Environmental pollution by heavy metals within the area influenced by the Tungurahua volcano eruption - Ecuador

Volcanic eruptions can have long-lasting negative effects on nearby environments and communities, especially those relying on agriculture. The Tungurahua and Sangay volcanoes in Ecuador's highlands pose a significant risk to the region's agricultural economy and inhabitants. The most recent eruption of the Tungurahua volcano spanned from September 1999 to March 2016. Volcanic ash is known to contain both non-essential and essential elements for plant growth, but excessive amounts of the latter can also be toxic and disrupt physiological processes. Additionally, the use of pesticides and fertilizers introduces additional elements to agricultural soils, which can potentially transfer to edible plants and raise health concerns for consumers. Despite this, little is known about the impact of the Tungurahua volcano's latest eruption on soil deposition of micronutrient and heavy metals and their potential transfer to the food chain. To address this knowledge gap, we conducted a study to explore the impact of the Tungurahua volcano's latest eruption on soil deposition of Cd, Cr, Ni, Pb, As, Fe, Cu, Mn, and Zn, as well as the physicochemical characteristics of cultivated and uncultivated soil samples and vegetables in the cantons most affected by volcanic ash. According to our findings, the physicochemical properties, micronutrient, and heavy metal concentrations of both cultivated and uncultivated soils differ and, in some cases, exceeded the maximum limits established, which could affect the health of the soil as well as of human beings through the trophic chain. This study provides valuable information for monitoring the chemical and physical properties of soil and vegetables in areas affected by the Tungurahua volcanic activity and agriculture, aiding in understanding their impact on the environment, agriculture, and potential health risks associated with locally grown crops in rural Ecuadorian communities.

Approaches to Enhance Sugar Content in Foods: Is the Date Palm Fruit a Natural Alternative to Sweeteners?

The current levels of added sugars in processed foods impact dental health and contribute to a range of chronic non-communicable diseases, such as overweight, obesity, metabolic syndrome, type 2 diabetes, and cardiovascular diseases. This review presents sugars and sweeteners used in food processing, the current possibility to replace added sugars, and highlights the benefits of using dates as a new natural, nutritious and healthy alternative to synthetic and non-nutritive sweeteners. In the context of environmental sustainability, palm groves afford a propitious habitat for a diverse array of animal species and assume a pivotal social role by contributing to the provisioning of sustenance and livelihoods for local communities. The available literature shows the date as an alternative to added sugars due to its composition in macro and micronutrients, especially in bioactive components (fiber, polyphenols and minerals). Therefore, dates are presented as a health promoter and a preventative for certain diseases with the consequent added value. The use of damaged or unmarketable dates, due to its limited shelf life, can reduce losses and improve the sustainability of date palm cultivation. This review shows the potential use dates, date by-products and second quality dates as sugar substitutes in the production of sweet and healthier foods, in line with broader sustainability objectives and circular economy principles.

Diagnostic accuracy of ultrasound signs for detecting adnexal torsion: systematic review and meta-analysis

OBJECTIVE

To evaluate the diagnostic accuracy of different ultrasound signs for diagnosing adnexal torsion, using surgery as the reference standard.

METHODS

This was a systematic review and meta-analysis of studies published between January 1990 and November 2021 evaluating ovarian edema, adnexal mass, ovarian Doppler flow findings, the whirlpool sign and pelvic fluid as ultrasound signs (index tests) for detecting adnexal torsion, using surgical findings as the reference standard. The search for studies was performed in PubMed/MEDLINE, CINAHL, Scopus, The Cochrane Library, ClinicalTrials.gov and Web of Science databases. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was used to evaluate the quality of the studies. Pooled sensitivity, specificity, and positive and negative likelihood ratios were calculated separately, and the post-test probability of adnexal torsion following a positive or negative test was also determined.

RESULTS

The search identified 1267 citations after excluding duplicates. Eighteen studies were ultimately included in the qualitative and quantitative syntheses. Eight studies (809 patients) analyzed the presence of ovarian edema, eight studies (1044 patients) analyzed the presence of an adnexal mass, 14 studies (1742 patients) analyzed ovarian Doppler flow, six studies (545 patients) analyzed the whirlpool sign and seven studies (981 patients) analyzed the presence of pelvic fluid as ultrasound signs of adnexal torsion. Overall, the quality of most studies was considered to be moderate or good. However, there was a high risk of bias in the patient-selection and index-text domains (with the exception of the whirlpool sign) in a significant proportion of studies. Pooled sensitivity, specificity, and positive and negative likelihood ratios of each ultrasound sign were 58%, 86%, 4.0 and 0.49 for ovarian edema, 69%, 46%, 1.3 and 0.67 for adnexal mass, 65%, 91%, 7.6 and 0.38 for the whirlpool sign, 53%, 95%, 11.0 and 0.49 for ovarian Doppler findings and 55%, 69%, 1.7 and 0.66 for pelvic fluid. Heterogeneity was high for all analyses.

CONCLUSIONS

The presence of an adnexal mass or pelvic fluid have poor diagnostic accuracy as ultrasound signs of adnexal torsion, while the presence of ovarian edema, the whirlpool sign and decreased or absent ovarian Doppler flow have good specificity but moderate sensitivity for detecting adnexal torsion. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Valorization of date palm (Phoenix dactylifera L.) pruning biomass by co-composting with urban and agri-food sludge

In the Mediterranean countries, there is an increasing production of date palm wastes (Phoenix dactylifera L.), not only due to the raising production of date palm fruits, but also derived from the maintenance of urban and peri-urban green areas, especially in those affected by red palm weevil (Rhynchophorus ferrugineus). The management of this increasing volume of green wastes usually concludes with a controlled disposal that implies an important loss of resources, in terms of organic matter, nutrients and energy. In addition, the rise of wastewater generation and the incentive of the wastewater treatment processes have derived in an increase of the amount of the sludge produced, which makes difficult its management. This work studies the feasibility of co-composting palm wastes with sludge from the urban and agri-food sectors as alternative treatment to manage these organic waste streams and to obtain added-value compost. For this, four mixtures (P1, P2, P3 and P4) were prepared using as main component palm leave waste (PL) mixed with different types of sludge. In the piles P1, P2 and P3, sewage sludge (SS) was used as co-composting agent, while agri-food sludge (AS) was used in P4. Throughout composting, the thermal profile of the composting piles was assessed, as were physical, chemical, physico-chemical and maturity parameters. In addition, the changes in water-soluble organic matter were assessed using chemical analytical methods and the excitation-emission matrix (EEM) fluorescence spectroscopy. The results obtained showed the viability of the co-composting process to obtain end-products with adequate maturity degree and physical characteristics for their potential use as substrates, except for the salt contents that can limit their use in some agricultural sectors.

