[Diaphyseal osteoporotic nonunion of the humerus in elderly patients. Surgical treatment and long-term results]. / No-consolidación diafisaria de húmero en pacientes adultos con osteoporosis. Tratamiento quirúrgico y resultados a largo plazo.

INTRODUCTION: to evaluate the long term radiographic and functional results achieved in adult patients with osteoporotic, atrophic, non-unions of the diaphyseal humerus, treated surgically by open reduction and internal fixation with plates and bone graft. MATERIAL AND METHODS: we retrospectively evaluated 22 patients. Patient's age averaged 72 years. Time from initial trauma to definitive surgery averaged 18 months. Eleven patients were smokers, and four had active infection. Pre-operative Constant score and DASH score averaged 23.13 and 81.04, respectively. Pre-operative pain scale averaged 7.45 points. RESULTS: follow-up averaged 69 months. Union was achieved in all cases after an average of 4.68 months. DASH score at last follow-up averaged 20.27 points and Constant score 79.31 points. Analog pain scale averaged 0.77 points. Stabilization was performed using locking blade plates in 12 non-unions, locking compression plates in six cases, and double plating in four non-unions. Patients with active infection were treated in two stages using Masquelet's technique. Bone graft was associated in all cases (cancellous iliac crest autograft in 17, allograft in three, and combined structural allograft and cancellous autograft in two). Two grams of vancomycin powder were associated to the bone graft in all cases. CONCLUSION: the use of open reduction and internal fixation with plates associated to bone graft with local antibiotics, aloud achieving bony union and good predictable long-term objective and subjective functional results in all cases, without major complications or the need of further surgical intervention.

INTRODUCCIÓN: evaluar los resultados radiográficos y funcionales obtenidos a largo plazo en pacientes adultos que presentaron no-consolidaciones atróficas diafisarias de húmero asociadas a osteoporosis; tratadas quirúrgicamente mediante reducción abierta y fijación interna con placas e injerto óseo. MATERIAL Y MÉTODOS: evaluamos retrospectivamente 22 pacientes, con edad promedio de 72 años, el tiempo desde el trauma inicial hasta la cirugía definitiva promedió, 18 meses. Once pacientes eran fumadores y cuatro presentaban infección activa. El score de Constant y el DASH preoperatorios promediaron 23.13 y 81.04, respectivamente. El valor de la escala analógica del dolor preoperatorio promedió 7.45 puntos. RESULTADOS: el seguimiento promedió 69 meses. Se obtuvo la consolidación en todos los casos, luego de un promedio de 4.68 meses. Al último seguimiento, los valores del DASH promediaron 20.27 puntos y el score de Constant promedió 79.31 puntos. La escala analógica del dolor promedió 0.77 puntos. La estabilización se realizó utilizando clavos placa bloqueados en 12 no-consolidaciones, placas bloqueadas de compresión en seis y doble placa en cuatro. Los pacientes con infección activa fueron tratados en dos etapas utilizando la técnica descripta por Masquelet. Se asoció injerto óseo en todas las reconstrucciones (autoinjerto esponjoso de cresta ilíaca en 17, aloinjerto en tres y se combinó aloinjerto estructural con autoinjerto esponjoso en dos). Dos gramos de vancomicina en polvo fueron asociados localmente al injerto óseo. CONCLUSIÓN: la combinación de reducción abierta y fijación interna con placas e injerto óseo permitió obtener la consolidación y resultados funcionales objetivos y subjetivos buenos y predecibles a largo plazo en todos los casos, sin complicaciones mayores ni la necesidad de intervenciones quirúrgicas sucesivas.

Sunlight Effects on Immune System: Is There Something Else in addition to UV-Induced Immunosuppression?

Sunlight, composed of different types of radiation, including ultraviolet wavelengths, is an essential source of light and warmth for life on earth but has strong negative effects on human health, such as promoting the malignant transformation of skin cells and suppressing the ability of the human immune system to efficiently detect and attack malignant cells. UV-induced immunosuppression has been extensively studied since it was first described by Dr. Kripke and Dr. Fisher in the late 1970s. However, skin exposure to sunlight has not only this and other unfavorable effects, for example, mutagenesis and carcinogenesis, but also a positive one: the induction of Vitamin D synthesis, which performs several roles within the immune system in addition to favoring bone homeostasis. The impact of low levels of UV exposure on the immune system has not been fully reported yet, but it bears interesting differences with the suppressive effect of high levels of UV radiation, as shown by some recent studies. The aim of this article is to put some ideas in perspective and pose some questions within the field of photoimmunology based on established and new information, which may lead to new experimental approaches and, eventually, to a better understanding of the effects of sunlight on the human immune system.

