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Emissions from volatile chemical products (VCPs) are emerging as a major source of anthropogenic secondary organic aerosol (SOA) precursors. Paints and coatings are an important class of VCPs that emit both volatile and intermediate volatility organic compounds (VOCs and IVOCs). In this study, we directly measured I/VOC emissions from representative water- (latex) and oil-based paints used in the U.S. Paint I/VOC emissions vary by several orders of magnitude by both the solvent and gloss level. Oil-based paints had the highest emissions (10

Mechanospray ionization (MoSI) is a technique that produces ions directly from solution-like electrospray ionization (ESI) but without the need of a high voltage. In MoSI, mechanical vibrations aerosolize solution phase analytes, whereby the resulting microdroplets can be directed into the inlet orifice of a mass spectrometer. In this work, MoSI is applied to biomolecules up to 80 kDa in mass in both denatured and native conditions as well as polymers up to 12 kDa in mass. The various MoSI devices used in these analyses were all comprised of a piezoelectric annulus attached to a central metallic disk containing an array of 4 to 7 μm diameter holes. The devices vibrated in the 100-170 kHz range to generate a beam of microdroplets that ultimately resulted in ion formation. A linear quadrupole ion trap (LIT) and orbitrap mass spectrometer were used in the analysis to investigate higher mass proteins at both native (folded) and denatured (unfolded) conditions. MoSI native mass spectra of proteins acquired on the orbitrap and LIT instrument demonstrated that proteins could remain intact and in a folded state. In the case of native MS of holomyoglobin, the intact folded protein remained mostly bound noncovalently to the heme group, and typically, the spectra showed reduced loss of the heme group by MoSI as compared to ESI. In both non-native and native protein analyses examples, broader often multimodal distributions to lower charge states were observed. When using the LIT instrument, a significant increase in the relative abundance of dimers was observed by MoSI as compared to ESI. The softness of the MoSI technique was evidenced by the lack of fragmentation, the formation of dimers as also noted by others (

ArrayExpress accession: E-TABM-197 from Hormone-Induced Protection against Mammary Tumorigenesis Is Conserved in Multiple Rat Strains and Identifies a Core Gene Expression Signature Induced by Pregnancy

Women who have their first child early in life have a substantially lower lifetime risk of breast cancer. The mechanism for this is unknown. Similar to humans, rats exhibit parity-induced protection against mammary tumorigenesis. To explore the basis for this phenomenon, we identified persistent pregnancy-induced changes in mammary gene expression that are tightly associated with protection against tumorigenesis in multiple inbred rat strains. Four inbred rat strains that exhibit marked differences in their intrinsic susceptibilities to carcinogen-induced mammary tumorigenesis were each shown to display significant protection against methylnitrosourea-induced mammary tumorigenesis following treatment with pregnancy levels of estradiol and progesterone. Microarray expression profiling of parous and nulliparous mammary tissue from these four strains yielded a common 70-gene signature. Examination of the genes constituting this signature implicated alterations in transforming growth factor-β signaling, the extracellular matrix, amphiregulin expression, and the growth hormone/insulin-like growth factor I axis in pregnancy-induced alterations in breast cancer risk. Notably, related molecular changes have been associated with decreased mammographic density, which itself is strongly associated with decreased breast cancer risk. Our findings show that hormone-induced protection against mammary tumorigenesis is widely conserved among divergent rat strains and define a gene expression signature that is tightly correlated with reduced mammary tumor susceptibility as a consequence of a normal developmental event. Given the conservation of this signature, these pathways may contribute to pregnancy-induced protection against breast cancer. (Cancer Res 2006; 66(12): 6421-31)

Students with mental illness can feel stigmatized by their peers and may also have less perceived social support. However, it is thought that people are more likely to view someone more favorably if they perceive them as part of their in-group when sharing a common identity. Thus, an online survey was administered to 152 undergraduate students to investigate whether high in-group identification versus low in-group identification will lead to a more favorable view of a peer regardless of their mental health state and if a peer with stress would still be favored over a peer with mental illness. First, participants rated group identification with a hypothetical peer describing their Hunter College, CUNY experience in an audio clip. Then, participants heard the peer either reveal a mental health state of mental illness or stress. Finally, they rated perceived similarity and social distance toward the peer. Results of a factorial multivariate analysis of variance indicated significant main effects for both in-group identification, F(2, 147) = 8.01, p < .001, partial η2 = .10, and the peer’s mental health state, F(2, 147) = 8.00, p = .001, partial η2 = .10. Although the peer with mental illness was viewed less favorably than the peer with stress, irrespective of group identification, high in-group identification still led to a more positive evaluation of the peer than low in-group identification. These results are important for understanding how increasing awareness of group identification may reduce stigma toward students with mental illness and ultimately reduce barriers to care.

