Agrobacterium rhizogenes-mediated transformation of grain (Amaranthus hypochondriacus) and leafy (A. hybridus) amaranths.

KEY MESSAGE: Transgenic A. hypochondriacus and A. hybridus roots were generated. Further, a distinct plant regeneration program via somatic embryos produced from hairy roots was established. Work was implemented to develop an optimized protocol for root genetic transformation of the three grain amaranth species and A. hybridus, their presumed ancestor. Transformation efficiency was species-specific, being higher in A. hypochondriacus and followed by A. hybridus. Amaranthus cruentus and A. caudatus remained recalcitrant. A reliable and efficient Agrobacteruim rhizogenes-mediated transformation of these species was established using cotyledon explants infected with the previously untested BVG strain. Optimal OD600 bacterial cell densities were 0.4 and 0.8 for A. hypochondriacus and A. hybridus, respectively. Hairy roots of both amaranth species were validated by the amplification of appropriate marker genes and, when pertinent, by monitoring green fluorescent protein emission or ß-glucuronidase activity. Embryogenic calli were generated from A. hypochondriacus rhizoclones. Subsequent somatic embryo maturation and germination required the activation of cytokinin signaling, osmotic stress, red light, and calcium incorporation. A crucial step to ensure the differentiation of germinating somatic embryos into plantlets was their individualization and subcultivation in 5/5 media containing 5% sucrose, 5 g/L gelrite, and 0.2 mg/L 2-isopentenyladenine (2iP) previously acidified to pH 4.0 with phosphoric acid, followed by their transfer to 5/5 + 2iP media supplemented with 100 mg/L CaCl2. These steps were strictly red light dependent. This process represents a viable protocol for plant regeneration via somatic embryo germination from grain amaranth transgenic hairy roots. Its capacity to overcome the recalcitrance to genetic transformation characteristic of grain amaranth has the potential to significantly advance the knowledge of several unresolved biological aspects of grain amaranths.

Validation of an instrument to assess health care quality (FACIT-TS-PS) in cancer patients.

INTRODUCTION: Cancer patient satisfaction with the healthcare team is of great relevance for assessing the quality of the care provided by the health system. In Mexico, no valid and reliable tool is available to assess this construct. OBJECTIVE: To validate the Functional Assessment of Chronic Illness Therapy-Treatment Satisfaction-Patient Satisfaction (FACIT-TS-PS) instrument, version 4, in cancer patients. METHOD: Cross-sectional design, non-probability convenience sampling. The sample consisted of 200 cancer-diagnosed patients, with mean age of 45.86 ± 15.01 years. Exploratory and confirmatory factor analyses were conducted. RESULTS: The exploratory factor analysis identified four factors, with a Cronbach alpha of 0.945, and an explained variance of 68.15 %. The confirmatory factor analysis indicated that the proposed theoretical model adjusts to the data with an error close to zero and, in addition, it is balanced and carefully measures overall patient satisfaction with the treatment. CONCLUSION: FACIT-TS-PS was shown to be a valid and reliable instrument for use in clinical care and research in Mexican cancer patients. Its use is recommended in the evaluation of oncology multidisciplinary healthcare teams in Mexico.

INTRODUCCIÓN: La satisfacción del paciente oncológico con el equipo de salud es de relevancia para evaluar la calidad de la atención del sistema de salud. En México no se dispone de una herramienta válida y confiable para evaluar este constructo. OBJETIVO: Validar el Instrumento de Evaluación de Funcionalidad en el Tratamiento para Enfermedades Crónicas-Satisfacción con el Tratamiento-Satisfacción del Paciente (FACIT-TS-PS) versión 4, en pacientes mexicanos con cáncer. MÉTODO: Diseño transversal, muestreo no probabilístico, por disponibilidad. La muestra consistió en 200 pacientes diagnosticados con cáncer, con edad promedio de 45.86 ± 15.01 años. Se realizó un análisis factorial exploratorio y confirmatorio. RESULTADOS: Se identificaron cuatro factores con un alfa de Cronbach de 0.945 y una varianza explicada de 68.15 %. El análisis factorial confirmatorio indicó que el modelo teórico propuesto se ajusta a los datos con error próximo a cero y que, además, es equilibrado y mide cuidadosamente la satisfacción global del paciente con el tratamiento. CONCLUSIÓN: FACIT-TS-PS mostró ser un instrumento válido y confiable para su uso en la atención clínica e investigación dirigida a pacientes mexicanos con cáncer. Se recomienda su utilización en la evaluación de equipos de salud multidisciplinarios en oncología en México.