Composting of the invasive species Arundo donax with sewage and agri-food sludge: Agronomic, economic and environmental aspects

This work evaluates several co-composting scenarios based on the use of Arundo donax biomass (AD) as bulking agent for the co-composting of sewage sludge (MS) and agri-food sludge (AS), to manage these organic wastes and to produce balanced organic fertilizers by optimizing the process. For this, six piles were prepared in commercial composting conditions, using AD in a range of 40%-80% (on a dry weight basis). Physico-chemical and chemical parameters and the thermal behaviour were evaluated during the process, as were the physical and chemical parameters of the final composts. The proportion of AD in the mixtures has a significant effect on the development of the thermophilic stage of composting, showing the piles with higher proportion of AD a quicker organic matter degradation. In addition, the evolution of the thermal indices R1 and R2 was different depending on the origin of the sludge used, indicating an increase in the relative concentration of more recalcitrant materials in the piles prepared with AS. The estimation of the global warming potential showed that the use of higher proportion of AD in the composting mixture may be a strategy to mitigate the emission of greenhouse gases during the composting process. Moreover, the end-products obtained had an additional marketable value, with a balanced nutrient content and a good degree of maturity, which indicates the viability of the composting process as a method for the stabilization of these organic wastes.

Duodenal membranes: a late diagnosis evidenced by foreign bodies

One of the causes of congenital incomplete duodenal obstruction is the presence of duodenal membranes. This condition requires a high index of suspicion for an early and accurate diagnosis. We present two cases of duodenal obstruction with initial diagnosis of foreign bodies that were surgically intervened and where incomplete duodenal membranes were an incidental finding. The clinical course of these patients had a different pattern than expected and thus, it is imperative to use a multidisciplinary approach in this group of patients and separate them from other subtypes of duodenal obstruction.

Determination of Vitamin D Status in a Population of Ecuadorian Subjects

INTRODUCTION

Vitamin D is a preprohormone known to play a key role in phosphocalcic metabolism; its main source comes from the synthesis at the skin level by ultraviolet (UV) radiation.

OBJECTIVE

The purpose of this study was to determine the levels of vitamin D in an Ecuadorian population.

MATERIALS AND METHODS

Retrospective study of Ecuadorian subjects from the city of Guayaquil, who had an initial study of 25 (OH)-D serum, as the indicator of Vitamin D status, in the period of 2015-2016.

RESULTS

A total of 269 Ecuadorian subjects were analyzed, with a mean age of 54.73 ± 16.58; 85% (229) were females and 15% (41) males; mean vitamin D was 27.29 ± 10.12 ng/dl [6.41-88.74]; 70% of the population showed levels below 30 ng/dL of vitamin D, whereas only 30% (81) had normal values. 69% (185) had levels between 29 and 10 ng/dl and 1% (3) levels below 10 ng/dl. High levels of vitamin D were evidenced in the summer months in relation to the winter months.

CONCLUSION

It is evident that, despite the location of Ecuador and the intensity of UV rays it receives throughout the year, Ecuadorian subjects have insufficient levels of vitamin D.

Agroindustrial compost as a peat alternative in the horticultural industry of Ecuador

This work was conducted in order to investigate the possibility of using different agroindustrial composts in the production of horticultural seedlings, thereby replacing part of the peat in the growing media. Three vegetable species differing in salt sensitivity - tomato (Solanum lycopersicum L. var. Malpica) (the least sensitive), courgette (Cucurbita pepo L. var. Mastil F1) (moderately sensitive) and pepper (Capsicum annuum L. var. Largo de Reus Pairal) (the most sensitive) - were grown in nine media containing three composts, prepared by co-composting vegetable waste (flower, broccoli or tomato waste) with laying hen manure and sawdust, as well as peat in various ratios. The proportions of the three composts in the mixtures elaborated with peat were 25%, 50% and 75% (v/v). A substrate of 100% peat was used as control. The experiment was arranged in a completely-randomised design, with two replicates per treatment, under greenhouse conditions. Prior to sowing, some physical, physico-chemical and chemical properties of the growing media were determined and the seed germination and fresh and dry weights of the aerial parts and roots of the seedlings were also measured, as well as the mineral composition of the aerial parts of the plants. In most cases, the addition of compost to the growing media produced an increase in the pH, salt content and macronutrient concentrations, in comparison to peat, whereas the physical properties of the compost based-substrates had values very similar to those of an ideal substrate. Also, multivariate analysis showed that the media prepared with flower waste compost, at all concentrations, and the medium with tomato waste compost at 25% were the most suitable substrates for the three plant species tested.

Windrow composting as horticultural waste management strategy - A case study in Ecuador

In Ecuador, enormous quantities of vegetable wastes are produced annually from the horticultural industries. Composting can be a feasible treatment to stabilise horticultural wastes and, thus, to improve their properties for use as organic fertilisers. In this study, two different piles were prepared, using laying hen manure and sawdust mixed with broccoli or tomato waste, respectively, and composted by the turned windrow composting system. Throughout the composting process, the temperature of the mixtures was monitored and physico-chemical and chemical properties and the degree of maturity were determined. Also, principal component analysis was used to interpret the data set of compost characteristics. In both piles, the temperature exceeded 55°C for more than 2weeks, which ensured maximum pathogen reduction. Organic matter (OM) losses followed a first-order kinetic equation in both piles. The final composts showed a suitable degree of stability and maturity and an absence of phytotoxins, as observed in the evolution and final values of the total organic carbon/total nitrogen ratio (Corg/NT<20), water-soluble organic carbon (Cw<1.7%), germination index (GI>50%) and cation exchange capacity (CEC>67meq (100g OM)(-1)). As well, the evolution of different humification indexes during composting was a good indicator of the OM humification process. The type of vegetable waste used influenced OM and NT mineralisation and the final properties of the composts, showing the mixture with tomato waste a higher fertilising capacity and less environmental problems.

