Alpha fetoprotein, ultrasound, computerized tomography and magnetic resonance imaging for detection of hepatocellular carcinoma in patients with advanced cirrhosis.

BACKGROUND: Serum alpha fetoprotein (AFP), ultrasound, computerized tomography scanning, and magnetic resonance imaging are commonly used to screen for hepatocellular carcinoma (HCC) in patients with cirrhosis. AIM: To assess the accuracy of screening in advanced cirrhosis. METHODS: The study group consisted of 239 patients with proven HCC in the explanted liver at the time of liver transplant. AFP and imaging were done at referral and serially until transplant. RESULTS: Hepatocellular carcinoma was detected before liver transplant in 78% and discovered incidentally in 22%. The cause of cirrhosis was hepatitis C (HCV) (55%), hepatitis B (HBV) (17%), alcohol (9%), and other/unknown (19%). Although AFP was elevated 62%, the median level was 15 ng/mL. Only 26%, 15% and 13% were more than 100, 400 and 1000 ng/mL, respectively. By comparison, AFP was elevated in 20% without HCC, but exceeded 100 ng/mL in only 3%. The overall accuracy of AFP was poor regardless of the cutoff. Magnetic resonance imaging was more accurate than computerized tomography or ultrasound in detecting tumour, particularly when performed within 3 months of transplant. CONCLUSIONS: Magnetic resonance imaging is most sensitive for imaging HCC and best reflects actual tumour size. AFP is insensitive and adds little to screening strategies, but has prognostic value when extremely elevated.

Induced Resistance by Penicillium oxalicum Against Fusarium oxysporum f. sp. lycopersici: Histological Studies of Infected and Induced Tomato Stems.

ABSTRACT Tomato (Lycopersicon esculentum) plants of 'Lorena' were induced with a conidial suspension (10(7) conidia per ml) of Penicillium oxalicum before inoculation with Fusarium oxysporum f. sp. lycopersici, the wilt pathogen. Histological changes occurred in plants under both growth chamber and glasshouse culture conditions and there was a reduction of disease severity. In noninduced plants, the pathogen produced almost a complete loss of cambium (75 to 100% reduction), an increase in the number of bundles, and a decrease in the number of xylem vessels (20% reduction), in which the diameter also was reduced by 20 to 30% in hypocotyls and epicotyls. The percentage of vessels colonized by F. oxysporum f. sp. lycopersici was positively correlated to the area under the disease progress curve (AUDPC). However, plants induced with P. oxalicum showed less disease, did not lose the cambium, had a lower number of bundles, and had less vascular colonization by F. oxysporum f. sp. lycopersici (35 to 99%). These effects also were observed in 'Precodor', which is susceptible to races 1 and 2 of F. oxysporum f. sp. lycopersici, and partially in 'Ramón', which is resistant to both races. Renewed or prolonged cambial activity that led to the formation of additional secondary xylem could be one of the reasons for disease reduction in P. oxalicum-induced tomato plants.

Sarcoidosis: simulando hasta el final / No disponible

Describimos un caso de sarcoidosis pulmonar cuya presentación radiológica sugería inicialmente la presencia de una neoplasia pulmonar. Están descritas en la literatura las múltiples formas de presentación que puede tener esta patología a nivel torácico. El diagnóstico de confirmación, tras la realización de una broncoscopia y cobroncoscopia que no resultaron diagnósticas, requirió la realización de una mediastinoscopia con extirpación de varios ganglios mediastínicos que macroscópicamente sugerían la presencia de un proceso tumoral subyacente. La descripción ecobroncoscópica de los ganglios, puede aportar información a la casuística que existe en esta técnica y esta patología. De la misma manera, sirva para recordar las múltiples caras con la que se puede presentar esta enfermedad

We present a case of pulmonary sarcoidosis whose radiological images initially showed the presence of a lung neoplasm. There are multiple appearances within the thorax that we can also find described in literature about pulmonary sarcoidosis. The final diagnosis required us to carry out a mediastinoscopy, after the bronchoscopy and ecobronchoscopy proved to be inconclusive. Under direct inspection the mediastinal lymph nodes looked malignant. The description of the mediastinal lymph nodes from the endobronchial ultrasound should provide additional information to what is already known in this field. In addition, this case will be useful to remind us of the many faces this illness can show

Ethnic differences in the presentation of chronic hepatitis C.

Hispanics comprise 13% of the population in the United States and are the fastest growing minority group. Features of hepatitis C in Hispanics have not been well characterized. The aims of this study were to compare features of hepatitis C among Hispanics, Whites, and African-Americans and to characterize hepatitis C infection in Hispanics. A retrospective analysis was performed on 1225 consecutive patients with hepatitis C seen at the University of Illinois at Chicago including 227 Hispanics, 508 Whites, and 490 African-Americans. Data collection consisted of demographic variables, risk factors for hepatitis C, history of alcohol use, laboratory parameters and liver histology. Pair-wise comparisons showed that Hispanics had higher aminotransferase levels than Whites and African-Americans. Hispanics had higher portal inflammation scores on liver biopsy than African-Americans (P = 0.002) and Whites (P = 0.043). Hispanics had a higher frequency of cirrhosis than African-Americans (P < 0.001) and a trend towards more cirrhosis than Whites (P = 0.165). There was a trend towards a higher prevalence of cirrhosis in Hispanic women (56%) than in Hispanic men (45%) [P = 0.14]. A cross-sectional analysis of patients at our liver center showed that Hispanics with hepatitis C had higher aminotransferase levels, more portal inflammation than Whites and African-Americans, and a higher prevalence of cirrhosis than African-Americans.

