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A 50-year-old Nigerian woman presented to the infectious diseases clinic for evaluation of incidental left foot mass [...]

The glitazone class of insulin-sensitizing agents act, in part, by the activation of peroxisome proliferator-activated receptor (PPAR)-γ in adipocytes. However, it is unclear whether the expression of PPARγ in the islets is essential for their potential β-cell-sparing properties. To investigate the in vivo effects of rosiglitazone on β-cell biology, we used an inducible, pancreatic and duodenal homeobox-1 enhancer element-driven, Cre recombinase to knockout PPARγ expression specifically in adult β-cells (PPARgKO). Subjecting the PPARgKO mice to a chow diet led to virtually undetectable changes in glucose or insulin sensitivity, which was paralleled by minimal changes in islet gene expression. Similarly, challenging the mutant mice with a high-fat diet and treatment with rosiglitazone did not alter insulin sensitivity, glucose-stimulated insulin secretion, islet size, or proliferation in the knockout mice despite PPARγ-dependent and -independent changes in islet gene expression. These data suggest that PPARγ expression in the β-cells is unlikely to be directly essential for normal β-cell function or the insulin-sensitizing actions of rosiglitazone.

Observations at regular intervals of the location of newly hatched grape root borer, Vitacea polistiformis (Harris), larvae moving freely within circular petri dish bioassays were used to measure and compare their response to dry filter paper discs treated with ethanol- or hexane-based extracts of roots from known and potential Vitaceae hosts and a nonhost. Larvae responded most strongly to discs treated with ethanol extracts, suggesting the presence of behaviorally active, polar compounds associated with roots. In single extract bioassays comparing extract versus solvent treated discs, larvae responded positively to ethanol extracts from all Vitis species and rootstocks and Virginia creeper [Parthenocissus quinquefolia (L.) Planch.], but not to apple (Malus domestica Borkh). Paired extract bioassays, in which an extract from the commercially important 3309 rootstock was used as the standard and presented simultaneously with extracts from other root sources, revealed examples of equal, significantly weaker and significantly stronger responses to the 3309 extract. Extracts of the 420 A and V. riparia 'Gloire' rootstocks appeared to possess qualities that elicited a consistently greater response than to 3309 extract in these pair-wise comparisons. The active compounds were eluted in ethanol during a 30-min extraction; larvae responded equally to 30- and 60-min 3309 root extracts in paired extract bioassays. Larvae responded equally to extracts of 3309 roots from three spatially separate vineyards in northern Virginia. These results are discussed in relation to the subterranean, plant-insect interactions of grape root borer neonates with the numerous native and non-native Vitis species that may serve as hosts in the eastern United States.

OBJECTIVE A major determinant of the progression from insulin resistance to the development of overt type 2 diabetes is a failure to mount an appropriate compensatory β-cell hyperplastic response to maintain normoglycemia. We undertook the present study to directly explore the significance of the cell cycle protein cyclin D2 in the expansion of β-cell mass in two different models of insulin resistance. RESEARCH DESIGN AND METHODS We created compound knockouts by crossing mice deficient in cyclin D2 (D2KO) with either the insulin receptor substrate 1 knockout (IRS1KO) mice or the insulin receptor liver-specific knockout mice (LIRKO), neither of which develops overt diabetes on its own because of robust compensatory β-cell hyperplasia. We phenotyped the double knockouts and used RT-qPCR and immunohistochemistry to examine β-cell mass. RESULTS Both compound knockouts, D2KO/LIRKO and D2KO/IRS1KO, exhibited insulin resistance and hyperinsulinemia and an absence of compensatory β-cell hyperplasia. However, the diabetic D2KO/LIRKO group rapidly succumbed early compared with a relatively normal lifespan in the glucose-intolerant D2KO/IRS1KO mice. CONCLUSIONS This study provides direct genetic evidence that cyclin D2 is essential for the expansion of β-cell mass in response to a spectrum of insulin resistance and points to the cell-cycle protein as a potential therapeutic target that can be harnessed for preventing and curing type 2 diabetes.

Although dramatic amphibian population declines have been reported worldwide, our understanding of the extent of the declines in Latin America, where amphibian diversity is high, is limited to a few well-documented studies. To better understand the geographic extent of declines, their possible causes, and the measures needed to improve Latin American scientists' ability to research the phenomenon and make effective management recommendations, we convened three regional workshops with 88 Latin American herpetologists and conservationists. Population declines are widespread in Latin America. At least 13 countries have experienced declines, and in 40 cases species are now thought to be extinct or extirpated in a country where they once occurred. Declines or extinctions have affected 30 genera and nine families of amphibians. Most declines have occurred in remote highlands, above 500 m in elevation in Central America and above 1000 m in the Andes. Most documented declines occurred in the 1980s. Of the possible causes studied to date, climate change appears to be important at one site and chytrid fungal disease has been identified at sites in three countries. Although many monitoring studies are currently underway in a variety of habitats, most studies are recent and of short duration. In a signed resolution, workshop participants called for greater collaboration and communication among scientists working in Latin America to understand the geographic extent of population declines and the distribution of possible causal factors. In situ conservation is important to protect habitats, but captive-rearing programs for species subject to imminent extinction are also needed. Better understanding of the taxonomy and natural history of amphibians and more funding for research and monitoring are critical to developing a scientific basis for management action to arrest and reverse population declines.

