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Kinds of Studies Point Selected AbstractsStructural Diversity of PDZ,Lipid InteractionsCHEMBIOCHEM, Issue 4 2010Rodrigo Gallardo Abstract PDZ domains are globular protein modules that are over-and-above appreciated for their interaction with short peptide motifs found in the cytosolic tail of membrane receptors, channels, and adhesion molecules. These domains predominate in scaffold molecules that control the assembly and the location of large signaling complexes. Studies have now emerged showing that PDZ domains can also interact with membrane lipids, and in particular with phosphoinositides. Phosphoinositides control various aspects of cell signaling, vesicular trafficking, and cytoskeleton remodeling. When investigated, lipid binding appears to be extremely relevant for PDZ protein functionality. Studies point to more than one mechanism for PDZ domains to associate with lipids. Few studies have been focused on the structural basis of PDZ,phosphoinositide interactions, and the biological consequences of such interactions. Using the current knowledge on syntenin-1, syntenin-2, PTP-Bas, PAR-3 and PICK1, we recapitulate our understanding of the structural and biochemical aspects of PDZ,lipid interactions and the consequences for peptide interactions. [source] DOES CRIME JUST MOVE AROUND THE CORNER?CRIMINOLOGY, Issue 3 2006A CONTROLLED STUDY OF SPATIAL DISPLACEMENT AND DIFFUSION OF CRIME CONTROL BENEFITS Recent studies point to the potential theoretical and practical benefits of focusing police resources on crime hot spots. However, many scholars have noted that such approaches risk displacing crime or disorder to other places where programs are not in place. Although much attention has been paid to the idea of displacement, methodological problems associated with measuring it have often been overlooked. We try to fill these gaps in measurement and understanding of displacement and the related phenomenon of diffusion of crime control benefits. Our main focus is on immediate spatial displacement or diffusion of crime to areas near the targeted sites of an intervention. Do focused crime prevention efforts at places simply result in a movement of offenders to areas nearby targeted sites,"do they simply move crime around the corner"? Or, conversely, will a crime prevention effort focusing on specific places lead to improvement in areas nearby,what has come to be termed a diffusion of crime control benefits? Our data are drawn from a controlled study of displacement and diffusion in Jersey City, New Jersey. Two sites with substantial street-level crime and disorder were targeted and carefully monitored during an experimental period. Two neighboring areas were selected as "catchment areas" from which to assess immediate spatial displacement or diffusion. Intensive police interventions were applied to each target site but not to the catchment areas. More than 6,000 20-minute social observations were conducted in the target and catchment areas. They were supplemented by interviews and ethnographic field observations. Our findings indicate that, at least for crime markets involving drugs and prostitution, crime does not simply move around the corner. Indeed, this study supports the position that the most likely outcome of such focused crime prevention efforts is a diffusion of crime control benefits to nearby areas. [source] Hodgkin's lymphoma: Diagnostic difficulties in fine-needle aspiration cytologyDIAGNOSTIC CYTOPATHOLOGY, Issue 8 2009D.Sc., Dilip K. Das M.B.B.S., F.R.C.Path., Ph.D. Abstract It is commonly believed that cytodiagnosis of Hodgkin's lymphoma (HL) is much easier than that of non-Hodgkin lymphoma (NHL). However, recognition of certain NHL subtypes with Reed-Sternberg (R-S)-like cells and results of immunohistochemical studies point to the contrary. To study the limitations of cytology in diagnosis of HL, fine-needle aspiration (FNA) smears of 130 lymphoma or suspected lymphoma cases were reviewed. Initial and reviewed cytodiagnoses were compared with histopathology in 89 cases. Immunocytochemical and immunohistochemical studies were performed in 56 and 59 cases, respectively. Among histologically diagnosed HL cases, definitive cytodiagnosis of HL (initial as well as reviewed) was significantly less frequent than cytodiagnosis of NHL among histologically diagnosed NHL cases (P = 0.0328 and = 0.0001, respectively). On the other hand, cytologically diagnosed HL/NHL cases were significantly more frequent in the former group (P = 0.0001 and = 0.0018, respectively). ALCL and TCRBCL were the two NHL subtypes which created confusion with HL in FNA smears. Twenty-one cytohistological concordant HL cases and equal number of discordant cases were compared. When compared with discordant group, the patients in concordant group were significantly younger (P = 0.045). Hodgkin/Hodgkin-like cells and typical R-S cells were significantly more frequent in FNA smears of the concordant group (P = 0.0478 and = 0.0431, respectively). Immunocytochemical and immunohistochemical studies showed good correlation with histological diagnosis of HL. It is suggested that proper interpretation of cytologic features, together with use of immunocytochemical parameters can help in reducing the margin of error in cytodiagnois of HL. Diagn. Cytopathol. 