bluuebunny/crossref_metadata_2025 huggingface dataset:
Convergent Validity and Test–Retest Reliability of the Oxford Physical Activity Questionnaire for Secondary School Students
Authors: Lubans David R. , Sylva Kathy , Osborn Zane
Published: May 2008

The purpose of this study was to examine the convergent validity and test–retest reliability of the Oxford Physical Activity Questionnaire (OPAQ), a self-administered questionnaire designed to assess the activity patterns of adolescents. The test–retest reliability of the OPAQ was assessed by administering the questionnaire on two occasions separated by 1 week (N = 87, mean age = 13.1 ± .9). Intraclass correlation (ICC) was used to examine the test–retest reliability of the OPAQ. The convergent validity of the OPAQ was evaluated using Caltrac accelerometers worn consecutively for 4 days (N = 51, mean age = 12.6 ± .5). Spearman's rank-order correlation was used to examine the convergent validity of the questionnaire. ICCs ranged from .76 to .91 and reliability was higher for males (r = .89) than females (r = .78). Correlations between self-reported physical activity and Caltrac accelerometer counts were related to vigorous physical activity (r = .33, p = .01) and moderate to vigorous activity (r = .32, p = .02). The OPAQ has excellent test–retest reliability and acceptable validity in comparison to other measures of youth physical activity.
Cognitive–Behavioural Therapy Combined With an Interpersonal Skills Component in the Treatment of Generalised Anxiety Disorder in Adolescent Females: A Case Series
Authors: Waters Allison M. , Donaldson Jillian , Zimmer-Gembeck Melanie J.
Published: May 2008

The present study describes the outcomes of a manualised treatment for generalised anxiety disorder (GAD) in female adolescents that combined traditional cognitive–behavioural therapy (CBT) with an interpersonal skills (IP) component. The CBT component included psychoeducation, somatic management, cognitive restructuring, exposure therapy and problem-solving. The IP component targeted interpersonal avoidance, passive and aggressive interpersonal styles, and co-rumination. Four female adolescents with a principal diagnosis of GAD participated in 10 weekly 1-hour sessions. Adolescent- and parent-report diagnostic interviews and questionnaires were completed at pre-, mid-, and posttreatment, and at 3-months follow-up. Reductions in GAD and depressive symptoms and improvements in interpersonal functioning for all participants on both adolescent- and parent-report measures suggest that the combination of CBT and IP can benefit adolescent girls with GAD.
Obsessive–Compulsive Contamination Fears and Anorexia Nervosa: The Application of the New Psycho-Educational Treatment of Danger Ideation Reduction Therapy (DIRT)
Authors: Drummond Lynne M. , Kolb Peter
Published: May 2008

The case history of a woman with severe and enduring anorexia nervosa and obsessive–compulsive disorder (OCD) with contamination fears is presented. These contamination fears centred on her fear of contamination by fat and fatty substances as she worried about gaining weight. Previous treatment with graded exposure had shown no clinically significant benefits. She was admitted to a specialist unit for the treatment of OCD as an inpatient. Due to the previous failure of the recognised psychological treatments for OCD it was decided to use the new psychoeducational approach of danger ideation reduction therapy (DIRT). This treatment resulted in an improvement in her OCD symptoms despite the fact that the emphasis of the treatment was on the risk of bacteria and dirt. It is believed that this is the first documented case of DIRT being used for a patient with anorexia nervosa and OCD.
Effects of pre-mating nutrition on mRNA levels of developmentally relevant genes in sheep oocytes and granulosa cells
Authors: Pisani Laura F , Antonini Stefania , Pocar Paola , Ferrari Stefania , Brevini Tiziana A L , Rhind Stewart M , Gandolfi Fulvio
Published: May 2008

The present study was designed to investigate the relationship between pre-mating nutrition and the relative amounts of a panel of developmentally relevant genes in ovine oocytes and granulosa cells. Cast age ewes were fed a ration providing 0.5× (0.5 M) or 1.5× (1.5 M) live weight maintenance requirements for 2 weeks before slaughter. The ewes were synchronized and superovulated with FSH and pregnant mares serum gonadotropin. At slaughter, oocytes and granulosa cells were aspirated from follicles >2 mm in diameter and the relative abundance of 8 and 17 transcripts in oocytes and granulosa cells respectively were analyzed by semi-quantitative RT-PCR. In the oocytes, no differences between groups were observed for five transcripts (GDF9, BMP15, c-kit, glucose transporter 1 (SLC2A1), and hexokinase 1), but a lower amount of glucose transporter 3 (SLC2A3), sodium/glucose cotransporter 1 (SLC5A1), and Na+/K+ ATPase mRNAs was detected in the 0.5 M group. Increased expression of PTGS2, HAS2, and the leptin receptor long form was observed in granulosa cells from the 0.5 M group. No differences between groups were observed for the other transcripts (early growth response factor-1, estrogen receptor-α, LH and FSH receptors, gremlin 1, pentraxin 3, KIT ligand, glucose transporters 1, 3, and 8, IGF1, IGF1 receptor, leptin receptor, and tumor necrosis factor-stimulated gene 6). Expression of leptin and sodium/glucose cotransporter 1 was not detected in both groups. The present data indicate that pre-mating nutrition is associated with alteration in the mRNA content in oocytes and surrounding follicle cells in ewes, which may account for the reduced reproductive performance typical of ewes that are fed a restricted ration for a short period of time before mating.
Epigenetic regulation in male germ cells
Authors: Zamudio Natasha M , Chong Suyinn , O'Bryan Moira K
Published: May 2008