Development of an Efficient Protocol to Obtain Transgenic Coffee, Coffea arabica L., Expressing the Cry10Aa Toxin of Bacillus thuringiensis.

This report presents an efficient protocol of the stable genetic transformation of coffee plants expressing the Cry10Aa protein of Bacillus thuringiensis. Embryogenic cell lines with a high potential of propagation, somatic embryo maturation, and germination were used. Gene expression analysis of cytokinin signaling, homedomains, auxin responsive factor, and the master regulators of somatic embryogenesis genes involved in somatic embryo maturation were evaluated. Plasmid pMDC85 containing the cry10Aa gene was introduced into a Typica cultivar of C. arabica L. by biobalistic transformation. Transformation efficiency of 16.7% was achieved, according to the number of embryogenic aggregates and transgenic lines developed. Stable transformation was proven by hygromycin-resistant embryogenic lines, green fluorescent protein (GFP) expression, quantitative analyses of Cry10Aa by mass spectrometry, Western blot, ELISA, and Southern blot analyses. Cry10Aa showed variable expression levels in somatic embryos and the leaf tissue of transgenic plants, ranging from 76% to 90% of coverage of the protein by mass spectrometry and from 3.25 to 13.88 µg/g fresh tissue, with ELISA. qPCR-based 2-ΔΔCt trials revealed high transcription levels of cry10Aa in somatic embryos and leaf tissue. This is the first report about the stable transformation and expression of the Cry10Aa protein in coffee plants with the potential for controlling the coffee berry borer.

Metamorphosis of the Basidiomycota Ustilago maydis: transformation of yeast-like cells into basidiocarps.

Ustilago maydis (DC) Cda., a phytopathogenic Basidiomycota, is the causal agent of corn smut. During its life cycle U. maydis alternates between a yeast-like, haploid nonpathogenic stage, and a filamentous, dikaryotic pathogenic form that invades the plant and induces tumor formation. As all the members of the Subphylum Ustilaginomycotina, U. maydis is unable to form basidiocarps, instead it produces teliospores within the tumors that germinate forming a septate basidium (phragmobasidium). We have now established conditions allowing a completely different developmental program of U. maydis when grown on solid medium containing auxins in dual cultures with maize embryogenic calli. Under these conditions U. maydis forms large hemi-spheroidal structures with all the morphological and structural characteristics of gastroid-type basidiocarps. These basidiocarps are made of three distinct hyphal layers, the most internal of which (hymenium) contains non-septate basidia (holobasidia) from which four basidiospores develop. In basidiocarps meiosis and genetic recombination occur, and meiotic products (basidiospores) segregate in a Mendelian fashion. These results are evidence of sexual cycle completion of an Ustilaginomycotina in vitro, and the demonstration that, besides its quasi-obligate biotrophic pathogenic mode of life, U. maydis possesses the genetic program to form basidiocarps as occurs in saprophytic Basidiomycota species.

BRAF Testing in Melanoma and Colorectal Cancer in Latin America: Challenges and Opportunities.

The incidence of colorectal cancer in Argentina and Brazil has reached levels comparable to those in higher-income countries. Similarly, the incidence of melanoma in Latin America has increased during the past decades. BRAFmutation is seen frequently in melanomas and colorectal cancer. Discovering the expression of this specific biomarker in both cancers has unleashed the potential for targeted molecular therapies.In patients with BRAF-mutated melanoma, adopting a combined targeted treatment approach has shown a dramatic increase in overall survival. However, several barriers impede the development of early BRAF testing in Latin America, jeopardizing the potential for personalized therapies and care. To address this, the Americas Health Foundation convened a virtual meeting of Latin American oncologists to address the barriers to BRAF testing in melanoma and colorectal cancer. During a three-day conference, expert oncologists used literature reviews and personal experience to detail the barriers to early BRAF testing in their region. They proposed actionable steps to overcome the barriers identified, which included deficiencies in knowledge, treatment options, equitable distribution, timely results, and local data on BRAF mutations. Oncologists proposed several actions to overcome barriers, including raising public and healthcare awareness about the importance of BRAF testing, expanding treatment options in clinics across the region, developing centers in underserved areas, and increasing affordable treatment options for patients who test positive for BRAF mutations.