Time course of systemic oxidative stress and inflammatory response induced by an acute exposure to Residual Oil Fly Ash.

It is suggested that systemic oxidative stress and inflammation play a central role in the onset and progression of cardiovascular diseases associated with the exposure to particulate matter (PM). The aim of this work was to evaluate the time changes of systemic markers of oxidative stress and inflammation, after an acute exposure to Residual Oil Fly Ash (ROFA). Female Swiss mice were intranasally instilled with a ROFA suspension (1.0mg/kg body weight) or saline solution, and plasma levels of oxidative damage markers [thiobarbituric acid reactive substances (TBARSs) and protein carbonyls], antioxidant status [reduced (GSH) and oxidized (GSSG) glutathione, ascorbic acid levels, and superoxide dismutase (SOD) activity], cytokines levels, and intravascular leukocyte activation were evaluated after 1, 3 or 5h of exposure. Oxidative damage to lipids and decreased GSH/GSSG ratio were observed in ROFA-exposed mice as early as 1h. Afterwards, increased protein oxidation, decreased ascorbic acid content and SOD activity were found in this group at 3h. The onset of an adaptive response was observed at 5h after the ROFA exposure, as indicated by decreased TBARS plasma content and increased SOD activity. The observed increase in oxidative damage to plasma macromolecules, together with systemic antioxidants depletion, may be a consequence of a systemic inflammatory response triggered by the ROFA exposure, since increased TNF-α and IL-6 plasma levels and polymorphonuclear leukocytes activation was found at every evaluated time point. These findings contribute to the understanding of the increase in cardiovascular morbidity and mortality, in association with environmental PM inhalation.

Activity modulation of microbial enzymes by llama (Lama glama) heavy-chain polyclonal antibodies during in vivo immune responses.

Since they were first described in 1993, it was found that recombinant variable fragments (rVHHs) of heavy-chain antibodies (HCAbs) from Camelidae have unusual biophysical properties, as well as a special ability to interact with epitopes that are cryptic for conventional Abs. It has been assumed that in vivo raised polyclonal HCAbs (pHCAbs) should behave in a similar manner than rVHHs; however, this assumption has not been tested sufficiently. Furthermore, our own preliminary work on a single serum sample from a llama immunized with a ß-lactamase, has suggested that pHCAbs have no special ability to down-modulate catalytic activity. In this work, we further explored the interaction of pHCAbs from four llamas raised against two microbial enzymes and analyzed it within a short and a long immunization plan. The relative contribution of pHCAbs to serum titer was found to be low compared with that of the most abundant conventional subisotype (IgG(1)), during the whole immunization schedule. Furthermore, pHCAbs not only failed to inhibit the enzymes, but also activated one of them. Altogether, these results suggest that raising high titer inhibitory HCAbs is not a straightforward strategy - neither as a biotechnological strategy nor in the biological context of an immune response against infection - as raising inhibitory rVHHs.

Cambios en la perfusión cerebral inducidos por etomidato en pacientes con epilepsia del lóbulo temporal / Changes in cerebral perfusión induced by etomidate in patients with temporal lobe epilepsy

