Hemorragia digestiva en neonato con uncinarias, Hospital Nacional San Bartolomé: Reporte de caso / Gastrointestinal bleeding in newborn with hookworm, National Hospital San Bartolome: Case report

Se presenta un caso de hemorragia digestiva por uncinariasis en una recién nacida de 27 días, procedente de la comunidad de Tangoshiri ubicada en la provincia de La Convención, en el departamento de Cuzco, quien ingresa al servicio de neonatología del Hospital Nacional Docente San Bartolomé de la ciudad de Lima, por anemia severa descompensada. Presentó, desde los 4 días de nacida, melena que se incrementa a la tercera semana de vida, con hematocrito de 12% por lo que se hospitaliza, recibiendo transfusión sanguínea y al persistir la hemorragia digestiva, se le realiza endoscopia digestiva alta evidenciándose múltiples larvas de Ancylostoma duodenal. Se le dio tratamiento con mebendazol a ella y a la madre con negativización de los exámenes de heces para la presencia del parásito.

We present the case of gastrointestinal bleeding uncinariasis in a newborn baby of 27 days old from anindigenous town of Tangoshiri, located in the province of La Convencion, department of Cuzco, who enters to the service of neonatology National Teaching Hospital San Bartolome in Lima, Peru, with decompensated severe anemia. The baby has melena since the fourth day of his birth, which increased in the third week of life, with hematocrit of 12%. She was hospitalized, receiving blood transfusion and she continue with gastrointestinal bleeding, so she underwent an upper endoscopy that showed multiple larvae Ancylostoma duodenale. She and her mother were treated with mebendazole. Afterwords they had stool examinations without the presence of the parasite.

Pain Intensity and Misconceptions Among Hospice Patients With Cancer and Their Caregivers: Status After 2 Decades.

There is little evidence about barriers to pain management or their relationships with pain outcomes of hospice patients with cancer. The purpose of the study was to determine the barriers reported by hospice patients with cancer and their caregivers and the relationships with demographic characteristics and the patients' pain. In this cross-sectional study, we used selected baseline data from an ongoing randomized clinical trial of patient and lay caregiver dyads receiving home-level hospice care. Participants used an Internet-enabled tablet to complete the valid, reliable measures of pain intensity, pain management barriers (Barriers Questionnaire 13 items [BQ-13]), and demographic characteristics. The responses indicate that the 2 areas of highest concern (mean scores >3) to both patients and caregivers were "pain means disease progression" and "constipation." Additionally, 3 other areas of highest concern (mean scores >3) to caregivers were "addiction" pain medicine causing "one to do embarrassing things" and "confusion." The mean BQ-13 scores ranged from 0.2 to 4.9 and averaged 2.6 ± 0.9 for the patients and ranged from 0.5 to 4.7 and averaged 2.7 ± 0.9 for the caregivers. Mean barrier scores remain high and were not different between patients and their caregivers or significantly related to the patients' pain intensity. However, there were differences in race, ethnic, and hospice setting in the barrier scores. Patients with Hispanic heritage reported higher barrier scores than non-Hispanic patients. Together, these findings not only support prior research findings but also contribute new insights about pain intensity and pain barriers that are relevant to hospices serving minorities with cancer.

Kinematic Bézier Maps.

The kinematics of a robot with many degrees of freedom is a very complex function. Learning this function for a large workspace with a good precision requires a huge number of training samples, i.e., robot movements. In this paper, we introduce the Kinematic Bézier Map (KB-Map), a parameterizable model without the generality of other systems but whose structure readily incorporates some of the geometric constraints of a kinematic function. In this way, the number of training samples required is drastically reduced. Moreover, the simplicity of the model reduces learning to solving a linear least squares problem. Systematic experiments have been carried out showing the excellent interpolation and extrapolation capabilities of KB-Maps and their relatively low sensitivity to noise.

Rigid-CLL: avoiding constant-distance computations in cell linked-lists algorithms.

Many of the existing molecular simulation tools require the efficient identification of the set of nonbonded interacting atoms. This is necessary, for instance, to compute the energy values or the steric contacts between atoms. Cell linked-lists can be used to determine the pairs of atoms closer than a given cutoff distance in asymptotically optimal time. Despite this long-term optimality, many spurious distances are anyway computed with this method. Therefore, several improvements have been proposed, most of them aiming to refine the volume of influence for each atom. Here, we suggest a different improvement strategy based on avoiding to fill cells with those atoms that are always at a constant distance of a given atom. This technique is particularly effective when large groups of the particles in the simulation behave as rigid bodies as it is the case in simplified models considering only few of the degrees of freedom of the molecule. In these cases, the proposed technique can reduce the number of distance computations by more than one order of magnitude, as compared with the standard cell linked-list technique. The benefits of this technique are obtained without incurring in additional computation costs, because it carries out the same operations as the standard cell linked-list algorithm, although in a different order. Since the focus of the technique is the order of the operations, it might be combined with existing improvements based on bounding the volume of influence for each atom.

