Effect of an individualized versus standard pneumoperitoneum pressure strategy on postoperative recovery: a randomized clinical trial in laparoscopic colorectal surgery.

BACKGROUND: It remains uncertain whether individualization of pneumoperitoneum pressures during laparoscopic surgery improves postoperative recovery. This study compared an individualized pneumoperitoneum pressure (IPP) strategy with a standard pneumoperitoneum pressure (SPP) strategy with respect to postoperative recovery after laparoscopic colorectal surgery. METHODS: This was a multicentre RCT. The IPP strategy comprised modified patient positioning, deep neuromuscular blockade, and abdominal wall prestretching targeting the lowest intra-abdominal pressure (IAP) that maintained acceptable workspace. The SPP strategy comprised patient positioning according to the surgeon's preference, moderate neuromuscular blockade and a fixed IAP of 12 mmHg. The primary endpoint was physiological postoperative recovery, assessed by means of the Postoperative Quality of Recovery Scale. Secondary endpoints included recovery in other domains and overall recovery, the occurrence of intraoperative and postoperative complications, duration of hospital stay, and plasma markers of inflammation up to postoperative day 3. RESULTS: Of 166 patients, 85 received an IPP strategy and 81 an SPP strategy. The IPP strategy was associated with a higher probability of physiological recovery (odds ratio (OR) 2·77, 95 per cent c.i. 1·19 to 6·40, P = 0·017; risk ratio (RR) 1·82, 1·79 to 1·87, P = 0·049). The IPP strategy was also associated with a higher probability of emotional (P = 0·013) and overall (P = 0·011) recovery. Intraoperative adverse events were less frequent with the IPP strategy (P < 0·001) and the plasma neutrophil-lymphocyte ratio was lower (P = 0·029). Other endpoints were not affected. CONCLUSION: In this cohort of patients undergoing laparoscopic colorectal surgery, an IPP strategy was associated with faster recovery, fewer intraoperative complications and less inflammation than an SPP strategy. Registration number: NCT02773173 ( http://www.clinicaltrials.gov).

ANTECEDENTES: No se sabe con certeza si individualizar las presiones del neumoperitoneo durante la cirugía laparoscópica mejora la recuperación postoperatoria. Comparamos una estrategia con individualización de la presión del neumoperitoneo (individualised pneumoperitoneum pressure, IPP) frente a una estrategia con presión estándar del neumoperitoneo (standard pneumoperitoneum pressure, SPP) respecto a la recuperación postoperatoria tras cirugía colorrectal laparoscópica. MÉTODOS: Ensayo clínico aleatorizado multicéntrico. La estrategia IPP consistió en una modificación de la posición, bloqueo neuromuscular profundo, y una distensión de la pared abdominal conseguida con la presión intraabdominal (intra-abdominal pressure, IAP) más baja en la que el espacio quirúrgico operativo siguiera siendo aceptable. La estrategia SPP consistió en una posición de acuerdo con la preferencia del cirujano, bloqueo neuromuscular moderado, e IAP fija de 12 mm Hg. El resultado primario fue la recuperación fisiológica postoperatoria, evaluada mediante la escala de calidad en la recuperación postoperatoria (Postoperative Quality of Recovery Scale, PQRS). Los resultados secundarios incluyeron la recuperación en otros dominios y la recuperación global, la aparición de complicaciones intraoperatorias y postoperatorias, duración de la estancia hospitalaria, y los valores de los marcadores inflamatorios séricos durante tres días postoperatorios. RESULTADOS: De un total de 166 pacientes, 85 recibieron una estrategia IPP y 81 una estrategia SPP. La estrategia IPP se asoció con una elevada probabilidad de recuperación fisiológica (razón de oportunidades, odds ratio OR, 2,8 (i.c. del 95% 1,2-6,4); P = 0,017, razón de riesgo, 1,8 (i.c. del 95% 1,7-1,9), P = 0,05)). La estrategia IPP también se asoció con una elevada probabilidad de recuperación emotiva (P = 0,013) y global (P = 0,011). Los eventos adversos intraoperatorios fueron menos frecuentes con la estrategia IPP (P < 0,001) y la tasa neutrófilo-linfocito fue más baja (P = 0,029). No se observaron cambios en otras variables. CONCLUSIÓN: En esta cohorte de pacientes sometidos a cirugía colorrectal laparoscópica, una estrategia IPP se asoció con una recuperación más rápida, menos complicaciones intraoperatorias y menos inflamación en comparación con una estrategia SPP.

