bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of age on clinical care pathway length of stay after complex head and neck resection
Authors: Kagan Sarah H. , Chalian Ara A. , Goldberg Andrew N. , Rontal Matthew L. , Weinstein Gregory S. , Prior Barbara , Wolf Patricia F. , Weber Randal S.
Published: October 2002

Objective

This article investigates the effect of patient age on postoperative pathway length of stay (LOS) for head and neck surgery. Aggregate clinical results for 43 patients, enrolled in the CCP from June 1996–July 1997, are described. Patient age, comorbid status, and postoperative complications are analyzed with respect to impact on LOS.

Setting

Tertiary level academic medical center with an operative otorhinolaryngology volume of approximately 1200 cases per year.

Patients

Forty‐three patients undergoing head and neck resection with primary closure, local flap, or free flap closure were enrolled on CCP from June 1996–July 1997. Length of stay, frequency of selected aggregated comorbidities, and frequencies of complications are analyzed with nonparametric statistics. A pre‐pathway group of 87 consecutive patients is used for comparison.

Main Outcome Measures

Length of stay and age.

Results

Median actual LOS post‐pathway for the patients enrolled in the first year of the pathway was 8 days. This met the CCP target and improved on pre‐pathway LOS by 5 days (p < .001). The average LOS increased 25% from 8 days to 10 days for patients older than 65 years of age (p = .036, Mann–Whitney U test). Presence of a comorbidity and a complication concomitantly was statistically associated with increased LOS though not with advancing age (p = .003).

Conclusions

The CCP‐reported performance improvement achieved by this pathway suggests improved resource use, and improved patient outcomes are achieved for postoperative care of head and neck surgery patients. Our experience suggests that advancing age creates a clinically significant increase in resource use represented by our finding of increasing LOS. This finding warrants further investigation. © 2002 Wiley Periodicals, Inc. Head Neck 24: 545–548, 2002
The sarcomatous guise of cervical ectopic hamartomatous thymoma
Authors: Marschall Jeff , Kanthan Rani
Published: October 2002

Background

Ectopic hamartomatous thymoma is a rare benign neoplasm occurring in the deep soft tissues adjacent to the sternoclavicular joint. Although clinical presentation and diagnostic imaging can be consistent with a malignant lesion such as a sarcoma, recognition of pathologic features can readily exclude such a diagnosis. However, this remains a challenge caused by their unusual histologic features and diverse composition. Recognition of this tumor is, however, important, because it follows a benign clinical course, and conservative surgical excision is the therapy of choice.

Methods

A literature review of all reports of ectopic hamartomatous thymoma was undertaken and compared with our indexed case.

Results

From this review, we identified 26 previous reports. Most patients were men, with a 4.5:1 predominance. There was a wide range of ages at presentation, from 26 to 79 years. All tumors were located in the lower neck, with the exception of one arising presternally. Treatment predominantly consisted of tumor resection, with no reported recurrences on follow‐up.

Conclusions

We conclude that ectopic hamartomatous thymoma is an extremely rare neoplasm usually presenting in the lower neck. Correct identification of this tumor is important, because it follows a benign course, and surgical excision is adequate therapy. © 2002 Wiley Periodicals, Inc. Head Neck 24: 800–804, 2002
Multisource assessment programs in organizations: An insider's perspective
Authors: Brutus Stéphane , Derayeh Mehrdad
Published: October 2002

This study is an overview of multisource assessment (MSA) practices in organizations. As a performance
evaluation process, MSA can take various forms and can be complex for an organization to use. Although the
literature on MSA is extensive, little information exists on how these programs are perceived by the individuals
responsible for their implementation and maintenance. The purpose of this study was twofold: to describe the current
MSA practices used in organizations and to assess the issues associated with implementation and management of these
practices from the perspective of the individual responsible for managing an MSA program. One hundred one companies
located in Canada were surveyed for the study; almost half of these organizations (43 percent) were
using MSA. Interviews of managers responsible for MSA in various organizations and some archival data on these
organizations were the main source of data for the study. The study revealed that the use of MSA differs widely from
one company to another. In addition, results show that, once implemented, MSA requires a number of adjustments. The
source of these adjustments centered on employee resistance, lack of strategic purpose for MSA, poor design of the
instrument, and problems with the technology used to support MSA. These results are discussed and a proposed
research agenda is outlined.
Cytochrome P450 2D6 genotype does not predict SSRI (fluoxetine or paroxetine) induced hyponatraemia
Authors: Stedman Catherine A. M. , Begg Evan J. , Kennedy Martin A. , Roberts Rebecca , Wilkinson Timothy J.
Published: October 2002

Aims

The aims of this study were to determine if patients with SSRI‐related hyponatraemia were (1) genetically poor metabolizers of CYP2D6, and/or (2) had excessive plasma concentrations of the SSRI antidepressant.

Methods

Plasma DNA from 20 people with hyponatraemia attributable to fluoxetine or paroxetine was analysed for the CYP2D6 alleles *1–*16. Trough plasma concentrations of fluoxetine and norfluoxetine, or paroxetine were assayed in nine people who remained on the antidepressant.

