bluuebunny/crossref_metadata_2025 huggingface dataset:
CAN THE POOR COUNTRIES CATCH UP? MIXED RESULTS FROM EXTENDED SOURCES OF GROWTH PROJECTIONS FOR THE EARLY 21st CENTURY
Authors: Taylor Lance , Rada Codrina
Published: February 2007

Illustrative projections of per capita income gaps between two groups of developing economies and the rich economies for the period 1998–2030 are made on the basis of an extended sources of growth equation which accounts for interactions between trends in capital and labor productivity. The equation takes into consideration Kaldor–Verdoorn effects, possible impacts on labor productivity of trade liberalization and/or astute industrial policy, human and physical capital accumulation, employment and population growth, shifting shares of labor in income and traded goods in output, shifts in capital productivity, productivity growth retardation due to convergence and specific regional effects. Under optimistic assumptions about all these factors and in the historically unprecedented absence of adverse macroeconomic shocks over three decades, relative and absolute convergence of both regions to the rich countries may be possible.
Changing Headache from Preschool Age to Puberty. A Controlled Study
Authors: Virtanen R , Aromaa M , Rautava P , Metsähonkala L , Anttila P , Helenius H , Sillanpää M
Published: February 2007

The characteristics of disturbing primary headache and the occurrence of headache types were studied by sending a questionnaire to 1132 Finnish families of 6-year-old children. Children with headache in the preceding 6 months and their controls were clinically examined at the ages of 6 and 13. During the follow-up, half of the headaches, classified as migraine at age 6 years, were unchanged and 32% turned into tension-type headache. In children with tension-type headache, the situation was unchanged in 35%, and in 38% of children the headache type had changed to migraine. At preschool age the most common location of headache was bilateral and supraorbital, and at puberty bilateral and temporal. During the follow-up, symptoms concurrent with headache, such as odour phobia, dizziness and balance disturbances became more typical, whereas restlessness, flushing and abdominal symptoms became less marked. The early manifestation of both migraine and tension-type headache predict equally often migraine in puberty with marked changes in concurrent symptoms and pain localization.
A fresh start and the learning experience of ethnic minority entrepreneurs
Authors: Ekanem Ignatius , Wyer Peter
Published: February 2007

This paper focuses on ethnic minority entrepreneurs whose businesses failed within the first 3 years of trading, but were starting afresh with the help of the Brent Business Venture Fresh Start in Business programme. The paper aims to identify why the entrepreneurs had previously failed; what prompted them to start again; what was different about their business approach and practices second time around; and how key lessons had been learned as a result of their previous experiences that can improve their prospects for success in the future. The resultant insight derives out of an evaluation study of the Fresh Start programme, the methodology for which included initial telephone interviews with 20 ethnic minority entrepreneurs spread across eight business sectors, during which profile data were collected. The second phase of the study involved in‐depth face‐to‐face and semi‐structured interviews with the 20 entrepreneurs. The main findings suggest that failed entrepreneurs learn from their mistakes and actions embedded in the development processes and activities underpinning their first business venture attempt and are more successful second time around. The key learning processes and activities include learning from customer feedback, from interface with suppliers, from interaction with peers and from the fostering and facilitating inputs of provision such as the Fresh Start programme. The ability to learn by doing, problem‐solving and opportunity‐taking is important. The study concludes by highlighting key identified management capabilities which can improve the likelihood of new venture success, and in particular the value of giving future focus to the nature and form of effective strategic learning processes and activities that successful owner managers undertake and how these could be nurtured as part of the would‐be entrepreneurs’‘management capabilities tool box’.
Learning good judgement: young Europeans’ perceptions of key consumer skills
Authors: Schröder Monika J.A. , McKinnon Sabine
Published: February 2007

A convenience sample of 27 European Union (EU) citizens and two Romanians residing in the Scottish Central Belt took part in in‐depth interviews to explore a wide range of consumer decision‐making scenarios which ranged from borrowing and saving to impulse buying and ‘value for money’ choices. The aim of the research was to identify and assess how well educated young EU consumers perceive the consumer education process and the precise nature of consumption specific skills. Given the focus of the present paper on consumer judgement, the role of values received particular attention. The Schwartz Value Inventory served as a conceptual framework for analysing the responses. The results show that the family in its role as primary creator of values was considered the most important agent in the consumer education process because it establishes a routine pattern of decision making. Further support from social networks in the wider community and real‐life experience through trial and error were cited as equally significant for acquiring useful consumer skills. There was consensus that the influence of schools was limited to providing generic citizenship education rather than specific consumer studies classes. The findings of this study point to the need for changing the current focus of consumer education and consumer policy from an emphasis on training the vulnerable consumer to a more inclusive agenda which concentrates on value education for all market players including producers and marketers.
Histologic Comparison of Canine Skin Biopsies Collected Using Monopolar Electrosurgery, CO2 Laser, Radiowave Radiosurgery, Skin Biopsy Punch, and Scalpel
Authors: SILVERMAN EDWARD B. , READ ROBERT W. , BOYLE CAROLYN R. , COOPER ROBERT , MILLER WILLIAM W. , McLAUGHLIN RON M.
Published: February 2007

Objective— To compare the histologic appearance of canine skin biopsies collected by use of a scalpel, skin biopsy punch, monopolar electrosurgery, CO2 laser, and radio wave radiosurgery in fully rectified wave form (RWRS).

Study Design— Experimental, randomized design.

Animals— Healthy adult grayhounds (n=4).

