A Critical Review about Human Exposure to Polychlorinated Dibenzo-p-Dioxins (PCDDs), Polychlorinated Dibenzofurans (PCDFs) and Polychlorinated Biphenyls (PCBs) through Foods.

Dioxins include polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and part of polychlorinated biphenyls (PCBs). Only the compounds that are chlorinated at the 2,3,7, and 8 positions have characteristic dioxin toxicity. PCDDs, PCDFs and PCBs accumulate in the food chain due to their high lipophilicity, high stability, and low vapor pressure. They are not metabolized easily; however their hydroxylated metabolites are detected in feces. They cause a wide range of endocrine disrupting effects in experimental animals, wildlife, and humans. Endocrine related effects of PCDDs, PCDFs and PCBs on thyroid hormones, neurodevelopment and reproductive development were referenced. In addition, some studies of contamination of foods, bioaccumulation, dietary exposure assessment, as well as challenges of scientific research in these compounds were reviewed.

Influence of dissolved oxygen concentration on the start-up of the anammox-based process: ELAN®.

The anammox-based process ELAN® was started-up in two different sequencing batch reactor (SBR) pilot plant reactors treating municipal anaerobic digester supernatant. The main difference in the operation of both reactors was the dissolved oxygen (DO) concentration in the bulk liquid. SBR-1 was started at a DO value of 0.4 mg O2/L whereas SBR-2 was started at DO values of 3.0 mg O2/L. Despite both reactors working at a nitrogen removal rate of around 0.6 g N/(L d), in SBR-1, granules represented only a small fraction of the total biomass and reached a diameter of 1.1 mm after 7 months of operation, while in SBR-2 the biomass was mainly composed of granules with an average diameter of 3.2 mm after the same operational period. Oxygen microelectrode profiling revealed that granules from SBR-2 where only fully penetrated by oxygen with DO concentrations of 8 mg O2/L while granules from SBR-1 were already oxygen penetrated at DO concentrations of 1 mg O2/L. In this way granules from SBR-2 performed better due to the thick layer of ammonia oxidizing bacteria, which accounted for up to 20% of all the microbial populations, which protected the anammox bacteria from non-suitable liquid media conditions.

Most regions of mouse epididymis are able to phagocytose immature germ cells.

The role of the epididymis as a quality control organ in preventing infertile gametes entering the ejaculate has been extensively explored, and it has been suggested that a specific region of mammalian epididymis is able to phagocytose abnormal germ cells. This study examines whether the epithelium of certain zones of the mouse epididymis can act as a selection barrier by removing immature germ cells from the lumen by phagocytosis. To detect the presence of immature germ cells in the epididymis, we generated transgenic mice expressing enhanced green fluorescent protein under the deleted in azoospermia-like (mDazl) promoter to easily identify immature germ cells under fluorescence microscopy. Using this technique, we observed that during the first stage of spermatogenesis in prepuberal mice, a wave of immature germ cells is released into the epididymis and that the immature epididymis is not able to react to this abnormal situation. By contrast, when immature germ cells were artificially released into the epididymis in adult mice, a phagocytic response was observed. Phagosomes appeared inside principal cells of the epididymal epithelium and were observed to contain immature germ cells at different degradation stages in different zones of the epididymis, following the main wave of immature germ cells. In this paper, we describe how the epididymal epithelium controls sperm quality by clearing immature germ cells in response to their artificially induced massive shedding into the epididymal lumen. Our observations indicate that this phenomenon is not restricted to a given epididymis region and that phagocytic capacity is gradually acquired during epididymal development.

Treatment with cholesterol-loaded methyl-ß-cyclodextrin increased the cholesterol in rabbit oocytes, but did not improve developmental competence of cryopreserved oocytes.

