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1.
J Environ Manage ; 91(9): 1864-71, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20493626

RESUMEN

This paper presents a study of cement replacement by sugar cane bagasse ash (SCBA) in industrial scale aiming to reduce the CO(2) emissions into the atmosphere. SCBA is a by-product of the sugar/ethanol agro-industry abundantly available in some regions of the world and has cementitious properties indicating that it can be used together with cement. Recent comprehensive research developed at the Federal University of Rio de Janeiro/Brazil has demonstrated that SCBA maintains, or even improves, the mechanical and durability properties of cement-based materials such as mortars and concretes. Brazil is the world's largest sugar cane producer and being a developing country can claim carbon credits. A simulation was carried out to estimate the potential of CO(2) emission reductions and the viability to issue certified emission reduction (CER) credits. The simulation was developed within the framework of the methodology established by the United Nations Framework Convention on Climate Change (UNFCCC) for the Clean Development Mechanism (CDM). The State of São Paulo (Brazil) was chosen for this case study because it concentrates about 60% of the national sugar cane and ash production together with an important concentration of cement factories. Since one of the key variables to estimate the CO(2) emissions is the average distance between sugar cane/ethanol factories and the cement plants, a genetic algorithm was developed to solve this optimization problem. The results indicated that SCBA blended cement reduces CO(2) emissions, which qualifies this product for CDM projects.


Asunto(s)
Contaminación del Aire/prevención & control , Dióxido de Carbono/análisis , Conservación de los Recursos Naturales , Materiales de Construcción , Saccharum , Brasil , Carbono , Simulación por Computador , Residuos Industriales , Modelos Teóricos
2.
Neurology ; 62(10): 1687-94, 2004 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-15159463

RESUMEN

BACKGROUND: Daily scheduled opioids (DSO) have been employed in some instances to remediate intractable headache. However, long-term studies of effectiveness, sequelae over several years, predictors of long-term benefit, comparisons of pain-related outcome measures, and prevalence of problematic drug behavior are not available. METHODS: The authors evaluated the results of a treatment program at their institution designed to treat and monitor intractable headache patients administered DSO. Of 160 sequential patients participating in the program, 70 who remained on DSO for at least 3 years qualified for inclusion in an efficacy analysis. Patients completed structured questionnaires at each medical visit as part of routine clinical care. The authors assessed medical records during treatment, and during the 2 years before starting DSO. The primary clinical efficacy variable was percentage improvement in the severe headache index (frequency x severity of severe headaches/week). RESULTS: Analysis of the medical records found 41 (26%) of the original 160 patients with >50% improvement. Patients reported larger improvements on a visual analog scale (mean improvement = 70%) than shown by the medical record (mean improvement = 46%), p < 0.00001. Problem drug behavior (dose violations, lost prescriptions, multisourcing) occurred in 50% of patients, usually involving dose violations. CONCLUSIONS: For a select group of intractable headache patients, DSO can offer significant benefit. However, 74% of those treated either failed to show significant improvement or were discontinued from the program for clinical reasons. The relatively low percentage of patients with demonstrated efficacy and unexpectedly high prevalence of misuse have clinical relevance.


Asunto(s)
Analgésicos Opioides/uso terapéutico , Trastornos de Cefalalgia/tratamiento farmacológico , Adulto , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/efectos adversos , Esquema de Medicación , Sobredosis de Droga/epidemiología , Femenino , Estudios de Seguimiento , Trastornos de Cefalalgia/etiología , Trastornos de Cefalalgia/prevención & control , Humanos , Masculino , Michigan/epidemiología , Trastornos Relacionados con Opioides/epidemiología , Clínicas de Dolor/estadística & datos numéricos , Dimensión del Dolor , Cooperación del Paciente , Resultado del Tratamiento
5.
Clin Chim Acta ; 304(1-2): 49-55, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11165198