Whilst a number of studies have examined the effects of biodiversity conservation on the delivery of ecosystems, they have been often limited by the scope of the ecosystem services (ES) assessed and often suffer from confounding spatial issues. This paper examines the impacts of nature conservation (designation) on the delivery of a full suite of ES across nine case-studies in the UK, using expert opinion. The case-studies covered a range of habitats and explore the delivery of ES from a ‘protected site’ and a comparable ‘non-protected’ site. By conducting pair-wise comparisons between comparable sites our study is one of the first to attempt to mitigate confounding cause and effect factors in relation to spatial context in correlative studies. Protected sites delivered higher levels of ecosystem services than nonprotected sites, with the main differences being in the cultural and regulating ecosystem services. Against expectations, there was no consistent negative impact of protection on provisioning services across the case-studies. Whilst the analysis demonstrated general patterns and differences in ecosystem delivery between protected and non-protected sites, the individual responses in each case-study highlights the importance of the social, biophysical, economic and temporal context of individual protected areas and the associated management.

We previously identified a SNF1/AMPK-related protein kinase, Hunk, from a mammary tumor arising in an MMTV-neu transgenic mouse. The function of this kinase is unknown. Using targeted deletion in mice, we now demonstrate that Hunk is required for the metastasis of c-myc-induced mammary tumors, but is dispensable for normal development. Reconstitution experiments revealed that Hunk is sufficient to restore the metastatic potential of Hunk-deficient tumor cells, as well as defects in migration and invasion, and does so in a manner that requires its kinase activity. Consistent with a role for this kinase in the progression of human cancers, the human homologue of Hunk is overexpressed in aggressive subsets of carcinomas of the ovary, colon, and breast. In addition, a murine gene expression signature that distinguishes Hunk-wild type from Hunk-deficient mammary tumors predicts clinical outcome in women with breast cancer in a manner consistent with the pro-metastatic function of Hunk in mice. These findings identify a direct role for Hunk kinase activity in metastasis and establish an in vivo function for this kinase.

Epidemiological findings suggest that the consequences of a given oncogenic stimulus vary depending upon the developmental state of the target tissue at the time of exposure. This is particularly evident in the mammary gland, where both age at exposure to a carcinogenic stimulus and the timing of a first full-term pregnancy can markedly alter the risk of developing breast cancer. Analogous to this, the biological consequences of activating oncogenes, such as MYC, can be influenced by cellular context both in terms of cell lineage and cellular environment. In light of this, we hypothesized that the consequences of aberrant MYC activation in the mammary gland might be determined by the developmental state of the gland at the time of MYC exposure. To test this hypothesis directly, we have used a doxycycline-inducible transgenic mouse model to overexpress MYC during different stages of mammary gland development. Using this model, we find that the ability of MYC to inhibit postpartum lactation is due entirely to its activation within a specific 72-hour window during mid-pregnancy; by contrast,MYC activation either prior to or following this 72-hour window has little or no effect on postpartum lactation. Surprisingly, we find that MYC does not block postpartum lactation by inhibiting mammary epithelial differentiation,but rather by promoting differentiation and precocious lactation during pregnancy, which in turn leads to premature involution of the gland. We further show that this developmental stage-specific ability of MYC to promote mammary epithelial differentiation is tightly linked to its ability to downregulate caveolin 1 and activate Stat5 in a developmental stage-specific manner. Our findings provide unique in vivo molecular evidence for developmental stage-specific effects of oncogene activation, as well as the first evidence linking MYC with activation of the Jak2-Stat5 signaling pathway.