Pulp and paper from vine shoots: neural fuzzy modeling of ethylene glycol pulping.

The influence of operational variables in the pulping of vine shoots by use of ethylene glycol [viz. temperature (155-185 degrees C), cooking time (30-90 min) and ethylene glycol concentration (50-70% v/v)] on the properties of the resulting pulp (viz. yield, kappa number and viscosity) and paper sheets (breaking length, stretch, burst index, tear index and brightness) was studied. A central composite factorial design was used in conjunction with the software ANFIS Edit Matlab 6.5 to develop fuzzy neural model that reproduced the experimental results of the dependent variables with errors less than 5%. The model is therefore effective with a view to simulating the ethylene glycol pulping process.

Ethyleneglycol pulp from tagasaste.

In this work, we examined the influence of operational variables [viz. Ethyleneglycol concentration (50-70%), temperature (155-185 degrees C), time (30-90 min) and number of PFI beating revolutions (500-1500)] in the ethyleneglycol pulping of tagasaste (Chamaecytisus proliferus) on pulp yield and the breaking length, stretch, burst index, tear index and brightness of paper sheets formed from it. Application of a fuzzy neural network model in combination with an experimental factorial design allowed the results for the dependent variables to be predicted as a function of the operating conditions used with errors less than 15% in all cases. The operating conditions of choice provided pulp with a high yield (56.85%) and a low brightness (22.51%) which may thus be useful to obtain non-white paper.

House-level risk factors for triatomine infestation in Colombia.

BACKGROUND: Chagas disease, transmitted domestically by triatomine bugs, is the most important vector-borne disease in Latin America. The association between triatomine infestation and housing characteristics was investigated based on a standardized survey in 41 971 houses in 15 Departments in Colombia. METHODS: Multivariate logistic regression was used to test for associations of two highly correlated infestation measures of infestation (householders reporting having seen triatomines inside the house, and sending triatomines to the survey team), with 15 household-level risk factors. Risks were measured relative to a reference category of houses with up to three inhabitants, area up to 50 m(2), unplastered adobe walls, thatch roof and no outbuildings or domestic animals. RESULTS: The probability of seeing triatomines was highest for households with over seven inhabitants (OR = 1.24, 95% CI 1.11-1.39), overhead storage space (OR = 1.16, 95% CI 1.03-1.32), grain shed (OR = 1.25, 95% CI 1.02-1.52), cats (OR = 1.27, 95% CI 1.14-1.42) and pigs (OR = 1.16, 95% CI 1.03-1.30). Lowest risks were in houses with wooden walls (OR = 0.46, 95% CI 0.34-0.61), fully plastered walls (OR = 0.78, 95% CI 0.68-0.88), roofs made of tiles (OR = 0.51, 95% CI 0.33-0.78) and flagstone floors (OR = 0.57, 95% CI 0.42-0.76). Results for householders returning triatomines support this set of risk factors, but with wider confidence intervals. CONCLUSIONS: Surveillance of a few easily assessed household characteristics provides an accurate, rapid assessment of house-level variation in risk. Measured effect sizes for specific structural characteristics could be used to maximize the cost-effectiveness of programmes to reduce vector infestation and interrupt Chagas disease transmission by improving house quality.

Comparison of polynomial and neural fuzzy models as applied to the ethanolamine pulping of vine shoots.

The influence of operational variables in the pulping of vine shoots by use of ethanolamine [viz. temperature (155-185 degrees C), cooking time (30-90min) and ethanolamine concentration (50-70% v/v)] on the properties of the resulting pulp (viz. yield, kappa index, viscosity and drainability) was studied. A central composite factorial design was used in conjunction with the software BMDP and ANFIS Edit Matlab 6.5 to develop polynomial and fuzzy neural models that reproduced the experimental results of the dependent variables with errors less than 10%. Both types of models are therefore effective with a view to simulating the ethanolamine pulping process. Based on the proposed equations, the best choice is to use values of the operational valuables resulting in near-optimal pulp properties while saving energy and immobilized capital on industrial facilities by using lower temperatures and shorter processing times. One combination leading to near-optimal properties with reduced costs is using a temperature of 180 degrees C and an ethanolamine concentration of 60% for 60min, to obtain pulp with a viscosity of 6.13% lower than the maximum value (932.8ml/g) and a drainability of 5.49% lower than the maximum value (71 (o)SR).

Chromosomal variation and genome size support existence of cryptic species of Triatoma dimidiata with different epidemiological importance as Chagas disease vectors.

