[Lumbar plexus nerve block provides better analgesic management than periarticular infiltration in primary total hip arthroplasty. Comparative, prospective, and single-blind clinical trial]. / El bloqueo nervioso del plexo lumbar proporciona un mejor manejo analgésico que la infiltración periarticular en artroplastía total primaria de cadera. Ensayo clínico comparativo, prospectivo y simple ciego.

INTRODUCTION: joint replacement is a highly effective intervention that significantly improves the patient's quality of life, relieves symptoms, restores joint function, and improves mobility and independence. The optimal pain control after total hip replacement has become an important goal of postoperative management. The purpose of this paper is to compare periarticular infiltration (PAI) and lumbar plexus nerve block (LPNB) for the management of post-operative pain in primary total hip arthroplasty because we believe that LPNB provides better analgesic management and lower opioid consumption. We evaluated the opioid usage during hospitalization and the complications derived from either technique. MATERIAL AND METHODS: we randomized 45 patients who underwent elective total hip arthroplasty between January 2019 and January 2020. Two groups were evaluated based on the association of PAI or LPNB. Both as part of a multimodal analgesic regimen. RESULTS: a total of 45 patients were evaluated (22 PAI group, 23 LPNB group). Block group required less opioid administration (p = 0.069). Most of the patients in both groups reported mild/moderate pain. The LPNB group had lower pain scale with physiotherapy. We did not have complications derived from either technique. CONCLUSION: lumbar plexus nerve block (LPNB) in patients undergoing total hip arthroplasty provides better pain management and reduced opioid consumption compared to PAI. The performance of this technique does not delay the beginning of physiotherapy and there were not any issues with the patient's recovery.

INTRODUCCIÓN: la artroplastía es una intervención altamente eficaz que mejora de manera significativa la calidad de vida del paciente, alivia los síntomas, restaura la función articular y mejora la movilidad e independencia. El control óptimo del dolor después de la artroplastía total de cadera se ha convertido en un objetivo importante del tratamiento postoperatorio. El propósito de este trabajo es comparar la infiltración periarticular (IPA) y el bloqueo nervioso del plexo lumbar (BNPL) para el manejo del dolor postoperatorio en la artroplastía total de cadera primaria, ya que creemos que la BNPL proporciona mejor manejo analgésico y menor consumo de opioides. Se evaluó el uso de opioides durante la hospitalización y las complicaciones derivadas de cada técnica. MATERIAL Y MÉTODOS: fueron aleatorizados 45 pacientes tratados con artroplastía total de cadera electiva entre Enero de 2019 y Enero de 2020 en dos grupos: IPA o BNPL. Ambos como parte de un régimen analgésico multimodal. RESULTADOS: veintidós en el grupo IPA y 23 en el grupo BNPL. El grupo de bloqueo requirió menos administración de opioides (p = 0.069). La mayoría de los pacientes de ambos grupos reportaron dolor leve/moderado. El grupo de BNPL tuvo menor escala de dolor al realizar fisioterapia. No tuvimos complicaciones derivadas de ninguna de las técnicas analgésicas. CONCLUSIÓN: el BNPL en pacientes sometidos a artroplastía total de cadera proporciona mejor manejo del dolor y una reducción del consumo de opioides en el postoperatorio en comparación con la IPA. La realización de esta técnica no retrasa el inicio de la fisioterapia y no hubo problemas con la recuperación del paciente.

[Continuous vs. intermitent intravenous analgesia for primary total knee replacement: analysis of the quality of the pain control, hospital stay and costs]. / Analgesia endovenosa continua versus analgesia endovenosa intermitente para reemplazo total de rodilla primario: análisis de la calidad analgésica, tiempo de hospitalización y costos económicos.