Summary 1 The capercaillie Tetrao urogallus and black grouse Tetrao tetrix are declining in the UK, and low breeding success has been identified as the key factor in the decline of the former. To investigate possible causes, breeding productivity was studied in relation to predation, weather, vegetation changes and deer numbers over an 11-year period (1989–99) within native pinewood at Abernethy Forest, Scotland. The abundance of predators (crows Corvus corone and red foxes Vulpes vulpes) was experimentally manipulated in 1992–96 by culling. Productivity (chicks reared per female) was compared between forests with and without experimental predator management. 2 During predator control, the number of breeding crows was reduced from 10 pairs to one. The attempted reduction in red fox abundance was unsuccessful; only small numbers of adults were killed, and neither scat nor den counts declined significantly. 3 Predation on artificial nests containing six hen eggs and a hen egg filled with wax was measured as an index of predator activity from 1991 to 1999. Predation was lowest during the last three years of predator control, 1994–96. Predators could sometimes be distinguished by signs on depredated eggs. Predation on artificial nests by crows was highest during 1991–93. However, after predator removal stopped in 1997 few crows returned, and increased predation on artificial nests did not involve increased signs of crow predation. Pine marten Martes martes numbers increased during the study period and became significant predators of artificial nests. 4 The total number of capercaillie eggs and nests depredated by crows was estimated from the number of depredated capercaillie eggs found and the proportion of crow-predated hen eggs in artificial nests. The values ranged from 18 to 158 eggs over 3 years, equivalent to 3–23 capercaillie nests year−1. 5 Capercaillie productivity was low (

Summary 1 The capercaillie Tetrao urogallus is widely valued as a game bird and an indicator of forest ecosystem quality. In Scotland, its numbers have declined since the 1970s, due primarily to poor breeding success. We investigated whether differences in breeding success among forests are related to predator abundance or to aspects of forest structure, with a view to identifying beneficial management practices. 2 Capercaillie breeding success was estimated in 7–14 forest areas in Scotland each year during 1991–2001. Forest habitat, including ground vegetation, and indices of predator abundance were assessed in each of the 14 areas in 1995. 3 Capercaillie breeding success increased with increasing bilberry Vaccinium myrtillus ground cover, but did not improve further above 15–20% cover. 4 The main predators were carrion crow Corvus corone, fox Vulpes vulpes and raptors. Indices of their abundance were confounded such that their respective effects on capercaillie breeding success could not readily be distinguished. However, capercaillie breeding success was negatively related to a principal component score that represented the combined abundance of crows, foxes and, to a lesser extent, raptors. 5 A management trial in one forest showed that capercaillie bred better when most crows and some foxes were killed than when they were not. 6 An index of pine marten abundance was related neither to the other predator indices nor to capercaillie breeding success. 7 Synthesis and applications. Capercaillie reared more young in forests with more bilberry and fewer predators. Management to improve the breeding success of capercaillie should aim for at least 15–20% bilberry ground cover, and legal control of crows and foxes.

Purpose To report a patient with a branch retinal vein occlusion associated with lipemia retinalis. Design Observational case report. Methods A 58-year-old woman presented with decreased vision and was found to have a branch retinal vein occlusion with massive lipid exudation in the setting of lipemia retinalis. Laboratory testing demonstrated an abnormal lipid profile with a markedly elevated triglyceride level. The setting was a retina service in a major referral center. Results Management of the hypertriglyceridemia with medication, exercise, and dietary modification resolved the lipemia retinalis and was associated with improvement in visual function. Conclusion Although usually not visually significant, lipemia retinalis may be associated with vascular pathology, such as a branch retinal vein occlusion with marked exudative response and decreased visual acuity. Because of potential systemic and ocular complications of lipemia retinalis, these patients should be referred for management of their lipid disorder.

To determine the impact of tumor progression on the reversibility of Neu-induced tumorigenesis, we have used the tetracycline regulatory system to conditionally express activated Neu in the mammary epithelium of transgenic mice. When induced with doxycycline, bitransgenic MMTV-rtTA/TetO-NeuNT mice develop multiple invasive mammary carcinomas, essentially all of which regress to a clinically undetectable state following transgene deinduction. This demonstrates that Neu-initiated tumorigenesis is reversible. Strikingly, extensive lung metastases arising from Neu-induced mammary tumors also rapidly and fully regress following the abrogation of Neu expression. However, despite the near universal dependence of both primary tumors and metastases on Neu transgene expression, most animals bearing fully regressed Neu-induced tumors ultimately develop recurrent tumors that have progressed to a Neu-independent state.

