[Prevalence, knowledge and control of arterial hypertension in vulnerable neighborhoods of Argentina: A Cross-sectional Study]. / Estudio de prevalencia, conocimiento y control de la hipertensión arterial en barrios vulnerables de Argentina.

INTRODUCTION: Hypertension (HTN) represents the primary individual risk factor, contributing significantly to the global burden of cardiovascular diseases (CVD). In our country, epidemiological research has highlighted substantial variations in the prevalence of these risk factors across different populations. However, there is a lack of epidemiological studies assessing exclusive cardiovascular risk factors within vulnerable neighborhoods characterized by extremely limited economic resources, sociocultural challenges, and inadequate healthcare access. METHODS: A multicenter cross-sectional observational study was conducted among individuals residing in economically deprived and marginalized communities, including informal settlements and underprivileged neighborhoods. Simple random sampling of households was employed. Blood pressure measurements, anthropometric assessments, and epidemiological, economic, and sociocultural questionnaires were administered. Results encompass prevalence rates, awareness levels, and blood pressure control across diverse regions. Logistic regression was utilized to identify independent variables influencing primary outcomes. RESULTS: A total of 989 participants were analyzed. The overall prevalence of hypertension was 48.2%. About 82% had a body mass index (BMI) >25. Approximately 45.3% had less than 6 years of formal education. Independent association was established between education levels below 6 years and higher hypertension prevalence. Among hypertensive individuals, 44% were unaware of their condition, with only 17.2% achieving control, correlated with having health insurance and a higher educational background. Merely 24% were receiving combined therapy. CONCLUSION: The prevalence of hypertension within vulnerable neighborhoods is alarmingly high, surpassing rates in other social strata. Knowledge, treatment, and control levels of hypertension are suboptimal, comparable to other populations. Inadequate use of combination therapy was observed. This study underscores the urgent need for targeted interventions addressing cardiovascular risk factors in poor areas to mitigate the burden of CVD.

Active and passive microrheology with large tracers in hard colloids.

The dynamics of a tracer particle in a bath of quasi-hard colloidal spheres is studied by Langevin dynamics simulations and mode coupling theory (MCT); the tracer radius is varied from equal to up to seven times larger than the bath particles radius. In the simulations, two cases are considered: freely diffusing tracer (passive microrheology) and tracer pulled with a constant force (active microrheology). Both cases are connected by linear response theory for all tracer sizes. It links both the stationary and transient regimes of the pulled tracer (for low forces) with the equilibrium correlation functions; the velocity of the pulled tracer and its displacement are obtained from the velocity auto-correlation function and the mean squared displacement, respectively. The MCT calculations give insight into the physical mechanisms: At short times, the tracer rattles in its cage of neighbours, with the frequency increasing linearly with the tracer radius asymptotically. The long-time tracer diffusion coefficient from passive microrheology, which agrees with the inverse friction coefficient from the active case, arises from the transport of transverse momentum around the tracer. It can be described with the Brinkman equation for the transverse flow field obtained in extension of MCT, but cannot be recovered from the MCT kernel coupling to densities only. The dynamics of the bath particles is also studied; for the unforced tracer the dynamics is unaffected. When the tracer is pulled, the velocity field in the bath follows the prediction of the Brinkman model, but different from the case of a Newtonian fluid.

Modeling of post-traumatic epilepsy and experimental research aimed at its prevention

Research on the prevention of post-traumatic epilepsy (PTE) has seen remarkable advances regarding its physiopathology in recent years. From the search for biomarkers that might be used to indicate individual susceptibility to the development of new animal models and the investigation of new drugs, a great deal of knowledge has been amassed. Various groups have concentrated efforts in generating new animal models of traumatic brain injury (TBI) in an attempt to provide the means to further produce knowledge on the subject. Here we forward the hypothesis that restricting the search of biomarkers and of new drugs to prevent PTE by using only a limited set of TBI models might hamper the understanding of this relevant and yet not preventable medical condition.