Results

Genotype results were compared with those published in a large population study. The poor metabolizer PM/PM genotype was present in one subject only, or 5% of the study population, compared with 7.2% of a general population. The 95% Cl of this result was 0–21%, suggesting that it is most unlikely that hyponatremia is related to the PM/PM genotype. The intermediate IM/PM genotype was present in 5% compared with 19.7% of a general population. All differences were not statistically significant. Antidepressant concentrations of fluoxetine (n = 5, all EM) and paroxetine (n = 1 IM/PM and n = 3 EM) were all within the lower half of the reference range.

Conclusions

These results do not support the hypothesis that SSRI‐related hyponatraemia is linked to genetically poor metabolizers, or excessive drug concentrations. Copyright © 2002 John Wiley & Sons, Ltd.
Operational snowmelt runoff forecasting in the Spanish Pyrenees using the snowmelt runoff model
Authors: Gómez‐Landesa E. , Rango A.
Published: October 2002

The snowmelt runoff model (SRM) is used to simulate and forecast the daily discharge of several basins of the Spanish Pyrenees. We describe a method for snow mapping using NOAA–AVHRR data and a procedure to estimate retrospectively the accumulated snow water equivalent volume with the SRM. A linear combination of NOAA channels 1 and 2 is used to obtain a snow cover image in which the product is the percentage of the snow‐covered area in each pixel. Real‐time snowmelt forecasts are generated with the SRM using area snow cover as an input variable. Even in basins with a total absence of historical discharge and meteorological data, the SRM provides an estimation of the daily snowmelt discharge. By integrating the forecasted streamflow over the recession streamflow, snowmelt volume is obtained as a function of time. This function converges asymptotically to the net stored volume of water equivalent of the snowpack. Plotting this integral as a function of time, it is possible to estimate for each basin both the melted snow water equivalent (SWE) and the SWE remaining in storage at any point in the snowmelt season Spanish hydropower companies are using results from the SRM to improve water resource management. Copyright © 2002 John Wiley & Sons, Ltd.
Extreme rainfall in a changing climate: regional analysis and hydrological implications in Tuscany
Authors: Crisci A. , Gozzini B. , Meneguzzo F. , Pagliara S. , Maracchi G.
Published: October 2002

A comprehensive analysis of the extreme rainfalls in Tuscany, Italy, is carried out with the aim of understanding and quantifying the uncertainties connected with the estimation of the design storms, which is very important for a sound basin management at urban or larger scales. The historical extreme rainfall series of durations 1, 3, 6, 12 and 24 h collected at 81 rain gauges located at representative sites in Tuscany are computed to detect a possible trend by means of two tests: the Pearson linear correlation coefficient and the Mann–Kendall test. The generalized extreme value distribution is employed to compute design storms with a 30 years return period; hence a preliminary map of the most hazardous areas is built up. The design storms are then computed for several consecutive 20 year moving time windows (1 year step) to evaluate intrinsic (climatological) uncertainties in the series. A regionalization of the difference between the design storms calculated for different periods is performed. The hydrological consequences of this kind of climate variability are demonstrated to have a major impact on the design of hydraulic works in a basin. Copyright © 2002 John Wiley & Sons, Ltd.
Implications of heterogeneous flood‐frequency distributions on traditional stream‐discharge prediction techniques
Authors: Alila Younes , Mtiraoui Ahmed
Published: October 2002

Traditional flood‐frequency analysis involves the assumption of homogeneity of the flood distribution. However, floods are often generated by heterogeneous distributions composed of a mixture of two or more populations. Differences between the populations may be the result of a number of factors, including seasonal variations in the flood‐producing mechanisms, changes in weather patterns resulting from low‐frequency climate shifts and/or El Niño/La Nina oscillations, changes in channel routing owing to the dominance of within‐channel or floodplain flow, and basin variability resulting from changes in antecedent soil moisture. Not recognizing these physical processes in conventional flood‐frequency analysis probably is the main reason that many frequency distributions do not provide an acceptable fit to flood data. In this paper, we use long‐term hydroclimatic records from the Gila River basin of south‐east and central Arizona in the USA to explore the extent and significance of mixed populations. First, we discuss the probable causes of heterogeneity in the frequency distribution of annual flood and present evidence of its occurrence. Second, we investigate the implications of using various popular homogeneous distributions for predicting peak flows for basins that exhibit mixed population characteristics. Third, we demonstrate how alternative frequency models that explicitly account for floods generated by a mixture of two or more populations are both hydrologically and statistically more appropriate. We illustrate how the selection of the most plausible distribution for flood‐frequency analysis also should be based on hydrological reasoning as opposed to the sole application of the traditional statistical goodness‐of‐fit tests. Copyright © 2002 John Wiley & Sons, Ltd.
Towards a conceptual model of hydrological change on an abandoned cutover bog, Quebec
Authors: Van Seters Tim E. , Price Jonathan S.
Published: October 2002

