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This chapter presents a novel methodology for using feature selection in hand biometric systems, based on genetic algorithms and mutual information. The aim is to provide a standard features dataset which diminishes the number of features to extract and decreases the complexity of the whole identification process. The experimental results show that it is not always necessary to apply sophisticated and complex classifiers to obtain good accuracy rates. This methodology approach manages to discover the most suitable geometric hand features, among all the extracted data, to perform the classification task. Simple classifiers like K-Nearest Neighbour (kNN) or Linear Discriminant Analysis (LDA) in combination with this strategy, getting even better results than other more complicated approaches.

Self-Organizing Maps (SOM) have some problems related to its fixed topology and its lack of representation of hierarchical relations among input data. Growing Hierarchical SOMs (GHSOM) solve these limitations by generating a hierarchical architecture that is automatically determined according to the input data and reflects the inherent hierarchical relations among them. These advantages can be utilized to perform a compression of an image, where the size of the codebook (leaf neurons in the hierarchy) is automatically established. Moreover, this hierarchy provides a different compression at each layer, where the deeper the layer, the lower the compression rate and the higher the quality of the compressed image. Thus, different trade-offs between compression rate and quality are given by the architecture. Also, the size of the codebooks and the depth of the hierarchy can be controlled by two parameters. In this paper, a new approach for image compression based on the GHSOM model is proposed. Experimental results confirm its good performance.

Digital crimes are a part of modern life but evidence of these crimes can be captured in network traffic data logs. Analysing these logs is a difficult process, this is especially true as the format that different attacks can take can vary tremendously and may be unknown at the time of the analysis. The main objective of the field of network forensics consists of gathering evidence of illegal acts from a networking infrastructure. Therefore, software tools, and techniques, that can help with these digital investigations are in great demand. In this paper, an approach to analysing and visualising network traffic data based upon the use of self-organising maps (SOM) is presented. The self-organising map has been widely used in clustering tasks in the literature; it can enable network clusters to be created and visualised in a manner that makes them immediately more intuitive and understandable and can be performed on high-dimensional input data, transforming this into a much lower dimensional space. In order to show the usefulness of this approach, the self-organising map has been applied to traffic data, for use as a tool in network forensics. Moreover, the proposed SOM takes into account the qualitative features that are present in the traffic data, in addition to the quantitative features. The traffic data was was clustered and visualised and the results were then analysed. The results demonstrate that this technique can be used to aid in the comprehension of digital forensics and to facilitate the search for anomalous behaviour in the network environment.

Since the introduction of the growing hierarchical self-organizing map, much work has been done on self-organizing neural models with a dynamic structure. These models allow adjusting the layers of the model to the features of the input dataset. Here we propose a new self-organizing model which is based on a probabilistic mixture of multivariate Gaussian components. The learning rule is derived from the stochastic approximation framework, and a probabilistic criterion is used to control the growth of the model. Moreover, the model is able to adapt to the topology of each layer, so that a hierarchy of dynamic graphs is built. This overcomes the limitations of the self-organizing maps with a fixed topology, and gives rise to a faithful visualization method for high-dimensional data.

Object tracking in video sequences remains as one of the most challenging problems in computer vision. Object occlusion, sudden trajectory changes and other difficulties still wait for comprehensive solutions. Here we propose a feature weighting method which is able to discover the most relevant features for this task, and a competitive learning neural network which takes advantage of such information in order to produce consistent estimates of the trajectories of the objects. The feature weighting is done with the help of a genetic algorithm, and each unit of the neural network remembers its past history so that sudden movements are adequately accounted for. Computational experiments with real and artificial data demonstrate the performance of the proposed system when compared to the standard Kalman filter.

In this paper, a novel methodology for using feature selection in hand biometric systems, based on genetic algorithms and mutual information is presented. A hand segmentation algorithm based on adaptive threshold and active contours is also applied, in order to deal with complex backgrounds and non-homogeneous illumination.

