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1.
Mar Pollut Bull ; 201: 116267, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38522334

RESUMO

Weather radiosondes play a crucial role in gathering atmospheric data for weather modeling and forecasting. However, their impact on marine wildlife, particularly seabirds, has raised concerns regarding the potential threats posed by these instruments. This study aims to assess the adverse effects of weather balloons on albatrosses, with a focus on the Southwest Atlantic region. The research reveals seven cases of entanglement of radiosonde equipment, leading to severe injuries and mortality along the Southern and Southeastern coasts of Brazil. Recommendations for mitigating the environmental impact of weather balloons include the adoption of biodegradable materials in their design and the implementation of improved retrieval protocols. Furthermore, the study stresses the importance of continued monitoring and research to address the interaction of weather radiosondes with marine animals. This approach is vital for ensuring the sustainable collection of scientific data while minimizing harm to marine life and ecosystems.


Assuntos
Aves , Ecossistema , Animais , Brasil , Tempo (Meteorologia) , Animais Selvagens , Monitoramento Ambiental
2.
AJNR Am J Neuroradiol ; 43(11): 1639-1645, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36202554

RESUMO

BACKGROUND AND PURPOSE: MR imaging can reflect the pathologic progression of carcinoma ex pleomorphic adenoma (CXPA). This study aimed to identify the imaging findings related to extracapsular invasion of CXPA. Additionally, the pathologic background of these findings was investigated. MATERIALS AND METHODS: This retrospective study included 37 patients with histologically confirmed CXPA. Three radiologists independently evaluated whether the CXPA showed the following characteristic MR imaging findings: border, capsule, the corona sign on fat-saturated T2WI and contrast-enhanced fat-saturated T1WI, and the black ring sign. The corona sign appeared larger on fat-saturated and/or contrast-enhanced fat-saturated T1WI than on T1WI. The black ring sign was defined as an intratumoral nodule with a thick low-intensity rim on T2WI. Interreader agreement of the visual assessment was performed using κ analysis, and MR imaging and histopathologic findings were also correlated. Kaplan-Meier survival and the log-rank test were used to estimate the 3-year disease-free survival. RESULTS: MR imaging findings, especially peritumoral findings, showed a significant difference between invasive and noninvasive CXPA. The reliability was poor for the border and capsule. In contrast, it was good for the corona sign on fat-saturated and contrast-enhanced fat-saturated T1WI and the black ring sign. Pathologically, the corona sign reflected the invasiveness of the tumor and inflammatory cells, while the black ring sign reflected hyalinization or fibrosis. The corona sign also showed a significant difference in the 3-year disease-free survival. CONCLUSIONS: MR imaging findings, including the corona and black ring signs, reliably differentiated invasive and noninvasive CXPA. The corona sign can be used as a prognostic factor for CXPA.


Assuntos
Adenoma Pleomorfo , Carcinoma , Neoplasias das Glândulas Salivares , Humanos , Adenoma Pleomorfo/diagnóstico por imagem , Neoplasias das Glândulas Salivares/diagnóstico por imagem , Neoplasias das Glândulas Salivares/patologia , Estudos Retrospectivos , Reprodutibilidade dos Testes , Prognóstico , Imageamento por Ressonância Magnética , Carcinoma/diagnóstico por imagem
3.
Nat Commun ; 11(1): 4619, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934234

RESUMO

The Weyl semimetal (WSM), which hosts pairs of Weyl points and accompanying Berry curvature in momentum space near Fermi level, is expected to exhibit novel electromagnetic phenomena. Although the large optical/electronic responses such as nonlinear optical effects and intrinsic anomalous Hall effect (AHE) have recently been demonstrated indeed, the conclusive evidence for their topological origins has remained elusive. Here, we report the gigantic magneto-optical (MO) response arising from the topological electronic structure with intense Berry curvature in magnetic WSM Co3Sn2S2. The low-energy MO spectroscopy and the first-principles calculation reveal that the interband transitions on the nodal rings connected to the Weyl points show the resonance of the optical Hall conductivity and give rise to the giant intrinsic AHE in dc limit. The terahertz Faraday and infrared Kerr rotations are found to be remarkably enhanced by these resonances with topological electronic structures, demonstrating the novel low-energy optical response inherent to the magnetic WSM.