This study was designed to determine whether a soluble dietary fiber supplement containing gum arabic and pectin in apple juice would lower serum lipids in 110 hypercholesterolemic men and women. Subjects were stabilized on an American Heart Association Phase I Diet for 8 wk. Those with elevated low density lipoprotein cholesterol levels, despite dietary modification, continued to follow the diet and were randomly assigned to receive 720 mL/d of apple juice containing 0 (control), 5, 9 or 15 g of gum arabic and pectin (4:1 ratio) for 12 wk, followed by a 6-wk apple juice-only washout phase. Serum lipid profiles, body weight and 3-day diet records were collected at 3-wk intervals. No significant differences among groups were observed in serum lipid responses during treatment or washout. During the treatment phase, mean serum total cholesterol and triglyceride concentrations increased by 3.5 and 28.5%, respectively (all groups combined, P < 0.0001). The high density lipoprotein cholesterol level did not change significantly from baseline in any group. During washout, mean total cholesterol concentration rose by an additional 2.4% (P < 0.05) compared with the value at the end of the treatment period, suggesting that the apple juice used to deliver the fiber supplement may have contributed to the adverse changes observed in the serum lipid profile. These findings do not support the hypothesized hypocholesterolemic effect of the gum arabic/pectin (4:1) mixture studied, but do underline the importance of selecting appropriate vehicles for delivery of dietary fiber mixtures.

Groups of weanling pigs were fed a purified diet containing graded concentrations of olestra ranging from 1.1 to 7.7% (wt/wt) and the NRC's requirements for micronutrients for 12 wk. Each group consisted of 12 pigs, with the exception of the control group, which had 20, with equal numbers of females and castrated males. The purpose of the study was to determine the dose-response effects of olestra on fat-soluble vitamins and selected water-soluble micronutrients. At wk 0, 4, 8 and 12, hematology, clinical chemistry and blood concentrations of vitamins A, E, K and B12, and 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, folate, calcium, iron, zinc and adipose concentration of vitamin E were measured. Cumulative weight gain and feed efficiency were determined weekly. Prothrombin time was measured weekly for the control group and the groups fed 5.5 or 7.7% olestra, and monthly for other groups. Liver concentrations of vitamins A, E, and B12 and iron and bone concentrations of calcium, phosphorus, zinc and ash were measured for 12 pigs killed at wk 0 and for all animals at wk 12. By wk 12, the pigs were eating from 20 to 155 g/d of olestra. Olestra did not affect the pigs' growth or feed efficiency, indicating that the digestion and absorption of macronutrients were unaffected. Olestra reduced tissue concentrations of vitamin A, vitamin E and 25-hydroxyergocalciferol in a dose-responsive manner but did not affect prothrombin time. Olestra had no effect on the status of folate, vitamin B12, zinc or iron. Statistically reduced liver concentrations of vitamin B12 and iron in groups fed 5.5 or 7.7% olestra and a significant trend in bone ash content with olestra intake were possibly due to the poor vitamin A and/or vitamin E status of the pigs.

Ninety normal healthy adults were given 0, 8, 20 or 32 g/d olestra for 8 wk as part of a diet that provided 1 +/- 0.2 of the recommended dietary allowance (RDA) of vitamins A, D, E and K, folate zinc, calcium and iron. In addition, a 20 microg/d supplement of vitamin D was supplied. The diet provided 15% of energy from protein, 35% from fat and 55% from carbohydrate. The purpose of the study was to determine the dose response of olestra on vitamins D, E and K, carotenoids, vitamin B12, folate and zinc. Circulating concentrations of retinol, carotenoids, tocopherols, 25-hydroxy- and 1,25-dihydroxyvitamin D metabolites, phylloquinone, des-gamma-carboxyprothrombin, prothrombin, folate and hematological parameters were measured biweekly, as were urine concentrations of zinc and gamma-carboxyglutamic acid (Gla). Clinical chemistry, urinalysis and vitamin B12 absorption were measured at wk 0 and 8. Olestra reduced serum concentrations of carotenoids, alpha-tocopherol, 25-hydroxyergocalciferol and phylloquinone in a dose-responsive manner. Olestra did not affect Gla excretion, plasma des-gamma-carboxyprothrombin or prothrombin concentrations, prothrombin time, vitamin B12 absorption, overall vitamin D status or the status of folate or zinc. Laboratory evaluations showed no health-related effects of olestra. Subjects in all groups reported common gastrointestinal symptoms such as loose stools, fecal urgency and flatulence, which were transient and generally mild to moderate in severity. These symptoms did not affect protocol compliance or the ability to measure the potential for olestra to affect nutrient availability.