RESUMEN

Serum iron indices are believed to be elevated in patients with hepatitis C virus (HCV) infection in connection to the presence of hepatic inflammation, though this hypothesis has never been formally tested. We studied 69 consecutive, unselected anti HCV antibody positive patients, aged 14 to 70 years. Iron, transferrin saturation and ferritin were measured in fasting serum samples. Histologically detectable iron (HDI) as well as histologic grading and staging were estimated semiquantitatively in liver biopsy samples. The median values for serum iron, transferrin saturation and serum ferritin were 24 micromol/l (range, 8-61), 29 percent (range, 6-77) and 170 microg/l (range, 1-954), respectively. At univariate analysis, all three serum iron indices were positively correlated with grading and staging scores, as well as with HDI in the liver; only serum iron was positively correlated with transaminases. At multivariate analysis, independent associations were found between serum iron and the grading score; ferritin and sinusoidal and portal HDI; transferrin saturation and total hepatic HDI. In conclusion, in hepatitis C, serum iron reflects the degree of current hepatic inflammation and necrosis, whereas the extent of progressive deposition of iron in sites of fibrosis is best reflected by serum ferritin. Transferrin saturation is the best predictor of the status of hepatic iron deposits.


Asunto(s)
Hepatitis C Crónica/sangre , Hierro/sangre , Adolescente , Adulto , Anciano , Femenino , Ferritinas/sangre , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
6.
Respiration ; 68(1): 88-90, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11223737

RESUMEN

Empyemas are usually of infectious origin. Noninfectious causes of empyema may be a considerable diagnostic challenge, as exemplified in the present case report. A 21-year-old male presented with high fever, sore throat and myalgias of 1 week duration. In the following days, bilateral pleural effusions developed, with cellular counts in the pleural fluid up to 117 x 10(9)/liter (98% neutrophils). Despite institution of empiric antibiotic therapy, spiking fever continued. All culture studies resulted in being negative. Following the report of a serum ferritin concentration of 6,975 microg/l, adult-onset Still's disease was diagnosed and successfully treated with anti-inflammatory drugs. This case adds adult-onset Still's disease to the list of noninfectious causes of empyema and underlies the value of measuring serum ferritin as a diagnostic tool.


Asunto(s)
Empiema Pleural/tratamiento farmacológico , Empiema Pleural/etiología , Enfermedad de Still del Adulto/complicaciones , Enfermedad de Still del Adulto/diagnóstico , Adulto , Antibacterianos/uso terapéutico , Quimioterapia Combinada , Empiema Pleural/diagnóstico por imagen , Ferritinas/análisis , Estudios de Seguimiento , Humanos , Masculino , Metotrexato/uso terapéutico , Prednisona/uso terapéutico , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
7.
Adv Clin Path ; 5(4): 121-31, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17582936

RESUMEN

Recent years have witnessed tremendous advances in the fields of pathophysiology, diagnosis and management of hereditary hemochromatosis (HH) and other iron overload syndromes, the dreadful consequences of which are fully preventable by early diagnosis and treatment. Missense mutations in HFE, a newly discovered gene encoding for a major histocompatibility class-I like molecule, have been found to be strictly associated with most cases of HH. The mechanisms by which a dysfunctional HFE molecule determines increased absorption of iron in HH are on the way to be fully clarified, due to the availability of a knockout mouse model. Epidemiologic studies have shown that HH is one of the most common human hereditary disorders. The possibility to identify HFE heterozygotes by means of a simple genetic test have prompted studies on the association between HFE mutations and iron overload syndromes different from HH. In the era of the historic completion of the human genome projects, genetic testing for HH may soon qualify for being adopted in universal population screening policies. In the present paper, the recent advances in the fields of genetics and pathophysiology of HH and other iron overload syndromes will be summarized. Furthermore, its clinical features, pathology and treatment will be reviewed, and the emerging issues of cost-effective diagnosis and of possible population screening strategies will be succintly discussed.


Asunto(s)
Hemocromatosis/diagnóstico , Hemocromatosis/fisiopatología , Sobrecarga de Hierro/diagnóstico , Sobrecarga de Hierro/fisiopatología , Animales , Análisis Costo-Beneficio , Pruebas Genéticas/economía , Pruebas Genéticas/métodos , Hemocromatosis/tratamiento farmacológico , Hemocromatosis/genética , Proteína de la Hemocromatosis , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/fisiología , Humanos , Hierro/metabolismo , Sobrecarga de Hierro/tratamiento farmacológico , Sobrecarga de Hierro/genética , Proteínas de la Membrana/genética , Proteínas de la Membrana/fisiología , Ratones , Ratones Noqueados , Mutación Missense/genética
8.
Cancer Detect Prev ; 24(2): 150-5, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10917135