In recent years, it has become increasingly clear that epigenetic regulation of gene expression is critical during spermatogenesis. In this review, the epigenetic regulation and the consequences of its aberrant regulation during mitosis, meiosis and spermiogenesis are described. The current knowledge on epigenetic modifications that occur during male meiosis is discussed, with special attention on events that define meiotic sex chromosome inactivation. Finally, the recent studies focused on transgenerational and paternal effects in mice and humans are discussed. In many cases, these epigenetic effects resulted in impaired fertility and potentially long-ranging affects underlining the importance of research in this area.
Thyroid hormones and seasonal reproductive neuroendocrine interactions
Authors: Nakao Nobuhiro , Ono Hiroko , Yoshimura Takashi
Published: May 2008

Many animals that breed seasonally measure the day length (photoperiod) and use these measurements as predictive information to prepare themselves for annual breeding. For several decades, thyroid hormones have been known to be involved in this biological process; however, their precise roles remain unknown. Recent molecular analyses have revealed that local thyroid hormone activation in the hypothalamus plays a critical role in the regulation of the neuroendocrine axis involved in seasonal reproduction in both birds and mammals. Furthermore, functional genomics analyses have revealed a novel function of the hormone thyrotropin. This hormone plays a key role in signaling day-length changes to the brain and thus triggers seasonal breeding. This review aims to summarize the currently available knowledge on the interactions between elements of the thyroid hormone axis and the neuroendocrine system involved in seasonal reproduction.
Kisspeptin and KISS1R: a critical pathway in the reproductive system
Authors: Gianetti Elena , Seminara Stephanie
Published: May 2008

In 2003, three groups around the world simultaneously discovered that KISS1R (GPR54) is a key gatekeeper of sexual maturation in both mice and men. Developmental changes in the expression of the ligand for KISS1R, kisspeptin, support its critical role in the pubertal transition. In addition, kisspeptin, a powerful stimulus of GNRH-induced gonadotropin secretion and may modulate both positive and negative sex steroid feedback effects at the hypothalamic level. Genetic studies in humans have revealed both loss-of-function and gain-of-function mutations in patients with idiopathic hypogonadotropic hypogonadism and precocious puberty respectively. This review examines the kisspeptin/KISS1R pathway in the reproductive system.
Animal models for fertility preservation in the male
Authors: Ehmcke Jens , Schlatt Stefan
Published: May 2008

Fertility preservation in the male is routinely focused on sperm. In clinical and veterinary settings, cryopreservation of sperm is a widely used tool. However, the goals for male fertility preservation differ between experimental models, maintenance of livestock, conservation of rare species, and fertility protection in men. Therefore very different approaches exist, which are adapted to the specialized needs for each discipline. Novel tools for male fertility preservation are explored targeting immature germ cells in embryonic or immature testes. Many options might be developed to combine germline preservation and generation of sperm ex vivo leading to interesting new perspectives. This review highlights current and future options for male fertility preservation with a special focus on animal models and a consideration of the various disciplines in need of novel tools.
Hormonal suppression for fertility preservation in males and females
Authors: Meistrich Marvin L , Shetty Gunapala
Published: May 2008

Methods to restore fertility of men and women sterilized by medical treatments and environmental toxicant exposures are under investigation. Rendering spermatogenesis and ovarian follicular development kinetically quiescent by suppression of gonadotropins has been proposed to protect them from damage by cytotoxic therapy. Although the method fails to protect the fertility of male mice and monkeys, gonadotropin and testosterone suppression in rats before or after cytotoxic therapy do enhance the recovery of spermatogenesis. However, the mechanism involves not the induction of quiescence but rather the reversal, by suppression of testosterone, of a block in differentiation of surviving spermatogonia caused by damage to the somatic environment. In men, only one of eight clinical trials was successful in protecting or restoring spermatogenesis after cytotoxic therapy. In women, protection of primordial follicles in several species from damage by cytotoxic agents using GnRH analogs has been claimed; however, only two studies in mice appear convincing. The protection cannot involve the induction of quiescence in the already dormant primordial follicle but may involve direct effects of GnRH analogs or indirect effects of gonadotropin suppression on the whole ovary. Although numerous studies in female patients undergoing chemotherapy indicate that GnRH analogs might be protective of ovarian function, none of the studies showing protection were prospective randomized clinical trials and thus they are inconclusive. Considering interspecies differences and similarities in the gonadal sensitivity to cytotoxic agents and hormones, mechanistic studies are needed to identify the specific beneficial effects of hormonal suppression in select animal models that may be applicable to humans.
Phosphatidylinositol 3-kinase signaling in mammalian preimplantation embryo development
Authors: O'Neill Chris
Published: May 2008