Retrospective observational study on safety of sedation for colonoscopies in ASA I and II patients performed by a nurse and under the supervision of anesthesiology.

INTRODUCTION: Out of operating room sedation with propofol by non-anaesthesiologists (Non Anaesthesiologist Administration of Propofol: NAAP) is a growing practice. This is due to the increase in minimally invasive diagnostic and therapeutic procedures requiring sedation, and the difficulty of anaesthesiology services to respond adequately to this demand. OBJECTIVE: The main objective of this study is to assess the safety of a programme of nurse sedationist-administered target controlled infusion (TCI) of propofol in colonoscopies supervised by anaesthesiologists. MATERIAL AND METHODS: Over a period of 6 months, all ASA I and II patients who required colonoscopy and met the inclusion criteria were included in the study. A total of 381 colonoscopies were performed. Episodes of desaturation, hypo- or hypertension, bradycardia or tachyarrhythmia and the need for anaesthesiology assistance during sedation were analysed. After the procedure, patient satisfaction was assessed on a scale of 1-5, and pain was assessed on a numerical verbal scale of 1-5. RESULTS: A small percentage (5%) of patients presented oxygen saturation of less than 90%, without requiring mask ventilation; 7.35% presented hypotension, 3.94% presented bradycardia, and the supervising anaesthesiologist was called in 22% of cases. Patient satisfaction at the end of the procedure was 4.27 out of 5. CONCLUSION: Sedation during colonoscopy in ASA I and II patients following an agreed protocol can be safely administered by nurse sedationists under the supervision of an anaesthesiologist.

Assessing the effects of severe heat treatment of milk on calcium bioavailability: in vitro and in vivo studies.

Thermal processing of milk is a common practice. As milk is the main source of dietary calcium, this study aimed to assess the effects of overheating milk on calcium availability. Thus, thermally damaged milk (overheated, OH, milk; 3 cycles of sterilization at 116 °C, 16 min) was compared with UHT milk (150 °C, 6s) in 2 types of assays: in vitro and in vivo (rats). In addition, the greater Maillard reaction rate associated with thermal treatment in OH milk was confirmed by determining specific (furosine) and unspecific markers (CieLab color). A negative effect on calcium solubility was observed after in vitro digestion of OH milk compared with UHT milk. Feeding rats the diet containing OH milk as the protein source led to significantly lower values of apparent calcium absorption and retention than those found among animals fed the UHT milk diet. Whereas reducing the absorption appears to result mainly from the decreased food intake, the negative effect on retention seems to be due to factors derived from milk thermal damage, such as the formation of Maillard reaction products. It was concluded that milk-processing conditions warrant special attention to prevent impaired dietary calcium utilization. This may be especially important in situations where milk and dairy products are the main dietary components, such as in early infancy.

Correction to: An individualised versus a conventional pneumoperitoneum pressure strategy during colorectal laparoscopic surgery: rationale and study protocol for a multicentre randomised clinical study.

After publication of our article [1] the authors have notified us that there are changes in the primary outcome and the statistical analysis plan of the study.

An individualised versus a conventional pneumoperitoneum pressure strategy during colorectal laparoscopic surgery: rationale and study protocol for a multicentre randomised clinical study.