Chemical, Thermal and Spectroscopic Methods to Assess Biodegradation of Winery-Distillery Wastes during Composting

The objective of this work was to study the co-composting process of wastes from the winery and distillery industry with animal manures, using the classical chemical methods traditionally used in composting studies together with advanced instrumental methods (thermal analysis, FT-IR and CPMAS ¹³C NMR techniques), to evaluate the development of the process and the quality of the end-products obtained. For this, three piles were elaborated by the turning composting system, using as raw materials winery-distillery wastes (grape marc and exhausted grape marc) and animal manures (cattle manure and poultry manure). The classical analytical methods showed a suitable development of the process in all the piles, but these techniques were ineffective to study the humification process during the composting of this type of materials. However, their combination with the advanced instrumental techniques clearly provided more information regarding the turnover of the organic matter pools during the composting process of these materials. Thermal analysis allowed to estimate the degradability of the remaining material and to assess qualitatively the rate of OM stabilization and recalcitrant C in the compost samples, based on the energy required to achieve the same mass losses. FT-IR spectra mainly showed variations between piles and time of sampling in the bands associated to complex organic compounds (mainly at 1420 and 1540 cm^-1) and to nitrate and inorganic components (at 875 and 1384 cm^-1, respectively), indicating composted material stability and maturity; while CPMAS ¹³C NMR provided semi-quantitatively partition of C compounds and structures during the process, being especially interesting their variation to evaluate the biotransformation of each C pool, especially in the comparison of recalcitrant C vs labile C pools, such as Alkyl /O-Alkyl ratio.

Analysis of the influence of variation factors on electrical conductivity of milk in Murciano-Granadina goats

The aim of this study was to obtain further knowledge on electrical conductivity (EC) of milk as a tool for detecting mastitis in goats. The effect of farm, parity, stage of lactation, and health status of the glands on EC, and the somatic cell count (SCC) of milk was analyzed. Additionally, relationships between EC and chemical composition and SCC were studied. Finally, characteristics of EC and SCC (sensitivity and specificity) as diagnostic tests used to detect mastitis were studied. One hundred and five Murciano-Granadina goats were enrolled in the study. Milk samples (by gland) were collected monthly for 7 mo on 3 farms in the southeastern Spain. To establish the health status, milk samples were aseptically collected before milking by gland. Foremilk (by gland) was collected to analyze EC, SCC, and chemical composition. Glands were classified according to the health status as free of mastitis, bacterial mastitis, or unspecific mastitis. The effects of farm, parity, and stage of lactation, as well as the interactions between health status and parity, parity and stage of lactation, and health status and stage of lactation were associated with EC. Changes in the milk's chemical composition (particularly of chloride ions) explained most of the variance in EC (R(2)=0.91). The strongest association between EC and SCC was found at SCC >2×10(6) cells/mL (r=0.42). The use of a single EC threshold for all animals and farms for detecting mastitis led to limited results for mastitis detection, which, in any case, favors negative predictive values over positive predictive values. This study revealed that factors, other than the health status, affecting EC hamper the use of an EC threshold for mastitis detection with sufficient specificity on all animals. Any detection system based on EC of milk should consider these factors, as well as specific variations for each of the animals.

Neoadjuvant radio chemotherapy in esophageal squamous cell carcinoma: Early results analysis of a 5-year experience

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Background: Optimized survival in oesophageal squamous cell carcinoma (OSCC) depends on complete surgical resection: prognostic impact of well-standardized techniques and per operative management in experienced groups has proven to be a key aspect. Multimodal treatment (MT) options are still controversial but particularly important in locally advanced disease apparently allowing better resectability. We perform an early evaluation of a MT protocol in locally advanced OSCC.

Methods: Survival and clinical response analysis of a cohort of pts selected between 01/01/2002 and 31/12/2007. Criteria: Locally advanced OSCC (T3/4); No distant metastases; Negative bronchoscopy; Age under 76y; No other known cancer; Surgical feasibility. Pts underwent a 5 week MT: Chemo – taxotere 20 mg/m2 IV, cysplatin 20 mg/m2 IV, 5-FU 425 mg/m2 iv (days 1,8,14,22 and 29); Radio- 40 Gy (days 1-5, 8-12, 14-19, 22-26 and 29-34) followed by surgery within 4 weeks.

Results: 57 pts (38% of all admitted) 8 fem and 49 male, aged < 50y = 11, 51-65y = 30 and > 65y = 16. Response: Complete pathological remission = 13; Partial clinical response with downstaging = 15; Minimal / no clinical response = 14; Disease progression / no surgery: 15. From the 42 pts operated, an “en bloc” osophagectomy with extended lymphadenectomy was possible in 36. The overall mean follow-up for resected pts was 16.9 months (CI 95%: 10.9-22.8). The median survival was 18 months for resected patients (CI 95%: 8.7-27.3) in contrast with 7 for all candidates to MT. There was a statistically significant difference in the survival of the 4 groups divided according to their response to MT, with clear advantage of the complete pathological remission achievers.

Conclusions: Short follow-up and series size does not allow definite conclusions. It seems nevertheless that only the group of full pathological remission and probably those that obtain a downstaging of their disease benefit from MT. Histopathological or molecular markers are required to identify target pts for neoadjuvant radio chemotherapy.

No significant financial relationships to disclose.

Influences of winery-distillery waste compost stability and soil type on soil carbon dynamics in amended soils

The application of organic materials to replenish soil organic matter and improve soil structure and fertility has become a common agronomic practice. This research deals with the effects of soil amendment with winery and distillery waste composts on organic carbon (C) mineralisation in two arable soils. A sandy-loam and clay-loam soil were treated and incubated with a number organic materials obtained from the co-composting of different proportions of grape stalk, grape marc, exhausted grape marc and vinasse, with sewage sludge or animal manure. Moreover, the effect of compost stability on C mineralisation dynamics was studied by applying organic materials from different stages of the composting process. The results obtained showed that the addition of exogenous organic matter stimulated microbial growth, enhanced soil respiration and increased water-extractable C contents in both soils, particularly in the days immediately following amendment. The initial composition of the different organic materials used, especially for the mature samples, and the texture of the receiving soil did not influence significantly the C mineralisation final values, with around 11-20% of the added organic C being mineralised over the first 140 days. However, the contribution of organic amendment to the labile organic C pool, maximum rates of soil respiration, as well as the extent of initial disturbance of the soil microbiota were all found to be related to the degree of organic matter stability. Moreover, irrespective of the type and stability of the organic amendment, the mineralogical composition of the receiving soil was found to significantly influence its resilience in such systems.

Use of chemometrics in the chemical and microbiological characterization of composts from agroindustrial wastes

Physico-chemical, chemical and microbiological parameters were studied in a set of fifteen different composts elaborated with agroindustrial wastes using two different composting systems (turning and static pile composting). To carry out the chemometric evaluation, multivariate statistical analysis techniques, such as hierarchical cluster analysis (HCA) and factorial analysis (FA) were used. Composts obtained showed suitable physico-chemical and chemical properties for their use as organic amendment and a good maturity degree. HCA allowed to classify the organic materials mainly in four groups: cluster A, cluster B, cluster C and unclustered composts; also, this statistical tool showed the lack of influence of the composting system in the final characteristics of these composts. On the other hand, through FA, it was possible to identify the principal variables associated to the composting of agroindustrial wastes in four factors that explained 72.3% of the variability.

