Blend design tools for Medium Combustion Plants (MCP) firing biomass wastes

A feasible alternative for agricultural or forestry waste management is the operation of a distributed network of sustainable Medium Combustion Plants (MCPs). However, one of the main factors that hinder its development is the propensity to operational problems derived from corrosion, slagging and fouling characteristics of both bottom and fly ashes. Therefore, a cost-effective approach for these multi-product MCP could be based on predictive tools for an optimal formulation of a fuel blend. This work focuses on the assessment of the ability of these methods to provide guidance for preventing ash-related operational problems and to provide fuel-blending rules. The more widespread tools pertain to two types: compositional classification based on chemical analysis of laboratory ashes, and thermodynamic prediction of the most likely species and phases. Both criterion numbers and compositional maps are ranking methods based on the chemical analysis at a given ashing temperature. Thermodynamic equilibrium modeling is not constrained by any difference in the physical conditions of the MCP compared to those in the laboratory. Both kind of prediction tools have been validated in an MCP firing olive tree pruning residues as well as its typical blends in order to mimic a plausible pattern of fuels along a full year operating campaign. An intensive experimental campaign encompasses plant monitoring and off-line analysis of the ashes along the process line. Interpretation of compositional plots has revealed to be potentially sensitive to ashing temperature. Here are presented examples showing how this variable could lead to either insignificant differences or to a substantial disparity in the a priori fuel diagnosis. Some inconsistencies have been observed between the predictions based on criterion numbers, even for the same fuel and for ranking rules specifically formulated for biomasses. Moreover, it does not match consistently with the information obtained from phase diagrams. Therefore, their use should be limited to the case of a well-established selection of a fuel index for a well-defined fuel provided empirical evidence of an enough good description of the ash behavior, which is not the most frequent case. Thermodynamic equilibrium calculations allow a more precise prediction of the main species in the condensed phase, without the constraint of the ashing temperature. Elemental closure of main ash-forming elements with the chemical analysis of the process ashes presents small differences, and their proximity localization on the phase diagrams denote similar prediction between predicted and process ashes.

Key points and time intervals for early diagnosis in symptomatic oral cancer: a systematic review

The aim of this study was to identify key points and time intervals in the patient pathway to the diagnosis of oral cancer, from the detection of a bodily change to the start of treatment. A systematic search of three databases was performed by two researchers independently. Articles reporting original data on patients with symptomatic primary oral or oropharyngeal squamous cell carcinoma that was pathologically confirmed were included. These articles had to include an outcome variable of 'diagnostic delay', 'time interval', or 'waiting time to diagnosis', or report time intervals from first symptom to treatment. Furthermore, the outcome variable had to have a clearly defined start point and end point, with the time measurement presented as a continuous or categorical variable. A total of 1175 reports were identified; 28 articles on oral cancer studies and 13 on oral and oropharyngeal cancer studies were finally included. These papers showed poor quality in terms of questionnaire validation, acknowledgement of biases influencing time-point measurements, and strategies for verification of patient self-reported data. They also showed great heterogeneity. The review findings allowed the definition of key points and time intervals within the Aarhus framework that may better suit the features of the diagnostic process of this neoplasm, particularly when assessing the impact of waiting time to diagnosis.

International visibility of domestic scientific literature

An indicator to quantify the international diffusion of domestic literature is proposed. It is based on the proportion of articles from a comprehensive domestic database covered by international specialised databases, and is applied to the fields of Physics and Chemistry. The trend to publish abroad in both fields is also introduced. These two indicators are studied for different Spanish sectors: university, research council and industry.

The importance of intraoperative transesophageal echocardiography in the surgical decision in cardiac surgery

OBJECTIVE

To determine the importance of intraoperative transesophageal echocardiography (IOTEE) in the surgical decision in patients undergoing cardiac surgery.

PATIENTS AND METHOD

Prospective observational study of patients undergoing cardiac surgery from January 2009 to May 2012, which was monitored with IOTEE by the anesthesiologist in charge. The data collected were: 1) type of surgery; 2) preoperative echocardiographic diagnosis (baseline ECHO); 3) echocardiographic diagnosis before entering cardiopulmonary bypass (CPB) (pre-CPB IOTEE); 4) any differences between the baseline ECHO and the pre-CPB IOTEE (new pre-CPB finding) and whether these differences modified the planned surgery, and 5) echocardiographic diagnosis after disconnection of CPB (unexpected post-CPB finding) and whether these post-CPB echocardiographic findings led to reinstating it. The software program SPSS(®) was used for data analysis.

RESULTS

The total number of patients studied was 1,273. Monitoring with IOTEE showed "new pre-CPB" findings in 98 patients (7.7%), and 43.8% of these led to a change in the scheduled surgery. Of these findings, the most frequent were abnormalities of the mitral valve that had not been diagnosed, and which led to a replacement or repair that had not been scheduled. The incidence of "unexpected post-CPB findings" was 6.2% (79 patients), and 46.8% of those required reinstating the CPB and modifying the surgery performed. The failed valve repairs and dysfunctional valve prostheses were the main causes that led to re-entry into CPB. In the remaining 42 patients, with "unexpected post-CPB findings", there were no changes in the surgical procedure as the echocardiographic findings were not considered to be significant enough to re-establish CPB and revise or change the surgical procedure.