The objectives of this epidemiological, prospective study were to describe the characteristics of cytomegalovirus (CMV) infection in heart transplant (HT) recipients and to identify the variables that may influence the development of CMV viremia and CMV disease in these patients.HT recipients ≥18 years of age (n=199) were included in the study. Variables studied included CMV serostatus, immunosuppressive treatment, and administration of anti-CMV prophylaxis.The mean age of the population was 52 years, and 84% were males. Immunosuppressive regimens were administered as induction therapy to 92.5% of patients; 88.5% of patients received calcineurin inhibitors as maintenance therapy. Anti-CMV treatment was given to 59% of 199 patients as prophylaxis (70%), preemptive therapy (10%), or to treat CMV infection (20%). Overall, 43% of patients had at least 1 positive viremia test. No patient with a high-risk serostatus (donor+/recipient-) receiving prophylaxis developed CMV syndrome, and only 2.5% of 199 patients developed CMV invasive disease. Multivariate analysis showed that having a positive donor CMV serostatus was associated with an increased risk of developing CMV viremia (P0.012), while use of mammalian target of rapamycin (mTOR) inhibitors was associated with a decreased risk (P=0.005).In a population of HT recipients, the CMV infection rate was similar to that seen in previous studies, but the progression to overt CMV disease was very low. Having a CMV-positive donor was identified as an independent risk factor for developing CMV viremia, while the use of mTOR inhibitors was protective against viremia.

An anomaly detection system based on a hierarchical self-organizing neural network is presented. The proposed neural network reduces the amount of parameters that a user should define prior to the training to a single parameter. This allows the network to perform more autonomously while maintaining a good performance, which is less dependent on the user experience about the application domain. The experimental results show the behavior of the anomaly detection system when it is applied to the KDD Cup 1999 data set.

This paper present a video segmentation method which separate pixels corresponding to foreground from those corresponding to background. The proposed background model consists of a competitive neural network based on dipoles, which is used to classify the pixels as background or foreground. Using this kind of neural networks permits an easy hardware implementation to achieve a real time processing with good results. The dipolar representation is designed to deal with the problem of estimating the directionality of data. Experimental results are provided by using the standard PETS dataset and compared with the mixture of Gaussians and background subtraction methods.

A Growing Competitive Neural Network system is presented as a precise method to track moving objects for video-surveillance. The number of neurons in this neural model can be automatically increased or decreased in order to get a one-to-one association between objects currently in the scene and neurons. This association is kept in each frame, what constitutes the foundations of this tracking system. Experiments show that our method is capable to accurately track objects in real-world video sequences.

A novel approach for image segmentation is proposed in this paper. This approach is based on the growing hierarchical self-organizing map (GHSOM), which consists of a hierarchical architecture composed of growing self-organizing maps (SOMs). The SOMs have shown to be successful for the analysis of high-dimensional input data as in data mining applications. The hierarchical architecture of the GHSOM is more flexible than a single SOM in the adaptation process to input data, mirroring inherent hierarchical relations among input data. Image hierarchical segmentation can be achieved by using this neural network model, where the hierarchical structure of segmented regions is captured. In order to evaluate the performance of this segmentation method, an application for hierarchical background modeling in video sequences is provided. Therefore, foreground detection is achieved. Experimental results show that the proposed approach is promising for applications where hierarchical segmentation is required.

This paper presents a hierarchical self-organizing neural network for intrusion detection. The proposed neural model consists of a hierarchical architecture composed of independent growing self-organizing maps (SOMs). The SOMs have shown to be successful for the analysis of high-dimensional input data as in data mining applications such as network security. An intrusion detection system (IDS) monitors the IP packets flowing over the network to capture intrusions or anomalies. One of the techniques used for anomaly detection is building statistical models using metrics derived from observation of the user's actions. The proposed growing hierarchical SOM (GHSOM) address the limitations of the SOM related to their static architecture. Experimental results are provided by applying the well-known KDD Cup 1999 benchmark data set, which contains a great variety of simulated networks attacks. Randomly selected subsets that contain both attacks and normal records from this benchmark are used for training the GHSOM. Before training, a transformation for qualitative features present in the benchmark data set is proposed in order to compute distance among qualitative values. Comparative results with other related works are also provided.

The aim of this paper is to present the use of Growing Competitive Neural Networks as a precise method to track moving objects for video-surveillance. The number of neurons in this neural model can be automatically increased or decreased in order to get a one-to-one association between objects currently in the scene and neurons. This association is kept in each frame, what constitutes the foundations of this tracking system. Experiments show that our method is capable to accurately track objects in real-world video sequences.

This work proposes an unsupervised competitive neural network based on adaptive neighborhoods for video segmentation and object detection. The designed neural network is proposed to form a background model based on subtraction approach. The synaptic weights and the adaptive neighborhood of the neurons serve as a model of the background and are updated to reflect the statistics of the background. The segmentation performance of the proposed neural network is examined and compared to mixture of Gaussian models. The proposed algorithm is parallelized on a pixel level and designed to enable efficient hardware implementation to achieve real-time processing at great frame rates.