The potential of near infrared reflectance spectroscopy (NIRS) for the estimation of agroindustrial compost quality

Composting is an environmentally friendly alternative for the recycling of organic wastes and its use is increasing in recent years. An exhaustive monitoring of the composting process and of the final compost characteristics is necessary to certify that the values of compost characteristics are within the limits established by the legislation in order to obtain a safe and marketable product. The analysis of these parameters on each composting batch in the commercial composting plant is time-consuming and expensive. So, their estimation in the composting facilities based on the use of near infrared reflectance spectroscopy (NIRS) could be an interesting approach in order to monitor compost quality. In this study, more than 300 samples from 20 different composting procedures were used to calibrate and validate the NIRS estimation of compost properties (pH, electrical conductivity (EC), total organic matter (TOM), total organic carbon (TOC), total nitrogen (TN) and C/N ratio, macronutrient contents (N, P, K) and potentially pollutant element concentrations (Fe, Cu, Mn and Zn)). The composts used were elaborated using different organic wastes from agroindustrial activities (GS: grape stalk; EGM: exhausted grape marc; GM: grape marc; V: vinasse; CJW: citrus juice waste; Alpeorujo: olive-oil waste; AS: almond skin; EP: exhausted peat; TSW: tomato soup waste; SMS: spent mushroom substrate) co-composted with manures (CM: cattle manure; PM: poultry manure) or urban wastes (SS: sewage sludge) The estimation results showed that the NIRS technique needs to be fitted to each element and property, using specific spectrum transformations, in order to achieve an acceptable accuracy in the prediction. However, excellent prediction results were obtained for TOM and TOC, successful calibrations for pH, EC, Fe and Mn, and moderately successful estimations for TN, C/N ratio, P, K, Cu and Zn.

Estimation of phosphorus content and dynamics during composting: use of near infrared spectroscopy

The content and chemical forms of P in compost are essential variables for its proper management with an agricultural purpose, especially considering the increasing P over-fertilization in agrosystems. In this study, the estimation of P content and dynamics in different composting scenarios was developed using near infrared reflectance spectroscopy (NIRS) coupled with a statistical tool for calibration, a penalized signal regression. Samples were analyzed on total P and partitioned using NaOH-solution (31)P NMR spectroscopy quantifying pyrophosphate, orthophosphate, orthophosphate diesters, phospholipids, and orthophosphate monoesters pools. According to the results obtained, total P content (r(2)=0.99 and root mean square error of cross-validation=0.53) and P forms can be estimated during composting using NIRS, as well as in the mature product, orthophosphate and orthophosphate monoesters being the most abundant P forms throughout the experiment. Penalized signal regression allows detecting the significant wavenumbers in each composting period, and also with the different P pools in the composting pile depending on time.

Utilisation of manure composts by high-value crops: safety and environmental challenges

The intensification in livestock production has increased the need of efficient treatments of waste streams especially to preserve as much as possible, the nutrients into the soil-plant system. Composting is a cheap, efficient and sustainable treatment for solid wastes that is always included in any manure treatment scenario. In this paper, an overview about the environmental and safety challenges of composting of manures is made considering the compost quality requirements established by the main demanding sectors. Co-composting and additive strategies are presented as feasible options for the improvement of compost quality. For quality evaluation of manure compost, the use of both classical and innovative instrumental techniques could increase our knowledge about added properties in compost, especially those related to organic matter stability.

Study of the evolution of organic matter during composting of winery and distillery residues by classical and chemometric analysis

The aim of the present paper is to evaluate the changes of organic matter during the composting process of fresh winery and distillery residues (WDR) by means of classical and chemometric analysis of (13)C cross-polarization magic angle spinning (CPMAS) NMR and Fourier transform infrared (FT-IR) spectra. (13)C NMR spectroscopy displayed a preferential biodegradation of carbohydrates as well as an accumulation of aliphatic chains (cutin- and suberin-like substances). This preferential biodegradation of the organic fractions reduces the landfill emission potential. Although the composition of the input mixture strongly affects the shape of the infrared (IR) spectra, typical bands of components can be selected and used to follow the composting process; that is, changes in the relative absorbances of the band of nitrate (at 1384 cm(-1)) and in the band of carbohydrates (at 1037 cm(-1)) have been observed. In addition, different chemometric tools, such as partial least-squares (PLS), interval PLS (iPLS), backward iPLS (biPLS), and genetic algorithm (GA), have been used to find the most relevant spectral region during the composting process. Chemometric analysis based on the combined and sequential use of iPLS and GA has been revealed as a very powerful tool for the detection in samples of the most relevant spectral region related to the composting process. From the obtained results, it can be concluded that CPMAS (13)C NMR supported by FT-IR could provide information about the evolution and characteristics of the organic matter during the composting process in order to avoid contamination problems after its use as amendment in agriculture or after landfilling.

Study of the composting process of winery and distillery wastes using multivariate techniques

Physico-chemical, chemical and biological parameters were studied throughout the composting process of four winery and distillery composts and the data set of compost characteristics was analysed using multivariate techniques: factorial analysis (FA) and linear discriminant analysis (LDA), in order to classify the different parameters studied and thus, to establish those that better describe the composting process of this type of wastes. Through factorial analysis (FA) of the parameters studied throughout the composting process, four components that explained 85.6% of the variability were established. The parameters associated to compost maturity, agronomic character, water-soluble fraction and ammonia and temperature increment were grouped in the components F1, F2, F3 and F4, respectively, which can reduce the number of determinations needed to ascertain the maturity and quality of the composts. In addition, the linear discriminant analysis on the factorial components makes possible to classify the four composts with a percentage of success around 95%.