Methods— Skin biopsies were collected using 5 techniques. Cut margins of biopsy specimens and adjacent peripheral skin were evaluated using light microscopy to compare penetration of the dermis by tissue carbonization (char).

Results— No char occurred in skin specimens collected by biopsy punch and scalpel. Char penetration occurred in all specimens collected by electrosurgery, CO2 laser, and RWRS. Mean char penetration in skin biopsies collected by RWRS (0.158 mm) was significantly less than for monopolar electrosurgery (0.223 mm) and CO2 laser (0.215 mm). Mean char penetration in adjacent peripheral skin surrounding biopsies collected by RWRS (0.171 mm) was significantly less than monopolar electrosurgery (0.255 mm) but not less than CO2 laser (0.215 mm, P<.07).

Conclusions— RWRS (blended waves in cut‐coagulate mode) caused less lateral thermal damage to canine skin biopsies than monopolar electrosurgery and CO2 laser and less lateral thermal injury to peripheral skin than monopolar electrosurgery.

Clinical Relevance— Excision of canine skin biopsies with heat‐generating devices may not allow reliable histologic interpretation, particularly when assessing margins of small biopsy specimens. RWRS may be less traumatic to canine skin than monopolar electrosurgery and CO2 laser when used to make incisions.
Evaluation of Two Dynamic Axial Fixators for Large Ruminants
Authors: SINGH GAJ RAJ , AITHAL HARI PRASAD , AMARPAL, MVSc, PhD  , KINJAVDEKAR PRAKASH , MAITI SWAPAN KUMAR , HOQUE MOZAMMEL , PAWDE ABHIJIT MOTIRAM , JOSHI HEM CHANDRA
Published: February 2007

Objectives—To evaluate healing of a radial osteotomy repaired by application of dynamic axial fixation devices (DAF) in large ruminants.

Study Design—In vivo study of bone healing after application of 2 DAF types. Model I had 2 sidebars, each with a central cylindrical cuff (internally threaded) with 2 detachable connecting rods telescoping within the cuff. Model II had 2 side bars with 2 moveable clamps with multiple holes.

Sample Population—Bull calves (n=8; aged, 1.5–2.0 years; weighing, 175–250 kg).

Methods—A mid‐diaphyseal radial osteotomy was repaired by use of a model I (n=4) or model II (n=4) DAF. Calves were monitored for weight bearing, stability of fixation, and radiographically for fracture reduction, alignment and healing at intervals for 6 months. Fixators were removed when there was radiographic evidence of healing.

Results—Both the fixators were well tolerated with free movement of adjacent joints. Fragment fixation was maintained until healing in all but 1 model I calf where failure occurred within 7 days. Model II DAF provided more rigid fixation as indicated by early full weight bearing and fracture healing with less callus formation. Functional recovery of repaired limbs occurred within 60 days in surviving calves.

Conclusions—Both bilateral DAFs were easy to apply; however, the model II DAF provided better fixation.

Clinical Relevance—The model II DAF made of low carbon steel was economical and may be useful for treating long bone fractures in large ruminants.
Tranylcypromine vs. lamotrigine in the treatment of refractory bipolar depression: a failed but clinically useful study
Authors: Nolen W. A. , Kupka R. W. , Hellemann G. , Frye M. A. , Altshuler L. L. , Leverich G. S. , Suppes T. , Keck P. E. , McElroy S. , Grunze H. , Mintz J. , Post R. M.
Published: February 2007

Objective:  To compare the efficacy and tolerability of tranylcypromine vs. lamotrigine in bipolar depression not responding to conventional antidepressants.

Method:  Bipolar depressed patients received open randomized treatment with tranylcypromine or lamotrigine as add‐on to a mood stabilizer during 10 weeks. In a second treatment phase, non‐responding patients could receive the opposite drug. Outcome criteria were response (measured with CGI‐BP and IDS‐C), switch into mania, and completion of the study.

Results:  Only 20 of 70 planned patients were randomized, due to problems with recruitment, and 19 patients received any medication. During the first treatment phase 5/8 patients (62.5%) responded to tranylcypromine without switch into mania, compared with 4/11 patients (36.4%) on lamotrigine with two switches (statistically not significant). Over both treatment phases, 8/10 patients (80%) receiving tranylcypromine completed the study vs. 5/13 (38.5%) on lamotrigine (likelihood 0.02).

Conclusion:  There still appears to be a role for tranylcypromine in the treatment of refractory bipolar depression. Larger controlled studies are demanded.
Laryngeal dyskinesia: An under‐recognized condition
Authors: Lawrence Sean G
Published: February 2007

Objective:  To perform a review of the epidemiology, pathogenesis, clinical presentation, diagnosis and management of laryngeal dyskinesia.

Methods:  A search of the Medline database from 1966 to 2003 was performed. A manual search was performed of the references of each article.

Results:  Laryngeal dyskinesia is a respiratory condition characterized by abnormal vocal cord adduction and airflow limitation at the level of the larynx in the absence of evidence of local organic disease. It typically presents to the ED as wheeze, stridor or apparent upper airway obstruction. It occurs across a wide age range, is more common in females, and is typically associated with a range of underlying psychopathologies. Diagnosis is often delayed and unnecessary emergency treatment such as intubation and tracheostomy is not uncommon. Patients are commonly on high‐dose steroids and are frequent users of the health‐care system, often over prolonged periods. There are multiple diagnostic features on history and examination, and flexible nasendoscopy of the vocal cords in the ED can be used to confirm the diagnosis. Treatment options in the ED include sedation and use of continuous positive airway pressure. Long‐term treatment involves a multidisciplinary approach involving respiratory physicians/ear, nose and throat surgeons, speech therapy and psychiatry.