Correction: BRAF Testing in Melanoma and Colorectal Cancer in Latin America: Challenges and Opportunities.

[This corrects the article DOI: 10.7759/cureus.31972.].

Osmotic stress-induced somatic embryo maturation of coffee Coffea arabica L., shoot and root apical meristems development and robustness.

Somatic embryogenesis (SE) is the most important plant biotechnology process for plant regeneration, propagation, genetic transformation and genome editing of coffee, Coffea arabica L. Somatic embryo (SEs) conversion to plantlets is the principal bottleneck for basic and applied use of this process. In this study we focus on the maturation of SEs of C. arabica var. Typica. SEs conversion to plantlet up to 95.9% was achieved under osmotic stress, using 9 g/L gelrite, as compared with only 39.34% in non-osmotic stress. Mature SEs induced in osmotic stress developed shoot and root apical meristems, while untreated SEs were unable to do it. C. arabica regenerated plants from osmotic stress were robust, with higher leaf and root area and internode length. To understand a possible regulatory mechanism, gene expression of key genes of C. arabica, homologous to sequences in the Arabidopsis thaliana genome, were analyzed. A set of two component system and cytokinin signaling-related coding genes (AHK1, AHK3, AHP4 and ARR1) which interact with WUSCHEL and WOX5 homedomains and morphogenic genes, BABY-BOOM, LEC1, FUS3 and AGL15, underwent significant changes during maturation of SEs of C. arabica var. Typica. This protocol is currently being applied in genetic transformation with high rate of success.

Infection, transfection, and co-transfection of baculoviruses by microprojectile bombardment of larvae.

The use of baculoviruses as expression vectors for heterologous proteins has been practically limited to the use of the Autographa californica multiple nucleopolyhedrovirus (AcMNPV). In this work, infection, transfection and co-transfection events with the baculoviruses AcMNPV and Trichoplusia ni granulovirus (TnGV) were accomplished by bombardment of T. ni first-instar larvae with microprojectiles coated with virions, viral DNA, and viral DNA and a transfer vector, respectively. A series of shooting conditions were tested until positive results were obtained. The use of 1.6 microm gold particles at 900 psi shooting pressure, 400 Torr vacuum, 7 cm distance to target, on sets of 20 first-instar larvae held in a 16 mm diameter container, proved to be the best shooting conditions. Typical infection symptoms were shown by larvae when shot with viruses or viral DNA from AcMNPV or TnGV. Co-transfected recombinant AcMNPV and TnGV were identified by the formation of occlusion bodies and GFP, respectively, in bombarded larvae. This technique opens a wide range of possibilities, not only to use an extensive number of baculoviruses as expression vectors for heterologous proteins, but also be used to infect, transfect or co-transfect a wide variety of viruses into animal cells.

Identification of the slow wave component of the electroenterogram from Laplacian abdominal surface recordings in humans.

The electroenterogram (EEnG) is a surface recording of the myoelectrical activity of the smooth muscle layer of the small intestine. It is made up of two signals: a low-frequency component, known as the slow wave (SW), and high-frequency signals, known as spike bursts (SB). Most methods of studying bowel motility are invasive due to the difficult anatomic access of the intestinal tract. Abdominal surface EEnG recordings could be a noninvasive solution for monitoring human intestinal motility. However, surface EEnG recordings in humans present certain problems, such as the low amplitude of the signals and the influence of physiological interference such as the electrocardiogram (ECG) and respiration. In this study, a discrete estimation of the abdominal surface Laplacian potential was obtained using Hjorth's method. The objective was to analyze the enhancement given by Laplacian EEnG estimation compared to bipolar recordings. Eight recording sessions were carried out on eight healthy human volunteers in a state of fasting. First, the ECG interference content present in the bipolar signals and in the Laplacian estimation were quantified and compared. Secondly, to identify the SW component of the EEnG, respiration interference was removed by using an adaptive filter, and spectral estimation techniques were applied. The following parameters were obtained: the dominant frequency (DF) of the signals, stability of the rhythm (RS) of the DF detected and the percentage of DFs within the typical frequency range for the SW (TFSW). Results show the better ability of the Laplacian estimation to attenuate ECG interference, as compared to bipolar recordings. As regards the identification of the SW component of the EEnG, after removing respiration interference, the mean value of the DF in all abdominal surface recording channels and in their Laplacian estimation ranged from 0.12 to 0.14 Hz (7.3 to 8.4 cycles min(-1) (cpm)). Furthermore in 80% of the cases, the detected DFs were inside the typical human SW frequency range, and the ratio of frequency change in the surface bipolar and Laplacian estimation signals, in 90% of the cases, was within the frequency change accepted for human SW. Significant statistical differences were also found between the DF of all surface signals (bipolar and Laplacian estimation) and the DF of respiration. In conclusion, it was demonstrated that the discrete Laplacian potential estimation attenuated the physiological interference present in bipolar surface recordings, especially ECG. Furthermore, a slow frequency component, whose frequency, rhythm stability and amplitude fitted with the SW patterns in humans, was identified in bipolar and Laplacian estimation signals. This could be a useful non-invasive tool for monitoring intestinal activity by abdominal surface recordings.

