bluuebunny/crossref_metadata_2025 huggingface dataset:
In Vivo Bipartite Interaction Between the Hsp40 Sis1 and Hsp70 in Saccharomyces cerevisiae
Authors: Aron Rebecca , Lopez Nelson , Walter William , Craig Elizabeth A , Johnson Jill
Published: February 2005

The essential Hsp40, Sis1, is a J-protein cochaperone for the Ssa class of Hsp70's of Saccharomyces cerevisiae. Sis1 is required for the maintenance of the prion [RNQ+], as Sis1 lacking its 55-amino-acid glycine-rich region (G/F) does not maintain [RNQ+]. We report that overexpression of Sis1ΔG/F in an otherwise wild-type strain had a negative effect on both cell growth and [RNQ+] maintenance, while overexpression of wild-type Sis1 did not. Overexpression of the related Hsp40 Ydj1 lacking its G/F region did not cause inhibition of growth, indicating that this dominant effect of Sis1ΔG/F is not a characteristic shared by all Hsp40's. Analysis of small deletions within the SIS1 G/F region indicated that the observed dominant effects were caused by the absence of sequences known to be important for Sis1's unique cellular functions. These inhibitory effects of Sis1ΔG/F were obviated by alterations in the N-terminal J-domain of Sis1 that affect interaction with Ssa's ATPase domain. In addition, a genetic screen designed to isolate additional mutations that relieved these inhibitory effects identified two residues in Sis1's carboxy-terminal domain. These alterations disrupted the interaction of Sis1 with the 10-kD carboxy-terminal regulatory domain of Ssa1, indicating that Sis1 has a bipartite interaction with Ssa in vivo.
Ty1 Copy Number Dynamics in Saccharomyces
Authors: Garfinkel David J , Nyswaner Katherine M , Stefanisko Karen M , Chang Caroline , Moore Sharon P
Published: February 2005

To understand long terminal repeat (LTR)-retrotransposon copy number dynamics, Ty1 elements were reintroduced into a “Ty-less” Saccharomyces strain where elements had been lost by LTR-LTR recombination. Repopulated strains exhibited alterations in chromosome size that were associated with Ty1 insertions, but did not become genetically isolated. The rates of element gain and loss under genetic and environmental conditions known to affect Ty1 retrotransposition were determined using genetically tagged reference elements. The results show that Ty1 retrotransposition varies with copy number, temperature, and cell type. In contrast to retrotransposition, Ty1 loss by LTR-LTR recombination was more constant and not markedly influenced by copy number. Endogenous Ty1 cDNA was poorly utilized for recombination when compared with LTR-LTR recombination or ectopic gene conversion. Ty1 elements also appear to be more susceptible to copy number fluctuation in haploid cells. Ty1 gain/loss ratios obtained under different conditions suggest that copy number oscillates over time by altering the rate of retrotransposition, resulting in the diverse copy numbers observed in Saccharomyces.
Hypothyroxinemia in Mechanically Ventilated Term Infants Is Associated With Increased Use of Rescue Therapies
Authors: Lim Doyle J. , Herring Michelle Kantor , Leef Kathleen H. , Getchell Jane , Bartoshesky Louis E. , Paul David A.
Published: February 2005

Objective. Although common in preterm infants, transient hypothyroxinemia (TH) has not been investigated extensively in ill term infants. The objectives of this study were to investigate serum thyroxine (T4) and thyroid-stimulating hormone (TSH) in sick term infants and to determine whether there is any association between measures of thyroid function and short-term outcome in term infants who receive mechanical ventilation.

Methods. The investigation consisted of both a prospective observational study and a retrospective cohort study. In the prospective study, T4 and TSH were measured after birth in a group of sick term infants (n = 38) and compared with a group of well term infants (n = 18). Infants in the sick group received mechanical ventilation or continuous positive airway pressure and/or had neonatal seizures. Illness severity was quantified using the Score for Neonatal Acute Physiology. The retrospective cohort study included term infants who required mechanical ventilation and were born over a 5-year period (n = 347). Routine T4 screening was collected on the fifth day of life. TH was diagnosed in infants with a T4 <10%, with a TSH <25 μIU/mL. Clinical outcomes in infants with TH were compared with infants without TH.

Results. In the prospective study, infants in the sick group had lower T4 on the fifth day of life as compared with infants in the well group (11.7 ± 4.9 vs 18.9 ± 5.4 μg/dL), and 34% of infants in the sick group had a T4 <10th percentile compared with 6% of infants in the well group. T4 on day of life 5 was inversely correlated with Score for Neonatal Acute Physiology (R = −0.52). In the retrospective study, 21% of mechanically ventilated infants developed TH and were given statistically more inhaled nitric oxide, high-frequency ventilation, vasopressors, and pharmacologic paralysis when compared with infants without TH. Moreover, infants with TH were statistically more likely to die or require transfer to an extracorporeal membrane oxygenation center compared with infants without TH.

Conclusion. Our data show that, similar to preterm infants, ill term infants develop TH. Term infants with TH required more intensive rescue interventions, including inhaled nitric oxide and transfer to an extracorporeal membrane oxygenation center. However, whether T4 levels are a marker or a mediator of clinical outcome remains to be determined.
Health-Related Quality of Life in Young Survivors of Childhood Cancer Using the Minneapolis-Manchester Quality of Life-Youth Form
Authors: Shankar Sadhna , Robison Leslie , Jenney Meriel E.M. , Rockwood Todd H. , Wu Eric , Feusner James , Friedman Debra , Kane Robert L. , Bhatia Smita
Published: February 2005

Objective. To assess the health-related quality of life (HRQL) of 8- to 12-year-old children undergoing therapy for cancer or childhood-cancer survivors by using the Minneapolis-Manchester Quality of Life-Youth Form (MMQL-YF), a comprehensive, multidimensional self-report instrument with demonstrable reliability and validity.

