bluuebunny/crossref_metadata_2025 huggingface dataset:
Recurrent allelic imbalance at the rat Pten locus in DMBA‐induced fibrosarcomas
Authors: Sjöling Åsa , Samuelson Emma , Adamovic Tatjana , Behboudi Afrouz , Röhme Dan , Levan Göran
Published: December 2002

The tumor‐suppressor gene PTEN (phosphatase and tensin homolog) is frequently inactivated in different types of human tumors. Less is known about the involvement of the homologous gene Pten in animal model systems of cancer. By sequencing one of the introns of rat Pten, we found an informative intragenic PCR marker suitable for genetic studies. Through use of this marker, the position of Pten in the genetic linkage map was localized to the distal part of rat chromosome 1 (RNO1) by analysis of F2 progeny from an intercross between inbred strains BN and LE. Subsequently, 22 markers from this region (including the intragenic Pten marker) were used to study the occurrence of allelic imbalance in distal RNO1 in fibrosarcomas that had been induced by DMBA in F1(BN×LE) rats. The analysis revealed that allelic imbalance was common in the vicinity of Pten, and there was loss or reduction of one of the Pten alleles in more than 60% of the fibrosarcomas. DNA sequencing was preformed to investigate whether the Pten allele remaining in the tumors was inactivated by mutation. However, no mutations were detected in the genomic sequence of Pten exons 5 to 9 in any of the fibrosarcomas, and normal mRNA transcripts were expressed in all tumors. Thus, based on the targeted selection for loss of Pten observed in some of these tumors and the absence of inactivation of the remaining allele, we suggest that haploinsufficiency of Pten may be an important factor in rat DMBA‐induced fibrosarcomas. © 2002 Wiley‐Liss, Inc.
Skill learning in patients with moderate Alzheimer's disease: a prospective pilot‐study of waltz‐lessons
Authors: Rösler Alexander , Seifritz Erich , Kräuchi Kurt , Spoerl David , Brokuslaus Ilona , Proserpi Sara‐Maria , Gendre Annekäthi , Savaskan Egemen , Hofmann Marc
Published: December 2002

The authors report the effect of a 12‐day prospective, blinded dance‐learning trial in 5 patients with moderate Alzheimer's disease (AD) and 5 age‐matched depressed patients. Patients with AD showed a significant effect in procedural learning whereas depressed patients did not. These findings suggest potential implications for therapeutic interventions in patients with moderate AD. Copyright © 2002 John Wiley & Sons, Ltd.
Qigong as a psychosocial intervention for depressed elderly with chronic physical illnesses
Authors: Tsang Hector W. H. , Cheung Leo , Lak Davis C. C.
Published: December 2002

Literature uncovers that depression is common in elderly people. The problem is more serious in elderly with chronic physical illnesses. Although the relationship between physical problems and depression is well documented, the underlying mechanism is basically unknown. This article proposed after a comprehensive literature review that depression in elderly with chronic physical illnesses results from disability and a reduction in psychosocial resources. If depression is left untreated, suicide may be a consequence. In view of this, various forms of psychosocial interventions are developed based on mainstream western medicine. The authors argue that qigong, a form of Chinese therapeutics, has the effect of alleviating clinical depression and thus improves quality of life. A simple form of dynamic qigong, namely the Eight‐Section Brocades, is suggested to serve the purpose. A theory which explains the psychosocial effect of qigong is hypothesized. Copyright © 2002 John Wiley & Sons, Ltd.
Quality of accommodation and risk of depression in later life: An analysis of prospective data from the Gospel Oak Project
Authors: Stewart Robert , Prince Martin , Harwood Rowan , Whitley Robert , Mann Anthony
Published: December 2002

Objective

To investigate the association between observer‐rated quality of internal accommodation and risk of onset of depression.

Design

A secondary analysis of data from a cross‐sectional survey of residents aged 65 or over in a north London electoral ward who were followed up after a one‐year interval.

Method

Pervasive depression (SHORT‐CARE) was assessed at both interviews. Quality of accommodation (on a five‐point scale) was assessed by a single interviewer in a random sample at baseline. Potential confounding factors which were considered included age, sex, social class, level of handicap, level of social support, baseline sub‐case depressive symptoms, cognitive function, income, accommodation tenure and area‐level housing quality.