Free osseous and soft tissue surgical margins as prognostic factors in mandibular osteosarcoma.

Osteosarcoma is an infrequent, locally aggressive neoplasm in the head and neck region. To date, surgery is the mainstay of treatment. However, patients with mandibular osteosarcomas usually have a locally advanced disease at diagnosis and therefore represent a therapeutic challenge because surgical margins are difficult to obtain due to aesthetic and functional concerns. To evaluate possible prognostic factors implicated in recurrence, persistence or relapse in osteosarcoma of the mandible, with special reference to the soft tissue and bone surgical margins. A series of 20 patients with mandibular osteosarcomas treated at the Instituto Nacional de Cancerología (México) from 1985 to 1999 are reviewed. There were 14 female and 6 male patients. Twelve cases were treated with surgery alone, 3 patients with surgery and adjuvant radiotherapy, 1 had neoadjuvant chemotherapy followed by surgery, 1 had neoadjuvant chemotherapy, surgery and postoperative radiotherapy, 1 with surgery and adjuvant chemotherapy, 1 with surgery followed by adjuvant chemotherapy and radiotherapy and one patient rejected treatment. Between 1985 and 1992 these neoplasms were treated by means of total mandibulectomy, independently of tumor size, but between 1993 and 1999 the policy was to practice smaller resections but long enough to obtain macroscopic surgical free margins. In the first period the relationship between mandibular size resection and tumor size was 1.9, meanwhile in the second period the relation was 1.5. There was not significant difference between both periods in terms of tumor size (6.0 cm vs. 6.02 cm at the time of surgery) nor in local control and survival. Soft tissue involvement as reported by histological study was strongly associated with recurrence (p = 0.0024). Overall 5-year survival was 20%. A policy of total mandibulectomy is not associated with a better local control or survival. Extent of resection must be tailored with tumor size. Extent of margins in soft tissue is the limiting factor for local control.

Adaptive filtering of ECG interference on surface EEnGs based on signal averaging.

An external electroenterogram (EEnG) is the recording of the small bowel myoelectrical signal using contact electrodes placed on the abdominal surface. It is a weak signal affected by possible movements and by the interferences of respiration and, principally, of the cardiac signal. In this paper an adaptive filtering technique was proposed to identify and subsequently cancel ECG interference on canine surface EEnGs by means of a signal averaging process time-locked with the R-wave. Twelve recording sessions were carried out on six conscious dogs in the fasting state. The adaptive filtering technique used increases the signal-to-interference ratio of the raw surface EEnG from 16.7 +/- 6.5 dB up to 31.9 +/- 4.0 dB. In addition to removing ECG interference, this technique has been proven to respect intestinal SB activity, i.e. the EEnG component associated with bowel contractions, despite the fact that they overlap in the frequency domain. In this way, more robust non-invasive intestinal motility indicators can be obtained with correlation coefficients of 0.68 +/- 0.09 with internal intestinal activity. The method proposed here may also be applied to other biological recordings affected by cardiac interference and could be a very helpful tool for future applications of non-invasive recordings of gastrointestinal signals.

Noninvasive measurement and analysis of intestinal myoelectrical activity using surface electrodes.

