Epigenetic Alterations Related to Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is the most common metabolic complication in pregnancy, which affects the future health of both the mother and the newborn. Its pathophysiology involves nutritional, hormonal, immunological, genetic and epigenetic factors. Among the latter, it has been observed that alterations in DNA (deoxyribonucleic acid) methylation patterns and in the levels of certain micro RNAs, whether in placenta or adipose tissue, are related to well-known characteristics of the disease, such as hyperglycemia, insulin resistance, inflammation and excessive placental growth. Furthermore, epigenetic alterations of gestational diabetes mellitus are observable in maternal blood, although their pathophysiological roles are completely unknown. Despite this, it has not been possible to determine the causes of the epigenetic characteristics of GDM, highlighting the need for integral and longitudinal studies. Based on this, this article summarizes the most relevant and recent studies on epigenetic alterations in placenta, adipose tissue and maternal blood associated with GDM in order to provide the reader with a general overview of the subject and indicate future research topics.     

Understanding soluble arsenate removal kinetics by zerovalent iron media

Zerovalent iron filings have been proposed as a filter medium for removing arsenic compounds from potable water supplies. This research investigated the kinetics of arsenate removal from aqueous solutions by zerovalent iron media. Batch experiments were performed to determine the effect of the iron corrosion rate on the rate of As(V) removal. Tafel analyses were used to determine the effect of the As(V) concentration on the rate of iron corrosion in anaerobic solutions. As(V) removal in column reactors packed with iron filings was measured over a 1-year period of continuous operation. Comparison of As(V) removal by freely corroding and cathodically protected iron showed that rates of arsenate removal were dependent on the continuous generation of iron oxide adsorption sites. In addition to adsorption site availability, rates of arsenate removal were also limited by mass transfer associated with As(V) diffusion through iron corrosion products. Steady-state removal rates in the column reactor were up to 10 times faster between the inlet-end and the first sampling port than between the first sampling port and the effluent-end of the column. Faster removal near the influent-end of the column was due to a faster rate of iron oxidation in that region. The presence of 100 microg/L As(V) decreased the iron corrosion rate by up to a factor of 5 compared to a blank electrolyte solution. However, increasing the As(V) concentration from 100 to 20,000 microg/L resulted in no further decrease in the iron corrosion rate. The kinetics of arsenate removal ranged between zeroth- and first-order with respect to the aqueous As(V) concentration. The apparent reaction order was dependent on the availability of adsorption sites and on the aqueous As(V) concentration. X-ray absorption spectroscopy analyses showed the presence of iron metal, magnetite (Fe3O4), an Fe(III) oxide phase, and possibly an Fe(II,III) hydroxide phase in the reacted iron filings. These mixed valent oxide phases are not passivating and permit sustained iron corrosion and continuous generation of new sites for As(V) adsorption.     

Characterization of transthyretin variants in familial transthyretin amyloidosis by mass spectrometric peptide mapping and DNA sequence analysis

Transthyretin (TTR) is a 127-amino acid residue transport protein. In plasma, TTR exists as a tetramer and binds the hormone thyroxine and the retinol-binding protein-vitamin A complex. Amino acid substitutions in TTR are hypothesized to destabilize the tetramer and cause the protein to form intermediates that self-associate into amyloid fibrils. Familial transthyretin amyloidosis (ATTR) is associated with extracellular deposition of wild-type TTR, its variants or fragments as amyloid fibrils in various tissues and organs. A definitive diagnosis of ATTR depends on the detection and identification of TTR variants. Electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS), in combination with trypsin digestion, have been shown to be powerful tools in characterizing TTR variants. Typically, TTR or its tryptic digest is analyzed by MALDI-TOF MS, liquid chromatography ESI MS, or both. Analysis of tryptic digests by MALDI-TOF MS does not provide enough sequence coverage in TTR to identify all possible modifications. To improve sequence coverage, aliquots of immunoprecipitated TTR samples were digested with trypsin, lysyl endopeptidase Lys-C, or endoproteinase Asp-N. Identification of the peptides from each digest by MALDI-TOF MS provided preliminary information about the sites and mass shifts due to amino acid substitutions from genetic mutations and to posttranslational modifications. The location and identity of the modifications in the variant proteins were then confirmed by tandem mass spectrometry, accurate mass measurements, and direct DNA sequence analysis. Using these methodologies, we achieved 100% sequence coverage. The detection of two nonpathologic variants (Thr119Met and Gly6Ser) and four pathologic variants (Phe64Leu, Asp38Ala, Phe44Ser, and previously unreported Trp41Leu) are described as illustrations of this approach.     