The wide geographical distribution of Triatoma dimidiata, one of the three major vectors of Chagas disease, ranges from Mexico to northern Peru. Since this species occupies a great diversity of artificial and natural ecotopes, its eradication is extremely difficult. In order to assist control efforts, we used chromosome analyses and DNA amount as taxonomic markers to study genetic variability in populations of T. dimidiata from Mexico, Guatemala, El Salvador and Colombia. We differentiated three groups or cytotypes defined by characteristic chromosome C-banding patterns and genome size measured by flow cytometry. The three cytotypes are restricted to different geographic locations. Cytotype 1 occurs in Mexico (excluding Yucatán), Guatemala (excluding Petén), El Salvador and Colombia. Cytotype 2 occurs in Yucatán and cytotype 3 occurs in Petén. Cytotype 1, commonly associated with domestic and peridomestic environments but also inhabiting sylvatic ecotopes, is the most widespread and with major epidemiological significance. In contrast, the Yucatán cytotype inhabits wild ecotopes but increasingly enters houses, while the Petén cytotype appears exclusively sylvatic. We suggest that these cytotypes represent cryptic species of T. dimidiata with different epidemiological relevance as Chagas disease vectors. Poor ability to colonize human dwellings, together with their restricted geographic distribution, indicate that the Yucatán and Petén putative species probably have much less epidemiological significance than cytotype 1. Thus, the genetic markers we describe are powerful tools to differentiate cryptic species in T. dimidiata with different epidemiological significance, contributing to planning the most effective control measures.

A path planning approach for computing large-amplitude motions of flexible molecules.

MOTIVATION: Motion is inherent in molecular interactions. Molecular flexibility must be taken into account in order to develop accurate computational techniques for predicting interactions. Energy-based methods currently used in molecular modeling (i.e. molecular dynamics, Monte Carlo algorithms) are, in practice, only able to compute local motions while accounting for molecular flexibility. However, large-amplitude motions often occur in biological processes. We investigate the application of geometric path planning algorithms to compute such large motions in flexible molecular models. Our purpose is to exploit the efficacy of a geometric conformational search as a filtering stage before subsequent energy refinements. RESULTS: In this paper two kinds of large-amplitude motion are treated: protein loop conformational changes (involving protein backbone flexibility) and ligand trajectories to deep active sites in proteins (involving ligand and protein side-chain flexibility). First studies performed using our two-stage approach (geometric search followed by energy refinements) show that, compared to classical molecular modeling methods, quite similar results can be obtained with a performance gain of several orders of magnitude. Furthermore, our results also indicate that the geometric stage can provide highly valuable information to biologists. AVAILABILITY: The algorithms have been implemented in the general-purpose motion planning software Move3D, developed at LAAS-CNRS. We are currently working on an optimized stand-alone library that will be available to the scientific community.

[Esophageal varices hemorrhage. Endoscopic treatment]. / Hemorragia por várices esofágicas. Tratamiento endoscópico.

The patient with bleeding esophageal varices represents always a challenge to the medical team carrying a high mortality in spite of advances in pharmacologic and endoscopic treatments, notwithstanding that bleeding is just one added complication in the setting of the ailments of portal hypertension. Sclerotherapy, once the treatment of choice, has been displaced in recent year by variceal ligature, with less morbidity and equal success rate, both of them being technically simple. In the same way, variceal ligature has displaced sclerotherapy as treatment for secondary prophylaxis, with less complications and less sessions needed for variceal erradication and bleeding prevention. On the other hand, sclerotherapy is not indicated for patients with large varices, while ligature competes with pharmacologic treatment, some people suggesting the superiority of ligature because of better patient compliance, although probably the best option would be a combination of both. Thus, endoscopic treatment has an important role in this clinical situation, both for diagnosis as for management of active bleeding and primary prophylaxis.

Comparison of four serological tests for the diagnosis of Chagas disease in a Colombian endemic area.