CONCLUSION

Intraoperative monitoring with IOTEE by the anesthesiologist during surgery provides important information before and after the CPB that resulted in modifying surgical management.

Rehabilitation efficiency and destination on discharge after stroke

BACKGROUND

Predicting functional recovery of patients is key for setting the objectives of the rehabilitation programme and making decisions on their destination on discharge. Many variables have an impact on disability and quality of life after stroke, including patient age, comorbidity, severity of neurological deficit, state of mind and social risk. Accordingly, it is also essential from a care perspective to optimise the functional recovery and efficiency of rehabilitation programmes, exploring their relationship with these variables.

AIM

To analyze the efficiency of post-stroke rehabilitation, identifying factors that most strongly influence functional recovery and destination on discharge.

DESIGN

Multicentre prospective cohort study

SETTING/POPULATION

All patients admitted to the Rehabilitation Units of the two hospitals after stroke over eight months

METHODS

Collected data on sociodemographic characteristics, social risk (Gijón Scale), comorbidity (Charlson Index), neurological severity (National Institute of Health Stroke Scale), daily living functioning scale (Barthel Index), length of hospital stay and destination on discharge.

RESULTS

We included 241 patients, with a mean stay of 35±22 days, 81.5% returning home on discharge. On admission 45.2% were totally dependent, and this figure fell to 12.8% on discharge, the mean Barthel Index score increasing by 32.5 points. Neurological severity, hemiparetic severity, impairment of deep sensation and trunk control on admission were the mayor variables influence on rehabilitation efficiency (P<0.001). Destination on discharge was most closely associated with civil status, social risk and Barthel Index score (P<0.001). The likelihood of transferring to residential care is 3- and 2.71-fold higher among patients with total dependence and high comorbidity scores, respectively.

CONCLUSION

Many variables influence on outcomes of stroke inpatient rehabilitation.

CLINICAL REHABILITATION IMPACT

Comprehensive assessments are required to predict patient recovery, efficiency and plan for discharge.

[Ureterectomy in the treatment of urothelial carcinoma of the distal ureter]

INTRODUCTION

Segmental ureterectomy with preservation of the kidney is a treatment option for the low grade urothelial carcinoma (LG-UC) in distal ureter that is not a candidate for endoscopic resection. Laparoscopic distal ureterectomy (LDU) with ureteral reimplantation is common in benign conditions (stenosis, iatrogenic lesion, endometriosis). However, it has been hardly described in malignant ureteral condition. The literature is reviewed in this regards and the surgical technique described.

MATERIAL AND METHODS

The experience regarding two cases of LDU due to low grade urothelial carcinoma in distal ureter is presented. In both, previous bladder transurethral resection (RTU) was performed. The urinary cytology was negative and the imaging studies identified urinary obstruction and distal ureter filling defect. One of the patients had a background of T1G3 bladder cancer and suffered renal failure. In both, the ureter was ligated early. Segmental ureterectomy was performed using a combined endoscopic and laparoscopic procedure with ureteral desinsertion in one case. In the other, it was exclusively laparoscopic. Both were done with 4 trocars. Ureteral reimplantation was conducted with continuous hermetic suture and without tension. In one case with background of high grade bladder tumor, pelvic lymphadenectomy was also performed.

RESULTS

Operating time was 180 and 240 min, respectively, with estimated bleeding of 100 and 250 ml. Hospitalization time was 6 and 4 days. The only post-operatory complication was paralytic ileum (Clavien I) in the first case. With a 20 and 12 month follow-up, there is no evidence of recurrence or dilatation. In the patient with renal failure, creatinine clearance improved.

CONCLUSIONS

The LDU with ureteral reimplantation is a complex technique. However, it represents a feasible and effective alternative for the treatment of LG-UC in distal ureter, as long as the oncological and reconstructive principles are respected.

Effect of whole linseed and rumen-protected conjugated linoleic acid enriched diets on feedlot performance, carcass characteristics, and adipose tissue development in young Holstein bulls

Forty-eight young Holstein bulls (slaughtered at 458.6±9.79 kg body weight) were used to evaluate the effect of whole linseed and conjugated linoleic acid (CLA) supplementation on animal performance, adipose tissue development, and carcass characteristics. The animals were fed with one of four isoenergetic and isoproteic diets: control (0% linseed, 0% CLA), linseed (10% linseed, 0% CLA), CLA (0% linseed, 2% CLA), and linseed plus CLA (10% linseed, 2% CLA). Animal performance and carcass characteristics were unaffected by diet composition. Adding linseed or CLA to the concentrate diet did not result in significant differences in adipocyte size and number or lipogenic enzyme activity. However, while the frequency distribution of subcutaneous adipocyte diameters followed a normal distribution, the frequency distribution of intramuscular adipocyte diameters was not normal in any dietary group (skewness coefficients: 0.8, 1.2, 0.9, 0.8 for control, linseed, CLA, and linseed plus CLA, respectively; P<0.05), indicative of adipocyte proliferation in the intramuscular adipose tissue.

[Anxiety and depression in carers of dependent patients]

OBJECTIVE

To determine the prevalence of depression and anxiety in main carers of dependent patients as defined by the Dependent Care Law 39/2006.

