bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of iron dysregulation in the pathogenesis of multiple sclerosis: an Egyptian study
Authors: Abo-Krysha N , Rashed L 
Published: April 2008

Background Iron is essential for virtually all types of cells and organisms. The significance of iron for brain function is reflected by the presence of receptors for transferrin on brain capillary endothelial cells. Iron imbalance is associated with proinflammatory cytokines and oxidative stress, which have been implicated in the pathogenesis of multiple sclerosis (MS). Transferrin receptor (TfR) is the major mediator of iron uptake. Its expression is increased to facilitate iron entrance into the cell. The increased serum level of soluble transferrin receptor (sTfR) may indicate an abnormal intracellular distribution of iron and a decrease in the cytoplasmic compartment. Objective Our objective is to assess the possible role of iron metabolism dysfunction in the pathogenesis of MS. Methods Thirty subjects were selected from the Neurology Department of Kasr El-Aini hospital, Cairo University: 20 MS patients, where nine patients were relapsing and progressive (secondary progressive (SP) of which six were secondary progressive active (SP-A) and three were secondary progressive stable (SP-S)), seven were relapsing–remitting active (RR-A) and four were primary progressive (PP); and 10 control subjects matched in age and sex. Each patient was subjected to a thorough general medical and neurological examination, Kurtzke MS rating scales, laboratory assessment, neuro-imaging, evoked potentials and quantitative determination of the indices of iron metabolism, such as serum iron and sTfR. Results The serum level of sTfR was significantly higher in our MS patients compared with the control group ( p = 0.0001). The levels were significantly higher in SP-A ( p = 0.001), SP-S ( p = 0.01), RR-A ( p = 0.0001) and PP ( p = 0.003) patients than in controls. Iron values were within normal limits in all patients. The increased serum sTfR level in non-anemic MS patients with active disease reflects the increased iron turnover. The elevation of sTfR levels in stable patients may indicate active inflammation with ongoing oxidative damage that is not detectable by history or examination. Conclusions Iron overload and upregulation of iron-handling proteins, such as TfR, in the MS brain can contribute to pathogenesis of Multiple Sclerosis and iron imbalance is associated with a prooxidative stress and a proinflammatory environment, this suggest that iron could be a target for MS therapy to improve neuronal iron metabolism.
The PI3K pathway regulates endochondral bone growth through control of hypertrophic chondrocyte differentiation
Authors: Ulici Veronica , Hoenselaar Katie D , Gillespie J Ryan , Beier Frank 
Published: April 2008

Abstract

Background
The majority of our bones develop through the process of endochondral ossification that involves chondrocyte proliferation and hypertrophic differentiation in the cartilage growth plate. A large number of growth factors and hormones have been implicated in the regulation of growth plate biology, however, less is known about the intracellular signaling pathways involved. PI3K/Akt has been identified as a major regulator of cellular proliferation, differentiation and death in multiple cell types.

Results and Discussion
Employing an organ culture system of embryonic mouse tibiae and LY294002, a pharmacological inhibitor of PI3K, we show that inhibition of the pathway results in significant growth reduction, demonstrating that PI3K is required for normal endochondral bone growth in vitro. PI3K inhibition reduces the length of the proliferating and particularly of the hypertrophic zone. Studies with organ cultures and primary chondrocytes in micromass culture show delayed hypertrophic differentiation of chondrocytes and increased apoptosis in the presence of LY294002. Surprisingly, PI3K inhibition had no strong effect on IGF1-induced bone growth, but partially blocked the anabolic effects of C-type natriuretic peptide.

Conclusion
Our data demonstrate an essential role of PI3K signaling in chondrocyte differentiation and as a consequence of this, in the endochondral bone growth process.
The evolutionary trajectory of the mating-type (mat) genes in Neurosporarelates to reproductive behavior of taxa
Authors: Wik Lotta , Karlsson Magnus , Johannesson Hanna 
Published: April 2008

Abstract

Background
Comparative sequencing studies among a wide range of taxonomic groups, including fungi, have led to the discovery that reproductive genes evolve more rapidly than other genes. However, for fungal reproductive genes the question has remained whether the rapid evolution is a result of stochastic or deterministic processes. The mating-type (mat) genes constitute the master regulators of sexual reproduction in filamentous ascomycetes and here we present a study of the molecular evolution of the four mat-genes (mat a-1, mat A-1, mat A-2 and mat A-3) of 20 Neurospora taxa.