Design, Setting, and Patients. The MMQL-YF consists of 32 items comprising 4 scales: physical functioning, psychologic functioning, physical symptoms, and outlook on life. Scoring on the MMQL ranges from 1 to 5; 5 indicates maximal HRQL. An overall quality-of-life (QOL) score is also computed. By using a cross-sectional study design, the MMQL-YF was administered to 90 off-therapy cancer survivors, 72 children with cancer undergoing active therapy, and 481 healthy children without a history of cancer or other chronic disease.

Results. Compared with healthy controls, children actively undergoing cancer treatment report low overall QOL, physical functioning, and outlook-on-life scores. However, off-therapy survivors report a superior overall QOL, compared with age-matched healthy controls.

Conclusions. Young survivors of childhood cancer report a favorable HRQL relative to healthy controls. These results are reassuring, suggesting that this group of survivors may have been too young to encounter some of the negative psychosocial impacts of cancer and its treatment.
Impact of a Diabetes Prevention Program on Body Size, Physical Activity, and Diet Among Kanien'kehá:ka (Mohawk) Children 6 to 11 Years Old: 8-Year Results From the Kahnawake Schools Diabetes Prevention Project
Authors: Paradis Gilles , Lévesque Lucie , Macaulay Ann C. , Cargo Margaret , McComber Alex , Kirby Rhonda , Receveur Olivier , Kishchuk Natalie , Potvin Louise
Published: February 2005

Objectives. Report the 8-year impact on body size, physical activity, and diet of a community-based diabetes prevention program for elementary-school children in a Kanien'kehá:ka (Mohawk) community in Canada.

Methods. Follow-up (1994–1996) of subjects in the intervention and comparison community and repeat cross-sectional measurements in the intervention community alone from 1994 to 2002. Measures included triceps and subscapular skinfold thicknesses, body mass index (BMI), weekly number of 15-minute episodes of physical activity, run/walk test times, television watching, and consumption of sugared foods, fatty foods, and fruits and vegetables.

Results. The longitudinal data of 1994–1996 showed some early positive effects of the program on skinfold thickness but not on BMI, physical activity, fitness, or diet. Repeat cross-sectional measures from 1994 to 2002 showed increases in skinfold thickness and BMI. Physical activity, fitness, and television watching showed favorable trends from 1994 to 1999 that were not sustained in 2002. Key high-fat and high-sugar foods consumption decreased, as did consumption of fruits and vegetables.

Conclusions. Although early results showed some successes in reducing risk factors for type 2 diabetes, these benefits were not maintained over 8 years.
Sleep-Wake Cycling on Amplitude-Integrated Electroencephalography in Term Newborns With Hypoxic-Ischemic Encephalopathy
Authors: Osredkar Damjan , Toet Mona C. , van Rooij Linda G. M. , van Huffelen Alexander C. , Groenendaal Floris , de Vries Linda S.
Published: February 2005

Objective. The objective of this amplitude-integrated electroencephalography (aEEG) study was to evaluate the influence of perinatal hypoxia-ischemia on sleep-wake cycling (SWC) in term newborns and assess whether characteristics of SWC are of predictive value for neurodevelopmental outcome.

Methods. From a consecutive series of newborns born during a 10-year period, the aEEG tracings of 171 term newborns with hypoxic-ischemic encephalopathy were assessed for the presence, time of onset, and quality of SWC. SWC patterns were categorized with regard to the background pattern on which they presented, as normal or abnormal SWC.

Results. SWC was seen in 95.4% of the surviving newborns and in 8.1% of those who died. The median time intervals from birth to onset of SWC were significantly different in newborns with hypoxic-ischemic encephalopathy grades I, II, and III (7, 33, and 62 hours, respectively). Newborns with seizure discharges developed SWC with a delay of 30.5 hours. Good outcome was associated with earlier onset of SWC and normal SWC pattern. The difference in the median Griffiths' developmental quotients in newborns who started SWC before/after 36 hours was 8.5 points. The good/poor neurodevelopmental outcome was predicted correctly by the onset of SWC before/after 36 hours in 82% of newborns.

Conclusions. The presence, time of onset, and quality of SWC reflected the severity of the hypoxic-ischemic insult to which newborns were exposed. The time of onset of SWC has a predictive value for neurodevelopmental outcome.
Racial and Ethnic Disparities in Early Childhood Health and Health Care
Authors: Flores Glenn , Olson Lynn , Tomany-Korman Sandra C.
Published: February 2005

Background. Racial/ethnic disparities in health care have received much national attention recently, but few studies have focused on disparities among children. We studied disparities in early childhood health and health care.

Methods. We analyzed data for 2608 children, 4 to 35 months of age, from the 2000 National Survey of Early Childhood Health, a nationwide household survey. The overall response rate was 65.6%. Survey questions addressed health, health care, and interactions with health care providers.

