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F Antillón

Publications and source records attributed to F Antillón.

At least 19 recordsLinked to original sources

Effect of storage temperatures on growth and survival of Escherichia coli O157: H7 inoculated in foods from a neotropical environment.

Escherichia coli O157: H7 has emerged as a new pathogen and is found worldwide. We studied the effect of several storage temperatures on the survival of this bacterium in common foods from a neotropical environment (Costa Rica) because at least seven clinical cases have been reported from the country, and no epidemiological link or probable food association has been described. High (10(6)-10(8) CFU/ml) and low (10(4)-10(6) CFU/ml) populations of E. coli were inoculated (three replications) in ground meat, chopped cabbage, chicken giblets and pasteurized milk and incubated at 0, 6 and 12 degrees C for 24, 48 and 72 h. Vegetables and milk were also stored at 22 degrees C for the same periods. The E. coli O157: H7 enumeration was done according to the methodology described in the Bacteriological Analytical Manual. Populations of E. coli O157: H7 showed either an increasing or decreasing trend, according to temperature, time or food base. Our data indicate that E. coli O157: H7 is capable of surviving and growing in meat, cabbage, milk and chicken giblets; food items commonly consumed by Costa Ricans.

Animals↗

Microbiological contamination of enteral feeding solutions used in Costa Rican hospitals.

Enteral feeding is the most common and preferred modality for providing nutritional support to hospital patients with a functional gastrointestinal tract that can not satisfy their nutritional requirements. Nevertheless, enteral feeding may be an important cause of bacterial infection. The aim of this study was to evaluate the microbial contamination level of enteral feedings distributed in Costa Rican hospitals. A total of 124 samples of enteral feeding, coming from five different hospitals from San José, Costa Rica, were evaluated during the second semester of 1997 and first of 1998 for the presence and identification of total and fecal coliforms, Pseudomonas sp. and Listeria sp. A subpopulation of the Pseudomonas isolated was analyzed for their antibiotic susceptibility patterns. The concentration of Gram negative rods in the samples of enteral feeding solutions ranged from 10(3) to 10(7) CFU/mL, markedly exceeding the permissible level (10(2) CFU/mL or less). The coliforms most frequently isolated included Enterobacter cloacae, Escherichia coil, Serratia sp. and Klebsiella pnuemoniae, Pseudomonas sp. was isolated in more than 70% of the samples made from commercial based solutions, fruits and vegetables. P. aeruginosa and P. fluorescens were the species most frequently isolated. Listeria sp. was not isolated from enteral solutions samples. The results obtained demonstrate that it is urgent to assure strict hygiene during the preparation and handling of all enteral feed in order to avoid bacterial growth. The implementation of HACCP (Hazard Analysis and Critical Control Points) system will be required in a near future for better quality control of enteral nutrition mixtures.

Costa Rica↗

5q- in a child with refractory anemia with excess blasts: similarities to 5q- syndrome in adults.

A 19-month-old boy was referred to our institution because of chronic macrocytic anemia and severe thrombocytopenia. At age 17 months, he had developed petechiae. He had a leukocyte count of 4.4 x 10(9)/L, hemoglobin concentration of 7.9 g/dL, packed cell volume of 21%, mean corpuscular volume of 101 fL, and platelet count of 19 x 10(9)/L. At the time of referral, a bone marrow aspirate and biopsy revealed myelodysplastic changes that included megakaryocytic hyperplasia with hypolobated megakaryocytes, megaloblastoid erythropoiesis, 12% blast cells, and bone marrow fibrosis; the diagnosis was refractory anemia with excess blasts (RAEB). Cytogenetic analysis showed the following abnormalities: 47, XY, inv(3)(p21q25), del(5)(q22q31), +21/46, XY. By dinucleotide polymorphism analysis, the 5q22-q31 loci were normal in peripheral blood granulocytes. Because of severe thrombocytopenia that became refractory to platelet transfusions and because of possible progression to leukemia, the patient received an unrelated-donor bone marrow transplant. Recovery was complicated by a visceral fungal infection, but the patient now has normal, fully reconstituted bone marrow function. This patient is the youngest to be reported with RAEB and a 5q- anomaly accompanied by thrombocytopenia, megakaryocytic hyperplasia with hypolobated megakaryocytes, and macrocytic anemia with megaloblastoid erythropoiesis, similar to "5q- syndrome" in adults.