BACKGROUND: The International Association for the Study of Pain (IASP) defines pain as an unpleasant sensory and emotional experience associated with actual or potential tissue damage. Total knee arthroplasty is one of the orthopedic surgeries that manifests more pain in the first 24-48 hours, needing a multimodal analgesic therapy. The objective of this work is to compare two different intravenous analgesic modes applied to patients undergoing a primary total knee arthroplasty, analyzing the quality of pain control, hospital stay and costs. MATERIAL AND METHODS: Simple blind, comparative and prospective study comprised of 42 patients operated of total knee arthroplasty secondary to degenerative arthritis in the period between May 2016 and May 2017. RESULTS: The distribution of pain showed significant differences (p 0.0401) between both groups, indicating that the application of continuous pump for analgesia controls this symptom early. The hospital stay, on average, was different in the groups (p = 0.001), estimating about 15 hours less following the use of continuous pump. This strategy is globally more economic. DISCUSSION: The continuous infusion pump of analgesia compared with intermittent formal intravenous regimen showed better control of pain, decreasing the perception of pain by the patient, bettering the tolerance to physical therapy and reducing, on average, 15 hours of hospital stay, and thus, the final costs of the surgery.

INTRODUCCIÓN: La Asociación Internacional para el Estudio del Dolor (IASP, por sus siglas en inglés) define el dolor como una experiencia sensorial y emocional desagradable asociada a un daño tisular real o potencial. La artroplastía total de rodilla es una de las cirugías ortopédicas que cursa con más dolor en las primeras 24-48 horas, por lo que precisa de una terapia multimodal de analgesia. El objetivo de este trabajo es comparar dos modos analgésicos endovenosos diferentes aplicados a pacientes sometidos a cirugía de artroplastía total de rodilla primaria, analizando la calidad analgésica, el tiempo de hospitalización y los costos económicos. MATERIAL Y MÉTODOS: Estudio prospectivo, comparativo y simple ciego conformado por 42 pacientes intervenidos quirúrgicamente de artroplastía total de rodilla secundaria a artrosis degenerativa en el período comprendido entre Mayo de 2016 y Mayo de 2017. RESULTADOS: La distribución del dolor mostró diferencias significativas (p 0.0401) entre ambos grupos, indicando que la aplicación de analgesia mediante bomba continua controla este síntoma de manera temprana. El tiempo de hospitalización promedio fue diferente en los grupos (p = 0.001); se estimaron alrededor de 15 horas menos siguiendo el protocolo de bomba continua. Además, esta estrategia es globalmente más económica. CONCLUSIÓN: La bomba de infusión continua de analgesia compara da con la analgesia endovenosa reglada intermitente logró un mejor control del dolor, disminuyendo la percepción del mismo por parte del paciente, con una mejor tolerancia a la fisioterapia y reduciendo, en promedio, 15 horas de hospitalización y, por ende, los costos finales aproximados de la cirugía.

Reembolización de arterias uterinas por hemorragia posparto en una segunda gestación / Uterine artery embolization for postpartum hemorrhage in a second pregnancy

La hemorragia posparto es la principal causa de muerte obstétrica. Presentamos el caso de una gestación y parto normales tras la embolización bilateral de ambas arterias uterinas, por hemorragia posparto en la gestación anterior. La paciente requirió de una nueva embolización bilateral de arterias uterinas en esta segunda gestación con buen resultado obstétrico. La embolización arterial pélvica en el manejo de la hemorragia posparto refractaria al tratamiento médico, permite en ocasiones evitar el tratamiento quirúrgico, conservando la fertilidad de la paciente.

The postpartum hemorrhage is the main cause of obstetric death. We report a case of normal pregnancy and delivery after bilateral embolization of uterine arteries due to postpartum hemorrhage in a previous pregnancy. A new bilateral embolization of uterine arteries was needed in this second pregnancy with good obstetric results. The pelvic arterial embolization in the management of postpartum hemorrhage refractory to medical treatment, avoids the surgical treatment, preserving fertility.