Results

In participants without depression at baseline (n=131), worse accommodation was associated with depression after one year (odds ratio (OR) between three accommodation groups 3.3, 95% confidence intervals (CI) 1.5–7.8). Adjustment for the potential confounding factors made little difference (adjusted OR 3.3). The association was principally in people cohabiting (OR 12.4) rather than living alone (OR 1.1).

Conclusions

An observer's impression of accommodation quality was a strong and independent predictor of depression in this sample. The stronger association in people who were cohabiting may reflect increased exposure to the internal environment. Copyright © 2002 John Wiley & Sons, Ltd.
Antidepressant prescribing in nursing homes: is there a place for tricyclics?
Authors: Borson S. , Scanlan J. M. , Doane K. , Gray S.
Published: December 2002

Objective

To deduce a model describing physicians' choice of antidepressants for treating elderly nursing home patients.

Methods

Subjects were geriatric residents of 137 skilled nursing facilities who regularly received an antidepressant medication for at least one month (n = 3440, 28% of all residents). Reasons for prescribing antidepressants and physicians' diagnoses of depression and dementia were identified by medical record audit. Residents were grouped by dementia and antidepressant target symptoms (depression, or one or more non‐psychiatric symptoms, i.e. insomnia, pain, incontinence, itching).

Results

Selective serotonin reuptake inhibitors (SSRIs) were prescribed preferentially over tricyclic antidepressants (TCAs) for treating depression in both demented and non‐demented residents, but TCAs were nine times more likely to be prescribed for treating non‐psychiatric target symptoms alone. When non‐psychiatric target symptoms were present without depression or dementia, both amitriptyline and nortriptyline prescribing was increased, but amitriptyline appeared to be the antidepressant of choice. In all subgroups examined, its use was two to five times more prevalent when such symptoms were present. In patients with dementia, amitriptyline prescribing declined whether or not non‐psychiatric target symptoms were present, but nortriptyline prescribing did not; nortriptyline was three times more likely than amitriptyline to be prescribed in the presence of dementia.

Conclusions

Physicians prescribe anticholinergic TCAs principally to treat common non‐depressive symptoms in nursing home residents, preferring SSRIs for uncomplicated depression and depression with dementia. They tend to avoid prescribing anticholinergic TCAs other than nortriptyline when they recognize a patient as demented. The data suggest that physicians employ a decision model for antidepressant prescribing that simultaneously recognizes the utility of TCAs in treating non‐psychiatric symptoms and the anticholinergic vulnerability of older, especially demented, patients. Whether or not this model leads to optimal patient management requires further study. Copyright © 2002 John Wiley & Sons, Ltd.
Using extracurricular activity as an indicator of interpersonal skill: Prudent evaluation or recruiting malpractice?
Authors: Rubin Robert S. , Bommer William H. , Baldwin Timothy T.
Published: December 2002

There is widespread agreement that success in organizations requires more than high intellect. Thus, college
recruiters commonly examine job candidates' extracurricular activities in search of
“well‐rounded,” emotionally intelligent, and interpersonally skilled students. Intuitively,
extracurricular activities seem like valuable student experiences; however, research evidence is sparse,
suggesting far more questions than answers. Is participation in extracurricular activity truly linked to
interpersonal skill performance? Does leadership experience make a difference? Do extracurricular
experiences yield higher skill development? Six hundred eighteen business students and the relationship of
their extracurricular involvement to four interpersonal skills were examined. Significant relationships were found
and recruitment implications are discussed. © 2002 Wiley Periodicals, Inc.
BRCA2 arg372hispolymorphism and epithelial ovarian cancer risk
Authors: Auranen Annika , Spurdle Amanda B. , Chen Xiaoqing , Lipscombe Julian , Purdie David M. , Hopper John L. , Green Adele , Healey Catherine S. , Redman Karen , Dunning Alison M. , Pharoah Paul D. , Easton Douglas F. , Ponder Bruce A.J. , Chenevix‐Trench Georgia , Novik Karen L.
Published: December 2002