Results. Hispanic and black children were significantly less likely than whites to be in excellent/very good health (72%, 79%, and 90%, respectively) and were more likely to be uninsured (31%, 18%, and 9%, respectively). Only 60% of Hispanic and 77% of black parents would recommend their child's provider to others, compared with 84% of white parents. Minority parents more often reported that providers never or only sometimes understood their child-rearing preferences, and Hispanic parents most often reported that providers never or only sometimes understood their child's needs. Minority parents more often were asked about violence, smoking, drinking, and drug use. Hispanic and black parents averaged significantly fewer telephone calls to doctors' offices than did whites (2.0, 3.1, and 4.3 calls, respectively). Providers significantly less often referred Hispanic and black children to specialists (11% and 17%, respectively, compared with 22% for whites). Most disparities persisted in multivariate analyses, and several disparities were found between children with parents who completed surveys in Spanish and those with parents who completed surveys in English.

Conclusion. Young minority children experience multiple disparities in health status, insurance coverage, topics discussed during pediatric visits, parents feeling understood by providers, parental satisfaction, and referrals to specialists.
Anemia Is a Poor Predictor of Iron Deficiency Among Toddlers in the United States: For Heme the Bell Tolls
Authors: White Keith C.
Published: February 2005

Context. Many toddlers in the United States have their hemoglobin (Hb) measured periodically. Is this worthwhile?

Objective. To determine if the presence of anemia correctly diagnoses iron deficiency (ID) and if the absence of anemia correctly rules out ID in young children.

Methodology. An analysis of data from the US National Health and Nutrition Examination Survey III (1988–1994) was performed. Subjects were children 12 to 35 months old for whom complete blood counts and cardinal measures of iron nutrition (ferritin, transferrin saturation, and free erythrocyte protoporphyrin) were reported.

Results. In the US National Health and Nutrition Examination Survey III, the prevalence of ID ranged from 6% to 18% in various subpopulations of toddlers. In the general population, the positive predictive value of Hb concentration ([Hb]) <110 g/L for ID was 29% (95% confidence interval [CI]: 20–38%), and the sensitivity was 30% (95% CI: 20–40%). Changing the diagnostic cutoff point to [Hb] <107 g/L resulted in a positive predictive value of 38% (95% CI: 24–52%) but lowered the sensitivity to 15% (95% CI: 7–22%).

Conclusions. ID remains common in the United States. In agreement with other reports, anemia in toddlers in developed countries is more likely to be due to causes other than ID. Conversely, most children with ID are not anemic. Many false-positive and false-negative results render the measurement of Hb a screening test of relatively little value. The current detection strategy needlessly treats and retests many children without ID and leaves many iron-deficient toddlers unattended.
Adverse Events After Inactivated Influenza Vaccination Among Children Less Than 2 Years of Age: Analysis of Reports From the Vaccine Adverse Event Reporting System, 1990–2003
Authors: McMahon Ann W. , Iskander John , Haber Penina , Chang Soju , Woo E. Jane , Braun M. Miles , Ball Robert
Published: February 2005

Background. In April 2002, the Advisory Committee on Immunization Practices (ACIP) encouraged providers to vaccinate healthy 6- to 23-month-old infants and children with trivalent influenza vaccine (TIV).

Objectives. To describe adverse events (AEs) reported to the Vaccine Adverse Event Reporting System (VAERS) after TIV vaccination among children <2 years of age and to compare reports before the ACIP guideline (January 1990 to June 2002) and after the ACIP guideline (July 2002 to June 2003).

Methods. VAERS is a passive vaccine safety surveillance system begun by the Food and Drug Administration and the Centers for Disease Control and Prevention in 1990. We reviewed reports to VAERS for children <2 years of age who received TIV, alone or in combination with other vaccines. Influenza seasons were defined as the period from July 1 of one year to June 30 of the following year.

Results. Between 1990 and 2003, VAERS received 166 TIV reports for children <2 years of age. There were 62 reports (37%) after administration of TIV alone and 104 reports (63%) after administration of TIV and ≥1 other vaccine. Approximately one third of reports (N = 61) were in the post-ACIP guideline period. The 4 most frequent AE coding terms were fever (N = 59, 35%), unspecified or urticarial rash (42, 25%), seizure (28, 17%), and injection site reaction (28, 17%). The median number of days from vaccination to symptom onset, the percentage of reports that represented serious AEs, and the gender distribution were similar in the pre-ACIP guideline and post-ACIP guideline periods. The percentage of reports describing an underlying medical condition for the subject decreased from 58% before the ACIP guideline to 37% after the ACIP guideline. Nineteen of 28 seizure reports (68%) described fever with the seizure within 2 days after vaccination. Seizure was the most frequent coding term (N = 10, 7 with fever) among 23 serious reports. The annual number of TIV-related VAERS reports for children <2 years of age increased in the post-ACIP guideline period, probably at least in part because of an increase in the number of vaccinees after the ACIP announcement. The safety profiles in the pre-ACIP guideline and post-ACIP guideline periods were similar.

Conclusions. In October 2003, the ACIP recommended that all healthy children 6 to 23 months of age be vaccinated with TIV, starting in the 2004–2005 influenza season. This study provides generally reassuring, although limited, data regarding the safety of TIV among children in this age range. Continued surveillance for seizures and other clinically significant AEs is warranted and will continue.
The Assessment of Attention-Deficit/Hyperactivity Disorder in Rural Primary Care: The Portability of the American Academy of Pediatrics Guidelines to the “Real World”
Authors: Polaha Jodi , Cooper Stephanie L. , Meadows Tawnya , Kratochvil Christopher J.
Published: February 2005

Objective. To examine the implementation of a protocol for the assessment of attention-deficit/hyperactivity disorder (ADHD) in rural pediatric practices. The protocol was designed to provide an efficient means for pediatricians to learn and use the ADHD guidelines put forth by the American Academy of Pediatrics (AAP).