The development of the preimplantation mammalian embryo is an autopoietic process; once initiated development proceeds without an absolute requirement for external information or growth cues. This developmental autonomy is partly explained by the generation of autocrine trophic ligands that are released and act back on the embryo via specific receptors. Several embryotrophic ligands cause receptor-dependent activation of 1-o-phosphatidylinositol 3-kinase. This enzyme phosphorylates phosphatidylinositol-4,5-bisphosphate to form phosphatidylinositol-3,4,5-trisphosphate. Genetic or pharmacological ablation of this enzyme activity disrupts normal development of preimplantation embryos. Phosphatidylinositol-3,4,5-trisphosphate is a membrane lipid that acts as a docking site for a wide range of proteins possessing the pleckstrin homology (PH) domain. Such proteins are important regulators of cell survival, proliferation, and differentiation. RAC-α serine/threonine protein kinase is an important PH domain protein and its activity is required for normal preimplantation embryo development and survival. The activity of a range of PH domain proteins is also implicated in the normal development of the embryo. This review critically examines the evidence for the activation of 1-o-phosphatidylinositol 3-kinase in the generation of pleiotypic trophic response to embryotrophins in the autopoietic development of the preimplantation embryo.
Inhibin, activin, follistatin and FSH serum levels and testicular production are highly modulated during the first spermatogenic wave in mice
Authors: Barakat Badia , O'Connor Anne E , Gold Elspeth , de Kretser David M , Loveland Kate L
Published: May 2008

Testicular development is governed by the combined influence of hormones and proteins, including FSH, inhibins, activins and follistatin (FST). This study documents the expression of these proteins and their corresponding mRNAs, in testes and serum from mice aged 0 through 91 days post partum (dpp), using real-time PCR, in situ hybridisation, immunohistochemistry, ELISA and RIA. Serum immunoactive total inhibin and FSH levels were negatively correlated during development, with FSH levels rising and inhibin levels falling. Activin A production changed significantly during development, with subunit mRNA and protein levels declining rapidly after 4 dpp, while simultaneously levels of the activin antagonists, FST and inhibin/activin βC, increased. Inhibin/activin βA and βB subunit mRNAs were detected in Sertoli, germ and Leydig cells throughout testis development, with the βA subunit also detected in peritubular myoid cells. The α, βA, βB and βC subunit proteins were detected in Sertoli and Leydig cells of developing and adult mouse testes. While βA and βB subunit proteins were observed in spermatogonia and spermatocytes in immature testes, βC was localised to leptotene and zygotene spermatocytes in immature and adult testes. Nuclear βA subunit protein was observed in primary spermatocytes and nuclear βC subunit in gonocytes and round spermatids. The changing spatial and temporal distributions of inhibins and activins indicate that their modulated synthesis and action are important during onset of murine spermatogenesis. This study provides a foundation for evaluation of these proteins in mice with disturbed testicular development, enabling their role in normal and perturbed spermatogenesis to be more fully understood.
Laparoscopos csomózásr
Authors: Barabás Loránd , Sipos Péter
Published: May 2008

Absztrakt

A sebek fonallal való zárását a sebészet és a technika fejlődésének következtében rutinszerűen a 20. században kezdték alkalmazni. A nyitott műtéteknél alkalmazott fonalcsomózási technika könnyen elsajátítható és alkalmazható, ezzel szemben a laparoscopos műtétek során a csomózás nehezebb, és új problémákat vetett fel. A laparoscopos érlekötés, varrás, anastomosis készítése kiszélesítette a laparoscopos sebészet lehetőségeit. A laparoscopos csomó elkészítésének helye vagy intracorporalis, vagy extracorporalis. A leggyakrabban használt intracorporalis csomó lehet a “tumble square knot”, Dundee-, Aberdeen-, hajóscsomó és Blood-csomó. Az intracorporalis csomózás kivitelezése időnként nehéz, ami a kétdimenziós kép, a tactilis érzés hiányára és a korlátozott mozgási lehetőségre vezethető vissza, hátránya, hogy meglazulhat. A legismertebb extracorporalis csomók: Duncan-, Roeder-, módosított 4-S Roeder-, Tayside-, Yanni- és GEA-csomó. Az extracorporalis csomózás kivitelezése könnyebb, hátránya, hogy a csomózás ideje alatt a műtéti terület szemellenőrzése megszakad, a csomó helyére tolása közben a túlzott feszülés szöveti traumát okozhat. A különböző szövetekhez és fonaltípusokhoz különböző csomó és csomóletoló eszköz használata ajánlott. A robotsebészet bevezetésével a laparoscopos varrás és csomózás pontossága, biztonsága megnőtt, a műtéti idő lerövidülhet, ugyanakkor az alapműveletek gyakorlására is mód nyílik.
Jejunalis polyposisból származó heveny gastrointestinalis vérzés diagnosztikája és eredményes kezeléser
Authors: Sugár István , Forgács Bence , Bognár Gábor , Szabolcs Zoltán , Zalatnay Attila , Ondrejka Pál
Published: May 2008

Absztrakt

A szerzők egy 50 éves férfi esetét ismertetik, akinek masszív gastrointestinalis vérzése kiterjedt jejunalis polyposisból származott. Ismertetik a diagnosztikus nehézségeket, majd az eredményes műtéti kezelést. A raritásnak tartható eset kapcsán saját tapasztalataik és az irodalmi ismeretek alapján összefoglalják a vékonybél-eredetű, heveny gastrointestinalis vérzés diagnosztikájának és terápiájának lehetőségeit.
Kétoldali légmell egyidejű műtéti kezelése videothoracoscopos (VATS) műtéttelr
Authors: Balogh Gábor , Almuhtadi Khaled , ifj. Balogh Gábor , Patak Krisztina , Zádori Péter , Bogyó Levente , Tóth László
Published: May 2008