Intestinal myoelectrical activity (IMA), which determines bowel mechanical activity, is the result of two components: a low-frequency component [slow wave (SW)] that is always present, and a high-frequency component [spike bursts (SB)] which is associated with bowel contractions. Despite of the diagnostic significance of internal recordings of IMA, clinical application of this technique is limited due to its invasiveness. Thus, surface recording of IMA which is also called electroenterogram (EEnG) could be a solution for noninvasive monitoring of intestinal motility. The aim of our work was to identify slow wave and spike burst activity on surface EEnG in order to quantify bowel motor activity. For this purpose, we conducted simultaneous recordings of IMA in bowel serosa and on abdominal surface of five Beagle dogs in fast state. Surface EEnG was studied in spectral domain and frequency bands for slow wave and spike burst energy were determined. Maximum signal-to-interference ratio (7.5 dB +/- 36%) on SB frequency band was obtained when reducing upper frequency limit of signal analysis. Energy of external EEnG in reduced SB frequency band (2-7.9 Hz) presented a high correlation (0.71 +/- 7%) with internal intensity of contractions. Our results suggest that energy of SB can be quantified on external EEnG which could provide a noninvasive method for monitoring intestinal mechanical activity.

The Phaseolus vulgaris PvTRX1h gene regulates plant hormone biosynthesis in embryogenic callus from common bean.

Common bean is the most important grain legume in the human diet. Bean improvement efforts have been focused on classical breeding techniques because bean is recalcitrant to both somatic embryogenesis and in vitro regeneration. This study was undertaken to better understand the process of somatic embryogenesis in the common bean. We focused on the mechanisms by which somatic embryogenesis in plants is regulated and the interaction of these mechanisms with plant hormones. Specifically, we examined the role of the gene PvTRX1h, an ortholog of a major known histone lysine methyltransferase in plants, in somatic embryo generation. Given the problems with regeneration and transformation, we chose to develop and use regeneration-competent callus that could be successively transformed. Embryogenic calli of common bean were generated and transformed with the PvTRX1hRiA construction to down-regulate, by RNA interference, expression of the PvTRX1h gene. Plant hormone content was measured by mass spectrometry and gene expression was assessed by q-PCR. Detailed histological analysis was performed on selected transgenic embryogenic calli. It was determined that down-regulation of PvTRX1h gene was accompanied by altered concentrations of plant hormones in the calli. PvTRX1h regulated the expression of genes involved in auxin biosynthesis and embryogenic calli in which PvTRX1h was down-regulated were capable of differentiation into somatic embryos. Also, down-regulation of PvTRX1h showed increased transcript abundance of a gene coding for a second histone lysine methyltransferase, PvASHH2h. Accordingly, the PvTRX1h gene is involved in the synthesis of plant hormones in common bean callus. These results shed light on the crosstalk among histone methyltransferases and plant hormone signaling and on gene regulation during somatic embryo generation.

Validación de FACIT-TS-PS en una muestra de pacientes mexicanos con cáncer / Validation of an instrument to assess health care quality (FACIT-TS-PS) in cancer patients

Resumen Introducción: La satisfacción del paciente oncológico con el equipo de salud es de relevancia para evaluar la calidad de la atención del sistema de salud. En México no se dispone de una herramienta válida y confiable para evaluar este constructo. Objetivo: Validar el Instrumento de Evaluación de Funcionalidad en el Tratamiento para Enfermedades Crónicas-Satisfacción con el Tratamiento-Satisfacción del Paciente (FACIT-TS-PS) versión 4, en pacientes mexicanos con cáncer. Método: Diseño transversal, muestreo no probabilístico, por disponibilidad. La muestra consistió en 200 pacientes diagnosticados con cáncer, con edad promedio de 45.86 ± 15.01 años. Se realizó un análisis factorial exploratorio y confirmatorio. Resultados: Se identificaron cuatro factores con un alfa de Cronbach de 0.945 y una varianza explicada de 68.15 %. El análisis factorial confirmatorio indicó que el modelo teórico propuesto se ajusta a los datos con error próximo a cero y que, además, es equilibrado y mide cuidadosamente la satisfacción global del paciente con el tratamiento. Conclusión: FACIT-TS-PS mostró ser un instrumento válido y confiable para su uso en la atención clínica e investigación dirigida a pacientes mexicanos con cáncer. Se recomienda su utilización en la evaluación de equipos de salud multidisciplinarios en oncología en México.

