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1.
Environ Sci Technol ; 39(12): 4655-65, 2005 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-16047806

RESUMEN

Anthropogenic cycling of silver in 1997 is presented using three discrete governmental units: 64 countries encompassing what we believe to be over 90% of global silver flows, 9 world regions, and the entire planet. Using material flow analysis (MFA) techniques, the country level cycles are aggregated to produce the regional cycles, which are used to form a "best estimate" global cycle. Interesting findings include the following: (1) several silver-mining countries export ore and concentrate but also import silver-containing semiproducts and products; (2) the level of development for a country, as indicated by the gross domestic product, is a fair indicator of silver use, but several significant outliers exist; (3) the countries with the greatest mine production include Mexico, the United States, Peru, and China, whereas the United States, Japan, India, Germany, and Italy lead in the fabrication and manufacture of products; (4) North America and Europe's use of silver products exceed that of other regions on a per capita basis; (5) global silver discards, including tailings and separation waste, totaled approximately 57% of the silver mined; (6) approximately 57% of the silver entering waste management globally is recycled; and (7) the amount of silver entering landfills globally is comparable to the amount found in tailings. The results of this MFA lay the basis for further analysis, which in turn can offer insight into natural resource policy, the characterization of environmental impact, and better resource management.


Asunto(s)
Comercio/economía , Materiales Manufacturados/economía , Metalurgia/economía , Minería/economía , Modelos Teóricos , Plata/química , Administración de Residuos
2.
Antimicrob Agents Chemother ; 49(3): 1010-6, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15728896

RESUMEN

The absence of any formally licensed antiadenovirus drugs and the increasing incidence of life-threatening adenovirus infections in immunosuppressed patients warrant the development of effective antiadenovirus compounds. A detailed study was performed on the antiadenovirus activities of several classes of nucleoside and nucleotide analogues in human embryonic lung fibroblast cells. The antiadenovirus activities were evaluated by three methods, viz., evaluating the adenoviral cytopathic effect, monitoring cell viability by a colorimetric assay, and real-time PCR quantitation of viral DNA as a direct parameter for virus replication. The most active and selective compounds were the acyclic nucleoside phosphonate analogues cidofovir, its adenine analogue (S)-9-(3-hydroxy-2-phosphonylmethoxypropyl)adenine [(S)-HPMPA], and the new derivative (S)-2,4-diamino-6-[3-hydroxy-2-(phosphonomethoxy)propoxy]pyrimidine [(S)-HPMPO-DAPy]; the N7-substituted acyclic derivative 2-amino-7-(1,3-dihydroxy-2-propoxymethyl)purine (S-2242); and the 2',3'-dideoxynucleoside analogues zalcitabine and alovudine. No antiadenovirus activity was observed for the antiviral drugs ribavirin, foscarnet, acyclovir, penciclovir, and brivudin, while ganciclovir displayed modest activity. However, in human osteosarcoma cells transfected with herpes simplex virus thymidine kinase, ganciclovir demonstrated highly potent antiadenovirus activity, suggesting that the efficacy of ganciclovir against adenovirus is limited by inefficient phosphorylation in adenovirus-infected cells, rather than by insufficient inhibition at the viral DNA polymerase level. Collectively, our antiviral data show that the adenovirus DNA polymerase exhibits sensitivity to a relatively broad spectrum of inhibitors and should be studied further as an antiviral target in antiadenovirus drug development programs.


Asunto(s)
Adenoviridae/efectos de los fármacos , Antivirales/farmacología , Nucleósidos/farmacología , Nucleótidos/farmacología , Ganciclovir/farmacología , Humanos , Reacción en Cadena de la Polimerasa , Timidina Quinasa/análisis
3.
Clin Infect Dis ; 38(7): e57-62, 2004 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-15034848

RESUMEN

A neonate with lower-limb hypoplasia, cutaneous scars, bilateral chorioretinitis, and multiple brain abnormalities is presented. Intrauterine herpes simplex virus type 2 (HSV-2) infection was established on the basis of serological testing of the mother and viral cultures of the child's cutaneous lesions, obtained soon after birth. This is, to the best of our knowledge, the first case of a patient with in utero-acquired HSV-2 infection presenting with a limb hypoplasia. It illustrates that, in addition to congenital varicella-zoster syndrome, HSV-2 infection should also be considered in patients presenting with limb hypoplasia.


