Characterization of aerosols containing Zn, Pb, and Cl from an industrial region of Mexico City

Recent ice core measurements show lead concentrations increasing since 1970, suggesting new nonautomobile-related sources of Pb are becoming important worldwide (1). Developing a full understanding of the major sources of Pb and other metals is critical to controlling these emissions. During the March, 2006 MILAGRO campaign, single particle measurements in Mexico City revealed the frequent appearance of particles internally mixed with Zn, Pb, Cl, and P. Pb concentrations were as high as 1.14 microg/m3 in PM10 and 0.76 microg/m3 in PM2.5. Real time measurements were used to select time periods of interest to perform offline analysis to obtain detailed aerosol speciation. Many Zn-rich particles had needle-like structures and were found to be composed of ZnO and/or Zn(NO3)2 x 6H2O. The internally mixed Pb-Zn-Cl particles represented as much as 73% of the fine mode particles (by number) in the morning hours between 2-5 am. The Pb-Zn-Cl particles were primarily in the submicrometer size range and typically mixed with elemental carbon suggesting a combustion source. The unique single particle chemical associations measured in this study closely match signatures indicative of waste incineration. Our findings also show these industrial emissions play an important role in heterogeneous processing of NO(y) species. Primary emissions of metal and sodium chloride particles emitted by the same source underwent heterogeneous transformations into nitrate particles as soon as photochemical production of nitric acid began each day at approximately 7 am.     

Phenolic acids and flavonoids profiles of extracts from edible wild fruits and their antioxidant properties

In this study, the total phenolic, total flavonoids, phenolic compounds, the mineral content, and antioxidant activity of fruit extracts of seven wild species (Crataegus monogyna Jacq., Prunus spinosa L., Rosa canina L., Hippophaë rhamnoides L., Rubus fruticosus L., Prunus padus, Cornus mas L.) were investigated. The results indicated significant differences (p < 0.05) in the total phenolics and total flavonoids content, between the seven analyzed species. These ranged from 184.69 to 727.29 mg GAE/100 g FW and 17.27 to –165.55 mg QE/100 g FW, respectively. The antioxidant activity found in fruits was not directly affected by the total phenolic content (TPC). This activity was linked to a larger extent to the type of individual phenolic compounds and to a lesser extent to the TPC, because fruits with higher TPC have not always presented the highest values of antioxidant activity. HPLC analysis of methanolic extract showed the presence of phenolic acids (i.e. gallic, vanillic, chlorogenic, caffeic, syringic, p-coumaric, ferulic, sinapic, salycilic, elagic, and trans-cinnamic) and flavonoids (i.e. catechin, epicatechin, rutin, myricetin, and quercetin). Significant differences (p < 0.05) were observed in each individual mineral between fruits from wild flora. The fruits tissues of wild species turned out to be a good source of calcium (Ca), magnesium (Mg), sodium (Na), iron (Fe), manganese (Mn), copper (Cu), chromium (Cr), zinc (Zn), and boron (B). The results demonstrated that wild species possessed great potential for food production as sources of bioactive compounds such as phenolic compounds and minerals, for food supplements or functional foods.     

The Expression of Connexin 37, 40, 43, 45 and Pannexin 1 in the Early Human Retina and Choroid Development and Tumorigenesis

The expression pattern of Connexins (Cx) 37, 40, 43, 45 and Pannexin 1 (Pnx1) was analyzed immunohistochemically, as well as semi-quantitatively and quantitatively in histological sections of developing 8th- to 12th-week human eyes and postnatal healthy eye, in retinoblastoma and different uveal melanomas. Expressions of both Cx37 and Cx43 increased during development but diminished in the postnatal period, being higher in the retina than in the choroid. Cx37 was highly expressed in the choroid of retinoblastoma, and Cx43 in epitheloid melanoma, while they were both increasingly expressed in mixoid melanoma. In contrast, mild retinal Cx40 expression during development increased to strong in postnatal period, while it was significantly higher in the choroid of mixoid melanoma. Cx45 showed significantly higher expression in the developing retina compared to other samples, while it became low postnatally and in all types of melanoma. Pnx1 was increasingly expressed in developing choroid but became lower in the postnatal eye. It was strongly expressed in epithelial and spindle melanoma, and particularly in retinoblastoma. Our results indicate importance of Cx37 and Cx40 expression in normal and pathological vascularization, and Cx43 expression in inflammatory response. Whereas Cx45 is involved in early stages of eye development, Pnx1might influence cell metabolism. Additionally, Cx43 might be a potential biomarker of tumor prognosis.     