Conclusion:  Laryngeal dyskinesia remains an under‐appreciated cause of respiratory presentations to the ED. Emergency physicians are ideally placed to make the diagnosis and initiate appropriate referral for specific therapies that have a high level of success.
Colonization Strategies of Two Liana Species in a Tropical Dry Forest Canopy
Authors: Avalos Gerardo , Mulkey Stephen S. , Kitajima Kaoru , Wright S. Joseph
Published: February 2007

Lianas impose intense resource competition for light in the upper forest canopy by displaying dense foliage on top of tree crowns. Using repeated access with a construction crane, we studied the patterns of canopy colonization of the lianas Combretum fruticosum and Bonamia trichantha in a Neotropical dry forest in Panama. Combretum fruticosum flushed leaves just before the rainy season, and its standing leaf area quickly reached a peak in the early rainy season (May–June). In contrast, B. trichantha built up foliage area continuously throughout the rainy season and reached a peak in the late rainy season (November). Both species displayed the majority of leaves in full sun on the canopy surface, but C. fruticosum displayed a greater proportion of leaves (26%) in more shaded microsites than B. trichantha (12%). Self‐shading within patches of liana leaves within the uppermost 40–50 cm of the canopy reduced light levels measured with photodiodes placed directly on leaves to 4–9 percent of light levels received by sun leaves. Many leaves of C. fruticosum acclimated to shade within a month following the strongly synchronized leaf flushing and persisted in deep shade. In contrast, B. trichantha produced short‐lived leaves opportunistically in the sunniest locations. Species differences in degree of shade acclimation were also evident in terms of structural (leaf mass per area, and leaf toughness) and physiological characters (nitrogen content, leaf life span, and light compensation point). Contrasting leaf phenologies reflect differences in light exploitation and canopy colonization strategies of these two liana species.
Neuropathologic Contributions to Understanding AIDS and the Central Nervous System
Authors: Scaravilli Francesco , Bazille Céline , Gray Françoise
Published: February 2007

This historical review describes the evolution of the pathogenetic concepts associated with infection by the Human Immunodeficiency Virus (HIV), with emphasis on the pathology of the nervous system. Although the first descriptions of damage to the nervous system in the acquired immunodeficiency syndrome (AIDS) only appeared in 1982, the dramatic diffusion of the epidemic worldwide and the invariably rapidly fatal outcome of the disease, before the introduction of efficient treatment, generated from the beginning an enormous amount of research with rethinking on a number of pathogenetic concepts. Less than 25 years after the first autopsy series of AIDS patients were published and the virus responsible for AIDS was identified, satisfactory definition and classification of a number of neuropathological complications of HIV infection have been established, leading to accurate clinical radiological and biological diagnosis of the main neurological complications of the disease, which remain a major cause of disability and death in AIDS patients. Clinical and experimental studies have provided essential insight into the pathogenesis of CNS lesions and natural history of the disease. The relatively recent introduction of highly active antiretroviral therapy (HAART) in 1995–1996 has dramatically improved the course and prognosis of HIV disease. However, there remain a number of unsolved pathogenetic issues, the most puzzling of which remains the precise mechanism of neuronal damage underlying the specific HIV‐related cognitive disorders (HIV dementia). In addition, although HAART has changed the course of neurological complications of HIV infection, new issues have emerged such as the lack of improvement or even paradoxical deterioration of the neurological status in treated patients. Interpretation of these latter data remains largely speculative partly because of the small number of neuropathological studies related to the beneficial consequence of this treatment.
Franklin's Civic Science
Authors: Dylla H. Frederick
Published: February 2007

The First Scientific American Benjamin Franklin and the Pursuit of Genius
.
By Joyce E. Chaplin
. Basic Books (Perseus Books Group), New York, 2006. 431 pp. $27.50, C$37.50. ISBN 9780465009558.

While she does not ignore Franklin's accomplishments as a printer, revolutionary, diplomat, and statesman, Chaplin devotes most of her efforts to considering the variety and scope of her subject's scientific activities.
Development of a Sensitive and Specific Enzyme-Linked Immunosorbent Assay Based on Recombinant Antigens for Rapid Detection of Antibodies against
Mycoplasma agalactiae
in Sheep
Authors: Fusco Marisa , Corona Lucia , Onni Toniangelo , Marras Elisabetta , Longheu Carla , Idini Graziano , Tola Sebastiana
Published: February 2007