Modeling of post-traumatic epilepsy and experimental research aimed at its prevention.

Research on the prevention of post-traumatic epilepsy (PTE) has seen remarkable advances regarding its physiopathology in recent years. From the search for biomarkers that might be used to indicate individual susceptibility to the development of new animal models and the investigation of new drugs, a great deal of knowledge has been amassed. Various groups have concentrated efforts in generating new animal models of traumatic brain injury (TBI) in an attempt to provide the means to further produce knowledge on the subject. Here we forward the hypothesis that restricting the search of biomarkers and of new drugs to prevent PTE by using only a limited set of TBI models might hamper the understanding of this relevant and yet not preventable medical condition.

Dynamics and friction of a large colloidal particle in a bath of hard spheres: Langevin dynamics simulations and hydrodynamic description.

The analysis of the dynamics of tracer particles in a complex bath can provide valuable information about the microscopic behavior of the bath. In this work, we study the dynamics of a forced tracer in a colloidal bath by means of Langevin dynamics simulations and a theory model within continuum mechanics. In the simulations, the bath is comprised of quasihard spheres with a volume fraction of 50% immersed in a featureless quiescent solvent, and the tracer is pulled with a constant small force (within the linear regime). The theoretical analysis is based on the Navier-Stokes equation, where a term proportional to the velocity arises from coarse-graining the friction of the colloidal particles with the solvent. As a result, the final equation is similar to the Brinkman model, although the interpretation is different. A length scale appears in the model, k_{0}^{-1}, where the transverse momentum transport crosses over to friction with the solvent. The effective friction coefficient experienced by the tracer grows with the tracer size faster than the prediction from Stokes's law. Additionally, the velocity profiles in the bath decay faster than in a Newtonian fluid. The comparison between simulations and theory points to a boundary condition of effective partial slip at the tracer surface. We also study the fluctuations in the tracer position, showing that it reaches diffusion at long times, with a subdiffusive regime at intermediate times. The diffusion coefficient, obtained from the long-time slope of the mean-squared displacement, fulfills the Stokes-Einstein relation with the friction coefficient calculated from the steady tracer velocity, confirming the validity of the linear response formalism.

Variables asociadas a complicaciones de la punción con aguja fina frente a biopsia con aguja gruesa de las lesiones pulmonares / Variables associated with complications of fine needle puncture against core needle biopsy of pulmonary injuries

Introducción. El cáncer de pulmón es la primera causa de muerte por cáncer contando con terapias específicas que exigen identificar estructuras moleculares; por ello se utiliza más biopsia aguja gruesa, pudiendo aumentar el riesgo de complicaciones. El objetivo es comparar tasa de complicaciones de punción aguja fina (PAAF) frente a biopsia aguja gruesa (BAG) y analizar variables asociadas. Material y método. Análisis retrospectivo observacional de 146 pacientes con lesiones pulmonares periféricas, practicando PAAF o BAG guiada con técnicas de imagen. El periodo de estudio (marzo 2012-septiembre 2013), durante la primera mitad se realizó PAAF y durante la segunda BAG. Se calculó la tasa de complicaciones y se analizaron variables relativas al tamaño y localización lesión, técnica y presencia de enfisema. El estudio estadístico se realizó mediante un análisis univariado seguido de un modelo de regresión logística. Resultados. Se realizó PAAF en 66 pacientes (45,2%) y BAG en 80 (54,8%). Tasa global complicaciones 36,3% (53 casos), siendo neumotórax la más frecuente 43 casos (29,5%). La tasa de complicaciones fue menor en BAG que PAAF (28,8% vs 45,5%) (p= 0,037) en análisis univariado. En análisis multivariado las variables que asociaron mayor probabilidad complicaciones fueron: número pases ≥ 3 (OR 0,57), tamaño lesión < 30 mm (OR 3,45) y distancia lesión-pleura > 15 mm (OR 0,94). Conclusiones. Los factores que asociaron de forma independiente complicaciones fueron tamaño lesión, distancia lesión-pleura y número pases. La menor tasa complicaciones de BAG se explica por el menor número de pases realizados