Cutover bogs do not return to functional peatland ecosystems after abandonment because re‐establishment of peat‐forming mosses is poor. This paper presents a conceptual model of bog disturbance caused by peat harvesting (1942–1972), and the hydrological evolution that occurred after abandonment (1973–1998). Two adjacent bogs of similar size and origin, one harvested and the other essentially undisturbed, provide the basis for understanding what changes occurred. The model is based on historical trends evident from previous surveys of land‐use, bog ecology and resource mapping; and from recent hydrological and ecological data that characterize the current condition. Water balance data and historical information suggest that runoff increased and evapotranspiration decreased following drainage, but tended towards pre‐disturbance levels following abandonment, as vegetation recolonized the surface and drainage became less efficient over time. Dewatering of soil pores after drainage caused shrinkage and oxidation of the peat and surface subsidence of approximately 80 cm over 57 years. Comparisons with a nearby natural bog suggest that bulk density in the upper 50 cm of cutover peat increased from 0·07 to 0·13 g cm−3, specific yield declined from 0·14 to 0·07, water table fluctuations were 67% greater, and mean saturated hydraulic conductivity declined from 4·1 × 10−5 to 1·3 × 10−5 cm s−1. More than 25 years after abandonment, Sphagnum mosses were distributed over broad areas but covered less than 15% of the surface. Areas with ‘good’ Sphagnum regeneration (>10% cover) were strongly correlated with high water tables (mean −22 cm), especially in zones of seasonal groundwater discharge, artefacts of the extraction history. Forest cover expanded from 5 to 20% of the study area following abandonment. The effect of forest growth (transpiration and interception) and drainage on lowering water levels eventually will be countered by slower water movement through the increasingly dense soil, and by natural ditch deterioration. However, without management intervention, full re‐establishment of natural hydrological functions will take a very long time. Copyright © 2002 John Wiley & Sons, Ltd.
Novel camptothecin derivative BNP1350 in experimental human ovarian cancer: Determination of efficacy and possible mechanisms of resistance
Authors: van Hattum Annemarie H. , Schlüper Hennie M.M. , Hausheer Frederick H. , Pinedo Herbert M. , Boven Epie
Published: October 2002

The novel camptothecin derivative BNP1350 (7‐[2‐trimethylsilyl)ethyl]‐20(S)‐camptothecin), also known as Karenitecin, has been developed for superior oral bioavailability and increased lactone stability. In our study, we describe the antiproliferative effects of BNP1350, SN‐38 and topotecan in 4 human ovarian cancer cell lines. BNP1350 was found to be slightly more potent than SN‐38 (p<0.01) and was considerably more potent than topotecan (p<0.01). We extended these studies to well‐established human ovarian cancer xenografts in which we compared the growth inhibition induced by BNP1350 with that of topotecan given in equitoxic schedules. The growth inhibition in all 3 xenografts induced by BNP1350 was ≥75%, which was significantly better than that resulting from topotecan (p<0.05). We then selected BNP1350‐resistant variants of the A2780 human ovarian cancer cell line, 2780K4 (resistance factor: 41) and 2780K32 (resistance factor: 90), to analyze possible resistance mechanisms. These variants exhibited cross‐resistance against all camptothecins tested. In comparison with 2780K4 cells, 2780K32 cells were relatively more resistant against SN‐38, topotecan, DX‐8951f and BNP1350. In addition, 2780K32 cells were highly cross‐resistant against mitoxantrone. In both 2780K4 and 2780K32, the amount of topoisomerase I was not changed but the catalytic activity was reduced. Furthermore, 2780K32 cells clearly overexpressed the breast cancer resistance protein (BCRP), as demonstrated for both the gene and the protein. In contrast to topotecan, BNP1350 proved not to be a good substrate for BCRP. Overall, we conclude that BNP1350 offers advantages over topotecan expressed by high efficacy in experimental human ovarian cancer and poor affinity for BCRP. © 2002 Wiley‐Liss, Inc.
Attributable risks for familial breast cancer by proband status and morphology: A nationwide epidemiologic study from Sweden
Authors: Hemminki Kari , Granström Charlotta , Czene Kamila
Published: October 2002

Population attributable factions (PAFs) show the proportion of the disease that could be prevented if the cause could be removed. The PAF for familial breast cancer has not been precisely determined. We used the nationwide Swedish Family‐Cancer Database on 10.2 million individuals and 190,000 mothers' and 26,000 daughters' breast cancers to calculate familial standardized incidence ratios (SIRs), proportion of cases with a family history and familial PAFs for all invasive and in situ and morphology‐specific breast cancers in daughters who were 0–66 years old. The data were calculated by mother only, sister only or both as probands. More than 5,500 familial breast cancers were recorded. The familial SIRs for all invasive breast cancer were 1.79 by breast cancer in the mother only, 2.03 by breast cancer in a sister only and 2.82 by breast cancer in both a mother and sister. The familial PAFs were 3.61, 3.01 and 0.43%, respectively, giving a total PAF of 7.05%. Age‐specific risks were shown for the mother and sister history of breast cancer. The PAF values decreased by age when the daughter had a mother history of breast cancer but not when she had a sister history. PAFs did not depend on the morphologic type of breast cancer. The data show that the familial PAF of breast cancer among a 0–66‐year‐old population of daughters was 7% and independent of the morphologic type. If contribution from the paternal side was allowed for, the PAF would be 11%. © 2002 Wiley‐Liss, Inc.
Single‐nucleotide polymorphism in the E‐cadherin gene promoter modifies the risk of prostate cancer
Authors: Verhage Bas A.J. , van Houwelingen Kjeld , Ruijter T. Emiel G. , Kiemeney Lambertus A. , Schalken Jack A.
Published: October 2002