Ictus isquémico poscefalea migrañosa en gestante a término / Ischemic ictus post migraine headache in a pregnancy woman

Se presenta el caso de una primigesta de 32 años que acude en la semana 38,3 por cefalea de carácter migrañoso de aparición brusca e intensidad moderada de dos días de evolución, asociada a fotopsias y a pérdida definida de un campo de la visión lateral izquierda. Tras descartar otra focalidad neurológica y preclampsia se comprueba el bienestar fetal y es valorada por oftalmólogos y neurólogos diagnosticando una cuadrantapnosia superior izquierda asociada a un síndrome de vasoconstricción cerebral reversible. La resonancia magnética revela un infarto cerebral en el territorio de la arteria cerebral posterior derecha y se comprueba en la angio-resonancia el defecto de repleción. Valorando la posibilidad de un inicio espontáneo del parto y la necesidad de iniciar tratamiento médico con ácido acetil salicílico para resolver el ictus se realiza una cesárea urgente con anestesia general con excelente resultado obstétrico y materno.

We report a case of a 38.3 weeks first prengancy woman o 32 year old who comes to the emergency service because she referred a two day acute migraine headache of sudden appereance with spintherism and a loose of a part of the left visual field. She did not had convulsive seizures nor strength or sensitive looses. Blood pressure was incongruous with preeclampsia, and she did not have proteinuria. After reassuring about well fetal being she is studied by ophtalmologists and neurologist who diagnose an of upper-left quadrantapnosia due to a reversible cerebral vasoconstriction syndrome. NMR and angio-NMR show a cerebral infarction in the right back cerebral artery area. Because of the risk of an spontaneous start of birth labour and the need of salicilyc acid treatment we decided to finish the pregnancy practising an urgent caesarean section under general anesthesic with an excellent mother and fetal result.

Embarazo con acromegalia materna asociada a crecimiento intrauterino fetal retardado / Pregnancy in acromegalic women associated with intrauterine growth restriction

La acromegalia es el exceso de secreción de hormona de crecimiento (HC). Esta alteración está relacionada con esterilidad y con complicaciones maternas durante el embarazo por aumento de la secreción de la HC. Presentamos el caso de una gestante diagnosticada de acromegalia persistente a pesar de haber sido operada vía transesfenoidal y tratada con cabergolina. Durante la gestación, la paciente no presentó complicaciones metabólicas ni tensionales, observándose un progresivo descenso de los niveles del factor de crecimiento insulínico-1 (IGF-I). El feto tuvo un crecimiento acorde con la amenorrea hasta la semana 31 en la que hizo una restricción del crecimiento con oligoamnios y alteración en el doppler en la semana 37. Se finalizó la gestación realizando una cesárea naciendo un recién nacido de 2400 gramos sin complicaciones neonatales. Aunque el curso del embarazo de las gestantes con acromegalia transcurre generalmente sin complicaciones, presentamos el primer caso descrito de un crecimiento intrauterino retardado en una paciente con acromegalia.

Pregnancy in acromegalic patients is an infrequent event, due to perturbed gonadotroph function. On the other hand, pregnancy may cause an enlargement of the adenoma or an increase of growth hormone (GH) secretion. We report the case of a pregnant acromegalic woman who had been previously operated by transphenoidal approach and treated with cabergolin. A progressive decrease of insuline-like growth factor-1 (IGF1) level during pregnancy without tumoral syndrome or visual troubles was shown during pregnancy. Neither metabolic complication nor hypertension were detected. Ultrasound performed at 31th week showed a decrease of the fetal growth. At 37th week, an intrauterine growth restriction and oligohydramnios was diagnosed. It was performed a cesarean section and it was delivered a healthy 2700 grams male newborn. Our report suggests that pregnancy could not influence negatively in acromegalic patient but may be associated with intrauterine growth restriction.

Validation of a capillary electrophoresis method for the analysis of ibandronate related impurities.

A capillary zone electrophoretic (CZE) method has been developed for the determination of impurities (phosphyte and phosphate) in technical-grade ibandronate, which is a potent nitrogen-containing bisphosphonate. Successful separation of the drug from the impurities was achieved using 1mM tetradecyl-trimethyl-ammonium bromide (TTAB) and 5mM potassium chromate (pH 10.0) as background electrolyte with an indirect detection at 254 nm. The optimised method was validated for specificity, precision, linearity and accuracy. The limit of detection (LOD) was 2 microg/mL and the limit of quantification (LOQ) was 7 microg/mL for both phosphyte and phosphate. The developed CZE method used to determine phosphyte and phosphate as bisphosphonates impurities can be used to evaluate the quality of regular production samples of ibandronate.