The purpose of this essay is to stimulate academic discussion about the ethical justification of using human primordial stem cells for tissue transplantation, cell replacement, and gene therapy. There are intriguing alternatives to using embryos obtained from elective abortions and in vitro fertilisation to reconstitute damaged or dysfunctional human organs. These include the expansion and transplantation of latent adult progenitor cells.

It is argued that the use of induced pluripotent stem cells for regenerative therapy may soon be ethically practicable and could sidestep the various objections pertaining to other types of stem cell (human embryonic stem cells, and stem cells obtained by altered nuclear transfer or somatic cell nuclear transfer).

In two orchard experiments, interplanting wheat (Triticum aestivum cv. Stacy) around either newly planted or 4-year-old well-established peach trees did not suppress (P ≤ 0.05) the population density of the ring nematode, Criconemella xenoplax, after 3 years. Furthermore, inter-planting wheat around newly planted trees reduced tree growth, perhaps the result of competition for water and (or) nutrients. Wheat root exudate was not as attractive to C. xenoplax as peach root exudate, but wheat root exudate did not repel the nematode either. Stacy wheat appeared to be more beneficial as a preplant rather than as a postplant ground cover management tool for suppressing the population density of C. xenoplax.

Athanase a utilise une doctrine du salut qui combine la thematique du Nouvel Adam de Paul avec la reconciliation comme travail de Dieu en Jesus-Christ. Le sauveur elargit le pouvoir de Dieu a l'âme afin de transformer le chretien en enfant de Dieu. Cette transformation est interne et totalement dependante de l'incarnation du verbe de Dieu. De cette maniere, Athanase s'oppose a la theorie de la mediation d'Arius en affirmant que Jesus, en tant qu'homme, est le mediateur du salut. Pour Athanase, le chretien arrive au salut en repetant la mort du Christ a travers la pratique de la vertu

Virtually all industries are a product of their life and times or, more precisely, their history and the current economic environment within which they operate. Transportation is no exception. Significantly, both transport's history and its environment are driven by much the same fundamentals, each embodying a movement from quantity to quality. In fact, like so many other sectors of the economy, transportation is increasingly becoming a thinking person's business, with shorter technological and product life cycles, requiring increased ability to adapt quickly and flexibly.

Peach (Prunus persica L. Batsch. `Biscoe'/Lovell) trees were grown in a sandy loam soil under six orchard floor management systems, including five vegetative covers (continuous under the tree) and a vegetation-free control (bare ground). At the end of the fifth year, trees grown in bare ground and nimblewill grass (Muhlenbergia schreberi J.F. Gmel.) had a significantly larger trunk cross-sectional area (TCSA) than trees grown in weedy plots, centipedegrass [Eremochloa ophiuroides (Munro) Hack.], or bahiagrass (Paspalum notatum Flugge). Trees grown in brome (Bromus mollis L.) did not differ significantly in TCSA from any other treatment. Soil profile excavations of the root system revealed that trees grown in bare ground or with nimblewill had significantly higher root densities than those in the weedy plots or grown with bahiagrass. Vector analysis of root distribution indicated that trees grown in bare ground or nimblewill rooted deeper than trees in all other treatments. The greatest reduction in deep rooting occurred with bahiagrass.

Previous studies of shareholder rights plans (poison pills) have emphasized short-term valuation effects in the context of specific takeover attempts. This paper analyzes rights largely adopted in ‘neutral’ environments. Using a paired-case control approach, differences between rights and non-rights firms are examined. Positive long-term valuation effects are associated with restructurings, while negative performance is associated with ownership/control influences. The evidence supports a multiple signalling model in which investors use subsequent information to revise probabilities concerning control preferences of management and directors.

(2005). The Brave New World of Embryonic Stem Cell Research: Utilitarian Consequentialism and Faulty Moral Reasoning. The Linacre Quarterly: Vol. 72, No. 4, pp. 319-330.

Anicetus carolinensis Meyer (Hymenoptera: Encyrtidae) is proposed as the name of a new species found parasitizing terrapin scale, Mesolecanium nigrofasciatum (Pergande) (Hemiptera: Coccidae), in North Carolina. Both sexes are described and illustrated together with notes on the life history, host range, and reproductive behavior of the species.