The self-organizing map (SOM) have shown to be successful for the analysis of high-dimensional input data as in data mining applications such as network security. However, the static architecture and the lack of representation of hierarchical relations are its main drawbacks. The growing hierarchical SOM (GHSOM) address these limitations of the SOM. The GHSOM is an artificial neural network model with hierarchical architecture composed of independent growing SOMs. One limitation of these neural networks is that they just take into account numerical data, even though symbolic data can be present in many real life problems. In this paper a new GHSOM model with a new metric incorporing both numerical and symbolic data is proposed. This new GHSOM model is proposed for detecting network intrusions. An intrusion detection system (IDS) monitors the IP packets flowing over the network to capture intrusions or anomalies. One of the techniques used for anomaly detection is building statical models using metrics derived from observation of the user's actions. Randomly selected subsets that contains both attacks and normal records from the KDD Cup 1999 benchmark are used for training the proposed GHSOM. Experimental results are provided and compared to other hierarchical neural networks.

The aim of this work is to present a segmentation method to detect moving objects in video scenes, based on the use of a multivalued discrete neural network to improve the results obtained by an underlying segmentation algorithm. Specifically, the multivalued neural model (MREM) is used to detect and correct some of the deficiencies and errors off the well-known mixture of Gaussians algorithm. Experimental results, using video scenes publicly available from the Internet, show an increase of the visual quality of the segmentation, that could improve for subsequent analysis phases, such as object tracking or behavior studies.

The impact of chemotherapy on the extent of breast cancer angiogenesis is unknown. The aim of this study was to investigate the effect of primary chemotherapy on tumor microvessel density and vascular endothelial growth factor (VEGF), and correlate this changes with tumor response, post-chemotherapy changes and other biological variables.In 41 consecutive patients with breast cancer stages II and III, treated with anthracycline-based neoadjuvant chemotherapy, immunohistochemical analysis of microvessel density and VEGF were performed before and after the administration of neoadjuvant chemotherapy.Microvessel density was the same in post-chemotherapy that in pre-chemotherapy samples (p = 0.29). There were no changes in the expression of VEGF (p = 0.23). The expression of VEGF and microvessel density did not show any relationship with the response in the pre-chemotherapy analysis (p = 0.60 and p = 0.30 respectively), nor in the post-chemotherapy analysis (p = 0.50 and p = 0.65 respectively). Changes post-chemotherapy were not associated with VEGF expression (p = 0.53 in the pre-chemotherapy samples and p = 0.43 in the post-chemotherapy samples) nor microvessel density (p = 0.72 in the pre-chemotherapy samples and p = 0.65 in the post-chemotherapy samples).Anthracycline-based neoadjuvant chemotherapy does not cause a reduction of the density of microvessel nor of the expression of VEGF in breast cancer.

During last 50 years chemotherapy has played a very important part in the cancer treatment. However, success or failures of news drugs in one particular cancer its difficult to predict. In vitro chemosensitivity is an attractive method for knowing about responses of a tumor to ChT treatment and assess the best dose in the patient with cancer.To know brain tumors sensitivity against antineoplastic drugs.Five different drugs (carmustin, camptotecin, taxol, hydroxyurea and tamoxifen) were tested on short-term cultures from 7 patients with Glioblastoma multiforme, 15 patients with meningiomas and one patient with meduloblastoma. For testing chemosensitivity we used MTT assay, and we measured optic density by spectophotometry to 450 nm. RESULTS. A total of 49 measurement were done, getting 44 valid dose-result curves. For each drug we used from 10-2 M to 10-12 M gap, and IC50 result was representative of tumor sensitivity to the drug.our data support MTT assays like valid method for measuring in vitro chemosensitivity in brain tumors to news drugs.

