bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluorescence shell: A novel view of sclereid morphology with the Confocal Laser Scanning Microscope
Authors: Angeles Guillermo , Owens Shirley A. , Ewers Frank W. 
Published: May 2004

AbstractConfocal Laser Scanning Microscopy (CLSM) was used to observe sclereids from stems of Avicennia germinans and from fruits of two species of pear (Pyrus calleryana “Bradford” and P. communis “Red Bartlett”). The images obtained from thick (25 to 100 μm) free‐hand sections were, in certain respects, far superior to those obtained by other, more invasive and time‐consuming microscopic techniques upon which previous reports of sclereid morphology were based. The cell wall surfaces, including the “internal” surfaces of the branched pit canals and cell lumens, were much accentuated with the techniques we describe, resulting in a “fluorescence shell” image, meaning the cell wall did not stain all the way through but instead only at the inner and outer wall surfaces, including the edges of ramiform pits. By controlling the time of staining with 1% aqueous Safranin O, or by changing the number of optical sections used in extended focus images, it was possible to get either a conventional view of the cell wall structure or a unique, three‐dimensional view of the elaborate cell interconnections. Similar fluorescence shell images of sclereids were also obtained using a periodic‐Schiff (PAS) staining system, but the stain was not as specific to sclereid cell walls as was the Safranin O stain. Particularly with the use of a narrow range band pass emission filter of 505–530 nm, the Safranin O staining may be more specific to lignin than reported in the literature. Microsc. Res. Tech. 63:282–288, 2004. © 2004 Wiley‐Liss, Inc.
The risk of hyponatremia in older adults using desmopressin for nocturia: A systematic review and meta‐analysis
Authors: Weatherall Mark 
Published: May 2004

AbstractAimsTo estimate the incidence of hyponatremia in older adults who use nasal or oral desmopressin to treat nocturia.Materials and MethodsA systematic review and meta‐analysis of cohort studies and randomised controlled trials of the use of nasal or oral desmopressin for older adults with nocturia. The incidence of hyponatremia was estimated by a random effects model for binomial data.ResultsSeventy‐five papers were identified by the literature review of which 14 were reports of randomised trials or cohort studies. Seven studies reported the incidence of hyponatremia. The pooled estimate for the incidence of hyponatremia was 7.6% (95% CI 3.7–15.1).ConclusionsHyponatremia is a relatively common adverse effect of the use of desmopressin for the treatment of nocturia and caution and regular monitoring should be part of the use of this management option for nocturia in older adults. © 2004 Wiley‐Liss, Inc.
The reproducibility of urodynamic findings in healthy female volunteers: Results of repeated studies in the same setting and after short‐term follow‐up
Authors: Gupta Amit , Defreitas Gina , Lemack Gary E. 
Published: May 2004

AbstractAimTo assess the immediate (same testing period) and short‐term (within 6 months) repeatability of urodynamic (UD) testing in asymptomatic healthy female volunteers.Materials and MethodsTwenty asymptomatic women with a mean age of 41.8 years (30–55) agreed to undergo a UD assessment which consisted of noninvasive uroflowmetry, post‐void residual (PVR) measurement, medium‐fill cystometry, and pressure flow study with perineal surface electromyographic (EMG) electrodes. The UDS evaluation was repeated immediately without removing the catheters (a two‐fill and void study). Sixteen women returned for an identical UD assessment 1–5 months later. Immediate and short‐term repeatability of UD parameters was assessed by calculating the coefficient of repeatability (COR).ResultsThe repeatability of certain parameters of immediate UD testing could not be calculated since there was an apparent influence of the first test on the second (i.e., an apparent accommodation noted in bladder filling volumes). Other immediate UD values (maximum flow, detrusor pressure at maximum flow, voided volume) had high COR values, as did all UD values on short‐term testing, indicating relatively poor repeatability. Picking the ‘best’ pressure flow value (highest flow rate with accompanying detrusor pressure) did not consistently improve the COR values.ConclusionsThe lack of repeatability of UD studies likely stems from a combination of the true physiological fluctuations in bladder function and the inherent relative insensitivity of our instruments in conducting these testing. Knowledge of the limitations of current technology is essential in allowing us to better utilize these studies in evaluating our patients and further improving diagnostic strategies. © 2004 Wiley‐Liss, Inc.
ICIQ: A brief and robust measure for evaluating the symptoms and impact of urinary incontinence
Authors: Avery Kerry , Donovan Jenny , Peters Tim J. , Shaw Christine , Gotoh Momokazu , Abrams Paul 
Published: May 2004

