for phylogenetic analysis. Six clades of Wrightoporia s.l. were recognized. The Wrightoporia s.str. clade includes W. avellanea, W. lenta (the generic type) and W. subavellanea. Three clades segregating from Wrightoporia s.str. were proposed separately as three new genera, namely Larssoniporia gen. nov., Pseudowrightoporia gen. nov. and Wrightoporiopsis gen. nov. Two other clades were named after Amylonotus and Amylosporus. According to phylogenetic and morphological evidence, species previously treated in Wrightoporia were transferred to Amylonotus, Amylosporus and the new genera, or were retained as members of Wrightoporia s.l. because no good solution for these species could be found so far. In addition, one new species in Larssoniporia, three new species in Pseudowrightoporia and two new species in Wrightoporiopsis were described. Identification keys to the six genera and species in Amylonotus, Amylosporus, Larssoniporia, Pseudowrightoporia, Wrightoporia and Wrightoporiopsis are provided, respectively.
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Taxonomic and phylogenetic studies on Datronia were carried out. Phylogeny based on ITS, nLSU and RBP2 regions revealed that Datronia in current sense includes species belonging to three distantly related clades in polypores. The Datronia in a restricted sense is proposed for the clade including the type species D. mollis and D. stereoides. Neodatronia gen. nov. was proposed for two new resupinate species, N. gaoligongensis and N. sinensis. Species of Neodatronia differ from Datronia s.s. by their resupinate basidiomes, moderately to frequently branched skeletal hyphae in subiculum. Datroniella gen. nov., typified by D. scutellata was proposed for species in the other clade. Four new species of Datroniella, D. melanocarpa, D. subtropica, D. tibetica and D. tropica, were identified. Species of Datroniella differ from Datronia s.s. by their moderately to frequently branched skeletal hyphae in context and absence of dendrohyphidia. While, differentiate from Neodatronia by their small pileate, effused-reflexed or rarely resupinate basidiomes and absence of dendrohyphidia. Illustrated descriptions of the new species and two new genera are provided. The main morphological differences between Datronia, Datroniella, Neodatronia and related genera are discussed, identification keys to related genera and species in each genus are provided.
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Peach,Prunus persica (L.) Batsch, is widely cultivated in gardens and plantations in northern China. During the summer of 2002, a severe sapwood rot of 5-year-old saplings was observed in a commercial nursery near Tieling, Liaoning Province, northeast China, 42°24'N, 123°55'E. More than 80% of saplings were infected and 35% were dead. Leaves were chlorotic or necrotic and dry, and wood discoloration and white sapwood rot were observed in cross sections of infected trees. Basidiocarps on the diseased trees were identified as Schizophyllum commune Fr.:Fr. (2); on potato dextrose agar (PDA), isolates obtained from decayed wood yielded colonies characteristic of S. commune as well (3). Basidiocarps had been initiated in early June and sometimes fruited over the entire length of the stem and some parts of major branches. Liaoning Province had an abnormally cold winter in 2001 and freeze injury may have predisposed the saplings to S. commune. In addition to P. persica, P. pseudocerasus Lindl. and P. salicina Lindl. were symptomatic. Pathogenicity was confirmed by inoculation of healthy saplings of peach in the greenhouse. Saplings were subjected to freezing for 1 week and 15 were inoculated with S. commune and five were inoculated with agar. Mycelial plugs, grown for 9 days on PDA, were the inoculum for stem wounds. The inoculated area was then covered by wet cotton and wrapped in Parafilm for 2 weeks. Symptoms developed on 14 of 15 inoculated saplings after 6 weeks. Symptoms progressed from chlorotic leaves to decayed bark and wood. After 10 weeks, 11 saplings were dead. The pathogen was reisolated from 13 of 14 symptomatic saplings, and fruiting bodies of S. commune developed on eight saplings. Control saplings remained symptomless. In China and the United States, S. commune is widely reported as a saprotroph or opportunistic pathogen of many woody angiosperms (4) and some gymnosperms (1). To our knowledge, this is the first report of S. commune causing sapwood rot of P. persica in China. References: (1) D. F. Farr et al. Fungal Databases, Systematic Botany and Mycology Laboratory. On-line publication. ARS, USDA, 2005. (2) J. P. Lindsey et al. Bibl. Mycol. 63:1, 1978. (3) M. K. Nobles. Can. J. Res. Sect. C Bot. Sci. 26:281, 1948. (4) F. L. Tai. Sylloge Fungorum Sinicorum. Science Press, Beijing, 1979.