MATERIAL AND METHODS

We selected 294 main carers of dependent patients as defined by Law 39/2006, and performed a descriptive, cross-sectional and multi-centre study. They were recruited during the first semester of 2009 in 8 urban centres and 2 rural ones in the Communities of Andalusia and Murcia. We measured levels of anxiety and depression using the Hamilton scale, the social support by means of the Duke-UNK scale, sociodemographic, medical variables and associated with the support to the dependent person. The Chi-squared (chi), WiLcoxon and Student t tests were used to describe the data. Multivariate analysis was performed on the most significant data.

RESULTS

A total of 254 carers showed anxiety (86%) (95% CI: 82.47-90.31%) and depression 191 (65%) (95% CI: 59.51-70.41%). The presence of anxiety was statistically significant (P = .043) when associated to: being an unpaid carer, low social support, previous diagnosis of anxiety and depression, taking of psychiatric drugs, and diagnosis of depression using the Hamilton depression scale. The depression presence of depression is associated with: being an unpaid carer, family relationship, previous diagnosis of anxiety and depression, taking of psychiatric drugs, and with an anxiety diagnosis according to the Hamilton scale. No statistically significant differences were detected in the association between Levels of dependency and the appearance of depression and/or anxiety.

CONCLUSIONS

The prevalence of depression and anxiety in the carers of dependent patients is significantly greater than in the general population. The greater the social support the lower the prevalence of these disorders.

Is early diagnosis of oral cancer a feasible objective? Who is to blame for diagnostic delay?

Worldwide, oral cancer has one of the lowest survival rates and poor prognosis remains unaffected despite recent therapeutic advances. Reducing diagnostic delay to achieve earlier detection is a cornerstone to improve survival. Thus, intervention strategies to minimize diagnostic delays resulting from patient factors and to identify groups at risk in different geographical areas seem to be necessary. The identification of a 'scheduling delay' in oral cancer justifies the introduction of additional educational interventions aimed at the whole health care team at dental and medical practices. The access to and the kind of healthcare system in a particular country are also relevant in this context, particularly the referral system. The design of a simple, clear, fail-safe, fast-track referral scheme for those suspected with cancer may diminish greatly the length of the delay. Moreover, there is a need for future investigations, which are methodologically adequate, that consider cultural and geographical aspects and use patient survival as the final outcome, that are able to recognize the agents/factors responsible for diagnostic delay by patients as well as healthcare providers and those attributable to the healthcare systems.

Low-dose beta-lactam plus amikacin in febrile neutropenia: cefepime vs. piperacillin/tazobactam, a randomized trial

Patients with fever and granulocytopenia are at risk of developing severe infection. We performed a prospective, randomized trial to evaluate the efficacy of low-dose cefepime plus amikacin (C-A) compared to low-dose piperacillin/tazobactam plus amikacin (PT-A). Patients received cefepime (2 g/12 h) plus amikacin (15 mg/kg/day) or piperacillin/tazobactam (4 g/500 mg/8 h) plus amikacin. A total of 317 episodes of febrile granulocytopenia in 190 patients were studied (152 in the C-A group, 165 in the PT-A group). A microbiologically documented infection was present in 53 (35%) episodes in the C-A group and 41 (25%) episodes in the PT-A group (p = ns); a clinically documented infection was observed in 39 (26%) and 47 (28%) episodes, respectively. Toxicity was observed in 6 (4%) episodes in the C-A group and in 5 (3%) episodes in the PT-A group. The antibiotic success rate (no change or addition of antibiotics) was recorded in 89 (59%) and 105 (64%) cases, respectively (p = ns). Mortality related to infection was similar in each arm (3.9% vs. 3.6%). Combination therapy of low-dose beta-lactam with an aminoglycoside achieves very good response rates and low rates of toxicity. It might be an attractive option in an environment of increasing resistance among gram-negative bacteria.

The pre-pore from Bacillus thuringiensis Cry1Ab toxin is necessary to induce insect death in Manduca sexta

The insecticidal Cry toxins from Bacillus thuringiensis bacteria are pore-forming toxins that lyse midgut epithelial cells in insects. We have previously proposed that they form pre-pore oligomeric intermediates before membrane insertion. For formation of these oligomers coiled-coil structures are important, and helix alpha-3 from Cry toxins could form coiled-coils. Our data shows that different mutations in helix alpha-3 are affected in pore formation and toxicity. Mutants affected in toxicity bind Bt-R(1) receptor with a similar K(D) as the wild type toxin but do not form oligomers nor induce pore formation in planar lipid bilayers, indicating that the pre-pore oligomer is an obligate intermediate in the intoxication of Cry1Ab toxin and that interaction of monomeric Cry1Ab with Bt-R(1) is not enough to kill susceptible larvae.

Different levodopa actions on the extracellular dopamine pools in the rat striatum

Levodopa has been the mainstay treatment for Parkinson's disease for several decades, but the precise mechanism for its therapeutic action is still not well understood. To date, little distinction has been made between the effects of levodopa on the different brain DA pools. We studied the levodopa action on two extracellular DA pools: one was analyzed by microdialysis (often considered as indicative of volume transmission) and the other by in vivo amperometry during nigrostriatal cell stimulation (more indicative of neurotransmission). Levodopa administration induced a moderate (increased 200%) and tardy (began at 60 min) increase in the DA-pool measured by microdialysis, an effect that increased (increased 500%) and accelerated (began at 10 min) after DA-cell degeneration. Levodopa action on the DA-pool measured by amperometry was very fast (10 min) and prominent (increased 600%) in normal rats. The DA-denervated striatum showed a fast exhaustion during cell stimulation, which prevented further study of the levodopa effect on the DA amperometry-pool under this condition. This study suggests a different kinetic for levodopa action on the volume transmitter and neurotransmitter DA-pool, showing marked changes in levodopa action in the denervated striatum.