A study was carried out in native pinewoods at Abernethy and Glen Tanar to investigate the effect of forest fences on capercaillie and black grouse. Collisions occurred at a rate of 0.25 and 0.03 per km of fence per month for capercaillie and black grouse respectively. Male capercaillie had a higher proportion of severe and fatal collisions than females. Capercaillie tended to collide with those sections of fence where there were moderately sized pines (8.5 m) close (within 4.4 m) to the fence. Collision sites close to trees were most strongly associated with the height of exposed trunk, suggesting that capercaillie fly under the canopy and fail to see the fence. The annual mortality rate of radio-tagged capercaillie caused by collisions was 32 per cent indicating that this was a major mortality factor. Collisions were most frequent between September and November when capercaillie were dispersing. It is recommended that fences are removed where and when they are unnecessary, or are made more visible, or are set back from old woodland.

To remain competitive in today's business environment, companies must find ways to cut costs without sacrificing the quality of products or services. The Long Island Lighting Company (LILCO) has been able to do just that in the production of wiring diagrams, thanks to a unique PC based CAD software package called Substation/Switchgear Automated Wiring System (SAWS) from Wire Graphics, Inc. The system is not just a drafting tool. It provides the graphic tools necessary to create schematic drawings, wiring diagrams, and associated documentation, and it also allows designers to link the connectivity described in the schematic design with the physical layout of parts on the wiring diagram. This unique feature eliminates the need to manually redraw the connectivity created on the schematics. >

We describe here the cloning of the Aplysia K+ channel AK01a.AK01a codes for a protein of 515 amino acids, shows considerable homology to other cloned potassium channels, and can be classified as a member of the ShakerK+ channel family. Expression of the AK01a channel in Xenopus oocytes produces a rapidly inactivating outward potassium current (IAK01a) resembling the A-type currents of Drosophila Shaker. Gating for this current is shifted to potentials considerably more positive than the traditional A-currents of Aplysia; we have, however, identified a novel transient potassium current (IAdepoI) in a subset of Aplysia neurons that has similar gating and pharmacological properties to IAK01a.

Women who have their first child early in life have a substantially lower lifetime risk of breast cancer. The mechanism for this is unknown. Similar to humans, rats exhibit parity-induced protection against mammary tumorigenesis. To explore the basis for this phenomenon, we identified persistent pregnancy-induced changes in mammary gene expression that are tightly associated with protection against tumorigenesis in multiple inbred rat strains. Four inbred rat strains that exhibit marked differences in their intrinsic susceptibilities to carcinogen-induced mammary tumorigenesis were each shown to display significant protection against methylnitrosourea-induced mammary tumorigenesis following treatment with pregnancy levels of estradiol and progesterone. Microarray expression profiling of parous and nulliparous mammary tissue from these four strains yielded a common 70-gene signature. Examination of the genes constituting this signature implicated alterations in transforming growth factor-β signaling, the extracellular matrix, amphiregulin expression, and the growth hormone/insulin-like growth factor I axis in pregnancy-induced alterations in breast cancer risk. Notably, related molecular changes have been associated with decreased mammographic density, which itself is strongly associated with decreased breast cancer risk. Our findings show that hormone-induced protection against mammary tumorigenesis is widely conserved among divergent rat strains and define a gene expression signature that is tightly correlated with reduced mammary tumor susceptibility as a consequence of a normal developmental event. Given the conservation of this signature, these pathways may contribute to pregnancy-induced protection against breast cancer. (Cancer Res 2006; 66(12): 6421-31)