Sometimes tuberculosis diagnosis is missed at hospital admission. Delayed diagnosis of active pulmonary tuberculosis among hospitalized patients could to contribute to nosocomial transmission. The objective of this study was to define the occurrence and associated patient risk factors among hospitalized patients with delayed diagnosis of respiratory tuberculosis.A retrospective chart review was undertaken between 1995 and 2002 on all patients with pulmonary tuberculosis. Time intervals between admission, diagnosis and treatment of tuberculosis were determined. Epidemiological and clinical features were evaluated for their effect on these time intervals.Among 149 patients newly diagnosed to have active pulmonary TB, the diagnosis was initially missed in 102 (68% [95% CI, 61 to 75%]) of all hospitalized patients, of whom 66 (65% [95% CI, 56 to 74%]) were smear positive. Treatment was initiated after a week or more in 62 (42% [95% CI, 34% to 50%]) of all patients, of whom 34 (55% [95% CI, 43 to 67%])) were smear positive. Ageor= 60 years (OR 3.17 [95% CI; 1.27 to 7.87]; p = 0.013), presence of chronic lung disease (OR 2.99 [95% CI; 1.21 to 7.38]; p = 0.017), negative sputum AFB smear (OR 4.51 [95% CI; 1.34 to 15.16]; p = 0.015) and absence of hemoptysis or melanoptysis (OR 2.96 [95% CI; 1.18 a 7.41]; p = 0.020), were independently associated with delays.The diagnosis and treatment of hospitalized patients with pulmonary tuberculosis is often delayed because absence of clinic suspicion owing to old age, chronic lung disease or atypical presentations and slow confirmation by culture. Improved clinical acumen, development of rapid diagnostic tests, and the institution of early empiric therapy are desirable objectives to improve the tuberculosis control.

Fundamento y objetivo: en algunos pacientes el diagnóstico de tuberculosis no es sospechado en el momento del ingreso hospitalario, favoreciendo su transmisión nosocomial. El objetivo del estudio era valorar el retraso diagnóstico que se produce en los pacientes ingresados con tuberculosis respiratoria en nuestro hospital y los factores que lo determinan. Pacientes y métodos: estudio retrospectivo de todos los pacientes hospitalizados con tuberculosis pulmonar entre 1995 y 2002. En cada paciente se registraron variables clínico-epidemiológicas y el tiempo desde el ingreso hasta el inicio del aislamiento respiratorio y del tratamiento antituberculoso. Resultados: 149 pacientes fueron diagnosticados de tuberculosis pulmonar durante una hospitalización. El diagnóstico no fue sospechado en las primeras 24 horas del ingreso en 102 pacientes (68% [IC95%, 61 a 75%]), de los cuales 66 (64,7% [IC95%, 56 a 74%]) tenían tinción de esputo positiva. En 62 pacientes (42% [IC95%, 34 a 50%]) se inició tratamiento tuberculostático pasados más de 7 días desde el ingreso, de ellos 34 (55% [IC95%, 43 a 67%]) tenían tinción de esputo positiva. Se asocian independientemente a mayor retraso diagnóstico: edad ≥ 60 años (OR 3,17 [IC95%; 1,27 a 7,87]; p = 0,013), presencia de enfermedad pulmonar crónica (OR 2,99 [IC95%; 1,21 a 7,38]; p = 0,017), tinción de esputo negativa (OR 4,51 [IC95%; 1,34 a 15,16]; p = 0,015) y ausencia de hemoptisis o melanoptisis (OR 2,96 [IC95%; 1,18 a 7,41]; p = 0,020). Conclusiones: El retraso en el diagnóstico y tratamiento de pacientes que ingresan con tuberculosis respiratoria es frecuente, incluso en pacientes con tinción de esputo positiva, por falta de sospecha clínica (sobre todo en pacientes ancianos, con patología pulmonar crónica o con manifestaciones atípicas de la enfermedad). Estos datos ponen de manifiesto la necesidad de mantener un alto índice de sospecha, desarrollar pruebas de diagnóstico rápido e iniciar precozmente un tratamiento empírico para mejorar el control de la enfermedad.

The manufacturing environment is characterized by rapid change, originating new challenges and problems to the production and operation manager in the industry. In response to the need for fast and flexible manufacturing, increasing attention is being given to integration of computing technologies with the manufacturing systems leading to the development of fast and flexible manufacturing systems aided with high performance vision capabilities. This paper presents an inspection and recognition system for manufacturing applications in difficult industrial environments. In such difficult environments, where objects to be recognized can be dirty and illumination conditions cannot be sufficiently controlled, the required accuracy and rigidity of the system are critical features. The purpose of the real-time system is to inspect and recognize air-conditioning objects for avoiding deficiency in the manufactured process and erroneous identifications due to a large variety of size and kinds of objects. The proposed system is composed by five USB cameras (640times480 pixel resolution, 30 Hz frame rates and 8 mm lenses) plug into a conventional computer (Pentium IV 3 GHz). The edged images are features which are relatively robust against illumination changes, so the system can work well in difficult environments mentioned. Experimental results on inspection and recognition of a large variety of air-conditioning objects are provided to show the performance of the system in a difficult environment.