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Members of the Phellinus weirii complex cause laminated root rot of living conifers. The cedar type (P. weirii (Murrill) Gilb. sensu stricto) of the complex is usually found on species of the Cupressaceae family, especially Thuja plicata in western North America, and the Douglas-fir type (P. sulphurascens Pilát) is found on species of the Pinaceae family (1,2,3). Outside North America, P. weirii occurs on species of Juniperus in the Ural Mountains, and P. sulphurascens occurs on other conifers in eastern Asia, including China (1). During a field inventory of wood-decay fungi in western China in 2003, laminated root rot of Sabina przewalskii (synonym Juniperus przewalskii) was found in natural forests of the Qilian Mountains in Qinghai Province (37°36'N and 102°15'E). Trees were approximately 80 to 150 years old and occurred in pure stands. Distinct disease patches that were as much as one hectare consisted of dead-standing and symptomatic trees, suggesting that the fungus spread by root contact. Symptomatic trees showed slow growth, thin crowns, and chlorotic foliage. After cutting several of the symptomatic trees, cambial necrosis and wood decay were found, and the trees apparently died when the cambial necrosis girdled the base of the trees. The wood of infected trees was reddish brown at the early stages of decay and later had numerous small cavities and separated into sheets at the junction of annual rings. Perennial, poroid, resupinate, dark brown basidiocarps formed on the root surface of dead trees. The basidiocarps had a monomitic hyphal system, hyphae without clamp connections, trama tissue with hyphoid setae, and thin-walled, hyaline, smooth, ellipsoid basidiospores. The fungus was identified as P. weirii and distinguished from P. sulphurascens by its perennial basidiocarps, smaller pores (5 to 8 versus 4 to 5 per mm), and narrower hyphoid setae (4 to 6 versus 5 to 10 µm in diameter). P. weirii also resembles P. ferrugineofuscus (P. Karst.) Bourdot in macro-morphology, but the latter species is a saprophyte and has allantoid to almost lunate basidiospores. The studied specimens of P. weirii and P. sulphurascens are preserved at the herbaria of the Botanical Museum of the University of Helsinki, the Institute of Applied Ecology, and the Chinese Academy of Sciences as DAOM 8734, Lowe 6960, TAA 52744, 55644, and 103812, and Dai 988, 2053, 2061, 2527, and 5067. To my knowledge, this is the first report of P. weirii sensu stricto from China and the first report of laminated root rot on S. przewalskii. References: (1) Y. C. Dai and G. F. Qin. Fungal Sci. 13:101, 1998. (2) E. M. Hansen et al. Species limits for Phellinus weirii. Pages 119-127 in: Root and butt rots of forest tress. Int. Conf. Root and Butt Rots, INRA, France, 1998. (3) M. J. Larsen et al. Mycologia 86:121, 1994.