The BRCA2 372 HH genotype defined by the BRCA2 N372H nonconservative amino acid substitution polymorphism was recently reported to be associated with a small increased risk of breast cancer. We investigated whether this polymorphism was associated with ovarian cancer risk by conducting British and Australian case‐control comparisons in parallel, including a total sample of 1,121 ovarian cancer cases and 2,643 controls. There was no difference in genotype frequency between control groups from the 2 studies (p = 0.9). The HH genotype was associated with an increased risk of ovarian cancer in both studies, and the risk estimate for the pooled studies was 1.36 (95% CI 1.04–1.77, p = 0.03). There was also a suggestion that this risk may be greater for ovarian cancers of the serous subtype for both studies, with an OR (95% CI) of 1.66 (1.17–2.54) for the 2 studies combined (p = 0.005). The BRCA2 372 HH genotype appears to be associated with an increased risk of ovarian cancer of a similar magnitude to that reported for breast cancer. © 2002 Wiley‐Liss, Inc.
Geldanamycin decreases Raf‐1 and Akt levels and induces apoptosis in neuroblastomas
Authors: Kim Sunghoon , Kang Junghee , Hu Wanqin , Evers B. Mark , Chung Dai H.
Published: December 2002

Neuroblastomas are the most common extracranial solid tumors of childhood. These tumors are associated with an overall poor prognosis, particularly for advanced stage disease. The benzoquinone ansamycin antibiotic, geldanamycin (GA), exhibits potent antitumor activity in certain cancer cell lines by destabilizing important signal transduction proteins (e.g., Raf‐1 and Akt). The purpose of our study was to determine whether GA can alter the expression of Raf‐1 and Akt, which have been shown to be critical for neuronal cell survival, and induce apoptosis of neuroblastoma cells. Human neuroblastoma cells (SH‐SY5Y, SK‐N‐SH and LAN‐1) were treated with GA for a variable period of time. Cell viability was assessed with MTT assays. Apoptosis was assessed with DNA fragmentation ELISA, TUNEL‐flow cytometric assay, Western blot and caspase activities. We found that GA decreases cell viability and induces apoptosis in the SH‐SY5Y human neuroblastoma cell line. These effects were mediated through activation of caspase‐9 and ‐3, mitochondrial release of cytochrome c and subsequent PARP cleavage. GA‐induced apoptosis was associated with a reduction in the level and activity of Raf‐1 and Akt. The importance of these proteins was further demonstrated by induction of apoptosis in SH‐SY5Y cells by a combination of U0126 (MEK1/2 inhibitor) and LY294002 (an inhibitor of PI3K). Similar to SH‐SY5Y cells, other human neuroblastoma cells (SK‐N‐SH and LAN‐1) were sensitive to the effects of GA‐induced apoptosis. Taken together, our findings suggest that GA may be a novel therapeutic agent, which may be effective in the treatment of neuroblastomas. © 2002 Wiley‐Liss, Inc.
Prevalence of human papillomavirus infection in women in Busan, South Korea
Authors: Shin Hai‐Rim , Lee Duk‐Hee , Herrero Rolando , Smith Jennifer S. , Vaccarella Salvatore , Hong Sook‐Hee , Jung Kap‐Yeol , Kim Hyun‐Ho , Park Un‐Dong , Cha Hyung‐Su , Park Soyoon , Touzé Antoine , Muñoz Nubia , Snijders Peter J.F. , Meijer Chris J.L.M. , Coursaget Pierre , Franceschi Silvia
Published: December 2002