Anemia, Refractory↗

[Microwave effect on survival of sporulated bacteria inoculated in minced meat].

Due to the current tendency of cooking and heating meat prepared foods in microwave ovens and the possibility that they transmit bacterial diseases, the survival rate of spore-forming bacteria was evaluated in minced meat samples. Meat was innoculated with a known number of Bacillus cereus and Clostridium perfringens spores, and laterly thawed and cooked in an Amana microwave oven (2450 Hz). Survival rate was determined according to the methodology described by Vanderzant & Splittstoesser, and the activity of the enzyme acid phosphatase was determined as cooking parameter. B. cereus spore showed a decrease in its number as the time of exposition increased, but without fully disappearing. C. perfringens spores also decreased in number, but showed a later increase, associated with the germination of survival spores.

Bacillus cereus↗

[Effect of microwaves over Staphylococcus aureus and Salmonella spp. inoculated into frozen minced meat].

The efficacy of the microwave oven in the destruction of some pathogenic microorganisms inoculated into minced meat was studied. These were inoculated with Salmonella spp. or Staphylococcus aureus, freezed for 2-3 days at -4 degrees C and thawed, according to their weight, in an Amana microwave (24450 Hz). They were radiated at levels of 60%, 70%, 80% and 90% for periods of 15, 45, 60, 90 and 105 seconds. The rate of survival of each bacteria was determined according to the methodology described by Vanderzant and Splittstoesser, as well as the activity of the acid phosphate enzyme as cooking parameter. The microbiological analysis shows that, despite the cooking level used, the time required for the elimination of both bacteria is greater than the one in which the meat is considered enzymatically and organoleptically cooked.

Acid Phosphatase↗

[Microbiologic depuration of Anadara tuberculosa (Mollusca: Arcidae)].

In Costa Rica the mollusk Anadara tuberculosa represents a risk for human health due to the contamination of the growing waters and the fact that its is consumed raw. The families depending on the income obtained through commercialization of these animals have a low education and economic status. Therefore, it is of great importance to develop and evaluate simple methods of depuration that could be easily used by these families to make these mollusks safe for consumption. Bottles containing 11 of saline solution (25g/l) were prepared in duplicates to test the bactericidal effect of acetic acid. The solution in each bottle was adjusted to ph 4.5, 5.0 or 5.5 or held at ph of 7.0 or 8.0 for the controls. The solution in each bottle was then inoculated with approximately 1 X 104 cfu/ml of coliforms. Counts of coliforms were determined for each bottle 0, 1, 2, 4 and 8 hours after inoculation. For the depuration studies, specimens with diameters ranging from 4.0 to 4.5 cm were collected from a harvester at the estuary of Puntarenas, Gulf of Nicoya. Fifty specimens each were depurated in separate tanks containing 25 1 of oxygenated saline solution adjusted with acetic acid to an initial ph of 4.5 (treatment) or non adjusted ph of 8.0 (control). Counts of Enterobacteriaceae were determined, in duplicates, every 12 hr for 48 hr. An additional fifty animals were depurated using the defined method and tested to determine if they met international standards of microbiological quality for aerobic plate count, Enterobacteriaceae count, Escherichia coli count and presence of Salmonella. A sensory evaluation using a triangle test was performed to compare a typical dish prepared with depurated or non-depurated animals. A significant coliform reduction was determined in a saline solution (25 g/l) at a pH range of 4.5 to 5.5. This reduction, during 8 hr, was higher in the acid treatments compared to the controls. During depuration, the elimination of Enterobacteriaceae bacteria was faster when acetic was used (initial ph = 4.5) than when it was not. This elimination was more important the first 24 hr, time defined as adequate for the application of the method. The method has the advantage of transforming the bivalve in a product that is safe for human consumption, since it guarantees that the international standards of microbiological quality, for raw and depurated mollusks, are reached. On the other hand, the sensory qualities of a typical dish prepared with depurated animals are not affected by the method, which can be easily implemented and applied by the people that work in the extraction of this mollusk.