We developed a new recombinant enzyme-linked immunosorbent assay (rELISA) for serodiagnosis of contagious agalactia (CA), a disease caused by
Mycoplasma agalactiae
in sheep and goats. The assay is based on two
M. agalactiae
surface proteins, namely, P80 and P55. Identification of these immunodominant and common antigens was accomplished by examining the antibody response elicited in sheep during experimental infection and comparing it to the protein expression profiles of 75
M. agalactiae
field strains. Our rELISA was tested with 343 sera, collected from sheep with a laboratory-confirmed diagnosis of CA (
n
= 223) and from healthy animals (
n
= 120). All sera had previously been tested by Western blotting (WB) for reactivity against
M. agalactiae
. In addition, our rELISA was compared with a commercial routine ELISA based on inactivated antigens (CHEKiT). Among the 223 samples that were WB positive for
M. agalactiae
, 209 (93.7%) tested positive for rP80-P55 with our ELISA, whereas only 164 (73.8%) tested positive with the CHEKiT ELISA. Among the 120 samples tested that were WB negative for
M. agalactiae
, 96.7% were confirmed as negative with our rELISA, while only 75.8% were confirmed as negative with the CHEKiT ELISA. A comparison of the results with receiver operating characteristic curves indicated that the differences observed between our rELISA and the CHEKiT ELISA are statistically significant. The use of recombinant peptides instead of inactivated antigens could significantly improve the discrimination of positive and negative animals, bringing significant advantages in controlling the import/export of live animals and helping in eradication of this economically detrimental disease.
Detection of Genes Encoding Internalization-Associated Proteins in
Streptococcus pyogenes
Isolates from Patients with Invasive Diseases and Asymptomatic Carriers
Authors: Baldassarri Lucilla , Creti Roberta , Imperi Monica , Recchia Simona , Pataracchia Marco , Orefici Graziella
Published: February 2007

A total of 161
Streptococcus pyogenes
isolates from patients with invasive infections or from asymptomatic carriers were examined for genes (
prtF1
,
prtF2
, and
fba
) coding for fibronectin-binding proteins to evaluate their involvement in the pathogenesis of different streptococcal manifestations. We found no significant differences in the presence of these three genes between the two groups. Overall, the
prtF2
gene was present in similar percentages among strains from both sources (61% versus 63%). Strains carrying the gene
fba
were slightly more common among those isolated from asymptomatic carriers (72.6% versus 65%). Also, the
prtF1
gene was present in a higher, but not significant, percentage among strains from throat swabs than among isolates from invasive infections (75% versus 64.9%). However, this more detailed characterization of the genes encoding fibronectin-binding proteins allowed us to identify a strong association of genes of the
erm
class, coding for macrolide resistance, with
prtF1
and
prtF2
rather than with
prtF1
alone. Since macrolide resistance was significantly associated with throat swab isolates, it may be hypothesized that proteins coded by
prtF1
and
prtF2
genes may be synergic in providing support for cell invasion and/or colonizing or persistence efficiency.
A Prospective, Randomized, Double-Blind Study of Vaginal Microflora and Epithelium in Women Using a Tampon with an Apertured Film Cover Compared with Those in Women Using a Commercial Tampon with a Cover of Nonwoven Fleece
Authors: Chase David J. , Schenkel Berenike P. , Fahr Anne-Marie , Eigner Ulrich
Published: February 2007

Healthy women with normal menstrual cycles were randomly assigned to use either a test tampon during cycle 1 and a reference tampon during cycle 2 or a reference tampon during cycle 1 and a test tampon during cycle 2. Tampons were identical except for their cover materials: apertured film for the test tampon and nonwoven fleece for the reference tampon. Product use was doubly blinded. Qualitative and quantitative analyses of vaginal cultures were done pre-, mid-, and postmenstrually for a broad panel of microorganisms, colposcopy was performed, and diary reports were collected; 101 of 105 enrolled subjects completed the study. Midmenstrual findings for a variety of organisms differed from pre- and postmenstrual observations whether subjects were using test or reference tampons. No statistically significant differences were noted in prevalence or colony counts at premenstrual versus mid- and postmenstrual visits for most microorganisms. Prevalences of
Gardnerella
and anaerobic gram-negative rods were significantly different between tampons at the premenstrual visit, when unusually low values were observed for the test and reference tampons, respectively. None of the changes or differences in microflora were considered to be clinically significant. It is noteworthy, however, that declines in the prevalence and abundance of
Lactobacillus
during the menstrual periods were less pronounced during the use of both test and reference tampons than those reported from previous studies. Colposcopy showed no abnormal findings with either tampon and no changes in vaginal or cervical epithelial integrity. Thus, all evidence from both microbiological and colposcopic evaluations indicates that the apertured film cover of the test tampon is as safe as the nonwoven cover of the reference tampon.
Determination of Kaposi's Sarcoma-Associated Herpesvirus C-Terminal Latency-Associated Nuclear Antigen Residues Mediating Chromosome Association and DNA Binding
Authors: Kelley-Clarke Brenna , Ballestas Mary E. , Srinivasan Viswanathan , Barbera Andrew J. , Komatsu Takashi , Harris Te-Ana , Kazanjian Mia , Kaye Kenneth M.
Published: February 2007

Kaposi's sarcoma-associated herpesvirus latency-associated nuclear antigen (LANA) tethers viral terminal repeat (TR) DNA to mitotic chromosomes to mediate episome persistence. The 1,162-amino-acid LANA protein contains both N- and C-terminal chromosome attachment regions. The LANA C-terminal domain self-associates to specifically bind TR DNA and mitotic chromosomes. Here, we used alanine scanning substitutions spanning residues 1023 to 1145 to investigate LANA self-association, DNA binding, and C-terminal chromosome association. No residues were essential for LANA oligomerization, as assayed by coimmunoprecipitation experiments, consistent with redundant roles for amino acids in self-association. Different subsets of amino acids were important for DNA binding, as assayed by electrophoretic mobility shift assay, and mitotic chromosome association, indicating that distinct C-terminal LANA subdomains effect DNA and chromosome binding. The DNA binding domains of LANA and EBNA1 are predicted to be structurally homologous; certain LANA residues important for DNA binding correspond to those with roles in EBNA1 DNA binding, providing genetic support for at least partial structural homology. In contrast to the essential role of N-terminal LANA chromosome targeting residues in DNA replication, deficient C-terminal chromosome association did not reduce LANA-mediated DNA replication.
Induction of Endoplasmic Reticulum Stress in Thymic Lymphocytes by the Envelope Precursor Polyprotein of a Murine Leukemia Virus during the Preleukemic Period
Authors: Yoshimura Fayth K. , Luo Xixia
Published: February 2007