4.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-789780

RESUMO

@#BACKGROUND: Few studies have examined the association of layperson characteristics with cardiopulmonary resuscitation (CPR) provision. Previous studies suggested provider characteristics, including age and gender, were associated with CPR quality, particularly chest compression (CC) depth. We sought to determine the association of subject characteristics, including age and gender with layperson CPR quality during an unannounced simulated CPR event. We hypothesized shallower CC depth in females, and older-aged subjects. METHODS: As part of a larger multicenter randomized controlled trial of CPR training for cardiac patients' caregivers, CPR skills were assessed 6 months after training. We analyzed associations between subject characteristics and CC rate, CC depth and no-flow time. Each variable was analyzed independently; significant predictors determined via univariate analysis were assessed in a multivariate regression model. RESULTS: A total of 521 laypersons completed a 6-month CPR skills assessment and were included in the analysis. Mean age was 51.8±13.7 years, 75% were female, 57% were Caucasian. Overall, mean CC rate was 88.5±25.0 per minute, CC depth was 50.9±2.0 mm, and mean no-flow time was 15.9±2.7 sec/min. CC depth decreased significantly in subjects >62 years (P<0.001). Male subjects performed deeper CCs than female subjects (47.5±1.7 vs. 41.9±0.6, P<0.001). CONCLUSION: We found that layperson age >62 years and female gender are associated with shallower CC depth.

6.
J Fish Dis ; 35(7): 471-80, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22536999

RESUMO

We developed a simple genotyping method for Flavobacterium psychrophilum for analysing two single nucleotide polymorphisms (SNPs) in the gyrA gene and to distinguish between isolates that are virulent and avirulent to ayu, Plecoglossus altivelis altivelis (Temminck & Schlegel). The genotyping method is an on/off switch assay and is based on the polymerase chain reaction technique with phosphorothioated primers. We classified 232 isolates from four families of fish (i.e. Plecoglossidae, Osmeridae, Cyprinidae and Salmonidae) into four genotypes (G-C, A-T, A-C and G-T). The G-C type isolates exhibited strong pathogenicity to ayu, whereas the A-T and G-T types did not show any pathogenicity to this species. The A-C type exhibited no or weak pathogenicity to ayu. These results indicate that genotyping F. psychrophilum isolates with two SNPs from gyrA can clearly distinguish between isolates potentially harmful to ayu (G-C type) and those that are potentially not harmful or less harmful (A-C, A-T and G-T type). The on/off switch assay provides a quick, simple, and very powerful DNA genotyping technique for F. psychrophilum isolates.


Assuntos
Doenças dos Peixes/microbiologia , Infecções por Flavobacteriaceae/veterinária , Flavobacterium/genética , Flavobacterium/patogenicidade , Técnicas de Genotipagem/veterinária , Osmeriformes , Animais , Sequência de Bases , DNA Girase/genética , Doenças dos Peixes/mortalidade , Infecções por Flavobacteriaceae/microbiologia , Infecções por Flavobacteriaceae/mortalidade , Flavobacterium/classificação , Japão , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Análise de Sobrevida , Virulência/genética
7.
Oncogene ; 31(13): 1623-35, 2012 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-21860426