Acetic Acid↗

[Microbiological quality of street sold fruits in San José, Costa Rica].

The sanitary quality of street sold fruits was analyzed during the period from march 1990 thru march 1993 in San Jose, Costa Rica. It looked for the presence of Salmonella spp. Shigella spp., Escherichia coli as well as fecal coliforms in natural refreshments, fruit salads and the fruits most frecuently expended on streets, either in slices as the pineapple (Ananas comosus), papaya (Carica papaya), non-ripe mangoe (Mangifera indica) and watermelon (Citrullus vulgaris) and those that can be eaten without peeling, like nances (Byrsonima crassifolia) and jocotes (Spondias purpurea). 25 samples of each fruit, 50 natural refreshments and 50 fruit salads were processed according to rinse solution method, and the bacteriological determination was based in the methodology described by Vanderzant & Splittstoesser and the Bacteriological Analytical Manual. In the same way, it was used the Most Probable Number for 5 tubes described in the Standar Methods of Water and Wastewater in orden to analyze 15 samples of ready to use water by the fruit hawker. The nutritional value was studied according to the food composition tables for Costa Rica, Latin America and USA. The results show that more than 30% of fruit samples, 70% of natural refreshments and 96% of fruit salad presented fecal coliforms. Same time, all of them present important contamination indexes with E. coli. Salmonella spp. and Shigella spp. were not isolated. The water analysis revelead that 53% contained fecal coliforms, probably due to the lack of hygiene in the utensils used to collect water. The nutritional evaluation shows that fruit portions (except watermelon) satisfy more than 100% of the diary recommendation of vitamin C (60 mg) and 4-7% of the recommended ingestion of dietetic fiber (30g).

Costa Rica↗

[Sanitary quality of some food distributed by hospital food services of Costa Rica].

The sanitary quality of 100 samples of salad and 100 samples of skinless fruits distributed by the Hospital Food Services were studied. Samples were processed according to rinse solution method, and the bacteriological determination was based in the methodology described by Vanderzant & Splittstoesser. The preparation scheme of each product was realized in order to analyze risks and determine the critical control points according to ICMSF (International Commission on Microbiological Specifications for Foods). Microbiological studies on the critical control points (total and fecal coliforms determinations) were done according to the surface analysis using the swab contact method as described by Vanderzant & Splittstoesser. Our results show that 93% of the salads and 65% of the fruits presented contamination of fecal origin. The hands of the operators and kitchen utensils also presented important fecal contamination indexes.

Costa Rica↗

[Role of conservative surgery in the multidisciplinary treatment of Ewing's sarcoma in childhood].

BACKGROUND: In order to cure Ewing's sarcoma it is necessary to have an approach which considers the radical local control on the sites of macroscopic disease, along with the systemic control of micrometastases. On the present study the experience of the authors in analyzed, remarking the role of cytoreduction surgery on curability. METHODS: From January 1982 to August 1991, 24 patients with the mean age 13 years, 14 boys and 10 girls, previously untreated and with a pathology proven diagnosis have been treated by the authors. The treatment protocol included: alternating chemotherapy with cyclophosphamide, adriamycin, methotrexate, bleomycin, actinomycin D and vincristine; administered simultaneously with preoperative external radiation with a volume that completely included the affected bone and surrounding soft tissues for a total dose of 45 Gy/4.5 weeks. After a resting period of 4 weeks, resection of the involved bone and adjacent healthy bone was performed, followed by a single dose of 10-15 Gy of intraoperative radiotherapy to the tumor bed. Subsequently a custom prostheses or allograft was implanted. RESULTS: Twenty patients had localized disease and 4 had metastatic disease at diagnosis. In 16 cases the tumor was in extremities, 5 axial, and 3 extraskeletical. In 15 patients surgery with limb sparing techniques was performed, 8 had en block resection and one amputation (calcaneous location). At the time of this report 21 patient are alive (87%). Four had disease progression, of this 3 had died (12%). The actuarial disease free survival rate is 80% +/- 9% with a follow-up of 104 months, being the mean survival time of 85.5 months. CONCLUSIONS: The cytoreduction surgery included into a multidisciplinary approach permits to achieve a high rate of cure in Ewing's sarcoma. The toxicity of the program can be considered acceptable.