Methods. Primary care staff (physicians, nurses, etc) from 2 rural pediatric practices were trained to use the ADHD-assessment protocol. Medical records for 101 patients were reviewed from 1 to 2 years before the introduction of the protocol and for 86 patients during the subsequent 2 to 3 years to assess compliance with the AAP guidelines. In addition, 34% of the scales scored by the staff were rescored to check for scoring accuracy.

Results. Before the availability of the AAP guidelines and the implementation of the assessment protocol, neither primary care site was consistently collecting the comprehensive information that is now recommended for an ADHD assessment. Parent and/or teacher rating scales were collected for only 0% to 21% of assessments across sites. When provided with brief training and supporting materials, medical records reflected significant improvement in the ascertainment of clinically necessary ADHD information, with parent and teacher rating scales present 88% to 100% of the time. Staff demonstrated an ability to score rating scales with a high degree of accuracy. The integrity of protocol collection and management was maintained 2 to 3 years after training.

Conclusions. An efficient system for conducting ADHD assessments according to AAP guidelines in rural pediatrics clinics can be initiated and maintained with integrity. Additional research is needed to determine if this system improves diagnostic decision-making and patient outcomes.
Gender Differences in Perinatal HIV Acquisition Among African Infants
Authors: Taha Taha E. , Nour Samah , Kumwenda Newton I. , Broadhead Robin L. , Fiscus Susan A. , Kafulafula George , Nkhoma Chiwawa , Chen Shu , Hoover Donald R.
Published: February 2005

Objective. We investigated gender-specific risks of mother-to-child transmission (MTCT) at birth and at 6 to 8 weeks among infants born to HIV-infected African women.

Design. Follow-up study of infants enrolled in 2 randomized, phase III, clinical trials to prevent MTCT, conducted in Blantyre, Malawi, in southeast Africa.

Methods. Infants were enrolled at birth and monitored postnatally, and their HIV status was assessed at birth and at 6 to 8 weeks (assessment beyond 6–8 weeks is ongoing). Statistical analyses were stratified according to gender, and comparisons were made with descriptive, univariate, and multivariate statistical tests. MTCT was estimated at birth and at 6 to 8 weeks among infants who were not infected at birth.

Results. Overall, 966 boys and 998 girls were enrolled. The rate of HIV transmission at birth was 9.5% (187 of 1964 infants). However, at birth significantly more girls (12.6%) than boys (6.3%) were infected with HIV. This association remained significant after controlling for maternal viral load and other factors. Among infants who were uninfected at birth, 8.7% (135 of 1554 infants) acquired HIV by 6 to 8 weeks; of these infants, more girls acquired HIV (10.0%), compared with boys (7.4%).

Conclusions. Female infants may be more susceptible to HIV infection before birth and continuing after birth. Alternatively, in utero mortality rates of HIV-infected male infants may be disproportionately higher and thus more HIV-infected female infants are born. In areas of sub-Saharan Africa, where HIV infection rates are high among women of reproductive age, the magnitude of the gender transmission differences observed in this study could have clinical, preventive, and demographic implications.
Helping Families Raise Children With Special Health Care Needs at Home
Authors: Johnson Chris Plauché , Kastner Theodore A. ,   and the Committee/Section on Children With Disabilities
Published: February 2005

This Clinical Report was retired June 2009.

One goal of Healthy People 2010 is to reduce the number of people with disabilities in congregate care facilities, consistent with permanency-planning principles, to 0 by 2010 for persons aged 21 years and under (objective 6–7). Congregate care, in this regard, is defined as any setting in which 4 or more persons with disabilities reside, regardless of whether the residence is located in the community, such as a school, group home, nursing facility, or institution. Although this particular public health objective may reflect an unfamiliar concept for some pediatricians, the American Academy of Pediatrics supports the goals and objectives of Healthy People 2010 as well as the medical home and the provision of community-based, culturally effective, coordinated, and comprehensive care for children with special health care needs and their families. To advise families caring for children with special health care needs effectively, the pediatrician should be familiar with the principles of permanency planning and well informed of local family-support services. The pediatrician should also work with the family to identify the range of long-term supports and services available for their child. These supports may include respite for biological families as well as various additional parenting models such as shared parenting, foster care, alternate parents, and adoption. Although family-based supports are preferable, families may consider other out-of-home placements including group homes, placement in a nursing facility, or other forms of institutional care when sufficient family-based services are not available. Once all the options are understood, issues regarding quality of care can be individualized and judged by the parent or guardian, in close collaboration with the pediatrician and other professionals with expertise in permanency planning and long-term supports and services.

The purpose of this clinical report is to educate physicians on the philosophy of providing a permanent family environment (permanency planning) for all children, including those with special health care needs, and the importance of adequate and accessible community services to support and maintain the well-being of all family members.
Die Jagd auf Moleküle, die nie existiert haben: Falsch zugeordnete Naturstoffstrukturen und die Rolle der chemischen Synthese in der modernen Strukturaufklärung
Authors: Nicolaou K. C. , Snyder Scott A.
Published: February 2005