To investigate the prevalence of and the risk factors for human papillomavirus (HPV) infection in South Korea, we interviewed and examined a randomly selected sample of 863 sexually active women (age range = 20–74 years, median 44) and 103 self‐reported virgins from Busan. The presence of DNA of 34 different HPV types in cervical exfoliated cells was tested among sexually active women by means of a PCR‐based assay. IgG antibodies against L1 virus‐like particles (anti‐VLPs) of HPV types 16, 18, 31, 33 and 58 were also evaluated by means of ELISA. The overall prevalence of HPV DNA was 10.4% (95% confidence interval, CI: 8.5–12.7%). The most often found HPV DNA types were HPV 70, HPV 16 and HPV 33; 19.8% (95% CI: 17.2–22.0) of sexually active women had antibodies against one or more HPV types. The most common anti‐VLPs were against HPV 18, 31 and 16. Prevalences standardized by age on the basis of the world standard population were 13.0% for HPV DNA and 17.1% for anti‐VLPs. The concordance between the 2 HPV markers at an individual level was modest, but the risk factors for detection of HPV DNA and anti‐VLPs were similar: number of lifetime sexual partners (odds ratio, OR for ≥ 4 vs. 1 = 3.5 and 5.4, respectively), seropositivity for herpes simplex virus‐2 antibodies (OR = 2.6 and 2.5, respectively) and being single or divorced. HPV DNA, but not anti‐VLPs, were elevated among women whose husbands were thought by their wives to have extra‐marital affairs and those who had undergone vasectomy. Among 103 virgins, 4.9% had anti‐VLPs (1/73 among those aged 24 years or less). © 2002 Wiley‐Liss, Inc.
Induction of IL‐8 and monoclyte chemoattractant protein‐1 by doxorubicin in human small cell lung carcinoma cells
Authors: Shibakura Misako , Niiya Kenji , Kiguchi Toru , Kitajima Isao , Niiya Masami , Asaumi Noboru , Huh Nam‐ho , Nakata Yasunari , Harada Mine , Tanimoto Mitsune
Published: December 2002

We previously demonstrated doxorubicin‐induced urokinase expression in human H69 SCLC cells by the microarray technique using Human Cancer CHIP version 2 (Takara Shuzo, Kyoto, Japan), in which 425 human cancer‐related genes were spotted on glass plates (Kiguchi et al., Int J Cancer 2001;93:792–7). Microarray analysis also revealed significant induction of IL‐8, a member of the CXC chemokines. We have, therefore, extended the observation by testing the effects of doxorubicin on expression of the chemokine family and provide here definitive evidence that doxorubicin induces IL‐8 and MCP‐1, one of the CC chemokines, at least in 2 human SCLC cells, H69 and SBC‐1. IL‐8 antigen levels, measured by ELISA, were markedly increased in both H69 and SBC‐1 conditioned media after doxorubicin treatment, in parallel with mRNA levels; and this was dependent on the dose of doxorubicin. The ribonuclease protection assay, using a multiprobe template set for human chemokines, revealed induction of not only IL‐8 but also MCP‐1 in doxorubicin‐treated H69 cells. MCP‐1 antigen levels increased approximately 100‐fold in doxorubicin‐treated H69 cells. RT‐PCR using specific primers for MCP‐1 suggested that doxorubicin also induced MCP‐1 expression in SBC‐1 and SBC‐3 SCLC cells. Futhermore, CAT analysis using IL‐8 promoter implicated the PEA3 transcriptional factor, whose binding site was located immediately upstream of the AP‐1 and NF‐κB binding sites. Thus, it is suggested that doxorubicin induces IL‐8 and MCP‐1 chemokines in human SCLC cells by activating gene expression, in which at least PEA3 is involved. IL‐8 and MCP‐1 are major chemoattractants for neutrophils and monocytes/macrophages, respectively; therefore, extensive induction of IL‐8 and MCP‐1 may provoke the interaction between inflammatory/immune cells and tumor cells under doxorubicin stimulation and influence many aspects of tumor cell biology. © 2002 Wiley‐Liss, Inc.
Neural stem cells and neuro‐oncology: Quo vadis?
Authors: Recht Lawrence , Jang Taichang , Savarese Todd , Litofsky N.S.
Published: December 2002

Conventionally, gliomas are assumed to arise via transformation of an intraparenchymal glial cell that forms a mass that then expands centrifugally, eventually invading surrounding tissues. We propose an alternative model in which gliomas arise via initiation and promotion of cells within the brain's subependymal layer or subventricular zone, the source of a recently characterized pool of neural cells with the properties of self‐renewal and multipotentiality (i.e., stem cells) that persists into adulthood. In this model, the particular histological subtype of glioma would represent the effects of temporal and spatial environmental influences rather than the particular cell of origin and the disease's centrifugal point would be the subependymal layer. The implications of such a model are discussed. © 2002 Wiley‐Liss, Inc.
Transdifferentiation—fact or artifact
Authors: Liu Ying , Rao Mahendra S.
Published: December 2002