E‐cadherin plays a major role in intercellular adhesion, cell polarity and tissue architecture. We determined the relative risk of PCa associated with a previously reported C/A SNP at −160 bp relative to the transcription‐start site of the E‐cadherin gene promoter. Eighty‐two PCa patients and 188 controls were genotyped. Genotype and allele frequencies differed significantly among cases and controls. A‐allele carriers had a higher relative risk of PCa (OR = 3.6, 95% CI 2.0–6.4) compared to C‐only carriers. AC and AA genotypes had an increased risk of PCa (OR = 3.8, 95% CI 2.1–6.8 and OR = 1.7, 95% CI 0.4–6.6, respectively) compared to CC genotypes. © 2002 Wiley‐Liss, Inc.
Risk of invasive cervical cancer associated with polymorphic HLA DR/DQ haplotypes
Authors: Ghaderi Mehran , Wallin Keng‐Ling , Wiklund Fredrik , Zake Liene Nikitina , Hallmans Göran , Lenner Per , Dillner Joakim , Sanjeevi Carani B.
Published: October 2002

The genes encoding human leukocyte antigens (HLA) have shown to be associated with cervical neoplasia. To obtain reliable data on HLA associations with cervical tumors, the study should be performed within a strictly defined cohort. To investigate the population attributable risk of cervical cancer associated with the HLA class II haplotypes DR15 and DQ6 (DQA1*0102 and DQB1*0602), we performed a nested case‐control study of 85 women who developed invasive cervical cancer and 120 healthy women from a population‐based cohort of Swedish women. The relative risks of cervical cancer among DR15 and DQ6‐positive women were 3.73 [confidence interval (CI): 1.8–7.4] and 4.33 (CI: 2.1–8.5), corresponding to population attributable proportions of 27.9% and 30.8%, respectively. A susceptibility locus in the HLA class II region is involved in a substantial fraction of the etiology of cervical cancer. © 2002 Wiley‐Liss, Inc.
The importance of maternal state of mind regarding attachment and infant age at placement to foster mothers' representations of their foster infants
Authors: Bates Brady C. , Dozier Mary
Published: October 2002

Previous research has found that foster mother state of mind with respect to attachment and infant age at placement into foster care influence the developing foster mother–foster child relationship (Dozier, Albus, Stovall, & Bates, 2000; Stovall & Dozier, 2000). This study extends prior research by assessing factors related to foster mothers' representations of their foster infants. Participants were 48 foster mother–foster infant dyads in two mid‐Atlantic cities. We expected that foster mothers' states of mind and infant age at placement would be associated with foster mothers' acceptance of infants, commitment to infants, and belief in their influence on infants' development. Consistent with hypotheses, foster mothers' states of mind interacted with infant age at placement in predicting foster mothers' acceptance of their babies, and the extent to which foster mothers believed they could influence their infants' development. Specifically, autonomous foster mothers of babies placed before 12 months of age were more accepting and more likely to believe they could influence their infants' development compared to autonomous foster mothers of babies placed after 12 months of age, a pattern not seen for nonautonomous foster mothers. These results converge with other findings suggesting that timing of placement in foster care, and foster mothers' states of mind, are important to the developing foster mother–child relationship. ©2002 Michigan Association for Infant Mental Health.
Six‐month follow‐up of two mother–infant psychotherapies: Convergence of therapeutic outcomes
Authors: Cohen Nancy J. , Lojkasek Mirek , Muir Elisabeth , Muir Roy , Parker Carol Jane
Published: October 2002

Fifty‐eight mothers and infants participating in two infant–mother psychotherapeutic interventions in a comparative infant–mother clinical intervention study were followed six months after treatment ended. One treatment was an infant‐led psychotherapy, Watch, Wait, and Wonder (WWW). The other was a more traditional mother–infant psychodynamic psychotherapy (PPT). Infants ranged in age from 10 to 30 months at the outset of treatment, which took place in weekly sessions over approximately five months. Results indicated that positive effects observed from the beginning to the end of treatment in both treatment groups in infant symptoms, parenting stress, and mother–infant interaction were maintained or improved further at six‐month follow‐up. Additionally, decreased maternal depression, gains in infant cognitive development and emotion regulation, and improved infant–mother attachment security or organization had been observed posttreatment only in the WWW group. Interestingly, between the posttreatment to follow‐up period the PPT group also showed such gains. Thus, for these variables it would be more accurate to say that the outcomes were similar for the two treatment groups but change emerged at a different pace. Nevertheless, an advantage persisted in the WWW group in relation to mothers' comfort dealing with infant behaviors and their ratings of parenting stress which improved more in this group from the end of treatment to follow‐up. The direct inclusion of the infant as an initiator in WWW was set forth as an explanation of differentially timed treatment effects. ©2002 Michigan Association for Infant Mental Health.
E‐controlling: Ten Challenges for Controlling and Management Accounting
Authors: Erben Roland Franz
Published: October 2002

To keep pace with a rapidly changing and increasingly complex business environment, companies need to adapt and

modify their tool sets for strategic management accounting. On an operational level, the widespread use of modern

information and communication technologies has enabled a radical redesign of business processes. Modern

information and communication technologies can help leverage the efficiency of accounting and controlling

processes. © 2002 Wiley Periodicals, Inc.
Inhibition of the p38 pathway upregulates macrophage JNK and ERK activities, and the ERK, JNK, and p38 MAP kinase pathways are reprogrammed during differentiation of the murine myeloid M1 cell line
Authors: Hall J. Perry , Davis Roger J.
Published: October 2002

