Search

ABSTRACT Recently, there has been considerable debate regarding the appropriate amount of iron fortification for commercial infant formula. Globally, there is considerable variation in formula iron content, from 4 to 12 mg iron/L. However, how much fortification is necessary is unclear. Human milk is low in iron (0.2-0.5 mg/L), with the majority of infant iron stores accumulated during gestation. Over the first few months of life, these stores are depleted in breastfeeding infants. This decline has been previously largely perceived as pathological; it may be instead an adaptive mechanism to minimize iron availability to pathogens coinciding with complementary feeding. Many of the pathogens involved in infantile illnesses require iron for growth and replication. By reducing infant iron stores at the onset of complementary feeding, infant physiology may limit its availability to these pathogens, decreasing frequency and severity of infection. This adaptive strategy for iron regulation during development is undermined by the excess dietary iron commonly found in infant formula, both the iron that can be incorporated into the body and the excess iron that will be excreted in feces. Some of this excess iron may promote the growth of pathogenic, iron requiring bacteria disrupting synergistic microflora commonly found in breastfed infants. Evolutionarily, mothers who produced milk with less iron and infants who had decreased iron stores at the time of weaning may have been more likely to survive the transition to solid foods by having limited iron available for pathogens. Contemporary fortification practices may undermine these adaptive mechanisms and increase infant illness risk. Am. J. Hum. Biol. 26:10-17, 2014. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

This study investigated Hg uptake from soil into garden crops to help assess the significance of human consumption of crops as a potential route of exposure to Hg. Locations for both a floodplain and a control garden were identified within the Augusta Forestry Center near Crimora, VA, USA, which is about 16 river-km downstream from the city of Waynesboro, along the South River. The floodplain garden had measured soil Hg concentrations ranging from 4.2 to 78 mg Hg kg−1dry weight basis in the surface to 15-cm deep layer. A total of 139 samples from the floodplain garden from 17 different crops were analyzed for Hg. All crop samples (except for nine) had less than 0.1 μg Hg g−1wet weight basis (ww). Many samples were less than the method detection limit (MDL) of 0.003 μg Hg g−1ww. Based on the measured Hg concentrations and several conservative assumptions (e.g., Hg assumed present when less than MDL; 100% consumption from the geographical area in which study was conducted; and 100% bioavailable Hg as methyl Hg), consumption of crops with these Hg levels is not expected to be a significant route of Hg exposure. [ABSTRACT FROM AUTHOR]

The majority of hepatitis C virus (HCV)-infected individuals progress from acute to chronic disease, despite the presence of a strong humoral immune response to the envelope glycoproteins E1 and E2. When expressed in mammalian cells, E1 and E2 form both noncovalently linked E1E2 heterodimers, believed to be properly folded, and disulfide-linked, high-molecular-weight aggregates that are misfolded. Previously, we identified 10 human monoclonal antibodies (HMAbs) that bind E2 glycoproteins from different genotypes. Here we demonstrate that one of these HMAbs, CBH-2, is unique in its ability to distinguish between properly folded and misfolded envelope proteins. This HMAb recognizes HCV-E2 only when complexed with E1. The E1E2 complexes recognized by CBH-2 are noncovalently linked heterodimers and not misfolded disulfide-linked, high-molecular-weight aggregates. The E1E2 heterodimers seen by CBH-2 no longer associate with the endoplasmic reticulum chaperone calnexin and are likely to represent the prebudding form of the HCV virion. [ABSTRACT FROM AUTHOR]

The serum IgE levels of asthmatic subjects from Papua, New Guinea (PNG) were similar to those of corresponding control subjects but significantly higher than Caucasian asthmatics from Western Australia (AUS). Notwithstanding these differences in total IgE, the levels of IgE antibodies to D. pteronyssinus (RAST units) were similar in both asthmatic groups. The mite specific IgE antibody levels were independent of those to Ascaris and hookworm, suggesting that antigenic competition is not a factor of importance in sensitization to environmental allergens in the tropics. This study does not support the proposal that the low prevalence of allergic disease in tropical areas where parasitism is endemic is attributed to mast cell blockade through saturation of IgE receptors. [ABSTRACT FROM AUTHOR]

Transcutaneous cardiac pacing using the Pace-Aid (Cardiac Resuscitator Corporation) was assessed in 32 emergency patients presenting with profound bradycardia or asystole who had lolled to recover with advanced life support including the use of epinephrine. Pacing stimuli, pulse width 20 ms at 50, 100, or 200 mA, were delivered through two 8 cm gel-pod electrodes placed antero-posteriorly on the chest. By ECG criteria, definite electrical capture was achieved in a total of five patients and possible capture in a further 16. Of the 21 patients presenting in asystole 11 showed possible electrical capture only. No evidence of capture was seen in one third of the patients studied. Use of the Pace-Aid resulted in a palpable pulse in a total of seven patients. Four of the 11 patients with profound bradycardia survived to receive temporary transvenous pacing; two were eventually discharged. None in the asystolic group survived. Difficulties in using the Pace-Aid resulted from electrical overload by the pacing impulse that obscured the evidence for electrical capture, and intense muscle contraction that hindered reliable palpation of the arterial pulse. Transcutaneous pacing can occasionally be of value even at a late stage in the emergency treatment of profound bradycardia but is unlikely to be worthwhile in complete asystole. [ABSTRACT FROM AUTHOR]

The article discusses the gemological properties of five faceted samples of sphenes from Afghanistan that were donated to the Gemological Institute of America (GIA) for examination. Gemological testing revealed a brownish yellow to greenish yellow color, a strong with predominantly red and green flashes of dispersion, a hydrostatic specific gravity of 3.53-3.54, and a weak pink Chelsea filter. Energy-dispersive X-ray fluorescence (EDXRF) spectroscopy of three of the samples indicated silicon, calcium and titanium.

