Effect of omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation to lactating sows on growth and indicators of stress in the postweaned pig1,2.

Dietary omega-3 polyunsaturated fatty acids (n-3 PUFA) are precursors for lipid metabolites that reduce inflammation. Two experiments were conducted to test the hypothesis that enriching the sow diet in n-3 PUFA during late gestation and throughout lactation reduces stress and inflammation and promotes growth in weaned pigs. A protected fish oil product (PFO; Gromega) was used to enrich the diet in n-3 PUFA. In the initial experiment, time-bred gilts were fed a gestation and lactation diet supplemented with 0% (control; n = 5), 0.25% (n = 4), 0.5% (n = 4), or 1% (n = 5) PFO from 101 ± 2 d of gestation to day 16 of lactation. Adding 1% PFO to the diet increased the n-3:n-6 PUFA ratio in colostrum and milk compared with controls (P = 0.05). A subsequent experiment was performed to determine whether supplementing the sow diet with 1% PFO improved growth and reduced circulating markers of acute inflammation and stress in the offspring. Plasma was harvested from piglets (16 per treatment group) on day 0 (d of weaning) and days 1 and 3 postweaning. Pigs from the 1% PFO treatment group weighed more (P = 0.03) on day 3 postweaning and had a greater (P ˂ 0.05) n-3:n-6 PUFA ratio in plasma on each day sampled compared with 0% PFO controls. There was an overall treatment effect on plasma total cortisol (P = 0.03) and haptoglobin (P = 0.04), with lesser concentrations in pigs on the 1% PFO diet. Plasma corticosteroid-binding globulin (CBG) concentrations were not different between treatment groups but were less (P ˂ 0.001) on days 1 and 3 when compared with day 0. The resultant free cortisol index [FCI (cortisol/CBG)] was less (P = 0.02) on days 1 and 3 for pigs from the 1% treatment group compared with the controls. An ex vivo lipopolysaccharide (LPS) challenge of whole blood collected on days 0 and 1 was used to determine whether 1% PFO attenuated release of inflammatory cytokines (IL-1ß, IL-6, and TNF-α). Blood from pigs within the 1% PFO treatment group tended (P = 0.098) to have a lesser mean concentration of TNF-α in response to LPS compared with blood from controls. These results suggest that providing a PFO supplement as 1% of the diet to sows beginning in late gestation and during lactation can increase the n-3:n-6 PUFA ratio in their offspring, which may improve growth and reduce the acute physiological stress response in the pigs postweaning.

Arbuscular mycorrhizal symbiosis alters stomatal conductance of host plants more under drought than under amply watered conditions: a meta-analysis.

Stomata regulate rates of carbon assimilation and water loss. Arbuscular mycorrhizal (AM) symbioses often modify stomatal behavior and therefore play pivotal roles in plant productivity. The size of the AM effect on stomatal conductance to water vapor (g s ) has varied widely, has not always been apparent, and is unpredictable. We conducted a meta-analysis of 460 studies to determine the size of the AM effect under ample watering and drought and to examine how experimental conditions have influenced the AM effect. Across all host and symbiont combinations under all soil moisture conditions, AM plants have shown 24 % higher g s than nonmycorrhizal (NM) controls. The promotion of g s has been over twice as great during moderate drought than under amply watered conditions. The AM influence on g s has been even more pronounced under severe drought, with over four times the promotion observed with ample water. Members of the Claroideoglomeraceae, Glomeraceae, and other AM families stimulated g s by about the same average amount. Colonization by native AM fungi has produced the largest promotion. Among single-AM symbionts, Glomus deserticola, Claroideoglomus etunicatum, and Funneliformis mosseae have had the largest average effects on g s across studies. Dicotyledonous hosts, especially legumes, have been slightly more responsive to AM symbiosis than monocotyledonous hosts, and C3 plants have shown over twice the AM-induced promotion of C4 plants. The extent of root colonization is important, with heavily colonized plants showing ×10 the g s promotion of lightly colonized plants. AM promotion of g s has been larger in growth chambers and in the field than in greenhouse studies, almost ×3 as large when plants were grown under high light than low light, and ×2.5 as large in purely mineral soils than in soils having an organic component. When AM plants have been compared with NM controls given NM pot culture, they have shown only half the promotion of g s as NM plants not given anything at inoculation to control for associated soil organisms. The AM effect has been much greater when AM plants were larger or had more phosphorus than NM controls. These findings should assist in further investigations of predictions and mechanisms of the AM influence on host g s .

