Bioensayo de toxicidad aguda en tres biomodelos utilizando compuestos de referencia / Acute toxicity bioassay in three biomodels using reference compounds

Los bioensayos son herramientas ampliamente utilizadas en el campo de la ecotoxicología. Como cualquier instrumento analítico, requieren ser calibrados frente a un patrón, con fines de control de calidad analítica de los organismos a utilizar en estas pruebas. Para dar cumplimiento a esta premisa se procedió a la evaluación de la toxicidad aguda de dos tóxicos de referencia en tres biomodelos representativos del ecosistema: Artemia sp., Physa cubensis y semillas de Lactuca sativa. Para determinar la toxicidad sobre los biomodelos se emplearon dos patrones: dicromato de potasio y sulfato de cobre. En ambos casos se preparó una solución madre y a partir de ella se realizaron diluciones seriadas, estableciéndose 3 réplicas por tratamiento. Para el control negativo se utilizó agua según las condiciones del hábitat de cada especie. El estudio fue realizado a temperatura y humedad controladas. Se observó para cada experimento la mortalidad como variable principal y se calculó la concentración letal media (CL50). Se apreció un decrecimiento de la mortalidad a medida que disminuyó la concentración de cada tóxico empleado. Se concluyó que el dicromato de potasio y el sulfato de cobre se pueden utilizar como patrones en la calibración de ensayos ecotoxicológicos de los biomodelos empleados

Similar to any analytical instrument, bioassays used in the field of ecotoxicology should be calibrated against a standard for analytical quality control purposes of the test organisms. To this end, the acute toxicity of two reference toxicants was evaluated in three biomodels representative of the ecosystem: Artemia sp., Physa cubensis and Lactuca sativa seeds. In the same, two patterns were used: potassium dichromate and copper sulphate. In both cases, a stock solution was prepared and serial dilutions of it, establishing 3 replicates per treatment. The control used consisted of water according to the habitat conditions of each species. The study was performed at controlled temperature and humidity. Were calculated mortality, expressed as LC50, for each experiment. A decrease in mortality was observed as the concentration of each toxicant decreased. It is concluded that potassium dichromate and copper sulphate can be used as standards in the calibration of ecotoxicological assays of the considered biomodels

Rotura del tendón del tríceps asociada a bursitis olecraniana e infiltraciones con corticoides / Triceps tendon rupture associated with olecranon bursitis and steroid injections

Se presenta un estudio anatomopatológico que demuestra la relación existente entre la rotura iterativa distal del tendón del tríceps y la historia previa de varias infiltraciones de corticoides para el tratamiento de una bursitis olecraniana, así como los resultados satisfactorios obtenidos tras la reparación primaria mediante sutura transósea en el olécranon a las 6 semanas de la rotura. El tratamiento de los tejidos inflamados con inyecciones locales de esteroides presenta riesgos, sobre todo si se hacen de forma repetida y directamente sobre el tendón, especialmente en atletas de fuerza, y por extensión en trabajadores de fuerza, quienes hacen una alta demanda de su estructura músculoesquelética

An anatomopatologic study appears that demonstrates the existing relation between the iterative distal triceps tendon rupture and the previous history of several steroid injections for the treatment of olecranon bursitis, as well as the obtained satisfactory results after the primary repair through drill holes in the olecranon to the 6 weeks of the rupture. The treatment of weaves inflamed with local steroid injections present risks, mainly if they become of repeated form and directly of the tendon, specialing in athletes of force and, by they extension in working of force, who make a high demand of their musculoesqueletic structure

Kikuchi-Fujimoto disease. A case report.

Histologically, Kikuchi-Fujimoto disease (KFD) is a necrotising, self-limiting lymphadenitis. It typically affects the lymph nodes of the neck and it is often accompanied by a high fever. The present paper documents the case of a 28-year old male carrier of KFD. From the x-ray images, the KFD clinically appeared to be a submandibular salivary gland tumor. An ultrasound study led us to believe that it was more likely a branchial cyst. Malignant lymphoma can be mistaken for KFD, thus the diagnosis must be precise and the differentiation is crucial.

[A fibroepithelial myxoid polyp of the renal pelvis in a patient with horseshoe kidneys. Apropos a case]. / Pólipo fibroepitelial mixoide de la pelvis renal en paciente con riñones en herradura. A propósito de un caso.

Tumours of the renal pelvis are usually urothelial carcinomas. The benign tumors are extremely rare. Fibroepithelial polyps are the most common mesodermal tumors of the upper urinary tract. They are found most commonly in the ureter but several have been reported in the renal pelvis. Patients usually present with pain and less commonly hematuria. Grossly, these polypoid structures are smooth nodules or filiform projections varying is size from a few millimeters to several centimetres. Histologically, they consist of a thick fibrous stalk with numerous vascular channels covered by a layer of normal or hyperplastic transitional epithelium. The etiology of these tumors is unknown but congenital, obstruction, allergy and trauma have been implicated. Conservative treatment is recommended when the diagnosis is certain. To our knowledge, this is the first report of fibroepithelial polyp of the renal pelvis in a patient with horseshoe kidney.