Spent mushroom substrates as component of growing media for germination and growth of horticultural plants

This research work was conducted in order to investigate the possibility of using spent mushroom substrate (SMS) in the production of horticultural seedlings replacing part of the peat in the growing media. Three vegetable species with different salt sensitivities, the less sensitive being tomato (Lycopersicon esculentum var. Muchamiel), the moderately salt-sensitive being courgette (Cucurbita pepo L. var. Afrodite F1) and the most salt-sensitive being pepper (Capsicum annum L. var. Lamuyo F1) were grown in 12 media containing SMS of two types of mushroom (Agaricus bisporus (SMS-AB) and Pleurotus ostreatus (SMS-PO)) or a mixture of both 50% (v/v) (SMS-50), as well as peat in various ratios. The proportions of each residue in the mixtures elaborated with peat were 25%, 50%, 75% and 100% v/v residue. A substrate of 100% peat was used as control. The experiment was arranged in a completely-randomised design with two replicates per treatment under greenhouse conditions. Prior to sowing, some physical, physico-chemical and chemical properties of the growing media were determined and seed germination and fresh weight of seedling were also measured. In most of the cases, the addition of SMS to the growing media produced an increase in the pH values, salt contents, macro and micronutrient concentrations and a decrease in the water holding capacity contents in comparison to peat, whereas great differences were found in the air capacity values between SMS-based substrates and peat. Up to 75% SMS can be used in mixtures with peat for seed germination of the plant species studied. Regarding the most suitable SMS-based substrates for plant growth, any substrate could be used for tomato seedling production. However, all SMS-AB-based substrates and the media containing low dose of SMS-PO and SMS-50 were adequate for growth of courgette and pepper.

Evolution of the pathogen content during co-composting of winery and distillery wastes

The aim of this study was to monitor some microbial indicators and pathogen contents (sulphite reducers clostridia, total enterobacteriaceae, total coliforms, faecal coliforms (Escherichia coli), enterococci, Staphylococcus aureus and Salmonella spp.) throughout the co-composting of wastes from the winery and distillery industry with other organic residues, as well as the effect of the composting system used. Seven different piles using mixtures of winery-distillery wastes with other organic materials were prepared. P1 and P2 were made using grape stalk (GS), grape marc (GM), exhausted grape marc (EGM) and sewage sludge (SS), whereas in P3 and P4 were also used exhausted grape marc with cow manure (CW) and poultry manure (PM), respectively, using the Rutgers system. Additionally, P2 was watered with vinasse (V). The rest of piles (P5, P6 and P7) were prepared with grape marc, exhausted grape marc, cow manure and poultry manure, using the turning system. The effectiveness of the composting process to reduce the pathogen content was higher in the static aerated piles than in those elaborated with the turning. The relatively high temperatures (50-60 degrees C) reached in some of the piles produced a notable decrease in some microbial groups, such as total and faecal coliforms (E. coli), but the characteristics of the raw materials used notably influenced the pathogen contents of the end-product.

Salinity, organic content, micronutrients and heavy metals in pig slurries from South-eastern Spain

The increase in commercial pig production is an opportunity to reuse animal manures in arid and semiarid soils as a source of nutrients and organic matter. However, there are components in pig slurry that are potentially dangerous for the environment. In this study, pig slurries of 36 pig farms in South-eastern Spain were evaluated for salt content (electrical conductivity, chloride and sodium), organic load (BOD5 and COD), micronutrients (Fe, Cu, Mn and Zn), and heavy metals (Cd, Co, Cr, Ni and Pb). Except for electrical conductivity, Cu and Zn, components in pig slurries did not vary considerably between animal production stages, indicating similar management of diverse animal types. Assuming an application rate based on the maximum input of nitrogen from animal manure (210 kg total N/ha/yr), the estimates for soil annual load of Cl and Na, 415 kg/ha, could be a significant salinisation risk. Cu and Zn seemed to be the metals that could be accumulated most in soils where application of pig slurries is common (4 and 15 kg/ha/yr, respectively). The estimated heavy metal (Cd, Co, Cr, Ni and Pb) input to soils would be 260 g/ha/yr, with a relative contribution of Cr>Ni>Pb>Co>Cd.

Agrochemical characterisation of the solid by-products and residues from the winery and distillery industry

The winery and distillery industry produces a great quantity of residues, whose management and disposal are environmental problems due to their seasonal character and some polluting characteristics. The main solid by-products and residues generated are grape stalk, grape pomace or marc, wine lee, exhausted grape marc and winery sludge. In this study, 87 samples of winery and distillery residues were collected from different Spanish wineries and distilleries. Electrical conductivity, pH, total organic matter, organic carbon, polyphenols and contents of plant nutrients and heavy metals were determined. The purpose of this research was to study the composition of these wastes and to find relationships in order to use easily analysable parameters to estimate their composition. In general, the winery and distillery residues showed low pH (mean values ranged from 3.8 to 6.8) and electrical conductivity values (1.62-6.15 dS m(-1)) and high organic matter (669-920 g kg(-1)) and macronutrient contents, especially in K (11.9-72.8 g kg(-1)). However, a notable polyphenol concentration (1.2-19.0 g kg(-1)) and low micronutrient and heavy metal contents were also observed, some of these properties being incompatible with agricultural requirements. Therefore, conditioning treatments are necessary prior to possible use of these wastes. In all wastes, significant correlations were found between easily determined parameters, such as pH, electrical conductivity and total organic matter, and most of the parameters studied. The regression models obtained are also discussed.

Short-term carbon and nitrogen mineralisation in soil amended with winery and distillery organic wastes

The aim of this work was to study the influence of the organic wastes derived from the winery and distillery industry (grape stalk (GS), grape marc (GM), wine lees (WL) and exhausted grape marc (EG)) and the soil type (clayey-loam (S1), loam (S2) and sandy textured (S3)) on different soil characteristics, especially the carbon and nitrogen mineralisation. The evolution of C mineralisation fitted a first-order kinetic for all amended soils. An initial increase was observed in the specific respiration (qCO(2)) at the beginning of the experiment. However, afterwards, the evolution in the qCO(2) was to tend towards the values of the control soil due to the pattern of the soil to recover its initial equilibrium status. The addition of these materials in the soils produced a slight increase of the inorganic nitrogen content, except in the case of GS and EG in most of the studied soils. The use of GS as amendment produced an inhibition in the N mineralisation in the three types of soils studied. Organic matter mineralisation was probably influenced by soil type, the sandy soil favouring more the N and C mineralisation processes than the clayey-loam and loam soils.

Dissolved organic matter fractions formed during composting of winery and distillery residues: evaluation of the process by fluorescence excitation-emission matrix

The aim of the present paper is to assess the maturity degree reached by different samples of several mixtures from winery and distillery residues composted using the Rutgers composting system, by means of excitation-emission matrix (EEM) fluorescence spectroscopy. The composts were sampled once a week for about 200d. EEM spectra indicate the presence of different fluorophores. The fluorescence intensities of these peaks show trends related to the maturity of the composting samples selected. The "contour density" of EEM maps is strongly modified through time. We have used the quantitative method of fluorescence regional integration (FRI). The EEMs were delineated into five excitation-emission regions. The degree of compost maturity could be correlated with the percentage of the volumetric integration under the EEM within each region. Further refinement of these techniques should provide a relatively rapid method for assessing the suitability of the compost to soil application.