Bioaccumulation and speciation of selenium in fish and insects collected from a mountaintop removal coal mining-impacted stream in West Virginia.

A major contaminant of concern for mountaintop removal/valley fill (MTR/VF) coal mining is selenium (Se), an essential micronutrient that can be toxic to fish. Creek chubs (Semotilus atromaculatus), green sunfish (Lepomis cyanellus), and composite insect samples were collected in March-July, 2011-2013 at two sites within the Mud River, West Virginia. One site (MR7) receives MTR/VF coal mining effluent, while the reference site (LFMR) does not. MR7 water had significantly higher concentrations of soluble Se (p < 0.01) and conductivity (p < 0.005) compared to LFMR. MR7 whole insects contained significantly higher concentrations of Se compared to LFMR insects (p < 0.001). MR7 creek chubs had significantly higher Se in fillets, liver, and ovary tissues compared to LFMR samples (p < 0.0001, p < 0.0001, and p < 0.02, respectively). MR7 green sunfish fillets contained significantly higher Se (p < 0.0001). Histological examination showed LFMR creek chub gills contained a typical amount of parasitic infestations; however MR7 gills contained minimal to no visible parasites. X-ray absorption spectroscopic analyses revealed that MR7 whole insects and creek chub tissues primarily contained organic Se and selenite. These two species of Mud River fish were shown to specifically accumulate Se differently in tissues compartments. Tissue-specific concentrations of Se may be useful in determining potential reproductive consequences of Se exposure in wild fish populations.

Lung cancer incidence in Canadian petroleum workers.

OBJECTIVES: This study's purpose was to conduct a more in-depth analysis of the potential association between lung cancer, occupational exposures and smoking using data on cohort members from a Canadian petroleum company and refined statistical analyses. METHODS: Information on various exposures including asbestos and petroleum coke dust, as well as job type and operating segment were collected via manual and computerised company records. We performed life-table analyses, Poisson regression and restricted cubic splines to model exposure-response patterns while controlling for smoking status and age. Model diagnostics included the assessment of dispersion and offset parameters. RESULTS: These analyses show that lung cancer risk is strongly related to age and smoking, and to a lesser extent to province of last residence. When controlling for these covariates, there is suggestive evidence that maintenance work may also be related to lung cancer risk. Some analyses also indicate that asbestos exposure may be associated with lung cancer risk, although a clear exposure-response trend is not seen. Other exposures, including petroleum coke dust, were not strongly related to lung cancer risk, particularly when expressed as a continuous measure. CONCLUSIONS: These data suggest that maintenance work may be associated with lung cancer incidence, although exposures to the single agents studied did not emerge as strong predictors of lung cancer incidence. Maintenance work may be a surrogate for general exposures to several agents (eg, polycyclic aromatic hydrocarbons, metals, welding fumes, radiation, etc), although these results may be affected by residual confounding due to smoking or other socio-demographic factors.

Spider glue proteins have distinct architectures compared with traditional spidroin family members.

Adhesive spider glues are required to perform a variety of tasks, including web construction, prey capture, and locomotion. To date, little is known regarding the molecular and structural features of spider glue proteins, in particular bioadhesives that interconnect dragline or scaffolding silks during three-dimensional web construction. Here we use biochemical and structural approaches to identify and characterize two aggregate gland specific gene products, AgSF1 and AgSF2, and demonstrate that these proteins co-localize to the connection joints of both webs and wrapping silks spun from the black widow spider, Latrodectus hesperus. Protein architectures are markedly divergent between AgSF1 and AgSF2, as well as traditional spider silk fibroin family members, suggesting connection joints consist of a complex proteinaceous network. AgSF2 represents a nonglycosylated 40-kDa protein that has novel internal amino acid block repeats with the consensus sequence NVNVN embedded in a glycine-rich matrix. Analysis of the amino acid sequence of AgSF1 reveals pentameric QPGSG iterations that are similar to conserved modular elements within mammalian elastin, a rubber-like elastomeric protein that interfaces with collagen. Wet-spinning methodology using purified recombinant proteins show AgSF1 has the potential to self-assemble into fibers. X-ray fiber diffraction studies performed on these synthetic fibers reveal the presence of noncrystalline domains that resemble classical rubber networks. Collectively, these data support that the aggregate gland serves to extrude a protein mixture that contains substances that allow for the self-assembly of fiber-like structures that interface with dragline silks to mediate prey capture.