Effect of composted sewage sludge application to soil on sweet pepper crop (Capsicum annuum var. annuum) grown under two exploitation regimes

The aim of this study is to monitor the effect of the application of three increasing amounts of composted sewage sludge (3, 6 and 9 kg compost m(-2)) on the physico-chemical properties of a horticultural calcareous soil where sweet pepper plants (Capsicum annuum var. annuum) cv. California were grown. A comparative study of two different exploitation regimes was carried out; the first was an open-air field-grown plot and the second plot was kept under controlled conditions in a greenhouse. Changes in physical and chemical properties measured in soil and sweet pepper crop were recorded during crop growth in order to measure the evolution of these properties as a consequence of increasing compost applications. Organic matter, total nitrogen Kjeldahl and available phosphorus contents increased in soil after composted sewage sludge applications. The 9 kg compost m(-2) application promoted the appearance of deleterious effects on the properties of soil, such as salt accumulation, a significant increase in the electrical conductivity and an input of heavy metals (Pb>Cr>Cd). The 6 kg compost m(-2) application provided a supply of nutrients necessary to grow peppers plants under both exploitation regimes. Pepper fruit biomass production under greenhouse was almost 60% higher compared to that of the open-air plot. Lower contents of Ca and increased levels of Cu in fruit under greenhouse growing conditions compared to those of open-air grown peppers seemed to promote the occurrence of blossom-end rot, affecting more than 10% of the harvested fruits.

Effect of irrigation on the survival of total coliforms in three semiarid soils after amendment with sewage sludge

Sewage sludges are increasingly used in soil amendment programmes, although not without risk since they contain, among other potential hazards, high concentrations of total coliform bacteria. In this paper we have studied the effect of irrigation on the survival of total coliforms in three semiarid degraded soils with different agricultural practices. Fresh sewage sludge was added at 50 g kg(-1) soil, and incubated in both the presence and absence of irrigation. The absence of irrigation led to a sharp decrease in the number of total coliforms in all soils, with the bacteria disappearing in 40 days. Irrigation produced a substantial initial increase in the number of coliforms in the three soils, although after 80 days there was none growing in any of the soils. The results showed that there were significant differences in the survival of coliform bacteria due to the presence or absence of irrigation.

Role of receptor interaction in the mode of action of insecticidal Cry and Cyt toxins produced by Bacillus thuringiensis

Cry toxins from Bacillus thuringiensis are used for insect control. Their primary action is to lyse midgut epithelial cells. In this review we will summarize recent findings on the Cry toxin-receptor interaction and the role of receptor recognition in their mode of action. Cry toxins interact sequentially with multiple receptors. In lepidopteran insects, Cry1A monomeric toxins interact with the first receptor and this interaction triggers oligomerization of the toxins. The oligomer then interacts with second receptor inducing insertion into membrane microdomains and larval death. In the case of mosquitocidal toxins, Cry and Cyt toxins play a part. These toxins have a synergistic effect and Cyt1Aa overcomes Cry toxin resistance. Recently, it was proposed that Cyt1Aa synergizes or suppresses resistance to Cry toxins by functioning as a membrane-bound receptor for Cry toxin.

Internacionalización de la producción científica de España en Radiología y Neuroimagen (1996-2003)

The situation of Research in radiology in Spain is analysed by examining the number of publications by Spanish authors in main stream international journals. The scientific production of Spanish researchers in journals included in the Science Citation Index (SCI) under the headings "Radiology, Nuclear Medicine, and Medical Imaging" and "Neuroimaging" during the years 1996-2003. During this period the scientific production in these fields comprised 1,562 documents (3.5% of the total production for Spanish clinical medicine); scientific production in these fields increased by 40% in this period in comparison to 24% for all clinical medicine. The bulk of the production was concentrated in the autonomous communities of Catalonia (35%), Madrid (28%), and Valencia (10%). The autonomous communities of Navarra and Cantabria had a high relative production after the results were adjusted for population. The healthcare sector is the most active, with the Hospital de la Santa Creu i Sant Pau, the Hospital Clinic de Barcelona, and the Hospital Vall d'Hebron being outstanding in that they not only lead the country in the number of publications but also publish more in journals with high impact factors. Among centers other than hospitals, the Center for Research in Energy, the Environment, and Technologies (CIEMAT) and the Medical School of the Universidad Complutense de Madrid are the most important. A high degree of collaboration is evident: 68% of the documents were produced by more than one institution, foreign centers were involved in 20%, and the documents were signed by an average of six authors. Conclusions. In summary, the data show that Spanish radiological research is becomin increasingly international, although this process is still in the initial stage, with the percentage of documents published in the most prestigious journals for this specialty being lower than in other disciplines. The relative activity and production of Spain is slightly below the average of the European Union, but the country shows a rising trend for both production and impact.