BACKGROUND: A recent study shows that a multifaceted strategy using an individualised intra-abdominal pressure titration strategy during colorectal laparoscopic surgery results in an acceptable workspace at low intra-abdominal pressure in most patients. The multifaceted strategy, focused on lower to individualised intra-abdominal pressures, includes prestretching the abdominal wall during initial insufflation, deep neuromuscular blockade, low tidal volume ventilation settings and a modified lithotomy position. The study presented here tests the hypothesis that this strategy improves outcomes of patients scheduled for colorectal laparoscopic surgery. METHODS: The Individualized Pneumoperitoneum Pressure in Colorectal Laparoscopic Surgery versus Standard Therapy (IPPCollapse-II) study is a multicentre, two-arm, parallel-group, single-blinded randomised 1:1 clinical study that runs in four academic hospitals in Spain. Patients scheduled for colorectal laparoscopic surgery with American Society of Anesthesiologists classification I to III who are aged > 18 years and are without cognitive deficits are randomised to an individualised pneumoperitoneum pressure strategy (the intervention group) or to a conventional pneumoperitoneum pressure strategy (the control group). The primary outcome is recovery assessed with the Post-operative Quality of Recovery Scale (PQRS) at postoperative day 1. Secondary outcomes include PQRS score in the post anaesthesia care unit and at postoperative day 3, postoperative complications until postoperative day 28, hospital length of stay and process-related outcomes. DISCUSSION: The IPPCollapse-II study will be the first randomised clinical study that assesses the impact of an individualised pneumoperitoneum pressure strategy focused on working with the lowest intra-abdominal pressure during colorectal laparoscopic surgery on relevant patient-centred outcomes. The results of this large study, to be disseminated through conference presentations and publications in international peer-reviewed journals, are of ultimate importance for optimising the care and safety of laparoscopic abdominal surgery. Selection of patient-reported outcomes as the primary outcome of this study facilitates the translation into clinical practice. Access to source data will be made available through anonymised datasets upon request and after agreement of the Steering Committee of the IPPCollapse-II study. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02773173 . Registered on 16 May 2016. EudraCT, 2016-001693-15. Registered on 8 August 2016.

Estudio observacional retrospectivo sobre la seguridad de la sedación para colonoscopias en pacientes ASA I y II realizada por enfermería y tutelada por anestesiología / Retrospective observational study on safety of sedation for colonoscopies in ASA I and II patients performed by a nurse and under the supervision of anesthesiology

Introducción: La sedación con propofol por no anestesiólogos es una práctica creciente en áreas fuera de quirófano resultado del incremento de procedimientos diagnóstico-terapéuticos mínimamente invasivos que precisan sedación y de la dificultad de los servicios de anestesiología para responder adecuadamente a esta demanda. Objetivo: El objetivo principal de este estudio es valorar la seguridad de un programa de sedación para colonoscopias administrada por enfermería formada y tutelada por anestesiólogos, aplicando un protocolo de sedación con sistemas Target Controlled Infusion. Material y métodos: Durante un periodo de 6 meses se incluyeron en el estudio todos los pacientes ASA I y II que precisaron la realización de una colonoscopia programada y cumplían los criterios de inclusión. Se realizaron 381 colonoscopias. En el procedimiento se analizaron los episodios de desaturación, hipo- o hipertensión, bradicardia o taquiarritmia y la necesidad de asistencia por anestesiología. Tras el procedimiento se evaluó en una escala de 1 a 5 el nivel de satisfacción y el dolor mediante escala verbal numérica de 0 a 10. Resultados: El 5% de los pacientes presentó una saturación de oxígeno menor del 90% sin requerir ventilación con máscara; el 7,35% presentó hipotensión, el 3,94% bradicardia y fue necesario consultar al anestesiólogo responsable en el 22% de los casos. El grado de satisfacción alcanzado por los pacientes al final del proceso fue de 4,27 sobre 5. Conclusión: La sedación durante colonoscopias, en pacientes ASA I y II, siguiendo un protocolo consensuado puede ser administrada de forma segura por personal de enfermería tutelado por anestesiología.(AU)

Introduction: Out of operating room sedation with propofol by non-anaesthesiologists (Non Anaesthesiologist Administration of Propofol) is a growing practice. This is due to the increase in minimally invasive diagnostic and therapeutic procedures requiring sedation, and the difficulty of anaesthesiology services to respond adequately to this demand. Objective: The main objective of this study is to assess the safety of a programme of nurse sedationist-administered target controlled infusion of propofol in colonoscopies supervised by anaesthesiologists. Material and methods: Over a period of 6 months, all ASA I and II patients who required colonoscopy and met the inclusion criteria were included in the study. A total of 381 colonoscopies were performed. Episodes of desaturation, hypo- or hypertension, bradycardia or tachyarrhythmia and the need for anaesthesiology assistance during sedation were analysed. After the procedure, patient satisfaction was assessed on a scale of 1 to 5, and pain was assessed on a numerical verbal scale of 1 to 5. Results: A small percentage (5%) of patients presented oxygen saturation of less than 90%, without requiring mask ventilation; 7.35% presented hypotension, 3.94% presented bradycardia, and the supervising anaesthesiologist was called in 22% of cases. Patient satisfaction at the end of the procedure was 4.27 out of 5. Conclusion: Sedation during colonoscopy in ASA I and II patients following an agreed protocol can be safely administered by nurse sedationists under the supervision of an anaesthesiologist.(AU)