Asunto(s)
Herpes Simple/fisiopatología , Herpesvirus Humano 2 , Complicaciones Infecciosas del Embarazo/virología , Adulto , Encéfalo/anomalías , Coriorretinitis/etiología , Femenino , Herpes Simple/virología , Herpes Zóster/congénito , Herpes Zóster/fisiopatología , Humanos , Recién Nacido , Embarazo
4.
Environ Sci Technol ; 38(4): 1242-52, 2004 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-14998044

RESUMEN

A comprehensive contemporary cycle for stocks and flows of copper is characterized and presented, incorporating information on extraction, processing, fabrication and manufacturing, use, discard, recycling, final disposal, and dissipation. The analysis is performed on an annual basis, ca. 1994, at three discrete governmental unit levels--56 countries or country groups that together comprise essentially all global anthropogenic copper stocks and flows, nine world regions, and the planet as a whole. Cycles for all of these are presented and discussed, and a "best estimate" global copper cycle is constructed to resolve aggregation discrepancies. Among the most interesting results are (1) transformation rates and recycling rates in apparently similar national economies differ by factors of two or more (country level); (2) the discard flows that have the greatest potential for copper recycling are those with low magnitude flows but high copper concentrations--electronics, electrical equipment, and vehicles (regional level); (3) worldwide, about 53% of the copper that was discarded in various forms was recovered and reused or recycled (global level); (4) the highest rate of transfer of discarded copper to repositories is into landfills, but the annual amount of copper deposited in mine tailings is nearly as high (global level); and (5) nearly 30% of copper mining occurred merely to replace copper that was discarded. The results provide a framework for similar studies of other anthropogenic resource cycles as well as a basis for supplementary studies in resource stocks, industrial resource utilization, waste management, industrial economics, and environmental impacts.


Asunto(s)
Conservación de los Recursos Naturales , Cobre/química , Modelos Teóricos , Administración de Residuos , Cobre/análisis , Ambiente , Industrias , Materiales Manufacturados
5.
J Pediatr Hematol Oncol ; 21(6): 554-6, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10598673

RESUMEN

Langerhans cell histiocytosis (LCH) with subsequent viral-associated hemophagocytic syndrome (VAHS) or secondary hemophagocytic lymphohistiocytosis (HLH) is extremely rare. A 15-month-old girl with disseminated LCH experienced three episodes of VAHS during maintenance therapy. Viral infection, with influenza A, herpes simplex, and adenovirus, respectively, was documented at each episode. She recovered each time after interruption of maintenance therapy. The occurrence of fever and pancytopenia in patients with chemotherapy-treated LCH can be associated with VAHS and not with relapsing LCH.


Asunto(s)
Histiocitosis de Células de Langerhans/complicaciones , Histiocitosis de Células no Langerhans/complicaciones , Inmunosupresores/uso terapéutico , Mercaptopurina/uso terapéutico , Metotrexato/uso terapéutico , Virosis/complicaciones , Adenovirus Humanos/aislamiento & purificación , Biopsia con Aguja , Médula Ósea/patología , Quimioterapia Combinada , Femenino , Histiocitosis de Células de Langerhans/tratamiento farmacológico , Histiocitosis de Células de Langerhans/inmunología , Histiocitosis de Células no Langerhans/virología , Humanos , Lactante , Virus de la Influenza A/aislamiento & purificación , Recurrencia , Simplexvirus/aislamiento & purificación , Piel/patología
9.
J Virol Methods ; 42(2-3): 251-63, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8514843

RESUMEN

Ten to fifteen percent of posttransfusion viral hepatitis cases are still caused by HBV despite mandatory third generation screening procedures for HBsAg. There is thus an urgent need for a simple, time-cost-effective, but very sensitive test for routine HBV DNA detection in serum. Nested-primed PCR has been shown to detect purified HBV DNA at its infectivity threshold in serum. Since this is too labor-intensive for routine testing, we assessed the efficiency of a Fast PCR procedure, of three pairs of primers, and of thirty-five simple serum pretreatments with the aim to achieve the same sensitivity level. Using ten-fold dilution in phosphate buffered saline as pretreatment and Fast PCR for 99 cycles, we were able to detect HBV DNA at the 2 x 10(3)/ml level in serum. Using either NaOH denaturation or sodium octanoate thermoprotection as pretreatment and Fast PCR for 99 cycles, we were able to detect HBV DNA at its infectivity threshold in serum, while the classical phenol/chloroform/isoamylic alcohol/isopropanol/ethanol DNA purification procedure enabled us to reach the 10 virus particles/ml level. These results suggest that denatured albumin is responsible for the well known inhibitory effect of serum proteins on Taq polymerase. Because of its simplicity and its lower risk of sample-to-sample cross-contamination, the sodium octanoate thermoprotection method was chosen for routine clinical detection of HBV in serum. The clinical usefulness of this approach is demonstrated by the results obtained with HBsAg-negative acute hepatitis B incubation sera and with anti HBe-positive chronic hepatitis B sera.