Resumen. Introducción. La epilepsia es uno de los mayores trastornos neurológicos. Afecta a alrededor del 0,5-2% de la población mundial, y entre el 20-25% de los pacientes son resistentes a la medicación. Objetivo. Analizar la respuesta de la perfusión cerebral –valorada mediante tomografía simple por emisión de fotón único (SPECT)– y la actividad bioeléctrica –en scalp y región temporal mesial– a la aplicación de etomidato. Pacientes y métodos. Se estudiaron 10 pacientes evaluados prequirúrgicamente y estudiados mediante videoelectroencefalograma (video-EEG) con electrodos de foramen oval (EFO) y SPECT. Se administró etomidato (0,1 mg/kg de peso), seguido por 99mTc-HmPAO, durante el estudio en el video-EEG + EFO. Resultados. Los efectos secundarios consistieron en mioclonías (n = 7) y dolor moderado (n = 2). No se han observado efectos cardiovasculares o respiratorios significativos. La actividad bioeléctrica en scalp consistió en una actividad rápida inicial breve, seguida por un patrón delta generalizado e hipervoltado durante varios minutos. En la región irritativa, se observó un marcado incremento de la actividad interictal. La perfusión cerebral aumentó, en general en todas las áreas estudiadas, especialmente en la región temporal (lateral y mesial) y en las áreas talámicas. En la cola del hipocampo no epileptógeno, se ha observado el segundo mayor incremento en la perfusión cerebral, y es la única región que se diferencia de la contralateral. Conclusiones. La activación mediante etomidato da lugar a una respuesta específica y repetible sobre la actividad bioeléctrica. Además, la perfusión cerebral local muestra cambios relacionados directamente con la región epileptógena, y puede servir, por tanto, como herramienta diagnóstica en un futuro inmediato (AU)

Summary. Introduction. Epilepsy is one of the major neurological disorders, affecting roughly 0.5-2% of the world’s population and approximately 20-25% of patients are resistant to medication. Aim. To analyze the response of cerebral perfusion (assessed by SPECT) and bioelectrical activity (measured in scalp and mesial temporal region) to etomidate. Patients and methods. We studied 10 patients presurgically evaluated and studied by video-EEG with foramen ovale electrodes (EFO) and SPECT. Etomidate was administered (0.1 mg/kg), followed by 99mTc-HmPAO during the study in the video-EEG + EFO. Results. The side-effects consisted of myoclonus (n = 7) and moderate pain (n = 2). There had been no significant respiratory or cardiovascular effects. The bioelectrical activity in the scalp consisted in a brief initial rapid activity, followed by a generalized and hypervoltaged delta pattern for several minutes. In the epileptogenic zone, there was a marked increase of interictal activity. Increased cerebral perfusion was observed in all areas studied, especially in temporal region (mesial and lateral) areas and thalamus. In the tail of the non-epileptic hippocampus, we observed the second largest increase in cerebral perfusion, the only region that is different from contralateral area. Conclusions. Activation by etomidate induces a specific and repetitive response in the bioelectrical activity. In addition, cerebral perfusion changes directly related to the epileptogenic region may serve therefore as a diagnostic tool in the near future (AU)

[Changes in cerebral perfusion induced by etomidate in patients with temporal lobe epilepsy]. / Cambios en la perfusión cerebral inducidos por etomidato en pacientes con epilepsia del lóbulo temporal.

INTRODUCTION: Epilepsy is one of the major neurological disorders, affecting roughly 0.5-2% of the world's population and approximately 20-25% of patients are resistant to medication. AIM: To analyze the response of cerebral perfusion (assessed by SPECT) and bioelectrical activity (measured in scalp and mesial temporal region) to etomidate. PATIENTS AND METHODS: We studied 10 patients presurgically evaluated and studied by video-EEG with foramen ovale electrodes (EFO) and SPECT. Etomidate was administered (0.1 mg/kg), followed by (99)mTc-HmPAO during the study in the video-EEG + EFO. RESULTS: The side-effects consisted of myoclonus (n = 7) and moderate pain (n = 2). There had been no significant respiratory or cardiovascular effects. The bioelectrical activity in the scalp consisted in a brief initial rapid activity, followed by a generalized and hypervoltaged delta pattern for several minutes. In the epileptogenic zone, there was a marked increase of interictal activity. Increased cerebral perfusion was observed in all areas studied, especially in temporal region (mesial and lateral) areas and thalamus. In the tail of the non-epileptic hippocampus, we observed the second largest increase in cerebral perfusion, the only region that is different from contralateral area. CONCLUSIONS: Activation by etomidate induces a specific and repetitive response in the bioelectrical activity. In addition, cerebral perfusion changes directly related to the epileptogenic region may serve therefore as a diagnostic tool in the near future.

[Nursing in the advanced chronic kidney disease (ACKD) unit]. / Enfermeria en la consulta de enfermedad renal cronica avanzada (ERCA).

