Chondrocytic and pharmacokinetic properties of Phlpp inhibitors.

Objective: The pleckstrin homology domain leucine-rich repeat protein phosphatases (Phlpp1/2) were recently identified as potential therapeutic targets for cartilage regeneration in osteoarthritic joints. Phlpp inhibitors NSC 117079 and NSC 45586 increase chondrocyte proliferation and matrix production, but the pharmacodynamics and pharmacokinetics of these compounds are not known. Design: Chondrocytic effects of Phlpp inhibitors, NSC 117079 and NSC 45586, were measured by western blotting of Phlpp substrates, glycosaminoglycan (GAG) assays, and transcriptomic assays. Liquid chromatography/mass spectroscopy assays were established to measure NSC 117079 and NSC 45586 in vitro and in vivo. The effects of NSC 117079 and NSC 45586 on articular cartilage structure in vivo after intra-articular injection were determined by histology. Results: The Phlpp inhibitors NSC 117079 and NSC 45586 were highly stable in vitro and stimulated GAG, Sox9, proteoglycan 4 and collagen 2 production in maturing but not more differentiated chondrocytes in vitro. Both molecules reduced Phlpp1/2 levels and suppressed matrix degradation to functionally extend their inhibitory effect on these phosphatases. In vivo, NSC 117079 was eliminated from the bloodstream within 4 â€‹h after intravenous injection, while NSC 45586 was eliminated in 8 â€‹h and had a higher volume distribution. Both molecules increased articular cartilage area on lateral and medial tibial plateaus and femoral condyles by 15% in C57Bl/6 mice between four and five weeks of age. Conclusion: These data advance our understanding of how Phlpp inhibitors promote and preserve cartilage formation and provide a basis for understanding their safety and activity in vivo.

Direct Measurement of Single-Molecule Ligand-Receptor Interactions.

Measuring the kinetics that govern ligand-receptor interactions is fundamental to our understanding of pharmacology. For ligand-gated ion channels, binding of an agonist triggers allosteric motions that open an integral ion-permeable pore. By mathematically modeling stochastic electrophysiological responses with high temporal resolution (ms), previous single channel studies have been able to infer the rate constants of ligands binding to these receptors. However, there are no reports of the direct measurement of the single-molecule binding events that are vital to how agonists exert their functional effects. For the first time, we report these direct measurements, the rate constants, and corresponding free energy changes, which describe the transitions between the different binding states. To achieve this, we use the super resolution technique: points accumulation for imaging in nanoscale topography (PAINT) to observe binding of ATP to orthosteric binding sites on the P2X1 receptor. Furthermore, an analysis of time-resolved single-molecule interactions is used to measure elementary rate constants and thermodynamic forces that drive the allosteric motions. These single-molecule measurements unequivocally establish the location of each binding states of the P2X1 receptor and the stochastic nature of the interaction with its native ligand. The analysis leads to the measurement of the forward and reverse rates from a weak ligand-binding state to a strong ligand binding state that is linked to allosteric motion and ion pore formation. These rates (kα = 1.41 sec-1 and kß = 0.32 sec-1) were then used to determine the free energy associated with this critical mechanistic step (3.7 kJ/mol). Importantly, the described methods can be readily applied to all ligand-gated ion channels, and more broadly to the molecular interactions of other classes of membrane proteins.

Permian polar forests: deciduousness and environmental variation.

Forests are expected to expand into northern polar latitudes in the next century. However, the impact of forests at high latitudes on climate and terrestrial biogeochemical cycling is poorly understood because such forests cannot be studied in the modern. This study presents forestry and geochemical analyses of three in situ fossil forests from Late Permian strata of Antarctica, which grew at polar latitudes. Stem size measurements and stump spacing measurements indicate significant differences in forest density and canopy structure that are related to the local depositional setting. For forests closest to fluvial systems, tree density appears to decrease as the forests mature, which is the opposite trend of self-thinning observed in modern forests. We speculate that a combination of tree mortality and high disturbance created low-density mature forests without understory vegetation near Late Permian river systems. Stable carbon isotopes measured from permineralized wood in these forests demonstrate two important points: (i) recently developed techniques of high-resolution carbon isotope studies of wood and mummified wood can be applied to permineralized wood, for which much of the original organic matter has been lost and (ii) that the fossil trees maintained a deciduous habit at polar latitudes during the Late Permian. The combination of paleobotanical, sedimentologic, and paleoforestry techniques provides an unrivaled examination of the function of polar forests in deep time; and the carbon isotope geochemistry supplements this work with subannual records of carbon fixation that allows for the quantitative analysis of deciduous versus evergreen habits and environmental parameters, for example, relative humidity.