The article reports on the discovery of chromium/vanadium (CR/V)-bearing kyanite from Madagascar. A blue kyanite was faceted by Fabrice Danet in 2004, from a mixed parcel of mostly rhodolite, zircon, and amethyst that was represented as coming from the eastern coastal area of Madagascar. After preliminary testing, the stone was found to contain Cr and V. Danet donated the stone to the Gemological Institute of America for further testing. The properties of the stone are comparable to those reported for kyanite by R. Webster in the book "Gems."

The article describes some samples of brownish orange uvite from Afghanistan loaned by Farooq Hashmi to the Gemological Institute of America (GIA). Aside from the uvite, Hashmi also loaned GIA a number of fragments and well-formed crystals of green tourmaline. The green tourmaline was purchased in mid-2006 during a trip to Peshawar, Pakistan. The colors of the crystals vary from medium-dark to dark green with some of the samples darker green toward the pyramidal termination. Some of the samples were almost flat and fairly smooth.

The article describes the olive green and chrome green diopside varieties from Badakhshan, Afghanistan. Farooq Hashimi of Intimate Gems purchased the gem-quality rough while on a trip to Peshawar, Pakistan. The diopside varieties came from separate deposits. The olive green diopside contained abundant inclusions, and the limited quantities of clean transparent pieces mostly weighed less than three grams each. Meanwhile, the chrome diopside was said to have been cobbed from pods of material measuring up to several centimeters in diameter that were hosted by the black mica schist.

The article discusses the gemological properties of six faceted uvite-dravite tourmalines that were loaned to the Gemological Institute of America (GIA). The specimens exhibited a brownish orange, brown-yellow, orangy yellow, brownish yellowish green and yellowish green colors, with one stone appearing bicolored in yellow-green and reddish brown due to its cut revealing strong pleochroism face-up. The stones showed a birefringence of 0.019-0.021, a hydrostatic specific gravity of 3.05-3.07 and a fluorescence of long-wave ultraviolet (UV) radiation.

The article discusses the gemological properties of some rough and cut examples of lime green herderite that were loaned to the Gemological Institute of America (GIA) for identification. The two faceted herderites showed weak-to-moderate green and yellowish green pleochroism, a transparent diaphaneity, refractive indices of 1.587-1.616 and 1.586-1.616, birefringence of 0.029 and 0.030, hydrostatic specific gravity of 3.02 and 3.04, and a weak-to-moderate blue and moderate-to-strong blue to long wave ultraviolet (UV) radiation. Microscopic examination of both samples revealed moderate-to-strong doubling and numerous partially healed fractures with negative crystals.

The article describes a selection of sphene from Pakistan featured by Dudley Blauwet at the American Gem Trade Association (AGTA) show. The stones were initially obtained in mid-2004 which reportedly came from a mining area called Mulla Ghani Baba. The stones are a saturated golden orange color with intense dispersion with red flash. It ranges from yellow to orange-brown, with greenish brown and greenish yellow colors seen less commonly. Some samples were loaned and donated to the Gemological Institute of America (GIA) for examination. Energy-Dispersive X-Ray Fluorescence (EDXRF) spectroscopy revealed a combination of silicon, calcium and titanium in the samples, along with varying amounts of iron, niobium, yttrium, zirconium and strontium.

The article describes a transparent faceted sillimanite discovered in the Vishakhapatnam region of Andra Pradesh, India presented at the American Gem Trade Association (AGTA) show by Anil B. Dholakia Inc. The stones all have checkerboard cuts with various colors ranging from greenish yellow, near colorless, grayish green, green-brown, brownish orange-yellow and violetish gray. Several samples were examined by the Gemological Institute of America (GIA). Three largest stones were selected which are of yellow-green and yellow and grayish green in color. Based on microscopic examination, the two yellow-green stones contained parallel iridescent needles while the greenish yellow stone contained fine whitish parallel needles.

The article describes pyrope-spessartine garnets from Tanzania. The stones are marketed as Imperial garnet and have been in production since late 2005 from Lindi Province in Madagascar. The stones were presented by Steve Ulatowski on New Era Gems at the 2006 Pueblo Gems & Mineral Show in Tucson, Arizona. He claimed that the stone is quite rare and the largest stone with good clarity. A sample cut was examined by the Gemological Institute of America (GIA) and revealed that the stone was pink in color in both incandescent and daylight but brownish pinkisho range in fluorescent. Iridescent needles, subhedral transparent bifringent crystals nad dust-like particles were shown by microscopic examination.

The article discusses the gemological properties of a glass imitation of alexandrite being sold a Zandrite and donated to the Gemological Institute of America's (GIA) collection by Samuel Gullo of Tsavo Gem Imports for examination. The sample's refractive index was 1.538 and its hydrostatic specific gravity was 2.82. The blue-to purple sample showed weak anomalous double refraction and a very weak orangy pink Chelsea filter reaction, and was inert to both long- and short-wave ultraviolet (UV) radiation. Energy-dispersive X-ray fluorescence (EDXRF) spectroscopy found silicon as a major constituent, and trace amounts of potassium, copper, zinc, zirconium, cerium, and neodymium.