ACKD units should be equipped with a nephrology nurse, who to carry out his/her function adequately and contribute to the objectives of the ACKD unit should have the following: - Specific training as a nephrology nurse. - Own work area and appointments schedule. - Full-time commitment to nephrology. - A direct phone line to be able to contact patients and vice versa. - Well-established communication channels between nursing staff and nephrologists. Objectives of the nephrology nursing unit: - Patients treated in this unit have a CrCl < or >or= 30 ml/min. - Foster self-care and patient autonomy. - Preserve GFR as long as possible by delaying progression of the disease. - Optimize patient quality of life in the pre-KRT period. - Reduce comorbidity. - Support patient in the decision on KRT. - Coordinate planning of vascular access and/or peritoneal catheter. - Schedule entry into chosen kidney replacement therapy, preventing complications and use of temporary accesses. - The nurse of this unit should be trained in clinical interviewing techniques.

[Access for starting kidney replacement therapy: vascular and peritoneal temporal access in pre-dialysis]. / Accesos para comenzar depuracion extrarrenal: vascular y peritoneal. acceso temporal en pre-dialisis.

UNLABELLED: PATIENT EVALUATION AND PREPARATION PRIOR TO VASCULAR ACCESS (VA) PLACEMENT: 1. Early referral of patients with advanced chronic kidney disease (ACKD: GFR

[Patients in pre-dialysis: decision taking and free choice of treatment]. / El paciente en pre-dialisis: toma de decisiones y libre eleccion terapeutica.

Predialysis is a clinical situation in which the patient has significant impairment of kidney function that will ultimately lead to either death or inclusion in kidney replacement therapy (dialysis and/or transplantation). Since a practical and effective dialysis technique was introduced, the length and quality of survival of patients with end-stage renal failure has constantly increased. Contraindications for dialysis are almost never of a renal origin. The obstacles are the concomitant diseases of the patient. The age of the patient may be one of these obstacles. The average age at initiation of dialysis in our country is currently 67 years and over 50% of patients are 60 years old or older. Decision making: From an ethical viewpoint, there is a consensus in stating that anything that can technically be done, should be done. The principle of nonmaleficence and respect for the autonomy of the patients are "prima facie" principles when the physician has doubts as to whether dialysis provides a benefit to the patient. The principle of autonomy, which makes the patient a competent subject of treatment, allows a framework of shared decisions to be created in which the physician uses his knowledge and experiences in assessing the risk and benefits of dialysis including the alternative of no dialysis. The competent patient, duly informed, will chose the option that is best for him and take the decision. Principle of treatment proportionality: This principle states that there is a moral obligation to implement all therapeutic measures that show a relationship of due proportion between the resources used and the expected result. Dialysis is in principle a proportional treatment for end-stage renal failure. However, it may become a disproportional treatment because of the physical and mental conditions of the elderly patient. The good that is sought with institution of treatment can cause a harm to the patient that justifies noninclusion of the patient in dialysis treatment. Because of the impossibility of establishing universal rules of proportionality, it is necessary to make a personal judgment of conscience in each specific case. Recommendations for initiation or not of dialysis: Taking shared decisions between the patient (or relatives and/or advisors) and the physician. These shared decisions will be documented with signing of the proposed informed consent or rejection of the treatment. The medical team should always be sure that the patients has fully understood the consequences of the decision taken. Explanation of the modalities should include: - Types of dialysis treatment available. - Not to initiate dialysis and continue with conservative treatment until death. This situation may cause many problems if we do not have the help of the palliative care service. - Try dialysis for a limited time. - Stop dialysis and receive medical care until death. - Evaluate the prognosis of renal disease and concomitant diseases, life expectancy and family support. Resolution of conflicts: Conflicts may occur: - Between nephrologist and patient/family. - Between members of the nephrological team. - Between nephrologist and other physicians. When conflicts persist and the need for initiation of dialysis is urgent, it is necessary to initiate treatment and continue it until the resolution of these conflicts, making a record of this decision. In such cases, the Hospital Ethics Care Committee can help with appropriate advice to solve the discrepancies. Decisions taken in advance may be useful in this type of patients. Patients with advanced chronic kidney disease with criteria for Noninclusion or withdrawal of dialysis. - Severe or irreversible dementia. - conditions of permanent unconsciousness. - advanced tumors with metastasis. - terminal disease of another nontransplantable organ. - severe physical and/or mental disabilities. (Strength of Recommendation C)

[Impact of experience on improving the surgical outcome in temporal lobe epilepsy]. / Impacto de la experiencia sobre los resultados quirúrgicos en la epilepsia del lóbulo temporal.

