Modulación de la fisiología gastrointestinal mediante cepas probióticas de Lactobacillus casei y Bifidobacterium bifidum / Modulation of gastrointestinal physiology through probiotic strains of Lactobacillus casei and Bifidobacterium bifidum

En el contexto de la alimentación y la promoción de la salud se sitúan los productos denominados alimentos funcionales que tienen diversos efectos beneficiosos en el organismo, además de los meramente nutricionales. Dentro de estos alimentos funcionales, entre otros, podemos distinguir entre compuestos probióticos y prebióticos. Los microorganismos más utilizados en alimentos probióticos pertenecen a los géneros Lactobacillus y Bifidobacterium. En el presente trabajo se ha estudiado el efecto de dietas suplementadas con Lactobacillus casei o Bifidobacterium bifidum en el desarrollo animal y en especial sobre la función intestinal, centrada en su actividad immunitaria, digestiva y absortiva de animales en crecimiento. Las cepas bacterianas utilizadas modifican la actividad del intestino delgado de los ratones sanos, afectando significativamente a su actividad enzimática (sacarasa, maltasa y aminopeptidasa) y a la captación de nutrientes (galactosa y glicilsarcosina), así como a la actividad inmune intestinal (mayor número de placas de Peyer). Sin embargo, estos efectos no parecen perturbar el desarrollo de los animales en crecimiento ya que no se aprecian diferencias significativas en su peso corporal ni en sus parámetros sanguíneos. Estos resultados ponen de manifiesto los posibles efectos beneficiosos en la fisiología intestinal y contribuyen al conocimiento de los posibles mecanismos de acción de los probióticos, que se pudieran utilizar en el tratamiento preventivo de diferentes patologías relacionadas con el aparato digestivo

The products called functional foods, which besides being merely nutritional have different beneficial effects on the organism, are situated in the context of diet and health promotion. Amongst these functional foods we can distinguish, amongst others, between probiotic and prebiotic compounds. The microorganisms most widely used in probiotic foods belong to the Lactobacillus and Bifidobacterium types. In this article we have studied the effect of diets supplemented with Lactobacillus casei or Bifidobacterium bifidum on animal development and especially on the intestinal function, centred on their immune, digestive and absorptive activity in growing animals. The bacteria strains used modify the activity of the small intestine of healthy mice, significantly affecting their enzymatic activity (sucrase, maltase and aminopeptidase) and the collection of nutrients (galactose and glycilsarcosine), as well as the intestinal immune activity (higher number of Peyer’s patches). However, these effects do not appear to disturb the development of the growing animals since no significant differences are appreciated in their body weight or in their blood parameters. These results make clear the possible beneficial effects on intestinal physiology and contribute to the understanding of the possible mechanisms of action of the probiotics, which could be employed in the preventive treatment of different pathologies related to the digestive apparatus

Effect of dietary quercetin and sphingomyelin on intestinal nutrient absorption and animal growth.

Research on cancer and other conditions has shown flavonoids and sphingolipids to be food components capable of exerting chemoprotective action. Nevertheless, little is known about their effects on healthy individuals and their potential usefulness as therapeutic agents. The present study examined the possible action of a dietary flavonoid, quercetin, and a sphingolipid, sphingomyelin, as functional foods in healthy animals. In particular, the effect on animal growth of supplementing a conventional diet with one or other of these substances (0.5 % quercetin and 0.05 % sphingomyelin) was considered. Possible action affecting intestinal physiology was also analysed by measuring the uptake of sugar and dipeptide, mediated by the Na(+)-dependent sugar transporter SGLT1 and the dipeptide Na(+)/H(+) exchanger PEPT1 respectively, and the activity of related intestinal enzymes such as sucrase, maltase and aminopeptidase N. Both substances seemed to modify small intestinal activity in healthy mice, altering intestinal enzymatic activity and nutrient uptake. These effects observed in the small intestine did not impair normal development of the animals, as no differences in serum biochemical parameters or in organ and body weights were found. The findings should help in elucidating the mechanisms of action of these food components with a view to their possible use in the prevention of certain pathological conditions.

[Modulation of gastrointestinal physiology through probiotic strains of Lactobacillus casei and Bifidobacterium bifidum]. / Modulación de la fisiología gastrointestinal mediante cepas probióticas de Lactobacillus casei y Bifidobacterium bifidum.

The products called functional foods, which besides being merely nutritional have different beneficial effects on the organism, are situated in the context of diet and health promotion. Amongst these functional foods we can distinguish, amongst others, between probiotic and prebiotic compounds. The micro-organisms most widely used in probiotic foods belong to the Lactobacillus and Bifidobacterium types. In this article we have studied the effect of diets supplemented with Lactobacillus casei or Bifidobacterium bifidum on animal development and especially on the intestinal function, centred on their immune, digestive and absorptive activity in growing animals. The bacteria strains used modify the activity of the small intestine of healthy mice, significantly affecting their enzymatic activity (sucrase, maltase and aminopeptidase) and the collection of nutrients (galactose and glycilsarcosine), as well as the intestinal immune activity (higher number of Peyer's patches). However, these effects do not appear to disturb the development of the growing animals since no significant differences are appreciated in their body weight or in their blood parameters. These results make clear the possible beneficial effects on intestinal physiology and contribute to the understanding of the possible mechanisms of action of the probiotics, which could be employed in the preventive treatment of different pathologies related to the digestive apparatus.