Vagal afferents mediate early satiation and prevent flavour avoidance learning in response to intraperitoneally infused exendin-4.

Glucagon-like peptide-1 receptor (GLP-1R) agonists such as exendin-4 (Ex-4) affect eating and metabolism and are potential candidates for treating obesity and type II diabetes. In the present study, we tested whether vagal afferents mediate the eating-inhibitory and avoidance-inducing effects of Ex-4. Subdiaphragmatic vagal deafferentation (SDA) blunted the short-term (< 1 h) but not long-term eating-inhibitory effect of i.p.-infused Ex-4 (0.1 µg/kg) in rats. A dose of 1 µg/kg Ex-4 reduced 0.5, 1, 2 and 4 h cumulative food intake in SDA and sham-operated rats to a similar extent. Paradoxically, SDA but not sham rats developed a conditioned flavour avoidance (CFA) after i.p. Ex-4 (0.1 µg/kg). SDA completely blunted the induction of c-Fos expression by Ex-4 in the hypothalamic paraventricular nucleus. Ex-4, however, increased the number of c-Fos expressing cells, independent of intact vagal afferents, in the nucleus accumbens and in the central nucleus of the amygdala, the lateral external parabrachial nucleus, the caudal ventrolateral medulla and the dorsal vagal complex. These data suggest that intact vagal afferents are only necessary for the full expression of the early satiating effect of Ex-4 but not for later eating-inhibitory actions, when circulating Ex-4 might reach the brain via the circulation. Our data also dissociate the satiating and avoidance-inducing effects of the low Ex-4 dose tested under our conditions and suggest that vagal afferent signalling may protect against the development of CFA. Taken together, these findings reveal a complex role of vagal afferents in mediating the effects of GLP-1R activation on ingestive behaviour.

An efficient and rapid transgenic pollen screening and detection method using flow cytometry.

Assaying for transgenic pollen, a major vector of transgene flow, provides valuable information and essential data for the study of gene flow and assessing the effectiveness of transgene containment. Most studies have employed microscopic screening methods or progeny analyses to estimate the frequency of transgenic pollen. However, these methods are time-consuming and laborious when large numbers of pollen grains must be analyzed to look for rare transgenic pollen grains. Thus, there is an urgent need for the development of a simple, rapid, and high throughput analysis method for transgenic pollen analysis. In this study, our objective was to determine the accuracy of using flow cytometry technology for transgenic pollen quantification in practical application where transgenic pollen is not frequent. A suspension of non-transgenic tobacco pollen was spiked with a known amount of verified transgenic tobacco pollen synthesizing low or high amounts of green fluorescent protein (GFP). The flow cytometric method detected approximately 75% and 100% of pollen grains synthesizing low and high amounts of GFP, respectively. The method is rapid, as it is able to count 5000 pollen grains per minute-long run. Our data indicate that this flow cytometric method is useful to study gene flow and assessment of transgene containment.

Pyriform spidroin 1, a novel member of the silk gene family that anchors dragline silk fibers in attachment discs of the black widow spider, Latrodectus hesperus.

Spiders spin high performance threads that have diverse mechanical properties for specific biological applications. To better understand the molecular mechanism by which spiders anchor their threads to a solid support, we solubilized the attachment discs from black widow spiders and performed in-solution tryptic digests followed by MS/MS analysis to identify novel peptides derived from glue silks. Combining matrix-assisted laser desorption ionization tandem time-of-flight mass spectrometry and cDNA library screening, we isolated a novel member of the silk gene family called pysp1 and demonstrate that its protein product is assembled into the attachment disc silks. Alignment of the PySp1 amino acid sequence to other fibroins revealed conservation in the non-repetitive C-terminal region of the silk family. MS/MS analysis also confirmed the presence of MaSp1 and MaSp2, two important components of dragline silks, anchored within the attachment disc materials. Characterization of the ultrastructure of attachment discs using scanning electron microscopy studies support the localization of PySp1 to small diameter fibers embedded in a glue-like cement, which network with large diameter dragline silk threads, producing a strong, adhesive material. Consistent with elevated PySp1 mRNA levels detected in the pyriform gland, MS analysis of the luminal contents extracted from the pyriform gland after tryptic digestion support the assertion that PySp1 represents one of the major constituents manufactured in the pyriform gland. Taken together, our data demonstrate that PySp1 is spun into attachment disc silks to help affix dragline fibers to substrates, a critical function during spider web construction for prey capture and locomotion.