INTRODUCTION: Recently, we have published the results of a first surgical series of patients with temporal lobe epilepsy (TLE). We describe a posterior series of patients intervened of TLE, we compare the functional results with the previous series and we finally analyze the causes of changes. PATIENTS AND METHODS: We studied the first 22 consecutive patients surgically intervened of TLE with a minimum post-surgery follow-up of 2 years. Patients showing I and II Engel's grade were used as gold standard for evaluation of pre-surgical complementary studies. RESULTS: We have obtained better functional results: 91% patients showing Engel's grade I, 9% showing grade II and neither III nor IV grades were obtained. Pre-surgical studies changed in comparison with the previous report. The most improving change was observed in video-EEG with foramen-ovale electrodes (FOE) (37%), scalp EEG (26.6%), interictal SPECT (11.7%) and MRI (11.7%). Video-EEG with FOE was the study than showed greater concordance with epileptic focus (95.5%), followed by EEG (86.4%). In 35% of cases, MRI was normal or without valid data for correct localization of focus. CONCLUSIONS: Video-EEG with FOE and TLE surgery are safety methods, which results improve with the experience. Normal or not informative MRI do not should a priori reject those patients with drug-resistant TLE from surgery.

Impacto de la experiencia sobre los resultados quirúrgicos en la epilepsia del lóbulo temporal / Impact of experience on improving the surgical outcome in temporal lobe epilepsy

Introducción. Hemos publicado recientemente los resultados de una primera serie quirúrgica de pacientes con epilepsia del lóbulo temporal (ELT). Se presenta una serie inmediatamente posterior, y se analizan y comparan los resultados. Pacientes y métodos. Se estudian 22 pacientes nuevos intervenidos consecutivamente de ELT, con igual metodología que en la publicación previa y con un control clínico mínimo de dos años. Para evaluar la capacidad para localizar el foco de las pruebas complementarias se utilizó como estándar de oro los pacientes con grados I o II de Engel. Resultados. Se han obtenido mejores resultados funcionales: 91% de pacientes en grado I y 9% en grado II de Engel. No se han obtenido pacientes en grados III o IV. Los estudios prequirúrgicos que, comparativamente, han incrementado más su capacidad de localización fueron: videoelectroencefalograma (vídeo-EEG) con electrodos del foramen oval (EFO) (37,0%), EEG de scalp (26,6%), tomografía computarizada por emisión de fotón único (SPECT) interictal (11,7%) y la resonancia magnética (RM) (7,3%). La prueba con mayor grado de concordancia con el foco epileptógeno fue el vídeo-EEG con EFO (95,5%), seguido del EEG (86,4%). En un 35% de los estudios, la RM fue normal o sin datos válidos para la localización del foco epileptógeno. Conclusiones. La exploración con EFO y el tratamiento quirúrgico de la ELT es una metodología segura, cuyos resultados mejoran con la experiencia. La RM normal o no claramente informativa no tiene por qué excluir a priori a los pacientes con ELT farmacorresistente de esta alternativa terapéutica

Introduction. Recently, we have published the results of a first surgical series of patients with temporal lobe epilepsy (TLE). We describe a posterior series of patients intervened of TLE, we compare the functional results with the previous series and we finally analyze the causes of changes. Patients and methods.We studied the first 22 consecutive patients surgically intervened of TLE with a minimum post-surgery follow-up of 2 years. Patients showing I and II Engel’s grade were used as gold standard for evaluation of pre-surgical complementary studies. Results. We have obtained better functional results: 91% patients showing Engel’s grade I, 9% showing grade II and neither III nor IV grades were obtained. Pre-surgical studies changed in comparison with the previous report. The most improving change was observed in video-EEG with foramen-ovale electrodes (FOE) (37%), scalp EEG (26.6%), interictal SPECT (11.7%) and MRI (11.7%). Video-EEG with FOE was the study than showed greater concordance with epileptic focus (95.5%), followed by EEG (86.4%). In 35% of cases, MRI was normal or without valid data for correct localization of focus. Conclusions. Video-EEG with FOE and TLE surgery are safety methods, which results improve with the experience. Normal or not informative MRI do not should a priori reject those patients with drug-resistant TLE from surgery

[Reconstruction of thoracolumbar spine instability: clinical and neuroradiological results of a surgical challenge]. / Reconstrucción de la columna toracolumbar inestable: resultados clínicos y neurorradiológicos de un desafío quirúrgico.