Im Laufe der vergangenen 50 Jahre hat hinsichtlich der Aufklärung der Strukturen unbekannter Naturstoffe eine gewaltige Umwälzung stattgefunden. In der ersten Hälfte des vergangenen Jahrhunderts war man fast ausschließlich auf die Kunst der chemischen Synthese angewiesen, um in jahrelanger Arbeit – hauptsächlich mithilfe von Abbaureaktionen und Derivatisierungen – Hypothesen zur Struktur zu überprüfen. Heute stehen mit der multidimensionalen NMR‐Spektroskopie, der hochauflösenden Massenspektrometrie und nicht zuletzt mit der Röntgenstrukturananlyse leistungsstarke Verfahren zur Verfügung, um hoch komplexen Naturstoffen schnell Strukturen zuzuordnen – selbst dann, wenn weniger als ein Milligramm Substanz isoliert wurde. Man könnte daher behaupten, die Charakterisierung von Naturstoffen sei zu einer Routineaufgabe geworden, für deren Lösung nicht einmal mehr ein Reaktionsgefäß benötigt wird – doch ist das wirklich so? Dieser Aufsatz zeigt, dass phantasievolle Detektivarbeit und chemische Synthesen bei der Lösung der faszinierendsten molekularen Rätsel der Natur nach wie vor eine wichtige Rolle spielen.
A Novel Series of Vanadium‐Sulfite Polyoxometalates: Synthesis, Structural, and Physical Studies
Authors: Miras Haralampos N. , Raptis Raphael G. , Lalioti Nikolia , Sigalas Michael P. , Baran Peter , Kabanos Themistoklis A.
Published: February 2005

Reaction of NH4VO3 with sulfur dioxide affords the hexanuclear cluster (NH4)2(Et4N)[(VIVO)6(μ4‐O)2(μ3‐OH)2(μ3‐SO3)4(H2O)2]Cl⋅H2O (1), and the decapentanuclear host–guest compound (Et4N)5{Cl⊂ [(VO)15(μ3‐O)18(μ‐O)3]}⋅3 H2O (2). Sequential addition of magnesium oxide to an acidic aqueous solution of NH4VO3 (pH≈0) followed by (NH4)2SO3 resulted in the formation of either the non‐oxo polymeric vanadium(IV) compound trans‐(NH4)2[VIV(OH)2(μ‐SO3)2] (3) or the polymeric oxovanadium(IV) sulfite (NH4)[VIVO(SO3)1.5(H2O)]⋅2.5 H2O (4) at pH values of 6 and 4, respectively. The decameric vanadium(V) compound {Na4(μ‐H2O)8(H2O)6}[Mg(H2O)6][V${{{{\rm V}\hfill \atop 10\hfill}}}$(O)8(μ6‐O)2(μ3‐O)14]⋅3 H2O (5) was synthesised by treating an acidic aqueous solution of NH4VO3 with MgO and addition of NaOH to pH≈6. All the compounds were characterised by single‐crystal X‐ray structure analysis. The crystal structure of compound 1 revealed an unprecedented structural motif of a cubane unit [M4(μ4‐O)2(μ3‐OH)2] connected to two other metal atoms. Compound 3 comprises a rare example of a non‐oxo vanadium(IV) species isolated from aqueous solution and in the presence of the reducing agent SO32−, while compound 4 represents a rare example of an open‐framework species isolated at room temperature (20 °C). In addition to the synthesis and crystallographic studies, we report the IR and magnetic properties (for 1, 2 and 3) of these vanadium clusters as well as theoretical studies on compound 3.
Synthetic Fragments of Antigenic Lipophosphoglycans from Leishmania major and Leishmania mexicana and Their Use for Characterisation of the Leishmania Elongating α‐D‐Mannopyranosylphosphate Transferase
Authors: Higson Adrian P. , Ross Andrew J. , Tsvetkov Yury E. , Routier Françoise H. , Sizova Olga V. , Ferguson Michael A. J. , Nikolaev Andrei V.
Published: February 2005

The phosphorylated branched heptasaccharides 7 and 8, the octasaccharide 9 and the phosphorylated trisaccharides 5 and 6, which are fragments of the phosphoglycan portion of the surface lipophosphoglycans from Leishmania mexicana (5) or L. major (6–9), were synthesised by using the glycosyl hydrogenphosphonate method for the preparation of phosphodiester bridges. The compounds were tested as acceptor substrates/putative inhibitors for the Leishmania elongating α‐D‐mannosylphosphate transferase.
Removal of Fluorine from and Introduction of Fluorine into Polyhalopyridines: An Exercise in Nucleophilic Hetarenic Substitution
Authors: Bobbio Carla , Rausis Thierry , Schlosser Manfred
Published: February 2005

Starting from six industrially available fluorinated pyridines, an expedient access to all three tetrafluoropyridines (2–4), all six trifluoropyridines (5–10), and the five non‐commercial difluoropyridines (11–14 and 16) was developed. The methods employed for the selective removal of fluorine from polyfluoropyridines were the reduction by metals or complex hydrides and the site‐selective replacement by hydrazine followed by dehydrogenation–dediazotation or dehydrochlorination–dediazotation. To introduce an extra fluorine atom, a suitable precursor was metalated and chlorinated before being subjected to a chlorine/fluorine displacement process.
Testing the robustness of CIECAM02
Authors: Li C. J. , Luo M. R.
Published: January 2005

CIE TC8‐01 has adopted a new color appearance model: CIECAM021 replaces the CIECAM97s.2 The new model consists of a number of refinements and simplifications of the CIECAM97s color appearance model. This article describes further tests to the robustness of the forward and reverse modes. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 99–106, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20087
Role of p53 status in chemosensitivity determination of cancer cells against histone deacetylase inhibitor sodium butyrate
Authors: Joseph Jeena , Wajapeyee Narendra , Somasundaram Kumaravel
Published: February 2005