A novel algorithm (ChipStat) is presented for detecting gene-expression changes from Affymetrix microarray data. The method is used to identify changes in murine mammary development., We describe a novel algorithm (ChipStat) for detecting gene-expression changes utilizing probe-level comparisons of replicate Affymetrix oligonucleotide microarray data. A combined detection approach is shown to yield greater sensitivity than a number of widely used methodologies including SAM, dChip and logit-T. Using this approach, we identify alterations in functional pathways during murine neonatal-pubertal mammary development that include the coordinate upregulation of major urinary proteins and the downregulation of loci exhibiting reciprocal imprinting.

The Drosophila visual system has provided a model to study phototransduction and retinal degeneration. To identify new candidate proteins that contribute to these processes, we conducted a genome-wide screen for genes expressed predominately in the eye, using DNA microarrays. This screen appeared to be comprehensive as it led to the identification of all 22 eye-enriched genes previously shown to function in phototransduction or implicated in retinal degeneration. In addition, we identified 93 eye-enriched genes whose roles have not been previously defined. One of the eye-enriched genes encoded a member of a large family of transmembrane proteins, referred to as tetraspanins. We created a null mutation in the eye-enriched tetraspanin, Sunglasses (Sun), which resulted in light-induced retinal degeneration. We found that the Sun protein was distributed primarily in lysosomes, and functioned in a long-known but poorly understood phenomenon of light-induced degradation of rhodopsin. We propose that lysosomal tetraspanins in mammalian cells may also function in the downregulation of rhodopsin and other G-protein-coupled receptors, in response to intense or prolonged agonist stimulation.

Aberrant activation of Wnt signaling is oncogenic and has been implicated in a variety of human cancers. We have developed a doxycycline-inducibleWnt1transgenic mouse model to determine the dependence of established mammary adenocarcinomas on continued Wnt signaling. Using this model we show that targeted down-regulation of the Wnt pathway results in the rapid disappearance of essentially all Wnt-initiated invasive primary tumors as well as pulmonary metastases. Tumor regression does not require p53 and occurs even in highly aneuploid tumors. However, despite the dependence of primary mammary tumors and metastases on continued Wnt signaling and the dispensability of p53 for tumor regression, we find that a substantial fraction of tumors progress to a Wnt-independent state and that p53 suppresses this process. Specifically, loss of onep53allele dramatically facilitates the progression of mammary tumors to aWnt1-independent state both by impairing the regression of primary tumors following doxycycline withdrawal and by promoting the recurrence of fully regressed tumors in the absence of doxycycline. Thus, although p53 itself is dispensable for tumor regression, it nevertheless plays a critical role in the suppression of tumor recurrence. Our findings demonstrate that although even advanced stages of epithelial malignancy remain dependent upon continued Wnt signaling for maintenance and growth, loss of p53 facilitates tumor escape and the acquisition of oncogene independence.

For many professional sports, nutrition is not recognized as an important component of the team's training program. The implementation of a nutrition program for one professional hockey team has had positive results. Players who had been unable to maintain their weight during the season can now maintain their weight and be prepared for the playoffs. Others have improved their endurance with proper fluid and carbohydrate replacement. Working with the entire time—coaching staff, trainers and players—has led to the success of this program.

Improving outcomes for patients with depression involves selecting the best possible drug therapy. Considerations relevant to drug product selection include: 1) pharmacokinetic issues such as half-life and time to steady-state, and protein binding; 2) pharmacodynamic drug-drug interactions; and 3) drug metabolism-related drug interactions. A comparison of selected antidepressants with an emphasis on venlafaxine's similarities and differences is presented. Based on these parameters, selecting an antidepressant medication, such as venlafaxine, that has a low potential for drug interactions at the Cytochrome P450 (CYP) enzyme system, and is easy to monitor and dose, facilitate successful treatment of patients. Venlafaxine has been evaluated in clinical studies that demonstrate low to negligible drug interaction potential at CYP2D6, CYP1A2, CYP2C19, and CYP3A4. Its short half-life and time to steady-state, when coupled with the extended release characteristics of the preferred dosage formulation allow for once daily dosing and rapid attainment of therapeutic effects. The CYP3A4 system is involved in both first-pass metabolism and systemic clearance of medications. Drug interactions at this isoenzyme have proven to be of high clinical relevance ranging from cardiovascular toxicity and death with commonly used drugs such as cisapride, to subtherapeutic levels of cyclosporine or protease inhibitors leading to transplant rejection or HIV relapse. Reasons for the under detection and reporting of drug interaction mediated adverse events include healthcare system structure, the poor return to follow up of non-adherent patients, the need for greater education and training of clinicians to recognize drug-related adverse events, and the reluctance of patients to spontaneously communicate about the unpleasant effects of their medication.