Mitogen‐activated protein (MAP) kinases have been implicated as important mediators of the inflammatory response. Here we report that c‐Jun NH2‐terminal kinase (JNK), extracellular signal‐regulated kinase (ERK), and p38 MAP kinase activities are reprogrammed during the IL‐6 induced macrophage‐like differentiation of the murine myeloid M1 cell line. Moreover, p38 inhibition upregulates JNK and ERK activity in M1 cells and in thioglycollate‐elicited peritoneal exudate macrophages. IL‐6‐induced M1 differentiation also induces expression of the anti‐inflammatory cytokine IL‐10, and p38 inhibition potentiates this increase in IL‐10 expression in an ERK‐dependent manner. Thus, we speculate that during inflammatory conditions in vivo macrophage p38 may regulate JNK and ERK activity and inhibit IL‐10 expression. These data highlight the importance of p38 in the molecular mechanisms of macrophage function. J. Cell. Biochem. 86: 1–11, 2002. © 2002 Wiley‐Liss, Inc.
Nuclear matrix proteins as biomarkers in prostate cancer
Authors: Leman Eddy S. , Getzenberg Robert H.
Published: October 2002

The nuclear matrix (NM) is the structural framework of the nucleus that consists of the peripheral lamins and pore complexes, an internal ribonucleic protein network, and residual nucleoli. The NM contains proteins that contribute to the preservation of nuclear shape and its organization. These protein components better known as the NM proteins have been demonstrated to be tissue specific, and are altered in many cancers, including prostate cancer. Alterations in nuclear morphology are hallmarks of cancer and are believed to be associated with changes in NM protein composition. Prostate cancer is the most frequently diagnosed cancer in American men and many investigators have identified unique NM proteins that appear to be specific for this disease. These NM protein changes are associated with the development of prostate cancer, as well as in some cases being indicative of cancer stage. Identification of these NM proteins specific for prostate cancer provides an insight to understanding the molecular changes associated with this disease. This article reviews the role of NM proteins as tumor biomarkers in prostate cancer and the potential application of these proteins as therapeutic targets in the treatment of this disease. J. Cell. Biochem. 86: 213–223, 2002. © 2002 Wiley‐Liss, Inc.
1,25(OH)2D3‐mediated phosphate uptake in isolated chick intestinal cells: Effect of 24,25(OH)2D3, signal transduction activators, and age
Authors: Zhao Bin , Nemere Ilka
Published: October 2002

We have previously reported an absence of a 1,25(OH)2D3‐mediated effect on 45Ca handling by intestinal epithelial cells isolated from normal chicks (Nemere and Campbell [2000] Steroids 65:451–457). In the current work, we provide evidence that in similar cell preparations, 1,25(OH)2D3 increased 32P uptake within 5 min of addition, and reached 150% of controls after 10 min (P < 0.05). Both isolated enterocytes and the perfused duodenal loop system exhibited apparent biphasic dose–response curves for 1,25(OH)2D3‐stimulated 32P uptake and transport, and inhibition of stimulation by 24,25(OH)2D3. A comparison of signal transduction activators demonstrated the following parallels in both isolated intestinal cells and perfused duodena: lack of effect of forskolin (a protein kinase (PK) A activator) on 32P handling, but simulation by BAY K8644 (a calcium channel activator) and phorbol ester (a PKC activator). Finally, we tested the effect of 1,25(OH)2D3 on phosphate uptake in epithelial cells isolated from birds of increasing ages (7, 14, and 28 wk). In contrast to the robust response of cells from young, growing chicks, 1,25(OH)2D3 had no effect on enterocytes from 14 or 28 wk birds. Western analyses with Ab 099 against the 1,25(OH)2D3 (1,25D3)‐Membrane‐Associated Rapid Response Steroid (MARRS) binding protein revealed a decrease in average density of the immunoreactive band with age. PKC activity determined in isolated epithelial cells exhibited a decrease in average basal (control) activity with age, as well as a decrease in response to 1,25(OH)2D3 activation. In enterocytes from 7–14‐ or 28‐week birds, PKC was enhanced 170, 120, and 105% of controls, respectively. The combined data validate 32P uptake in isolated enterocytes as a model system to study 1,25D3‐MARRS protein function, and indicate that for phosphate transport, the rapid actions of 1,25(OH)2D3 are physiologically more important in growing animals than immature ones. J. Cell. Biochem. 86: 497–508, 2002. © 2002 Wiley‐Liss, Inc.
FA(I):Au+andFA(II):Cu+laser activity and photographic sensitization at the low coordinated surfaces of AgBrab initiocalculations
Authors: Shalabi A. S.
Published: October 2002

