Genetic implications of kernel NIR hardness on milling and flour quality in bread wheat

While quantitative measurements of wheat (Triticum aestivum L) kernel hardness are important for market classification of cultivars, their genetic relationship to end-use quality in breeding populations is not well established. After verifying that divergent selection for hardness score (HS) based on near- infrared reflectance (NIR) spectroscopy was effective, the objective was to determine correlated selection responses in milling and flour quality of two hard red winter populations differing widely in parental origin. Selection was applied in the F₃ generation using replicated field plots at two locations. Selection response was evaluated in the F₄ generation at the same locations the following year. Selection for high HS (harder kernels) increased kernel protein concentration in both populations, while low HS selection decreased it. Selection for HS had no consistent and detectable impact on flour yield or physical dough properties (mixograph absorption, mixing time, and mixograph rating or tolerance). Selection for high HS decreased SDS sedimentation volume adjusted for flour protein concentration in both populations, but the magnitude of the response was small (?1.7 ml in actual units; ?0.3 ml after adjustment). Because correlative effects of NIR hardness were primarily expressed in protein quantity and not protein quality, milling and flour quality must be considered independently of NIR hardness if genetic improvement in those traits is desired.     

The effect of WIC and Medicaid on infant mortality in the United States

OBJECTIVES: This study examine the impact of participation in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) and Medicaid on risk of infant death in the United States. METHODS: The 1988 National Maternal and Infant Health Survey was used to consider the risk of endogenous and exogenous death among infants of women participating in WIC and Medicaid during pregnancy and the infant's first year. RESULTS: Participation in the WIC program during pregnancy and infancy was associated with a reduced risk of endogenous and exogenous infant deaths (odds ratios [ORs] = 0.68 and 0.62, respectively). The risk of endogenous death among infants whose mothers participated in Medicaid during pregnancy was equal to that of the privately insured (OR = 1.04). Uninsured infants faced higher risks of endogenous death (OR = 1.42). CONCLUSIONS: These results show that it is important to consider the net effect of WIC and Medicaid participation and to differentiate both the timing of program receipt and cause of death. Evidence suggests that WIC and Medicaid programs have beneficial effects for poor women and their infants.     

Multiple sclerosis in Fife

Patients in Fife with multiple sclerosis were identified from three sources: a postal questionnaire to all general practices in Fife, hospital discharge data, rehabilitation service database. A total of 508 patients were identified in a population of 354,273 giving a crude prevalence rate of 143/100,000. The Standardised Prevalence Rate was 178/100,000. The sex ratio was 2.43 females to males. The prevalence was higher than identified in southern parts of the United Kingdom and similar to northern Scotland. A total of 200 (40%) cases were identified as having relapsing-remitting disease and of these 151 were ambulant, making them eligible for treatment with interferon beta-lb under current licensing criteria. Only 90 (60%) of the 151 currently eligible for the drug were under the care of a specialist and almost half the practices felt that they would change their referring habits. These factors may have implications for the workload of specialist clinics.     

Primary structure of trypsin inhibitors from Sicyos australis

Three trypsin inhibitors from Sicyos australis, have been isolated, purified and sequenced. Following protein extraction with ammonium sulphate, the mixture of inhibitors was separated from other proteins by trypsin-affinity chromatography. Subsequent purification of the individual inhibitors was accomplished by reversed-phase HPLC. The primary structures of each inhibitor were elucidated by a combination of protein sequencing and electrospray ionization mass spectrometry (ESI-MS) and tandem mass spectrometry (MS-MS) on both the untreated and the reduced and S-carboxymethylated inhibitors. All three inhibitors show extensive sequence similarity with inhibitors from cultivated Cucurbitaceae species, although there are a number of novel residues present. One of the inhibitors has a blocked N-terminus (pyroglutamic acid) and the use of MS-MS was crucial to the elucidation of its primary structure. ESI-MS was further used to characterize the non-covalent complex between one of the inhibitors and trypsin.     

In-fiber spectrometer using tilted fiber gratings

We demonstrate a compact in-fiber low-resolution spectrometer. Wavelength resolution of 7 nm was achieved using the core radiation-mode coupling of a tilted grating in an optical fiber with a photosensitive cladding. We applied the device to measure the powers of a multiwavelength Raman pump source.     