Results
We estimated nonsynonymous and synonymous substitution rates of genes to infer their evolutionary rate, and confirmed that the mat-genes evolve rapidly. Furthermore, the evolutionary trajectories are related to the reproductive modes of the taxa; likelihood methods revealed that positive selection acting on specific codons drives the diversity in heterothallic taxa, while among homothallic taxa the rapid evolution is due to a lack of selective constraint. The latter finding is supported by presence of stop codons and frame shift mutations disrupting the open reading frames of mat a-1, mat A-2 and mat A-3 in homothallic taxa. Lower selective constraints of mat-genes was found among homothallic than heterothallic taxa, and comparisons with non-reproductive genes argue that this disparity is not a nonspecific, genome-wide phenomenon.

Conclusion
Our data show that the mat-genes evolve rapidly in Neurospora. The rapid divergence is due to either adaptive evolution or lack of selective constraints, depending on the reproductive mode of the taxa. This is the first instance of positive selection acting on reproductive genes in the fungal kingdom, and illustrates how the evolutionary trajectory of reproductive genes can change after a switch in reproductive behaviour of an organism.
Appendix mucokele laparoscopes műtéti megoldásar
Authors: Temesi Rita , Bezsilla János , Botos Ákos , Sikorszki László , Berecz János , Pap Tímea , Ludvig Zsuzsanna , Bende Sándor 
Published: April 2008

Absztrakt
A mucokele mucinnal telt, tágult, egy- vagy többrekeszű üreg, amely ritka az appendixben. A betegség legtöbbször tünetmentes, gyakran mellékleletként kerül felismerésre. Malignus elváltozások kizárása céljából részletes kivizsgálást igényel. A sebészi kezelés a műtéti lelettől, illetve a szövettani feldolgozástól függően appendectomiától a jobb oldali hemicolectomiáig terjedhet. Cikkünkben áttekintjük a betegség klinikumát, diagnosztikus lehetőségeit, valamint saját tapasztalataink figyelembevételével a műtéti megoldásokat. Öt beteget mutatunk be, kiknél három esetben jobb alhasban tapintható fájdalmatlan rezisztencia, egy esetben bizonytalan jobb alhasi fájdalmak, egy esetben hasi fájdalmak, fokozódó hasmenés miatt indult kivizsgálás, melynek során hasi ultrahang és CT-vizsgálatok felvetették a mucokele lehetőségét, colonoscopos vizsgálat intraluminalis eltérést nem talált. Laparoscopos exploratiót követően két esetben laparoscoppal asszisztált coecumkúp-resectiót, két esetben laparoscopos appendectomiát és egy esetben laparoscopos coecumkúp-resectiót végeztünk. A szövettani feldolgozás appendix mucokelét igazolt malignitásra utaló jel nélkül. Mindegyik betegünk szövődménymentesen gyógyult, a posztoperatív 5. napon emittáltuk őket. A mai napig, 6–30 hónapos követés után, betegeink panaszmentesek. Az appendix mucokele műtéti megoldásaként ajánlható a laparoscopos technika.
A magyar májátültetési program eredményeit befolyásoló egyes tényezők, különös tekintettel a hepatitis C-vírusrar
Authors: Nemes Balázs 
Published: April 2008

Absztrakt
A szerző a magyarországi májátültetési program adatait elemzi (1995–2006 között), retrospektív vizsgálattal. A hepatitis C-vírus (HCV) talaján kialakult cirrhosis miatt végzett májátültetéseket külön elemzi. Összefüggést keres a korai C-vírus-rekurrencia és a szérumban mért HCV-RNS-titer, valamint a graftbiopsziákban észlelt szövettani elváltozások és a PCR-módszerrel vizsgált, endoplazmatikus reticulum stresszt moderáló hepatocellularis chaperonok expressiója között. Ismerteti, hogy a műtétek száma 10 év alatt megnégyszereződött. Az időszakokra bontott 1, 3 és 5 éves kumulatív betegtúlélés 55%, 45% és 39% (1995–1997), 72%, 64% és 61% (1998–2000), illetve 78%, 77% és 77% (2001–2004) volt. A teljes mortalitás 53%-ról 31%-ra, a 60 napon belüli halálozás 24%-ról 5%-ra csökkent. A HCV miatt transzplantált betegek 1, 3 és 5 éves kumulatív túlélése 64%, 55% és 51%, minden más krónikus indikáció esetén ez 73%, 66% és 63% volt. A HCV miatt transzplantáltaknál az 1 éven belül észlelt víruskiújulás aránya 43% volt összességében. A betegtúlélést befolyásoló tényezők Cox-regressziós multivariációs analízise alapján a műtét utáni veseelégtelenség, a hepaticus artéria thrombosisa, epeúti necrosis, cholangitis, valamint a pulmonalis és hasüregi fertőzés, intraoperatív kolloid infúzió (HES) és a vértranszfúzió mennyisége voltak. A HCV miatt májátültetett betegek posztoperatív biopsziáiban az XBP1, ATF6, HSP70, GRP98, GP96, Calnexin és Calreticulin chaperonok expressiója szignifikánsan magasabb volt az interferonkezelés előtt, mint egy év antivirális kezelés után, függetlenül a szérumban mért vírus-RNS-titertől. Acut rejectio esetén a chaperonexpressio szignifikánsan és nagyságrenddel kifejezettebb volt, mint a hepatitis C-vírus reaktivációjának szövettani jelei esetén. Megállapítja, hogy a HCV miatt végzett májátültetések után, a korai víruskiújulás összefüggésbe hozható a májátültetés után a szérumban mért emelkedett vírus-RNS-titerrel. Ez számszerűen is kifejezhető egy határérték formájában, amely felett a szövettani jelek és a klinikum is progresszív májkárosodást jelez. Ezeknél a betegeknél a statisztikai túlélés is rosszabb.
Do Conference Calls Affect Analysts' Forecasts?
Authors: Bowen Robert M. , Davis Angela K. , Matsumoto Dawn A. 
Published: April 2008