The twofold potentials ofFA(I):Au+andFA(II)Cu+color centers at the low coordinated surfaces of AgBr thin films in providing tunable laser activity and photographic sensitization were investigated usingab initiomethods of molecular electronic structure calculations. Clusters of variable size were embedded in simulated Coulomb fields that closely approximated the Madelung fields of the host surfaces, and the nearest neighbor ions to theFAdefect site were allowed to relax to equilibrium in each case. Based on the calculated Stokes shifted optical transition bands and horizontal shifts along the configuration coordinate diagrams, bothFA(I):Au+andFA(II):Cu+color centers were found to be laser active. The laser activity faded quickly as the bromide ion coordination decreased from 5 (flat) to 4 (edge) to 3 (corner) and as the size of the impurity cation increased from Cu+to Au+. The latter relation was explainable in terms of the axial perturbation of the impurity cation. The smallest calculated Stokes‐shift at the corner surface suggested that emission had the same oscillator strength as absorption. All relaxed excited states RESs of the defect containing surfaces were deep below the lower edges of the conduction bands of the defect free ground state surfaces, indicating thatFA(I):Au+andFA(II):Cu+are suitable laser defects. The probability of orientational destruction of the two centers attributed to the assumed RES saddle point ion configurations along the 〈110〉 axis was found to be directly proportional to the size of the impurity cation, with activation energy barriers of about 0.655–3.294 eV for Cu+, and about 1.887–3.404 eV for Au+. The possibility of exciton (energy) transfer from the sites of higher coordination to those of lower coordination is demonstrated. The more laser activeFA(II):Cu+center was more easily formed than the less laser activeFA(I):Au+center. The Glasner‐Tompkins empirical relation was generalized to includeFAcenters at the low coordinated surfaces of silver bromide thin film. As far as color photographic sensitization is concerned, the lowest unoccupied molecular orbitals of the selected dye molecules in the excited states were high enough for electron injection.FAdefect formation and rotational diffusion of silver clusters reduced the energy gaps between the excited dye molecules and the lower edges of the conduction bands and allowed for hole injection. About 54–60% of the reduction of silver ions at the flat surface of AgBr was attributed to the host anions andFAdefect formation, leaving about 40–46% for the reduction of photoelectrons as well as the electrons of the developer or dye molecules. The unrelaxed rotational diffusions of the central Ag4by 90° decreased the latter percentage, but were severely hindered by activation energy barriers. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 1104–1120, 2002
Relationships among perceptions of parent involvement, time allocation, and demographic characteristics: Implication for policy formation
Authors: Ritblatt Shulamit N. , Beatty James R. , Cronan Terry A. , Ochoa Alberto M.
Published: October 2002

Variables that facilitate or hinder parent involvement (PI) in education and schools were explored, along with the amounts of time parents spent in various activities. A total of 506 participants from San Diego and Imperial Counties completed the first part of the study (1) designed to assess parents' beliefs about involvement with their child's school and education. Of these same participants, 357 self‐selected parents also chose to complete a second part of the study (2) that assessed the amount of time parents spend in education‐related activities. Factor analysis of the 506 participant responses revealed four school perception factors related to parent attitudes: (a) communication, (b) familiarity, (c) sensitivity, and (d) support. Factor analysis of the 357 participant responses to the time factors also revealed four involvement areas: (a) general school issues, (b) specific school issues, (c) extracurricular school activities, and (d) specific help. Significant relationships were found among three of the attitudinal factors (sensitivity, familiarity, and support) and various time factors, including total involvement time, general issues, specific problems, and extracurricular issues. Further, significant differences among means were found for both the school perception factors and the time factors based on ethnic background, income, and marital status. Recommendations for increasing parent involvement and formulating public policy are discussed. © 2002 Wiley Periodicals, Inc.
Interagency teams: A vehicle for service delivery reform
Authors: Allen Nicole E. , Foster‐Fishman Pennie G. , Salem Deborah A.
Published: October 2002

Human service delivery organizations often have great difficulty implementing new service delivery technologies. This study examines the extent to which interagency service delivery teams facilitate the implementation of a popular reform that significantly challenges the status quo: family‐centered service delivery. Survey data from 121 providers representing 25 agencies within one county suggest that interagency teams may promote provider implementation of new service delivery practices. Teams members were more likely than nonteam members to implement practices consistent with family‐centered service delivery. Consumer focus group data support these findings, with consumers noting that services received from providers in the team context were more individualized, empowering, and comprehensive than the services they typically received in the county. The implications of these findings for practitioners and scholars interested in facilitating human service delivery reform are discussed. © 2002 Wiley Periodicals, Inc.
Epidermal expression of the full‐length extracellular calcium‐sensing receptor is required for normal keratinocyte differentiation
Authors: Komuves Laszlo , Oda Yuko , Tu Chia‐ling , Chang Wen Han , Ho‐Pao Chrystal L. , Mauro Theodora , Bikle Daniel D.
Published: October 2002

The importance of the extracellular calcium‐sensing receptor (CaR) in the stringent control of extracellular Ca2+ concentration is well established. However, the presence of CaR in tissues not directly involved in regulating mineral ion homeostasis such as the epidermis suggests a role for CaR in other cellular functions. Although extracellular Ca2+ regulates the differentiation of epidermal keratinocytes, the role of CaR in this process in the epidermis is not fully understood. In this study we showed using in situ hybridization and immunohistochemistry that CaR is expressed in suprabasal keratinocytes of the mammalian epidermis. We then evaluated the changes in epidermal keratinocyte morphology and differentiation in Casr−/− mice lacking the full‐length CaR. These mice show increased expression of an alternatively spliced form of CaR which lacks acute Ca2+‐signaling properties. The absence of the full‐length CaR in the epidermis resulted in ultrastructural changes (abnormal keratohyalin granule formation and precocious lamellar body secretion) in the terminally differentiated granular keratinocytes. Furthermore, the expression of both mRNA and protein for the calcium inducible keratinocyte differentiation markers, filaggrin and loricrin, were down‐regulated in the epidermis of Casr−/− mice, whereas the number of proliferating cells were increased even though the calcium gradient within the epidermis was enhanced. Our results demonstrate that the epidermal expression of the full‐length CaR is required for the normal terminal differentiation of keratinocytes. © 2002 Wiley‐Liss, Inc.
Ras family genes: An interesting link between cell cycle and cancer
Authors: Macaluso M. , Russo G. , Cinti C. , Bazan V. , Gebbia N. , Russo A.
Published: October 2002