AbstractAimsTo develop and evaluate the International Consultation on Incontinence Questionnaire (ICIQ), a new questionnaire to assess urinary incontinence and its impact on quality of life (QoL).MethodsA developmental version of the questionnaire was produced following systematic literature review and views of an expert committee and patients. Several studies were undertaken to evaluate the psychometric properties of the questionnaire, including content, construct and convergent validity, reliability and sensitivity to change.ResultsThe ICIQ was easily completed, with low levels of missing data (mean 1.6%). It was able to discriminate among different groups of individuals, indicating good construct validity. Convergent validity was acceptable, with most items demonstrating ‘moderate’ to ‘strong’ agreement with other questionnaires. Reliability was good, with ‘moderate’ to ‘very good’ stability in test‐retest analysis and a Cronbach's alpha of 0.95. Items identified statistically significant reductions in symptoms from baseline following surgical and conservative treatment. Item reduction techniques were used to determine the final version and scoring scheme, which also demonstrated good psychometric properties.ConclusionsThe final ICIQ comprises three scored items and an unscored self‐diagnostic item. It allows the assessment of the prevalence, frequency, and perceived cause of urinary incontinence, and its impact on everyday life. The ICIQ is a brief and robust questionnaire that will be of use in outcomes and epidemiological research as well as routine clinical practice. © 2004 Wiley‐Liss, Inc.
How reliable are bladder perceptions during cystometry?
Authors: Erdem Erim , Akbay Erdem , Doruk Erdal , Çayan Selahittin , Acar Deniz , Ulusoy Ercüment 
Published: May 2004

AbstractAimsSensory input is important for bladder control in daily life. It has been reported that perceptions during cystometry are subjective. To help refine this subjectivity, objective and semi‐objective tests (e.g., sensory thresholds of electrical stimulation) have been recommended by The International Continence Society. However, the reliability of such studies has not been established. This study was designed to evaluate the reliability of bladder perceptions during cystometry.MethodsThe study included 59 patients with urologic complaints. The average age of 40 male and 19 female patients was 58.1 years (range: 14–83). After insertion of an 8F double lumen catheter, patients were blinded to the pump and screen process. During Phase I nothing was infused. In Phase II, filling cystometry was performed with 50 ml/min pump speed and then the bladder was emptied. Phase III was performed with the same method used in Phase I. The time that each sensation was perceived, in seconds, was used to compare sensations. The bladder volume, at which sensations were perceived, was recorded at Phase II.ResultsExcept for strong desire, there were no statistically significant differences between the mean times in seconds elapsed till sensations in Phases I and III, but they were different from those in Phase II. The time elapsed until strong desire was not different in each of the three phases. However, there was strong a correlation in the ratios of sensations to strong desire between Phase I and II (r = 1, P = 0.01), Phase I and III (r = 0.99, P = 0.01), and Phase II and III (r = 0.98, P = 0.01).ConclusionsProprioception of the bladder filling during cystometry is subjective. This data shows that sensations noticed by the patient during filling cystometry may be related to stimuli other than bladder filling. © 2004 Wiley‐Liss, Inc.
A stochastic integer programming approach to solving a synchronous optical network ring design problem
Authors: Smith J. Cole , Schaefer Andrew J. , Yen Joyce W. 
Published: May 2004