Relationship between oxidative stress parameters and atherosclerotic signs in the carotid artery of stable renal transplant patients

Reactive oxygen species (ROS) may participate in atheroma plaque formation, which may be noninvasively diagnosed by Doppler ultrasound of carotid artery. We sought to determine the relationship between the presence of carotid artery lesions and oxidative parameters to identify factors that may influence these lesions in renal transplant patients. Fifty renal transplanted patients with stable renal function and without diabetes mellitus were studied for more than 1 year posttransplantation. Echo Doppler examination of the carotid artery was performed to assess the intimal media thickness (IMT), atheroma plaques, calcification, and stenosis. Data were collected on oxidative parameters: malondialdehyde (MDA), glutathione peroxidase (GPx), catalase, superoxide dismutase (SOD), glutathione reductase (GR), and lipid profile. The serum GPx level among patients without atheroma plaques, calcification, or stenosis was higher than in those with ultrasound signs. The LDL cholesterol fraction was lower in patients with no ultrasound signs of atherosclerotic lesions; total cholesterol values showed the same behavior. In conclusion, transplanted patients with atheromatous plaques, calcification, and carotid stenosis have a greater degree of hypercholesterolemia and lower antioxidant activity (lower GPx). Recipient age was the principal risk factor for the presence of increased IMT, atheroma plaque, calcification, and/or stenosis of carotid artery in renal transplant patients.

Co phytoavailability for tomato in amended calcareous soils

A plot study was conducted to assess changes in Co phytoavailability for a tomato cultivar grown on an agricultural soil (a Calcic Petrocalcid) amended with sewage sludge, under controlled conditions in South-eastern Spain. The experiment consisted of three main treatment blocks: (A) without organic fertilisation, (B) with addition of 60 tha(-1) and (C) 120 tha(-1) of sewage sludge. For each block (A, B, and C), four levels of Co (0, 50, 100 and 200 mgkg(-1)) were added, as CoCl2. Diethylenetriaminepentaacetic acid, DTPA (0.005 M plus triethanolamine), ammonium acetate (1 N at pH 7), and water extractable fractions of the soils were analysed for all the plots. The time dependent Co accumulation in different parts (roots, stems, leaves, and fruits) of the tomato plants was studied. Soil Co seemed to be mainly in non-available forms, according to the low concentrations found in the water and ammonium acetate extracts, compared to DTPA. The gradient of Co accumulation in tomato plants was root > leaf > stem + branches > fruit, with a concentration in the edible parts ranging between 4 and 25 mg kg(-1). The organic amendment enhanced the plant extraction of Co, this effect being more significant with time. Plant extraction efficiency decreased with increasing Co concentration in the soils. Co in fruit showed the best correlation with all the Co extraction pools in the soil.

[Graft viability of patients with renal transplantation from non heart beating donors]

INTRODUCTION

Renal transplantation (RT) is currently the treatment of choice in end-stage renal disease. The Gregorio Marañón hospital performed 65 RT, 97.01 pmp, this year.

OBJECTIVE

To study the characteristics which RT patients from non-heart beating donors have in the immediate post-transplantation renogram. To know the evolution of the renal function, by renogram.

METHODS

Ten patients with NHBD graft out of 65 patients with RT were studied in the year 2003.

RESULTS

The study is made up of 10 patients with RT from NHBD, with an average timing of warm ischemia of 35 min and average timing of cool ischemia 21 h. In the post-transplantation renal function study, 9 of then showed hemodilution and one an acute tubular necrosis (ATN) pattern. In most of the cases, the study was performed the day after the RT except for one that was performed on the 4th day (1.7 +/- 1 days). Renal perfusion was conserved in every case. The renal graft maintained this type of record until post-RT day 7 (6.67 +/- 0.57 days) and evolved towards ATN after day 10 (11.65 +/- 1.5 days) and normal range on day 55 +/- 51.1 post-transplantation. All patients supported the graft, with acceptable renal function, except one of then who was treated with transplantectomy due to a renal venous thrombosis.

CONCLUSION

The renal function study showed "hemodilution" in the first post-transplantation in 90 % of the RT from NHBD. Evolution went from ATN to normality. The NHBD are adequate for transplantation, significantly shortening the waiting time for RN.

Oligomerization triggers binding of a Bacillus thuringiensis Cry1Ab pore-forming toxin to aminopeptidase N receptor leading to insertion into membrane microdomains

Bacillus thuringiensis Cry1A toxins, in contrast to other pore-forming toxins, bind two putative receptor molecules, aminopeptidase N (APN) and cadherin-like proteins. Here we show that Cry1Ab toxin binding to these two receptors depends on the toxins' oligomeric structure. Toxin monomeric structure binds to Bt-R1, a cadherin-like protein, that induces proteolytic processing and oligomerization of the toxin (Gomez, I., Sanchez, J., Miranda, R., Bravo A., Soberon, M., FEBS Lett. (2002) 513, 242-246), while the oligomeric structure binds APN, which drives the toxin into the detergent-resistant membrane (DRM) microdomains causing pore formation. Cleavage of APN by phospholipase C prevented the location of Cry1Ab oligomer and Bt-R1 in the DRM microdomains and also attenuates toxin insertion into membranes despite the presence of Bt-R1. Immunoprecipitation experiments demonstrated that initial Cry1Ab toxin binding to Bt-R1 is followed by binding to APN. Also, immunoprecipitation of Cry1Ab toxin-binding proteins using pure oligomeric or monomeric structures showed that APN was more efficiently detected in samples immunoprecipitated with the oligomeric structure, while Bt-R1 was preferentially detected in samples immunoprecipitated with the monomeric Cry1Ab. These data agrees with the 200-fold higher apparent affinity of the oligomer than that of the monomer to an APN enriched protein extract. Our data suggest that the two receptors interact sequentially with different structural species of the toxin leading to its efficient membrane insertion.