Absztrakt

A szerzők egy fiatal férfi beteg kétoldali légmellének videothoracoscopos műtéttel történő egyidejű kezeléséről számolnak be. A műtét eredményességében jelentős szerepet kapott az endoscopos varrógép. A szerzők megállapítják, hogy a kétoldali légmell videothoracoscopos kezelése (VATS) a beteg számára minimális megterhelést jelent, és a korábbi módszereknél eredményesebb. Különösen kétoldali pneumothorax esetében a kockázatot és a műtéti szövődmények kialakulását jelentősen csökkentő műtéti módszer.
Az ischaemiatolerancia növelésének lehetőségei a májsebészetbenr
Authors: Szijártó Attila
Published: May 2008

Absztrakt

A szerző az ischaemia-reperfusio kapcsán fellépő kórállapotokat elemzi kísérletes májműtétek kapcsán. Célkitűzés: Kísérleteim célja a máj kiterjesztett, műtéti resectiója során fellépő ischaemia és az ischaemiatolerancia, továbbá egy, endogén defenzív mechanizmussal bíró ischaemiás preconditionálás (IP), illetve az oxidatív stressz hatására aktiválódó poli(ADP-ribóz) polimeráz enzimet gátló vegyület (PJ-34) és az antioxidáns potenciállal bíró glutamin (Gln) kísérletes vizsgálata volt IR modellben. Anyagok és módszer: Az első kísérletben Wistar-patkányok máján változó időtartamú (30-45-60-90 perc) segmentalis ischaemiát hoztunk létre, IP-sal kiegészítve. A második kísérletsorozatban PJ-34-, Gln-előkezelés történt 60 perces ischaemiával. A microcirculatiós változásokat laser Doppler flowmeterrel mértük. A módszer alkalmazásához új technikai kritériumokat állítottunk fel, illetve a kapott értékeket, matematikai analízist követően, statisztikai feldolgozásra alkalmassá tettük. Vizsgáltuk a szövettani változásokat, az antioxidáns-szinteket, konvencionális laboratóriumi és TNF-α szinteket mértünk. Eredmények, megbeszélés: A máj a 30 perces ischaemiát jól tolerálja, a 45 és 60 perces kirekesztés jelentős áramlásbeli változásokat okoz. A 90 perces ischaemia nem tolerálható. Az IP szignifikáns reperfusiós áramlási javulást és szérum-TNF-α csökkenést okoz a 45 és 60 perces ischaemia előtt alkalmazva. PJ-34 PARP-inhibitor-, illetve Gln-előkezelés, 60 perc reperfusiót vizsgálva, javítja a microcirculatiót. Aktivált kaszpáz-3 immunhisztokémiával végzett vizsgálatok során a PJ-34 PARP-inhibitor- és Gln-előkezelések hatására szignifikánsan magasabb apoptosis volt detektálható a kontrollcsoporthoz képest. A májszöveti és szérumantioxidáns-paramétereket mind az IP, mind a Gln-előkezelés javították.
Effects of dynamic indentation on the mechanical response of materials
Authors: Cordill M.J. , Moody N.R. , Gerberich W.W.
Published: June 2008

Dynamic indentation techniques are often used to determine mechanical properties as a function of depth by continuously measuring the stiffness of a material. The dynamics are used by superimposing an oscillation on top of the monotonic loading. Of interest was how the oscillation affects the measured mechanical properties when compared to a quasi-static indent run at the same loading conditions as a dynamic. Single crystals of nickel and NaCl as well as a polycrystalline nickel sample and amorphous fused quartz and polycarbonate have all been studied. With respect to dynamic oscillations, the result is a decrease of the load at the same displacement and thus lower measured hardness values of the ductile crystalline materials. It has also been found that the first 100 nm of displacement are the most affected by the oscillating tip, an important length scale for testing thin films, nanopillars, and nanoparticles.
Co- and Fe-based multicomponent bulk metallic glasses designed by cluster line and minor alloying
Authors: Wang Q. , Zhu C.L. , Li Y.H. , Cheng X. , Chen W.R. , Wu J. , Qiang J.B. , Wang Y.M. , Dong C.
Published: June 2008

Bulk metallic glass (BMG) formations in Co- and Fe-based alloy systems are investigated by using our cluster line approach in combination with minor alloying principle. Basic ternary alloy compositions in Co–B–Si, Fe–B–Y, and Fe–B–Si systems are first determined by cluster lines defined by linking special binary clusters to third elements. Then the basic ternary alloys are further minor alloyed with 3 to 5 at.% Nb to improve glass-forming abilities (GFAs) and ϕ3 mm BMGs are formed in (Co8B3–Si)–Nb and (Fe8B3–Y)–Nb but not in (Fe8B3–Si)–Nb, TM8B3 (TM = Fe, Co) being the most compact binary cluster. The BMGs are expressed approximately with a unified simple composition formula: (TM8B3)1M1, M = (Si, Nb) or (Y, Nb). Finally, mutual Fe and Co substitutions further improve the GFAs as well as the soft magnetic properties, e.g., Is reaching 0.98 T and Hc < 6 A/m for the Co–Fe–B–Si–Nb BMGs. Using the (cluster)1(glue atom)1 model, a new ternary BMG Fe8B3Nb1 is obtained.
Técnica, corpo e coisificação: notas de trabalho sobre o tema da técnica em Theodor W. Adorno
Authors: Bassani Jaison José , Vaz Alexandre Fernandez
Published: June 2008