Histone deacetylases inhibitors (HDIs) induce growth arrest and apoptosis in a variety of human cancer cells. Sodium butyrate (NaB), a histone deacetylase inhibitor, has been shown to cause a G1 cell cycle arrest by inducing p21WAF1/CIP1 in a p53‐independent manner. In this report, we present evidence for activation of p53 pathway by NaB and its role in the NaB‐mediated growth suppression. Addition of NaB increased the levels of p53 involving a p14ARF‐dependent post‐transcriptional mechanism. NaB induced p53 is functional as it activated p53‐specific reporter, induced the level of p21WAF1/CIP1, inhibited cellular DNA synthesis and induced apoptosis. By using HPV 16 E6 stable transfectants as well as p53 null cancer cells, we show that NaB suppresses the growth of WT p53 containing cells more efficiently. NaB inhibited DNA synthesis to similar extent both in the presence and absence of p53. However, NaB treatment lead to a major G2/M arrest of cells in the presence of p53, while cells without wild‐type p53 accumulated mainly in G1 phase of the cell cycle. Furthermore, apoptosis induction by NaB is greatly reduced in the absence of p53. These results suggest that p53 pathway mediates in part growth suppression by NaB and the p53 status may be an important determinant of chemosensitivity in HDI based cancer chemotherapy. © 2005 Wiley‐Liss, Inc.
Myxoid liposarcoma FUS‐DDIT3 fusion oncogene induces C/EBP β‐mediated interleukin 6 expression
Authors: Göransson Melker , Elias Erik , Ståhlberg Anders , Olofsson Anita , Andersson Carola , Åman Pierre
Published: February 2005

The myxoid/round cell liposarcoma oncogene FUS‐DDIT3 is the result of a translocation derived gene fusion between the splicing factor FUS and DDIT3. In order to investigate the downstream targets of DDIT3, and the transforming effects of the FUS‐DDIT3 fusion protein, we have introduced DDIT3‐GFP and FUS‐DDIT3‐GFP constructs into a human fibrosarcoma cell line. The gene expression profiles of stable transfectants were compared to the original fibrosarcoma cell line by microarray analysis. We here report that the NFκB and C/EBP β controlled gene IL6 is upregulated in DDIT3‐ and FUS‐DDIT3‐expressing fibrosarcoma cell lines and in myxoid liposarcoma cell lines. Strong expression of the tumor associated multifunctional cytokine interleukin 6 was confirmed both at mRNA and protein level. Knockdown experiments using siRNA against CEBPB transcripts showed that the effect of FUS‐DDIT3 on IL6 expression is C/EBP β dependent. Chromatin immunoprecipitation revealed direct interaction between the IL6 promoter and the C/EBP β protein. In addition, the effect of DDIT3 and FUS‐DDIT3 on the expression of other acute phase genes was examined using real‐time PCR. We demonstrate for the first time that DDIT3 and FUS‐DDIT3 show opposite transcriptional regulation of IL8 and suggest that FUS‐DDIT3 may affect the synergistic activation of promoters regulated by C/EBP βκB. © 2005 Wiley‐Liss, Inc.
Epidemiologic and viral factors associated with cervical neoplasia in HPV‐16‐positive women
Authors: Rajeevan Mangalathu S. , Swan David C. , Nisenbaum Rosane , Lee Daisy R. , Vernon Suzanne D. , Ruffin Mack T. , Horowitz Ira R. , Flowers Lisa C. , Kmak David , Tadros Talaat , Birdsong George , Husain Mujtaba , Srivastava Sudhir , Unger Elizabeth R.
Published: February 2005

While infection with high‐risk HPV is the most important risk factor for cervical cancer, HPV alone is insufficient. Our purpose was to identify viral and epidemiologic factors associated with cervical disease in HPV‐16 DNA‐positive women referred to colposcopy. We used a standardized interview to collect epidemiologic data from consenting women. Total nucleic acids from exfoliated cervical cells were used for all viral assays (HPV detection and typing using L1 consensus PCR with line probe hybridization, variant classification by sequencing, viral load and transcript copy determination by quantitative PCR and transcript pattern by nested RT‐PCR). Cervical disease was based on colposcopic biopsy. Logistic regression was used to calculate ORs with 95% CIs. There were 115 HPV‐16 positive women among 839 enrollees. By univariate analyses, age >25 years (OR = 3.05, 95% CI 1.20–7.76), smoking (OR = 3.0, 95% CI 1.19–7.56), high viral load (OR = 5.27, 95% CI 2.05–13.60), detection of both E6 and E6*I transcripts (OR = 10.0, 95% CI 2.1–47.58) and high transcript copies (OR = 5.56, 95% CI 2.05–13.60) were significant risk factors for CIN III with reference to No CIN/CIN I. Less than a third of the women (31.5%) had prototype HPV‐16 detected, and variants showed no association with disease, viral load or transcription. Viral DNA and transcript copies were highly correlated, and the ratio of transcript copies to DNA copies was not changed with disease status. While viral load, transcript copies and transcript pattern were statistically associated with CIN III, none of these measures effectively discriminated between HPV‐16 women with disease requiring treatment and those who could be followed. Cellular proliferation and differentiation pathways affected by HPV should be investigated as biomarkers for cervical cancer screening. © 2005 Wiley‐Liss, Inc.
Determination of arginine in dietary supplements
Authors: Gange Michelle E , Francis Paul S , Costin Jason W , Barnett Neil W , Lewis Simon W
Published: February 2005