Membrane cholesterol:phospholipids ratio is an important determinant of cell chilling sensitivity. At low temperatures, major membrane destabilisation occurs when the membrane undergoes a phase transition. To increase membrane fluidity and stability during cooling and thus increase oocyte cryoresistance, cholesterol has been added to the plasma membrane. This study was conducted to determine if cholesterol could be incorporated into rabbit oocytes by incubation with cholesterol-loaded methyl-ß-cyclodextrin (CLC) and if added cholesterol could improve the developmental ability of cryopreserved oocytes after parthenogenetic activation or intracytoplasmic sperm injection. Fresh, frozen and vitrified oocytes incubated with CLC containing 20% NBD-labelled cholesterol (NBD-CLC) were evaluated using confocal microscopy. Fluorescence intensity was higher in fresh oocytes than in cryopreserved ones. Pre-treating rabbit oocytes with 1mg of NBD-CLC/mL did not improve cleavage and developmental rates after cryopreservation. Results showed that treatment with CLC increased the cytoplasmic cholesterol content, but did not improve cleavage rate and developmental competence of cryopreserved oocytes.

Sex-specific embryonic origin of postnatal phenotypic variability.

Preimplantation developmental plasticity has evolved in order to offer the best chances of survival under changing environments. Conversely, environmental conditions experienced in early life can dramatically influence neonatal and adult biology, which may result in detrimental long-term effects. Several studies have shown that small size at birth, which is associated with a greater risk of metabolic syndrome, is largely determined before the formation of the blastocysts because 70%-80% of variation in bodyweight at birth has neither a genetic nor environmental component. In addition, it has been reported that adult bodyweight is programmed by energy-dependent process during the pronuclear stage in the mouse. Although the early embryo has a high developmental plasticity and adapts and survives to adverse environmental conditions, this adaptation may have adverse consequences and there is strong evidence that in vitro culture can be a risk factor for abnormal fetal outcomes in animals systems, with growing data suggesting that a similar link may be apparent for humans. In this context, male and female preimplantation embryos display sex-specific transcriptional and epigenetic regulation, which, in the case of bovine blastocysts, expands to one-third of the transcripts detected through microarray analysis. This sex-specific bias may convert the otherwise buffered stochastic variability in developmental networks in a sex-determined response to the environmental hazard. It has been widely reported that environment can affect preimplantation development in a sex-specific manner, resulting in either a short-term sex ratio adjustment or in long-term sex-specific effects on adult health. The present article reviews current knowledge about the natural phenotypic variation caused by epigenetic mechanisms and the mechanisms modulating sex-specific changes in phenotype during early embryo development resulting in sex ratio adjustments or detrimental sex-specific consequences for adult health. Understanding the natural embryo sexual dimorphism for programming trajectories will help understand the early mechanisms of response to environmental insults.

Removal of heavy metals from acid mining effluents by hydrolyzed olive cake.

The present study aims to solve two major challenges of the current society. On the one hand, it investigated the heavy metal removal from mining wastewater. On the other hand, it proposed an alternative use for olive cake. Firstly, a physic-chemical characterization of real wastewater and hydrolyzed olive cake was carried out. Secondly, a study of the affinity of the material for the different metals (chromium, manganese, copper, zinc, nickel and lead) was performed. The hydrolyzed olive cake showed a low content in ash (3.08%) and in water-soluble compounds (2.80%). The material presented the highest retention capacity for the lead (41.54 mg/g) and the lowest for the manganese (3.57 mg/g). After that, biosorption experiments in fixed-bed column were carried out using mining real water. In order to improve the biosorption capacity, the water pH was raised up to 6. The results were quite satisfactory with respect to others similar studies.

Developmental consequences of sexual dimorphism during pre-implantation embryonic development.