RESUMO

The tyrosine kinase c-Src is upregulated in various human cancers; however, the molecular mechanisms underlying c-Src-mediated tumor progression remain unclear. Here we show that downregulation of microRNA (miR)-542-3p is tightly associated with tumor progression via c-Src-related oncogenic pathways. In c-Src-transformed fibroblasts and human cancer cells that overexpress c-Src, miR-542-3p is substantially downregulated, and the ectopic expression of miR-542-3p suppresses tumor growth. We identified the integrin-linked kinase (ILK) as a conserved target of miR-542-3p. ILK upregulation promotes cell adhesion and invasion by activating the integrin-focal adhesion kinase (FAK)/c-Src pathway, and can also contribute to tumor growth via the AKT and glycogen synthase kinase 3ß pathways. MiR-542-3p expression is downregulated by the activation of c-Src-related signaling molecules, including epidermal growth factor receptor, K-Ras and Ras/Raf/mitogen-activated protein kinase/extracellular signal-regulated kinase. In human colon cancer tissues, downregulation of miR-542-3p is significantly correlated with the upregulation of c-Src and ILK. Our results suggest that the novel c-Src-miR-542-3p-ILK-FAK circuit plays a crucial role in controlling tumor progression.


Assuntos
MicroRNAs/metabolismo , Neoplasias/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Animais , Proteína Tirosina Quinase CSK , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Neoplasias do Colo/genética , Progressão da Doença , Quinase 1 de Adesão Focal/metabolismo , Humanos , Camundongos , Invasividade Neoplásica/genética , Neoplasias/metabolismo , Regulação para Cima , Quinases da Família src
8.
Oncogene ; 30(32): 3489-501, 2011 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-21383697

RESUMO

The tyrosine kinase c-Src is upregulated in various human cancers, but the molecular mechanisms underlying c-Src-mediated tumor growth remain unclear. Here we examined the involvement of microRNAs in the c-Src-mediated tumor growth. Microarray profiling revealed that c-Src activation downregulates a limited set of microRNAs, including miR-99a, which targets oncogenic mammalian target of rapamycin (mTOR) and fibroblast growth factor receptor 3 (FGFR3). Re-expression of miR-99a suppressed tumor growth of c-Src-transformed cells, and this effect was restored by the overexpression of mTOR. The downregulation of miR-99a was also observed in epidermal growth factor- and Ras-transformed cells, and it was suppressed by inhibiting the mitogen-activated protein kinase (MAPK) pathway. Furthermore, miR-99a downregulation is associated with mTOR/FGFR3 upregulation in various human lung cancer cells/tissues. The tumorigenicity of these cells was suppressed by the introduction of miR-99a. These findings suggest that the miR-99a-mTOR/FGFR3 pathway is crucial for controlling tumor growth in a wide range of human cancers that harbor upregulation of the Src-related oncogenic pathways.


Assuntos
MicroRNAs/genética , Neoplasias/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Serina-Treonina Quinases TOR/genética , Quinases da Família src/genética , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Células Cultivadas , Análise por Conglomerados , Regulação para Baixo , Perfilação da Expressão Gênica , Células HEK293 , Humanos , Immunoblotting , Imuno-Histoquímica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/metabolismo , Neoplasias/patologia , Pirimidinas/farmacologia , Interferência de RNA , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/metabolismo , Quinases da Família src/metabolismo
9.
Eat Weight Disord ; 15(4): e270-4, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21406951

RESUMO

During a four month scholarly leave in United States of America, researchers designed a culturally appropriate prevention program for eating disorders (ED) for Brazilian adolescent girls. The program "Se Liga na Nutrição" was modeled on other effective programs identified in a research literature review and was carried out over eleven interactive sessions. It was positively received by the adolescents who suggested that it be part of school curricula. The girls reported that it helped them to develop critical thinking skills with regards to sociocultural norms about body image, food and eating practices.