Conscious compensations for thought insertion

Thought insertion and other experiences of alien control have been explained as a source monitoring deficit, that results from a disconnection between a cognitive system for willed actions and a different system that monitors them. The case we present is a schizophrenic patient that in order to consciously avoid feeling his thoughts as not belonging to himself performs them as a motor act of speech. We suggest an interpretation for this conscious compensation following C. Frith's neuropsychological model of schizophrenia.

Multiple environmental signals determine the transcriptional activation of the mycoparasitism related gene prb1 in Trichoderma atroviride

Trichoderma atroviride parasitizes a large variety of phytopathogenic fungi. This characteristic has allowed its use as a biological control agent. The production of hydrolytic enzymes appears to be a key element in the parasitic process. Among the enzymes released by Trichoderma, the proteinase Prb1 plays a major role. We show here that the corresponding gene ( prb1) is subject to nitrogen catabolite repression. Accordingly, induction of prb1 transcription by Rhizoctonia solani cell walls and by osmotic stress requires release from a repressed condition, which is determined by nitrogen availability. Furthermore, the transcription pattern of the prb1 gene was not affected when an inhibitor of p38-Hog1, a regulator of the response to osmotic shock, was used. In contrast, a MEK1/2 (MAPK/ERK) inhibitor blocked prb1 transcription in response to nitrogen limitation, indicating that the pathway employed in the nitrogen response involves proteins similar to p42-p44. Fusion of the prb1 promoter to the gfp reporter gene allowed the detection of a novel regulatory element, providing an initial insight into the nature of the sites that control prb1 expression.

Laparoscopic diagnosis of acute lower abdominal pain in women of reproductive age

OBJECTIVES

To compare the accuracy of laparoscopy performed within 24 h of admission and the conventional method based on clinical observation in the etiological diagnosis of non-specific acute lower abdominal pain (NSLAP) in women of reproductive age.

METHODS

A total of 110 patients who met the selection criteria and were seen from November 1997 to June 2000 at the Instituto Materno Infantil, a referral hospital for maternal and perinatal care in Bogotá, were randomly divided into two groups. The effectiveness of each method was evaluated according to number of diagnoses reached, length of in-patient stay before diagnosis, complications, and diagnostic accuracy when compared with a standard given by microbiological and histopathological findings as well as clinical course.

RESULTS

The early laparoscopy group did not experience more accurate diagnoses (85% vs. 79%, P=0.61) or a greater number of complications (11% vs. 9%, P=0.48), although the patients' stay was shorter (1.3 vs. 2.3 days, P=0.008) than the stay of the conventional-diagnosis group. Sensitivity analysis showed more accurate judgements with laparoscopy in four of the five NSLAP causes, but only in two of the cases did this greater accuracy have clinical significance.

CONCLUSIONS

Early laparoscopy did not show a clear benefit in women with NSLAP.

Prevalence of Salmonella and Campylobacter in retail chicken meat in Spain

From February to November 1999, 198 samples of chicken meat for sale in retail outlets and supermarkets in nine provinces of Castilla and León (Spain) were analysed for the prevalence of Salmonella and Campylobacter. Salmonella was isolated from 71 (35.83%) of the samples analysed. The predominant serovars were S. enteritidis (47.88%), S. hadar (25.35%) and serotype 4,12:b:-(II) (19.71%). Other serovars such as S. mbandaka, S. derby, S. virchow and S. paratyphi B were isolated in much lower levels. Thermophilic campylobacters were isolated in 49.50% of the samples studied.

Reliable and easy screening technique for salt tolerance of citrus rootstocks under controlled environments