Comparación de susceptibilidad de especies de shigella a antimicrobianos de uso habitual en el Hospital Regional de Temuco, Chile 1990-2001 / Shigella species susceptibility to commonly used antimicrobials in the Temuco Regional Hospital, Chile 1990-2001

Background: The permanent surveillance of antimicrobial susceptibility of Shigella sp in the Temuco Regional Hospital, allowed us to define the empirical use of antimicrobials in dysenteric syndrome. Aim: To study antimicrobial susceptibility of Shigella strains collected from 1997 to May 2001 and compare the results with those reported in 1990. Material and methods: Two hundred and seventeen Shigella strains, coming from stool cultures of pediatric patients, were studied. Results: In the period 1989-1990 Shigella flexneri was the main species isolated (83 percent) whereas, in the period 1997-2001, Shigella sonnei (55.8 percent) predominated. In the second period, an increase of antimicrobial resistance, as compared with the period 1989-1990, was observed for ampicillin (74.5 and 42 percent respectively), for cotrimoxazol (57.5 and 45 percent respectively) and tetracycline (64 and 8 percent respectively). Chloramphenicol resistance increased from 0 to 57.5 percent. In the second period no resistance to ciprofloxacin was detected. There was simultaneous resistance to four drugs in 30 percent of the strains, predominating multiresistance in S flexneri (52.1 percent). Conclusions: In the two periods studied, a significant increase was detected in the resistance of Shigella strains to antimicrobials

Comparison of two different severity scores (Paediatric Risk of Mortality [PRISM] and the Glasgow Meningococcal Sepsis Prognostic Score [GMSPS]) in meningococcal disease: preliminary analysis.

Two different illness severity scores, Pediatric Risk of Mortality (PRISM) and the Glasgow Meningococcal Sepsis Prognostic Score (GMSPS), were evaluated and compared in meningococcal disease in two paediatric intensive care units. Forty-nine children with a median age of 36 months who had meningococcal sepsis confirmed by laboratory data were evaluated. Overall mortality was 18%. The median GMSPS was 3 in survivors and 8 in non-survivors. A GMSPS > or = 8 was significantly associated with death (p = 0.0001) with a mortality predictivity and specificity of 70% and 92.5%, respectively. The median PRISM score in survivors was 5.5 and 23 in non-survivors. A PRISM score of > or = 11 was significantly related to death (p < 0.0001). The Kendal correlation co-efficient between GMSPS and PRISM showed tau = 0.6859 (p = 0.0000). It is concluded that GMSPS and PRISM are useful methods for identifying and classifying children into low and high risk categories. GMSPS > or = 8 or a PRISM score > or = 11 are significantly predictive of mortality.

Resistencia de especies de shigella a antimicrobianos de uso habitual en el Hospital Regional Temuco, Chile / Resistance of the shigella species to regular antibiotics in the Regional Hospital of Temuco, Chile

El Hospital Regional de Temuco realiza vigilancia permanente de susceptibilidad a antimicrobianos en shigella detectándose desde 1996 resistencia progresiva a cloranfenicol, droga de elección en el tratamiento empírico frente a la sospecha de shigellosis. Se estudiaron 200 cepas de shigella aisladas de pacientes pediátricos que consultaron por diarrea entre julio 1997 y octubre 2000. La identificación bioquímica y serológica de las especies se realizó mediante metodología tradicional. La susceptibilidad a antimicrobianos de uso habitual, se midió mediante método de difusión en agar (Kirby-Bauer). Distribución por especies: shigella sonnei 64,5 por ciento y S. flexneri 35,5 por ciento. Se detectó 73 por ciento de resistencia a ampicilina, 56,5 por ciento a cloranfenicol, 45 por ciento a cotrimoxazol y 0 por ciento a ciprofloxacino. S. flexneri presentó resistencia y multirresistencia significativamente mayor. La resistencia limita las posibilidades terapéuticas, lo que incentiva a continuar con la vigilancia, para establecer normas de tratamiento y controlar la selección y diseminación de cepas multirresistentes

Evolution of the nutritional support pattern in pediatric intensive care.