Assuntos
Imagem Corporal , Comportamento Alimentar/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/prevenção & controle , Avaliação de Programas e Projetos de Saúde , Adolescente , Brasil , Criança , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Humanos , Masculino , Projetos Piloto , Serviços de Saúde Escolar
11.
Histopathology ; 52(6): 731-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18397280

RESUMO

AIMS: Diffuse large B-cell lymphoma (DLBCL) usually proliferates effacing lymph follicles. In occasional cases, tumour cells show an interfollicular pattern of proliferation preserving lymph follicles. The aim was to analyse clinicopathological findings in DLBCL showing an interfollicular pattern of proliferation to determine whether this type of lymphoma is a distinct entity of DLBCL. METHODS AND RESULTS: Clinicopathological findings in 12 cases of DLBCL showing an interfollicular pattern of proliferation [interfollicular group (IF)] were examined and compared with those in 30 cases of DLBCL with ordinary morphology [control group (CG)]. IF showed a significantly lower lactate dehydrogenase level and International Prognostic Index scores than CG (P = 0.023 and P < 0.01, respectively). The frequency of localized disease, clinical stage 1 and 2, in IF was higher than that in CG (P = 0.016). A morphologically polymorphous pattern of proliferation was found in seven of 12 cases (58.3%) in IF, which was higher than that in CG, five (16.7%) of 30 cases (P < 0.01). Clonality analysis with the polymerase chain reaction method revealed that all 11 IF cases examined showed a monoclonal pattern. Immunohistochemically, the majority (11 of 12) of IF cases showed a non-germinal centre B-cell phenotype and the frequency was higher than that in CG (P = 0.021). CONCLUSION: Diffuse large B-cell lymphoma with an interfollicular pattern of proliferation shows distinct clinical and pathological findings from ordinary DLBCL.


Assuntos
Linfoma Difuso de Grandes Células B/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Proliferação de Células , Feminino , Centro Germinativo/citologia , Humanos , Imuno-Histoquímica , Japão , L-Lactato Desidrogenase/metabolismo , Linfoma Difuso de Grandes Células B/diagnóstico , Masculino , Pessoa de Meia-Idade , Fenótipo , Prognóstico
13.
Br J Cancer ; 96(6): 986-92, 2007 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-17325702

RESUMO

Recent studies have identified vimentin, a type III intermediate filament, among genes differentially expressed in tumours with more invasive features, suggesting an association between vimentin and tumour progression. The aim of this study, was to investigate whether vimentin expression in colon cancer tissue is of clinical relevance. We performed immunostaining in 142 colorectal cancer (CRC) samples and quantified the amount of vimentin expression using computer-assisted image analysis. Vimentin expression in the tumour stroma of CRC was associated with shorter survival. Overall survival in the high vimentin expression group was 71.2% compared with 90.4% in the low-expression group (P=0.002), whereas disease-free survival for the high-expression group was 62.7% compared with 86.7% for the low-expression group (P=0.001). Furthermore, the prognostic power of vimentin for disease recurrence was maintained in both stage II and III CRC. Multivariate analysis suggested that vimentin was a better prognostic indicator for disease recurrence (risk ratio=3.5) than the widely used lymph node status (risk ratio=2.2). Vimentin expression in the tumour stroma may reflect a higher malignant potential of the tumour and may be a useful predictive marker for disease recurrence in CRC patients.


Assuntos
Neoplasias Colorretais/metabolismo , Vimentina/biossíntese , Idoso , Neoplasias Colorretais/patologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Células Estromais/metabolismo , Células Estromais/patologia
14.
Leukemia ; 20(9): 1551-6, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16926850

RESUMO

CDCP1, a novel stem cell marker, is expressed in hematopoietic cell line K562 but not in Jurkat. When CDCP1 promoter was transfected exogenously, Jurkat showed comparable promoter activity with K562, suggesting that the factor to enhance transcription was present but interfered to function in Jurkat. The reporter assay and si-RNA-mediated knockdown experiment revealed that zfp67, a zinc-finger protein, enhanced CDCP1 transcription. Amount of zfp67 in Jurkat was comparable with K562, but chromatin immunoprecipitation showed that zfp67 bound to CDCP1 promoter in K562 but not in Jurkat. There are CpG sequences around the promoter of CDCP1, which were heavily methylated in Jurkat but not in K562. Addition of demethylating reagent to Jurkat induced CDCP1 expression, and increased the zfp67 binding to CDCP1 promoter. Among normal hematopoietic cells such as CD34+CD38- cells, lymphocytes and granulocytes, inverse correlation between proportion of methylated CpG sequences and CDCP1 expression level was found. Demethylation of CpG sequences in lymphocytes, in which CpG sequences were heavily methylated, induced CDCP1 expression and its expression level further increased through zfp67 overexpression. The methylation of DNA appeared to regulate the cell-type-specific expression of CDCP1 through the control of interaction between chromatin DNA and transcription factors.