One hundred two normal healthy males and females were given 0, 8, 20 or 32 g/d olestra to which had been added graded amounts of vitamins A, D and E for 8 wk in a parallel, double-blind study. The primary purpose of the study was to determine the amounts of vitamins D and E needed to offset the effect of olestra on the availability of these vitamins. Serum concentrations of retinol, carotenoids, 25-hydroxyvitamin D metabolites, alpha-tocopherol, phylloquinone, lipids, ferritin and total iron, iron-binding capacity and hematology parameters, plasma concentrations of des-gamma-carboxyprothrombin and prothrombin, and urinary gamma-carboxyglutamic acid (Gla) excretion were measured biweekly. Clinical chemistry and urinalysis parameters, vitamin B12 absorption, and serum 1,25-dihydroxyvitamin D concentration were measured at wk 0 and 8. Serum concentrations of alpha-tocopherol and 25-hydroxyergocalciferol were restored to control concentration by adding 2.1 mg d-alpha-tocopheryl acetate and 0.06 microg ergocalciferol per gram of olestra, respectively, to the diet. Olestra reduced serum concentrations of 25-hydroxyergocalciferol, carotenoids and phylloquinone in a dose-responsive manner but did not affect Gla excretion, plasma des-gamma-carboxyprothrombin and prothrombin concentrations, overall vitamin D status, vitamin B12 absorption or iron status. Laboratory evaluations showed no olestra-related effects. Subjects in all groups reported mild to moderately severe transient gastrointestinal symptoms. These symptoms did not affect study compliance or the integrity of the data.

Psyllium, a water-soluble fiber, has been shown to lower total serum and low-density-lipoprotein (LDL)-cholesterol concentrations in adult hypercholesterolemic subjects and may be effective in the treatment of hypercholesterolemia in children. The effects of a psyllium-enriched cereal were compared with a matched control cereal in a double-blind, crossover fashion in 25 children, 6-18 y old, with hypercholesterolemia. After an 8-wk diet-stabilization period, the subjects were randomly assigned to receive the active or control cereals for 6 wk, followed by a 6-wk washout period and a 6-wk crossover treatment period. Whereas no changes were noted in total and LDL-cholesterol concentrations during consumption of the control cereal, significant changes were seen during the psyllium-cereal periods [0.31 mmol/L (12.1 mg/dL) and 0.28 mmol/L (10.9 mg/dL); P = 0.03 and 0.01, respectively]. The psyllium-enriched cereal was well tolerated throughout the trial. Consumption of the psyllium-enriched cereal resulted in a modest 7% reduction in LDL-cholesterol concentrations compared with the control cereal when used in this pediatric hypercholesterolemic sample. Psyllium offers a potential adjunct to a low-fat diet for the treatment of hypercholesterolemia in the pediatric population because of its ease of incorporation into various foods.

Oat cereals rich in the water-soluble fiber beta-glucan have been studied as a dietary therapy for hypercholesterolemia. To determine the hypocholesterolemic response of beta-glucan in the diet, 156 adults with low-density lipoprotein cholesterol (LDL-C) levels above 4.14 mmol/L (160 mg/dL) or between 3.37 and 4.14 mmol/L (130 and 160 mg/dL) with multiple risk factors were randomized to one of seven groups. Six groups received either oatmeal or oat bran at doses (dry weight) of 28 g (1 oz), 56 g (2 oz), and 84 g (3 oz). A seventh group received 28 g of farina (beta-glucan control). At week 6 of treatment, significant differences were found for both total cholesterol and LDL-C levels among the farina control and the treatment groups who were receiving 84 g of oatmeal, 56 g of oat bran, and 84 g of oat bran, with decreases in LDL-C levels of 10.1%, 15.9%, and 11.5%, respectively. Fifty-six grams of oat bran resulted in significantly greater reductions in LDL-C levels than 56 g of oatmeal. Nutrient analysis shows no difference in dietary fat content between these treatment groups; therefore, the higher beta-glucan content of oat bran most likely explains the significantly greater LDL-C reductions. A dose-dependent reduction in LDL-C levels with oat cereals supports the independent hypocholesterolemic effects of beta-glucan.

