New records of Trichinella patagoniensis from Argentina.

Trichinella spiralis was long considered the sole Trichinella species in Argentina. However, since 2004, various Trichinella species, including the encapsulated Trichinella patagoniensis and Trichinella britovi, as well as the unencapsulated Trichinella pseudospiralis, have been detected in the country. The present study aimed to identify Trichinella ML at the species level from cougars naturally infected from Argentina. To this end, muscle tissue samples from one cougar each from Córdoba, Neuquén, and Santa Cruz Provinces were individually analysed using the artificial digestion technique. DNA extraction and molecular identification of Trichinella species were conducted on individual muscle larvae by PCR amplification of the ESV region and subsequent PCR amplification and sequencing of the COI gene. Morphological analysis revealed muscle larvae with characteristics consistent with Trichinella genus. PCR revealed a single band of approximately 127 bp for each individual muscle larva. PCR amplification of the COI gene from each isolate generated a 309 bp band. Sequencing of the mitochondrial COI gene confirmed the identity of the parasite as T. patagoniensis. The present study documents new occurrences of T. patagoniensis in Puma concolor from Argentina, including the first detection of T. patagoniensis in Puma concolor from Córdoba and Neuquén Province. These findings expand the limited knowledge of T. patagoniensis distribution in Argentina.

Toxocara canis infections in a pig model: immunological, haematological and blood biochemistry responses.

The immunological, haematological and enzymatic responses to the inoculation in pigs of 100,000 embryonated eggs of Toxocara canis were studied. Fifteen females were inoculated and three remained as controls. Haematological values were analysed from day 7 p.i. until day 126 p.i. In the inoculated group, white blood cells were raised on day 14 p.i. and eosinophil values on days 7, 14, 21, 35 and 49 p.i. showing significant differences compared with controls (P < 0.05). Absolute eosinophil counts (per ml) presented two rises, the first on days 7, 14 and 21 p.i. and the second on days 35 and 49 p.i. Blood biochemistry was maintained within normal values. Serological examination by ELISA to determine antibody levels against Toxocara canis L2/L3 excretory-secretory (ES) antigens showed values higher than the positive cut-off (1:32) from day 7 p.i. and until the end of the study on day 126 p.i., presenting two peaks: one on day 28 p.i. and the second covering days 49 to 56 p.i. Western blots of sera of inoculated animals presented, from day 7 p.i., two polypeptide bands of 55 and 70 kDa MW and, from day 56 p.i., an additional band of 120 kDa MW, all of which persisted until the end of the study. Immunological responses were sustained over time. No direct correlation was observed between the rise in eosinophils and antibody titres. To validate the conclusions, more studies are required on the polypeptide bands.

Prevalence of canine dirofilariosis in the City of Buenos Aires and its outskirts (Argentina).

During the past 10 years, the prevalence of canine dirofilariosis in the City of Buenos Aires and its outskirts, particularly in the northern and southern areas, has increased significantly. In the present work, studies were carried out in dogs living in the city and in its northern, western and southern outskirts from 1997 to 2001. For this purpose, 782 blood samples were collected and analyzed to determine circulating antigen, processed with the Witness Merial antigen test. The samples resulted in negative tests for subjects who lived in the city; however, 17.7 and 23.5% of the tests were positive from the northern and southern outskirts, respectively. When analyzed by sex, positive results were distributed as follows: 62.5% males and 37.5% females (P<0.05). No significant statistical difference was found on comparing purebred and cross-breds (P<0.05). It is interesting to point out the geographical distribution of the disease, which confirms that ecological factors such as water currents, abundant vegetation and the existence of mosquitoes all year round, are important for the biological cycle of Dirofilaria immitis.

Interferon-alpha plus low-dose cytosine arabinoside in advanced phase chronic myelogenous leukaemia patients.

Twenty-nine late chronic and accelerated phase chronic myelogenous leukaemia (CML) patients were entered in a pilot study designed to test the therapeutic efficacy of treatment with interferon-alpha (IFN-alpha) and low-dose cytosine arabinoside (ARA-C). IFN-alpha was administered at a dose of 2-10 x 10(6) IU/day and ARA-C at 15 mg/m2/day for 14 days each month. The treatment was well tolerated by 73% of the patients. Side effects were mainly asthenia, anorexia, anaemia and piastrinopenia. Haematological and cytogenetic responses were evaluated in the 19 patients who received more than 6 cycles. Four complete haematological response, 7 partial haematological response, 6 minor haematological response, 2 stable disease were obtained in this patient group. Two complete cytogenetic responses and 2 minor cytogenetic responses were detected in these patients. Suppression of secondary Ph' positive clones which appeared during the previous IFN-alpha treatment was documented in 3 accelerated phase patients after ARA-C was added to their IFN-alpha treatment. It would therefore seem that late chronic and accelerated phase CML patients benefit from combined IFN-alpha/ARA-C treatment and achieve haematological and cytogenetic responses not obtained during previous treatment without being exposed to undue toxicity. However, we cannot judge whether it offers any advantage in terms of survival.