Enhanced autocompensating quantum cryptography system

We have improved the hardware and software of our autocompensating system for quantum key distribution by replacing bulk optical components at the end stations with fiber-optic equivalents and implementing software that synchronizes end-station activities, communicates basis choices, corrects errors, and performs privacy amplification over a local area network. The all-fiber-optic arrangement provides stable, efficient, and high-contrast routing of the photons. The low-bit error rate leads to high error-correction efficiency and minimizes data sacrifice during privacy amplification. Characterization measurements made on a number of commercial avalanche photodiodes are presented that highlight the need for improved devices tailored specifically for quantum information applications. A scheme for frequency shifting the photons returning from Alice's station to allow them to be distinguished from backscattered noise photons is also described.     

The firm in the Information Age: organizational responses to technological change in the processed foods sector

The transformation of production processes that occurred acrossa range of manufacturing industries during the Industrial Agegenerated new and more complex requirements for the processof intermediation as well as for the production systems themselves.The development of hierarchical organizations provided firmswith the ability to oversee directly many of these new tasksand to create markets that supported them. In contrast, theadvent of the Information Age has tended not so much to requirethe creation of markets de novo but has rather altered the natureof existing relationships of intermediation in ways that havefacilitated a much wider collection of organizational forms.     

Sex differences in the sensitivity of two self-report depression scales in older depressed inpatients.

Both the Geriatric Depression Scale (J. A. Yesavage et al; see record 1984-02939-001) and the Beck Depression Inventory were less effective in identifying depressed men than women in a sample of 191 geriatric psychiatric inpatients with major unipolar depression. From one quarter to one half of the men were missed cases, depending on the cutoff score used. Separate cutoff scores for older men and women on depression screening instruments may be appropriate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Factorial structure of two health belief measures among older adults.

Confirmatory factor analysis of K. A. Wallston's Multidimensional Health Locus of Control Scale and D. S. Krantz's Health Opinion Survey was conducted using 197 nondiabetic and 171 diabetic older adults. Qualified support was found for the 3-factor structure of the Wallston measure when applied to older adults. The Krantz model provided a less-than-adequate representation of the older sample's data. When the items from these 2 measures were combined, a 4-factor structure was found. Multisample simultaneous factor analyses using LISREL revealed that the factor structures of the Wallston and the Krantz measures fit the diabetic and the nondiabetic samples fairly equivalently. Despite the similarities in factor structures, diabetic individuals reported greater belief in powerful others and less desire for behavioral involvement in the health-care process than did nondiabetics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prediction of infant-father and infant-mother attachment.

The 1st-yr correlations of infant–father and infant–mother attachment were investigated in a longitudinal study of early family development. Mothers and fathers were observed interacting with their 1st-born, 3-mo-old infants. Parents also were interviewed individually at 3 mo child age concerning their time with the infant and their attitudes and reports about the infant and their parental role. Mothers and fathers were seen in the strange situation with their infant at 12 mo. For infants and fathers, security of attachment was predicted from the qualities of interaction at 3 mo, the father's attitudes and reports about the infant and the paternal role, and the father's time with the infant. For infants and mothers, security of attachment was predicted from the qualities of interaction at 3 mo and the mother's time with the infant. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conjugated linoleic acid modulation of phorbol ester-induced events in murine keratinocytes

Recent work in our lab has shown that the chemoprotective fatty acid, conjugated linoleic acid (CLA), inhibits phorbol ester skin tumor promotion in mice. Because little is known about the deposition of CLA into tissues as well as its biological activity, this study compared the incorporation and biological activity of CLA to linoleic acid (LA; 18:2, c9, c12) and arachidonic acid (AA; 20:4 c5, c8, c11, c14) in cultured keratinocytes. When keratinocytes (HEL-30) were grown in media containing ¹⁴C-CLA for various periods, more than 50% of the ¹⁴C-CLA was incorporated into cellular lipids by 9 h. The distribution of CLA in phospholipid classes was similar to LA. Approximately 50% of ¹⁴C-LA and ¹⁴C-CLA were incorporated into phosphatidylcholine (PC), while the remainder was taken up by phosphatidylethanolamine (PE) and phosphatidyl-serine/phosphatidylinositol (PS/PI). In contrast, ¹⁴C-AA was more equitably distributed into PC, PE, or PS/PI (27, 30, or 38%, respectively). When keratinocytes were prelabeled with radiolabeled fatty acids, phorbol ester-induced release of ¹⁴C-CLA was 1.5 times higher than ¹⁴C-LA and ¹⁴C-AA. However, ¹⁴C-prostaglandin E (PGE) release in ¹⁴C-CLA prelabeled cultures was 6 and 13 times lower than cultures treated with ¹⁴C-LA and ¹⁴C-AA, respectively. Moreover, the ability of nonradiolabeled CLA to support ornithine decarboxylase activity, a hallmark event of tumor promotion, was significantly lower than in LA- and AA-treated cultures. These studies suggest that CLA inhibits skin tumor promotion, in part, through a PGE-de-pendent mechanism.