OBJECTIVES: To evaluate patterns of usage and monitoring of nutritional support in a Pediatric ICU of a teaching hospital and the role of an education program in nutritional support given throughout the resident physician training. DESIGN: In a historical cohort study, records from children who received nutritional support during the year 1992 were analyzed. Thereafter a continuing education program in Nutritional Support was conveyed to the residents. In a second phase of the study, the same parameters were reevaluated in children who received nutritional support throughout the year 1995. SETTING: Pediatric Intensive Care Unit of Department of Pediatrics, Escola Paulista de Medicina. PATIENTS: All the children who were given nutritional support during a period of five days or more. Based on this criteria 37 children were selected for the first phase of this study, and 35 for the second one. INTERVENTION: The education program included theoretical lectures about basic themes of nutritional support and journal article reading sessions. It was given to successive groups of residents on a weekly schedule. MEASUREMENTS: Daily records of fluid, protein, caloric and micronutrient supply, nutritional assessment and metabolic monitoring. RESULTS: In the first phase of the study, an exclusively parenteral route was utilized for 80.5%, and a digestive route 19.5% of the time period. Nutritional assessment was performed on 3 children; no patient had the nutritional goals set. The nitrogen to nonprotein calories ratio and the vitamin supply were inadequate, whilst the supply of trace elements was adequate except for zinc. Nutritional monitoring was performed on almost all patients but without uniformity. In the second phase, the exclusive parenteral route was used for 69.7% and the digestive route for 30.3% of the time period; no significant increase in the use of the digestive route was detected. The nonprotein calories to nitrogen ratio and micronutrient supply were adequate. The frequency of nutritional assessment increased, but deficiency in nutritional monitoring and infrequent enteral feeding were still detected. CONCLUSION: There were deficiencies in the implementation of nutritional support, which were partially corrected in the second phase of the study by the training of the residents. Reinforcement of the education program, which should be applied to the whole medical staff, and the organization of a multidisciplinary team in charge of coordinating the provision of nutritional support are suggested.

Suporte nutricional-metabólico em UTI pediátrica / Nutricional and metabolic support in the pediatric ICU

O suporte nutricional tem sido considerado um recurso terapêutico importante no tratamento de crianças hospitalizadas e gravemente doentes. Com o conhecimento do padrao de suporte nutricional utilizado pela unidade de internaçao hospitalar, pode-se detectar falhas e propor medidas para a sua otimizaçao. OBJETIVO. Avaliar o padrao terapêutico e de monitorizaçao do suporte metabólico em uma Unidade de Terapia Intensiva Pediátrica e propor medidas mínimas para melhorar a sua qualidade. PACIENTES E MÉTODO. Foram analisados os prontuários de 37 crianças admitidas na unidade durante um ano e que receberam suporte nutricional por um período igual ou superior a 15 dias. RESULTADOS. Em um período de 425 dias de suporte nutricional, a via parenteral exclusiva foi utilizada em 8O,5 por cento do tempo e a via digestiva (sonda nasoenteral ou oral), em 19,5 por cento do tempo. A avaliaçao nutricional prévia foi realizada em apenas três pacientes (8,1 por cento). Apenas 29,7 por cento das crianças tiveram suas necessidades energéticas satisfeitas, e este objetivo foi alcançado apenas nas que estavam recebendo nutriçao enteral. A relaçao nitrogênio/calorias nao-protéicas variou de 1:8O a 1:250. A oferta de oligoelementos por via parenteral foi adequada, exceçao feita ao zinco. A administraçao das vitaminas A, B2, E, C, pantenol e niacina esteve aquém da recomendada; biotina, vitamina B12, e folado nao foram administrados. A monitorizaçao nutricional incluiu o peso corpóreo e as dosagens de albumina sérica e de triglicérides, e foi realizada na maior parte dos pacientes, embora de modo eventual e nao uniforme. Conclusao. Houve falhas na implementaçao do suporte nutricional, a saber: inadequaçao da oferta protéica e de micronutrientes, monitoraçao nutricional e metabólica deficiente e uso pouco freqüente de nutriçao por via enteral. Sugere-se uma rotina mínima para a monitorizaçao de pacientes em nutriçao parenteral e enteral e a organizaçao de uma equipe multidisciplinar encarregada da coordenaçao do suporte nutricional.