Ras genes are evolutionary conserved and codify for a monomeric G protein binding GTP (active form) or GDP (inactive form). The ras genes are ubiquitously expressed although mRNA analysis suggests different level expression in tissue. Mutations in each ras gene frequently were found in different tumors, suggesting their involvement in the development of specific neoplasia. These mutations lead to a constitutive active and potentially oncogenic protein that could cause a deregulation of cell cycle. Ras protein moderates cellular responses at several mitogens and/or differentiation factors and at external stimuli. These stimuli activate a series of signal transduction pathways that either can be independent or interconnected at different points. Recent observations begin to clarify the complex relationship between Ras activation, apoptosis, and cellular proliferation. A greater understanding of these processes would help to identify the factors directly responsible for cell cycle deregulation in several tumors, moreover it would help the design of specific therapeutic strategies, for the control on the proliferation of neoplastic cells. We summarize here current knowledge of ras genes family: structural and functional characteristics of Ras proteins and their links with cell cycle and cancer. © 2002 Wiley‐Liss, Inc.
Angiopoietin‐2 plays an important role in retinal angiogenesis
Authors: Hackett Sean F. , Wiegand Stanley , Yancopoulos George , Campochiaro Peter A.
Published: October 2002

Angiopoietin 2 (Ang2) expression in the retina is increased during physiologic and pathologic neovascularization suggesting that it may be involved. In this study, we used Ang2‐deficient mice to test that hypothesis. Mice deficient in Ang2 showed delayed and incomplete development of the superficial vascular bed of the retina, which develops primarily by vasculogenesis, and complete absence of the intermediate and deep vascular beds which develop by angiogenesis. In addition to incomplete retinal vascular development, Ang2‐deficient mice showed lack of regression of the hyaloid vasculature, resulting in a phenotype that mimics infants with persistent fetal vasculature (PFV), a relatively common congenital abnormality. Exposure to high levels of oxygen resulted in partial regression of the retinal vessels, indicating that oxygen‐induced regression of retinal vessels does not require Ang2. When these oxygen‐exposed mice with few retinal vessels were moved to room air, there was no ischemia‐induced retinal neovascularization. These data support the hypothesis that Ang2 plays a critical role in physiologic and pathologic angiogenesis, and physiologic, but not oxygen‐induced vascular regression. The data also suggest that infants with PFV should be examined for genetic modifications that would be expected to cause perturbations in Tie2 signaling. © 2002 Wiley‐Liss, Inc.
Myelin phagocytosis by macrophages and nonmacrophages during Wallerian degeneration
Authors: Hirata Kazuho , Kawabuchi Masaru
Published: October 2002

The literature concerning Schwann cells (SCs) and macrophages in myelin phagocytosis during Wallerian degeneration is reviewed. SCs carry out the first step in the removal of myelin by segmenting myelin and then incorporating the degraded myelin. The recruited macrophages then join in the myelin‐phagocytosis event, appearing to make full use of their original phagocyte abilities until the end of myelin clearance. The molecular mechanisms of the two cells underlying myelin phagocytosis are thought to be different; myelin phagocytosis by SCs being lectin‐mediated, i.e., opsonin‐independent, whereas that of macrophages is mainly opsonin‐dependent. It is important to note that SCs and macrophages cooperatively accomplish myelin phagocytosis. Microsc. Res. Tech. 57:541–547, 2002. © 2002 Wiley‐Liss, Inc.
Appraisal of Sims applicability to boron studies in plants
Authors: Dérue Cedric , Gibouin David , Verdus Marie‐Claire , Lefebvre Fabrice , Demarty Maurice , Ripoll Camille , Thellier Michel
Published: October 2002

In the search for a new methodological approach applicable to the determination of the still poorly known primary role of boron in plant physiology, we have undertaken to appraise the potential of the SIMS method for the analytical imaging of the boron isotopes, 10B and 11B, at physiological concentrations in plants. With our own, CAMECA IMS4F SIMS ion analyser, and using O2+ as primary ions for the detection of B+ (plus 12C+ and 40Ca+) secondary ions, we have been able to map quantitatively the two boron isotopes in control and boron‐enriched plants, to evaluate boron concentrations at the level of individual cells and to determine boron isotopic ratios. This provides the opportunity to carry out the simultaneous labeling and imaging of boron, using enrichment with the stable isotopes, 10B and 11B. The method has also the potential for the simultaneous, quantitative detection of the boron isotopes and of the borate‐binding sites in plant cells. Microsc. Res. Tech. 58:104–110, 2002. © 2002 Wiley‐Liss, Inc.
Cellular and molecular biology of ensheathing cells
Authors: Chuah Meng Inn , West Adrian K.
Published: October 2002