Trata-se aqui de umas notas de trabalho sobre o tema da técnica em Theodor W. Adorno. O ensaio Educação após Auschwitz e um conjunto de aforismos que compõem o livro Minima moralia são tomados como fontes principais, mas também como roteiro de investigação. As críticas de Adorno à técnica aparecem em vários registros e privilegiamos, nos marcos de nossa reflexão, as relacionados ao corpo e à produção da consciência, elementos que se combinam diversamente nas obras pesquisadas, mas que encontram seu desiderato na crítica ao mundo administrado e aos destinos da subjetividade. Nossos resultados mostram que nas reflexões de Adorno o profundo processo de embrutecimento do humano e a supressão de quaisquer traços de particularidade aparecem intimamente relacionados com o crescente processo de tecnificação, o que por sua vez engendra uma certa pedagogia dos gestos e do corpo. Sugere-se, neste sentido, que a técnica mais refinada não necessariamente leva a um aumento das possibilidades humanas, mas, talvez encaminhe, tendencialmente, a uma escravização do corpo por meio da incorporação dos processos reificadores da tecnificação.
The emerging role of the Ikaros stem cell factor in the neuroendocrine system
Authors: Ezzat Shereen , Asa Sylvia L
Published: May 2008

In this review, we cover the evidence implicating Ikaros as a key factor whose transcriptional actions and chromatin remodeling properties determine the fate of hypothalamic neuroendocrine and pituitary cell population expansion. We propose that the governing mechanisms involved in the regulation and action of Ikaros are of importance during developmental as well as neoplastic transitions.
Leptin modulates the expression of its receptors in the hypothalamic–pituitary–ovarian axis in a differential way
Authors: Di Yorio M P , Bilbao M G , Pustovrh M C , Prestifilippo J P , Faletti A G
Published: May 2008

To investigate the expression of leptin receptors (Ob-R) in the rat hypothalamus–pituitary–ovarian axis, immature rats were treated with eCG/hCG and Ob-R expression was evaluated by western blot analysis. The Ob-R expression increased 24 h after eCG administration in all the tissues assayed. In the hypothalamus, these levels immediately decreased to those obtained without treatment. In the pituitary, the Ob-R expression continued to be elevated 48 h after eCG administration, whereas the hCG injection did not modify these levels. Similar results were obtained with the ovarian long isoform. To assess the effect of leptin on its receptors, Ob-R was assessed in hypothalamus, pituitary and ovarian explants cultured in the presence or absence of leptin (0.3–500 ng/ml). In the hypothalamus, we found a biphasic effect: the Ob-R expression was either reduced or increased at low or high concentrations of leptin respectively. LH-releasing hormone secretion increased at 1 ng/ml. In the pituitary, Ob-R increased at 10 or 30 ng/ml of leptin for the long and short isoforms respectively. Leptin also induced an increase in LH release at 30 ng/ml. In the ovarian culture, the presence of leptin produced an increase in Ob-R expression at different ranges of concentrations and a dose-dependent biphasic effect on the progesterone production. In conclusion, all these results clearly suggest that leptin is able to modulate the expression of its own receptors in the reproductive axis in a differential way. Moreover, the positive or negative effect that leptin exerts on the ovulatory process may be dependent on this regulation.
MafA is a dedicated activator of the insulin gene in vivo
Authors: Artner Isabella , Hang Yan , Guo Min , Gu Guoqiang , Stein Roland
Published: May 2008

As successful generation of insulin-producing cells could be used for diabetes treatment, a concerted effort is being made to understand the molecular programs underlying islet β-cell formation and function. The closely related MafA and MafB transcription factors are both key mammalian β-cell regulators. MafA and MafB are co-expressed in insulin+β-cells during embryogenesis, while in the adult pancreas only MafA is produced in β-cells and MafB in glucagon+α-cells. MafB−/− animals are also deficient in insulin+ and glucagon+ cell production during embryogenesis. However, only MafA over-expression selectively induced endogenous Insulin mRNA production in cell line-based assays, while MafB specifically promoted Glucagon expression. Here, we analyzed whether these factors were sufficient to induce insulin+ and/or glucagon+ cell formation within embryonic endoderm using the chick in ovo electroporation assay. Ectopic expression of MafA, but not MafB, promoted Insulin production; however, neither MafA nor MafB were capable of inducing Glucagon. Co-electroporation of MafA with the Ngn3 transcription factor resulted in the development of more organized cell clusters containing both insulin- and glucagon-producing cells. Analysis of chimeric proteins of MafA and MafB demonstrated that chick Insulin activation depended on sequences within the MafA C-terminal DNA-binding domain. MafA was also bound to Insulin and Glucagon transcriptional control sequences in mouse embryonic pancreas and β-cell lines. Collectively, these results demonstrate a unique ability for MafA to independently activate Insulin transcription.
The effect of activated carbon on partitioning, desorption, and biouptake of native polychlorinated biphenyls in four freshwater sediments
Authors: Sun Xueli , Ghosh Upal
Published: June 2008