Abstract Introduction: Cancer patient satisfaction with the healthcare team is of great relevance for assessing the quality of the care provided by the health system. In Mexico, no valid and reliable tool is available to assess this construct. Objective: To validate the Functional Assessment of Chronic Illness Therapy-Treatment Satisfaction-Patient Satisfaction (FACIT-TS-PS) instrument, version 4, in cancer patients. Method: Cross-sectional design, non-probability convenience sampling. The sample consisted of 200 cancer-diagnosed patients, with mean age of 45.86 ± 15.01 years. Exploratory and confirmatory factor analyses were conducted. Results: The exploratory factor analysis identified four factors, with a Cronbach alpha of 0.945, and an explained variance of 68.15 %. The confirmatory factor analysis indicated that the proposed theoretical model adjusts to the data with an error close to zero and, in addition, it is balanced and carefully measures overall patient satisfaction with the treatment. Conclusion: FACIT-TS-PS was shown to be a valid and reliable instrument for use in clinical care and research in Mexican cancer patients. Its use is recommended in the evaluation of oncology multidisciplinary healthcare teams in Mexico.

AtTCTP2, an Arabidopsis thaliana homolog of Translationally Controlled Tumor Protein, enhances in vitro plant regeneration.

The Translationally Controlled Tumor Protein (TCTP) is a central regulator of cell proliferation and differentiation in animals, and probably also in plants. Arabidopsis harbors two TCTP genes, AtTCTP1 (At3g16640), which is an important mitotic regulator, and AtTCTP2 (At3g05540), which is considered a pseudogene. Nevertheless, we have obtained evidence suggesting that this gene is functional. Indeed, a T-DNA insertion mutant, SALK_045146, displays a lethal phenotype during early rosette stage. Also, both the AtTCTP2 promoter and structural gene are functional, and heterozygous plants show delayed development. AtTCTP1 cannot compensate for the loss of AtTCTP2, since the accumulation levels of the AtTCTP1 transcript are even higher in heterozygous plants than in wild-type plants. Leaf explants transformed with Agrobacterium rhizogenes harboring AtTCTP2, but not AtTCTP1, led to whole plant regeneration with a high frequency. Insertion of a sequence present in AtTCTP1 but absent in AtTCTP2 demonstrates that it suppresses the capacity for plant regeneration; also, this phenomenon is enhanced by the presence of TCTP (AtTCTP1 or 2) in the nuclei of root cells. This confirms that AtTCTP2 is not a pseudogene and suggests the involvement of certain TCTP isoforms in vegetative reproduction in some plant species.

Pheochromocytoma in MEN 2A syndrome. Study of 54 patients.

BACKGROUND: Pheochromocytoma occurs in nearly 50% of MEN 2A (multiple endocrine neoplasia, type 2A) cases. Many issues related to this tumor are still the subject of debate: the diagnostic management in patients who have had positive genetic study results (RET mutation), variations related to mutation, the best surgical option, and the real relapse rate during long-term follow-up. The aim of this study is to present our experience with this unusual disease, looking for answers to some of these questions. PATIENTS AND METHODS: Of 169 patients belonging to 19 MEN 2A families, 54 (32%) presented with pheochromocytoma. The following variables have been studied: (1) clinical and diagnostic data [age, mutation, clinical features, results of catecholamines and catabolites in a 24-h urine sample, computerized tomography (CT) scan and iodine-131 meta-iodobenzylguanidine (MIBG) scintigraphy results, and the means of diagnostic, clinical, or genetic screening]; (2) surgical treatment; and (3) follow-up and recurrence. The mean follow-up time was 92.5 months (range: 12-120 months). RESULTS: The mean age of the 54 patients was 37.9 years (range: 14-71 years); 33 were women. Most (96.3%) mutations were found in exon 11. The most frequent mutations were Cys634Tyr (in 33 cases [61.1%]) and Cys634Arg (in 14 [25.9%]). The diagnosis of pheocromocytoma was made after the diagnosis of MTC in 26 cases (48.2%), simultaneously in 21 (38.9%), and prior in the 7 remaining cases (12.9%). At the time of diagnosis 28 patients (51.8%) were asymptomatic and 26 (48.2%) had clinical features related to pheochromocytoma. In 6 patients (11.1%), the values of catecholamines and catabolites in urine were normal. In the cases with high values, the most useful isolated determination was that of metanephrines (82%), followed by adrenaline (76%). The CT scan did not provide a correct diagnosis in 6 patients with bilateral lesions, and one patient with a bilateral tumor was not diagnosed by MIBG. The combination of CT scan and MIBG diagnosed 100% of cases. The pheochromocytoma was bilateral in 27 cases, with a total number of 81 pathological glands detected. A laparascopic approach was used in 30 cases and a laparotomy in 24. The mean tumor size was 4.5 cm (range: 1-18 cm). Five patients with unilateral resection relapsed (18.5%), and the mean relapse time was 43.2 months (range: 12-120 months). There was a greater frequency of pheochromocytoma in those subjects who had the Cys634Arg mutation (p < 0.03). In addition, the Cys634Arg mutation is more frequent in bilateral cases. There are no prognostic factors for recurrence. CONCLUSIONS: Pheochromocytoma in MEN 2A is related to the type of mutation, which can be early onset and is frequently asymptomatic. Its diagnosis requires catecholamines determinations as well as a CT scan. Correct diagnosis of bilaterality is established by CT and MIBG. Laparoscopic adrenalectomy is the treatment of choice.