Ensheathing cells are the glial cells that envelop olfactory axons as they course from the olfactory epithelium to the bulb. They are derived from the olfactory placode and differ from the typical glia in terms of sharing the phenotypes of both astrocytes and Schwann cells. The aims of this study are to review (1) cellular characterisation of ensheathing cells in vivo and in vitro, (2) molecular insight into their growth promoting properties, and (3) their role in olfactory development and potential function as a therapeutic agent for nerve repair. Much of the characterisation of ensheathing cell property has developed from immunohistochemical studies that have been supplemented with new molecular methodologies in recent years. Many pieces of evidence clearly indicate that ensheathing cells actively produce growth‐promoting molecules, which act in a paracrine and, in some cases, autocrine manner. However, a review of the available literature also suggests that there is a great deal that remains to be elucidated regarding the cell biology of ensheathing cells, for example, their rate of formation and turnover. In addition, the apparent antigenic heterogeneity as revealed by numerous in vitro studies warrants further analysis, particularly in view of the fact that in recent years these cells have been touted as a possible agent for central nerve repair. New molecular methodologies such as the microarray techniques will prove to be crucial for defining the unique characteristics of ensheathing cells. Microsc. Res. Tech. 58:216–227, 2002. © 2002 Wiley‐Liss, Inc.
Acceleration of Ambystoma tigrinum metamorphosis by corticotropin‐releasing hormone
Authors: BOORSE GRAHAM C. , DENVER ROBERT J.
Published: October 2002

Previous work of others and ours has shown that corticotropin‐releasing hormone (CRH) is a positive stimulus for thyroid and interrenal hormone secretion in amphibian larvae and that activation of CRH neurons may mediate environmental effects on the timing of metamorphosis. These studies have investigated CRH actions in anurans (frogs and toads), whereas there is currently no information regarding the actions of CRH on metamorphosis of urodeles (salamanders and newts). We tested the hypothesis that CRH can accelerate metamorphosis of tiger salamander (Ambystoma tigrinum) larvae. We injected tiger salamander larvae with ovine CRH (oCRH; 1 μg/day; i.p.) and monitored effects on metamorphosis by measuring the rate of gill resorption. oCRH‐injected larvae completed metamorphosis earlier than saline‐injected larvae. There was no significant difference between uninjected and saline‐injected larvae. Mean time to reach 50% reduction in initial gill length was 6.9 days for oCRH‐injected animals, 11.9 days for saline‐injected animals, and 14.1 days for uninjected controls. At the conclusion of the experiment (day 15), all oCRH‐injected animals had completed metamorphosis, whereas by day 15, only 50% of saline‐injected animals and 33% of uninjected animals had metamorphosed. Our results show that exogenous oCRH can accelerate metamorphosis in urodele larvae as it does in anurans. These findings suggest that the neuroendocrine mechanisms controlling metamorphosis are evolutionarily conserved across amphibian taxa. © 2002 Wiley‐Liss, Inc.
Synthesis of [1‐13C]‐para‐xylene and [2‐13C]‐para‐xylene
Authors: Mormann Michael , Kuck Dietmar
Published: October 2002

An efficient synthesis of [1‐13C]‐para‐xylene (1a) and [2‐13C]‐para‐xylene (1b) is described. The incorporation of the label has been achieved by cyclocondensation of suitable 1,5‐bis(bromomagnesio)alkanes with either ethyl [1‐13C]acetate or ethyl [13C]formate which gave [ring‐13C]‐labelled dimethylcyclohexanols. Dehydration of these alcohols followed by dehydrogenation of the intermediate dimethylcyclohexenes furnished the title compounds in 32 and 40% overall yield, respectively. Copyright © 2001 John Wiley & Sons, Ltd.
Ultrastructural observations of eu‐ and paraspermiogenesis in the cottid fish Hemilepidotus gilberti (Teleostei: Scorpaeniformes: Cottidae)
Authors: Hayakawa Youichi , Komaru Akira , Munehara Hiroyuki
Published: October 2002

The developmental process of eu‐ and paraspermatozoa in the cottid fish, Hemilepidotus gilberti, was observed by electron microscopy. Euspermatozoa of H. gilberti consist of a thin disk‐like sperm head (about 3 μm in length), a short middle piece, and a long flagellum, but lack an acrosome. On the other hand, during spermiogenesis, aberrant spermatids, rich in cytoplasm and possessing binuclei, develop into cysts containing spermatids. The developing aberrant spermatids connect with normal spermatids and euspermatozoa by intercellular bridges. The early phase of chromatin condensation in aberrant spermatids is almost identical to that in normal spermatids, but the nuclei in the later phase develop into a mass of highly electron‐dense globules. Since the aberrant spermatids complete karyokinesis but not cytokinesis at telophase of the second meiotic division, they are considered to develop into hyperpyrenic cells due to incomplete cytokinesis of the second meiotic division. These spermatids are oval in shape (5–7 μm in diameter) and lack a flagellum. The aberrant spermatids of H. gilberti are shed along with euspermatozoa and amount to about 50% of semen in volume. Judging from their form and developmental process, aberrant spermatids produced in H. gilberti are considered hyperpyrenic paraspermatozoa. J. Morphol. 253:243–254, 2002. © 2002 Wiley‐Liss, Inc.