Assuntos
Antígenos CD/metabolismo , Moléculas de Adesão Celular/metabolismo , Metilação de DNA , Células-Tronco Hematopoéticas/metabolismo , Proteínas de Neoplasias/metabolismo , Antígenos CD/genética , Antígenos de Neoplasias , Sequência de Bases , Biomarcadores/metabolismo , Moléculas de Adesão Celular/genética , Imunoprecipitação da Cromatina , Ilhas de CpG , Primers do DNA , Humanos , Células Jurkat , Células K562 , Proteínas de Neoplasias/genética , Regiões Promotoras Genéticas , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Ultrasonics ; 44 Suppl 1: e101-4, 2006 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-16860361

RESUMO

The near infrared (NIR) absorption was investigated on the glucose aqueous solutions with various optical pathlengths (PLs) and processed by ultrasonic cavitation. In water, the strong absorption peak at a wavelength of 1430 nm, appeared in the case of short PL, was separated into several peaks in the case of wide PL due to increasing the number of H(2)O clusters. In a d(+) glucose solution, it was seen that NIR absorption was reduced at peculiar wavelengths of 970 nm and 1130 nm and its profile changed in a capricious manner in the region from 1300 nm to 1600 nm. The cavitation generated lots of OH(-) ion in water and made the capricious absorption profile regularly graded with the cavitation time toward less-absorptive direction. These effects are supposed to be caused by the dipole moments of H(2)O clusters arranged by the interaction between them and generated basic OH ions. The statistical principal component regression (PCR) and partial least-squares (PLS) regression demonstrated that the treatment of UC was helpful to enhance the glucose sensitivity.


Assuntos
Glucose/análise , Sonicação , Espectrofotometria Infravermelho/métodos , Água/química , Algoritmos , Interpretação Estatística de Dados , Glucose/efeitos da radiação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Soluções
16.
J Pathol ; 210(1): 75-84, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16823897

RESUMO

CDCP1 is a novel stem cell marker that is expressed in several types of cancer. The mechanisms by which CDCP1 expression is regulated, and the clinical implications of this marker, have not been clarified. In this report, we examine the epigenetic regulation of CDCP1 expression in cell lines and clinical samples from patients with breast cancer. Many CpG sequences were localized around the transcription initiation site of CDCP1. These CpG motifs were found to be poorly methylated in cell lines with high levels of CDCP1 expression and heavily methylated in cell lines with low levels of CDCP1 expression. The in vitro methylation of CpG sites decreased CDCP1 promoter activity, and the addition of a demethylating reagent restored activity. In 25 breast cancer samples, an inverse correlation was noted between the CDCP1 expression level and the proportion of methylated to non-methylated CpG sites. Tumours with high-level CDCP1 expression showed higher levels of proliferation, as revealed by immunohistochemical detection of the MIB-1 antigen, than tumours with low-level CDCP1 expression. These findings indicate that the expression of CDCP1 is regulated by methylation of its promoter region in tumours. CDCP1 expression may prove to be useful in the further characterization of cancers.