In 1998, the SEC expressed concern that conference calls encourage selective disclosure by revealing new information to financial analysts privy to the call. This study investigates whether the regular use of earnings-related conference calls increases the amount of information available to financial analysts by examining the effect of conference calls on analysts' forecast error and dispersion. Results indicate that conference calls increase analysts' ability to forecast earnings accurately, suggesting that these calls increase the total information available about a firm. We also find some evidence that conference calls decrease dispersion among analysts. Given conference calls were generally restricted during our sample period, our evidence suggests that conference calls may have contributed to an information gap between analysts privy to the call and the remainder of the investment community.
We also investigate whether conference calls differentially affect analysts' forecast errors depending on analysts' prior forecasting ability or brokerage-house affiliation. We find evidence suggesting that analysts with relatively weak prior forecasting performance benefit more from conference calls, suggesting that conference calls help “level the playing field” across analysts.
Product Costing and Pricing under Long-Term Capacity Commitment
Authors: Banker Rajiv D. , Hwang Iny , Mishra Birendra K. 
Published: April 2008

We develop a model to analyze optimal product-costing and pricing decisions in a dynamic information environment under long-term-capacity commitment. The arrival of new information about demand and cost parameters each period makes the problem complex. The optimal prices and capacity choices in our model cannot be decoupled as in Banker and Hughes' (1994) single-period model.
The optimal prices are based on product costs that are adjusted each period to reflect changes in expected variable costs as well as utilization of fixed activity resources. The charge for each fixed resource is monotonically increasing in the expected demand for that resource in each state given the optimal capacity choice. The average optimal prices across periods and states are similar to Banker and Hughes' (1994) benchmark prices.
Finally, we investigate a two-period version of the model to explore the optimality of carrying idle capacity. The optimal product-cost charge for fixed capacity is strictly less in the first period than in the second period when the firm expects demand growth.
Does Managerial Accounting Research Contribute to Related Disciplines? An Examination Using Citation Analysis
Authors: Mensah Yaw M. , Hwang Nen-Chen Richard , Wu Donghui 
Published: April 2008

This paper examines two issues. The first issue is the degree of relative isolation of managerial accounting research (MAR) from related disciplines. Using citations collected from the Web of Science, the study shows that MAR published during 1986–2000 in the four leading accounting journals is cited in journals in fields as diverse as economics, operations research, psychology, sociology, organizational behavior, and strategic management. Our findings support Kinney's (2001) observation that accounting researchers have a competitive advantage in areas relating to alternative business measurement structures.
The second issue the paper addresses is whether economics-based MAR papers make a greater contribution than papers based on other disciplines, as perceived from their respective citation rates. Our citation analysis finds no evidence that economicsbased papers are cited by non-accounting researchers at a higher rate than MAR based on other disciplines. Extending the comparison to accounting journals covered in the Web of Science did not change this conclusion. We interpret this as a refutation of the contention by Zimmerman (2001) that economics-based MAR papers are more likely to make significant contributions to knowledge.
We also report some preliminary evidence that the relevance of MAR to researchers publishing in non-accounting journals is waning. Although this finding is tentative, it may be an early warning signal that should be monitored in future research.
T-2 Toxin: Incidence and Toxicity in Poultry
Authors: Sokolović Marijana , Garaj-Vrhovac Verica , ŠImpraga Borka 
Published: April 2008