Aciniform spidroin, a constituent of egg case sacs and wrapping silk fibers from the black widow spider Latrodectus hesperus.

Spiders produce high performance fibers with diverse mechanical properties and biological functions. Molecular and biochemical studies of spider egg case silk have revealed that the main constituent of the large diameter fiber contains the fibroin TuSp1. Here we demonstrate by SDS-PAGE and protein silver staining the presence of a distinct approximately 300-kDa polypeptide that is found in solubilized egg case sacs. Combining matrix-assisted laser desorption ionization tandem time-of-flight mass spectrometry and reverse genetics, we have isolated a novel gene called AcSp1-like and demonstrate that its protein product is assembled into the small diameter fibers of egg case sacs and wrapping silks from the black widow spider, Latrodectus hesperus. BLAST searches of the NCBInr protein data base using the amino acid sequence of AcSp1-like revealed similarity to AcSp1, an inferred protein proposed to be a component of wrapping silk. However, the AcSp1-like protein was found to display more nonuniformity in its internal iterated repeat modules than the putative AcSp1 fibroin. Real time quantitative PCR analysis demonstrates that the AcSp1-like gene displays an aciniform gland-restricted pattern of expression. The amino acid composition of the fibroins extracted from the luminal contents of the aciniform glands was remarkably similar to the predicted amino acid composition of the AcSp1-like protein, which supports the assertion that AcSp1-like protein represents the major constituent stored within the aciniform gland. Collectively, our findings provide the first direct molecular evidence for the involvement of the aciniform gland in the production of a common fibroin that is assembled into the small diameter threads of egg case and wrapping silk of cob weavers.

Analysis of aqueous glue coating proteins on the silk fibers of the cob weaver, Latrodectus hesperus.

Elucidation of the molecular composition and physical properties of spider glue is necessary to understand its function in the mechanics of the web and prey capture. Previous reports have indicated that components of the adhesive coating contain inorganic molecules, phosphorylated glycoproteins, lipids, and organic low-molecular mass (LMM) compounds. Using a proteomic strategy, we have investigated the viscid, aqueous components that coat different silk fiber types from the black widow spider, Latrodectus hesperus. After in-solution tryptic digestion of the aqueous protein material extracted from egg case sacs, gumfooted lines, and the web scaffolding connection joints, followed by peptide analysis using MALDI tandem TOF mass spectrometry, we demonstrate that these fibers are coated with common peptides. Utilizing a reverse genetics approach, we have isolated the cDNAs encoding two distinct fiber coating products, which we have named spider coating peptide 1 and 2 (SCP-1 and SCP-2). Secreted forms of SCP-1 and SCP-2 contain 36 and 19 amino acids, respectively, and their primary sequences display no significant similarities to ensemble repeat units from traditional fibroins. Quantitative real-time reverse transcription PCR analyses show that these mRNAs are chiefly produced by the aggregate gland. Biochemical studies also demonstrate that the SCP-1 peptide has intrinsic metal binding properties, suggesting a role of peptide-metal ion interactions with the fiber constituents to enhance thread performance. Collectively, these investigations are the first to reveal a novel role for the aggregate gland in the production of peptides that coat spider silk threads.

Long-term effects of consumption of a novel fat emulsion in relation to body-weight management.

OBJECTIVE: To assess weight maintenance after weight loss by consumption of yoghurt with a novel fat emulsion (Olibra) including effects on body composition, resting energy expenditure (REE), fat oxidation, hunger feelings and satiety hormones. DESIGN: A randomized, placebo-controlled, double-blind, parallel design. A 6-week weight loss period (2.1 MJ/day) was followed by 18 weeks weight maintenance with test (Olibra) or placebo yoghurt. SUBJECTS: Fifty overweight women (age: 18-58 years, body mass index (BMI) 25-32 kg/m2). MEASUREMENTS: In weeks 1, 7 and 25, a satiety test with questionnaires and blood samples for analysis of satiety hormones. In weeks 2, 8 and 26, REE, body weight and body composition. RESULTS: During weight maintenance after significant body weight reduction, there was no significant increase in body weight in the test group (1.1+/-3.4 kg); the placebo group did gain weight (3.0+/-3.1 kg, P<0.001). Compared to the placebo group, the test group was less hungry 4 h after yoghurt consumption in week 25 (P<0.05) and showed increased glucagon like peptide-1 values 180 min after yoghurt consumption (week 25 vs week 1, P<0.05). Measured REE as a function of fat-free mass (FFM) was significantly higher than predicted REE (P<0.05) in week 26 for the test group, but not for the placebo group. Fat mass (FM) was significantly more decreased in the test group (6.5+/-4.1 kg) compared to the placebo group (4.1+/-3.6 kg) (week 26 vs week 2, P<0.05). CONCLUSION: Consumption of Olibra yoghurt improved weight maintenance compared to placebo, which can be explained by the relatively higher REE as a function of FFM, relatively higher decrease in FM and the relatively lower increase in hunger.