AbstractWe develop stochastic integer programming techniques tailored toward solving a Synchronous Optical Network (SONET) ring design problem with uncertain demands. Our approach is based on an L‐shaped algorithm, whose (integer) master program prescribes a candidate network design, and whose (continuous) subproblems relay information regarding potential shortage penalty costs to the ring design decisions. This naive implementation performs very poorly due to two major problems: (1) the weakness of the master problem relaxations, and (2) the limited information passed to the master problem by the optimality cuts. Accordingly, we enforce certain necessary conditions regarding shortage penalty contributions to the objective function within the master problem, along with a corresponding set of valid inequalities that improves the solvability of the master problem. We also show how a nonlinear reformulation of the model can be used to capture an exponential number of optimality cuts generated by the linear model. We augment these techniques with a powerful upper‐bounding heuristic to further accelerate the convergence of the algorithm, and demonstrate the effectiveness of our methodologies on a test bed of randomly generated stochastic SONET instances. © 2004 Wiley Periodicals, Inc. NETWORKS, Vol. 44(1), 12–26 2004
Management‐capacity building in the Pittsburgh region
Authors: Kearns Kevin P. 
Published: May 2004

AbstractThis article describes the strategy for management‐capacity building employed by The Forbes Funds in Pittsburgh, Pennsylvania. Like many other cities, Pittsburgh's capacity‐building industry has grown dramatically in recent years and is somewhat fragmented. But The Forbes Funds, along with other philanthropic organizations, have played an important role in developing a coherent system of management support services for nonprofit organizations in the Pittsburgh area. The article concludes with lessons that can be applied in other regions of the country.
A comparison of red blood cell thiopurine metabolites in children with acute lymphoblastic leukemia who received oral mercaptopurine twice daily or once daily: A Pediatric Oncology Group study (now The Children's Oncology Group)
Authors: Bell B.A. , Brockway G.N. , Shuster J.J. , Erdmann G. , Sterikoff S. , Bostrom B. , Camitta B.M. 
Published: May 2004

AbstractIntroductionMercaptopurine is an important antimetabolite for treatment of childhood acute lymphoblastic leukemia (ALL). It has been prescribed to be given daily without therapeutic monitoring of drug levels. After first‐pass metabolism by hepatic xanthine oxidase (XO), mercaptopurine is converted into two major intracellular metabolites, thioguanine nucleotide (TGN) and methylated mercaptopurine metabolites (including methylated thioinosine nucleotides), which are cytotoxic in vitro. Its short plasma half‐life and S‐phase‐dependent pharmacokinetics suggest that biologically active concentration and exposure duration may be critical to cell kill.MethodsPediatric Oncology Group (POG) 9605, a randomized, open label phase III study of standard‐risk ALL, was designed to compare daily with twice‐daily mercaptopurine during continuation therapy. Red blood cell (RBC) TGN and methylated mercaptopurine metabolite levels were measured as surrogates of leukemic cell levels in a randomly selected subset of patients. TGN and methylated mercaptopurine metabolites were analyzed quantitatively by high‐performance liquid chromatography (HPLC) and reported in ng/8 × 10.8 RBC. Statistical inferences utilized multiple linear regression.ResultsOne hundred eighteen patients received mercaptopurine 75 mg/m2 daily and 108 received 37.5 mg/m2/dose twice daily. Descriptive statistics for the daily group showed the median TGN was 42 ng (mean and standard deviation [SD] = 48 ± 35, quartiles 29–64). For the twice daily group, it was 40 ng (mean and SD = 40 ± 27, quartiles 26–53). For methylated mercaptopurine metabolites, the daily group median was 2,020 ng (mean and SD = 2,278 ± 1,559, quartiles 1,247–3,162); the twice daily group median was 1,275 ng (mean and SD = 1,580 ± 1,240, quartiles 599–2,369). When adjusted for the covariables: actual dosage, days on study, age at diagnosis, white blood cell count, gender, Black race compared with not, and Hispanic compared with not, daily dosing resulted in significantly higher average methylated mercaptopurine metabolites by 668 (standard error [SE] = 179, P = 0.001) and a trend toward higher average TGNs by 6.2 (SE = 4.2, P = 0.14).ConclusionsDaily dosing of mercaptopurine resulted in higher mean red cell methylated mercaptopurine metabolites when compared to split (twice a day dosing). The data were inconclusive with respect to TGNs. The relationships of methylated mercaptopurine metabolites and TGNs to clinical outcomes will be elucidated as part of the maturing 9605 data. © 2004 Wiley‐Liss, Inc.
Quality‐adjusted survival: A rigorous assessment of cure after cancer during childhood and adolescence
Authors: Barr Ronald D. , Sala Alessandra 
Published: May 2004