Introduction. Lung cancer is the leading cause of cancer death, with specific therapies that require identification of molecular structures; therefore, a core needle biopsy is used, which can increase the risk of complications. The objective is to compare the rate of complications of fine needle puncture (FNP) versus core needle biopsy (CNB) and analyze associated variables. Material and method. Retrospective observational analysis of 146 patients with peripheral pulmonary lesions, practicing FNP or CNB guided with imaging techniques. Study period (March 2012-September 2013), during the first half FNP was carried out and during the second CNB. The complication rate was calculated and variables related to size and location of the lesion, technique and presence of emphysema were analyzed. The statistical study was carried out through a univariate analysis followed by a logistic regression model. Results. FNP was performed in 66 patients (45.2%) and CNB in 80 (54.8%). Overall rate complications 36.3% (53 cases) with pneumothorax being the most frequent 43 cases (29.5%). The complication rate was lower in CNB than FNP (28.8% vs 45.5%) (p= 0.037) in univariate analysis. In multivariate analysis, variables that associated the highest probability of complications were: number of passes ≥ 3 (OR 0.57), lesion size < 30 mm (OR 3.45) and lesion-pleura distance > 15 mm (OR 0.94). Conclusions. Factors that independently associated complications were lesion size, lesion-pleura distance and number of passes. The lower complication rate of BAG is explained by lower number of passes made

TomoEED: fast edge-enhancing denoising of tomographic volumes.

Summary: TomoEED is an optimized software tool for fast feature-preserving noise filtering of large 3D tomographic volumes on CPUs and GPUs. The tool is based on the anisotropic nonlinear diffusion method. It has been developed with special emphasis in the reduction of the computational demands by using different strategies, from the algorithmic to the high performance computing perspectives. TomoEED manages to filter large volumes in a matter of minutes in standard computers. Availability and implementation: TomoEED has been developed in C. It is available for Linux platforms at http://www.cnb.csic.es/%7ejjfernandez/tomoeed. Supplementary information: Supplementary data are available at Bioinformatics online.

Análisis multiciiterio del estado de las pasturs de la hacienda Ganadera garcíía abajo en corinto (cauca, Colombia) / Multi-critera annalysis of grasses of the fam livestock garcia abajo in corrinto (cauca, Colombia)

La evaluación de pasturas utilizando criterios múltiples constituye una herramienta de importancia para la toma de decisiones en el manejo de sistemas ganaderos sostenibles. El objetivo fue construir un índice de estado con base en indicadores productivos y biológicos de los componentes herbáceo y leñoso para tipificar 50 potreros de una explotación ganadera de la Hacienda García Abajo, departamento del Cauca, Colombia. Se levantó información de nueve variables que describen factores incidentes en la producción (área de potreros, edad de la pastura, topografía, árboles y cobertura de dosel), la composición botánica (leguminosas, arvenses, especies de gramíneas) e indicadores de cantidad y calidad de las pasturas (biomasa forrajera y color). Siete de estas variables fueron medidas y calificadas con los uso de una herramienta multicriterio. Mediante estadística multivariada se realizó una tipología de potreros. El conglomerado C1 agrupa los 17 potreros con mayor tiempo de establecimiento, mientras C2 corresponde al de menor cantidad de potreros, los cuales son pasturas jóvenes. C3 agrupa el mayor número de potreros (25), los que a su vez tienen la mayor extensión promedio. C2 fue el conglomerado con mayor producción de biomasa y el que presentó menor porcentaje de vegetación espontánea. En conclusión, el análisis multicriterio para evaluar pasturas permite tomar decisiones y realizar juicios fundamentados sobre diferentes valoraciones, lo cual hace que el diagnóstico sea más acertado y mejor la formulación de soluciones con base en referentes endógenos, a fin de ir mejorando progresivamente el manejo de la finca.