Kappa-Opioid Receptor Blockade Ameliorates Obesity Caused by Estrogen Withdrawal via Promotion of Energy Expenditure through mTOR Pathway

Weight gain is a hallmark of decreased estradiol (E2) levels because of menopause or following surgical ovariectomy (OVX) at younger ages. Of note, this weight gain tends to be around the abdomen, which is frequently associated with impaired metabolic homeostasis and greater cardiovascular risk in both rodents and humans. However, the molecular underpinnings and the neuronal basis for these effects remain to be elucidated. The aim of this study is to elucidate whether the kappa-opioid receptor (k-OR) system is involved in mediating body weight changes associated with E2 withdrawal. Here, we document that body weight gain induced by OVX occurs, at least partially, in a k-OR dependent manner, by modulation of energy expenditure independently of food intake as assessed in Oprk1−/−global KO mice. These effects were also observed following central pharmacological blockade of the k-OR system using the k-OR-selective antagonist PF-04455242 in wild type mice, in which we also observed a decrease in OVX-induced weight gain associated with increased UCP1 positive immunostaining in brown adipose tissue (BAT) and browning of white adipose tissue (WAT). Remarkably, the hypothalamic mTOR pathway plays an important role in regulating weight gain and adiposity in OVX mice. These findings will help to define new therapies to manage metabolic disorders associated with low/null E2 levels based on the modulation of central k-OR signaling.     

The Significance of Epidermal Growth Factor in Noninvasively Obtained Amniotic Fluid Predicting Respiratory Outcomes of Preterm Neonates

Preterm premature rupture of membranes (PPROM) interrupts normal lung development, resulting in neonatal respiratory morbidity. Although post-PPROM risks have been researched, only a few studies have investigated noninvasively obtained amniotic fluid (AF) to predict neonatal outcomes. In this study, we aimed to determine whether epidermal growth factor (EGF) in vaginally-collected AF is a significant predictor of neonatal respiratory outcomes after PPROM. We analyzed EGF in vaginally-obtained AF from 145 women with PPROM at 22–34 weeks of gestation. The following neonatal outcomes were included: respiratory distress syndrome, surfactant need, duration and type of respiratory support, and bronchopulmonary dysplasia. We found that EGF concentration was associated with gestational age, and its medians were lower in neonates with respiratory morbidities than unaffected ones. EGF concentrations gradually declined, the lowest being in the most clinically ill patients. EGF < 35 pg/mL significantly predicted the odds of severe respiratory outcomes. EGF in noninvasively collected AF may be a reliable predictor for respiratory outcomes of preterm neonates with PPROM before 34 weeks of gestation. The results of our study may have implications for further research both in noninvasive amniotic fluid analysis and the management of patients after PPROM.     

Gold-standard and improved framework for sperm head segmentation

Semen analysis is the first step in the evaluation of an infertile couple. Within this process, an accurate and objective morphological analysis becomes more critical as it is based on the correct detection and segmentation of human sperm components. In this paper, we present an improved two-stage framework for detection and segmentation of human sperm head characteristics (including acrosome and nucleus) that uses three different color spaces. The first stage detects regions of interest that define sperm heads, using k-means, then candidate heads are refined using mathematical morphology. In the second stage, we work on each region of interest to segment accurately the sperm head as well as nucleus and acrosome, using clustering and histogram statistical analysis techniques. Our proposal is also characterized by being fully automatic, where a user intervention is not required. Our experimental evaluation shows that our proposed method outperforms the state-of-the-art. This is supported by the results of different evaluation metrics. In addition, we propose a gold-standard built with the cooperation of a referent expert in the field, aiming to compare methods for detecting and segmenting sperm cells. Our results achieve notable improvement getting above 98% in the sperm head detection process at the expense of having significantly fewer false positives obtained by the state-of-the-art method. Our results also show an accurate head, acrosome and nucleus segmentation achieving over 80% overlapping against hand-segmented gold-standard. Our method achieves higher Dice coefficient, lower Hausdorff distance and less dispersion with respect to the results achieved by the state-of-the-art method.     

INVEX: Investment Advisory Expert System

Abstract: Capital investment is a very important business decision, because it is largely irreversible and usually long-term. We believe that the use of expert systems as a decision aid for interactive investment decision-making offers several advantages to an unassisted human decision-maker, or even to the human/conventional-DSS combination. For example, the expert system could capture valuable information about so called 'hard data', and about the attitude towards some drastic changes in the environment, that are not easy to include in any quantitative method. However, if one expert can play a very important role in the decision-making process, perhaps different experts can be even more valuable, bringing different approaches and somewhat different sets of information to a decision-making situation. Our multiparadigm blackboard framework, called BEST (Blackboard-based Expert Systems Toolkit), allows its user to combine knowledge coming from different experts, and to use different methods/paradigms to capture that knowledge, according to the type of partial problem at hand where each knowledge source is a single paradigm program. In investment decision-making, judgmental investment ranking and selection from expert economists, embedded in a rule-based knowledge source, might be combined with decisions from operational research methods (embedded in a knowledge source that fully respects multicriteria optimization paradigm) and from risk analysis method (embedded in a conventional, procedural knowledge source). When the decisions being combined come from different types of knowledge sources, redundancy is likely to be reduced and the combined decision is likely to be more objective.     

Dissociation and Unfolding of Sulfhydryl Oxidase in Solutions of Guanidinium Chloride

Sulfhydryl oxidase was dissociated completely in 5 M guanidinium chloride as indicated by light scattering molecular weight studies giving masses of 80,000 to 90,000 daltons. Concentrations of guanidinium chloride above 2 M resulted in loss of enzymatic activity and caused extensive unfolding of the enzyme as shown by fluorescence measurements. Replacement of the denaturant with physiological buffers restored native fluorescence characteristics, but the enzyme remained partially dissociated, with a molecular weight of 300,000 to 360,000, and enzymatic activity was not restored.