2009. © 2009 Wiley-Liss, Inc. [source] Suppressing the Anionic Fries Rearrangement of Aryl Dialkylcarbamates; the Isolation of a Crystalline ortho -Deprotonated CarbamateEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 4 2008Felipe García Abstract In the presence of organolithium bases phenyl dialkylcarbamates have previously been shown to undergo facile rearrangement to yield the corresponding salicylamides. However, heterometallic lithium diethyl(2,2,6,6-tetramethylpiperidido)zincate achieves the clean directed ortho -metallation (DoM) of phenyl dialkylcarbamates, with [C6H4{OC(O)NMe2}{Zn(-TMP)Et}Li]2 having been structurally characterized. DFT studies point to a stepwise deprotonative mechanism in which the zincate reagent exhibits kinetic amido basicity. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Elite Consensus as a Determinant of Alliance Cohesion: Why Public Opinion Hardly Matters for NATO-led Operations in AfghanistanFOREIGN POLICY ANALYSIS, Issue 3 2010Sarah Kreps Despite the increasing popularity of fighting wars through multilateral coalitions, scholars have largely been silent on the question of how public opinion in member states affects alliance cohesion. This article assesses public opinion data for states contributing to operations in Afghanistan. It finds that despite the unpopularity of the war, leaders have largely bucked public opinion and neither reduced nor withdrawn troops from NATO-led operations in Afghanistan. Theoretical expectations about international cooperation and evidence from case studies point to elite consensus as the reason why leaders are not running for the exits in Afghanistan when their publics would prefer that they do. As the article shows, operating through a formal institution such as NATO creates systemic incentives for sustained international cooperation. The result is that elite consensus inoculates leaders from electoral punishment and gives states' commitments to Afghanistan a "stickiness" that defies negative public opinion. A formal alliance such as NATO may therefore create more policy constraints than an ad hoc coalition but also increase the costs of defection and confer a degree of staying power that is unexpected given the adverse public opinion environment. [source] Biasing the organism for novelty: A pervasive property of the attention systemHUMAN BRAIN MAPPING, Issue 8 2010Qi Chen Abstract Although the functional and anatomical independences between the orienting and the executive attention networks have been well established, surprisingly little is known about the potential neural interaction between them. Recent studies point out that spatial inhibition of return (IOR), a mechanism associated with the orienting network, and nonspatial inhibition of return, a mechanism associated with the executive network, might bias the organism for novel locations and objects, respectively. By orthogonally combining the spatial and the nonspatial IOR paradigms in this fMRI study, we demonstrate that the orienting and the executive networks interact and compensate each other in biasing the attention system for novelty. Behaviorally, participants responded slower to the target at the old location only when the color of the target was novel, and participants responded slower to the old color representation only when the target appeared at a novel spatial location. Neurally, the orienting network was involved in slowing down responses to the old location only when the nonspatial IOR mechanism in the executive network was not operative (i.e., when the color of the target was novel); the prefrontal executive network was involved in slowing down responses to the old color representation only when the spatial IOR mechanism in the orienting network was not functioning (i.e., when the target appeared at a novel location). Hum Brain Mapp, 2010. © 2010 Wiley-Liss, Inc. [source] Increasing Dietary Protein Requirements in Elderly People for Optimal Muscle and Bone HealthJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 6 2009Erin Gaffney-Stomberg MS Osteoporosis and sarcopenia are degenerative diseases frequently associated with aging. The loss of bone and muscle results in significant morbidity, so preventing or attenuating osteoporosis and sarcopenia is an important public health goal. Dietary protein is crucial for development of bone and muscle, and recent evidence suggests that increasing dietary protein above the current Recommended Dietary Allowance (RDA) may help maintain bone and muscle mass in older individuals. Several epidemiological and clinical studies point to a salutary effect of protein intakes above the current RDA (0.8 g/kg per day) for adults aged 19 and older. There is evidence that the anabolic response of muscle to dietary protein is attenuated in elderly people, and as a result, the amount of protein needed to achieve anabolism is greater. Dietary protein also increases circulating insulin-like growth factor, which has anabolic effects on muscle