Infection of thymic lymphocytes by a mink cell focus-forming murine leukemia virus induces apoptosis during the preleukemic period of lymphomagenesis. In this study, we observed that during this period, the viral envelope precursor polyprotein accumulated to high levels in thymic lymphocytes from mice inoculated with virus. Envelope accumulation occurred with the same kinetics as the induction of endoplasmic reticulum (ER) stress, which resulted in the upregulation of the 78-kDa glucose-regulated protein (GRP78). In thymic lymphomas, GRP78 levels were higher than those in virus-infected preleukemic cells, and GRP58 was upregulated. These results suggest that Env precursor accumulation induces ER stress, which participates in thymic lymphocyte apoptosis. The subsequent upregulation of ER chaperone proteins GRP78 and GRP58 may contribute to rescuing cells from virus-induced apoptosis.
Intramolecular amidation — An efficient synthesis of 3-aryl-2-quinolinones
Authors: Luo Yinggang , Tao Feiyan , Liu Yan , Li Bogang , Zhang Guolin
Published: February 2007

To reveal the scope of the syntheses of 3-aryl-2-quinolinones from 2-nitro-α-phenylcinnamic acids, the isomerization of (E)-2-amino-α-phenylcinnamic acids was studied. The results showed that (E)-2-amino-α-phenylcinnamic acids were isomerized to its (Z)-forms under sunlight in organic solvents. The reaction temperature and the functional groups at both phenyl rings have no effect on the isomerization of (E)-2-amino-α-phenylcinnamic acids and the following intramolecular spontaneous amidation of (Z)-2-amino-α-phenylcinnamic acids. Various 3-aryl-2-quinolinones prepared in high total yields indicated that the syntheses of 3-aryl-2-quinolinones from Perkin condensation products 2-nitro-α-phenylcinnamic acids via reduction, sunlight-induced isomerization of (E)-2-amino-α-phenylcinnamic acids, and the following intramolecular amidation is an efficient procedure. Key words: 3-aryl-2-quinolinones, isomerization, amidation.
Scaled quantum mechanical force fields for trifluoromethyl selenium derivatives. I. The CF3SeCN and CF3SeCH3 molecules
Authors: Fernández L E , Varetti E L
Published: February 2007

Force fields and vibrational properties were calculated for the trifluoromethyl selenium derivatives, CF3SeCN and CF3SeCH3, by means of density functional theory (DFT) techniques. The existing experimental data and assignments for these molecules were confirmed by the theoretical results. These data were subsequently used in the definition of scaled quantum mechanical force fields for such chemical species. The obtained force constants are compared with results previously published for similar compounds.Key words: trifluoromethyl selenium, force constants, structure, DFT calculation.
Effect of N-cetyl-N,N,N-trimethylammonium bromide and orthophenylenediamine on the corrosion inhibition of carbon steel in 1 mol/L HCl
Authors: Babu B Ramesh , Parande A K , Ramasamy P L
Published: February 2007

Inhibition studies of N-cetyl-N,N,N-trimethylammonium bromide (CTAB) and orthophenylenediamine (OPD) have shown that they were effective inhibitors of corrosion of carbon steel in HCl. The inhibitive behaviour of OPD with CTAB on the corrosion of carbon steel in 1 mol/L HCl was studied by gravimetric weight loss, potentiodynamic polarization, and electrochemical impedance measurements. Inhibition efficiency (IE) was found to increase with the increase in concentration of CTAB and it was also found that CTAB was effective only when used above a concentration of 100 mmol/L. Furthermore, the addition of 20 mmol/L of OPD to CTAB slightly increased the IE. The adsorption of these compounds on carbon steel in 1 mol/L HCl obeyed Langmuir's adsorption isotherm. These inhibitors reduced the permeation current. The IE was observed as high for 200 mmol/L of CTAB with 20 mmol/L of OPD in all the techniques studied. Scanning electron microscopy clearly showed that the inhibition was due to a polymolecular film formed by the physical adsorption of the inhibitor on the metal surface.Key words: carbon steel, corrosion, inhibitors, impedance, potentiodynamic polarization.
Diastereoselective addition of chlorotitanium enolates of N-acyl thiazolidinethione to activated imines — A novel synthesis of β-lactams
Authors: Herold-Dublin Marike , Liotta Dennis C
Published: February 2007

We report a novel methodology for preparing enantiomerically pure β-lactams, starting from nitriles in diastereomeric ratios up to 10:1. The power of the methodology was demonstrated by the efficient synthesis of the cholesterol absorption inhibitor SCH 48462.Key words: β-lactam, N-metalloaldimine, titanium Lewis acids, cholesterol absorption inhibitor.
ROS scavenging before 27°C ischemia protects hearts and reduces mitochondrial ROS, Ca2+ overload, and changes in redox state
Authors: Camara Amadou K. S. , Aldakkak Mohammed , Heisner James S. , Rhodes Samhita S. , Riess Matthias L. , An JiangZhong , Heinen André , Stowe David F.
Published: February 2007