Actuarial Analysis↗

[Isolation of Vibrio cholerae no-01 in the Gulf of Nicoya, Costa Rica].

In a bacteriological study on samples of bivalves, mud and surface waters from the Gulf of Nicoya, Costa Rica, 18 strains of non-01 Vibrio cholerae and 50 of V. mimicus were isolated. The samples were enriched in alkaline peptone water, and streaked on MacConkey and inositol-brilliant green bile agars. Biochemical and serological tests were used for their identification. Both species were isolated from all sampling sites (Lepanto, Jicaral and Puntarenas) with either of the two agar media, even though these were not specific for vibrios.

Agar↗

[Isolation of enteropathogenic Vibrio in bivalves and mud from the Nicoya Gulf, Costa Rica].

The presence of enteropathogenic Vibrio was evaluated in 36 sediment samples and 41 bivalve samples obtained from 3 collecting sites in the Golfo de Nicoya, Costa Rica. Isolation methods for halophilic and non halophilic Vibrio were used. The biochemical profiles of the strains obtained revealed the presence of the following isolates: 224 Vibrio parahaemolyticus, 3 V. furnissii, 1 V. damsela and 3 V. fluvialis. V. cholerae was not isolated, due principally to the use of TCBS agar.

Animals↗

[Intraoperative radiotherapy in the multidisciplinary treatment of malignant tumors in children. Preliminary results].

From September 1984 to March 1989, 57 children received intraoperative radiotherapy as part of a multidisciplinary tumor treatment. Their age ranged from 2 to 18 years. Tumor types: osteosarcoma, 21; Ewing's sarcoma, 19; soft tissue sarcomas, 6; neuroblastoma, 5; Wilm's tumor, 3; Hodgkin, 1; glioma, 1, and malignant pheochromocytoma, 1. In 44 patients the disease was localized while 13 had distant metastases. Intraoperative radiotherapy was used in 48 previously untreated patients as part of a radical treatment program and in 9 cases as an effort to rescue local failures (5 in previously irradiated areas). The intraoperative radiation field included the surgically exposed tumor or tumor bed, and the single doses ranged from 10 to 20 Gy, with 6-20 MeV electrons. With a median follow up time of 25 months (4 to 51 + months) 44 out of 57 patients are alive without local recurrence and 13 have died from tumor (6 with local progression). Intraoperative radiotherapy seems to be a feasible treatment which might promote local control in pediatric tumors.

Adolescent↗

[Aeromonas spp. and Plesiomonas shigelloides in bivalves, mud, and water from the Gulf of Nicoya, Costa Rica].

Bivalves, mud, and surface water were collected at three different sites of the Gulf of Nicoya, Costa Rica, in search of Aeromonas spp. and Plesiomonas shigelloides. For their isolation, these bacteria were enriched in alkaline peptone water and streaked on MacConkey agar and on brilliant green bile inositol agar. This was followed by the biochemical tests necessary for their identification. Thirty-five strains of A. hydrophila, 58 of A. caviae, 43 of A. sobria, and 7 of P. shigelloides were isolated. None of these predominated nor was there any indication of a seasonal distribution along the 15 month's duration of the study. Seven strains of A. hydrophila and two of A. sobria showed the biochemical characteristics associated with toxin production (positive Voges-Proskauer and lysine decarboxylase tests). These species are widely distributed in the gulf and there is risk of contracting an infection while bathing or when eating raw bivalves from this area.

Aeromonas↗

Genetic and cytogenetic studies in children with retinoblastoma.

Genetic and cytogenetic studies were performed in 110 children with retinoblastoma (57 girls and 53 boys), with 70% of cases being unilateral and 30% bilateral. The mean age of the patients at diagnosis was 22.6 months in unilateral and 11.1 months in bilateral cases. Sporadic cases were 94.5%, and the remaining were familial. There was no difference when the paternal age of sporadic cases was compared with that of familial cases. Three patients from a family exhibiting unilateral retinoblastoma had an interstitial deletion at band 13q14. The presence of other neoplasms and the importance of the genetic and chromosomic studies, for the purpose of genetic counseling, are discussed.

Child, Preschool↗