The Advanced Power Electronics Interfaces for Distributed Energy Workshop, sponsored by the California Energy Commission Public Interest Energy Research program and organized by the National Renewable Energy Laboratory, was held Aug. 24, 2006, in Sacramento, Calif. The workshop provided a forum for industry stakeholders to share their knowledge and experience about technologies, manufacturing approaches, markets, and issues in power electronics for a range of distributed energy resources. It focused on the development of advanced power electronic interfaces for distributed energy applications and included discussions of modular power electronics, component manufacturing, and power electronic applications.

Publisher Summary This chapter discusses the research on four relevant topics on Lorentzian geometry. Several Lorentzian results are compared to Riemannian or indefinite (non-Lorentzian) ones, emphasizing on mathematical behaviors, which are specific of Lorentzian geometry. Degenerate tangent planes play an important role in the study of the geometry of Lorentzian manifolds. Harris introduced the notion of null sectional curvature for degenerate tangent planes, which has shown to be fruitful to get some comparison theorems and to characterize Robertson–Walker spacetimes. The chapter discusses Bochner technique on Lorentzian manifolds focusing aims and difficulties.

We sought to evaluate the usefulness of Tc-99m-sestamibi breast scintigraphy in predicting neoadjuvant chemotherapy response in patients with breast cancer.In 50 consecutive patients with breast cancer stages II and III, physical examination, mammography and scintimammography were performed before and after the administration of neoadjuvant chemotherapy. The 3 assessments were compared for predictive value using a pathological response as reference. Values derived from visual assessment of the scintimammography, a quantitative tumor/background index, and isotope clearance were compared to the immunohistochemical expression of P-glycoprotein, vascular endothelial growth factor (VEGF) and microvessel density (CD31) in relation to neoadjuvant chemotherapy response.Macroscopic response was obtained in 10 cases (20%). Sensitivity was 86.5% (95% confidence interval [CI], 70.4-94.9) for the physical examination, 83.3% (95% CI, 68-92.5) for the mammography and 76.5% (95% CI, 58.4-88.6) for the scintimammography. Specificity was 38.5% (95% CI, 15.1-67.7) for the physical examination, 42.9% (95% CI, 11.8-79.8) for the mammography and 8.3% (95% CI, 0.4-40.2) for the scintimammography. There were no statistically significant differences in isotope uptake and clearance with regard to response nor in relation to levels of expression of P-glycoprotein, VEGF and microvessel density.Breast scintigraphy with Tc-99m-sestamibi is not useful in predicting the response to neoadjuvant chemotherapy in breast cancer. Traditional physical examination and mammography are more effective. Isotope uptake and clearance do not predict response and there is not an effective in vivo measurement of chemo-resistance or tumor angiogenesis.

Extragodanal germ cell tumors (EGCT) are not common, especially among women. Although there is no evidence of relationship between this sort of tumor and HIV infection they can appear at the same time in a patient, because in both cases the maximum incidence occurs in patients in the same age group. We present the case of a 27 years old woman, poly-drug user, with a recently diagnosis of HIV infection, who was admitted to clinic because of infection and shortage of breath, and develops during her hospitalization diarrhoea, generalized tonic-clonic seizure and left hemiparesis. Complementary tests showed us diffuse interstitial pulmonary pattern, mediastinal mass with intrathoracic adenopathies, cerebral tumor and diffuse intestinal enlargement. The breath infection got better with a wide-ranging antibiotic treatment, which included cotrimoxazol and levofloxacin, but the brain tumor didńt get better with the antitoxoplasma treatment. The clinical presentation simulated in the beginning a disseminated lymphoma, in a HIV+ patient; nevertheless, after receiving the result of the biopsy of a supraclavicular adenopathy and a b-HCG, an extragodanal germ cell tumor was diagnosed. We haven't found any case of EGCT in young women infected with HIV in our bibliographical review (MEDLINE).