Dietary calcium utilization among a group of Spanish boys aged 11-14 years on their usual diets.

Adolescence constitutes a period of nutritional vulnerability due to increased dietary requirements for growth and development and special dietary habits. A pilot trial was performed to evaluate the dietary calcium utilization among a sample of Spanish boys on their usual diets, in which the calcium intake and consumption of dairy products were as well examined. Nutrient and food intake was recorded using a 24-h dietary recall and a 2-d food consumption record for 21 subjects aged 11-14 years. Dietary calcium utilization was assessed by means of calcium intake in food and calcium output in faeces and urine as measured by flame atomic absorption spectrophotometry. Overall intake of dairy products was 399.3 +/- 22.1 g/d, and the single most consumed item was milk (72% of the total). An inverse relationship was found between dairy product consumption at breakfast (55% of the total) and BMI (p = 0.016, r = -0.5168). Dairy products contributed the majority of dietary calcium (66.9%). Mean calcium intake was 881.7 +/- 39.9 mg/d, 88% of the recommended value for Spanish adolescents. Net calcium absorption (271.7 +/- 51.7 mg/d) and retention (170.6 +/- 50.9 mg/d) seemed not to be sufficient to meet growth demands during puberty. The results shown that adolescents of the study absorbed 31% of dietary calcium and retained nearly 20% of the total intake, but dietary calcium intake and consumption of dairy products failed to meet recommended values. Optimizing calcium intake is of crucial importance among adolescents, to maximize calcium retention and to help prevent osteoporosis in later life.

Several aspects of mineral/protein nutrition in relation to consumption of an oil involved in the toxic syndrome.

An oil involved in the 'toxic syndrome' and two similar mixtures of oils, one with and the other without added oleoanilides, were studied for their effects on the utilization of protein, calcium, magnesium, phosphorus, sodium, potassium and zinc. Forty-eight female Wistar rats initially weighing about 75 g were fed for 28 days on the same semi-synthetic diet containing: virgin olive oil, or a mixture of canbra oil (50%), refined olive-pomace oil (20%), grapeseed oil (20%) and animal fat (10%), or the same dietary mixture supplemented with either 700 ppm oleoanilides or the alleged toxic oil. Weight, food intake and nutritional balances were monitored. The food intake of the animals fed the toxic oil began to decrease at the end of the trial, producing a reduction in the amount of nutrients ingested, but no weight loss. This oil also negatively affected the digestion of protein, potassium, sodium and zinc, the mechanism of which, in the case of the first two, appears to be related to the source of the fat. It also decreased metabolic utilization while favouring protein catabolism and the elimination of phosphorus, magnesium and potassium. No substantial modifications were noted in the animals' bones.

Effects of consuming toxic oils and oleoanilides on fat digestibility and adipose tissue composition of rats.

An oil implicated in the Spanish "toxic syndrome" was studied for its effect on fat digestibility and adipose-tissue composition in rats. The effects produced by the mixture of oils and those induced by the presence of oleoanilides were assessed separately. For 4 wk, Wistar rats were fed diets containing either a mixture of oils similar to that constituting the toxic oil, the same mixture of oils supplemented with oleoanilides, or the toxic oil (which also contained oleoanilides) and were then compared with a group fed olive oil. Food consumption fluctuated sharply in the group fed the toxic oil, falling significantly in the last week of the study. The digestibility coefficient of the various fats was similar, although the rats fed the toxic oil did absorb less fat because of the lower intake. The nitrogen content of the periovarian adipose tissue was highest in the rats fed the toxic oil, and the adipose-tissue fatty acids most affected by this treatment were linoleic and linolenic acid. The delta-9 desaturase activity, measured in terms of the C16:1/C16:0 and C18:1/C18:0 ratios, was significantly less in the group fed the toxic oil, which suggests functional modifications of the adipocyte related to lipogenesis.