INTRODUCTION: Surgical treatment for thoracolumbar union instability represents a challenge, due to the difficult access to this area of the spine, and to the extreme variability of morphological and biomechanical lesions observed. AIM: To describe the indications and clinical and neuroradiological results obtained with procedures of anterior or combined spinal fusion-instrumentation used for the treatment of instable thoracolumbar lesions. PATIENTS AND METHODS: 17 patients with thoracolumbar instability were treated surgically, being followed-up at least for one year. Causes of instability were classified in three groups: (i) fractures or fracture-luxations (n = 7), (ii) pathologic fractures following tumoral invasion (n = 6) and (iii) infectious or degenerative spondylodiscitis (n = 5). In order to carry out the substitution of the injured vertebral body an anterior approach to the thoracolumbar union was performed in all cases, using a modified technique of thoracophrenolaparotomy in which the diaphragmatic dome was not incised. Depending on the number of columns of Denis damaged, the vertebral corpectomy was followed by either an anterolateral or a combined spinal fusion-instrumentation. RESULTS: Pain in standing position was eliminated postoperatively in 83%. Neurological deficits were improved in 50% of cases. Surgical mortality was null and transient postoperative complications occurred in 11.7% of patients, but no lung atelectasis or respiratory infections were observed. CONCLUSIONS: Chronic pain associated to thoracolumbar instability can be treated successfully by substitution of the damaged vertebral body followed by anterior or combined spinal fusion-instrumentation. Thoracophrenolaparotomy without division of the diaphragm is feasible and it reduces the morbidity associated to postoperative respiratory complications.

Cambio del isotipo en la respuesta a antígenos T independientes por co-inoculación con antígenos T dependientes / Isotype switch in the response against T independent antigens by co-inoculation with T dependent antigens

Un paradigma clásico de la inmulogía plantea que para que ocurra cambio de isotipo en los anticuerpos es condición sine qua non la presentación del antígeno a un linfócito T colaborador por parte de una célula presentadora de antígenos. En el presente trabajo se diseñó un modelo animal, ratones BALB/c, de respuesta inmune frente a dos antígenos típicos. Se utilizo dextrán como antígeno T independiente (AgTI) y seroalbúmina bovina (SAB) como antígeno T dependiente (AgTD), y se estúdio la respuesta, analizando los isotipos de los anticuerpos específicos producidos. Los resultados obtenidos muestran que la respuesta a dextrán en presencia de SAB ocurre con cambio de isotipo (swith), essencialmente de IgM a IgG. Estos experimentos sugieren que la SAB genera un entorno bioquímico inductor de cambio de isotipo tanto en supropia via de procesamiento como en del dextrán. Los resultados señalan que la asociación exclusiva de los AgTDs con las respuestas em las que ocurre cambio de isotipo es incorrecta. Considerando el modelo propuesto resulta poco probable encontrar in vivo y en forma espontânea casos en los que los AgTIs ingreses al organismo aislados; en cambio, es mucho más probable que el ingreso ocurra conjuntamente con AgTDs, y en consecuencia ocurra cambio de isotipo.

Cambio del isotipo en la respuesta a antígenos T independientes por co-inoculación con antígenos T dependientes / Isotype switch in the response against T independent antigens by co-inoculation with T dependent antigens

Un paradigma clásico de la inmulogía plantea que para que ocurra cambio de isotipo en los anticuerpos es condición sine qua non la presentación del antígeno a un linfócito T colaborador por parte de una célula presentadora de antígenos. En el presente trabajo se diseñó un modelo animal, ratones BALB/c, de respuesta inmune frente a dos antígenos típicos. Se utilizo dextrán como antígeno T independiente (AgTI) y seroalbúmina bovina (SAB) como antígeno T dependiente (AgTD), y se estúdio la respuesta, analizando los isotipos de los anticuerpos específicos producidos. Los resultados obtenidos muestran que la respuesta a dextrán en presencia de SAB ocurre con cambio de isotipo (swith), essencialmente de IgM a IgG. Estos experimentos sugieren que la SAB genera un entorno bioquímico inductor de cambio de isotipo tanto en supropia via de procesamiento como en del dextrán. Los resultados señalan que la asociación exclusiva de los AgTDs con las respuestas em las que ocurre cambio de isotipo es incorrecta. Considerando el modelo propuesto resulta poco probable encontrar in vivo y en forma espontÔnea casos en los que los AgTIs ingreses al organismo aislados; en cambio, es mucho más probable que el ingreso ocurra conjuntamente con AgTDs, y en consecuencia ocurra cambio de isotipo. (AU)

Antimicrobial effect of chlorine on Yersinia enterocolitica.