The effects of acetyl-L-carnitine and sorbinil on peripheral nerve structure, chemistry, and function in experimental diabetes

Nerve conduction velocity (NCV) increased with age in nondiabetic male Wistar rats for the first 26 weeks of life. The NCV of animals made hyperglycemic at age 6 weeks by administration of streptozotocin (STZ) also increases, but at a slower rate. Animals with 4 weeks of hyperglycemia and reduced NCV treated with an aldose reductase inhibitor (sorbinil) or a short-chain acyl-carnitine (acetyl-L-carnitine [ALC]) daily for 16 weeks showed an improvement in NCV. Morphometric studies of tibial nerves collected from animals after 20 weeks of hyperglycemia (age 26 weeks) showed a consistent reduction in the width of the myelin sheath and little change in axon area. The number of large myelinated fibers (>6.5 microns) found in nerves collected from hyperglycemic animals was less than the number found in nondiabetic animals. Treatment of hyperglycemic rats with either sorbinil or ALC was associated with increased NCV, myelin width, and large myelinated fibers. The apparent metabolic effect of these agents was similar for fatty acid metabolism, but different for polyol pathway activity. We conclude that in animals hyperglycemic long enough to slow NCV, sorbinil and/or ALC treatment reduces the functional, structural, and biochemical changes associated with hyperglycemia that occur in the myelin sheath.     

Neural-electronic inhibition simulated with a neuron model implemented in SPICE.

There have been numerous studies presented in the literature related to the simulation of the interaction between biological neurons and electronic devices. A complicating factor associated with these simulations is the algebraic complexity involved in implementation. This complication has impeded simulation of more involved neural-electronic circuitry and consequently has limited potential advancements in the integration of biological neurons with synthetic electronics. In this paper, we describe a modification to a previously proposed SPICE based Hodgkin-Huxley neuron model that demonstrates more physiologically relevant electrical behavior. We utilize this SPICE based neuron model in conjunction with an external circuit that allows for artificial selective inhibition of neural spiking. The neural firing control scheme proposed herein would allow for action potential frequency modulation of neural activity that, if developed further, could potentially be applied to suppress undesirable neural activity that manifests symptomatically as the tremors or seizures associated with specific pathologies of the nervous system.     

Probing the disulfide folding pathway of insulin-like growth factor-I

The crucial step of folding of recombinant proteins presents serious challenges to obtaining the native structure. This problem is exemplified by insulin-like growth factor (IGF)-I which when refolded in vitro produces the native three-disulfide structure, an alternative structure with mispaired disulfide bonds and other isomeric forms. To investigate this phenomenon we have examined the refolding properties of an analog of IGF-I which contains a 13-amino acid N-terminal extension and a charge mutation at position 3 (Long-[Arg3]IGF-I). Unlike IGF-I, which yields 45% of the native structure and 24% of the alternative structure when refolded in vitro, Long-[Arg3]IGF-I yields 85% and 10% of these respective forms. To investigate the interactions that affect the refolding of Long-[Arg3]IGF-I and IGF-I, we acid-trapped folding intermediates and products for inclusion in a kinetic analysis of refolding. In addition to non-native intermediates, three native-like intermediates were identified, that appear to have a major role in the in vitro refolding pathway of Long-[Arg3]IGF-I; a single-disulfide Cys18-Cys61 intermediate, an intermediate with Cys18-Cys61 and Cys6-Cys48 disulfide bonds and another with Cys18-Cys61 and Cys47-Cys52 disulfide bonds. Furthermore, from our kinetic analysis we propose that the Cys18-Cys61, Cys6-Cys48 intermediate forms the native structure, not by the direct formation of the last (Cys47-Cys52) disulfide bond, but by rearrangement via the Cys18-Cys61 intermediate and a productive Cys18-Cys61, Cys47-Cys52 intermediate. In this pathway, the last disulfide bond to form involves Cys6 and Cys48. Finally, we apply this pathway to IGF-I and conclude that the divergence in the in vitro folding pathway of IGF-I is caused by non-native interactions involving Glu3 that stabilize the alternative structure.