T-2 Toxin: Incidence and Toxicity in PoultryT-2 toxin is the most toxic type A trichothecene mycotoxin. It is the secondary metabolite of the Fusarium fungi, and is common in grain and animal feed. Toxic effects have been shown both in experimental animals and in livestock. It has been implicated in several outbreaks of human mycotoxicoses. Toxic effects in poultry include inhibition of protein, DNA, and RNA synthesis, cytotoxicity, immunomodulation, cell lesions in the digestive tract, organs and skin, neural disturbances and low performance in poultry production (decreased weight gain, egg production, and hatchability). Concentrations of T-2 toxin in feed are usually low, and its immunosuppressive effects and secondary infections often make diagnosis difficult. If at the onset of the disease, a change in diet leads to health and performance improvements in animals, this may point to mycotoxin poisoning. Regular control of grain and feed samples is a valuable preventive measure, and it is accurate only if representative samples are tested. This article reviews the incidence and toxic effects of T-2 toxin in poultry.
Severe Acute Copper Sulphate Poisoning: A Case Report
Authors: Sinkovič Andreja , Strdin Alenka , Svenšek Franci 
Published: April 2008

Severe Acute Copper Sulphate Poisoning: A Case ReportAs copper sulphate pentahydrate (CSP) is a common compound used in agriculture and industry, chronic occupational exposures to CSP are well known, but acute poisoning is rare in the Western world. This case report describes acute poisoning of a 33-year-old woman who attempted suicide by ingesting an unknown amount of CSP. On admission to the hospital, she had symptoms and signs of severe hemorrhagic gastroenteritis, dehydration, renal dysfunction and methaemoglobinaemia with normal serum copper level. Therapy included early gastric lavage, fluid replacement, vasoactive drugs, furosemide, antiemetic drugs, ranitidine, and antidotes methylene blue and 2,3-dimercaptopropane-1-sulphonate (DMPS). However, the patient developed severe intravascular haemolysis, acute severe hepatic and renal failure, as well as adrenal insufficiency. After prolonged, but successful hospital treatment, including haemodialysis and IV hydrocortisone, the patient was discharged with signs of mild renal and liver impairment. Our conclusion is that in severe cases of copper poisoning early supportive measures are essential. In addition, antidotes such as methylene blue for methaemoglobinaemia and chelating agent such as DMPS improve morbidity and survival of severely poisoned victims.
Workplace Mobbing
Authors: ŠOljan Ivana , Josipović-Jelić Željka , Kiš Anita 
Published: April 2008

Workplace MobbingWorkplace mobbing is a hostile and unethical communication, systematically aimed from one or more individuals towards mostly one individual, who are forced into a helpless position and are held in it by constant bullying. This article describes some of the most important characteristics of mobbing: offensive behaviour, organizational and non-organizational causes of this behaviour, the victim, and the consequences. Modern business environment is complex, dynamic, volatile, and requires better ability to adjust. Constant changes are a part of organizational reality, but they also produce an ideal environment for all kinds of conflicts. Conflicts are inevitable in every organization, but the task of its management is to identify them and resolve before they affect the workforce, productivity, and costs. The idea is to avert psychological abuse and aberrant behaviour such as mobbing that may cause physical and mental disorders. Mobbing is a problem of the modern society; as a violation of human rights it is relatively new and unrecognised in Croatia. Abuse is mostly psychological; it affects the victim's health and life, quality of work, productivity, profitability, and may lead to significant economic losses in the community. Mobbing can be averted by joint forces that would involve employees and management, medical and legal professionals, and even community as a whole. The more an organization pursues excellence based on trust and business ethics, the higher the probability that mobbing will be averted or stopped.
Screening for antidepressant, sedative and analgesic activities of novel fused thiophene derivatives
Authors: Wardakhan Wagnat , Abdel-Salam Omar , Elmegeed Gamal 
Published: April 2008