We present a rapid and sensitive flow injection method for the determination of arginine in dietary supplements. Detection was based on the chemiluminescence reaction of arginine with alkaline hypobromite. The response is proportional to analyte concentration over the calibration range, from 2.5 × 10−6 to 1 × 10−4 M, and a relative standard deviation of 1% was calculated (1 × 10−5 M, n = 12). Samples required only aqueous dilution prior to analysis, and over 100 samples could be analysed per hour, which is superior to that achieved with conventional colorimetric and enzymatic procedures. The results obtained with the flow injection methodology were concordant with those achieved using high‐performance liquid chromatography employing pre‐column derivatisation and fluorescence detection. Copyright © 2005 Society of Chemical Industry
Ethephon‐induced fractional changes of pectic polysaccharides in developing cape gooseberry (Physalis peruviana L) fruits
Authors: Majumder Kausik , Mazumdar Bibhas C
Published: February 2005

Pectic polysaccharides extracted from fruit tissue of cape gooseberry (Physalis peruviana L) at different maturity levels were fractionated and analyzed for galacturonic acid backbone molecules. Preharvest spray of the fruits at 7 days old with ethephon resulted in a higher accumulation of water‐soluble and oxalate‐soluble pectic fractions than non‐treated fruits, while this treatment effectively enhanced the polygalacturonase enzyme activity necessary for maintenance of pectin degradation. Treatment with ethephon not only enhanced the solubilization rate but also resulted in a net increase in total pectic polymer content in developing cape gooseberry fruits. Copyright © 2005 Society of Chemical Industry
In vitro procedure to predict apparent antioxidant release from wholegrain foods measured using three different analytical methods
Authors: Nagah Abdulbaset M , Seal Chris J
Published: February 2005

Several methods have been applied to the measurement of antioxidants in biological samples. Extraction methods have previously relied on chemical methods which are non‐physiological. This paper reports the use of an in vitro method with enzymatic and fermentation steps, designed to mimic digestion through the gastrointestinal tract, on release of antioxidants from a range of wholegrain foods. A total of 41 samples, (31 raw foods, 10 of which were also analysed after cooking) were analysed using the ferric reducing antioxidant capacity and Trolox equivalent antioxidant capacity methods. Six samples were also measured using the oxygen radical absorption capacity method. The three antioxidant assay methods gave different apparent antioxidant activity trends, and the range of values was dependent on the type of food. The effects of cooking were mainly observed in the early stages of the incubation procedure, suggesting that cooking may destroy soluble antioxidants but not those bound within the food matrix. For all samples, apparent antioxidant release increased during the incubation period, suggesting that antioxidants bound within the food matrix may be released and exert their effects in different regions of the gastrointestinal tract. Copyright © 2005 Society of Chemical Industry
An NMR investigation of the importance of intramolecular hydrogen bonding in determining the conformational equilibrium of ethylene glycol in solution
Authors: Petterson Krag A. , Stein Robin S. , Drake Michael D. , Roberts John D.
Published: February 2005

Although conformational analysis by NMR of ethylene glycol indicates generally strong preferences for the gauche conformation in solvents ranging from water to chloroform, the bulk of the NMR evidence indicates that intramolecular hydrogen bonding between the hydroxyl groups is unlikely to be a significant factor in determining that preference, except possibly in fairly non‐polar solvents. The ‘gauche effect’ is clearly very important, especially in aqueous solution. Copyright © 2005 John Wiley & Sons, Ltd.
Amino acid coupling patterns in thermophilic proteins
Authors: Liang Han‐Kuen , Huang Chia‐Mao , Ko Ming‐Tat , Hwang Jenn‐Kang
Published: February 2005

Structural analysis is useful in elucidating structural features responsible for enhanced thermal stability of proteins. However, due to the rapid increase of sequenced genomic data, there are far more protein sequences than the corresponding three‐dimensional (3D) structures. The usual sequence‐based amino acid composition analysis provides useful but simplified clues about the amino acid types related to thermal stability of proteins. In this work, we developed a statistical approach to identify the significant amino acid coupling sequence patterns in thermophilic proteins. The amino acid coupling sequence pattern is defined as any 2 types of amino acids separated by 1 or more amino acids. Using this approach, we construct the ρ profiles for the coupling patterns. The ρ value gives a measure of the relative occurrence of a coupling pattern in thermophiles compared with mesophiles. We found that thermophiles and mesophiles exhibit significant bias in their amino acid coupling patterns. We showed that such bias is mainly due to temperature adaptation instead of species or GC content variations. Though no single outstanding coupling pattern can adequately account for protein thermostability, we can use a group of amino acid coupling patterns having strong statistical significance (p values < 10−7) to distinguish between thermophilic and mesophilic proteins. We found a good correlation between the optimal growth temperatures of the genomes and the occurrences of the coupling patterns (the correlation coefficient is 0.89). Furthermore, we can separate the thermophilic proteins from their mesophilic orthologs using the amino acid coupling patterns. These results may be useful in the study of the enhanced stability of proteins from thermophiles—especially when structural information is scarce. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Coherent control of the biexciton in a single quantum dot
Authors: Flissikowski T. , Betke A. , Akimov I. A. , Henneberger F.
Published: February 2005

We report on coherent control of the two‐photon transition between the ground state and the biexciton state on a single quantum dot level. The population of the biexciton is monitored by the cascaded spontaneous emission of the biexciton complex via the exciton states. The signal shows interference pattern at the double laser frequency and its contrast decays non‐exponentially at the time scale of 10 ps. The contrast decrease is attributed to a dynamical inhomogeneous broadening of the energy levels due to long‐term fluctuations in the dot environment. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantum dot VCSELs
Authors: Ustinov Victor M. , Maleev Nikolai A. , Kovsh Alexey R. , Zhukov Alexey E.
Published: February 2005