Normal development appears to involve a progressive restriction in developmental potential. However, recent evidence suggests that this progressive restriction is not irreversible and can be altered to reveal novel phenotypic potentials of stem, progenitor, and even differentiated cells. While some of these results can be explained by the presence of contaminating cell populations, persistence of pluripotent stem cells, cell fusion, etc., several examples exist that are difficult to explain as anything other than “true transdifferentiation” and/or dedifferentiation. These examples of transdifferentiation are best explained by understanding how the normal process of progressive cell fate restriction occurs during development. We suggest that subversion of epigenetic controls regulating cell type specific gene expression likely underlies the process of transdifferentiation and it may be possible to identify specific factors to control the transdifferentiation process. We predict, however, that transdifferentiation will not be reliable or reproducible and will probably require complex manipulations. Published 2002 Wiley‐Liss, Inc.
A Model for mechanotransduction in bone cells: The load‐bearing mechanosomes
Authors: Pavalko Fred M. , Norvell Suzanne M. , Burr David B. , Turner Charles H. , Duncan Randall L. , Bidwell Joseph P.
Published: December 2002

The skeleton's response to mechanical force, or load, has significance to space travel, the treatment of osteoporosis, and orthodontic appliances. How bone senses and processes load remains largely unknown. The cellular basis of mechanotransduction, however, likely involves the integration of diffusion‐controlled signaling pathways with a solid‐state scaffold linking the cell membrane to the genes. Here, we integrate various concepts from models of connective membrane skeleton proteins, cellular tensegrity, and nuclear matrix architectural transcription factors, to describe how a load‐induced deformation of bone activates a change in the skeletal genetic program. We propose that mechanical information is relayed from the bone to the gene in part by a succession of deformations, changes in conformations, and translocations. The load‐induced deformation of bone is converted into the deformation of the sensor cell membrane. This, in turn, drives conformational changes in membrane proteins of which some are linked to a solid‐state signaling scaffold that releases protein complexes capable of carrying mechanical information, “mechanosomes”, into the nucleus. These mechanosomes translate this information into changes in the geometry of the 5′ regulatory region of target gene DNA altering gene activity; bending bone ultimately bends genes. We identify specific candidate proteins fitting the profile of load‐signaling mechanosomes. © 2002 Wiley‐Liss, Inc.
Somatic plasticity of neural stem cells: Fact or fancy?
Authors: Greco Beatrice , Recht Lawrence
Published: December 2002

Several studies have described the potential for embryonic and adult neural stem cells to differentiate into non‐neural cells such as muscle and blood, tissues that are derived from non‐neuroectodermal germ layers. This raised the exciting possibility that these cells possessed a broader range of differentiation potential than originally thought and raised interesting prospects for possible transplantation utilization. However, a number of recent reports have raised questions about whether the phenomena observed actually represented true somatic plasticity. In this review, we critically analyze these studies with the aim of providing some criteria by which future studies that address this important problem may be evaluated. © 2002 Wiley‐Liss, Inc.
Induction of senescence‐associated growth inhibitors in the tumor‐suppressive function of retinoids
Authors: Roninson Igor B. , Dokmanovic Milos
Published: December 2002

Retinoids, physiological regulators of cell growth and differentiation, are used in the treatment or chemoprevention of several malignant diseases. This class of compounds can induce growth arrest or apoptosis in tumor cells. Permanent growth arrest of retinoid‐treated cells is often assumed to result from retinoid‐induced differentiation. Recent studies in breast carcinoma and neuroblastoma cells demonstrated that retinoids can stop tumor cell growth through the program of senescence rather than differentiation. Retinoid‐induced tumor suppression is associated with the induction of multiple intracellular and secreted growth‐inhibitory proteins. Most of these proteins were also found to be upregulated in senescent cells. The induction of senescence‐associated growth inhibitors appears to be an indirect effect of retinoids. Elucidation of the mechanisms responsible for the induction of growth‐inhibitory genes in retinoid‐treated cells should help in developing agents that would mimic the antiproliferative effect of retinoids in retinoid‐insensitive cancers. © 2002 Wiley‐Liss, Inc.
Retinal neuroprotection by growth factors: A mechanistic perspective
Authors: Chaum Edward
Published: December 2002