A technique is described for explanting and cultivating chicken embryos in plastic drinking cups which have been modified with plastic wrap to reproduce the geometry and dimensions of the egg shell. Successful explantation rates of 97% are possible with a double-window technique, and survivability in cups exceeds that achievable in other in vitro systems (i.e., petri dishes). Long-term survival to the 21st day of incubation is seen routinely. This system with cups is less expensive than that with petri dishes, and simpler than that with plastic wrap/tripods. Thus, this new method of in vitro cultivation of chicken embryos improves upon explantation rate, survivability and system design, and has a wide range of applications in developmental biology, angiogenesis, cancer, and pharmacology research.

We describe a novel algorithm (ChipStat) for detecting gene-expression changes utilizing probe-level comparisons of replicate Affymetrix oligonucleotide microarray data. A combined detection approach is shown to yield greater sensitivity than a number of widely used methodologies including SAM, dChip and logit-T. Using this approach, we identify alterations in functional pathways during murine neonatal-pubertal mammary development that include the coordinate upregulation of major urinary proteins and the downregulation of loci exhibiting reciprocal imprinting.

In Reply. —The issues raised by Drs Sacks and Swain have been addressed in the "Results" and "Comment" sections of our article. Our objective was to determine if a dose-response relationship exists for the hypocholesterolemic effects of oat cereals rich in the water soluble fiber β-glucan. We did not isocalorically control for the higher doses of the oat cereals; however, we believe that our study supports an independent hypocholesterolemic effect for β-glucan for several reasons. There was a highly significant relationship ( r =.81) between the amount of β-glucan consumed and the reduction in LDL-C levels. If we tested the hypothesis of fat replacement as suggested by Sacks and Swain with our study's data, the correlation coefficient between the dose of oat cereals consumed (28, 56, and 84 g) and the reduction in LDL-C levels is .63. Therefore, our data support the β-glucan hypothesis more than the substitution hypothesis. In addition, the

SummaryThe metabolic demands and synthetic capacity of the lactating mammary gland exceed that of any other tissue, thereby providing a useful paradigm for understanding the developmental regulation of cellular metabolism. By evaluating mice bearing targeted deletions in Akt1 or Akt2, we demonstrate that Akt1 is specifically required for lactating mice to synthesize sufficient quantities of milk to support their offspring. Whereas cellular proliferation, differentiation, and apoptosis are unaffected, loss of Akt1 disrupts the coordinate regulation of metabolic pathways that normally occurs at the onset of lactation. This results in a failure to upregulate glucose uptake, Glut1 surface localization, lipid synthesis, and multiple lipogenic enzymes, as well as a failure to downregulate lipid catabolic enzymes. These findings demonstrate that Akt1 is required in an isoform-specific manner for orchestrating many of the developmental changes in cellular metabolism that occur at the onset of lactation and establish a role for Akt1 in glucose metabolism.

Activation of the mouse c-myb oncogene in Abelson virus-induced plasmacytoid lymphosarcomas was studied using cDNA cloning and nucleotide sequence analysis. The results presented here show that viral integration in the myb locus generates splicing errors at the 5' and 3' regions. Viral integration results in transcriptional initiation within the viral long terminal repeat and generation of a chimeric mRNA that lacks the first three coding exons. The alterations at the 3' end are caused by an aberrant splicing event in which additional splice-donor and -acceptor sequences within intronic sequences are used to splice an additional 363 nucleotides into the myb transcripts. The resulting insertion of 121 amino acids is in a region of the protein where other activated forms of the myb gene product have deletions. These results suggest that alterations in the 3' end of the myb gene play a crucial role in the activation of this gene.