Los tumores de células germinales extragondales (TCGE) son poco frecuentes, sobre todo en mujeres. Aunque no existe evidencia de asociación entre este tipo de tumor y la infección por VIH, pueden coincidir en el mismo paciente debido a que, en ambos, la máxima incidencia se da en el mismo segmento de edad. Presentamos el caso de una mujer de 27 años, politoxicómana, con infección por VIH de reciente diagnóstico, que ingresa por clínica de infección e insuficiencia respiratoria y desarrolla durante su hospitalización, diarrea, crisis tónico-clónica generalizada y hemiparesia izquierda. En las pruebas complementarias practicadas se evidencia patrón intersticial pulmonar difuso, masa mediastínica con adenopatías intratorácicas, lesión ocupante de espacio (LOE) cerebral y engrosamiento intestinal difuso. La infección respiratoria mejoró con tratamiento antibiótico de amplio espectro que incluía cotrimoxazol y levofloxacino, pero la LOE cerebral no mejoró con tratamiento antitoxoplasma. La presentación clínica inicialmente simulaba la de un linfoma diseminado, en una paciente VIH +, sin embargo, tras recibir el resultado de la biopsia de una adenopatía supraclavicular y de b-HCG se realizó el diagnóstico de tumor de células germinales extragonadal. En la revisión bibliográfica realizada (MEDLINE) no hemos encontrado ningún caso de TCGE en mujeres jóvenes con infección por VIH.

Differences in the imaging characteristic of adult medulloblastomas have been reported, including involvement of lateral cerebellar hemispheres with an extra-axial appearance. We present a case report of this rare circumstance: a 40 year old man presented with a 3 weeks history of headache, morning vomiting and left hearing difficulties. Magnetic resonance imaging revealed a left cerebellopontine angle (CPA) tumor, like a well circumscribed homogeneously enhancing mass. Through a left suboccipital craniectomy the tumor was totally removed. It presented as a cerebellopontine angle tumor, like a meningioma, and not as an intra-axial tumor. Histological analysis revealed that the tumor was composed of densely packed with highly proliferative cells that produce a dense intercellular reticulin fiber network. Inmunohistochemical analysis showed positive expression to synaptophysin, specific neuronal enolase and cromogranin. Histological diagnosis was crucial to define it as a desmoplastic medulloblastoma the present case and to perform postoperative adjuvant therapy. Neurosurgeons should be aware of the possibility that a CPA tumor is of intraaxial origin, because this increase the variability on pathological diagnosis.

Objective: To review the available literature on psychoeducation and cognitive-behavioral therapy (CBT) in bipolar disorder (BD) and to give an integral view of these therapies. Method: Studies were identified through Medline searches in English language publications between 1971 and 2003. This was supplemented by a hand search and the inclusion of selected descriptive articles on good clinical practice. Results: A number of studies demonstrate that psychoeducation enhances adherence to treatment, and one finds that it improves outcome in BD. Other studies find that CBT diminishes depressive symptoms and improves quality of life in BD. Occasionally some adverse effects may occur with psychotherapy and, although they are sporadic, should not be overlooked. Conclusion: When combined with pharmacological treatment, psychoeducation helps to improve adherence. Training in the identification of early manic symptoms helps to improve outcomes and decreases the number of manic relapses in BD.

The pathologic gastroesophageal reflux (PGER) can be treated medically or surgically [1–6]. To date, there is not an accepted criterion to divide the patients in each category of treatment. Neither the symptoms, manometry, image studies (baritate or isotopic) nor endoscopy lesions alone have achieved this purpose. The introduction of the ambulatory esophageal pH monitoring for 24 h has permited us a more reliable method for the diagnosis of PGER [7–9].

Immunocytochemistry of glycogen deposition in dog sperm from fresh ejaculates showed that 53.7% of the population had glycogen at the midpiece, whereas 27.3% of the whole population accumulated glycogen only in the post-acrosomal region of the head. A similar distribution was observed when glycogen synthase, the enzyme which controls glycogen deposition, was studied. Incubation of spermatozoa with fructose increases the intracellular glycogen levels in a time- and concentration-dependent manner. Moreover, after incubation with 2 mM fructose for 30 min, 47.3% of the spermatozoa had glycogen located in both the midpiece and post-acrosomal zone, 25.4% of the population showed the polysaccharide only in the midpiece, and 24.7% of the spermatozoa showed a uniform distribution of glycogen all over the cell. Similar results were observed after incubation with 10-mM fructose. The distribution of glycogen synthase followed a similar pattern to that of glycogen. Incubation with glucose also induced a time- and concentration-dependent increase of glycogen content, whereas incubation with 2 mM glucose for 30 min showed that the majority of the population (81.2%) had the glycogen distributed throughout either the midpiece or the midpiece and the post-acrosomal zones together. There were practically no cells with a uniform glycogen distribution. Similar results were obtained after incubation with 10-mM glucose, whereas glycogen synthase suffered a similar glucose-induced distribution change. These results indicate that dog-sperm glycogen metabolism is modulated by changes in the activity of their controlling enzymes and also by changes in the specific location places where glycogen synthesis is produced.