Assuntos
Antígenos CD/genética , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Moléculas de Adesão Celular/genética , Epigênese Genética/genética , Regulação Neoplásica da Expressão Gênica/genética , Proteínas de Neoplasias/genética , Adenocarcinoma/genética , Antígenos CD/análise , Antígenos de Neoplasias/genética , Biomarcadores Tumorais/análise , Moléculas de Adesão Celular/análise , Linhagem Celular Tumoral , Ilhas de CpG/genética , Feminino , Humanos , Imuno-Histoquímica/métodos , Antígeno Ki-67/genética , Leucemia/genética , Linfoma/genética , Metilação , Proteínas de Neoplasias/análise , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Transcrição Gênica/genética
17.
J Appl Microbiol ; 95(3): 563-75, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12911705

RESUMO

AIMS: To comparatively evaluate the adaptive stationary-phase acid tolerance response (ATR) in food-borne pathogens induced by culturing in glucose-containing media, as affected by strain variability and antibiotic resistance, growth temperature, challenge pH and type of acidulant. METHODS AND RESULTS: Antibiotic resistant or sensitive strains of Listeria monocytogenes, Salmonella including S. Typhimurium DT104, and Escherichia coli O157:H7 were cultured (30 degrees C for 24 h; 10 degrees C for up to 14 days) in trypticase soya broth with yeast extract (TSBYE) with 1% or without glucose to induce or prevent acid adaptation, respectively. Cultures were subsequently exposed to pH 3.5 or 3.7 with lactic or acetic acid at 25 degrees C for 120 min. Acid-adapted cultures were more acid tolerant than nonadapted cultures, particularly those of L. monocytogenes and Salmonella. No consistent, positive or negative, influence of antibiotic resistance on the pH-inducible ATR or acid resistance (AR) was observed. Compared with 30 degrees C cultures, growth and acid adaptation of L. monocytogenes and S. Typhimurium DT104 at 10 degrees C markedly reduced their ATR and AR in stationary phase. E. coli O157:H7 had the greatest AR, relying less on acid adaptation. A 0.2 unit difference in challenge pH (3.5-3.7) caused great variations in survival of acid-adapted and nonadapted cells. CONCLUSIONS: Culturing L. monocytogenes and Salmonella to stationary phase in media with 1% glucose induces a pH-dependent ATR and enhances their survival to organic acids; thus, this method is suitable for producing acid-adapted cultures for use in food challenge studies. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacterial pathogens may become acid-adapted in foods containing glucose or other fermentable carbohydrates. Low storage temperatures may substantially decrease the stationary-phase ATR of L. monocytogenes and S. Typhimurium DT104, but their effect on ATR of E. coli O157:H7 appears to be far less dramatic.


Assuntos
Glucose/farmacologia , Listeria monocytogenes/crescimento & desenvolvimento , Salmonella typhimurium/crescimento & desenvolvimento , Ácido Acético/farmacologia , Adaptação Fisiológica , Animais , Contagem de Colônia Microbiana , Meios de Cultura , Resistência a Medicamentos/fisiologia , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/crescimento & desenvolvimento , Microbiologia de Alimentos , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Salmonella typhimurium/efeitos dos fármacos
18.
J Food Prot ; 66(6): 985-92, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12800998

RESUMO

The objective of this study was to evaluate the survival and growth of acid-adapted and nonadapted Listeria monocytogenes inoculated onto fresh beef subsequently treated with acid or nonacid solutions. Beef slices (2.5 by 5 by 1 cm) from top rounds were inoculated with acid-adapted or nonadapted L. monocytogenes (4.6 to 5.0 log CFU/cm2) and either left untreated (control) or dipped for 30 s in water at 55 degrees C, water at 75 degrees C, 2% lactic acid at 55 degrees C, or 2% acetic acid at 55 degrees C. The beef slices were vacuum packaged and stored at 4 or 10 degrees C and were analyzed after 0, 7, 14, 21, and 28 days of storage. Dipping in 75 degrees C water, lactic acid, and acetic acid resulted in immediate pathogen reductions of 1.4 to 2.0, 1.8 to 2.6, and 1.4 to 2.4 log CFU/cm2, respectively. After storage at 10 degrees C for 28 days, populations of L. monocytogenes on meat treated with 55 degrees C water increased by ca. 1.6 to 1.8 log CFU/cm2. The pathogen remained at low population levels (1.6 to 2.8 log CFU/cm2) on acid-treated meat, whereas populations on meat treated with 75 degrees C water increased rapidly, reaching levels of 3.6 to 4.6 log CFU/cm2 by day 14. During storage at 4 degrees C, there was no growth of the pathogen for at least 21 days in samples treated with 55 and 75 degrees C water, and periods of no growth were longer for acid-treated samples. There were no differences between acid-adapted and nonadapted organisms across treatments with respect to survival or growth. In conclusion, the dipping of meat inoculated with L. monocytogenes into acid solutions reduced and then inhibited the growth of the pathogen during storage at 4 and 10 degrees C, while dipping in hot water allowed growth despite initial reductions in pathogen contamination. The results of this study indicate a residual activity of acid-based decontamination treatments compared with water-based treatments for refrigerated (4 degrees C) or temperature-abused (10 degrees C) lean beef tissue in vacuum packages, and these results also indicate that this activity may not be counteracted by prior acid adaptation of L. monocytogenes.