The present study evaluated the effect of activated carbon amendment in four freshwater sediments from the Great Lakes (North America) areas of concern with a wide range of sediment geochemical characteristics (0.83–5.1% total organic carbon) and polychlorinated biphenyl (PCB) concentrations (0.33–84.7 μg/g). The work focused on understanding the impact of activated carbon amendment on PCB aqueous partitioning, PCB desorption characteristics, and PCB biouptake in a freshwater oligochaete (Lumbriculus variegatus). The results showed that PCB aqueous equilibrium concentrations, rapid desorption fractions, and biouptake by the oligochaete were reduced after activated carbon amendment. Addition of activated carbon at a dose of 0.5-fold native organic carbon reduced PCB bioaccumulation by 42% for Niagara River sediment, 85% for Grasse River sediment, 74% for Milwaukee River sediment 1, and 70% for Milwaukee River sediment 2. A linear relationship was observed between log biota–sediment accumulation factor and the first 6-h desorption fractions for each PCB homologue for treated and untreated sediments. Waterlipid bioconcentration factors for PCB congeners were largely conserved after amendment with activated carbon. Our present results suggest that at steady state, changes in the aqueous PCB concentrations can be used to predict changes in PCB bioaccumulation in deposit-feeding organisms. Thus, use of advanced pore-water measurement techniques, such as solid-phase extraction passive samplers, may be suitable for long-term monitoring of treatment performance.
Frequency of detectable serum IgG concentrations in precolostral calves
Authors: Chigerwe Munashe , Tyler Jeff W. , Nagy Dusty W. , Middleton John R.
Published: June 2008

Objective—To determine the prevalence of detectable serum IgG concentrations in calves prior to ingestion of colostrum and to assess whether a detectable IgG concentration was related to dam parity, calf birth weight, calf sex, season of calving, or infectious agents that can be transmitted transplacentally.

Animals—170 Holstein dairy calves.

Procedures—Serum samples were obtained from calves prior to ingestion of colostrum, and serologic testing for bovine viral diarrhea virus (BVDV) and Neospora caninum was performed. Relative risk, attributable risk, population attributable risk, and population attributable fraction for calves with a detectable serum IgG concentration attributable to positive results for N caninum and BVDV serologic testing were calculated. Logistic regression analysis was used to determine whether dam parity, calf sex, season of calving, and calf weight were associated with precolostral IgG concentration.

Results—90 (52.9%) calves had a detectable total serum IgG concentration (IgG ≥ 16 mg/dL). Relative risk, attributable risk, population attributable risk, and population attributable fraction for calves with a detectable serum IgG concentration attributable to positive results for N caninum serologic testing were 1.66, 0.34, 0.014, and 0.03, respectively. Calf sex, calf birth weight, and season of calving were not significant predictors for detection of serum IgG in precolostral samples.

Conclusions and Clinical Relevance—Prevalence of IgG concentrations in precolostral serum samples was higher than reported elsewhere. There was no apparent link between serum antibodies against common infectious agents that can be transmitted transplacentally and detection of measurable serum IgG concentrations.
Dielectric measurements of new antiferroelectric liquid crystals
Authors: Perkowski P. , Ogrodnik K. , Łada D. , Piecek W. , Rutkowska J. , Raszewski Z. , Żurowska M. , Dąbrowski R. , Sun X.
Published: May 2008

Three new pure antiferroelectric materials, synthesized at the Military University of Technology (MUT), were investigated by dielectric means. Clear relaxation modes were detected, i.e., Soft, Goldstone, low frequency in-phase (PL) as well high frequency anti-phase (PH) modes for paraelectric Sm A*phase, ferroelectric Sm C* phase and antiferroelectric Sm CA* phase, respectively. Additionally, a high relaxation mode in Sm CA* was found. The relaxation frequencies fR of the observed modes were calculated from Cole-Cole diagrams.
Effect of various surfactants and their concentration on controlled release of captopril from polymeric matrices
Authors: Nokhodchi Ali , Hassan-Zadeh Davoud , Monajjem-Zadeh Farnaz , Taghi-Zadeh Nita
Published: May 2008

Effect of various surfactants and their concentration on controlled release of captopril from polymeric matrices

Various methods are available to formulate water soluble drugs into sustained release dosage forms by retarding the dissolution rate. One of the methods used to control drug release and thereby prolong therapeutic activity is to use hydrophilic and lipophilic polymers. In this study, the effects of various polymers such as hydroxypropyl methylcellulose (HPMC), ethylcellulose (EC) and sodium carboxymethylcellulose (CMC) and surfactants (sodium lauryl sulphate, cetyltrimethylammonium bromide and Arlacel 60) on the release rate of captopril were investigated. The results showed that an increase in the amount of HPMC K15M resulted in reduction of the release rate of captopril from these matrices. When HPMC was partly replaced by NaCMC (the ratio of HPMC/NaCMC was 5:1), the release rate of the drug significantly decreased. However, there was no significant difference in release rate of captopril from matrices produced with ratios of 5:1 and 2:1 of HPMC/NaCMC. The presence of lactose in matrices containing HPMC and NaCMC increased the release rate of captopril. It was interesting to note that although partial replacement of HPMC by EC reduced the release rate of the drug (ratio of HPMC/EC 2:1), the release rate was increased when the ratio of HPMC/EC was reduced to 1:1. The effects of various surfactants on the release rate of captopril from HPMC/EC (1:1) matrices were also investigated. The results showed that the surfactants did not significantly change the release rate of the drug. Release data were examined kinetically and the ideal kinetic models were estimated for the drug release. The kinetic analysis of drug release data from various formulations showed that incorporation of surfactants in HPMC/EC matrices did not produce a zero-order release pattern.
Anti-inflammatory and analgesic activities of some newly synthesized pyridinedicarbonitrile and benzopyranopyridine derivatives
Authors: Hosni Hanaa , Abdulla Mohamed
Published: May 2008

Anti-inflammatory and analgesic activities of some newly synthesized pyridinedicarbonitrile and benzopyranopyridine derivatives