Peach trees (`Biscoe'/Lovell) were planted in March, 1988 in ten different ground cover management systems. The trees were planted at the Sandhills Research Station in Southeastern North Carolina on a Candor sand and Eunola sandy loam. In December, 1991 the trench profile method was used to evaluate root distribution under the six orchard floor management systems of nimblewill, bare ground control, centipedegrass, brome, bahiagrass, and weedy control. Trenches were dug parallel to the tree row 60 cm from the center of the row on both sides of the tree. Grids 1 meter square, sectioned into 10 cm squares, were placed on the profile walls and root distribution (in three size categories) was recorded for 1 meter on each side of the tree in each trench. Root numbers were greatly reduced under the vegetative covers that provided the greatest suppression of vegetative tree growth. Total root densities under the trees in the vegetative covers were ranked into three size categories which were correlated with the amount of vegetative tree growth.

Dispersal of young was studied in a non-migratory population of the Black-capped Chickadee (Parus atricapillus) in southeastern Wisconsin. Eighty-eight chickadees were color-banded as nestlings. After fledging, the birds remained with their parents on or near the parental territory for about 3 weeks. In late June or early July family breakup occurred suddenly, with the young moving rapidly away. Most of the birds disappeared completely from the area; 6 were later discovered in the breeding population at distances of 0.4 to ca. 11 km, with a median dispersal distance of 1.1 km. This movement appeared to be an innate dispersal mechanism. In contrast, among 103 chickadees first trapped in July and early August as independent juveniles and later found on their breeding territories, the median distance from point where banded to territory was 204 m (maximum = 1,160 m). As distances up to 2.4 km could have been detected in our study area, we conclude that by late July and August chickadees have virtually finished dispersing and are developing site tenacity in the places where they will subsequently breed. Whether dispersal also occurs in spring was investigated using the monthly patterns of arrivals and disappearances from winter feeders. Adults and summer-banded juveniles inhabiting the parts of the study area nearest the feeders arrived for the first time at the feeders in November and December, but birds from more remote areas continued to arrive through the winter and spring. In previously unbanded juveniles there was an increase in arrivals in March and April. On the basis of an analysis of loss rates by sex and age, we conclude that only about 5% of yearling males and 9% of yearling females undertake some dispersal or spacing movements in spring. Thus, in the Black-capped Chickadee the main dispersal mechanism is an innate, rapid, fairly long-distance movement of the juvenile, taking place in summer just after family breakup. A small fraction of the yearling population undertakes some dispersal movement in the winter or spring.

OVER THE PAST FIVE YEARS, American corporations have taken aftertax writeoffs of over $10 billion dollars from discontinued operations and reductions in the book value of assets. During 1985 alone, over $5.6 billion in writedowns were recorded. If the sheer size of this restructuring is stunning, so too is the speed at which this practice has grown. According to COMPUSTAT data, aggregate writeoffs for all corporations totaled only $400 million in 1980.1 This practice of writing down assets has been widely heralded by the financial media. However, with the exception of a few papers on the effects of spinoffs and divestitures,2 there has been little research on the writedown decision and its effect on security values. This paper is divided into six sections. The first section describes how the substantial flexibility accorded by current accounting standards shapes managerial incentives to concentrate writeoffs and establish large reserves with probability of subsequent reversal. The second section discusses capital budgeting aspects of asset writedowns. To understand how the operating and financial environment influences the writedown decision, the third section analyzes the ex ante financial performance (relative to their respective industries) of a sample of 120 firms which announced writedowns between 1981 and 1985. Part four employs multiple discriminant analysis using a paired case control sample to study the determinants of writedowns. The fifth section uses event study methodology to analyze the effects of 78 writedown announcements on shareholder wealth. In addition, effects on the value of senior securities are examined. The final section summarizes the findings.

One hundred patients irradiated for cancers of the oral cavity, oropharynx, and nasopharynx were evaluated for the occurrence of osteonecrosis and associated predisposing factors. Selection was based on availability of complete dental records, a minimum of six months follow-up, and treatment fields, which included maxilla and/or mandible. Bone doses were calculated by using radiotherapy treatment records, port films, and isodose distributions. Osteonecrosis developed in 19 of 78 dentulous patients and in 3 of 22 edentulous patients. The time of development of osteonecrosis varied; in 15 cases osteonecrosis occurred more than one year after treatment. The most important risk factor for the development of osteonecrosis was the radiation dose to bone, particularly in the less vascular mandible. Osteonecrosis 7500 rads to the bone. None of the patients who received less than 6500 rads developed osteonecrosis. The risk was significantly greater when teeth were removed after therapy compared with those individuals with extractions before radiation or no extractions at all.

This paper is an attempt to examine critically the function of theory in historical research and particularly in economic history. the function of We shall take as our starting point the assertion that the historian is not interested simply in collecting facts or true statements about some segment of previous experience. He wants to find causes and to explain what happened. The purpose of this paper is to introduce some of the problems attached to the concepts of historical causality and explanation in a stochastic universe and to suggest how the analytic tools of scientific inference can be applied in economic historiography.