Three salt tolerance experiments using 5 common citrus rootstocks were carried out to find a reliable and easy screening technique for salt tolerance in breeding programs. The experiments were: (1) in vitro seed culture where salt tolerance was mainly evaluated as germination percentage, (2) hydroponic culture of 2-month-old seedlings where salt tolerance was mainly evaluated as survival percentage, and (3) hydroponic culture of satsuma-rootstock combinations where salt tolerance was evaluated by leaf and fruit characters. Treatments were: 4 mm K2CO3 and 0-100 mm NaCl in Expt 1; 3.5 mm K2CO3 and 0-50 mm NaCl, with and without K2CO3, in Expt�2; and 25 mm NaCl in Expt 3. Volkamer lemon was the most salt-sensitive genotype during seed germination (Expt�1), whereas Troyer citrange was the most sensitive when used as rootstock of satsuma (Expt 3). For seedling survival (Expt 2), the trifoliate orange variety Flying dragon showed the highest survival percentage, and chloride content of satsuma leaves and fruit juice were high on this rootstock under salinity (Expt 3). Alkalinity (pH = 8.5) greatly affected seedling survival of Cleopatra mandarin and Volkamer lemon (Expt 2), probably due to major disturbances in seedling nutrition. Analysis of trait values for the rootstocks in the different saline treatments in both the in vitro germination and the seedling survival experiments revealed some significant changes compared with control conditions. Most of these changes were not consistent between genotypes, except for chloride concentration in both shoot ([Cl]s) and root ([Cl]r). The ordering of genotypes for salt tolerance found in the literature, which corresponds to the ordering as chloride excluders in our satsuma Expt 3, agrees with the inverse ordering of genotypes regarding the increment of both [Cl]s and the ratio [Cl]s/[Cl]r from control to low salinity, but does not agree with salt tolerance measured as a percentage of germination or seedling survival. The increments of both [Cl]s and the ratio [Cl]s/[Cl]r from control to low salinity are suggested as criteria for early selection of salt-tolerant citrus rootstocks. Three salt tolerance mechanisms have been observed: chloride exclusion, water saving, and accumulation of soluble solids. They all seem to be presented by Cleopatra mandarin when used as rootstock, supporting its utilisation as donor of salt tolerance in breeding programs of citrus rootstocks.

Mapping the epitope in cadherin-like receptors involved in Bacillus thuringiensis Cry1A toxin interaction using phage display

In susceptible lepidopteran insects, aminopeptidase N and cadherin-like proteins are the putative receptors for Bacillus thuringiensis (Bt) toxins. Using phage display, we identified a key epitope that is involved in toxin-receptor interaction. Three different scFv molecules that bind Cry1Ab toxin were obtained, and these scFv proteins have different amino acid sequences in the complementary determinant region 3 (CDR3). Binding analysis of these scFv molecules to different members of the Cry1A toxin family and to Escherichia coli clones expressing different Cry1A toxin domains showed that the three selected scFv molecules recognized only domain II. Heterologous binding competition of Cry1Ab toxin to midgut membrane vesicles from susceptible Manduca sexta larvae using the selected scFv molecules showed that scFv73 competed with Cry1Ab binding to the receptor. The calculated binding affinities (K(d)) of scFv73 to Cry1Aa, Cry1Ab, and Cry1Ac toxins are in the range of 20-51 nm. Sequence analysis showed this scFv73 molecule has a CDR3 significantly homologous to a region present in the cadherin-like protein from M. sexta (Bt-R(1)), Bombyx mori (Bt-R(175)), and Lymantria dispar. We demonstrated that peptides of 8 amino acids corresponding to the CDR3 from scFv73 or to the corresponding regions of Bt-R(1) or Bt-R(175) are also able to compete with the binding of Cry1Ab and Cry1Aa toxins to the Bt-R(1) or Bt-R(175) receptors. Finally, we showed that synthetic peptides homologous to Bt-R(1) and scFv73 CDR3 and the scFv73 antibody decreased the in vivo toxicity of Cry1Ab to M. sexta larvae. These results show that we have identified the amino acid region of Bt-R(1) and Bt-R(175) involved in Cry1A toxin interaction.

PCR detection of Helicobacter pylori in string-absorbed gastric juice

Molecular methods for detection of Helicobacter pylori infection have been shown to be highly sensitive in gastric biopsies and cultures. The objective of this work was to compare PCR detection of H. pylori DNA in string-absorbed gastric juice and in gastric biopsies. The study was performed in 47 dyspeptic adult patients undergoing endoscopy, and infection was detected by amplification of a segment of H. pylori ureA gene. Of the 29 patients positive in biopsy analysis, 23 (79%) were also positive in the gastric string. PCR analysis of gastric strings is a sensitive and safe procedure to detect H. pylori when endoscopy is not indicated, and may be of great clinical and epidemiological usefulness in determining effectiveness of eradication therapies, typing virulence genes and detecting antibiotic resistance mutations.

Comparison of PCR and common clinical tests for the diagnosis of H. pylori in dyspeptic patients

Helicobacter pylori has been recognized as a major gastric pathogen. The objective of this study was to assess the diagnostic value of common clinical tests to detect H. pylori infection, by comparison with PCR. Serum and gastric biopsy specimens from 106 dyspeptic patients were examined. Serology was performed with Pyloriset Dry test, and biopsies were examined histologically, for rapid urease activity and PCR amplification of an ureA gene segment of H. pylori. PCR primers were specific for H. pylori and required at least 1.47 pg of H. pylori DNA, corresponding to about 800 bacterial cells. According to serology, histology, rapid urease, and PCR, positive results were respectively found in 56%, 86%, 64%, and 85% of dyspeptic patients, primarily with gastritis. Relative to PCR, the sensitivity (and specificity) was 55% (38%) for serology, 86% (13%) for histology, 70% (69%) for urease. When combining histology and urease, Bayesian analysis of data indicated no advantage of using combined methods over rapid urease test alone. Histology should not any longer be considered a gold standard test for Helicobacter pylori. Urea breath test still seems the first option for non invasive diagnostic. If an invasive diagnostic is justified, highly specific and sensitive molecular methods should be used to examine specimens.