Evaluation of pasture, based on a multicriteria approach, is an important issue for decision making in the design of sustainable farming systems. The aim was to build a state index, based on production and biological indicators of pasture in 50 paddocks of a farm estate Garcia Abajo, located on department of Cauca, Colombia. Nine variables describing incidents factors in production factors (area of pasture, pasture age, topography, trees and canopy cover), the botanical composition (legumes, weeds, grass species) and indicators of quantity and quality of pastures (forage biomass and color) was measured and ranked with the use of a multi-criteria tool. Using multivariate statistics, a typology of pastures was performed. The C1 cluster groups the 17 paddocks longer listing, while C2 corresponds to fewer paddocks, which are young pastures. C3 contains the largest number of pastures (25), which in turn have the largest area averages. C2 fuel conglomerate highest biomass production, and has the lowest percentage of spontaneous vegetation. In conclusion, the multi-criteria analysis to evaluate pastures allows the decision maker to make judgments based on different ratings, which makes diagnosis and formulating solutions, based on endogenous concerning more successful.

[Pulmonary silicoproteinosis. A case of prolonged survival]. / Silicoproteinosis pulmonar. Un caso con supervivencia prolongada

Alveolar silicoproteinosis is a very rare form of silicosis that can develop after a latency period of between a few months and 5 years after the first exposure to silica, and courses invariably, with rapid deterioration of lung function, without an effective response to treatment. Because of its rarity and its unique outcome, the case is presented of a 55 year old woman, diagnosed with alveolar silicoproteinosis in our hospital, who improved by removing the occupational exposure to silica dust and remains stable with no radiological or lung function worsening four years after diagnosis of the disease. To our knowledge, this is the first case of alveolar silicoproteinosis that had a good outcome.

Hybrid computing: CPU+GPU co-processing and its application to tomographic reconstruction.

Modern computers are equipped with powerful computing engines like multicore processors and GPUs. The 3DEM community has rapidly adapted to this scenario and many software packages now make use of high performance computing techniques to exploit these devices. However, the implementations thus far are purely focused on either GPUs or CPUs. This work presents a hybrid approach that collaboratively combines the GPUs and CPUs available in a computer and applies it to the problem of tomographic reconstruction. Proper orchestration of workload in such a heterogeneous system is an issue. Here we use an on-demand strategy whereby the computing devices request a new piece of work to do when idle. Our hybrid approach thus takes advantage of the whole computing power available in modern computers and further reduces the processing time. This CPU+GPU co-processing can be readily extended to other image processing tasks in 3DEM.

A matrix approach to tomographic reconstruction and its implementation on GPUs.

Electron tomography allows elucidation of the molecular architecture of complex biological specimens. Weighted backprojection (WBP) is the standard reconstruction method in the field. In this work, three-dimensional reconstruction with WBP is addressed from a matrix perspective by formulating the problem as a set of sparse matrix-vector products, with the matrix being constant and shared by all the products. This matrix approach allows efficient implementations of reconstruction algorithms. Although WBP is computationally simple, the resolution requirements may turn the tomographic reconstruction into a computationally intensive problem. Parallel systems have traditionally been used to cope with such demands. Recently, graphics processor units (GPUs) have emerged as powerful platforms for scientific computing and they are getting increasing interest. In combination with GPU computing, the matrix approach for WBP exhibits a significant acceleration factor compared to the standard implementation.

Vectorization with SIMD extensions speeds up reconstruction in electron tomography.

Electron tomography allows structural studies of cellular structures at molecular detail. Large 3D reconstructions are needed to meet the resolution requirements. The processing time to compute these large volumes may be considerable and so, high performance computing techniques have been used traditionally. This work presents a vector approach to tomographic reconstruction that relies on the exploitation of the SIMD extensions available in modern processors in combination to other single processor optimization techniques. This approach succeeds in producing full resolution tomograms with an important reduction in processing time, as evaluated with the most common reconstruction algorithms, namely WBP and SIRT. The main advantage stems from the fact that this approach is to be run on standard computers without the need of specialized hardware, which facilitates the development, use and management of programs. Future trends in processor design open excellent opportunities for vector processing with processor's SIMD extensions in the field of 3D electron microscopy.