Influence of heat treatment of casein in presence of reducing sugars on Zn solubility and Zn uptake by Caco-2 cells after in vitro digestion.

The effect of the heat treatment of casein in presence of reducing sugars on some aspects of Zn availability was investigated. Samples were prepared by mixing casein with glucose-fructose, and were used unprocessed (C) or heated (HC). Changes in Zn speciation after the in vitro digestion of the samples, both as part of a diet and in isolation, were studied. The uptake of soluble Zn from the digested samples was investigated in Caco-2 cells. After in vitro digestion, the percentage of precipitated Zn was significantly higher with the HC sample, both when digested alone and as a part of the diet. In assays with Caco-2 cells, a significant decrease in Zn uptake was observed when the uptake buffer contained the sample C digest, by comparison with the control buffer, without casein digest. When the digested heated mixture was added, Zn uptake by the cells was significantly lower than in either of the two other cases. It may be concluded that the heat treatment of casein in the presence of glucose-fructose has a negative effect on Zn availability because, after in vitro digestion, Zn insolubilization was enhanced and Zn uptake by the enterocyte was impaired, compared with the unheated mixture. In addition, the usefulness of Caco-2 cells in this kind of research has been shown.

The effects of season and stage of pregnancy on 25-hydroxy-vitamin D levels in pregnant women in Madrid.

The influence of seasonal variations and gestation on 25(OH)D3 levels was studied in a group of women from Madrid, Spain, at different stages of pregnancy, during March and September. The objective was to observe the incidence of this climate and dietary factors. No variations were found in serum concentration of the metabolite throughout pregnancy in comparison with the controls, in either March or September. 25(OH)D3 values decreased after winter in both groups of women, although mean values were consistently higher than 16 ng/ml.

Calcium balance in the quail (Coturnix coturnix japonica). 1, Influence of sex and diethylstilbestrol.

Young adult male and laying female quail, fed with a diet containing 2.64% Ca and 0.70% P, were used to study nutritive utilization, corporal calcium retention and endogenous excretion, calcemia, laying and properties of the egg (including the shell structure), mineralization of the femur bone, as well as the influence of diethylstilbestrol upon these parameters. The coefficient of nutritive utilization (C.N.U.) in the female was high and logically superior to that of the male, while the corporal retention was quite similar for both sexes. Most of the Ca absorbed (81.8%) and not excreted in urine, went to the egg and only 18.2% remained in the body. The diethylstilbestrol caused a big reduction of the C.N.U. in the female, but not in the male, parallel to an inhibition of laying, and an increase of corporal retention of used calcium. In both sexes the calcemia surprisingly increased, and the calcium level of the femur bone was higher, and even though the cortical osseous zone was slightly wider, the effect of treatment was noticeable, particularly in the medular tissue, which incremented in the female and appeared in the male. When quail were fed a calcium-restricted diet, the endogenous excretion of this mineral was small in the case of the female and significantly smaller in the male. This situation suppressed egg laying and resulted in a clearly decreased bone mineralization. The ingestion of diethylstilbestrol before feeding a diet poor in calcium provoked an increase of the endogenous excretion of calcium in both female and male quail.

Dieldrin, Ca and P balance, and characteristics of the egg in the quail (Coturnix coturnix japonica).

A study was made of the Ca and P balance, Ca and P content in the femur, physical characteristics of the egg, mineral structure of the shell, and the number of eggs in quails treated with dieldrin (20 mg/kg of diet) for 48 days. The diet contained 3.24% Ca and 0.72% P. The Ca and P balance, the bone contents of Ca and P and the calcemia in the males were not changed by the pesticide. In the females, the pesticide decreased the amount of excreted Ca and Ca in the egg, for which reason the coefficient of nutritive utilization (CNU), the coefficient of corporal retention (CCR), and the Ca level in the femur were greater in treated laying quails. The calcemia remained stable, and the balance of P was not significantly modified by the dieldrin. The study of weight, size, and strength of the egg did not reveal any influence of the dieldrin, and egg production fluctuated throughout the test period.