In continuation of our search for new substituted pyridine based anti-inflammatories, reaction of 1-(2-thienyl or furanyl)-3-(2-hydroxyphenyl)-2-propen-1-ones (1) with malononitrile in alcoholic KOH solution afforded a mixture of 4-alkoxy-2-(2-thienyl or furanyl)-5H-[1]benzopyrano[3,4-c]pyridine-5-ones (2) and 2-alkoxy-4-amino-6- (2-thienyl or furanyl)-3,5-pyridinedicarbonitriles (3). Some of the synthesized compounds were evaluated for their anti-inflammatory and analgesic activities compared to diclofenac potassium as positive control. Detailed synthesis, spectroscopic and toxicity data are reported.
Comparison between two cyclooxygenase inhibitors in an experimental dry eye model in albino rabbits
Authors: EL-Shazly Amany , EL-Gohary Amal , EL-Shazly Laila , EL-Hossary Ghada
Published: May 2008

Comparison between two cyclooxygenase inhibitors in an experimental dry eye model in albino rabbits

The purpose of this study was to compare the topical anti-inflammatory effects of the nonselective cyclooxygenase (COX) inhibitor, ketorolac, with the selective COX-2 inhibitor, nimesulide, in an animal model of dry eye in albino rabbits. All animals were examined by the Schirmer test, tear break-up time (TBUT) and fluorescein corneal staining test. Dry eye model showed significant reduction in tear volume, TBUT, corneal staining and histopathological signs of dryness and inflammation. On treating dry eye model with nimesulide 0.1% eye drops and ketorolac 0.5% eye drops, there were improvements in Schirmer test values, TBUT and fluorescein corneal staining and histopathologically reduced inflammatory reaction, with signs of healing and regeneration. Both nimesulide and ketorolac ameliorate atropine sulphate induced dry eye in albino rabbits. The use of selective COX-2 inhibitor, nimesulide, is preferred to avoid local and systemic side effects which may occur with the use of the nonselective COX inhibitor, ketorolac.
The Potential of Cardiac Markers to Improve Patient Management
Authors: Müller Christian
Published: May 2008

The Potential of Cardiac Markers to Improve Patient Management

B-type natriuretic peptide (BNP) is a quantitative marker for heart failure. The use of BNP in patients with dyspnea has consistently shown to improve patient management and reduce treatment cost. Additional indications with the potential to improve patient management include treatment monitoring in acute and chronic heart failure, pulmonary embolism, and coronary artery disease.
Improved Cardiac Patient Management Through Cardiac Markers
Authors: Herzig Birgit
Published: May 2008

Improved Cardiac Patient Management Through Cardiac Markers

Cardiac markers enable the diagnosis and characterization of cardiac diseases. While the highly sensitive troponin assay is specific for myocardial infarction, myeloperoxidase is a powerful tool for early determination of plaque formation. Homocysteine is independently associated with numerous neurodegenerative diseases, cardiovascular events and stroke in particular. Elevated plasma concentrations predict outcome and help identify high-risk groups most likely to benefit from prevention and therapy. Homocysteine turned out as a valuable marker for early diagnoses of folate and B-vitamin deficiencies that are involved in anemias and numerous chronic diseases. This article presents the innovative marker MPO, the well established marker troponin and the versatile and useful marker homocysteine, and explains their importance in cardiac patient management.
Bone Markers - Their Nature and Clinical Use
Authors: Theis Manfred
Published: May 2008

Bone Markers - Their Nature and Clinical Use

Bone remodeling units are the centerpiece of bone metabolism. They are fueled by a synchronized and well balanced interaction of osteoclasts and osteoblasts, the activity of which releases specific substances known as bone markers into the blood. Resorption markers result from osteoclastic activity, formation markers from osteoblastic activity, and turnover markers from both cell types. In clinical practice, bone markers are today widely used for monitoring of antiresorptive therapy and patient compliance. There is strong evidence that they are also useful for risk assessment with respect to osteoporosis, here complementing established imaging methods. Other possible and partly not yet investigated indications include monitoring of side-effects of certain therapeutic drugs and oncology. In particular the combination of resorption and formation markers may open up a more differentiated insight into the metabolic situation of a patient's bone. The activity of osteoclasts and osteoblasts is triggered and modulated by numerous factors, some of which are of endocrine nature. Easily measurable in today's laboratory are for instance PTH, calcitonin and vitamin D. While calcitonin is not widely used in osteology, PTH and vitamin D define risk factors for an accelerated loss of bone and impaired mineralization of osteoid with the related diseases of osteoporosis, ricketts and osteomalacia. Recent developments in lab diagnosis of bone diseases focus on rheumatic diseases like rheumatoid arthritis, where anti-CCP is a much more specific marker than the common rheuma factors.
Advances in the Genetic Basis of Ischemic Stroke
Authors: Stanković Sanja , Majkić-Singh Nada
Published: May 2008

Advances in the Genetic Basis of Ischemic Stroke

As one of the leading causes of death within both the developed and developing world, stroke is a world-wide problem. About 80% of strokes are ischemic. It is caused by multiple genetic factors, environmental factors, and interactions among these factors. There is a long list of candidate genes that have been studied for a possible association with ischemic stroke. Among the most widely investigated genes are those involved in haemostasis, inflammation, nitric oxide production, homocysteine and lipid metabolism, renin-angiotensin-aldosterone system. Combined link-age/association studies have demonstrated that genes encoding PDE4D and ALOX5AP confer risk for stroke. We review the studies of these genes which may have potential application on the early diagnosis, prevention and treatment ischemic stroke patients.
Certainty in an Uncertain World - A Clinicians' Viewpoint of Sensitivity and Precision
Authors: Twomey Patrick
Published: May 2008