Co-composting of distillery and winery wastes with sewage sludge

The winery and distillery wastes (grape stalk and marc (GS and GM, respectively), wine lees (WL) and exhausted grape marc (EGM)) are produced in great amounts in the Mediterranean countries, where their treatment and disposal are becoming an important environmental problem, mainly due to their seasonal character and some characteristics that make their management difficult and which are not optimised yet. Composting is a treatment widely used for organic wastes, which could be a feasible option to treat and recycle the winery and distillery wastes. In this experiment, two different piles (pile 1 and 2) were prepared with mixtures of GS, GM, EG and sewage sludge (SS) and composted in a pilot plant by the Rutgers static pile composting system. Initially, GS, GM and EGM were mixed, the pile 1 being watered with fresh collected vinasse (V). After 17 days, SS was added to both piles as a nitrogen and microorganisms source. During composting, the evolution of temperature, pH, electrical conductivity, total organic C, total N, humic acid-like C and fulvic acid-like C contents, C/N ratio, cation exchange capacity and germination index of the mixtures were studied. The addition of V in pile 1 produced higher values of temperature, a greater degradation of the total organic C, higher electrical conductivity values and similar pH values and total N contents than in pile 2. The addition of this effluent also increased the cation exchange capacity and produced a longer persistence of phytotoxicity. However, both piles showed a stabilised organic matter and a reduction of the phytotoxicity at the end of the composting process.

Use of composted sewage sludge in growth media for broccoli

In this study, the use of composted sewage sludge (CSS) as a binary component with peat (P) in growth media for a horticultural crop, broccoli (Brassica oleracea var. Botryti cv. Marathon), was evaluated. Four treatments were established, based on the addition of increasing quantities of composted sewage sludge to peat (0%, 15%, 30% and 50%, v/v). Physical, physico-chemical and chemical analyses of the different mixtures of CSS and P were made. Plant growth, biomass production and macronutrient (N, P, K, Ca, Mg), micronutrient (Fe, Cu, Mn, Zn) and heavy metal (Pb, Ni, Cd, Cr) contents of plants were determined. The addition of CSS to P increased plant nutrient and heavy metal contents of plants and electrical conductivity (EC) and bulk density values of the substrates. The use of CSS did not affect the germination rate, even at 50% compost. For broccoli growth, the highest yield was obtained with the medium prepared by mixing the peat with 30% of compost; however, the mixture with the most sewage sludge compost (50%) had the greatest contents of macro and micronutrients.

Influence of olive mill wastewater in composting and impact of the compost on a Swiss chard crop and soil properties

The suitability of olive mill wastewater (OMW) for composting was studied by the addition of this liquid waste to a mixture of cotton gin waste and sewage sludge, and its composting was compared with that of another pile of similar composition, but without olive mill wastewater. Both piles were composted by the Rutgers static pile system in a pilot plant. To study the effects of both composts on plant yield and soil properties, a plot experiment was carried out with Swiss chard (Beta vulgaris L. var. cicla). Five treatments were applied: mineral fertiliser and two doses (30 and 60 tons ha(-1)) of both composts. The olive mill wastewater addition produced a compost with lower organic matter and nitrate concentrations, higher electrical conductivity, and a stabilised and humified organic matter similar to that of the compost produced without olive mill wastewater. The olive mill wastewater compost application to soil did not injure plants, producing a similar plant yield to both compost without olive mill wastewater and inorganic fertiliser. Also, the accumulation of potentially toxic heavy metals in plants cultivated with organic or mineral fertilisers did not reveal significant differences. The olive mill wastewater compost application to soil also improved the chemical and physicochemical properties of the soil.

Characterisation of the organic matter pool in manures

In this research, different types of animal manure were evaluated with respect to organic matter (OM), total organic carbon (C(ot)), total N (N(t)), C(ot)/N(t) ratio, water-soluble organic carbon (C(w)), organic N (N(org)), carbohydrates, C(w)/N(org) ratio, humic acid-like carbon (C(ha)), fulvic acid-like carbon (C(fa)), humification index ((C(ha)/C(ot))x100) (HI) and the C(ha)/C(fa) and NH(4)(+)-N/NO(3)(-)-N ratios. In comparison with the limits set by the Spanish legislation for organic fertilisers, most of the manures had high OM contents, moderate N(org) concentrations (except in the case of the chicken and pig manures where this parameter was high) and C(ot)/N(t) ratios above the value stated in the legislation. The study of the different fractions of organic matter showed that the horse, pig and rabbit manures had the greatest content of C(ot). However, the fraction of easily-biodegradable organic compounds (C(w)) was significantly higher in the horse, goat and chicken manures. The study also showed that, in most cases, the percentage of fulvic acid-like C was greater than that of the humic acid-like C, indicating that the organic matter of these wastes is not completely humified. Values of HI ((C(ha)/C(ot))x100) and C(ha)/C(fa) ratio in the studied manures were not significantly different. Regarding the parameters related to the organic matter stability such as C(w), carbohydrates and the C(ot)/N(t), C(w)/N(org) and NH(4)(+)-N/NO(3)(-)-N ratios, it has been determined that the organic matter of these materials was not completely stabilised. The heterogeneity in OM composition of the studied manures did not allow the formulation of simple equations for evaluation of the composition of these wastes from easily-determined parameters.

Uses of winery and distillery effluents in agriculture: characterisation of nutrient and hazardous components

Twenty-one samples of winery and distillery effluents were collected from different Spanish winery and distillery industries. Electrical conductivity, pH, redox potential, density, organic charge (chemical oxygen demand, biological oxygen demand, total, volatile and suspended solids, oxidisable organic C and polyphenols) and contents of plant nutrients and heavy metals were analysed. The aim of this work was to study the composition of these effluents and to find relationships which would make it possible to use easily determined parameters to estimate their composition. The winery wastewater (WW) and vinasse (V) showed an acidic pH, a high organic load and notable polyphenol, macronutrient, micronutrient and heavy metal contents. Some of these properties are not compatible with agricultural requirements; therefore, conditioning treatment of these liquid wastes is necessary to produce a safe, stable and easily manageable end product. Generally, in both effluent types, significant correlations were found between easily analysable parameters, such as suspended, volatile and total solids, pH, electrical conductivity, density and redox potential, and most of the parameters studied. The linear regression equations obtained permitted an immediate characterisation of the WW and V samples using these parameters.