Molecular beam epitaxy growth of InAs/InGaAs QD structures on GaAs substrates as well as fabrication and performance of long‐wavelength QD edge‐emitting lasers and VCSELs are discussed. 1.3 µm QD VCSELs were successfully fabricated from the structures with several QD planes inserted into the optical microcavity with AlO–GaAs and AlGaAs–GaAs Bragg reflectors. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Energy partitioning in association processes
Authors: Carvalho Alexandre R. F. , Melo André
Published: February 2005

In this work, the partition method introduced by Melo and Ramos has been extended to enable the decomposition of the stabilization energies associated with molecular association processes into physical meaningful components (conformational rearrangement, nonbonding, bonding, and polarization plus charge transfer). This partition scheme, within a semiempirical formalism, enables a complete separability of the above‐mentioned components. The molecular system has also been partitioned into perturbed and bulk regions, defined as flexible variable‐size entities. This procedure enables one to evaluate the range of the perturbation originated by an association process. Several association processes (covalent and noncovalent) have been studied using this methodology. The results obtained enable us to conclude that the current decomposition scheme can be used for understanding the cohesive phenomena. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Reporting small Δ17O values: existing definitions and concepts
Authors: Assonov S. S. , Brenninkmeijer C. A. M.
Published: February 2005

The three‐isotope tracer Δ17O is increasingly used in atmospheric chemistry and other research areas. Thanks to the development of isotope‐ratio mass spectrometry (IRMS), δ17O and δ18O can be determined with a precision of a few 0.01‰, and values for Δ17O may be calculated with similar precision. However, interpreting small and precisely determined Δ17O values as a deviation from an expected mass‐dependent fractionation process is not straightforward. Several aspects are of high importance. In the present paper we review existing definitions, formulas and some other aspects of Δ17O reporting. One of the most confusing aspects is a variance of definitions and corresponding formulas. While Δ17O is traditionally defined to characterise a data point, i.e. Δ17O is considered as a deviation from an expected mass‐fractionation line, the recently introduced definition (Miller MF. Geochim. Cosmochim. Acta 2002; 66: 188) characterises a fractionation line itself, in terms of its ordinate intercept. The formulas corresponding to this definition gives a characteristic for a specific process. When the ‘traditionally defined’ Δ17O is in use, an expected fractionation processes—the key point for Δ17O reporting—should be defined and parameterised with the same accuracy as intended for reporting Δ17O. When Δ17O is reported for a data point, not only a value for λ but an ordinate intercept of a reference fractionation line should be given with high accuracy. We note that defining a single fractionation process is hardly possible for many natural compounds. For such compounds we propose to use a phenomenological reference line, namely an isotope composition range of natural sources. Next, aspects of Δ17O comparison and mass‐balance calculations are considered. All the aspects considered for Δ17O may be relevant for others three‐isotope tracers, e.g. Δ33S. Copyright © 2005 John Wiley & Sons, Ltd.
Investigation on the performance of space‐time block coded ultrawide band communication systems
Authors: Du Yinggang , Tai Chan Kam
Published: February 2005

Ultrawide band (UWB) communication systems show many advantages over the conventional narrow band systems. In this paper, three UWB systems at the same transmission efficiency are investigated. The first one is a conventional system with only one transmit antenna (non‐STBC). The second one is combined with the space‐time block coding (STBC) over one symbol (STBC‐1). The third system is combined with the STBC over two symbols (STBC‐2), which is in accordance with Almouti's scheme. Both theoretical analysis and simulations show that the STBC‐1 system performs the best. In addition, the adoption of the normalized modified Hermite polynomial based orthogonal pulses (NMHP) instead of the Gaussian pulse (GP) to represent theM‐ary symbol constellation can increase the data rate and lead to an improvement of the signal to noise ratio (SNR) by about 10log10MdB at the bit error rate (BER) of 10−4at any symbol constellation for any UWB system. The simulations in both flat‐fading channels and frequency‐selective channels have confirmed such improvement. Copyright © 2005 John Wiley & Sons, Ltd.
Offset‐stack scheme and receivers for CCC‐based multicarrier CDMA architecture
Authors: Huang Aiping , Li Jing , Liu Shao‐Bo
Published: February 2005

The main objective of this paper is to present new receiver structures to improve the applicability of a recently developed multicarrier CDMA architecture based on complete complementary codes. A mathematical description of the new system is presented in this paper. It is found that though it is the offset‐stack scheme that guarantees high spectral efficiency and scalable rate‐matching, error propagation under multipath fading noisy channel conditions is generated due to such special spreading modulation scheme and the corresponding recursive receiver. In order to avoid error propagation, the precondition of multipath replica separation is derived mathematically so that a non‐recursive receiver can be employed. The range of the channel delay spread is discussed and the impact of the time shift in offset‐stack spreading modulation on spectral efficiency is analyzed. Then, a RAKE receiver is proposed to further improve the performance through multipath diversity. Simulations are carried out under multipath fading noisy channel conditions to further verify the theoretical analysis. Performance loss caused by error propagation is observed by comparing the performances of the recursive receiver and the non‐recursive receiver. With the same spectral efficiency, the proposed offset‐stack scheme and the RAKE receiver gain obvious performance improvement compared to the existing offset‐stack scheme and the recursive receiver. Copyright © 2005 John Wiley & Sons, Ltd.