Certainty in an Uncertain World - A Clinicians' Viewpoint of Sensitivity and Precision

Clinical practice is evolving as research evolves from the bench to the bedside. Similarly, analytical technologies are improving on an annual basis. Rightly or wrongly, increased emphasis is now placed by clinicians on such investigations to the detriment of clinical history and examination. As people live longer, the prevalence of long-term conditions such as thyroid disease, cardiovascular disease and malignancies is increasing. Clinical biochemistry assays play an important part in the management (screening, diagnosis, prognosis and monitoring) of such conditions. This is reflected in the UK since 2004 by the primary care contract where over 100 of the 550 clinical points depend on clinical biochemistry assay results. Inter-assay results may differ due to bias, precision, assay specificity and assay sensitivity. To date, little emphasis has been placed on the potential clinical effect of precision. This presentation will explore the effect that assay precision can have on the management of important long-term conditions such as thyroid disease, cardiovascular disease and malignancies.
Dilemmas and Controversies in the Interpretation of Laboratory Results
Authors: Popović Danica , Popović Mirko
Published: May 2008

Dilemmas and Controversies in the Interpretation of Laboratory Results

Concentration of many substances in blood is a good indicator of the physiologic state of a patient. It is usual that results obtained represent the real concentration of tested substances in a patient, that is, represent his physiological state. The influence of some factors indicates that this assumption is not always true. Mistakes owing to analytic factors are reduced to the least possible rate by using the quality control. Also, many nonanalytic factors can change the concentration of one or more substances in the sample, so the results obtained are not an indicator of the physiological state of the patient. Results of clinical-biochemical determination are interpreted by comparing with the reference values and so the conclusion is made by a comparison method. In order to perform this process properly, reference values for each specific parameter are necessary. Cyclic variations, physical activity, stress, and other factors significantly affect the obtained result analysis. In the interpretation of results, these specificities have to be considered, otherwise they will be interpreted as pathologic, which leads to wrong conclusions. Inadequate preparation of a patient for a certain analysis and disrespect for rules regarding preparation and sample analyzing can lead to drastic deviation of results from the real values. For those reasons there are certain dilemmas and controversies in the result interpretation.
Status of Development and Implementation of Medical Laboratories Accreditation in Serbia
Authors: Gligić Ljubinka
Published: May 2008

Status of Development and Implementation of Medical Laboratories Accreditation in Serbia

Through the release of the SRPS ISO 15189:2008 standard entitled >>Medicinske laboratorije: posebni zahtevi za kvalitet i kompetentnost<< conditions have been created for medical laboratory accreditation in Serbia. The application of the ISO 15189:2007 standard is an accepted mechanism for improvement of the quality of medical laboratory services throughout EU today. In that way, different approaches to the quality improvement of medical laboratories have been harmonized. Functional organisation of the accreditation process of medical laboratories in most European countries is mainly carried out in cooperation with national accreditation bodies, medical experts appointed by scientist associations and health departments. This type of collaboration has proven successful in the United Kingdom, Germany, Hungary, France, Finland, Croatia, etc. The experiences of the Accreditation Board of Serbia (ABS) in medical laboratory accreditation according to the SRPS ISO/IEC 17025:2006 standard (5 laboratories have been accredited) and the positive experiences of European countries in accreditation process constitute the basis for the development of the program for medical laboratory accreditation in Serbia. The first step in this direction is the set-up of the Committee consisting of experts from different medical fields, ABS experts and representatives of the competent Ministry, as well as the definition of their tasks, such as: preparation of the necessary documentation, set-up and preparation of qualification criteria and training programs for assessors, participation in the development of the external quality assessment scheme through interlaboratory testing, liaison with the European organisations for accreditation, organisation of mutual assessments with national and international assessors, participation in decision making on accreditation and accreditation maintenance.
Biochemical Markers of Atherosclerosis
Authors: Đerić Mirjana , Kojić-Damjanov Sunčica , Čabarkapa Velibor , Eremić Nevena
Published: May 2008

Biochemical Markers of Atherosclerosis

This paper is a brief review of some lipid parameters and serum markers of inflammation in a view of their predictive relevance for the atherosclerotic disease. A discourse on the importance of measuring different lipids and lipoproteins, concentration of LDL particles and apolipoprotein levels is still underway. Also, the recommendations for apolipoprotein (a), phenotypization and other lipid markers have not yet been established. In recent years the recommendations imply simultaneous measuring of multiple markers and calculating the lipid index values such as lipid tetrad index (LTI), lipid pentad index (LPI) and atherogenic index of plasma (AIP). Several circulating markers of inflammation such as C-reactive protein, serum fibrinogen and elevated leukocyte number, are consistently associated with atherosclerosis. In spite of a lack of evidence on measuring the C-reactive protein in a wide population, the guidelines for its application in diagnostics and therapy of coronary heart disease were developed. Some proinflammatory cytokines, adhesion molecules and markers of leukocyte activation are promising markers, requiring, however, more detailed prospective evaluation. The question to be elucidated is if these inflammatory markers are directly involved in the pathogenic process.