and bone. Furthermore, increasing dietary protein increases calcium absorption, which could be anabolic for bone. Available evidence supports a beneficial effect of short-term protein intakes up to 1.6 to 1.8 g/kg per day, although long-term studies are needed to show safety and efficacy. Future studies should employ functional measures indicative of protein adequacy, as well as measures of muscle protein synthesis and maintenance of muscle and bone tissue, to determine the optimal level of dietary protein. Given the available data, increasing the RDA for older individuals to 1.0 to 1.2 g/kg per day would maintain normal calcium metabolism and nitrogen balance without affecting renal function and may represent a compromise while longer-term protein supplement trials are pending. J Am Geriatr Soc 57:1073,1079, 2009. [source] Changing the pathogenetic roadmap of liver fibrosis?JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 7pt1 2008Where did it start; where will it go? Abstract The pathophysiology of liver injury has attracted the interest of experimentalists and clinicians over many centuries. With the discovery of liver-specific pericytes , formerly called fat-storing cells, Ito-cells, lipocytes, and currently designated as hepatic stellate cells (HSC) , the insight into the cellular and molecular pathobiology of liver fibrosis has evolved and the pivotal role of HSC as a precursor cell-type for extracellular matrix,producing myofibroblasts has been established. Although activation and transdifferentiation of HSC to myofibroblasts is still regarded as the pathogenetic key mechanism of fibrogenesis, recent studies point to a prominent heterogeneity of the origin of myofibroblasts. Currently, the generation of matrix-synthesizing fibroblasts by epithelial,mesenchymal transition, by influx of bone marrow,derived fibrocytes into damaged liver tissue, and by differentiation of circulating monocytes to fibroblasts after homing in the injured liver are discussed as important complementary mechanisms to enlarge the pool of (myo-)fibroblasts in the fibrosing liver. Among the molecular mediators, transforming growth factor-beta (TGF-,) plays a central role, which is controlled by the bone-morphogenetic protein (BMP)-7, an important antagonist of TGF-, action. The newly discovered pathways supplement the linear concept of HSC activation to myofibroblasts, point to fibrosis as a systemic response involving extrahepatic organs and reactions, add further evidence to a more or less uniform concept of organ fibrosis in general (e.g. liver, lung, kidney), and offer innovative approaches for the development of non-invasive biomarkers and antifibrotic trials. [source] Use of radiotherapy in the primary treatment of cancer in South AustraliaJOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 2 2003Colin Luke Summary Previous studies point to a lower use of radiotherapy by Australian cancer patients in lower socioeconomic areas and in country regions that are some distance from urban treatment centres. These were cross-sectional studies with the potential for error from changes in place of residence. We used a cohort design to avoid such error. South Australian patients diagnosed in 1990,1994 were followed until the date of censoring of 31 December 1999 using data from the State Cancer Registry. The percentage found to have had megavoltage therapy in the first 12 months following diagnosis varied by leading primary incidence site from 44% for the prostate to 40% for female breast, 38% for lung, 17% for rectum, 3% for colon and 2% for skin (melanoma). Multivariate analysis indicated that determinants of not receiving megavoltage therapy in the first 12 months were older age, female sex, residence in a country region and country of birth. Melanoma data revealed earlier stages for women than men. If this difference by sex applies to other cancers, it might explain the lower exposure of women to radiotherapy. Fewer older patients received radiotherapy, consistent with trends observed in hospital-based cancer-registry data. The influence on this finding of differences in stage and comorbidity requires additional study. While earlier findings of a lower exposure of country residents to radiotherapy were confirmed, the difference was comparatively small in this study. Variations in exposure by socioeconomic status of residential area were not observed. [source] The neuropathogenic contributions of lysosomal dysfunctionJOURNAL OF NEUROCHEMISTRY, Issue 3 2002Ben A. Bahr Abstract Multiple lines of evidence implicate lysosomes in a variety of pathogenic events that produce neurodegeneration. Genetic mutations that cause specific enzyme deficiencies account for more than 40 lysosomal storage disorders. These mostly pre-adult diseases are associated with abnormal brain development and mental retardation. Such disorders are characterized by intracellular deposition and protein aggregation, events also found in age-related neurodegenerative diseases including (i) Alzheimer's disease and related tauopathies (ii) Lewy body disorders and synucleinopathies such as Parkinson's disease, and (iii) Huntington's disease and other