[Bladder paraganglioma. Report of a case and review of the Spanish literature]. / Paraganglioma vesical. Presentación de un caso y revisión de la literatura española.

Paragangliomas are rare tumours of the bladder accounting for 0.06% of all vesical tumours. This paper reports one case of vesical paraganglioma in a young female patient that has the singularity of being associated to melanin pigmentation. A review is made of cases treated in Spain, adding some comments on the signs and symptoms presented, as well as the diagnostic and therapeutical methods used in this unusual condition.

Experimental infection by Haemophilus influenzae type b in inbred mice.

The epidemiological situation of bacterial meningitis is increasing dramatically. There is no doubt that the lack of proper animal models has hampered the achievement of effective prophylactic and therapeutic means. We report the characterization of the experimental disease caused by Haemophilus influenzae type b (Hib) in mice, taking into account its importance as an etiological agent of such a type of meningitis. The high resistance of C57BL/6, CBA/ J and BALB/cJ mice to Hib infection was proven. LD50 of Hib using trypsin or iron dextran as virulence enhancement factors (VEF), both being similar and more than 1000 times lower than that without any VEF, were determined. Lesions of CNS compatible with meningitis were found in about one third of specimens. Hair bristling, conjunctivitis, diarrhea, depression and prostration were the most characteristic symptoms. The proportion of animals which die is highest on the first day, lower on the second and almost zero after 48 h of infection. Water and food intake was higher in control than in infected animals; nevertheless, there were no differences in body weight increase among the mice after 5 days post-infection. Microorganisms were isolated from CSF and blood after 6 h of infection and positive results remained according to the size of the inoculum. Despite the acuteness of the experimental disease, antibiotic treatment with internationally recommended drugs was shown to be effective. Similar results were achieved when hyperimmune serum vs. Hib was applied.

Pathologic-clinical characterization of leptospirosis in a golden Syrian hamster model.

Experimental leptospirosis was reproduced in golden Syrian hamsters (Mesocricetus aureatus). Evaluation of three Leptospira serogroups (canicola, icterohaemorrhagiae and pomona) was carried out regarding their virulence, production of symptoms and lethal activity. Macroscopic and microscopic studies of tissue lesions were also made. Animals were inoculated with 3.75 x 10(6) to 6 x 10(7) bacteria through the intraperitoneal (IP) route. The clinical development of the disease in Syrian hamsters was characterized by the presence of general symptoms between the third and fifth day after inoculation. With highly virulent strains, the distinctive clinical picture occurred and death followed before the seventh day. The strain of the pomona serogroup proved to be more virulent than those of the other serogroups and produced the most florid picture of the disease. Pathogenic aspects of this process were also studied.

Evaluation of the efficacy of human antimeningococcal immunoglobulin G in infant rats experimentally infected with Neisseria meningitidis group B.

Infants rats, a well known model for the experimental reproduction of bacterial meningitis, were used by us to test the protective potential of antibodies developed in humans who had been vaccinated with the Cuban antimeningitis vaccine (VA-MENGOCBC). Newborn rats were inoculated by the intraperitoneal and intranasal routes with suspensions of Neisseria meningitidis group B bacteria. Bacteremia kinetics were evaluated from blood and brain-spinal fluid cultures. Samples of the central nervous system were taken and smears of backbone fluids prepared for histopathologic evaluations. Characterization of bacteremia evolution, as well as the mean lethal dose of germs and histopathologic features, were determined. After standardization of the model, therapeutic schemes were applied using passive immunization pre- and post-infection with N. meningitidis. A significant level of protection was obtained in relation to control animals that received the same challenge doses.

[Amyloid arthropathy associated with multiple myeloma]. / Artropatía amiloide asociada a mieloma múltiple.

Amyloidosis as a complication of patients afflicted with multiple myeloma only arose in 15% of the cases. The articular localization is particularly rare, the clinical findings being similar to rheumatoid arthritis. A case of amyloid arthritis associated to Bence-Jones myeloma, kappa type, is presented and the literature is reviewed.

Second malignant neoplasms following childhood Hodgkin's disease: treatment and splenectomy as risk factors.