[Acquired resistance of M tuberculosis to the antitubercular drugs in Chile from 1988 to 1991]. / Resistencia adquirida del M tuberculosis a las drogas antibacilares en Chile 1988 y 1991.

Acquired drug resistance appears in patients that are or have been in treatment for tuberculosis (relapses, abandons and failures). The aim of this study was to maintain an epidemiologic surveillance on the incidence of acquired drug resistance among previously treated patients and treatment failures. In 896 strains (518 in 1988 and 378 in 1991) coming from these type of patients, the pattern of sensitivity towards agents used in the treatment of tuberculosis was studied. There was an increase in the frequency of acquired resistance from 24.5% in 1988 to 32.3% in 1991. This increment was observed in the group of treatment failures, where the resistance to the combination streptomycin-isoniazid-rifampin had special relevance. This situation is epidemiologically and clinically negative since it generates primary resistance and chronicity. The increment in acquired resistance forces a revision of tuberculosis treatment, specially in its operational features.

Lipases in autolysed cultures of filamentous fungi.

Fifty-one fungi from different genera and strains were checked in plate to determine lipase activity in protein precipitates from their autolysed cultures. Each of them was then analysed at 3.5, 6.5 and 9.2 pH units and, as a consequence, basic lipases with high activity at 9.2 pH were found after 1 h of incubation. Only 25% of the studied fungi showed this lipase activity, among them the best producers were fungi from genus Fusarium (47% of fungi had lipase activity). In addition to lipase activity, Fusaria showed a low hydrolytic activity on cutin and suberin. The genus Aspergillus produced lipase and cutinase activity to a similar extent. Aspergillus nidulans 2544 also showed suberinase activity in a considerable amount. Penicillium species had very low activities. Other species and strains from genus Trichoderma, order Mucorales and class Basidiomycetes, did not show lipase activity in their degradative processes.

Modification of gibberellin production and plant development in Arabidopsis by sense and antisense expression of gibberellin 20-oxidase genes.

Gibberellin (GA) 20-oxidase catalyses consecutive steps late in GA biosynthesis in plants. In Arabidopsis, the enzyme is encoded by a gene family of at least three members (AtGA20ox1, AtGA20ox2 and AtGA20ox3) with differential patterns of expression. The genes are regulated by feedback from bioactive GAs, suggesting that the enzymes may be involved in regulating GA biosynthesis. To investigate this, we produced transgenic Arabidopsis expressing sense or antisense copies of each of the GA 20-oxidase cDNAs. Over-expression of any of the cDNAs gave rise to seedlings with elongated hypocotyls; the plants flowered earlier than controls in both long and short days and were 25% taller at maturity. GA analysis of the vegetative rosettes showed a two- to threefold increase in the level of GA4, indicating that GA 20-oxidase normally limits bioactive GA levels. Plants expressing antisense copies of AtGA20ox1 had short hypocotyls and reduced rates of stem elongation. This was reflected in reduced levels of GA4 in both rosettes and shoot tips. In short days, flowering was delayed and the reduction in the rate of stem elongation was greater. Antisense expression of AtGA20ox2 had no apparent effects in long days, but stem growth in one transgenic line grown in short days was reduced by 20%. Expression of antisense copies of AtGA20ox3 had no visible effect, except for one transgenic line that had short hypocotyls. These results demonstrate that GA levels and, hence, plant growth and development can be modified by manipulation of GA 20-oxidase expression in transgenic plants.

Resultados discordantes de la baciloscopia y el cultivo en el diagnóstico de laboratorio de la tuberculosis renal en Chile / Discordant results of direct microscopy and culture in the laboratory diagnosis of kidney tuberculosis in Chile

Entre enero y junio de 1990, 35 laboratorios de TBC de nivel II de Chile procesaron 13.295 muestras de orina mediante las técnicas de baciloscopia y el cultivo. Ciento cinco muestras de orina fueron positivas a la baciloscopia. De estas, 50 presentaron concomitantemente el cultivo positivo, sin embargo, en otras 49 muestras no hubo crecimiento microbacteriano. Catorce de los 35 laboratorios participantes comunicaron resultados discordantes. De 106 pacientes con exámenes de baciloscopias o cultivos positivos, 18 (17 por ciento) presentaron baciloscopia positiva y cultivo negativo. Nuestros resultados muestran que un número importante de muestras de orina presentan resultado discordante a la baciloscopia y el cultivo, afectando el dignóstico de laboratorio de la TBC renal.

Frecuencia de micobacterias no tuberculosas en Chile / Frequency of non tuberculous mycobacteria in Chile

Se estudian 984 cultivos positivos para micobacterias, obtenidos durante el eño 1985 en los Laboratorios de Bacteriología de la TBC de la red nacional, 963 cepas correspondieron a Micobacterias Tuberculosis humanas y 21 cepas a micobacterias sospechosos de TBC pulmonar. Los resultados se analizan en relación al antecedente de tratamiento, tipo de muestra, condiciones clínicas y morfológicas de las colonias. Las cifras obtenidas a loa parámetros antes señalados, debido a que se tratan de agentes microbianos contaminantes, confirmándose ente hecho en las muestras de aspiración gástrica y bronquial en que la frecuencia de aislamiento es mayor debido a la utilización de instrumental en su obtención. Factores ambientales (humedad, contaminación) desarrollo de las colonias (tamaño) influyeron en la definición de la morfología de los primocultivos. Se aislan 5 cepas de micobacterias no tuberculosas provenientes de 3 casos de micobacteriosis que se encontraban en estudio durante el período de la investigación. Estas micobacterias responsables de enfermedad correspondiente a M. Kansassi, M. Szulgai y M. Avium intracellulere