The performance of 4 serological tests for the diagnosis of Chagas disease was evaluated in Santander, Colombia, a region still presenting active transmission. Serum samples from 638 individuals were submitted to an enzyme immunoassay test (EIA), using total lysate of a local Trypanosoma cruzi strain and 52.5% were positive (335/638). A subset of this group (94 positive individuals and 90 seronegatives) was randomly selected for further serological confirmation. Three additional tests were used--indirect immunofluorescence (IIF) and 2 distinct enzyme-linked immunosorbent assays using total lysate of the Y strain (EIA BM) and a mixture of 2 recombinant antigens (EIA RA). Seventy-nine patients were seropositive in all tests (84.0%-79/94). The number of positive sera with the IIF, EIA RA and EIA BM was 84/94 (89.4%), 80/94 (85.1%) and 79/94 (84.0%), respectively. In 15 out of the 94 EIA seropositive patients (16.0%), 10 individuals were negative in all 3 tests (10.6%-10/94). One was negative in the EIA BM and positive in the other two tests (1.1%-1/94) and 4 patients were positive, solely, in the IIF assay (4.3%-4/94). Relative to the 90 EIA negative individuals, 89 were confirmed in all other tests (98.9%-89/90). One individual, although seronegative in the IIF, was positive in both confirmatory EIA tests (1.1%-1/90). In addition, 120 blood specimens were submitted to PCR amplification. This group consisted of 79 confirmed seropositive cases, 16 individuals with discordant serological results and 25 validated seronegative individuals. The PCR was able to detect the presence of parasite DNA in 67 out of the 79 seropositive patients (84.8%), in 8 individuals with discordant serology (50.0%) and in only one seronegative individual (4.0%). The results pointed to the necessity for performing more than one serological test, preferentially with antigens from autochthonous strains, to achieve a reliable diagnosis of Chagas disease in Colombia.

Architecture-independent approximation of functions.

We show that minimizing the expected error of a feedforward network over a distribution of weights results in an approximation that tends to be independent of network size as the number of hidden units grows. This minimization can be easily performed, and the complexity of the resulting function implemented by the network is regulated by the variance of the weight distribution. For a fixed variance, there is a number of hidden units above which either the implemented function does not change or the change is slight and tends to zero as the size of the network grows. In sum, the control of the complexity depends on only the variance, not the architecture, provided it is large enough.

Cleptohaematophagy of the Triatomine bug Belminus herreri.

The Triatomine bug Belminus herreri, previously known only from Panama, is reported for the first time from Colombia. Three adult B. herreri were collected from a chicken coop and a viable egg was found on a Bactris palm at Carmen municipality in humid forest zone at 680 m altitude. From 44 eggs produced, five progeny were reared to adulthood. During early instars they were unable to take bloodmeals directly from vertebrate hosts, but they fed successfully by cleptohaematophagy on blood from replete Rhodnius prolixus.

Self-calibration of a space robot.

We present a neural-network method to recalibrate automatically a commercial robot after undergoing wear or damage, which works on top of the nominal inverse kinematics embedded in its controller. Our starting point has been the work of Ritter et al. (1989, 1992) on the use of extended self-organizing maps to learn the whole inverse kinematics mapping from scratch. Besides adapting their approach to learning only the deviations from the nominal kinematics, we have introduced several modifications to improve the cooperation between neurons. These modifications not only speed up learning by two orders of magnitude, but also produce some desirable side effects, like parameter stability. After extensive experimentation through simulation, the recalibration system has been installed in the REIS robot included in the space-station mock-up at Daimler-Benz Aerospace. Tests performed in this set-up have been constrained by the need to preserve robot integrity, but the results have been concordant with those predicted through simulation.

On-line learning with minimal degradation in feedforward networks.

Dealing with nonstationary processes requires quick adaptation while at the same time avoiding catastrophic forgetting. A neural learning technique that satisfies these requirements, without sacrificing the benefits of distributed representations, is presented. It relies on a formalization of the problem as the minimization of the error over the previously learned input-output patterns, subject to the constraint of perfect encoding of the new pattern. Then this constrained optimization problem is transformed into an unconstrained one with hidden-unit activations as variables. This new formulation leads to an algorithm for solving the problem, which we call learning with minimal degradation (LMD). Some experimental comparisons of the performance of LMD with backpropagation are provided which, besides showing the advantages of using LMD, reveal the dependence of forgetting on the learning rate in backpropagation. We also explain why overtraining affects forgetting and fault tolerance, which are seen as related problems.

[Amebiasis. Has its clinical expression changed?]. / Amibiasis. Ha variado su expresión clínica?

In Mexico, like in other countries, there is an special interest for amebiasis because it represents a Public health problem; there are about 5 million people that in some time of their lives had tissue invasion by this parasite. 1-2% of mexicanas have intestinal amebiasis and probably there are 850,000 to 1,700,000 carriers of entamoeba cysts. 6% of the general population have circulating antiameba antibodies. In 1988 we studied the amebic hepatic abscess seen in the hospitals of the Instituto Mexicano del Seguro Social in the Valley of Mexico. During that year there were 396 patients with such illness (0.19% of hospital admissions) with a 1.01% mortality. Comparing this data with reports of 1969 there was a reduction in the number of patients and deaths. Also amebiasis has decreased in autopsy studies. However, we have not found recent variations in the clinical behavior of amebiasis. Advances in diagnostic methods and more liberal use of metronidazole have reduced the number of severely ill patients.