Abnormalities of development potential arising from pre-implantation environment are not limited to in vitro culture (IVC) (for, i.e. in ruminants the large offspring syndrome produced by IVC), they may also be consequence of specific stress conditions experienced in vivo, like maternal diet, toxins, etc. A complex group of mechanisms (gene expression, epigenetic, metabolic, etc.) may operate to link early embryo environment with future health. Furthermore, during the pre-implantation period, in vitro produced male embryos have a higher metabolic rate, they grow faster than females, and they also have differential gene transcription of genes located in the Y-, X-, or in autosomal-chromosomes. As a consequence of these differences embryos may be affected differentially by natural or artificial environmental conditions, depending on their gender. It has been suggested that under some stress conditions male embryos are more vulnerable than females; however the biological fragility of male embryos is poorly understood. Evidences suggest that epigenetic differences produced by the presence of one or two X-chromosomes are the principal cause of the male and female pre-implantation differences, and we put forward the possible role of these early sex differences to control sex ratio of the offspring under different environmental conditions in Nature. By following the differences between male and female early embryos not only may be possible to manipulate sex ratio in farm animals, we can also gain further insight into aspects of early embryo development, X inactivation, and epigenetic and genetic processes related with early development that may have a long-term effect on the offspring.

[Degree of fulfillment of the objectives of metabolic control and cardiovascular risk factors in patients with type 2 diabetes in an area of primary attention]. / Grado de cumplimiento de los objetivos de control metabólico y de los factores de riesgo cardiovascular en pacientes diabéticos tipo 2 en un área de Atención Primaria.

UNLABELLED: Diabetes mellitus type is one of de most important health problem in the world, due to its high prevalence and morbidity and its relation with several cardiovascular risk factors. That s why a global action, aimed to prevent these vascular syndromes, is needed. OBJECTIVE: the goal of this study is to detect and determine how cardiovascular risk factor are controlled in diabetic type 2 patients, according to the date supplied by several international organization that have been studied at a Health Centre of Valladolid. METHODS: It is a descriptive cross-sectional study to evaluate the control of several cardiovascular risk factors in diabetic patients according to the different established criteria. The sample is formed by 74 adult patients (41 men and 33 women), included in the Diabetes Mellitus Program at Health Centre of Rondilla 2, at East Area of Primary Care of Valladolid, in the programmed consultation of cardiovascular risk factors control. RESULTS AND CONCLUSION: I has been observed that the majority of these cardiovascular risk factors are not well controlled. In this way, stringent measures of control should be considered in order to prevent the cardiovascular complications related to them.

Automatic segmentation of histological structures in mammary gland tissue sections.

Real-time three-dimensional (3-D) reconstruction of epithelial structures in human mammary gland tissue blocks mapped with selected markers would be an extremely helpful tool for diagnosing breast cancer and planning treatment. Besides its clear clinical application, this tool could also shed a great deal of light on the molecular basis of the initiation and progression of breast cancer. We present a framework for real-time segmentation of epithelial structures in two-dimensional (2-D) images of sections of normal and neoplastic mammary gland tissue blocks. Complete 3-D rendering of the tissue can then be done by surface rendering of the structures detected in consecutive sections of the blocks. Paraffin-embedded or frozen tissue blocks are first sliced and sections are stained with hematoxylin and eosin. The sections are then imaged using conventional bright-field microscopy and their background corrected using a phantom image. We then use the fast-marching algorithm to roughly extract the contours of the different morphological structures in the images. The result is then refined with the level-set method, which converges to an accurate (subpixel) solution for the segmentation problem. Finally, our system stacks together the 2-D results obtained in order to reconstruct a 3-D representation of the entire tissue block under study. Our method is illustrated with results from the segmentation of human and mouse mammary gland tissue samples.

Effect of verapamil on home self-measurement of blood pressure and heart rate by hypertensive patients. Verapamil-Frequency Research Group.