The risk of second malignant neoplasm (SMN) was evaluated in 979 children with Hodgkin's disease. This cohort was diagnosed between 1955 and 1979 at one of the institutions of the Late Effects Study Group. Solid tumors, non-lymphocytic leukemia, and non-Hodgkin's lymphoma (NHL) developed in 18, 17, and 3 patients, respectively. The estimated cumulative probability of developing any SMN was 2% at 5 years from diagnosis, 5% at 10 years, and 9% at 15 years. The incidence is ninefold greater than the risk of acquiring cancer in 19 year-olds, the median age at which the diagnosis of SMN was made in this study population. For leukemia and NHL the corresponding probabilities were 1%, 3%, and 4% for the group as a whole but were increased (2%, 6%, and 8%) in patients who had suffered one or more recurrences. In order to analyze the risk of leukemia and NHL associated with alkylating agent chemotherapy, each patient was assigned a score of one for each alkylating agent administered for a 6-month period. Scores of 2, 4, 6, and 8 were associated with probabilities of leukemia or NHL of 2%, 3%, 6%, and 10%, respectively. In a multivariate analysis for leukemia/lymphoma that included AAD score, stage, and splenectomy, the effect of AAD score and splenectomy did not change substantially compared to the univariate results. AAD score remained statistically significant (P = .0001), and splenectomy was of borderline significance (P = .09). Of the 18 solid tumor SMNs, 15 developed within the field of radiation, and one other developed in tissue irradiated 34 years earlier for hemangioma. This study of a large and unselected group of children with Hodgkin's disease who received a variety of therapies demonstrates that children are as likely as adults to develop acute leukemia after alkylating agents and solid tumors in the field of radiation therapy.

Educational late effects in long-term survivors of childhood acute lymphocytic leukemia.

Records of levels of school achievement in long-term survivors of childhood acute lymphocytic leukemia were obtained for 23 children who had received 2,400-rad cranial irradiation and intrathecal methotrexate and standard chemotherapeutic agents 8 to 10 years previously. The children had been evaluated with standardized tests of intelligence at the time of diagnosis and periodically thereafter. Declines in IQ and cognitive dysfunctions have been previously described. School placements, educational histories, attendance records, learning strengths and weaknesses, social/emotional adjustments, and grade level achievements in reading and mathematics as measured by standardized achievement tests are reported here. Children achieved less than the expected levels in both reading and mathematics given both pretreatment and most recent IQ scores. Neither sex nor initial IQ were related to achievement scores. Children experienced difficulty with attention/concentration, memory, sequencing, and comprehension when performing school tasks. Individual children showed different degrees of dysfunction, but results of this study suggest that there are patterns of specific learning disabilities rather than global retardation. A small number of children achieved greater than expected levels, indicating that individualized instruction, tutoring, and parental support may reduce some learning deficits. Early educational intervention is recommended for similarly treated patients.

Gestational risk factors for Wilms' tumor: results of a case-control study.

Gestational risk factors for Wilms' tumor were investigated in a pair-matched case-control study. Cases who were under 15 years of age at diagnosis during 1970-1983 were identified through the registries of the three main hospitals treating childhood cancer in the greater Philadelphia area. Controls were selected by random digit dialing and were matched to cases on race, birth date, and telephone area code and exchange. Because of a low participation rate among nonwhites, results are reported only for the 88 white matched pairs whose parents were interviewed by telephone. Of the hypothesized risk factors, maternal use of hair-coloring products in the year prior to the index child's birth (odds ratio, 3.6; P = 0.003) and hypertension or fluid retention during pregnancy (odds ratio, 5.0, P = 0.01) were significantly associated with increased risk of Wilms' tumor. Use of hair-coloring products was strongly associated with cases in which Wilms' tumor was diagnosed before 2 years of age (odds ratio, 15; P = 0.001). For two other gestational factors, tea drinking and vaginal infection, the odds ratios were significantly elevated for all cases and the effects were concentrated among the nongenetic cases. Bilateral cases had a significantly higher mean birth weight than did their controls. Older maternal age was significantly associated with the genetic form of Wilms' tumor. Adjustment for possible confounders and consideration of the time interval between the index pregnancy and the interview did not substantially alter the findings.

Discriminating power of measurements from maximum expiratory flow-volume curves.

Maximum expiratory flow-volume curves have been used to characterize normal and abnormal respiratory function. Previous investigators have usually attempted to study whether any single lung function separately is most useful in characterizing lung dysfunction. Using stepwise discriminant analysis we sought to identify which combination of lung function parameters derived from maximum expiratory flow-volume curves could best discriminate between epidemiologic groups defined on the basis of smoking status and presence or absence of respiratory symptoms. We studied 5,031 whites, 2,271 males and 2,760 females, from three communities. In general, combinations of lung functions were no more useful than single lung functions to best discriminate between the groups studied. Flow rates at 50 and 25% of vital capacity remaining to be expired were most often selected as the best discriminating lung function, possibly suggesting obstruction of small airways in the smoking and symptomatic groups.