Asunto(s)
ADN Viral/sangre , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B/sangre , Reacción en Cadena de la Polimerasa/métodos , Proteínas Sanguíneas/farmacología , Caprilatos/farmacología , ADN Viral/genética , ADN Polimerasa Dirigida por ADN/efectos de los fármacos , Virus de la Hepatitis B/genética , Humanos , Desnaturalización Proteica/efectos de los fármacos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Albúmina Sérica/farmacología , Polimerasa Taq , Factores de Tiempo
10.
J Med Virol ; 39(4): 273-7, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8388024

RESUMEN

The epidemiologic studies with the least selection bias do not support the hypothesis that HPV types 16 and/or 18 are strongly associated with cervical cancer. In this preliminary report, we describe our findings regarding type 16, 18, and 33 detection rates in 323 normal and 71 dysplastic or neoplastic cervical scrapes using fast multiplex PCR. This modified PCR technique has been shown to be the most sensitive, specific, and reproducible DNA detection method for large epidemiologic studies. The results indicate a high relative risk of increasingly severe cervical abnormality associated with the presence of high-risk HPV DNA. The analysis of the prevalence and age data according to CIN status by non-parametric statistic tests highlights the importance of other factors inversely correlated with age in the cervical transformation process.


Asunto(s)
Papillomaviridae/aislamiento & purificación , Infecciones Tumorales por Virus/microbiología , Displasia del Cuello del Útero/microbiología , Neoplasias del Cuello Uterino/microbiología , Adulto , Factores de Edad , Bélgica/epidemiología , Línea Celular , Distribución de Chi-Cuadrado , Femenino , Células HeLa , Humanos , Reacción en Cadena de la Polimerasa , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Infecciones Tumorales por Virus/complicaciones , Displasia del Cuello del Útero/epidemiología , Displasia del Cuello del Útero/etiología , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/etiología
12.
J Med Virol ; 38(3): 226-32, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1337551

RESUMEN

To evaluate the risk factors associated with persistence of human papillomaviruses (HPV) types 16, 18, and 33 in the normal cervix, a prospective study was carried out in Belgium of 323 women without cytological evidence of cervical intraepithelial neoplasia. Demographic and clinical data were obtained by interview, and HPV DNA was assayed in cervical-swab specimens using the Fast Multiplex Polymerase Chain Reaction-based screening and confirmatory tests. A multivariable linear regression model was constructed using four well-known risk factors: the use of an oral contraceptive which is either triphasic, or monophasic and containing ethynylestradiol in association with either norethysterone, or levonorgestrel, or lynestrenol, or gestoden, or estrogenic and containing estriol (P = 8 x 10(-5)), a positive history of genital herpes simplex virus (HSV) infection (P = 10(-4)), an age inferior or equal to 30 years (P = 0.012), and cigarette smoking (P = 0.020). Crude and adjusted relative risks were calculated for each HPV persistence predictor. The data and the results of the molecular biology of high-risk genital HPVs are consistent with the hypothesis that the use of an oral contraceptive containing simultaneously and continuously both a potent estrogen and a high activity progestative is necessary to enhance significantly HPV transcription. These observations are also consistent with the hypothesis that the oral contraceptives and HSV genital infection are responsible for HPV persistence in the normal cervix but not for HPV-induced cervical transformation.(ABSTRACT TRUNCATED AT 250 WORDS)


PIP: This prospective study evaluated the risk factors associated with persistence of human papillomaviruses (HPVs) types 16, 18, and 33 in the normal cervix. Cervical specimens were obtained from 323 women attending the cervical cancer screening clinic classified as normal on the basis of exfoliative cytology. Demographic, sexual, behavioral, and clinical data were obtained by interview. Crude and adjusted relative risks were calculated for each HPV persistence predictor. The data and the results of the molecular biology of high-risk genital HPVs were consistent with the hypothesis that the use of an oral contraceptive containing simultaneously and continuously both a potent estrogen and a high activity progestative was necessary to enhance significantly HPV transcription. A relatively weak correlation was found for cigarette smoking. In addition, it is noted that several other risk factors associated with young age, such as a high number of sexual partners, is also a predictor of acquiring HPV.