[Nutritional and metabolic support in the pediatric ICU]. / Suporte nutricional-metabólico em UTI pediátrica.

UNLABELLED: Nutritional support has been considered an important part of the treatment of critically ill patients. The information about the current clinical pattern of nutrition support in hospitals may provide a basis for future modification and improvement of its prescription and use. OBJECTIVES: 1) To evaluate patterns of usage and monitoring of nutritional support in critically ill children; 2) To recommend policies aiming at the improvement of the nutritional support quality. PATIENTS AND METHOD: Records of 37 patients receiving nutritional support throughout one year were reviewed. RESULTS: From a total of 425 days of therapy, the single parenteral route was utilized in 80.50% the digestive route (tube feeding or oral route) in 19.5% of this time. A previous nutritional assessment was performed in 3 children; no patient had the nutrition goals set. The nitrogen to nonprotein calories ratio ranged between 1:80 and 1:250. Only 29.7% of the patients had their estimated caloric needs supplied and this goal was achieved only in those patients who were on enteral tube feeding. Patients did not achieved their goals for vitamins. The supply of oligoelements was adequate except zinc. Nutritional monitoring parameters including weight, serum albumin and serum triglycerides were performed in almost all the patients but without uniformity. CONCLUSION: There was a lack in the implementation of nutritional support. Inadequacy of protein and micronutrients supply, irregular nutritional monitoring and infrequent enteral feeding were detected. A minimal standard for nutritional and metabolic monitoring and the organization of a multidisciplinary team in charge of coordinating the providing of nutritional support are suggested.

Precancerous pathology evoked by hexachlorobenzene treatment.

The porphyrinogenic and carcinogenic ability of hexachlorobenzene (HCB) was assayed in male and female gold hamsters, and histological examinations of tissue alterations were performed. So it was studied, in liver: a) porphyrin content which was significantly increased at five months of HCB treatment, specially in males, and the pattern of accumulated porphyrins which was altered independent of the sex, b) haem pathway enzymes:delta aminolaevulinic acid synthase, ferrochelatase and porphyrinogen carboxylyase (PCL); among which only PCL appeared to be altered just at ten months of HCB feeding. While thyroid gland and kidney remained unaltered along the treatment time, liver and spleen exhibited a noticeable size variation and morphological alterations. In fact the spleen in treated animals was hypotrophic showing a red pulp less developed with respect to the Malpighian corpuscles and many macrophages with iron deposits. Respect to the liver, enlargement in size of hepatocytes, high content of iron deposits, no PAS positive structures in the cytoplasm, several small lipid droplets, microsteatosis although no cytonecrosis, polymorphic nuclei, and proliferations of nucleoli were observed. Therefore HCB is able to cause precancerous pathology and to induce porphyria in hamsters, but not hyperthyroidism, upon this experimental conditions. By the way, males were found to be a good experimental model, better than females, to study the earliest relations between porphyria and cancer.

Porphyrinogen carboxylyase. Studies on the existence of isoenzymes.

Porphyrinogen carboxylyase from normal rat liver was subjected to purification methods. Two different purification protocols were used. In both cases, the initial steps consisted in obtaining a liver homogenate, followed by centrifugation, salt precipitation and phosphate gel absorption. Scheme I consisted in then submitted the preparation to DEAE-cellulose, followed by Sephacryl S-200 and Phenyl-sepharose sequential column chromatographies. Scheme II involved an affinity column followed by a Sephadex G-75 gel filtration column. In both cases, the enzyme was stored at -20 degrees C until its assay. The addition of 2mM dithiotreytol to the incubation media or to the enzyme extract before storage, did not help improve the activity nor the stability of the enzyme. Those fractions containing the maximal enzyme activity, detected using Uroporphyrinogen III or Pentacarboxy-porphyrinogen III as substrate, were not always present in the same tubes for the different columns employed. In addition, the degree of purification obtained in some steps was different according to the substrate employed. The results suggest the existence of at least two isoenzymes for rat liver porphyrinogen carboxy-lyase.