Combination of flavor enhancement and chemosensory education improves nutritional status in older cancer patients.

BACKGROUND: Abnormalities in taste and smell functioning occur with elevated frequency in both older adults and patients with cancer. With the predicted increase in both of these populations in the coming decades, it is imperative to evaluate potential interventions that are designed to help older cancer patients compensate for the additive burden of this disease and its treatment on age-related taste and smell losses. OBJECTIVE: The purpose of the current study was to determine if providing instruction and products for flavor enhancement of foods to elderly cancer patients in addition to nutritional information would improve their nutritional status, and, by extension, functional and immune status as well as quality of life. DESIGN: One hundred and seven subjects enrolled in the study. Fifty-four subjects were in the experimental group that received flavor enhancement plus nutritional information; fifty-three control subjects received only nutritional information. Subjects were evaluated 1 month, 3 months, and 8 months after beginning chemotherapy. At every session, subjects completed taste and smell assessments as well as questionnaires related to nutritional status, activities of daily living, and quality of life. Blood samples were also obtained to determine immune parameters. RESULTS: At the eight-month time point, experimental subjects had better scores on the mini nutritional assessment (MNA) and the physical function assessment of the quality of life questionnaire. Also at eight months, self-reported taste and smell perception for experimental subjects was better than that of controls as well as better than at earlier time points. Tests that assessed quantity and quality of food intake, as well as a number of immune parameters declined over time and did not differ significantly between groups. CONCLUSION: The combination of flavor enhancement, chemosensory education, and nutritional information for elderly cancer patients improved their nutritional assessment on the MNA and physical function over time. On the whole, experimental subjects perceived themselves to be better functioning at eight months than did their control counterparts.

Stability and convergent validity of the Physical Activity Scale for the Elderly (PASE).

AIM: The purpose of this study was to assess the stability and convergent validity of the Physical Activity Scale for the Elderly (PASE) among rural, community dwelling elderly persons using Computer Science and Applications, Inc. Actigraph Monitors (Actigraph) as the direct criterion measure. EXPERIMENTAL DESIGN: a correlational design was employed. SETTING: rural community in the United States. PARTICIPANTS: 56 subjects (age=75.7+/-7.9 years) who were living independently and volunteered to participate in the study. MEASURES: subjects wore an Actigraph monitor during all waking hours for 7 consecutive days. At the conclusion of the 7 days, each subject met with a trained interviewer to complete the PASE questionnaire. Three days later the subjects met with the same interviewer to complete the PASE a 2nd time recalling their physical activity for the same 7-day period. RESULTS: Actigraph data indicated that subjects averaged 168.1+/-76.3 counts x minute(-1) during the 7-day period. A high intraclass correlation coefficient (r=0.91) was calculated between the 1st interview total PASE score (115.97+/-59.91) and the 2nd interview total PASE score (115.71+/-50.97). In addition, there was a statistically significant Spearman correlation coefficient of 0.43 (p<0.01) between Actigraph mean counts x minute(-1) and 1st interview total PASE scores. CONCLUSION: In this rural elderly sample, the PASE was a stable instrument with validity indices similar to those previously reported in younger, more active, populations.

Nitric oxide: a key regulator of myeloid inflammatory cell apoptosis.

Apoptosis of inflammatory cells is a critical event in the resolution of inflammation, as failure to undergo this form of cell death leads to increased tissue damage and exacerbation of the inflammatory response. Many factors are able to influence the rate of apoptosis in neutrophils, eosinophils, monocytes and macrophages. Among these is the signalling molecule nitric oxide (NO), which possesses both anti- and proapoptotic properties, depending on the concentration and flux of NO, and also the source from which NO is derived. This review summarises the differential effects of NO on inflammatory cell apoptosis and outlines potential mechanisms that have been proposed to explain such actions.

The advantages of aminolevulinic acid photodynamic therapy in dermatology.

Photodynamic therapy (PDT) is being increasingly employed in the detection and treatment of malignant and non-malignant disease. This local technique uses a photosensitizing drug activated by light to generate cell death via the production of reactive oxygen species. This review describes the fundamental processes behind PDT, focussing on the use of 5-aminolevulinic acid (ALA). ALA itself is not a photosensitizing drug, but administration of exogenous ALA induces the build-up of the natural endogenous photosensitizer protoporphyrin IX (PpIX). This form of PDT has proved promising for the treatment of a number of dermatological indications. An overview of these current and potential applications of ALA-based PDT is presented, with emphasis on the advantages of the technique that make it especially suitable for skin conditions and the problem areas on which future research should be focussed.