polyglutamine expansion disorders. Of particular interest for this review is evidence that alterations to the lysosomal system contribute to protein deposits associated with different types of age-related neurodegeneration. Lysosomes are in fact highly susceptible to free radical oxidative stress in the aging brain, leading to the gradual loss of their processing capacity over the lifespan of an individual. Several studies point to this lysosomal disturbance as being involved in amyloidogenic processing, formation of paired helical filaments, and the aggregation of ,-synuclein and mutant huntingtin proteins. Most notably, experimentally induced lysosomal dysfunction, both in vitro and in vivo, recapitulates important pathological features of age-related diseases including the link between protein deposition and synaptic loss. [source] The use of three different solid dispersion formulations,melt extrusion, film-coated beads, and a glass thermoplastic system,to improve the bioavailability of a novel microsomal triglyceride transfer protein inhibitorJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 5 2004Geert Verreck Abstract A bioavailable formulation for a water-insoluble microsomal triglyceride transfer protein inhibitor, R103757, was developed using solid dispersion technology. The need for an advanced formulation was tested in the dog by assessing the oral bioavailability of three generic concepts: a tablet (crystalline drug), a capsule (film-coated beads), and an oral solution. These screening studies steered further development in the direction of a solid dispersion. Three solid dispersion platforms were assessed: melt extrusion, film-coated beads, and a glass thermoplastic system. Thermal and spectrophotometric analysis revealed that no crystalline drug was present in any of the formulations. The dissolution profiles of the three dispersion systems showed that release was improved compared with the unmanipulated drug. In addition, stability studies confirmed the physical and chemical integrity of the formulation. A human clinical trial was performed to assess the pharmacokinetics of the three amorphous dispersions. Plasma levels were obtained after single oral administration in both the fasting and fed state. The study indicated that all three approaches improved the bioavailability of R103757 with the glass thermoplastic system providing the best performance. These studies point to the potential usefulness of solid dispersion approaches and expand the possible number of ways to implement these methodologies. © 2004 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 93:1217,1228, 2004 [source] Effects of lutein and zeaxanthin on aspects of eye healthJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2010Le Ma Abstract Lutein and zeaxanthin are members of the oxygenated carotenoids found particularly in egg yolks and dark-green leafy vegetables. A great deal of research has focused on their beneficial roles in eye health. The present article summarises the current literature related to the bioactivity of these carotenoids, emphasising their effects and possible mechanisms of action in relation to human eye health. Available evidence demonstrates that lutein and zeaxanthin are widely distributed in a number of body tissues and are uniquely concentrated in the retina and lens, indicating that each has a possible specific function in these two vital ocular tissues. Most of epidemiological studies and clinical trials support the notion that lutein and zeaxanthin have a potential role in the prevention and treatment of certain eye diseases such as age-related macular degeneration, cataract and retinitis pigmentosa. The biological mechanisms for the protective effects of these carotenoids may include powerful blue-light filtering activities and antioxidant properties. Although most studies point towards significant health benefits from lutein and zeaxanthin, further large-scale randomised supplementation trials are needed to define their effects on ocular function in health and disease. Copyright © 2009 Society of Chemical Industry [source] Prevalence of latex sensitization and allergy in Portuguese childrenPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 6 2006Arminda Jorge The prevalence of latex allergy has been increasing not only in risk groups but also in the general population, where it is accepted to average 1%. In children, latex sensitization prevalence studies are scarce and involve different population sampling and allergy testing methods, which makes it difficult to compare across studies. Nevertheless, existing studies point towards a low prevalence of latex allergy in children, which still needs to be confirmed in the Portuguese population. Aiming at studying the prevalence of latex sensitization and allergy in a sample of Portuguese children, we studied 182 children from two different hospital outpatient clinics. A standardized questionnaire focusing on atopic background, previous history and allergic signs or symptoms on exposure to latex or fruits was given to all children and parents. Skin prick testing was performed with a battery of common aeroallergens as well