The effects of chlorine at varying pH, culture media and incubation temperatures on one type and two wild type strains of Yersinia enterocolitica were studied. Exposure to 1 and 5 mg 1(-1) did not diminish viability, even after prolonged exposure. A level of 10 mg 1(-1) was required to achieve a 5-log reduction in 120 s for the type strain and 80 s for the wild strains. There was an increase of more than 30% in the rate of disinfection with a 10 degrees C rise, a remarkable increase in antimicrobial activity at pH 5-log reduction in 20 s, as well as marked neutralization of the effect in the presence of 0.1% peptone. Younger cells were more susceptible than older ones, and those from liquid medium more resistant than those from solid medium. Incubation temperature of a 24-h inoculum failed to show any influence. Lastly, there was a noteworthy demand for free chlorine by bacterial biomass, with agreement of the curve depicting the drop in free chlorine in the presence of inoculum with biphasic kinetics of survival curves.

[Plasmodium falciparum resistant to sulfadoxine/pyrimethamine in Senegal]. / Plasmodium falciparum resistente a sulfadoxina/pirimetamina en el Senegal.

In 1983, the first African cases of malaria due to Plasmodium falciparum resistant to sulfadoxine/pyrimethamine, were described. Currently, this resistance is frequently found in Kenya and Tanzania. It has also been described in other African countries. A young Spanish woman contracted Plasmodium falciparum malaria in Senegal and was treated in our hospital with sulfadoxine/pyrimethamine. Fever and symptoms disappear within two days. The thick smears taken on the eighth and thirteenth days of treatment contained an abundance of gametocytes, but neither trophozoites nor schizonts. As the risk of transmission of malaria to the rest of the community was considered practically nil, no other treatment was administered. A month late, she was admitted to the hospital due to fever, shivering, fatigue, loss of appetite and hemolytic anaemia. The thick smear test again showed trophozoites of P. Falciparum. Thus, it proved to be a delayed grade I resistance to sulfadoxine/pyrimethamine, detected in far west Africa. An oral dose of mefloquine was administered as well as a red cell transfusion. Both fever and symptoms finally disappeared.

[Hansenula anomala infection in acute leukemia]. / Infección por Hansenula anomala en leucemia aguda.

Hansenula anomala infection is a clinical rarity which has only been reported in 21 cases. Although most reported cases had one or more of the risk factors of fungemia, only three developed in hematological patients. In the present study we report two cases of Hansenula anomala infection in acute leukemia, one in its teleomorphic form and another in the asexual form of this yeast, Candida pelliculosa. The sustained chemotherapy and steroid and antibiotic treatment were some of the risk factors of fungemia which were present in these patients, one of which was a carrier of a central venous catheter. As it has been suggested that Hansenula anomala has a low virulence and a high susceptibility to amphotericin B, we emphasize the potential morbidity and mortality that this organism can induce in patients with hematological disease.

A comparative study of the RAST, indirect haemagglutination, basophil degranulation and latex tests in the diagnosis of human hydatid disease.

In order to compare the diagnostic efficacy of the, basophil degranulation, RAST, indirect haemagglutination and latex tests, we carried out these four tests on 50 patients with confirmed hydatid disease due to Echinococcus granulosus. As a control group we employed 50 subjects who showed no evidence of hydatid disease or any other parasitic disease. The test which displayed the highest degree of diagnostic efficacy was the basophil degranulation test with a sensitivity of 93% and an accuracy of 97%. Next in diagnostic efficacy were the haemagglutination and RAST tests with very similar results-a sensitivity of 82% and an accuracy of 91% for the former, and for the latter a sensitivity of 80% and an accuracy of 90%. The latex test, with a sensitivity of 67% and an accuracy of 83%, possessed the lowest degree of diagnostic efficacy. There is an obvious decrease in the sensitivity of the tests when the localization of the cyst exclusively pulmonary; in these cases the RAST test was positive in only 50%, and the degranulation test in 77.7%.