We have shown that cold perfusion of hearts generates reactive oxygen and nitrogen species (ROS/RNS). In this study, we determined 1) whether ROS scavenging only during cold perfusion before global ischemia improves mitochondrial and myocardial function, and 2) which ROS leads to compromised cardiac function during ischemia and reperfusion (I/R) injury. Using fluorescence spectrophotometry, we monitored redox balance (NADH and FAD), O2•− levels and mitochondrial Ca2+ (m[Ca2+]) at the left ventricular wall in 120 guinea pig isolated hearts divided into control (Con), MnTBAP (a superoxide dismutase 2 mimetic), MnTBAP (M) + catalase (C) + glutathione (G) (MCG), C+G (CG), and NG-nitro-l-arginine methyl ester (l-NAME; a nitric oxide synthase inhibitor) groups. After an initial period of warm perfusion, hearts were treated with drugs before and after at 27°C. Drugs were washed out before 2 h at 27°C ischemia and 2 h at 37°C reperfusion. We found that on reperfusion the MnTBAP group had the worst functional recovery and largest infarction with the highest m[Ca2+], most oxidized redox state and increased ROS levels. The MCG group had the best recovery, the smallest infarction, the lowest ROS level, the lowest m[Ca2+], and the most reduced redox state. CG and l-NAME groups gave results intermediate to those of the MnTBAP and MCG groups. Our results indicate that the scavenging of cold-induced O2•− species to less toxic downstream products additionally protects during and after cold I/R by preserving mitochondrial function. Because MnTBAP treatment showed the worst functional return along with poor preservation of mitochondrial bioenergetics, accumulation of H2O2 and/or hydroxyl radicals during cold perfusion may be involved in compromised function during subsequent cold I/R injury.
Salutary effects of 17β-estradiol on T-cell signaling and cytokine production after trauma-hemorrhage are mediated primarily via estrogen receptor-α
Authors: Suzuki Takao , Shimizu Tomoharu , Yu Huang-Ping , Hsieh Ya-Ching , Choudhry Mashkoor A. , Chaudry Irshad H.
Published: February 2007

Although 17β-estradiol (E2) administration following trauma-hemorrhage prevents the suppression in splenocyte cytokine production, it remains unknown whether the salutary effects of 17β-estradiol are mediated via estrogen receptor (ER)-α or ER-β. Moreover, it is unknown which signaling pathways are involved in 17β-estradiol's salutary effects. Utilizing an ER-α- or ER-β-specific agonist, we examined the role of ER-α and ER-β in E2-mediated restoration of T-cell cytokine production following trauma-hemorrhage. Moreover, since MAPK, NF-κB, and activator protein (AP)-1 are known to regulate T-cell cytokine production, we also examined the activation of MAPK, NF-κB, and AP-1. Male rats underwent trauma-hemorrhage (mean arterial pressure 40 mmHg for 90 min) and fluid resuscitation. ER-α agonist propyl pyrazole triol (PPT; 5 μg/kg), ER-β agonist diarylpropionitrile (DPN; 5 μg/kg), 17β-estradiol (50 μg/kg), or vehicle (10% DMSO) was injected subcutaneously during resuscitation. Twenty-four hours thereafter, splenic T cells were isolated, and their IL-2 and IFN-γ production and MAPK, NF-κB, and AP-1 activation were measured. T-cell IL-2 and IFN-γ production was decreased following trauma-hemorrhage, and this was accompanied with a decrease in T-cell MAPK, NF-κB, and AP-1 activation. PPT or 17β-estradiol administration following trauma-hemorrhage normalized those parameters, while DPN administration had no effect. Since PPT, but not DPN, administration following trauma-hemorrhage was as effective as 17β-estradiol in preventing the T-cell suppression, it appears that ER-α plays a predominant role in mediating the salutary effects of 17β-estradiol on T cells following trauma-hemorrhage, and that such effects are likely mediated via normalization of MAPK, NF-κB, and AP-1 signaling pathways.
Optical Recording of Action Potentials and Other Discrete Physiological Events: A Perspective from Signal Detection Theory
Authors: Sjulson Lucas , Miesenböck Gero
Published: February 2007

Optical imaging of physiological events in real time can yield insights into biological function that would be difficult to obtain by other experimental means. However, the detection of all-or-none events, such as action potentials or vesicle fusion events, in noisy single-trial data often requires a careful balance of tradeoffs. The analysis of such experiments, as well as the design of optical reporters and instrumentation for them, is aided by an understanding of the principles of signal detection. This review illustrates these principles, using as an example action potential recording with optical voltage reporters.
Protein Kinase CK2α as an Unfavorable Prognostic Marker and Novel Therapeutic Target in Acute Myeloid Leukemia
Authors: Kim Jin Seok , Eom Ju In , Cheong June-Won , Choi Ae Jin , Lee Jin Koo , Yang Woo Ick , Min Yoo Hong
Published: February 2007

Introduction: Protein kinase CK2 is implicated in cellular proliferation and transformation. However, the clinical and biological significances of CK2 have not been elucidated in acute myeloid leukemia (AML).

Experimental Design: We evaluated the biological significances of catalytic subunit of CK2 (CK2α) expression in leukemia cell lines and primary leukemic blasts obtained from AML patients.