Double-blind randomized phase I study on the clinical tolerance and pharmacodynamics of natural and recombinant interferon-beta given intravenously.

The clinical tolerance and biological properties of 6 x 10(6) IU of Chinese hamster glycosylated recombinant interferon-beta (rHuIFN-beta) and natural IFN-beta (Frone) given i.v. were compared in 12 healthy volunteers in a randomized cross-over, double-blind trial. All subjects received a single injection of each type of IFN-beta. Both were well tolerated and provoked similar changes in clinical indices. Serum neopterin (Np) values increased significantly from the 24th to 72nd h post-injection of rHuIFN-beta and Frone. beta 2-Microglobulin (beta 2-M) serum levels were statistically above baseline 24-96 h after rHuIFN-beta, and from the 24th to the 120th h with Frone. Both IFNs provoked a rise in intracellular 2',5'-adenylate (2-5A) levels from the 10th to the 48th h, as well as in Hu-Mx synthesis, which was significant from the 10th to the 96th h. Serum levels of 2-5A, interleukin-1 alpha (IL-1 alpha), and interleukin-1 beta (IL-1 beta) remained unchanged. There were no statistical differences in the changes provoked by the two differently derived IFN-beta in any of the biological parameters studied. Overall, the results of this study indicate that rHuIFN-beta and Frone have similar pharmacodynamics.

[Diagnostic imaging of Budd-Chiari syndrome in adults and children]. / Diagnostica per immagini della sindrome di Budd-Chiari nell'adulto e nel bambino.

Budd-Chiari syndrome is caused by the obstruction of the hepatic veins or of the inferior vena cava. It is characterized by the classic symptomatological triad: ascites, hepatomegaly, and abdominal pain. In 2/3 cases its etiology remains unknown. Budd-Chiari syndrome may be associated with polycythemia vera, neoplasms, chronic leukemia, congenital abnormalities, hypercoagulation conditions, pregnancy, oral contraceptives, and constrictive pericarditis. Even though its clinical diagnosis is difficult, radiology plays a decisive role with US, CT, MR imaging and, above all, angiography; the latter, together with liver biopsy, generally provides with an unquestionable diagnosis. Through the definition of stage of the disease, of level (intrahepatic, venous, caval, cardiac), of type (intrinsic or extrinsic), and degree of both obstruction and consequent development of collateral channels, radiology determines which patients should undergo a medical or a surgical treatment. In some case, percutaneous angioplasty can be performed. Four cases of Budd-Chiari syndrome, including two children, were investigated with US, CT, angiography, and liver biopsy; MR imaging was also employed in one case. The underlying cause was identified in 3 patients: constrictive pericarditis of probable congenital origin and web occlusion of the inferior vena cava near the right atrium in the 2 children; hepatic vein thrombosis due to essential thrombocythemia in the third case. In the fourth patient, thrombosis of the inferior vena cava and hepatic veins was unexplained. The diagnosis was established by means of liver biopsy and phlebography of the hepatic veins. Good diagnostic information was also supplied by non-invasive techniques, such as US, CT, and MR imaging.(ABSTRACT TRUNCATED AT 250 WORDS)

Styrene copolymers as pollutant adsorbents. Safe sampling volume determination.

The determination of safe sampling volumes of benzene and acetone on air samplers filled with Porapak Q, Chromosorb 101, 102 and 103 is described. Two direct methods are employed; one method is based on frontal chromatography, while the second one is a concentration method followed by thermal desorption. The results are compared to those determined by the indirect pulse chromatographic method. The safe sampling volumes determined by the direct methods were in accordance. The indirect method gives slightly different values; however, this procedure is carried out at "infinite dilution". The effect of the pollutant concentration on the safe sampling volumes was also examined. The values decrease with increasing pollutant concentration.

Chromosorb 101 as a packing material for reversed-phase chromatography.

A procedure for preparing a Chromosorb 101 liquid chromatographic column is described. Some column parameters such as the permeability, efficiency and peak asymmetry factor were calculated. The elution of some benzene and phenol derivatives from the polymeric column with different mobile phases was performed. The results showed that some gas chromatographic adsorbents such as Chromosorb 101 can be used as packings for high-performance liquid chromatographic columns. The behaviour of these styrene copolymers resembles that of a C18 silica bonded phase.

[Liquid phase chromatography for the determination of portal-injected alfadione in the general circulation. Preliminary note]. / Vromatografia in fase liquida per la determinazione nel circolo generale dell'alfadione iniettato per via portale. Nota preliminare.

The use of HPLC (High Performance Liquid Chromatography) in the quantitative determination of alfadione, which escapes liver metabolization after portal injection, is proposed. The early results are presented and possible products of metabolism are highlighted.