BACKGROUND: Achievement of a controlled blood pressure and improvement of cardiovascular risk profile are the mainstays of therapy for hypertension. OBJECTIVE: To assess the responses of heart rate and blood pressure in hypertensive patients to 240 mg/day sustained release verapamil. METHODS: We assessed the effect of 240 mg/day sustained released verapamil on blood pressure and heart rate, measured in the office and at home, in 1395 hypertensive outpatients with mild-to-moderate hypertension, who were using an Omron HEM 705 CP automatic device for self-measurement. The period of observation was 3 months. RESULTS: Blood pressure decreased both in the medical office and at the patient's home, the measurements obtained at home being lower than those found in the office. Heart rate decreased in a significant and particular way. The decrease was greatest among those patients with histories of myocardial infarction and among relatively young patients, who exhibit a tendency towards higher than normal baseline heart rates. Overall, there was a shift of the heart-rate curve towards more controlled levels clustered around heart rates between 65 and 75 beats/min. Home self-measurement showed that the data gathered by the patients at home are reliable and that, when cut-off values of 140/90 mm Hg for blood pressure are used, the percentage of patients with controlled blood pressures is 62%, whereas the percentage obtained in the medical office by the physician is 56%. If cut-off values of 135/85 mm Hg are considered for self-measurements at home, according to the VI JNC recommendations, the percentage of patients with controlled blood pressures is 25.4%.

[The effect of trandolapril, in monotherapy and associated with verapamil, on arterial pressure, albuminuria, and metabolic control in hypertensive patients with type 2 diabetes and albuminuria]. / Efecto del trandolapril, en monoterapia y asociado con verapamil, sobre la presión arterial, albuminuria y control metabólico en pacientes hipertensos con diabetes tipo 2 y albuminuria.

The aim of this study was to analyse the effect of the ACE-1, Trandolapril, alone or with Verapamil on blood pressure, albuminuria and metabolic profile in type 2 diabetic patients with hypertension and albuminuria. It was an open multicenter, consecutive and prospective study conducted in 281 patients. There was a four-week wash-out period of antihypertensive drugs, after which we carried out a measurement over a 24-h period of the urinary excretion of albumina (UEA). Blood pressure was recorded after at least 5 minutes of rest in the sitting position at 1 to 3 minute intervals with a mercury sphygmomanometer in good condition. Average BP was obtained from three consecutive readings. Within treatment changes were analysed using descriptive statistics and t-tests on the change from baseline. Analysis of variance, chi-square and Mc Nemar tests were also used. If after 8 weeks of treatment with Trandolapril 2 mg o.q.d. the patients were non-responders (mean blood pressure reduction of 5 mmHg or less) or their blood pressure remained uncontrolled (blood pressure > or = 140/90 mmHg), Verapamil 180 mg o.q.d. was added. Two hundred and thirty patients completed the 12 weeks study. Population included 157 (55.9%) males with an average of 61.7 +/- 9.2 years. Baseline measurements were systolic 165.4 +/- 14.6 and diastolic 94.8 +/- 8.5 mmHg blood pressures, fasting glucose 162.7 +/- 43.9 mg/dL, glycosylated hemoglobin (HbAlc) 6.8 +/- 1.2%, and albuminuria 520.9 +/- 602 mg/day. UEA fell significantly (p < 0.001) after treatment to 177.9 +/- 24.3 mg/day (CI 95%, 129.9 to 225.8). The percent reduction reached 29.6%. Albuminuria was lower than 30 mg/day in 47 patients. Blood pressure was completely controlled in 125 (54%) patients. Glucemia fell significantly (p < 0.001) to 153.2 +/- 42.7 mg/dL, and the HbAlc to 6.5 +/- 1.3% (p = 0.012). In summary, in those diabetic type 2 patients with arterial hypertension and proteinuria, Trandolapril alone or associated with Verapamil significant lowered albuminuria and blood pressure facilitated the control or their metabolic profile.

[Effect of antihypertensive combinations on arterial pressure, albuminuria, and glycemic control in patients with type II diabetic nephropathy: a randomized study]. / Efecto de dos combinaciones antihipertensivas sobre la presión arterial, albuminuria y control glucémico en pacientes con nefropatía diabética tipo 2: un estudio aleatorizado.