[Isolated ACTH deficiency]. / Déficit aislado de ACTH.

The isolated ACTH deficiency is a scarcely diagnosed disease of heterogeneous nature. Two patients with isolated deficiency of ACTH in whom the initial diagnosis was of primary suprarrenal failure are reported. In the first case this diagnosis was performed after hospital admission for deterioration of the level of consciousness and the development of an acute suprarrenal crisis in the course of nosocomial pneumonia. In the second case the clinical manifestations began as weakness, anorexia, weight loss and lymphocytosis with eosinophilia. In both patients an increase in the thyrotropic hormone was detected leading to suspicion of the existence of associated primary hypothyroidism. Finally, several studies were carried out (basal measurements of cortisol and ACTH, stimulation with continual perfusion of ACTH, insulinic hypoglycemia, global study of adenohypophysary function, ACTH CRF release factor test, computerized tomography of the pituitary region) in both patients leading to the definitive diagnosis of isolated ACTH deficiency of idiopathic cause of possible pituitary origin without the existence of other associated hormonal deficiencies.

[Computerized tomography of the pituitary gland in the diagnosis of prolactinoma: a concordance study]. / La tomografía computadorizada de hipófisis en el diagnóstico de los prolactinomas: estudio de concordancia.

BACKGROUND: The diagnostic capacity of computed tomography (CT) of the pituitary gland in the diagnosis of prolactinomas is difficult to define in terms of specificity and sensitivity since, up to the present, there is no definite diagnostic test for prolactin producing tumors. The aim of this study is to establish the consistency of CT of the hypophysis in the diagnosis of the prolactinomas based on a concordance design. METHODS: In the follow-up study of 48 patients diagnosed as affected of prolactinoma a concordance study was carried out on the blind lecture of 35 pituitary gland CT by two radiologists. RESULTS: The degree of concordance for all the diagnosis (kappa = 0.58) was greater than what might be expected by chance. The degree of concordance was also different for the different diagnosis given by the two radiologists: empty sella turcica, kappa = 0.84 (p less than 0.01); macroprolactinoma, kappa = 0.68 (p less than 0.01); microprolactinoma, kappa = 0.45 (p less than 0.01) and normal sella turcica, kappa = 0.28 (NS). CONCLUSIONS: CT of the hypophysis must be less sensitive (more false negatives) in cases of high prolactin due to microprolactinomas and less specific (more false positives) in cases of high prolactin due to a cause other than pituitary tumor, thereby making it a complementary diagnostic test to clinical evaluation and to prolactin determinations.

[Pregnant rats consuming diets with uncooked and fried olive oil, mineral levels in their offspring and changes in their body storage levels]. / Estudio en ratas gestantes del consumo de dietas con aceite de oliva crudo y frito sobre la mineralización de la camada y la evolución en sus almacenes corporales.

Some parameters relating nutritional utilization of Ca, Mg, Fe and Zn were studied in rats fed with diets including raw and fried fats in order to study more in depth the diet fat/mineral utilization interaction. Wistar rats having initial weights of 176 g were divided into two groups and fed isocaloric diets having 15% fat content as raw olive oil and fried olive oil (from 15 potato fryings), during pregnancy. Weight and dietary intake were controlled and mineral content changes in plasma, liver, spleen and carcass were assessed, as well as litter mineral uptake. Throughout the study, dietary intake of pregnant rats fed raw (R) and fried oil (F), body weight gain and final weight gain were similar. Serum Fe, Zn and Ca levels decreased at a similar rate in both groups. Liver Fe levels decreased more in the F group while spleen Fe decreased more in the R group, these changes started on day 18. Liver Zn levels did not show clear changes but spleen Zn decreased during the last three days of pregnancy. Carcass Ca levels of pregnant rats from the R and F groups did not show any differences at the end of pregnancy. Body weight gain, Ca, Mg, Fe and Zn uptake of the litter were similar in both groups throughout the study. The placentas and the offspring of treated rats showed similar absolute and relative mineralization values. These findings lead us to conclude that fried olive oil retained the same characteristics as raw olive oil regarding mineral utilization.