RESUMEN

Because in experimental hepatocarcinogenesis apoptosis increases from normal to preneoplastic to carcinoma tissue, proapoptotic factors, such as activin-A, may represent useful markers for hepatocellular carcinoma (HCC). In this study, serum activin-A was measured in 99 cirrhotic patients, of whom 55 had HCC. Activin-A concentrations were higher in HCC patients (median, 2.33 ng/ml; range, 0.41-8.12) than in patients with nonmalignant cirrhosis (1.28 ng/ml; range, 0.35-6.25) (P < .05). All 12 patients with activin-A greater than 3 ng/ml and serum alpha-fetoprotein greater than 30 ng/ml had HCC, in comparison to 32 of 41 patients who had only one and to 11 of 46 patients who had both markers below these cutoffs (P < .0001). No correlation was found between activin-A and alpha-fetoprotein in the two groups, whereas in patients with HCC, activin-A was strictly correlated with serum aspartate aminotransferase (P < .001). Activin-A mRNA for inhibin betaA subunit was expressed both in tumor and nontumor liver tissues in a case of HCC superimposed on cirrhosis and was not expressed in a case of HCC without cirrhosis. In conclusion, cirrhotic patients with HCC have high serum activin-A, to the production of which both the cirrhotic liver and the liver tumor are likely to contribute.


Asunto(s)
Carcinoma Hepatocelular/sangre , Inhibinas/sangre , Neoplasias Hepáticas/sangre , Proteínas de Secreción Prostática , Activinas , Adulto , Anciano , Anciano de 80 o más Años , Aspartato Aminotransferasas/sangre , Biomarcadores/sangre , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Femenino , Humanos , Inhibinas/genética , Cirrosis Hepática/sangre , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Péptidos/genética , Péptidos/metabolismo , ARN Mensajero/análisis , alfa-Fetoproteínas/metabolismo
9.
J Head Trauma Rehabil ; 14(1): 70-80, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9949247

RESUMEN

This study addresses (1) the relationship between headache presence/intensity at time of testing and neurocognitive performance, and (2) the probability that testing triggers or intensifies pain. Subjects were 125 patients with chronic posttraumatic headache (mean = 2.67 years post injury) who completed a 4-hour test battery emphasizing memory. Comparisons of 34 individual tests/subtests and the five Wechsler Memory Scale-Revised (WMS-R) indices of relative memory impairment for 73 patients with no headache or mild headache versus 52 patients with moderate to severe pain revealed no significant differences. Testing intensified existing headaches for 55% but triggered headache for only 1 of 20 (5%; P =.00003). Results support the validity of neuropsychological test performance regardless of pain level, although testing can be painful.


Asunto(s)
Cefalea , Pruebas Neuropsicológicas , Adulto , Enfermedad Crónica , Traumatismos Craneocerebrales/complicaciones , Femenino , Cefalea/etiología , Cefalea/psicología , Humanos , Masculino , Procesos Mentales , Índice de Severidad de la Enfermedad
10.
Headache ; 36(5): 300-6, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8682671

RESUMEN

The Cognitive Difficulties Scale, a self-report measure of cognitive functioning, was administered to 111 consecutive adult referrals with posttraumatic head pain subsequent to mild to moderate head and/or cervical flexion-extension injuries who were treated at a clinic specializing in head pain and neurological disorders. Factor analysis of the Cognitive Difficulties Scale yielded seven meaningful factors corresponding to the types of memory inefficiencies often associated with neurological dysfunction. Further analyses comparing the Cognitive Difficulties Scale factor scores to objective tests of mental status, memory, and depressed mood demonstrated limited relationships between specific Cognitive Difficulties Scale factor scores and these measures of cognitive performance and behavior. The Cognitive Difficulties Scale appears helpful in assisting this patient population with treatment planning and specific remediation tied to everyday situations.


Asunto(s)
Trastornos del Conocimiento/diagnóstico , Cognición , Traumatismos Craneocerebrales/complicaciones , Cefalea/etiología , Cefalea/psicología , Pruebas Psicológicas , Autoevaluación (Psicología) , Actividades Cotidianas , Adolescente , Adulto , Anciano , Atención , Trastornos del Conocimiento/etiología , Depresión/diagnóstico , Depresión/etiología , Humanos , Memoria , Persona de Mediana Edad
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