Signal noise ratio of small intestine myoelectrical signal recorded from external surface.

Electroenterogram (EEnG), which is the myoelectrical activity of the small bowel, can be non-invasively recorded from abdominal external surface. However, this bioelectrical signal is weak and noisy compared to internal recording from bowel serous layers, because of bioelectric transmission through abdominal layers. Furthermore, it is contaminated with several interferences from other biological activities as cardiac muscle (ECG), skeletal muscles (EMG), or respiration movements. The goal of present work is to study abdominal recording of EEnG and its signal-to-noise ratio by means of the coherence estimation technique. External and internal recordings were obtained simultaneously in 12 sessions, which went on more than two hours in six beagle dogs. Coherence function, based on periodograms, is estimated in periods of 15 minutes. Thus, SNR is calculated from coherence estimation for each recording session. Results show that SNR reaches a maximum value of 8.8 dB for 0.31 Hz, which corresponds to fundamental frequency of the EEnG slow wave. However, SNR is weak at frequencies upper 2 Hz, which corresponds to rapid action potentials (spike bursts) of the EEnG. In conclusion, slow wave can be clearly identified in abdominal recording; however spike bursts are contaminated by noise, attenuation and biological interferences.

Discrete Laplacian recordings of the electroenterogram from abdominal surface in humans.

The first aim of this study was to obtain the discrete Laplacian of the myoelectric small intestine signal (electroenterogram, EEnG) from bipolar recordings on the abdominal surface in humans. In addition, the objective was to identify the slow wave (SW) component of the EEnG in the estimated Laplacian, as well as to compare this signal with the bipolar surface recordings. It was carried out 8 recording sessions in 6 healthy volunteers. The discrete Laplacian of the surface potential was performed using Hjorth's Laplacian estimation method. In order to identify the SW component of the EEnG, an adaptive filter, which removes breath interference from abdominal surface recordings, was designed. After that, periodograms and their dominant frequency were obtained. The results show that this frequency, in all surface recording channels and in their corresponding Laplacian, ranges from 0.12 to 0.16 Hz (7.3 to 9.8 cycles per minute) inside of the SW frequency range, whereas the frequencies of the respiration ranges from 0.21 to 0.31 Hz (12.9-18.4 cpm). Furthermore abdominal surface Laplacian potential contains averaged SW, information unless any bipolar surface channel do not record properly this signal. Consequently EEnG surface recordings can become a low cost technique to study bowel motility non-invasively.

Estudio longitudinal y transversal de la Sala de Seguridad de hombres del Hospital Vilardebó: segunda parte. Violencia y trastornos relacionados con sustancias / Analysis of the men Security Ward of the Hospital Vilardebo. Violence and substance related disorders

En el presente estudio, que abarca una población de 154 pacientes ingresados entre enero de 1998 y agosto de 1999, es posible arribar a ciertas conclusiones. Por un lado, el importante peso de los trastornos relacionados con sustancias, que abarcan el 61 por ciento de los ingresos. Asimismo, este grupo tiene una alta proporción de delitos violentos (en especial, rapiña y homicidio) y se verifica que la sala 11 concentra la violencia, siendo estos delitos muchos más frecuentes en el servicio comparado con los procesamientos a nivel nacional. Se hace un estudio valorativo de estos datos