Spider egg case core fibers: trimeric complexes assembled from TuSp1, ECP-1, and ECP-2.

Spider silk proteins are well-known for their extraordinary mechanical properties, displaying remarkable strength and toughness. In this study, matrix-assisted laser desorption ionization (MALDI) tandem time-of-flight (TOF) mass spectrometry (MS/MS) and reverse genetics were used to isolate a new cDNA sequence that encodes for a protein assembled into egg case silk from the black widow spider, Latrodectus hesperus. Analysis of the primary sequence of this protein reveals approximately 52% identity to the egg case protein 1 (ECP-1) fibroin-like family member. On the basis of the similarity in the primary sequence and expression pattern, we have named this factor egg case protein 2 (ECP-2). Alignments of ECP-1 and ECP-2 demonstrate highly conserved N termini, with 16 Cys residues found within the first 153 amino acids. Traditional ensemble repeats found within reported fibroins were poorly represented in the primary sequence of ECP-2, but scattered blocks of polyalanine were present, along with a C terminus rich in GA repeats. Reverse transcription quantitative PCR analysis showed that ECP-2 is predominantly expressed in the tubuliform gland. Relative to ECP-1, ECP-2 mRNA levels were determined to be >2-fold higher. MALDI MS/MS analysis of peptide fragments generated from the large-diameter core fiber after enzymatic digestion and acid hydrolysis demonstrated the presence of a fiber that is trimeric in nature, containing tubuliform spidroin 1 (TuSp1), ECP-1, and ECP-2. We also report an additional primary sequence for TuSp1, demonstrating that TuSp1 contains two Cys residues within a nonrepetitive N-terminal region. In combination with the distinctive protein architectures of ECP-1 and ECP-2, along with their co-localization with TuSp1 in the core fiber, our findings suggest that ECP-1 and ECP-2 play important structural roles in the egg case silk fiber.

Incorporation of alpha-tocopherol and linoleic acid in fresh lambs by feeding chemically treated dietary supplements containing dl-alpha-tocopheryl acetate and sunflower oil.

The effects of feeding chemically treated dietary supplements (CTDS) containing sunflower oil and dl-alpha-tocopheryl acetate (TA) on alpha-tocopherol content and fatty acid profile in edible tissues of lambs were estimated. Compared with lambs fed control diet (CD), lambs fed CD plus 250 IU of either TA or CTDS increased serum alpha-tocopherol. The CTDS-fed lambs further increased serum alpha-tocopherol by 29% over those fed CD plus 250 IU of TA. Lambs supplemented with TA or CTDS increased alpha-tocopherol in muscle and adipose tissues as compared with lambs fed CD. The CTDS-fed lambs had higher levels of alpha-tocopherol in gluteus medius (7.55 vs 6.05 mug/g), psoas major (7.43 vs 6.02 mug/g), and subcutaneous fat (12.6 vs 9.98 mug/g) compared with the TA-fed lambs. Feeding lambs CTDS also substantially increased levels of linoleic acid in the adipose tissues while decreasing the content of palmitic and oleic acids.

Environmental impact and health risks associated with greywater irrigation: a case study.