An unusual, structurally preserved ovule from the Permian of Antarctica.

Anatomically preserved ovules are described from silicified peat of Late Permian age collected from Skaar Ridge in the central Transantarctic Mountains, Antarctica. The small ovules are significant in possessing fleshy apical appendages and a funnel-shaped micropylar extension formed by the sarcotestal layer of the integument, by which they differ from all other Permian ovules described to date. The apical modifications may have functioned in pollination and/or seed dispersal. Similarity with the apical organization of earlier Paleozoic ovules is shown to be superficial, since the analogous structures are developmentally derived from different tissues. Although the ovules occur in rocks in which glossopterids are the only gymnosperms represented, there is insufficient evidence to assign them to a taxonomic group. These ovules are of particular importance because there are so few anatomically preserved gymnosperm reproductive structures known from the Permian and thus provide new data on the diversity of late Paleozoic gymnosperms.

Dissociation of DNA fragmentation from other hallmarks of apoptosis in nitric oxide-treated neutrophils: differences between individual nitric oxide donor drugs.

The events of apoptotic cell death can be experimentally dissociated from each other in certain cell types. Here we demonstrate the ability of structurally diverse nitric oxide (NO) donating compounds to delay or enhance neutrophil apoptosis and to differentially influence distinct parameters of programmed cell death. We provide evidence that high concentrations of the NO donors GEA 3162, SPER/NO, and DEA/NO induce morphological and biochemical markers of neutrophil apoptosis, but that only DEA/NO causes a concomitant increase in DNA fragmentation as evidenced by nuclear propidium iodide intercalation and the classical laddering pattern of electrophoresed DNA. In contrast, both GEA 3162 and SPER/NO inhibit DNA cleavage in a time- and concentration-dependent manner. We are the first to show that DNA fragmentation can be dissociated from other changes of apoptosis in NO-treated neutrophils and that it may therefore be inappropriate to assess NO-induced apoptosis solely by measuring DNA fragmentation in this cell type.

Cuticles of Mariopteris occidentalis White nov. emend. from the Middle Pennsylvanian of Oklahoma (USA), and a new type of climber hook for mariopteroid pteridosperms.

Cuticles of Mariopteris occidentalis are described from the Desmoinesian (Middle Pennsylvanian) of Oklahoma (USA). This species, like other mariopteroids, had a vine- to liana-like growth habit and climbed with specialized climber hooks. However, M. occidentalis is different from other mariopteroids in having small recurved hooks on the abaxial surfaces of the pinna axes. The diagnosis for M. occidentalis White 1899 is emended based on additional macroscopical observations and data on the epidermal anatomy; a lectotype is designated. M. occidentalis is compared with Pseudomariopteris cordato-ovata from the Stephanian and Autunian of Europe and North America, a taxon which is considered very similar and may be related. Although the two taxa indeed display similarities, significant evidence for a closer relationship could not be found. Finally, some features, e.g. marginal water pits and the stomatal structure, are considered with regard to their palaeoautecological significance where they are interpreted as adaptations to special physiological requirements of a vine- to liana-like life form.

Reconstruction of Pseudomariopteris busquetii, a vine-like Late Carboniferous-Early Permian pteridosperm.

The growth habit of the Late Carboniferous-Early Permian pteridosperm Pseudomariopteris busquetii is reconstructed based on compression material from the upper Stephanian of the Blanzy-Montceau and Commentry Basins (Massif Central, France), and the upper Rotliegend of the Saar-Nahe Basin (Nahe Group, N 4, Rheinland Pfalz, Germany). Pseudomariopteris busquetii was a medium-sized, vine- to liana-like plant with slender stems to which small bipartite fronds were attached. What is most interesting is that the species used at least two different strategies to both anchor and support the plant body. Most specimens possess specialized climber hooks developed from apical extensions of the pinna axes, indicating that the fronds were used to attach the plant. A few specimens suggest that the stem may also have had some capacity for attachment. In the absence of suitable supports, however, P. busquetii was apparently able to grow in dense stands or thickets in which the individual plants supported each other.

Effects of intravenous administration of formaldehyde on platelet and coagulation variables in healthy horses.