Topiramate for the treatment of juvenile myoclonic epilepsy

OBJECTIVE: The aim of this study was to evaluate the efficacy and tolerability of topiramate (TPM) in juvenile myoclonic epilepsy (JME). METHOD: We assessed seizure control and adverse effects of TPM in 22 patients (18 females) aged 13 to 53 years. Target TPM dosage was up to 200 mg/day. The patients were subdivided into 3 groups: those treated with seizure control plus side effects (n=4); treated with non-controlled seizures (n=15) and with JME newly diagnosed (n=3). RESULTS: Sixteen patients completed the first year of the follow-up. Generalized tonic-clonic seizures were completely controlled in 10 (62.5%); more than 50% of reduction in 4 (25.0%) and less than 50% in 2 (12.5%). Myoclonia were controlled in 11 (68.8%) and persisted in 5 (31.2%) patients. Absence seizures were present in 5 (22.7%) of whom 2 (9.0%) showed more than 50% of seizure reduction while 3 (13.6%) presented worsening. Discontinuations were due to inadequate seizure control and adverse events (N=4), low compliance and loss of follow-up (N=2) and subject choice (N=1). CONCLUSION: TPM showed to be an effective and well-tolerated drug in the treatment of JME. Although frequently observed, TPM side effects were tolerable and the drug could be maintained in the majority of patients.

OBJETIVO: Avaliar a eficácia e tolerabilidade do topiramato (TPM) na epilepsia mioclônica juvenil (EMJ). MÉTODO: Avaliamos a resposta terapêutica e efeitos colaterais do TPM em 22 pacientes (18 mulheres) com idades entre 13 e 53 anos. A dose alvo utilizada foi até 200 mg/dia. Os pacientes foram divididos em 3 grupos no início do tratamento: aqueles com controle das crises mas que apresentavam efeitos colaterais (n=4); com crises não controladas (n=15) e com EMJ recém diagnosticada (n=3). RESULTADOS: Dezesseis pacientes completaram o primeiro ano de acompanhamento. Crises tônico-clonicas generalizadas foram completamente controladas em 10 (62,5%), tiveram redução maior de 50% em 4 (25,0%) e menor de 50% em 2 (12,5%). Mioclonias foram controladas em 11 (68,8%) e persistiram em 5 (31.2%) pacientes. As crises de ausências, presentes em 5 (22,7%) pacientes, tiveram redução maior do que 50% em 2 (9,0%) e agravamento em 3 (13,6%). A retirada do estudo foi devida principalmente ao controle inadequado das crises e efeitos colaterais indesejáveis (n=4), pouca adesão e perda do seguimento (n=2) e escolha do paciente (n=1). CONCLUSÃO: TPM foi considerada droga eficaz e bem tolerada no tratamento da EMJ. Apesar de freqüentemente observados, os efeitos colaterais do TPM foram toleráveis e a medicação pode ser mantida na maioria dos pacientes.

Differential infectivity and immunopathology in murine experimental infections by two natural clones belonging to the Trypanosoma cruzi I lineage.

Immunopathology of Chagas' disease in Balb/c mice infected with 2 Trypanosoma cruzi clones, belonging to the T. cruzi I lineage and presenting different in vitro virulence (P/209 cl1 > SO34 c14) was compared. In the acute phase, evading mechanisms such as parasite-induced lymphocyte polyclonal activation and T cell immunosuppression were higher in mice infected with the clone giving a higher parasitaemia (P/209 cl1). A similar increase of non-specific isotypes was observed in both infections with IgG2a prevalence. Interestingly, CD8+ cell hypercellularity and lymphocyte immunosuppression were observed during the chronic phase (245 days post-infection) in mice infected by the most virulent clone. In the same way, the parasite-specific antibody response was more intense in P/209 cl1-infected mice over the acute phase. During the chronic phase this response remarkably dropped down in SO34 cl4-infected mice exclusively. Finally, P/209 cl1-infected mice presented a more severe inflammation and tissue damage in heart and quadriceps than SO34 cl4-infected mice. This comparative study showed differences between the two clones: a higher virulence in vivo being clearly associated with a greater ability to induce evasion mechanisms and severe tissue damage.