Type II diabetic patients with albuminuria are at high risk for cardiovascular complications; the intense antihypertensive treatment required often involves using drug combinations. The aim of the present study was to compare the effect of two different, renin-angiotensin blocking combinations, on blood pressure (BP), albuminuria and glycemic control. Its design was prospective, randomised, controlled, of parallel branches, and performed in one Endocrinology Department, in Spain. 77 type-II diabetic patients, with stable albuminuria (30-1,000 mg/day) were included. After a pre-inclusion time of 2 weeks, patients were randomised to verapamil SR/trandolapril 180/2 (VT) or losartan/hydrochlorothiazide (LH) 20/12.5 mg/day. Duration of treatment was 1 year. The evaluated parameters were changes in blood pressure, urinary albumin excretion for 24 hours, glycated hemoglobin and plasmatic urea. Overall BP significantly decreased from 161.6 +/- 18.7/83.6 +/- 10.2 mmHg to 137.2 +/- 15.7/70.9 +/- 8.3 mmHg (p < 0.0005). Values, by treatment, were: For VT, 164.3 +/- 18.5/87.2 +/- 10.7 mmHg at baseline and 135.0 +/- 15.1/71.3 +/- 8.4 mmHg at conclusion. For LH, 158.8 +/- 17.4/80.1 +/- 8.4 mmHg at baseline and 139.3 +/- 16.1/70.5 +/- 8.2 mmHg at conclusion. Albuminuria significantly decreased from 308.2 +/- 544.7 mg/day to 198.0 +/- 285.3 mg/day. Both parameters showed no significant difference between treatments. Glycated hemoglobin decreased from 7.59 +/- 1.3% to 7.14 +/- 1.2% in the VT group, and from 7.96 +/- 1.29% to 7.84 +/- 1.62% in the LH group (ANOVA, p = 0.022). Changes adjusted from baseline values showed a trend to the difference between both treatments (p = 0.092). Plasmatic urea increased from 39.8 +/- 12.7 to 40.5 +/- 11.1 mg/dL in the TV group and from 43.4 +/- 12.0 mg/dL to 52.4 +/- 19.4 mg/dL in the LH group (ANOVA, p = 0.028). In conclusion, both treatments reduce blood pressure and albuminuria in a similar way in type II diabetic patients. The verapamil/trandolapril combination contributes to a better carbohydrate metabolism than losartan/hydroclorothiazide.

[The TPN of newborn infants: the rationalization of the calculations and of the prescription]. / NPT de neonatos: racionalización de los cálculos y de la presecripción.

We try to simplify the calculus of TPN necessities in newborns adjusting the most common bibliography tabulated values to mathematical equations. Values are transformed into factors: Fn (g of N/Kg of weight), Fk (no protein Kcal/g of N), Fg (glucose Kcal/total Kcal) and Fv (volume/total Kcal) that can be correlated with the analytical state of patient, weight and nutrition day. Once the functions were established we automated calculations using a spreadsheet program that simplifies and make easier the TPN elaboration.

Decontamination solutions for polychlorinated biphenyls (PCBs) in raw fish oils from environmentally contaminated sea fishes.

Fish oil has been identified as one of the most important contributors to the levels of polychlorinated biphenyls (PCBs) in food and feed products. In this study, PCB adsorption from fish oil onto activated carbon (AC), other sustainable adsorbents (mussel shell and wood waste ashes) and organic solvent such as ethanol were compared and optimized. Regarding to adsorbents, PCBs were extracted from fish oil by a 2.0% adsorbent material dose, during 6.0 h at 25 °C. Solvent extraction was carried out using 2 × 5.0 mL ethanol by manually stirring for 3.0 min, and then by Ultrasound-Assisted Solvent Extraction (UASE) for 5.0 min. The results showed that removal rates obtained by using adsorbent materials ranged from 0.0 to 10% for marker PCBs, from 0.0 to 37% for mono-ortho-PCBs, from 0.0 to 74% for PCB11 and from 0.0 to 95% for non-ortho-PCBs. Regarding to solvent extraction, ethanol was used by manually stirring and then by Ultrasound-Assisted Solvent Extraction (UASE). The samples were then centrifuged (2000 rpm/10 min) and the alcoholic phase was removed. With this method, removal efficiencies were much better (85-116%); nevertheless, high eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) removal rates (70-78 and 71-79%, respectively) were detected. We can conclude that adsorption with adsorbents depends on the geometry of PCB congeners, as well as both type of adsorption material and their origin, and that several sorption cycles are needed. Adsorption with ethanol could be the most effective methodology but nutritional quality was impaired, what makes necessary to look for other not so polar removal solvents.