as latex. Serum total IgE, Phadiatop, F × 5E and latex-specific IgE were determined in all children. Specific IgE to latex-crossreacting fruits was determined in latex-sensitized children. Based upon the questionnaire, the prevalence of latex allergy would be 0.5%. The prevalence of latex sensitization would be 3.8%, when based solely upon skin prick testing, and 12.1% (,0.35 IU/ml) or 6.6% (,0.70 IU/ml) when based singly upon determination of latex-specific IgE. When positive results for either test were considered, the prevalence of latex sensitization was 14.3%. All latex-sensitized children were atopic. Sensitivity to latex-crossreacting foodstuffs was demonstrated in 61.5% of latex-sensitized children (16/26). This study shows that the prevalence of latex allergy and sensitization in Portuguese atopic and non-atopic children, as analysed using various diagnostic methods, is similar to that observed in other countries. In addition, the assessment of latex allergy and sensitization should always include skin prick testing and determination of serum IgE. [source] UV Exposure, Genetic Targets in Melanocytic Tumors and Transgenic Mouse Models,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 1 2005Frank R. de Gruijl ABSTRACT The genetic changes and corruption of kinase activity in melanomas appear to revolve around a central axis: mitogenic signaling along the RAS pathway down to transcription regulation by pRB. Epidemiological studies point to the importance of ultraviolet (UV) radiation in the etiology of melanoma, but where and how UV radiation is targeted to contribute to the oncogenic signaling remains obscure. Animal models of melanoma genesis could serve to clarify this issue, but many of these models are not responsive to UV exposure. Most interesting advances have been made by using transgenic mice that carry genetic defects that are known to be relevant to human melanoma: specifically, dysfunction in the tumor suppressive action of p161NK4a or a receptor tyrosine kinase/RAS pathway, that is constitutively activated in melanocytes. The latter types of mice appear to be most responsive to (neonatal) UV exposure. Whether this is due to a general increase in target cells by melanocytosis and a paucity or complete lack of pigment, or a possible UV-induced response of the promoter,enhancer of the transgene or a genuinely independent and additional genetic alteration caused by UV exposure needs to be established. Importantly, the full effect of UV radiation needs to be ascertained in mice with different pigmentation by varying the wavelengths, UV-B versus UV-A1, and the exposure schedules, i.e. neonatal versus adult and chronic versus intermittent overexposure. Intermittent UV-B overexposure deserves special attention because it most strongly evokes proliferative responses in melanocytes. [source] Gonadal steroids and salivary IgA in healthy young women and menAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2010Sari M. Van Anders Empirical evidence from clinical, nonhuman animal, and in vitro studies point to links between immune function and gonadal steroids, including potential androgenic immunosuppression and estrogenic immunoenhancement. This study was designed to test links between steroids and one marker of mucosal humoral immunity,immunoglobulin A (IgA) in healthy individuals, to facilitate comparisons with other species and clinical populations, as there are few existing studies with healthy humans that also allow gender/sex investigations. Participants (86 women, 91 men) provided a saliva sample for measurement of testosterone (T), estradiol (E2), and IgA. Results showed that E2 was significantly and positively correlated with IgA in women, and group analyses by E2 quartile showed that this association was linear. No significant correlations or nonlinear associations were seen between T and IgA in men or women, or E2 and IgA in men. Evidence from this study indicates that IgA and E2 are significantly associated in healthy premenopausal women. Am. J. Hum. Biol. 2010. © 2009 Wiley-Liss, Inc. [source] On the graphitisation role of oxide supports in carbon nanotube CVD synthesisPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 10 2008M. H. Rümmeli Abstract In this contribution we present various data from CNT grown from supported catalysts. The observed data are in agreement with the catalyst volume to surface area model developed for floating catalysts and which predicts a direct CNT diameter and number of wall dependence on the catalyst size. Further, our studies point to the root of a CNT lying at the support rather than the catalyst. Additional supporting studies point to oxygen playing a critical role in the growth of CNT, viz. the CNT can grow from an oxide support rather than the catalyst. In this scenario the catalysts role is twofold; to precipitate carbon from the catalyst,carbon eutectic upon supersaturation and thus form the embryonic caps and to form circular defect sites at its circumference on the oxide support. These circular defect sites enable continued CNT growth directly from the support. Our findings point to catalytic processes very reminiscent of many other heterogeneous catalytic processes. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Influence of depressed mood on neuropsychologic performance in HIV-seropositive drug usersPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 3 2003Enrique Vázquez-Justo Abstract Some studies point out that depression affects the performance of HIV patients in neuropsychological tasks, but at present this effect is not clear. The purpose of the present paper was to study whether the presence of symptoms of depression affects the neuropsychologic performance of seropositive drug users in tasks of attention/concentration, learning and memory, language, construction and visuospatial function, speed of motor performance, cognitive flexibility, manual skill and concept formation and reasoning. In order to carry out this research a sample consisting of 127 male volunteer subjects was used. These subjects were distributed in four groups: one group consisted of HIV-seropositive drug users with symptoms of depression (n = 33); the second group consisted of HIV-seropositive drug users without symptoms of depression (n = 47); the third group was formed by HIV-seronegative drug users with symptoms of depression (n = 15) and the fourth group was formed by HIV-seronegative drug users without symptoms of depression (n = 32). The results reveal the effect of symptoms of depression (evaluated by the Beck Depression Inventory) on the neuropsychologic performance of seropositive drug users. This effect, however, was not observed in the seronegative group. These findings lead us to suggest that symptoms of depression constitute a risk factor for presenting neuropsychologic disturbances in seropositive subjects, which could well be acting as a factor that foments the neuropsychological effects of HIV. [source] Transport of cytokinins mediated by purine transporters of the PUP family expressed in phloem, hydathodes, and pollen of ArabidopsisTHE PLANT JOURNAL, Issue 1 2003Lukas Bürkle Summary Nucleobases and derivatives like cytokinins and caffeine are translocated in the plant vascular system. Transport studies in cultured Arabidopsis cells indicate that adenine and cytokinin are transported by a common H+ -coupled high-affinity purine transport system. Transport properties are similar to that of Arabidopsis purine transporters AtPUP1 and 2. When expressed in yeast, AtPUP1 and 2 mediate energy-dependent high-affinity adenine uptake, whereas AtPUP3 activity was not detectable. Similar to the results from cell cultures, purine permeases (PUP) mediated uptake of adenine can be inhibited by cytokinins, indicating that cytokinins are transport substrates. Direct measurements demonstrate that AtPUP1 is capable of mediating uptake of radiolabeled trans -zeatin. Cytokinin uptake is strongly inhibited by adenine and isopentenyladenine but is poorly inhibited by 6-chloropurine. A number of physiological cytokinins including trans- and cis- zeatin are also efficient competitors for AtPUP2-mediated adenine uptake, suggesting that AtPUP2 is also able to mediate cytokinin transport. Furthermore, AtPUP1 mediates transport of caffeine and ribosylated purine derivatives in yeast. Promoter,reporter gene studies point towards AtPUP1 expression in the epithem of hydathodes and the stigma surface of siliques, suggesting a role in retrieval of cytokinins from xylem sap to prevent loss during guttation. The AtPUP2 promoter drives GUS reporter gene activity in the phloem of Arabidopsis leaves, indicating a role in long-distance transport of adenine and cytokinins. Promoter activity of AtPUP3 was only found in pollen. In summary, three closely related PUPs are differentially expressed in Arabidopsis and at least two PUPs have properties similar to the adenine and cytokinin transport system identified in Arabidopsis cell cultures. [source] Pseudo-placentational Endometrial Cysts in a BitchANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 1 2010C. Bartel Summary Cystic alterations of the canine endometrium compromise reproduction and fertility of the bitch and may lead to life-threatening diseases, such as pyometra. Even without clinical evidence, reduction of the uterine lumen by cysts implicates disturbances during migration, nidation and development of the embryo. Several studies point to the high variability of morphology of uterine endometrial cysts but they lack detailed analyses of alterations. In the present study, immunohistochemistry was used to investigate the expression of steroid hormone receptors (oestrogen, progesterone), proliferation activity, inflammation and infection in the cystic affected tissue regions in contrast to the normal endometrium. Oestrogen receptor expression showed a high density of receptors throughout the surface epithelial cells, crypt epithelial cells, glandular epithelial cells and stromal cells of the normal endometrium as well as the cystic affected regions. Proliferation in the cysts was verified in the middle and basal cells of the crypts. Neither in the endometrium nor in the cysts inflammatory processes or evidence of infection could be detected. Furthermore, lectin histochemistry and electron