Precancerous pathology evoked by hexachlorobenzene treatment

The porphyrinogenic and carcinogenic ability of hexachlorobenzene (HCB) was assayed in male and female gold hamsters, and histological examinations of tissue alteraions were performed. So it was studied, in liver: a) prophyrin content which was significantly increased at five months of HCB treatment, specially in males, and the pattern of accumalated porphyrins which was altered independent of the sex, b) haem pathway enzymes: delta aminolaevulinicacid synthase, ferrochelatase and porphyrinogen carboxylyase (PCL); among which only PCL appeared to be altered just at ten months of HCB feeding. While thyroid gland and kidney remained unaltered along the treatment time, liver and spleen exhibited a noticeable size variation and morphological alterations. In fact the spleen in treated animals was hypotrophic showing a red pulp less developed with respect to the Malpighian corpuscles and many macrophages with iron deposits. Respect to the liver, enlargement in size of hepatocytes, high content of iron deposits, no PAS positive structures in the cytoplasm, several small lipid droplets, microsteatosis although no cytonecrosis, polymorphic nuclei, and proliferations of nucleoli were observed. Therefore HCB is able to cause precancerous pathology and to induce porphyria in hamster, but not hyperthyroidism, upon this experimental conditions. By the way, males were found to be a good experimental model, better than females, to study the earliest relations between porphyria and cancer.

Precancerous pathology evoked by hexachlorobenzene treatment

The porphyrinogenic and carcinogenic ability of hexachlorobenzene (HCB) was assayed in male and female gold hamsters, and histological examinations of tissue alteraions were performed. So it was studied, in liver: a) prophyrin content which was significantly increased at five months of HCB treatment, specially in males, and the pattern of accumalated porphyrins which was altered independent of the sex, b) haem pathway enzymes: delta aminolaevulinicacid synthase, ferrochelatase and porphyrinogen carboxylyase (PCL); among which only PCL appeared to be altered just at ten months of HCB feeding. While thyroid gland and kidney remained unaltered along the treatment time, liver and spleen exhibited a noticeable size variation and morphological alterations. In fact the spleen in treated animals was hypotrophic showing a red pulp less developed with respect to the Malpighian corpuscles and many macrophages with iron deposits. Respect to the liver, enlargement in size of hepatocytes, high content of iron deposits, no PAS positive structures in the cytoplasm, several small lipid droplets, microsteatosis although no cytonecrosis, polymorphic nuclei, and proliferations of nucleoli were observed. Therefore HCB is able to cause precancerous pathology and to induce porphyria in hamster, but not hyperthyroidism, upon this experimental conditions. By the way, males were found to be a good experimental model, better than females, to study the earliest relations between porphyria and cancer. (AU)

Immunoassay with recombinant Trypanosoma cruzi antigens potentially useful for screening donated blood and diagnosing Chagas disease.

A new enzyme immunoassay (EIA), the Dia Kit Bio-Chagas assay (Gador S.A.), is potentially useful for detecting antibodies to Trypanosoma cruzi in the diagnosis of infected individuals and the screening of blood in blood banks. The EIA is carried out on test strips of plastic backing covered with a nitrocellulose membrane to which a mixture of recombinant T. cruzi antigens 1, 2, shed acute-phase antigen, 13, and 30 has been applied as a horizontal line. A horizontal line of human IgG is included to monitor the test procedure. The test strips exhibited homogeneity in the adsorption of the mixture of recombinant antigens (CV = 6.0%) and the human IgG (CV = 8.6%). The EIA results obtained with sera positive by xenodiagnosis showed 100% agreement between both types of tests; tested against sera with positive and negative matched results of indirect hemagglutination, immunofluorescence, and ELISA, the EIA results agreed for 99.1% (347 of 350) and 99.6% (299 of 300) of the samples, respectively.