AbstractSurvivors of cancer in childhood and adolescence, while increasing gratifyingly in number with ever more effective therapy, have a life expectancy that is compromised all‐too‐often in both duration and value as a result of adverse treatment‐related sequelae. Accounting for this burden of morbidity and mortality is essential for a proper appreciation of cure. Adjusting estimates of survival by measures of its quality affords a means of accomodating this requirement. It can be accomplished by “weighting” the length of survival according to preference‐based assessments of health‐related quality of life (HRQL), which allow the calculation of quality‐adjusted life years. Inclusion of measures of HRQL in clinical trials is imperative as we reach to the ultimate objective; the truly cured child restored to normal health. © 2004 Wiley‐Liss, Inc.
Prospective audit of the introduction of insulin glargine (Lantus) into clinical practice in type 1 diabetes
Authors: Gallen I , Carter C 
Published: May 2004

AbstractThe aim of this study was to test whether the reported therapeutic benefits of insulin glargine over older basal insulins are also observed in routine clinical practice.Eighty‐five people with type 1 diabetes were transferred from isophane insulin to insulin glargine between August and December 2002. Selection indications included nocturnal hypoglycaemia, fasting hyperglycaemia, the need for two isophane injections, unusual patterns of receiving insulin therapy or a personal desire to receive insulin glargine. Subject details, including glycaemic control (glucose concentrations and HbA1c levels), were recorded. Questionnaires on the frequency of all hypoglycaemic and severe hypoglycaemic episodes (requiring assistance from a third party) were recorded. Assessments on treatment satisfaction (Diabetes Treatment Satisfaction Questionnaire [DTSQ]), quality of life and well‐being (Well‐being Questionnaire 28 [W‐BQ28]) were also performed. Subjects were re‐assessed after receiving insulin glargine for six months.Morning blood glucose concentrations and HbA1c levels fell significantly, from 9.87±0.39 to 7.93±0.29 mM (p<0.001) and from 8.24±0.12 to 7.89±0.11 (p=0.001), respectively. Total hypoglycaemic episodes remained unchanged after transferral to insulin glargine, but the number of severe hypoglycaemic episodes fell from 18 to two (p=0.002). Aggregate DTSQ scores improved from 23.7±0.85 to 28.1±0.87 (p<0.001). Perceived energy levels, diabetes specific well‐being and total well‐being each improved significantly (p<0.001, p=0.006 and p=0.032, respectively).This study indicates that the therapeutic benefits of insulin glargine reported in clinical trials in type 1 diabetes are also observed in routine clinical practice. Copyright ©2004 John Wiley & Sons, Ltd.
Thiol‐catalysed hydrolysis of cephalosporins and possible rate‐limiting amine anion expulsion
Authors: Llinás Antonio , Vilanova Bartolomé , Page Michael I. 
Published: May 2004

AbstractThe rates of thiolysis of cephalosporins were investigated by high‐performance liquid chromatography and1H NMR spectroscopy. Thiols catalyse the hydrolysis through the formation of a thioester intermediate and the catalytically reactive form of the thiol is the thiolate anion. Variation of nucleophilic reactivity by changing the basicity of the thiolate anion generates a Brønsted βnucvalue of 1.22 with cephaloridine, indicating that the breakdown of the tetrahedral intermediate is the rate‐limiting step. The effect of C3′ substituents on the rate of thiolysis of cephalosporins generates a large Hammett ρ of ca 12, which is compatible with C—N bond fission occurring without protonation of the β‐lactam nitrogen. Solvent kinetic isotope effectsk/kof ca 1.1 also indicate that solvent water probably does not act as a general acid catalyst facilitating breakdown of the tetrahedral intermediate by protonating the departing amine. Copyright © 2004 John Wiley & Sons, Ltd.
The path to the transition state in enzyme reactions: a survey of catalytic efficiencies
Authors: Snider Mark G. , Temple Brenda S. , Wolfenden Richard 
Published: May 2004