There is an increasing trend to use greywater for irrigation in households. This is partly due to the notion that greywater is of better quality than wastewater and therefore does not need extensive treatment beyond addressing public health issues. The aim of the study was to evaluate the environmental impact and health risks associated with the use of greywater for irrigation on a small private farm. Over a three-year period, each of three plots on a farm was irrigated with either freshwater, fertilized water, or greywater. Irrigation water and soil from the plots were analyzed for a wide range of chemical and microbial variables. Results suggest that greywater may be of similar quality to wastewater in several parameters such as BOD and faecal coliforms. For some other variables such as boron and surfactants, greywater may even be of worse quality than wastewater. Long-term irrigation of arid loess soil with greywater may result in accumulation of salts, surfactants and boron in the soil, causing changes in soil properties and toxicity to plants. Faecal coliforms did not survive in the soil. Treating greywater before using it for irrigation is recommended, even in places where this is not a requirement.

Araneoid egg case silk: a fibroin with novel ensemble repeat units from the black widow spider, Latrodectus hesperus.

Araneoid spiders use specialized abdominal glands to manufacture up to seven different protein-based silks/glues that have diverse physical properties. The fibroin sequences that encode egg case fibers (cover silk for the egg case sac) and the secondary structure of these threads have not been previously determined. In this study, MALDI tandem TOF mass spectrometry (MS/MS) and reverse genetics were used to isolate the first egg case fibroin, named tubuliform spidroin 1 (TuSp1), from the black widow spider, Latrodectus hesperus. Real-time quantitative PCR analysis demonstrates TuSp1 is selectively expressed in the tubuliform gland. Analysis of the amino acid composition of raw egg case silk closely aligns with the predicted amino acid composition from the primary sequence of TuSp1, which supports the assertion that TuSp1 represents a major component of egg case fibers. TuSp1 is composed of highly homogeneous repeats that are 184 amino acids in length. The long stretches of polyalanine and glycine-alanine subrepeats, which account for the crystalline regions of minor ampullate and major ampullate fibers, are very poorly represented in TuSp1. However, polyserine blocks and short polyalanine stretches were highly iterated within the primary sequence, and (13)C NMR spectroscopy demonstrated that the majority of alanine was found in a beta-sheet structure in post-spun egg case silk. The TuSp1 repeat unit does not display substantial sequence similarity to any previously described fibroin genes or proteins, suggesting that TuSp1 is a highly divergent member of the spider silk gene family.

Egg case protein-1. A new class of silk proteins with fibroin-like properties from the spider Latrodectus hesperus.

Spiders produce multiple types of silk that exhibit diverse mechanical properties and biological functions. Most molecular studies of spider silk have focused on fibroins from dragline silk and capture silk, two important silk types involved in the survival of the spider. In our studies we have focused on the characterization of egg case silk, a third silk fiber produced by the black widow spider, Latrodectus hesperus. Analysis of the physical structure of egg case silk using scanning electron microscopy demonstrates the presence of small and large diameter fibers. By using the strong protein denaturant 8 M guanidine hydrochloride to solubilize the fibers, we demonstrated by SDS-PAGE and protein silver staining that an abundant component of egg case silk is a 100-kDa protein doublet. Combining matrix-assisted laser desorption ionization tandem time-of-flight mass spectrometry and reverse genetics, we have isolated a novel gene called ecp-1, which encodes for one of the protein components of the 100-kDa species. BLAST searches of the NCBInr protein data base using the primary sequence of ECP-1 revealed similarity to fibroins from spiders and silkworms, which mapped to two distinct regions within the ECP-1. These regions contained the conserved repetitive fibroin motifs poly(Ala) and poly(Gly-Ala), but surprisingly, no larger ensemble repeats could be identified within the primary sequence of ECP-1. Consistent with silk gland-restricted patterns of expression for fibroins, ECP-1 was demonstrated to be predominantly produced in the tubuliform gland, with lower levels detected in the major and minor ampullate glands. ECP-1 monomeric units were also shown to assemble into higher aggregate structures through the formation of disulfide bonds via a unique cysteine-rich N-terminal region. Collectively, our findings provide new insight into the components of egg case silk and identify a new class of silk proteins with distinctive molecular features relative to traditional members of the spider silk gene family.

Effect of 1-methylcyclopropene post-harvest treatment on ripening process in cherry tomato fruit (Lycopersicon esculentum var. cerasiforme).