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Members of the Heterobasidion annosum (Fr.) Bref. complex are among the most important pathogens in coniferous forests of Europe and North America. Three intersterile groups (P, S, and F) have been found in this complex from Europe (1) and were recently segregated into three species based on intersterility, host preferences, and morphology (4). In a survey of wood-rotting fungi in China in 2002, Heterobasidion spp. were found on Tsuga chinensis (Franch.) Pritz and T. dumosa (D. Don) Eichl. in natural forests from the northern Sichuan Province of southwestern China (32°43' to 33°11' N, 103°50' to 103°53' E.). Basidiocarps of the fungus were relatively common on decayed wood in roots of dead trees, stumps, and fallen trunks. We collected four basidiocarps (Dai 4045, 4051, 4214, and 4224 in the Institute of Applied Ecology, Chinese Academy of Sciences, IFP) from three stands of mixed coniferous forests and made 40 homokaryotic, single-basidiospore cultures (02046, 02047, 02050, and 02051 in the Finnish Forest Research Institute). Two homokaryons from each basidiocarp were paired with homokaryotic tester strains of European H. annosum (P group), H. parviporum Niemelä & Korhonen (S group), and H. abietinum Niemelä & Korhonen (F group). The pairings showed that the progeny from the four basidiocarps are H. parviporum. The Chinese isolates did not form clamp connections with H. annosum sensu stricto, and a strong demarcation line developed in all these pairings. In contrast, the Chinese isolates formed clamp connections in almost every pairing with European H. parviporum, the clamp connections developed in both sides of the pairings, and no distinct demarcation line was present in most of these pairings. The Chinese homokaryons were also compatible with European H. abietinum, but in most of these pairings, clamp connections were found in the isolate from China but not in the European tester, and a demarcation line was present in most of the pairings. In contrast to H. annosum sensu stricto, the Chinese basidiocarps had smaller pores (4.5 to 6 per mm versus 3 to 4.5 per mm), and a thin tomentum on the pileal surface in contrast to the basidiocarps of H. abietinum. Previously, H. parviporum was found in Asia on coniferous hosts such as Abies, Larix, Picea and Pinus spp. (2). The North American S group of H. annosum sensu lato attacks species of Tsuga spp. in western North America (3), but to our knowledge, this is the first report of H. parviporum on native species of Tsuga spp. outside North America. References: (1) P. Capretti et al. Eur. J. For. Pathol. 20:231, 1990. (2) Y. C. Dai and K. Korhonen. Eur. J. For. Pathol. 29:273, 1999. (3) G. M. Filip and D. J. Morrison. North America. Pages 405-427 in: Heterobasidion annosum. Biology, Ecology, Impact and Control. CAB International, Wallingford, UK, 1998. (4) T. Niemelä and K. Korhonen. Taxonomy of the genus Heterobasidion. Pages 27-33 in: Heterobasidion annosum. Biology, Ecology, Impact and Control. CAB International, Wallingford, UK, 1998.
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Substâncias de Crescimento/farmacologia , Linfoma de Células B/patologia , Antígenos de Superfície/análise , Medula Óssea/patologia , Divisão Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Meios de Cultura Livres de Soro , Técnicas de Cultura/métodos , Galactose Oxidase/farmacologia , Humanos , Linfoma de Células B/sangue , Linfoma de Células B/líquido cefalorraquidiano , Monócitos/patologia , Receptores de Antígenos de Linfócitos B/análise , Proteínas Recombinantes/farmacologia , Células Tumorais CultivadasAssuntos
Sistema Cardiovascular/efeitos dos fármacos , Plantas Medicinais , Valeriana/análise , Animais , Pressão Sanguínea/efeitos dos fármacos , Gatos , China , Circulação Coronária/efeitos dos fármacos , Feminino , Técnicas In Vitro , Masculino , Contração Miocárdica/efeitos dos fármacos , Extratos Vegetais/farmacologia , CoelhosRESUMO
A semisolid culture system for B-cell colony formation is described. The system includes pretreatment of B-cells by neuraminidase-galactose oxidase and help of mitomycin-treated T-cells. With this assay system, colony-forming B-cell precursors were detected in all eight patients we studied with B-cell chronic lymphocytic leukemia. These patients' own T-cell helper effect was less than that of normal T-cells.
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Linfócitos B/citologia , Leucemia Linfoide/sangue , Idoso , Linfócitos B/imunologia , Células Cultivadas , Feminino , Humanos , Ativação Linfocitária , Masculino , Pessoa de Meia-IdadeRESUMO
Primary ovarian fibrosarcoma is an exceedingly rare malignant ovarian stromal tumor which has a poor prognosis. We report here a 46-year-old woman who suffered from irregular vaginal bleeding for 2 months. She received hysterectomy and salpingo-oophorectomy due to a provisional diagnosis of uterine and ovarian tumors. At surgery, an 8-cm ovarian solid multilobular tumor was found. Frozen section examination revealed an ovarian fibrosarcoma. She then underwent staging procedures including intraperitoneal washing, cytology, and pelvic and para-aortic lymph node sampling. Final pathologic examination revealed that the tumor exhibited densely packed spindle cells in storiform configuration with obvious increased mitotic activity. In addition, the flow cytometric study showed marked elevated percentage of tumor cells in the S phase (13.1%). After surgery, the patient received six courses of combination chemotherapy with epirubicin, ifosfamide, and dacarbazine (DTIC). The patient stood the treatment well and is free from disease 6 years later.