High infection rates of Triatoma dimidiata are associated with low levels of Trypanosoma cruzi seroprevalence in Pedro Carbo, Ecuador. Use of a tc24 gene-based PCR approach.

In control programs for vectorial transmission of Chagas' disease, conventional microscopic procedures are generally performed to determine baseline levels of infectivity of vectors. Reported here are data using Polymerase Chain Reaction in the detection of Trypanosoma cruzi in Triatoma dimidiata, one of the principal vectors of Chagas' disease in Ecuador. The microscopy and PCR techniques showed a high percentage of vector infection in Pedro Carbo, province of Guayas (Ecuador), with 44.16% and 46.13% positive insects, respectively. This contrasted with the very low Chagas seropositivity recorded (0.5%). Since T. dimidiata was the only vector of the Chagas' disease found in Pedro Carbo and looking at the vector behavior, our data suggest that despite the high T. dimidiata infection, the low Chagas seropositivity detected is closely associated with the epidemiological and ecological context of T. dimidiata in Pedro Carbo.

Trypanosoma cruzi isoenzyme variability in Ecuador: first observation of zymodeme III genotypes in chronic chagasic patients.

We have analysed by multilocus enzyme electrophoresis (MLEE) at 21 genetic loci 10 Trypanosoma cruzi stocks isolated from chronic chagasic patients and 3 stocks isolated from Triatoma dimidiata collected in human habitats from the coastal part of Ecuador (all stocks isolated in August-December 1998). Isoenzyme profiles were compared to those of 4 laboratory-cloned stocks representing the major phylogenetic subdivisions of T. cruzi. This parasite's genetic variability in Ecuador proved to be considerable, even in this limited sample, since all main isoenzyme genotypes were recorded. Four stocks from patients were identical at all loci to the reference stock MNcl2 ('major clonet #39'; T. cruzi II) isolated in Chile. The 3 stocks isolated from T. dimidiata were closely related to the formerly described zymodeme I (T. cruzi I). Finally, 3 stocks from chronic chagasic patients (one with an asymptomatic form, 2 with a cardiac-digestive form) were closely related to the formerly described zymodeme III (presently not classified in either T. cruzi I or T. cruzi II). This is the first observation of this category of T. cruzi genotypes in chronic chagasic patients. In the past it was recorded only in acute patients, wild mammals and wild triatomine bugs. The epidemiological implications of these results are discussed.

Serial EEG during human status epilepticus: evidence for PLED as an ictal pattern.

OBJECTIVE: To analyze the relationship between periodic lateralized epileptiform discharges (PLED) and status epilepticus (SE), to evaluate the relationship between mortality and periodic patterns, and to determine whether a stereotypic sequence of EEG patterns exists during human SE. METHODS: The authors performed a prospective clinical and electrographic study comprising 62 episodes of SE, 55 patients, and 254 ictal/postictal EEG recordings. Serial daily EEG were obtained in all cases. RESULTS: Partial SE was the predominant clinical type. Four distinct ictal EEG patterns were identified: intermittent EEG seizures (IES), merging EEG seizures (MES), continuous ictal discharges (CID), and periodic epileptiform discharges (PED) which could be lateralized (PLED) or bilateral (PBED). IES was the most common ictal pattern. In the same record, only one combination of ictal patterns was observed corresponding to an association of PLED or PBED and MES pattern. Serial EEG demonstrated that approximately one-third of SE resolved before the second EEG, another one-third persisted and maintained the same ictal pattern throughout the entire evolution, and the final one-third showed variable ictal EEG patterns. PLED were also unequivocally associated with epileptic seizures, and in some patients were the initial ictal pattern. CONCLUSION: PLED can be an ictal pattern; and, in contrast to previous observations, no stereotyped sequence of ictal EEG patterns was found. PLED/PBED were not a terminal ictal pattern in every case, and outcome was more related to age and etiology than to specific ictal EEG patterns.