Estimation of nutrient values of pig slurries in Southeast Spain using easily determined properties

The contents of available nutrients in pig slurries are not easy to quantify in situ without laboratory facilities, but chemical analyses using standard laboratory methods also take time and are costly and not practical for most farms. Thus, when animal slurries are applied to land, their fertiliser potential is often unknown. In addition, in the last years, the changes in the management of industrial piggeries has changed the nature of the pig slurries vg. decrease of the dry matter content, and consequently the methods and equations used for estimating the nutrient contents in these residues must be checked. In our study, slurry samples were collected from the storage tanks of 36 commercial farms in Southeast Spain. Samples were analysed for pH, electrical conductivity (EC), redox potential (RP), specific density (D), total solids (TS), sedimentable solids (SS), biological oxygen demand (BOD(5)), chemical oxygen demand (COD), total nitrogen (TKN), ammonium nitrogen (AN), organic nitrogen (ON), and total contents of phosphorus, potassium, calcium and magnesium. Relationships between major nutrient levels of pig slurries and a range of physical and chemical properties were investigated. We also analysed the variability of pig slurries according to the production stage. TKN, AN and K were closely related to EC. The P content in slurries was related more closely to solids-derived parameters such as D. The use of multiple properties to estimate nutrient contents in pig slurries, especially for AN and K, seemed unnecessary due to the limited improvement achieved with an additional property. Therefore, electrical conductivity seemed to be the most appropriate single, easily determined parameter for estimation of total and ammonium nitrogen and potassium in pig slurries, with more than 83% of the variance explained. P seemed to be the worst key nutrient for estimation using any easily determined parameter.

Strategies for fed-batch cultivation of t-PA producing CHO cells: substitution of glucose and glutamine and rational design of culture medium

A strategy for fed-batch cultivation of t-PA producing recombinant CHO cells is presented, based on the substitution of glucose and glutamine for slowly metabolized nutrients and in a rational design of the medium. Media for the batch and fed stages were based on the cell specific amino acid requirements, which allowed a more accurate determination of the initiation of the fed stage and the frequency of nutrient addition from then on. Salt concentration was also reduced in both media to avoid an increase in osmolality. As a consequence of this rational design, most amino acid did not accumulate significantly during the fed stage, as usually occurs when their supply is not based on cell requirements; also, lower amounts of by-products were obtained when osmolality level was kept low, that altogether increased viability, longevity and t-PA production when compared with a reference batch culture. Alternating glucose and galactose during the fed stage, allowed lactate detoxification of the cells through their own metabolism. This allowed an increase in cell growth and cell viability with respect to a fed-batch culture in which only glucose was used in the fed stage.

Bio-degradation of olive mill wastewater sludge by its co-composting with agricultural wastes

The use of maize straw (MS) or cotton waste (CW) as bulking agents in the composting of olive mill wastewater (OMW) sludge was compared by studying the organic matter (OM) mineralisation and humification processes during composting and the characteristics of the end products. Both composts were prepared in a pilot-plant using the Rutgers static-pile system. The use of CW instead of MS to compost OMW sludge extended both the thermophilic and bio-oxidative phases of the process, with higher degradation of polymers (mainly lignin and cellulose), a greater formation of nitrates, higher total nitrogen losses and a lower biological nitrogen fixation. The CW produced a compost with a more stabilised OM and more highly polymerised humic-like substances. In the pile with CW and OMW sludge, OM losses followed a first-order kinetic equation, due to OM degradation being greater at the beginning of the composting and remaining almost constant until the end of the process. However, in the pile with MS and OMW sludge this parameter followed a zero-order kinetic equation, since OM degraded throughout the process. The germination index indicated the reduction of phytotoxicity during composting.

Effects of olive mill wastewater addition in composting of agroindustrial and urban wastes

In order to study the suitability of olive mill wastewater (OMW) for composting, this liquid waste was added to two different mixtures of agroindustrial and urban wastes and the composting process was compared with two other piles of similar composition, but without OMW. These four piles were studied in a pilot plant using the Rutgers static pile system. The addition of OMW produced a greater proportion of degradable organic matter or a higher degradation rate, higher electrical conductivity values, greater losses of total N and lower nitrification than in piles without OMW. Its addition also restricted the increase of the cation exchange capacity and provoked the appearance of phytotoxicity or a longer persistence of phytotoxicity. However, in general, all the composts showed increases in the cation exchange capacity, the percentage of humic acid-like carbon, the polymerisation ratio of these humic substances (which revealed that the organic matter had been humified during composting) and the germination index, the latter indicating the reduction of phytotoxicity during the process.

Respiratory effects of halothane in a patient with refractory status asthmaticus

We describe the case of a 36 year old patient who was admitted to the intensive care unit (ICU) for an acute asthma attack that failed to respond to conventional treatment and required mechanical ventilation. The patient's condition improved after halothane was administered; treatment with this inhalational anaesthetic lasted 7 h, and the beneficial effect was obtained by employing concentrations between 0.5 and 2%. Under constant mechanical ventilator settings, a highly significant linear correlation between peak airway pressure and arterial pCO(2)(r: 0.98 P<0.001) was observed. The decrease in p(a)CO(2)induced by halothane may be explained by the diminished dead space that results from the drop in peak airway pressure. Arterial hypotension, which improved with inotropic agents, was the only complication that seemed related to the inhaled anaesthetic. The patient was extubated 24 h after her arrival to the ICU and discharged 72 h later. A causal relationship between the administration of halothane and clinical improvement is suggested.

[Morphometry of Sanguinolaria cruenta (Bivalvia: Psammobidae) in Tucacas Beach, Falcón, Venezuela)]

Three hundred and twelve shells of Sanguinolaria cruenta were collected in May 1999 in a sandy beach in Tucacas, Falcón, Venezuela. For each shell, antero-posterior length (Lap), overall height (Al), wide (An), weight (Pe), valves area (Arv), anterior length (La) and dorsal height (Ad) were measured. The descriptive statistic of the studied individuals, allows to appreciate that the variables that are good as parameters for the taxonomic description of S. cruenta are: Lap, Al, An, La y Ad, given their little variability. The maximum class frequencies is 41-70 mm for Lap (91% of the population). Analysis of data determined relationships of Lap to An, Lap to La were isometric (Lap = 0.98078 An + 1.50456 and Lap = 0.98052 La + 5.25840, respectively), whereas the other relationships indicate allometric growth.

Early introduction of cereals into children's diets as a risk-factor for grass pollen asthma

BACKGROUND

The prevalence of asthma has increased from the 1950s to the 1990s. The relationship between diet and asthma is an area of controversy that has never been fully evaluated. Attempts at dietary prevention of asthma have produced conflicting results. We have recently identified allergens from cereals that show cross-reactivity with proteins in grass pollen. An early intake of cereals in the diet during early life might cause IgE sensitization to cereals. It is not known whether such sensitization predisposes the development of allergy to pollen.