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Fibrossarcoma/diagnóstico , Neoplasias Ovarianas/diagnóstico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Diagnóstico Diferencial , Feminino , Fibrossarcoma/tratamento farmacológico , Fibrossarcoma/patologia , Fibrossarcoma/cirurgia , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Sobreviventes , Hemorragia Uterina/etiologiaRESUMO
This paper describes a culture system which supports the formation of B cell and some T cell colonies under serum-free conditions in peripheral blood samples of normal individuals and patients with chronic lymphocytic leukemia (CLL) of B cell type. In this system, serum is replaced by bovine serum albumin, transferrin, cholesterol, insulin and catalase or horseradish peroxidase. In addition, it is necessary to add staphylococcus protein A, mitomycin-treated T cells as feeders and phytohemagglutinin leukocyte-conditioned medium as a source of growth factors. The plating efficiency is greatly enhanced when normal cells are incubated with galactose oxidase prior to plating and when CLL cells are exposed sequentially to neuraminidase and galactose oxidase.
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Linfócitos B/citologia , Leucemia Linfoide/sangue , Células Cultivadas , Meios de Cultura , Técnicas de Cultura/métodos , Humanos , Mitomicina , Mitomicinas/farmacologia , Valores de Referência , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacosRESUMO
Frequent loss of heterozygosity of microsatellites markers on specific chromosomal region have been reported in various types of primary human cancer. The same loss of heterozygosity has also been identified in the matched plasma/serum DNA. Using 109 microsatellite markers representing 24 chromosomal arms, we have examined the loss of heterozygosity in 21 cases of hepatocellular carcinoma, six of cholangiocarcinoma, and 27 cases of chronic hepatitis or cirrhosis. All cases of the hepatocellular carcinoma showed deletion from two to 10 chromosomal arms, while deletion of chromosomes from two to eight regions was detected in five of six cholangiocarcinoma patients. One or more loss of heterozygosity in the paired serum DNA could be detected in 16 of 25 (76.2%) hepatocellular carcinoma patients. In contrast, no alterations in serum DNA test could be found in cholangiocarcinoma patients. Five of seven (71.4%) hepatocellular carcinoma patients with alpha-fetoprotein levels less than 20 ng ml(-1) produced positive serum DNA test. The profiles of 19 microsatellite markers gave a 100% positive predictive value and an 80.8% negative predictive value for hepatocellular carcinoma. In conclusion, we have determined a profile of microsatellite markers appropriate for differential diagnosis of primary liver cancer. The discovery may permit a high-throughput screening of hepatocellular carcinoma at an early stage of disease.
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Alelos , Neoplasias dos Ductos Biliares/genética , Carcinoma Hepatocelular/genética , Colangiocarcinoma/genética , DNA de Neoplasias/sangue , DNA Satélite/sangue , Neoplasias Hepáticas/genética , Adulto , Idoso , Feminino , Deleção de Genes , Hepatite Crônica/genética , Humanos , Cirrose Hepática/genética , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase , Prognóstico , alfa-Fetoproteínas/metabolismoRESUMO
BACKGROUND: The CLOtest is based on the production of ammonia from urea in the presence of urease. In theory, substrate that has not been consumed in a negative test can be reused. METHODS: We collected negative CLOtest pellets after their first use and stored them at room temperature. Whenever a CLOtest was needed during endoscopy, two biopsy specimens were taken from the antrum. One specimen was tested with a new CLOtest and the other with one that had been used previously. Time to color change was observed in paired tests. RESULTS: We used 216 previously used CLOtest pellets with biopsy specimens obtained from 317 patients. Of the paired tests, 204 matched positive and 108 tested negative. Only 5 paired tests had discrepant results. Three had positive results only with a new CLOtest, and 2 were positive only with the reused test. In positive paired tests, there was significant linear correlation in log-transformed color change time between reused and new tests (p < 0.001). Ninety-two percent of previously used pellets were reused fewer than three times before they yielded a positive color change; the interval to this occurrence ranged from 2 to 15 days. Compared with the new CLOtest, the sensitivity of the reused CLOtest was 98. 6% and the specificity was 98.2%. CONCLUSIONS: A negative CLOtest kept at room temperature can be reused within a short period of time, in circumstances in which there are environmental and economic considerations to be taken into account.