microscopic methods showed that lectin binding patterns and cell morphology of internal epithelial lining and surface epithelium of the cysts can be used to characterize and distinguish different types of cystic alterations. Analogies between epithelial cells of the glandular chambers of the canine placenta and the cystic cellular morphology, steroid hormone receptor distribution as well as lectin binding patterns of the endometrial cysts, as observed in this study, suggest to introduce the term ,pseudo-placentational endometrial cysts'. [source] 2124: Src family tyrosine kinase activation is required for endothelin-1 to inhibit Na,K-ATPase in porcine lens epitheliumACTA OPHTHALMOLOGICA, Issue 2010NA DELAMERE Purpose Earlier studies point to the involvement of Src family tyrosine kinases (SFKs) in the stimulation of of Na,K-ATPase activity by purinergic receptor agonists ATP and UTP. Src itself was activated (Tamiya, et al. 2007, Am. J. Physiol. 293: C790-6). Here, we examined the role of SFKs in the response to endothelin-1 (ET-1), an ET receptor agonist that causes Na,K-ATPase inhibition. Methods Porcine lenses were incubated 30 min in Krebs' solution with ET-1 or other test agents. The epithelium was removed, homogenized and analyzed by western blot or Na,K-ATPase activity assay. Results Exposure of the intact lens to ET-1 caused a reduction in Na,K-ATPase activity. The Na,K-ATPase response was not observed when lenses were pretreated with 10 uM PP2, a selective inhibitor of SFKs. ET-1 caused SFK activation evident from an increase in Y416 phosphorylation and decrease in Y527 phosphorylation of a ~61kDa SFK. The SFK inhibitor PP2 abolished the SFK phosphorylation response. Since SFKs Fyn, Src, Hck and Yes may contribute to the observed 61kDa band, these SFKs were isolated by immunoprecipitation and analyzed separately. Based on Y416 phosphorylation, ET-1 appeared to activate Fyn, while Src and Hck were inhibited. Yes activity was unaltered. Conclusion ET-1, which causes Na,K-ATPase inhibition, elicits a different pattern of SFK activation from that reported earlier for purinergic agonists which stimulate Na,K-ATPase activity. Previously, Na,K-ATPase stimulation was observed when Src was activated. The ET-1 response points to Na,K-ATPase inhibition when Fyn kinase is activated. [source] Testicular dysgenesis syndrome: foetal origin of adult reproductive problemsCLINICAL ENDOCRINOLOGY, Issue 4 2009Christine Wohlfahrt-Veje Summary The evidence for the existence of testicular dysgenesis syndrome (TDS) is presented in this review. Several epidemiological studies have shown that conditions like cryptorchidism, impaired spermatogenesis, hypospadias and testicular cancer can be associated as risk factors for each other. Thus, the risk of testis cancer is significantly increased in men with cryptorchidism and/or infertility. Several recent studies point towards early dysgenesis of the foetal testis as the biological link between these disorders. Dysgenesis has been demonstrated in biopsies of the contralateral testis of men with testis cancer and in infertile men. The histological evidence includes immature seminiferous tubules with undifferentiated Sertoli cells, microliths and Sertoli-cell only tubules. Dysgenetic testes often have an irregular ultrasound pattern, where microliths may also be visible. Our current hypothesis is that maternal exposure to endocrine disrupting chemicals may contribute to the pathogenesis of TDS. Animal experiments have shown that all TDS symptoms, except testicular cancer, can be induced by foetal exposure to anti-androgenic chemicals. However, the cause of TDS in humans remains to be determined. [source] Categorical Perception and Conceptual Judgments by Nonhuman Primates: The Paleological Monkey and the Analogical ApeCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 3 2000Roger K. R. Thompson Studies of the conceptual abilities of nonhuman primates demonstrate the substantial range of these abilities as well as their limitations. Such abilities range from categorization on the basis of shared physical attributes, associative relations and functions to abstract concepts as reflected in analogical reasoning about relations between relations. The pattern of results from these studies point to a fundamental distinction between monkeys and apes in both their implicit and explicit conceptual capacities. Monkeys, but not apes, might be best regarded as "paleo-logicans" in the sense that they form common class concepts of identity on the basis of identical predicates (i.e., shared features). The discrimination of presumably more abstract relations commonly involves relatively simple procedural strategies mediated by associative processes likely shared by all mammals. There is no evidence that monkeys can perceive, let alone judge, relations-between-relations. This analogical conceptual capacity is found only in chimpanzees and humans. Interestingly, the "analogical ape," like the child, can make its analogical knowledge explicit only if it is first provided with a symbol system by which propositional representations can be encoded and manipulated. [source] | |||||||||||||||||||