[Myocardial perfusion SPET in the detection of coronary artery disease in orthotopic heart transplantation]. / SPET de perfusión miocárdica en la detección de enfermedad arterial coronaria en el trasplante ortotópico de corazón.

The incidence of atherosclerosis of the heart transplant in long term survivors is 38% at 5 years. In the present work, myocardial perfusion 201Tl-SPET was assessed as a non-invasive diagnostic method for the detection of postransplant coronary artery disease, as well as its efficiency with regard to other techniques. Twenty patients, aged (47 +/- 9) years old, who underwent heart transplantation at least 3 years earlier, were studied by 201Tl-SPET. Qualitative and quantitative analysis of the images were performed. It was found ischemia in 6 patients, 4 of them asymptomatics. In 5 of the 6 positive cases by SPET coronary stenosis was found by angiography. Kappa coefficient and percent of agreement were k = 0. 76 and Pe = 90%, respectively. There were no relationships among rejection crisis, sepsis by cytomegalovirus and coronary artery disease detected by using 201Tl-SPET (p > 0.05). The most relevant risk factors in the sample were hypertension and hyperlipidemia. Two patients died because of coronary artery disease. It was confirmed by necropsy findings. These results suggest that thallium-201 myocardial perfusion tomography could be useful to detect coronary artery disease in the transplanted heart.

[Colitis induced by a food allergen. A report of 20 cases]. / Colitis inducida por alergeno alimentario. Presentación de 20 casos.

In the last years, we have appreciated a descending number of classic enteral food-protein intolerance and cases of colitis related to food proteins are increasing. In this study, 20 cases of food protein colitis (mainly related to cow's milk) are reviewed and clinical, endoscopic and histological aspects are analyzed. We found that the age at the time of the first consultation was approximately 1.5 months, with males predominating. The main symptom was bloody diarrhoea. Other causes such as perianal fissure or infectious gastroenteritis were excluded. The infants were fed breast milk and/or cow's milk formula. Some patients had low hemoglobin, but low serum albumin was infrequent. The colonoscopy showed erythema and, in some cases, loss of vascular pattern, ulcerations or bleeding. The main histological finding was an increased number of eosinophils. There was a favorable response to the dietary change. After 6 months, all of the provocations done were negative. We conclude that food-protein intolerance is one of the most probable causes of bloody stools in a young infant. Colonoscopy and a histopathological study of at least three biopsy pieces are necessary for the diagnosis. The treatment is the exclusion of the offending protein from the diet.

Serologic diagnosis of Oestrus ovis (Diptera:Oestridae) in naturally infested sheep.

Sera from eighteen control sheep supposed to be free from parasitism by Oestrus ovis Linnaeus, 1761, and from 100 sheep raised in an enzootic area of O.ovis infestations were tested to detect anti-Oestrus antibodies by double immunodiffusion (DD) and indirect haemagglutination (IH) tests with somatic crude antigens from first (L1), second (L2) and third (L3) instar of O.ovis larvae. At necropsy, eighty-eight out of 100 sheep from the O.ovis infested area were found to be parasitized while the eighteen control ovines did not show Oestrus larvae. Examination of the sera from the parasitized sheep by DD showed positive results of 42% for L1, 59% for L2 and 18% for L3. Screening the sera with IH gave sensitivities of 100% for L1, 100% for L2 and 97.7% for L3. Sheep, naturally parasitized by gastrointestinal nematodes, presented no cross immune reactions in DD tests with the three larval stages of O.ovis or with L2 larvae in IH tests.