AbstractA survey of kcat/Km values supports the view that most enzymes combine with substrates at rates that approach the limits imposed by diffusional encounter. The closeness of that approach precludes the obligate participation of any rare species of the substrate, or any rare species of the enzyme, in productive binding. Proceeding from the ground state through the transition state, the enzyme–substrate complex is assumed to remain in a state of quasi‐equilibrium with the free enzyme and the unbound substrate in solution. Because the forces of attraction between an enzyme and substrate approach a maximum in the transition state for substrate transformation, the enzyme and substrate are also likely to approach a maximal state of distortion from their native ground‐state structures at that stage in the reaction, furnishing a natural explanation of induced fit. There is now abundant evidence, from mutations of enzymes and substrates, that interactions between the enzyme and substrate, using ordinary chemical forces of attraction, are so strongly synergistic that they may suffice to explain the very high affinities that are achieved in the transition state. Copyright © 2004 John Wiley & Sons, Ltd.
Flash photolytic generation and study of p‐quinone α‐phenylmethide and p‐quinone α,α‐diphenylmethide in aqueous solution
Authors: Chang J. A. , Kresge A. J. , Zhan H.‐Q. , Zhu Y. 
Published: May 2004

Abstractp‐Quinone α‐phenylmethide (7) and p‐quinone α,α‐diphenylmethide (8) were generated by flash photolytic dehydration of p‐hydroxy‐α‐phenylbenzyl alcohol (9, R1 = Ph, R2 = H) and p‐hydroxy‐α,α‐diphenylbenzyl alcohol (9, R1 = R2 = Ph) respectively, and rates of their decay were measured in aqueous perchloric acid and sodium hydroxide solutions and also as in acetic acid, biphosphate ion, tris(hydroxymethyl)methylammonium ion, ammonium ion and bicarbonate ion buffers. The rate profiles for the hydration of these quinone methides that these data provide show hydronium ion and hydroxide ion‐catalyzed regions and also ‘uncatalyzed’ water reactions, with saturation of hydronium ion catalysis in dilute solution for the diphenyl‐substituted substrate but only in concentrated acid solution for the less basic monophenyl substrate. Both substrates also give inverse hydronium ion isotope effects (kH+/kD+ < 1). These results show that the hydronium ion‐catalyzed reactions occur by rapid pre‐equilibrium protonation of the quinone methide on its carbonyl oxygen atom followed by rate‐determining capture of the benzyl‐type carbocation thus formed by water. Phenyl substitution retards the rate of hydration and also reduces the acidity constant of the quinone methide conjugate acid. The molecular basis of these substituent effects is discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Strong hydrogen bonding in chymotrypsin and other serine proteases
Authors: Frey Perry A. 
Published: May 2004

AbstractThe hydrogen bond linking His57‐Nδ1 and Asp102‐Oδ1 in chymotrypsin (Cht) at low pH and in transition state analogue complexes of Cht with peptide trifluoromethylketones (peptide‐TFKs) at pHs up to 12 has been assigned as a low barrier hydrogen bond (LBHB). The hydrogen bonds in these species of Cht display the physicochemical properties of LBHBs, as follows: 1) The proton NMR signals are far downfield, 18.1 ppm for Cht at low pH and 18.6–18.9 ppm for peptide‐TFK complexes. 2) The D/H fractionation factors are low, 0.3–0.4 for the peptide‐TFK complexes. 3) The deuterium and tritium isotope shifts (δD–δH, δT–δH) are negative. 4) The enthalpies of activation for solvent exchange (ΔHex) are high, 10–19 kcal mol−1. The LBHB is postulated to increase the base strength of His57 in the transition state for the nucleophilic addition of Ser195 to the peptide acyl group of a substrate. This property of His57 is displayed by His57 in the complexes of Cht with peptide‐TFKs, in which its pKa lies between 10.6 and 12 depending on the structure of the peptide. These values are optimal for an acid/base catalyst that both abstracts a proton from Ser195 in the formation of the tetrahedral intermediate and donates a proton to the leaving N‐terminal amino group in the decomposition of the tetrahedral intermediate. Strong hydrogen bonds in simple molecules can be studied in both aqueous and nonaqueous solutions, and the conditions for their existence are discussed. Copyright © 2004 John Wiley & Sons, Ltd.