Incubation of dog spermatozoa with 10 mmol l(-1) glucose or fructose rapidly increased the intracellular content of glucose 6-phosphate and fructose 6-phosphate, although the effect of fructose was greater. These effects were correlated with increases in ATP, ribose 5-phosphate and glycogen contents, and in the rates of formation of L-lactate and CO2. In all cases, except for ATP and glycogen, the effect of fructose was greater than that of glucose. The total hexokinase activity of the crude extracts of dog spermatozoa was more sensitive to fructose than to glucose at lower concentrations (0.1-3.0 mmol l(-1)). Both monosaccharides induced a fast and intense increase in the overall tyrosine phosphorylation of dog spermatozoa, although their specific induced-phosphorylation patterns differed slightly. Glut 3 and Glut 5 hexose transporters were the main hexose transporters in dog spermatozoa; however, other possible SGLT family-related hexose transporters were also localized. These data indicate that, at concentrations from 1 mmol l(-1) to 10 mmol l(-1), fructose has a stronger effect than glucose on hexose metabolism of dog spermatozoa. These differences appear to be related to variations in the sensitivity of hexokinase activity. Moreover, the differential hexose metabolism induced by the two sugars had distinct effects on the function of dog spermatozoa, as revealed by the diverse patterns of tyrosine phosphorylation.

Growing hierarchical self-organizing models are characterized by the flexibility of their structure, which can easily accomodate for complex input datasets. However, most proposals use the Euclidean distance as the only error measure. Here we propose a way to introduce Bregman divergences in these models, which is based on stochastic approximation principles, so that more general distortion measures can be employed. A procedure is derived to compare the performance of networks using different divergences. Moreover, a probabilistic interpretation of the model is provided, which enables its use as a Bayesian classifier. Experimental results are presented for classification and data visualization applications, which show the advantages of these divergences with respect to the classical Euclidean distance.

Isolation of Hanseniaspora uvarum, a yeast of the ascomycetes group, whose anamorph corresponds to Kloeckera apiculata, obtained from stool and two ungual specimens from three patients, is reported. This yeast has been found in soil, water, various fruits, bivalve molluscs, crabs, prawns and fruit flies; in Spain, it has been described in the fermentation processes of some wines. In our region, it has also been found in the intestine of mackerel (Scomber scombrus). Its finding in humans constitutes a clinical rarity.

The involvement of bone in non-Hodgkin's lymphoma (NHL) is rare and usually occurs in the late stages of the disease. The involvement of the cranial vault is exceptional and we have found only eleven cases previously reported in the revised literature, none of them in an AIDS patient. We report a case of a 38 years old man, intravenous drug abuser with AIDS diagnosed who presented with coma. Computed tomography scan showed a left frontal intra-parenchymatous haematoma and multiple osteolytic lesions in the whole of the cranial vault, that involved outertable, diploe and innertable. Intra-parenchymatous haematoma was removed and a biopsy of the osteolytic lesions was performed. Histology showed features of a large B-cell NHL. Patient died of infectious pulmonary complications. The incidence of NHL in patients with congenital or acquired immunodeficiencies is increasing and Epstein-Barr virus and other factors have been involved in its pathogenesis. That's the first AIDS patient reported to have a NHL involving the cranial vault. Tumour was limited to the cranial vault without involvement of soft-tissue. An intra-parenchymatous haematoma was associated without an explained cause.

Epstein-Barr virus-associated smooth muscle proliferations have been reported in immunosuppressed patients with acquired immunodeficiency syndrome and after organ transplantation. We report here a case of a histologically benign case arising in a 48-year-old male who had received immunosuppressive therapy 4 years earlier, after cardiac transplantation. In the necropsy performed for unrelated reasons, an incidental left intramyocardial tumor was discovered. The presence of Epstein-Barr virus was confirmed by EBER-1 in situ hybridization and polymerase chain reaction. To the best of our knowledge, this is the first case of an Epstein-Barr virus-associated smooth muscle proliferation arising in the heart after cardiac transplantation and should be added to the potential complications of this kind of procedure.