Asunto(s)
Cuello del Útero/microbiología , Papillomaviridae/fisiología , Infecciones Tumorales por Virus/microbiología , Enfermedades del Cuello del Útero/microbiología , Factores de Edad , Enfermedad Crónica , Anticonceptivos Hormonales Orales , Femenino , Herpes Simple , Humanos , Análisis Multivariante , Papillomaviridae/genética , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , Análisis de Regresión , Factores de Riesgo , Fumar , Infecciones Tumorales por Virus/diagnóstico , Infecciones Tumorales por Virus/epidemiología , Enfermedades del Cuello del Útero/diagnóstico , Enfermedades del Cuello del Útero/epidemiología
14.
J Med Virol ; 36(4): 279-82, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1315840

RESUMEN

Because in situ/filter hybridisation is not sensitive enough and because classical polymerase chain reaction (PCR) protocols are generally not sufficiently reproducible and specific, there is little accurate information on the prevalence of human papillomaviruses (HPV) 16, 18, and 33 infections in women without dyskaryotic changes of the cervix. In our hands, our Fast Multiplex PCR protocol has always been the most sensitive, specific, and reproducible DNA detection assay in all the microbiological and haematological applications we attempted (Vandenvelde C, Verstraete M, Van Beers D [1990]: Journal of Virological Methods 30:215-228; Vandenvelde C, Scheen R, Corazza F, Van Beers D [1991a]: Journal of Experimental and Clinical Hematology 33:293-297; Vandenvelde C, Scheen R, Van Beers D, Fondu P [1991b]: Journal of Experimental and Clinical Hematology 30:25-29). Using this new technique, cervical scrapes from 336 Belgian women attending the cervical cancer screening clinic were examined for the presence of these three high-risk genital papillomaviruses. Positive results were confirmed using another set of HPV-specific primers. Exactly one sixth of our population was found positive for one or more of these HPVs. Types 33 and 16 were significantly more prevalent than type 18. The nonparametric statistical analysis of the data suggests that some risk factors such as particular sexual habits, that are inversely related to age, must exist.


Asunto(s)
Enfermedades de los Genitales Femeninos/microbiología , Papillomaviridae/genética , Reacción en Cadena de la Polimerasa , Infecciones Tumorales por Virus/epidemiología , Adulto , Anciano , Secuencia de Bases , Bélgica/epidemiología , ADN Viral/genética , Femenino , Humanos , Persona de Mediana Edad , Datos de Secuencia Molecular , Prevalencia , Riesgo , Neoplasias del Cuello Uterino/microbiología
15.
Eur J Clin Microbiol Infect Dis ; 10(12): 1073-6, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1802701

RESUMEN

A commercial enzyme immunomembrane filter assay (EIFA) for respiratory syncytial virus (RSV) was compared prospectively with isolation in cell culture and an enzyme immunoassay. A total of 595 respiratory specimens, mostly from pediatric patients, were examined. The EIFA was 70.96% sensitive and 72.40% specific in comparison with cell culture. Results for 40 specimens (6.72%) were uninterpretable, mainly due to filtration difficulties. Twenty-one (25%) of 84 specimens whose results were initially considered false-positive were subsequently confirmed positive after a blocking test with bovine anti-RSV serum. On the basis of the total number of confirmed positive results, the sensitivity and the specificity of the test were 87.90% and 75.77%, respectively.


Asunto(s)
Técnicas para Inmunoenzimas , Virus Sincitiales Respiratorios/aislamiento & purificación , Infecciones por Respirovirus/diagnóstico , Células Cultivadas , Estudios de Evaluación como Asunto , Reacciones Falso Positivas , Humanos , Sensibilidad y Especificidad
16.
Nouv Rev Fr Hematol (1978) ; 33(1): 25-9, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1945822

RESUMEN

Available methods for the detection of minimal residual disease in hematologic malignancies are limited by their poor sensitivity and/or complexity. In order to avoid these drawbacks, we used the fast PCR technique to amplify the hypervariable chain-determining region 3 (CDR 3) of the human immunoglobulin heavy-chain gene in boiled marrow nucleated cells. This enabled us to detect malignant B-cells down to a dilution of 1 in 1,300 marrow nucleated cells within 7 hours of sampling. This new quantitative method should be useful for monitoring therapy and detecting early disease relapse in B-lymphoproliferative disease since it is 10 to 60 times as sensitive as Southern blotting.