Assuntos
Manipulação de Alimentos/métodos , Listeria monocytogenes/fisiologia , Carne/microbiologia , Ácido Acético/farmacologia , Adaptação Fisiológica , Animais , Bovinos , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Concentração de Íons de Hidrogênio , Ácido Láctico/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Temperatura , Fatores de Tempo , Vácuo
19.
Endoscopy ; 34(3): 220-2, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11870573

RESUMO

BACKGROUND AND STUDY AIM: Fistula occlusion is not achieved in some fistulas with complex branches. To obtain early fistula closure in such cases, we insert a double-lumen catheter into each fistula branch, with the aid of a guide wire positioned using a small-caliber endoscope, and attempt selective infusion of fibrin glue. PATIENTS AND METHODS: Following removal of foreign bodies and necrotic granulation, we applied the selective occlusion method under fistuloscopic control to seven intractable external fistulas with complex branches, in which fistula closure had not been obtained by a simple occlusion method (SOM). All the fistulas were complex with more than two branches. RESULTS: Fistula occlusion was obtained within 2 weeks in six of the seven patients, and there has been no sign of recurrence over a follow-up period of 4 - 59 months (average 29.8 months). CONCLUSION: Selective occlusion under fistuloscopy is highly effective for intractable external fistulas with complex branches.


Assuntos
Endoscopia Gastrointestinal , Adesivo Tecidual de Fibrina/administração & dosagem , Fístula/terapia , Complicações Pós-Operatórias/terapia , Adesivos Teciduais/administração & dosagem , Procedimentos Cirúrgicos do Sistema Digestório , Humanos
20.
Lett Appl Microbiol ; 34(1): 7-12, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11849484

RESUMO

AIMS: To investigate whether Escherichia coli O157:H7 maintains acid tolerance in water meat decontamination washing fluids. METHODS AND RESULTS: A rifampicin-resistant derivative of E. coli O157:H7 strain ATCC 43895 was inoculated (10(5) cfu ml(-1)) in spray-washings from meat sprayed with cold (10 degrees C) or hot (85 degrees C) water, stored at 10 degrees C for up to 14 days, and its acid tolerance was assessed at 2 and 8 days by exposure to broth or new washings adjusted to pH 3.5 or 3.7 with lactic or acetic acid. The pathogen survived in the water washings, but it was outgrown by the natural, Pseudomonas-like flora, and it was sensitized to acid. CONCLUSIONS: The acid tolerance of E. coli O157:H7 decreases following exposure to non-acid, but otherwise stressful, conditions prevailing in water meat washings at 10 degrees C. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings suggest that the more intense use of water-based technologies should be included in meat decontamination strategies because they may contribute to enhanced meat safety by inducing acid sensitization in E. coli O157:H7.


Assuntos
Escherichia coli O157/crescimento & desenvolvimento , Carne/microbiologia , Animais , Bovinos , Concentração de Íons de Hidrogênio , Segurança , Microbiologia da Água
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