Screening for antidepressant, sedative and analgesic activities of novel fused thiophene derivativesThis study was aimed at the synthesis of fused benzothiophene derivatives containing heterocyclic moiety. The reaction of the tetrahydrobenzo[b]thiophene derivatives1a,bwith ethoxycarbonylisothiocyanate afforded the thiourea derivatives2a,b.Cyclization of the latter products gave the annulated benzo[b]thienopyrimidine derivatives3a,b.Compounds2a,band3aunderwent a series of heterocyclization reactions through the reaction with some chemical reagents to give the new benzo[b]thienopyrimidine derivatives5a,bto8a-c.Also, this work was extended to study the potential role of the novel synthesized thiourea derivative2aand benzo[b]thienopyrimidine derivatives3a, 5b, 6aand8bas antidepressant, sedative or analgesic agents at two doses (15 or 30 mg kg-1body mass). Some compounds (2a, 3aand5b) showed mild antidepressant activity in the forced-swimming test. No compound showed sedative effect. Visceral pain evoked byi.p.injection of acetic acid in mice was significantly inhibited by all compounds at a high doses.
A sensitive spectrophotometric method for the determination of H2-receptor antagonists by means of N-bromosuccinimide and p-aminophenol
Authors: Darwish Ibrahim , Hussein Samiha , Mahmoud Ashraf , Hassan Ahmed 
Published: April 2008

A sensitive spectrophotometric method for the determination of H2-receptor antagonists by means ofN-bromosuccinimide andp-aminophenolA simple, accurate and sensitive spectrophotometric method for determination of H2-receptor antagonists: cimetidine (CIM), famotidine (FAM), nizatidine (NIZ), and ranitidine hydrochloride (RAN) has been fully developed and validated. The method was based on the reaction of these drugs with NBS and subsequent measurement of the excessN-bromosuccinimide by its reaction withp-aminophenol to give a violet colored product (λmaxat 552 nm). Decrease in the absorption intensity (ΔA) of the colored product, due to the presence of the drug, was correlated with its concentration in the sample solution. Different variables affecting the reaction were carefully studied and optimized. Under optimal conditions, linear relationships with good correlation coefficients (0.9988--0.9998) were found between ΔAvalues and the corresponding concentrations of the drugs in a concentration range of 8--30, 6--22, 6--25, and 4--20 μg mL-1for CIM, FAM, NIZ, and RAN, respectively. Limits of detection were 1.22, 1.01, 1.08, and 0.74 μg mL-1for CIM, FAM, NIZ, and RAN, respectively. The method was validated in terms of accuracy, precision, ruggedness, and robustness; the results were satisfactory. The proposed method was successfully applied to the analysis of the above mentioned drugs in bulk substance and in pharmaceutical dosage forms; percent recoveries ranged from 98.5 ± 0.9 to 102.4 ± 0.8% without interference from the common excipients. The results obtained by the proposed method were comparable with those obtained by the official methods.
Laboratory optimization of process variables in reductive ozonolysis of methyl soyate
Authors: Throckmorton P. E. , Hansen L. I. , Christenson R. C. , Pryde E. H. 
Published: April 2008

AbstractThe laboratory experiments for reductive ozonolysis of methyl soyate were divided into four statistically designed groups, according to ozonolysis medium (methanol or water) and ozone carrier gas (oxygen or air). Each group comprised 27 separate experiments, each a one‐third replicate of a 34 factorial. Significant independent variables were determined by a preliminary set of experiments. Besides ozonolysis medium (X) and carrier gas (Y), the following significant independent variables were studied: medium/ester ratio (A), reduction catalyst (B), reduction pressure by hydrogen (C), and reduction temperature (D).By gas‐liquid partition chromatography of the dimethyl acetals of the two products, which included methyl azelaaldehydate (MAZDA) and pelargonic aldehyde (PDA), aldehyde yields were determined for each experiment in the statistical groups.Analysis of variance of the data (F‐test) showed the following main effects and interactions for yield of MAZDA where oxygen carrier gas, water as the ozonolysis medium, and palladium‐on‐carbon catalyst were used for reduction: Y, YA, YB, YD, AD, BD, and AC. Data fit (regression analysis) provided regression equations. Computer solution of these equations indicated optimum process levels. Based on these optimum levels, the predicted over‐all yield of MAZDA is 89% of theoretical.
Radiation‐induced changes on beef fat‐cephalin mixtures bygamma‐radiation. Inhibition ofcis‐trans isomerization
Authors: Kohn Rudolf 
Published: April 2008

AbstractIonizing radiation‐inducedcis‐trans isomerization of unsaturated bonds in beef fat was inhibited by the addition of phospholipid. Infrared absorption at 10.35µ (966 cm−1) ofγ‐irradiated beef fat‐dl‐a‐cephalin dipalmitate mixtures was less than that of beef fat alone. These decreases were dose‐dependent, but oxygen‐independent. Reactions in the dose range 6 to 25 Mrad (see footnote 2) appear to differ from those in the dose range 25 to 100 Mrad. Some suggested explanations are offered for these phenomena.