Differential effects of culture and nuclear transfer on relative transcript levels of genes with key roles during preimplantation.

It is well known that the preimplantation culture environment to which embryos are exposed influences the expression of developmentally important genes. Recently, it has been reported that MEMalpha, a culture medium commonly used for somatic cells, allows high rates of preimplantation development and development to term of mouse somatic cell nuclear transfer (SCNT) embryos. The objective of this study was to compare the differential effects of this medium and of the nuclear transfer procedure on the relative mRNA abundance of several genes with key roles during preimplantation. The relative mRNA levels of nine genes (Glut 1, Glut 5, G6PDH, Bax, Survivin, Gpx 1, Oct4, mTert and IGF2bp1) were quantified at blastocyst stage on cumulus cell cloned embryos cultured in MEMalpha, as well as on in vivo cultured and MEMalpha cultured controls. Only three of the nine transcripts analysed (Glut 5, Gpx 1 and Igf2bp1) were significantly down-regulated at blastocyst stage in in vitro produced controls. However, most genes analysed in our MEMalpha cultured cloned embryos showed altered transcription levels. Interestingly, between cloned and in vitro produced controls only the transcription levels measured for Glut 1 were significantly different. This result suggests that Glut 1 may be a good marker for embryo quality after cumulus cell nuclear transfer.

Differential sensitivity of male and female mouse embryos to oxidative induced heat-stress is mediated by glucose-6-phosphate dehydrogenase gene expression.

During the preimplantation period, in vitro cultured males have a higher metabolic rate, different gene expression, and grow faster than females. It has been suggested that under some stress conditions male embryos are more vulnerable than females; however, the biological fragility of male embryos is little understood. Since many forms of stress result in the overproduction of cellular reactive oxygen species (ROS), we addressed the hypothesis that the connection between female advantage during early developmental stages and heat stress involves ROS and differential gene expression of G6PD, an X-linked gene related to oxidative stress. We have found that after compaction, female heat-stressed embryos have less relative amounts of H2O2 than males, and female embryos survive better than males under in vivo or in vitro heat stress situations. In addition, in vitro produced female embryos grow slower than male embryos, have differential mRNA transcription of G6PD and also of some genes situated on autosomal-chromosomes (Sox, Bax, and Oct-4). Moreover, by inhibiting G6PD, all differences generated by oxidative stress between male and female embryos disappear. For the first time, we provide an experimental demonstration of a mechanism that explains why following exposure to heat stress-induced ROS, female preimplantation embryos are more resistant than males.

Automatic registration of serial mammary gland sections.

We present two methods for automatic registration of microscope images of consecutive tissue sections. They represent two possibilities for the first step in the 3-D reconstruction of histological structures from serially sectioned tissue blocks. The goal is to accurately align the sections in order to place every relevant shape contained in each image in front of its corresponding shape in the following section before detecting the structures of interest and rendering them in 3D. This is accomplished by finding the best rigid body transformation (translation and rotation) of the image being registered by maximizing a matching function based on the image content correlation. The first method makes use of the entire image information, whereas the second one uses only the information located at specific sites, as determined by the segmentation of the most relevant tissue structures. To reduce computing time, we use a multiresolution pyramidal approach that reaches the best registration transformation in increasing resolution steps. In each step, a subsampled version of the images is used. Both methods rely on a binary image which is a thresholded version of the Sobel gradients of the image (first method) or a set of boundaries manually or automatically obtained that define important histological structures of the sections. Then distance-transform of the binary image is computed. A proximity function is then calculated between the distance image of the image being registered and that of the reference image. The transformation providing a maximum of the proximity function is then used as the starting point of the following step. This is iterated until the registration error lies below a minimum value.