The responses of cherry tomato (Lycopersicon esculentum var. cerasiforme) fruits to post-harvest treatment with 1-MCP were investigated. The maturity stage at which 1-MCP application is most effective in delaying the ripening process was determined, and then the effects of different concentrations (0, 0.035, 0.07 and 0.11 microL/L) of 1-MCP on ethylene production, fruit softening, chlorophyll, lycopene and carotenoids contents of mature green (MG) cherry tomato fruits were assessed. 1-MCP at 0.07 and 0.11 microL/L reduced fruit C(2)H(4) production, delayed the C(2)H(4) peak at ambient temperature. Although 1-MCP at 0.035 microL/L was effective in retarding fruit ripening, it did not suppress endogenous ethylene production. Fruit softening was suppressed by 1-MCP, but its initiation was not affected by 1-MCP. The rate of chlorophyll degradation and its pattern of change with time, and the initiation of lycopene biosynthesis as well as its accumulation were all affected by 1-MCP, but only the accumulation of carotenoids was suppressed. Accumulation of lycopene and carotenoids was almost permanently hampered by 1-MCP at 0.07 microL/L or higher concentrations, and fruit color could not reach the control level even 2 weeks after 1-MCP treatment, indicating the close association of the metabolism of these pigments with ethylene perception. Since the concentration of 0.11 microL/L of 1-MCP was so high that it did not elicit additional response very much than 0.07 microL/L, these concentrations were considered to be practically effective concentrations for cherry tomato at MG stage. The effective 1-MCP concentrations might provide a useful reference to the levels of ethylene receptors as well as ethylene sensitivity in a specific fruit at given development stage.

Ultra-high-frequency acoustic stimulation and tinnitus control: a positron emission tomography study.

Ultra-high-frequency (UHF) external acoustic stimulation with the UltraQuiet device (UQ) has been reported to provide significant relief of severe disabling-type tinnitus. The nuclear medicine imaging technique of positron emission tomography (PET) was selected as a monitoring system to compare objectively metabolic alterations in brain function before and after UHF/UQ and to correlate the PET data with the subjective behavioral response of patients reporting tinnitus relief. PET of brain was completed on 6 patients randomly selected from a cohort of 15 patients included in a protocol to establish long-term tinnitus relief with UHF/UQ. Twelve specific regions of interest (ROI) were selected for PET of brain examination on the basis of results obtained with single-photon emission computed tomography (SPECT) of brain examinations recommended for patients with severe disabling-type tinnitus and demonstrating significant perfusion asymmetries in the right and left brain ROI of the primary auditory cortex; frontal, temporal, parietal, and medial temporal lobes; and cerebellum. PET of brain results included ratios of post- and pre-UHF/UQ stimulation that demonstrated no random response in the selected PET of brain ROI and ratios of post- and pre-UHF/UQ stimulation that demonstrated three categories of response in the selected PET brain ROI for all six patients: hypermetabolism in three patients; hypometabolism in two; and a mixed response in one. Correlation was established for each patient among PET and electrophysiological responses of alteration in minimal masking levels, the residual UHF neuronal response as reflected in the UHF audiogram, and the subjective reported behavioral responses of patients (obtained from outcome questionnaires for tinnitus relief, which focused on tinnitus intensity, annoyance, severity index, and a subjective scale of value of the UHF/UQ device for tinnitus relief. The subjective behavioral response for tinnitus relief with UHF/UQ was found to reflect a dual effect: acoustic stimulation of the residual neuronal function in the UHF range (10-14 kHz) and audiometric thresholds of 40-50 dB sound pressure level (SPL), and the metabolic activity at brain cortex for neuronal reprogramming. The PET of brain categories of response suggested that the UHF/UQ "masking" is predominantly reflective of neuronal reprogramming at the brain cortex. Nuclear medicine PET of brain imaging has provided an objective monitoring system for attempting to establish the efficacy of UHF/UQ for tinnitus relief. No complication of the tinnitus was reported secondary to the PET of brain examination. This limited PET of brain study supports the clinical recommendation of the efficacy of UHF/UQ external acoustic stimulation for a selected population of patients with tinnitus of the severe disabling type.

Evolution of diabetes medical nutrition therapy.

Research supports the importance of medical nutrition therapy in achieving diabetes treatment goals. For persons requiring insulin therapy, the first priority is to integrate an insulin regimen into the patient's lifestyle. For type 2 diabetes, the priority is to focus on lifestyle strategies (that is, nutrition and exercise) that will improve metabolic outcomes at diagnosis and as the disease progresses. Patients with diabetes need nutrition recommendations that are supported by scientific evidence and that can be easily understood and translated into everyday life. To achieve positive outcomes, a coordinated team effort that provides continued education and support is essential.