Although rare, amyloidosis and hemochromatosis are the infiltrative diseases in which the heart is more frequently involved. The most common clinical presentation is heart failure with hemodynamic features of restrictive heart disease in cardiac amyloidosis. The diagnosis is often made because of symptoms of other organ involvement, although sometimes cardiac symptoms may be the initial manifestation. The non-specific clinical presentation and the low prevalence of these cardiomyopathies make the diagnosis difficult if the clinician does not suspect it. Once symptoms develop, the evolution is fast. Usually, the unsatisfactory and ineffective treatment of amyloidosis and hemochromatosis contribute to the poor prognosis. The indication of cardiac transplantation in advanced cases is questionable because of the high recurrence of the illness.

Proof of Proposition 2.3. Let V ∈ X(TM) be given by ĝ(Vv, X) = g(c(X),Kπv) + g(v,∇dπ(X)K), for every X ∈ TvTM . Thus we have ĝ(Vv,Av) = 1, at any v ∈ CK(M), and so Dv = Span{Vv,Av} is a Lorentzian vector subspace of TvTM (recall that ĝ(A,A) = 0 on CKM). One easily checks that X ∈ TvCKM if and only if ĝ(Av, X) = ĝ(Vv, X) = 0. Therefore, (CKM, ĝ) is a Lorentzian manifold. The proof for spacelike fibres remains valid. Finally, [Tv(CKM)p] = {X ∈ TvTM : c(X) = −g(v,∇dπ(X)K) v}, and so π restricted to CKM is a semi-Riemannian submersion.

The present paper reviews the course of the nerves that comprise the pelvic plexus and intervene in the mechanisms of sexual strength and urinary continence. By means of cross-sectional and sagittal incisions in prostates obtained through necropsies the neurovascular bundle, intimately related to the prostatic gland, is studied. Based on the information obtained in the study we raise a series of suggestions all related with the surgical technique of radical retropubic prostatectomy.

The purpose of this paper was to evaluate the results after acute septic arthritis of the knee in children and to discuss the method of treatment. 51 cases records of septic arthritis of the knee in children were studied with an average follow-up of 5 years. The etiology was hematogenous in 42 cases, penetrating wounds in 7 cases and osteomyelitis in 2 cases. Treatment was chiefly joint washing by arthrotomy 36 times, arthroscopy 4 times, with a needle 8 times; 3 synovectomies were necessary. Patients underwent systematic joint immobilization and parenteral antibiotics. The results were excellent in 35 cases, good in 10 cases, fair in 6 cases. Prognosis was good for hemategenous arthritis, but much less so for arthritis secondary to penetrating wounds and osteomyelitis. The essential factor for a good result was an early diagnosis and treatment. Apart from 2 arthrodeses, functional results were good. One of the noteworthy facts of our series was the great number of negative cultures (68 per cent). Treatment is discussed according to literature. Joint washing by arthroscopy has the double advantage of being simple and innoculous, and enables synovial biopsy. Immobilization at first seems necessary but its duration can be shortened to encourage articular cartilage nutrition. Antibiotics must be given parenterally at first, to be continued by oral administration as soon as their efficiency is proven. To evaluate this, CRP seems to be an efficient test.

From 1974 to May 1991, 417 patients with abdominal hydatid cyst disease were surgically treated. Twenty-eight patients had extrahepatic abdominal cyst disease (6.7%). Six patients had only extrahepatic disease where as 22 had associated hepatic and extrahepatic cysts. Most frequent sites were the peritoneum (52.7%), the spleen (22%) and pelvis (11%). Fourteen out of the 14 CT scans performed, detected the extrahepatic cysts. The preferred surgical technique was total closed cystectomy (in hepatic and extrahepatic cysts). Resection of the organ affected (8 splenectomies, 1 nephrectomy, 1 partial vertebral resection, 1 orchiectomy and 1 salpingo-oophorectomy) was also performed. There was no mortality and morbidity was 32.1%: 3 intraabdominal abscesses, 1 intraabdominal haemorrhage, 4 biliary fistulae and 1 partial necrosis of the large bowel. Only 3 patients (neither were treated with mebendazole) were reoperated on for recurrent peritoneal hydatic cyst.