Results: In this study, the expression of CK2α was elevated in a substantial proportion of AML. In AML patients with normal karyotype, the disease-free survival and overall survival rates were significantly lower in the CK2α-high compared with the CK2α-low AML cases (P = 0.0252 and P = 0.0392, respectively). An induced overexpression of CK2α increased the levels of Ser473 phosphorylated (p)-Akt/protein kinase B (PKB), p-PDK1, pFKHR, p-BAD, Bcl-2, Bcl-xL, Mcl-1, and XIAP. Treatment of U937 cell line and primary AML blasts with selective CK2 inhibitor, tetrabromobenzotriazole or apigenin, reduced the levels of these molecules in a dose-dependent manner. CK2α small interfering RNA treatment also resulted in a down-regulation of p-Akt/PKB and Bcl-2 in U937 cells. Apigenin-induced cell death was preferentially observed in the CK2α-high leukemia cell lines, HL-60 and NB4, which was accompanied by cytoplasmic release of SMAC/DIABLO and proteolytic cleavage of procaspase-9, procaspase-3, procaspase-8, and poly(ADP)ribose polymerase. An induced overexpression of CK2α potentially enhanced the sensitivity of U937 cells to the apigenin-induced cell death. Apigenin-induced cell death was significantly higher in CK2α-high AML compared with CK2α-low AML (P < 0.0001) or normal bone marrow samples (P < 0.0001).

Conclusion: These findings strongly suggest protein kinase CK2α as an unfavorable prognostic marker and novel therapeutic target in AML.
Implications of Endocrine Gland–Derived Vascular Endothelial Growth Factor/Prokineticin-1 Signaling in Human Neuroblastoma Progression
Authors: Ngan Elly S.W. , Sit Francesco Y.L. , Lee King Liu , Miao Xiaoping , Yuan Zhengwei , Wang Weilin , Nicholls John M. , Wong Kenneth K.Y. , Garcia-Barcelo Mercè , Lui Vincent C.H. , Tam Paul K.H.
Published: February 2007

Purpose: Neuroblastoma is a common pediatric tumor that is derived from improperly differentiated neural crest cells (NCC). We recently revealed that endocrine gland–derived vascular endothelial growth factor/prokineticin-1 (EG-VEGF/Prok-1) is a key factor mediating the growth and differentiation of enteric NCCs during development. In this report, we further elucidate its role in neuroblastoma progression.

Experimental Design: We studied the expression and copy number of EG-VEGF/Prok-1 receptors (PK-R1 and PK-R2) in 26 neuroblastoma tumors by real-time reverse transcription-PCR and immunohistochemical analysis. Implication of EG-VEGF/Prok-1 signaling in neuroblastoma progression was further shown in a neuroblastoma cell line (SK-N-SH).

Results: We found that all neuroblastoma samples from stages II to IV expressed both PK-R1 and PK-R2. Kruskall-Wallis signed rank tests revealed that the expression level of PK-R1 transcript is associated with the stages and metastasis of the neuroblastoma (P < 0.05), and PK-R2 is persistently higher in advanced-stage neuroblastoma samples. About 38% of the neuroblastoma tumors (10:26) possessed MYCN amplification, whereas no PK-R1 and PK-R2 amplifications were detected, suggesting that the overexpression of the receptors was not due to gene amplification. Subsequent functional studies showed that EG-VEGF/Prok-1 activates the Akt pathway to induce the proliferation of neuroblastoma cells. Targeted down-regulation studies revealed that EG-VEGF/Prok-1–mediated proliferation requires the presence of these two receptors, and that PK-R2 is essential for inhibiting apoptosis. In vitro migration and invasion assays also indicated that EG-VEGF/Prok-1 significantly enhances the cell migration/invasion of SK-N-SH.

Conclusions: Our study has shown for the first time that aberrant EG-VEGF/Prok-1 signaling favors neuroblastoma progression and could be a potential target for future neuroblastoma treatment.
Phylogenetic signal and functional categories in Proteobacteria genomes
Authors: Comas Iñaki , Moya Andrés , González-Candelas Fernando
Published: February 2007

Background

A comprehensive evolutionary analysis of bacterial genomes implies to identify the hallmark of vertical and non-vertical signals and to discriminate them from the presence of mere phylogenetic noise. In this report we have addressed the impact of factors like the universal distribution of the genes, their essentiality or their functional role in the cell on the inference of vertical signal through phylogenomic methods.

Results

We have established that supermatrices derived from data sets composed mainly by genes suspected to be essential for bacterial cellular life perform better on the recovery of vertical signal than those composed by widely distributed genes. In addition, we show that the "Transcription" category of genes seems to harbor a better vertical signal than other functional categories. Moreover, the "Poorly characterized" category performs better than other categories related with metabolism or cellular processes.

Conclusion

From these results we conclude that different data sets allow addressing different questions in phylogenomic analyses. The vertical signal seems to be more present in essential genes although these also include a significant degree of incongruence. From a functional perspective, as expected, informational genes perform better than operational ones but we have also shown the surprising behavior of poorly annotated genes, which points to their importance in the genome evolution of bacteria.
Deconstructing evolution of adult phenotypes: genetic analyses ofkitreveal homology and evolutionary novelty during adult pigment pattern development ofDaniofishes
Authors: Mills Margaret G. , Nuckels Richard J. , Parichy David M.
Published: February 2007