OBJECTIVES: To assess safety and determine effects of IV administration of formaldehyde on hemostatic variables in healthy horses. ANIMALS: 7 healthy adult horses. PROCEDURE: Clinical signs and results of CBC, serum biochemical analyses, and coagulation testing including template bleeding time (TBT) and activated clotting time (ACT) were compared in horses given a dose of 0.37% formaldehyde or lactated Ringer's solution (LRS), IV, in a 2-way crossover design. In a subsequent experiment, horses received an infusion of 0.74% formaldehyde or LRS. In another experiment, horses were treated with aspirin to impair platelet responses prior to infusion of formaldehyde or LRS. RESULTS: Significant differences were not detected in any variable measured between horses when given formaldehyde or any other treatment. Infusion of higher doses of formaldehyde resulted in adverse effects including muscle fasciculations, tachycardia, tachypnea, serous ocular and nasal discharge, agitation, and restlessness. CONCLUSIONS AND CLINICAL RELEVANCE: Intravenous infusion of formaldehyde at doses that do not induce adverse reactions did not have a detectable effect on measured hemostatic variables in healthy horses.

New perspectives on the Mesozoic seed fern order Corystospermales based on attached organs from the Triassic of Antarctica.

A new Triassic corystosperm is described from the Shackleton Glacier region of Antarctica. The compression fossils include cupulate organs (Umkomasia uniramia) and leaves (Dicroidium odontopteroides) attached to short shoot-bearing branches. The cupulate organs occur in groups near the apices of the short shoots, and each consists of a single axis with a pair of bracts and a subapical whorl of five to eight ovoid cupules. This unique architecture indicates that the cupules are individual megasporophylls rather than leaflets of a compound megasporophyll. A branch bearing an attached D. odontopteroides leaf provides the first unequivocal evidence that Umkomasia cupulate organs and Dicroidium leaves were produced by the same plants. Although this had previously been assumed based on organ associations, the new specimens are important in demonstrating that a single species of corystosperm produced the unique cupulate organs described here and the geographically and stratigraphically widespread and common D. odontopteroides leaf. Therefore, biostratigraphic, paleoecological, and phylogenetic studies that treat Dicroidium leaf morphospecies as proxies for biological species of entire plants should be reconsidered. Phylogenetic analysis suggests that the corystosperm cupule is an unlikely homologue for the angiosperm carpel or outer integument.

Paleoazolla, a new heterosporous fern from the Upper Cretaceous of Argentina.

Megaspore and microspore massulae of Paleoazolla patagonica gen. et sp. nov. are described from the Upper Cretaceous of La Colonia Formation, Chubut Province, Argentina. The new fern possesses megaspore complexes with three to four glochidiate floats attached directly to the megaspore; a columella-like structure appears to be absent. The megaspore wall consists of a two-layered exine that is smooth to irregularly perforate, a two-layered perine with a spongy, densely packed endoperine, and a loosely organized exoperine. Infrafilosum hairs cover the exoperine. Microspore massulae are irregular in size and shape and bear multibarbed glochidia that generally have anchor-shaped tips. A comparison with other azollaceous and salviniaceous genera, particularly Azolla, is provided, together with a discussion of some evolutionary trends within the family.

The gynecologist and the prevention of cardiovascular disease.

This article reviews current concepts regarding the prevention of cardiovascular disease for women, with particular attention to modifiable risk factors. The background describes the magnitude of the problem, assesses the quality of the data with respect to risk factor reduction, and emphasizes several important concepts. Changes at menopause, states of endocrine aberration, and benefits and risks of hormone substitution need to be understood in conjunction with all other potentially modifiable and nonmodifiable cardiovascular risk factors. Primary care physicians have a window of opportunity to prevent this number one women's health problem. Integrating behavior modification is the key to prevention as part of the regular gynecologic visit.

The gynecologist and cardiovascular disease: a window of opportunity for prevention.

OBJECTIVE: We present current concepts and assess the quality of information available for the prevention of cardiovascular disease in women. METHODS: This article reviews research bearing on the prevention of cardiovascular disease in women, with particular attention to modifiable risk factors. We describe the magnitude of the problem and assess the quality of the data with respect to the classic risk factors. The concept is emphasized that changes at menopause, states of endocrine aberration, and benefits and risks of hormone substitution and oral contraception must be understood in conjunction with all other potentially modifiable and nonmodifiable risk factors. CONCLUSIONS: Primary care physicians, especially obstetrician/gynecologists, have a pivotal role to play in the reduction of this disease. Behavior modification is the key to integrating prevention into the regular annual visit.