METHODS

To test this hypothesis, a cross-sectional study and an observational case-control analysis of reviewed data were carried out on 16381 patients who had been admitted to our Allergy Unit between 1989 and 1999. All the patients underwent allergy tests to identify asthma risk-factors. All information in our data base was analysed using the SPSS computer system.

RESULTS

There has been an increase of 7.8% in incidences of allergic asthma and a 7.3% increase in asthma due to grass pollen in the last decade. Grass-pollen asthma was associated with sensitization to cereals. The early introduction of cereals in the diet of children was found to be a risk factor for grass-pollen asthma (OR = 5.95; 95% CI 3.89-9.10).

CONCLUSIONS

These findings document the progression of allergic asthma during a decade in a large sample of people who were influenced by similar environmental conditions and studied with the same diagnostic methods. This study represents the largest database of patients in which a common food is shown to be a risk factor for asthma.

Nitrogen transformation during organic waste composting by the Rutgers system and its effects on pH, EC and maturity of the composting mixtures

The evolution of the different forms of nitrogen during the composting of several wastes was studied, as well as its relation to the pH, electrical conductivity and parameters of maturity of the composts obtained. Four mixtures were prepared from different organic materials: sewage sludge, municipal solid waste, brewery sludge, sorghum bagasse, cotton waste and pine bark. The evolution of the different forms of nitrogen during composting depended on the material which supplied the nitrogen to the mixtures and the organic matter (OM) degradation rate during composting. The greatest concentration of ammonium was observed during the first weeks of composting, coinciding with the most intense period of OM degradation, and ammonium then decreased gradually to reach final values of below 0.04%. The use of urea as a nitrogen source in the mixtures led to high ammonium levels during the first weeks as a result of its rapid hydrolysis. The nitrification process began only when the temperature of the mixtures had dropped below 40 degrees C and its intensity depended on the quantity of ammonium present when the process began. The highest concentrations of NO3-N were always produced at the end of maturation, reaching values of 0.52%, 0.53%, 0.12% and 0.20% in the four mixtures studied. Nitrogen losses during composting depended on the materials used and on the pH values of the mixtures. Mixtures with the highest lignocellulose content showed the lowest losses (below 25%), while those containing municipal solid waste lost more than 40% of the initial content. Statistically significant correlations at a high probability level were found between the NO3-N concentration and pH and electrical conductivity. confirming that nitrification was responsible for the falling pH values and increasing electrical conductivity. The ratio of NH4-N and NO3-N concentrations was shown to be a clear indicator of the maturity of the mixtures during composting, the final values of 0.08, 0.04, 0,16 and 0.11 for the four mixtures being equal to, or below the maximum value established as a maturity index in other materials.

[Pulmonary diffusion of carbon monoxide in 2 clinical situations: bronchial asthma and diabetes mellitus]

OBJECTIVE

The aim of our work has been the study and comparison of diffusion capacity of CO (DLCO) in two different clinical situations: bronchial asthma and diabetes mellitus.

METHOD

We have studied 16 control subjects, 38 patients with bronchial asthma and 65 patients with diabetes mellitus. We performed CO pulmonary diffusion tests by single breath method to determine two components: membrane diffusion factor (Dm) and pulmonary capillary blood volume (Vc).

RESULTS

We have found a positive correlation of FEV1 with Dm. The bronchial asthma group had a lower FEV1 and FEF25-75% and an increase in DLCO, Dm and Vc, with respect to the control group. The diabetes mellitus group presented a decrease in CVF, FEV1, DLCO and Vc, with respect to the control group. The bronchial asthma group showed a lower ratio of Dm/Vc than the control and diabetes groups.

CONCLUSIONS

The bronchial asthma patients have an increase in CO pulmonary diffusion, membrane diffusion factor and pulmonary capillary volume. However, the diabetes mellitus patients present a decrease in CO pulmonary diffusion mainly due to pulmonary capillary volume.

[Environmental contamination with Toxocara sp. eggs in public squares and parks from Santiago, Chile, 1999]

Most of cases of visceral larva migrans syndrome are caused by Toxocara canis larvae. Man acquires the infection by accidental ingestion of ripe eggs of the helminth. In order to find out the frequency of the presence of Toxocara sp. eggs in dog fecal specimens from public places of Santiago city in 1999 july-september a study was carried out in 84 squares and 12 parks from 32 counties. Three fecal samples were collected in each of these places, making a total of 288. Each sample was processed according to a modified Telemann method and three smears of each were microscopically examined. Toxocara sp. eggs were found in 39 (13.5%) fecal specimens. In 28/84 (33.3%) squares and in 8/12 (66.7%) parks these eggs were detected. These results make necessary the control of dogs and cats populations with the aim of reduce the presence of animals without responsible owners. It should be advisable to prevent dogs and cats defecation in public areas grounds, trying to exclude these animals from recreation areas.

Improvement of CHO cell culture medium formulation: simultaneous substitution of glucose and glutamine

The formulation of the culture medium for a Chinese hamster ovary (CHO) cell line has been investigated in terms of the simultaneous replacement of glucose and glutamine, the most commonly employed carbon and nitrogen sources, pursuing the objective of achieving a more efficient use of these compounds, simultaneously avoiding the accumulation of lactate and ammonium in the medium. The key factor in this process is the selection of compounds that are slowly metabolized. Among the different compounds studied, galactose and glutamate provide the best results, allowing support of cell growth with an optimal balance between nutrient uptake and cell requirements and the generation of minimal quantities of lactate and ammonium. The attained results also highlight the capacity of the cells to redistribute their metabolism as a response to the changes in medium composition.

Modification of glucose and glutamine metabolism in hybridoma cells through metabolic engineering

The present work describes the genetic modification of a hybridoma cell line with the aim to change its metabolic behaviour, particularly reducing the amounts of ammonia and lactate produced by the cells. The cellular excretion of ammonia was eliminated by transfection of a cloned glutamine synthetase gene. The metabolic characterisation of the transformed cell line includes the analysis of the changes introduced in its intracellular metabolic fluxes by means of a stoichiometric model. Furthermore, the reduction of lactate accumulation was attempted through an antisense mRNA approach, aiming to generate a rate limiting step in the glycolytic pathway, thus lowering the glucose consumption rate. The physiological results obtained with the transformed cells are discussed. A maximum reduction of about 47% in the glucose consumption rate was obtained for one of the transformations. However a main drawback was the lack of stability of the transformed cells.