The cellular bases for evolutionary changes in adult form remain largely unknown. Pigment patterns of Danio fishes are a convenient system for studying these issues because of their diversity and accessibility and because one species, the zebrafish D. rerio, is a model organism for biomedical research. Previous studies have shown that in zebrafish, stripes form by migration and differentiation of distinct populations of melanophores:early metamorphic (EM) melanophores arise widely dispersed and then migrate into stripes, whereas late metamorphic (LM) melanophores arise already within stripes. EM melanophores require the kit receptor tyrosine kinase, as kit mutants lack these cells but retain LM melanophores, which form a residual stripe pattern. To see if similar cell populations and genetic requirements are present in other species, we examined D. albolineatus, which has relatively few, nearly uniform melanophores. We isolated a D. albolineatus kit mutant and asked whether residual, LM melanophores develop in this species, as in D. rerio. We found that kit mutant D. albolineatus lack EM melanophores, yet retain LM melanophores. Histological analyses further show that kitfunctions during a late step in metamorphic melanophore development in both species. Interestingly, kit mutant D. albolineatus develop a striped melanophore pattern similar to kit mutant D. rerio,revealing latent stripe-forming potential in this species, despite its normally uniform pattern. Comparisons of wild types and kit mutants of the two species further show that species differences in pigment pattern reflect: (1) changes in the behavior of kit-dependent EM melanophores that arise in a dispersed pattern and then migrate into stripes in D. rerio, but fail to migrate in D. albolineatus; and (2) a change in the number of kit-independent LM melanophores that arise already in stripes and are numerous in D. rerio, but few in D. albolineatus. Our results show how genetic analyses of a species closely related to a biomedical model organism can reveal both conservatism and innovation in developmental mechanisms underlying evolutionary changes in adult form.
Mbd3, a component of the NuRD co-repressor complex, is required for development of pluripotent cells
Authors: Kaji Keisuke , Nichols Jennifer , Hendrich Brian
Published: February 2007

Mbd3 is a core component of the NuRD (Nucleosome Remodeling and Histone Deacetylation) co-repressor complex, and NuRD-mediated silencing has been implicated in cell fate decisions in a number of contexts. Mbd3-deficient embryonic stem (ES) cells made by gene targeting are viable but fail to form a stable NuRD complex, are severely compromised in the ability to differentiate,and show LIF-independent self-renewal. Mbd3 is known to be essential for postimplantation embryogenesis in mice, but the function of Mbd3 in vivo has not previously been addressed. Here we show that the inner cell mass (ICM) of Mbd3-deficient blastocysts fails to develop into mature epiblast after implantation. Unlike Mbd3-null ES cells, Mbd3-deficient ICMs grown ex vivo fail to expand their Oct4-positive, pluripotent cell population despite producing robust endoderm outgrowths. Additionally, we identify a set of genes showing stage-specific expression in ICM cells during preimplantation development, and show that Mbd3 is required for proper gene expression patterns in pre- and peri-implantation embryos and in ES cells. These results demonstrate the importance of Mbd3/NuRD for the development of pluripotent cells in vivo and for their ex vivo progression into embryonic stem cells, and highlight the differences between ES cells and the ICM cells from which they are derived.
Analysis of a Triple Testcross Design With Recombinant Inbred Lines Reveals a Significant Role of Epistasis in Heterosis for Biomass-Related Traits in Arabidopsis
Authors: Kusterer Barbara , Muminovic Jasmina , Utz H Friedrich , Piepho Hans-Peter , Barth Susanne , Heckenberger Martin , Meyer Rhonda C , Altmann Thomas , Melchinger Albrecht E
Published: February 2007

Primary causes of heterosis are still unknown. Our goal was to investigate the extent and underlying genetic causes of heterosis for five biomass-related traits in Arabidopsis thaliana. We (i) investigated the relative contribution of dominance and epistatic effects to heterosis in the hybrid C24 × Col-0 by generation means analysis and estimates of variance components based on a triple testcross (TTC) design with recombinant inbred lines (RILs), (ii) estimated the average degree of dominance, and (iii) examined the importance of reciprocal and maternal effects in this cross. In total, 234 RILs were crossed to parental lines and their F1's. Midparent heterosis (MPH) was high for rosette diameter at 22 days after sowing (DAS) and 29 DAS, growth rate (GR), and biomass yield (BY). Using the F2-metric, directional dominance prevailed for the majority of traits studied but reciprocal and maternal effects were not significant. Additive and dominance variances were significant for all traits. Additive × additive and dominance × dominance variances were significant for all traits but GR. We conclude that dominance as well as digenic and possibly higher-order epistatic effects play an important role in heterosis for biomass-related traits. Our results encourage the use of Arabidopsis hybrid C24 × Col-0 for identification and description of quantitative trait loci (QTL) for heterosis for biomass-related traits and further genomic studies.
El Amor Y La Salvación Existencial En Dos Poemas De Pedro Salinas
Authors: Villegas Por Juan
Published: February 2007

The recurrent euphoria of the lyric speaker who addresses the mysterious beloved in La voz a ti debida establishes love as the keynote of the work. The poet strives for and falls in love with love itself. Reacting against a tangible world which has no meaning for him, he seeks instead the mysterious and the ineffable, musing on his beloved's reality, searching for that reality, and struggling against a void. This conception of love is manifest in the theme, structure, and images of each poem. In the first verse, “Cuando tu me eligiste” the three moments–before (chaos and confusion), now (vital plenitude and enthusiasm) and after (deception and return to gray uniformity) –are distinguished by varying images and poetic tones. Joy is dominant in the second offering, “Qué alegría vivir / sintiendose vivido!” and is thematically justified because the lyricist's amorous fulfillment prevents the anguish of nothingness and the threat of death, and affirms love's power. The poem's structure is parallelistic, based on the two types of existence. His is unreal and banal; hers is real and meaningful. The movement of the poem leads to the joining together of the lover and the beloved and culminates in their mystic union at the poem's center. The images are ethereal and provide an example of a “poetics of verticality.” (In Spanish)