Degradation, release and bioavailability of 14C DDT and 14C DDE sediment residues to oysters and mussels.

Sediment borne pesticides are one of the major routes of transport of pesticides into the aquatic environment and could affect biota living closely in contact with it. Sediment residues of DDT were found to be easily adsorbed (95.0%) and were released in hard water (8.4%) and seawater (0.1%). DDT and DDE sediment residues were released into sterile and nonsterile brackish water indicating minimal role of micro-organisms. DDT was detected in oyster and in mussel with an average of 46-62% in the shell, 19-31% in the tissues and 19-23% in the fluids. Most of the sediment residues were extractable and released residues in water were in the form of DDT. In the presence oysters, bound was transformed into extractable DDT in sediment after 30 days equivalent to 26% of the total concentration. Most biota residues were extractable and an average of 46% was transformed to DDE. Uptake of residues depend on whether the source of contamination was by direct addition to the water or through sediment residues, if food was given or not, if the source of sediment residues were either aged or freshly treated and if residues were extractable or non-extractable.

[Efficacy of the protein of canned tuna (Thunnus alalunga) in animal growth]. / Eficacia de la proteína de la conserva de bonito (Thunnus alalunga) en el crecimiento animal.

The effect of the manufacturing process on canned tuna (Thunnus alalunga) by the sterilization procedure at 115 degrees C for 60 and 90 minutes on its protein quality was studied. Protein quality was mainly evaluated according to its efficiency for animal growth. Protein from food obtained by the sterilization procedure at 115 degrees C for 60 minutes was similar for animal growth to that from a standard casein-methionine diet. No changes in digestibility and biological values were found between both proteins. Nevertheless, when the sterilization procedure was prolonged up to 90 minutes, the protein suffered modifications. Thus, protein digestibility decreased in spite of the fact that protein digestibility remained unmodified. On the other hand, introduction of the mixed protein into a diet based on flour plus tuna sterilized at 115 degrees C for 90 minutes, was not capable of maintaining the optimum patterns for weight evolution.

Effects of different thermal treatments and storage on the proximate composition and protein quality in canned tuna.

The purpose of this project was to study the modifications in nutrient composition, amino acid content, and protein quality of white tuna preserves after each of the thermal treatments involved in the canning process. Also the influence that a three years storage period at room temperature has on the nutritional quality of canned tuna was studied. The biological assays used for the study of the protein utilization were carried out on Wistar rats, fed on semi-synthetic diets for 12 days varying only the protein source, casein or tuna provided as follows: raw, cooked in brine, steamed, sterilized tuna, and canned tuna stored for three years. The sterilization process and storage time led to a great increase in the lipid content of the canned tuna and to a porcentual decrease in protein, and moisture content. Amino acid composition of canned and cooked tuna did not show great modifications compared to raw tuna. Neither protein digestibility nor biological value of the cooked, canned, and stored tuna showed any deterioration. The protein quality of white tuna meat preserves has been compared with preserves made up of red and white tuna meat.

Variations in tendon stiffness due to diets with different glycotoxins affect mechanical properties in the muscle-tendon unit.

Passive elastic behavior of tendon tissue from rats subjected to different dietary treatments was characterized. For that purpose, twenty-four weanling Wistar rats (41.02 ± 0.16 g) were randomly distributed into four groups. During 88 days each group was fed on different diets: control diet and diets containing advanced glycation end products (AGEs) from glucose-lysine model system, from bread crust and bread dough, respectively. After the trial animals were sacrificed and tendon samples were extracted and tested mechanically to fracture in a uniaxial tensile test machine. A transversely-hyperelastic model was formulated based on stress-strain relationships and its parameters were fit to the experimental data using the Levenberg-Marquardt optimization algorithm. Material parameters were incorporated in a finite element model to study different stress-strain distributions in a muscle-tendon unit. Results show higher strains and stresses in the muscle belly when properties of a stiffer tendon associated with a diet rich in AGEs are included in the model. A real increase in this mechanical response of the tissue could imply possible pain in joint mobility.