Biphenotypic acute leukemia with t(15;17).

Biphenotypic acute leukemias (BAL) represent 5% of all acute leukemias. The most frequent cytogenetic abnormalities described are Philadelphia chromosome and 11q23 involvement. Here we report a BAL case, with blasts showing lymphoblast morphology and positivity for myeloperoxidase (in 6% of the blast cells). Immunophenotype revealed the compromise of myeloid and B-lymphoid lineages. Cytogenetic analysis showed the t(15;17) and 8 trisomy. PML/RARa rearrangement was detected by fluorescent in situ hybridization (FISH) on interphase nuclei while PML/RARa fusion transcript was detected in the bone marrow and peripheral blood by molecular biology studies (RT-PCR). This report describes a BAL case with an unfrequent cytogenetic abnormality, and highlights the importance of correlating the results of multiple diagnostic methods in order to establish a correct diagnosis and treatment in BAL patients.

Randomized trial of CVPP for three versus six cycles in favorable-prognosis and CVPP versus AOPE plus radiotherapy in intermediate-prognosis untreated Hodgkin's disease.

PURPOSE: To evaluate in a randomized trial the impact of three versus six cycles of cyclophosphamide, vinblastine, procarbazine, and prednisone (CVPP) chemotherapy in favorable-prognosis and CVPP versus doxorubicin, vincristine, prednisone, and etoposide (AOPE) plus involved-field radiotherapy (RT) in intermediate-prognosis previously untreated Hodgkin's disease. PATIENTS AND METHODS: Of 256 patients evaluated, 80 with a favorable prognosis according to a prognostic index designed by the Grupo Argentina de Tratamiento de Leucemia Aguda (GATLA) were randomized to three versus six cycles of CVPP without RT and 176 with intermediate risk to CVPP versus AOPE, both for six cycles with RT between the third and fourth cycles of 30 Gy to the involved areas at diagnosis. CVPP consisted of intravenous (I.V.) cyclophosphamide and vinblastine on days 1 and 8, and oral procarbazine and prednisone on days 1 to 14, every 28 days. AOPE consisted of I.V. doxorubicin and vincristine on day 1, oral prednisone on days 1 to 5, and I.V. etoposide on days 1 and 3, every 28 days. RESULTS: Complete remission was obtained in 39 of 41 (95%) patients treated with three cycles of CVPP and 36 of 39 (92%) treated with six cycles in the favorable-risk group (difference not significant [NS]). In the intermediate-risk group, 89 of 92 (97%) treated with CVPP plus RT versus 75 of 84 (89%) treated with AOPE plus RT achieved a complete remission (P = .05). At 60 months, the event-free survival (EFS) and overall survival rates in the favorable-risk group were 80% and 91% for CVPP x 3 and 84% and 97% for CVPP x 6, respectively (P = NS). In the intermediate-risk group, 60-month EFS rate for CVPP plus RT was 85%, compared with 66% for AOPE plus RT (P = .009). The overall survival rate was 95% versus 87% respectively (P = .157). CONCLUSION: Three cycles of CVPP without RT are equally effective as six cycles in the favorable-risk group. However, in the intermediate-group, CVPP plus RT is superior to AOPE plus RT, with significantly fewer events before and after induction (P = .009), without a difference in overall survival.

Results of treatment with an intensive combination induction regimen containing idarubicin in children with acute myeloblastic leukemia: preliminary report of the Argentine Group for Treatment of Acute Leukemia.

In April 1990, the Argentine Group for Treatment of Acute Leukemia began a multicenter trial for the treatment of previously untreated acute myeloblastic leukemia patients who were under 21 years of age. Initial treatment consisted of an 8-day induction phase with cytarabine together with idarubicin on days 3 to 5 and etoposide on days 6 to 8. A multidrug consolidation phase was subsequently administered and, after a treatment-free interval of 2 to 4 weeks, two 5-day intensification courses with high-dose cytarabine and etoposide were delivered with a 4-week interval between each course. Continuation therapy was started 2 to 4 weeks after the second course, with 6-thioguanine daily and cytarabine daily for 4 days every 4 weeks. Treatment was stopped after 18 months in children in continuous complete remission. A preliminary evaluation of this ongoing study included 36 patients with a mean age of 7.5 years (age range, 5 months to 16 years). The majority of patients had a French-American-British classification of M2 (n = 13) or M4 (n = 8). Complete remission was achieved by 91.7% of patients, while one died from sepsis in bone marrow hypoplasia and two were regarded as treatment failures. At a median follow-up of 12 months (range, 2 to 23 months) there were 12 adverse events: six bone marrow relapses, one bone marrow/skin relapse, and five deaths in complete remission (all deaths occurred during the consolidation phase). During the induction phase most of the patients experienced prolonged myelosuppression, and grade 3 to 4 toxicity (according to the Children's Cancer Group criteria) was frequently seen. Alopecia was universal. However, toxicity was manageable. We conclude that idarubicin in combination with cytarabine and etoposide is a highly effective regimen for induction in children with acute myeloblastic leukemia.