Asunto(s)
Leucemia de Células B/diagnóstico , Linfocitos B , Secuencia de Bases , Humanos , Linfoma no Hodgkin/diagnóstico , Trastornos Linfoproliferativos/diagnóstico , Datos de Secuencia Molecular , Mieloma Múltiple/diagnóstico , Reacción en Cadena de la Polimerasa , Factores de Tiempo
17.
Nouv Rev Fr Hematol (1978) ; 33(4): 293-7, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1664096

RESUMEN

Available methods for the detection of minimal residual disease in T-cell malignancies are limited by their poor sensitivity and/or by their complexity. With the aim of avoiding these drawbacks, we used the Fast PCR technique in order to amplify V delta 1-(D delta 1)-(D delta 2)-J delta 1 and V gamma I family-J gamma junctional sequences from nucleated cells of boiled bone marrow. We were thus able to detect malignant T-cells down to a dilution of 1 in 665 nucleated marrow cells, in less than 4 hours after sampling. This new quantitative method is promising for monitoring therapy and detecting early disease relapse in T-lymphoproliferative disease, since it is 2 to 35 fold more sensitive than Southern blotting.


Asunto(s)
Examen de la Médula Ósea/métodos , Reordenamiento Génico de la Cadena delta de los Receptores de Antígenos de los Linfocitos T , Reordenamiento Génico de la Cadena gamma de los Receptores de Antígenos de los Linfocitos T , Leucemia de Células T/genética , Linfoma de Células T/genética , Reacción en Cadena de la Polimerasa , Secuencia de Bases , Preescolar , ADN de Neoplasias/genética , Estudios de Seguimiento , Humanos , Leucemia/genética , Leucemia de Células T/patología , Linfoma , Linfoma de Células T/patología , Trastornos Linfoproliferativos/genética , Masculino , Datos de Secuencia Molecular , Mieloma Múltiple/genética , Recurrencia Local de Neoplasia/diagnóstico , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad
18.
J Virol Methods ; 30(2): 215-27, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2175751

RESUMEN

An assessment of optimal conditions for rapid simultaneous amplification of multiple human papillomavirus (HPV) sequences has been made using Thermus aquaticus DNA polymerase. All variables of practical value were studied by amplifying known target-sequences from ten-fold dilutions of well characterized cell lines. In our hands, Fast Multiplex PCR (FM-PCR), the technique of running multiple PCR reactions simultaneously with minimum incubation time at each temperature, was highly sensitive (amplification factor = 5 x 10(9) after 50 cycles), specific (100%) and reproducible (100%) for several microbiological applications. Diagnosis was generally obtained in less than 5 h after sampling. The results show that, after optimization of assay conditions, efficiency and specificity of Multiplex PCR depends exclusively on the primers design and concentration of the primers.


Asunto(s)
Papillomaviridae/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Infecciones Tumorales por Virus/diagnóstico , Secuencia de Bases , Línea Celular , ADN Viral/genética , Reacciones Falso Positivas , Calor , Humanos , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Papillomaviridae/genética , Mapeo Restrictivo , Infecciones Tumorales por Virus/microbiología
19.
J Biol Buccale ; 18(2): 71-4, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2170348

RESUMEN

HSV1 suspensions were pre-incubated in a lactoperoxidase thiocyanate oxidizing system before inoculation in MRC5 fibroblast cultures. This pre-treatment could either delay or even abolish the HSV1 cytopathic potentiality. The effect was found to be time-dependent.


Asunto(s)
Lactoperoxidasa/farmacología , Simplexvirus/efectos de los fármacos , Tiocianatos/farmacología , Antivirales , Línea Celular , Fibroblastos/fisiología , Humanos , Oxidación-Reducción , Simplexvirus/fisiología , Factores de Tiempo
20.
Acta Cardiol ; 45(4): 329-33, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2239031

RESUMEN

Myocarditis, pericarditis and endocarditis are rare manifestations of Legionella pneumophila infection. We describe a case of myocarditis complicated with a potentially fatal arrhythmia: "torsades de pointes".


Asunto(s)
Enfermedad de los Legionarios/complicaciones , Miocarditis/microbiología , Torsades de Pointes/etiología , Anciano , Electrocardiografía , Humanos , Masculino , Torsades de Pointes/diagnóstico
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