Reclamation of a burned forest soil with municipal waste compost: macronutrient dynamic and improved vegetation cover recovery

The reclamation of burned soils in Mediterranean environments is of paramount importance in order to increase the levels of soil protection and minimise erosion and soil loss. The changes produced in the content of total organic carbon (TOC), N (Kjeldahl) and available P, K, Ca and Mg by the addition of different doses of a municipal solid waste compost to a burned soil were evaluated during one year. The effect of organic amendment on the improvement in the vegetation cover after one year was also evaluated. The organic amendment, particularly at a high dose, increased the TOC and N-Kjeldahl content of the soil in a closely related way. The levels of available K in soil were also enhanced by the organic amendment. Although the effects on all three parameters tended to decrease with time, their values in the amended soils were higher than in the control soil, which clearly indicates the improvement in the chemical quality of the soil brought about by the organic amendment. The available P content did not seem to be influenced by organic treatment, while available Mg levels were higher than in the control during the first 4 months following organic amendment. The application of compost to the burned soil improved its fertility and favoured rapid vegetal recovery, thus minimising the risk of soil erosion.

Evidence for intermolecular interaction as a necessary step for pore-formation activity and toxicity of Bacillus thuringiensis Cry1Ab toxin

Based on the observation of large conductance states formed by Bacillus thuringiensis Cry toxins in synthetic planar lipid bilayers and the estimation of a pore size of 10-20 A, it has been proposed that the pore could be formed by an oligomer containing four to six Cry toxin monomers. However, there is a lack of information regarding the insertion of Cry toxins into the membrane and oligomer formation. Here we provide direct evidence showing that the intermolecular interaction between Cry1Ab toxin monomers is a necessary step for pore formation and toxicity. Two Cry1Ab mutant proteins affected in different steps of their mode of action (F371A in receptor binding and H168F in pore formation) were affected in toxicity against Manduca sexta larvae. Binding analysis showed that F371A protein bound more efficiently to M. sexta brush border membrane vesicles when mixed with H168F in a one to one ratio. These mutant proteins also recovered pore-formation activity, measured with a fluorescent dye with isolated brush border membrane vesicles, and toxicity against M. sexta larvae when mixed, showing that monomers affected in different steps of their mode of action can form functional hetero-oligomers.

Antigenicity of chimeric synthetic peptides based on HTLV-1 antigens and the impact of epitope orientation

The present study evaluated four chimeric synthetic peptides incorporating immunodominant sequences from HTLV-1 virus. Monomeric peptides M1, M2, and M3 represent sequences from core (p19) and envelope (gp46) of the virus. The peptide M1 is a p19 (105-124) sequence, the peptide M2 is a gp46 (190-207) sequence, and the peptide M3 is a gp 46 sequence with substitution of proline at position 192 by serine. Those peptides were arranged in such a way that permits one to obtain different combinations of chimeric peptides (M1-M2, M2-M1, M1-M3, and M3-M1). Two glycine residues were used as arm spacers for separating the two sequences. The antigenicity of these peptides was evaluated in an ultramicroenzyme-linked immunosorbent assay (UMELISA) using sera of human T cell leukemia virus type I (HTLV-I)-infected individuals (n = 24), while specificity was evaluated with anti-HTLV-II-positive samples (n = 11) and healthy blood donors (n = 25). The results were compared to plates coated with monomeric peptides M1, M2, and M3. The chimeric peptide orientation (M1-M2) and the proline at position 192 of the gp46 peptide showed higher sensitivity.

Chimeric synthetic peptide as antigen for immunodiagnosis of HIV-1 infection

One chimeric peptide incorporating antigenic sequences from the gp41 transmembrane region (peptide H-18) and the gp120 envelope region (peptide H-15) corresponding to amino acids (587-617) on gp41 and (495-516) on gp120 of human immunodeficiency virus (HIV 1) was synthesized. Both sequences were separated by two glycine residues. This peptide was evaluated as antigen in an ultramicro-enzyme-linked immunosorbent assay (UMELISA) with samples derived from HIV-1 (n = 30) with different titers of antibodies and healthy blood donors (n = 30). The results were compared to plates coated with monomeric peptides and to plates coated with two monomeric peptides together. Results demonstrated that monomeric peptides gp41 (H-18) and gp120 (H-15) were good as antigens with samples that present antibodies to these regions. The chimeric peptide was the most antigenic. Those results may be related to the peptide structure, adsorption to the solid surface, and epitope accessibility to the antibodies. This chimeric peptide would be very useful for HIV-1 diagnostics.

[Study of patients admitted to a telemetry unit]

The current situation of the telemetry unit of Vigil de Quiñones Hospital was studied. Telemetry indications, results, and problems observed since the unit was inaugurated were studied to determine the usefulness of telemetric heart rate monitoring and centralized surveillance in an intensive care unit (ICU) in detecting severe arrhythmias, controlling antiarrhythmic treatment, and evaluating why and to what extent telemetry is clinically useful. In our center, telemetry is used to monitor patients with well-established needs. In most cases, arrhythmias are monitored, most frequently premature ventricular complexes, sinus bradycardia and supraventricular tachycardia. Telemetry was useful in arrhythmia treatment and the follow-up of patients with temporary or permanent pacemakers. In a significant percentage of patients (8.62%), telemetry was the key to their ICU admission and, possibly, their survival. There were generally few problems with signal transmission.