For more than a decade it has been known that certain growth factors inhibit apoptosis in genetically determined and experimental models of inner and outer retinal degeneration. The molecular mechanisms underlying these protective effects and the signaling that supports the survival of photoreceptors and retinal ganglion cells in these models have recently come under more in depth investigation. This paper reviews our current understanding of the balance of pro‐ and antiapoptotic signals that determine cell fate in the retina and how the activation of key signal transduction pathways by specific classes of neurotrophins protects retinal neurons. © 2002 Wiley‐Liss, Inc.
Induction of p202, a modulator of apoptosis, during oncogenic transformation of NIH 3T3 cells by activated H‐Ras (Q61L) contributes to cell survival
Authors: Xin Hong , Geng Yanbiao , Pramanik Rocky , Choubey Divaker
Published: December 2002

Previous studies have revealed that p202 (52 kDa), an interferon (IFN) and differentiation‐inducible protein, negatively regulates cell proliferation and modulates cell survival. However, the role of p202 in transformed cells remains to be investigated. Here we report that constitutive expression of oncogenic H‐Ras (Q61L) in NIH 3T3 cells, which resulted in cell transformation, was associated with increases in the steady‐state levels of 202 RNA and protein. Interestingly, the increase in p202 levels in transformed cells correlated with increases in the activity of the transcription factor c‐Jun/AP‐1, which bound to the two potential AP‐1 DNA binding sites (the AP‐1CS1 and AP‐1CS2) in the 5′‐regulatory region of the 202 gene in gel mobility shift assays. Furthermore, the site‐directed mutagenesis, coupled with promoter‐reporter analyses, revealed that these two AP‐1 DNA binding sites contribute to the regulation of the 202 gene in Ras transformed cells. Because treatment of transformed cells with a specific inhibitor of MEK (PD 98059) resulted in significant decreases in the levels of p202, these observations raise the possibility that in transformed cells Ras/Raf/MEK pathway regulates the transcriptional activation of the 202 gene. Significantly, decreases in the levels of p202 in Ras transformed NIH 3T3 cells under reduced serum conditions increased the susceptibility to apoptosis. Collectively, our observations support the idea that the transcriptional increases in the levels of p202 by oncogenic H‐Ras in NIH 3T3 cells are needed for cell survival. © 2002 Wiley‐Liss, Inc.
Microsatellite DNA analyses support an east‐west phylogeographic split of American alligator populations
Authors: Davis Lisa M. , Glenn Travis C. , Strickland Denise C. , Guillette Louis J. , Elsey Ruth M. , Rhodes Walter E. , Dessauer Herbert C. , Sawyer Roger H.
Published: December 2002

We examined the population genetic structure of American alligators (Alligator mississippiensis) sampled from 12 localities across the southeastern United States. The primary goal of this study was to determine the extent of population differentiation among alligators from four Florida lakes using eight microsatellite loci and compare the results to additional sites located at varying distances from them. Analyses of population structure revealed little differentiation (FST=0.039; Rho=0.012) among the four Florida lakes, Apopka, Griffin, Orange and Woodruff, which are all located in the St. John&'s River watershed in north‐central Florida. Further, there was little differentiation among these samples and samples collected from the Everglades National Park (FST=0.044; Rho=0.009) and south Georgia (FST=0.045; Rho=0.032). Therefore, these six samples were pooled together as a “FL/sGA group.” Similarly, samples collected in the western extent of the range, Anahuac National Wildlife Refuge in Texas and Salvador Wildlife Management Area, Marsh Island Wildlife Refuge and Rockefeller Wildlife Refuge in Louisiana, also lacked population structure (FST=0.024; RST=0.040). These four populations were pooled into the “TX/LA group.” Comparisons of these two groups with samples taken from the Santee Coastal Reserve in South Carolina and Mobile, Alabama yielded three to four times more differentiation among groups (FST=0.131; Rho=0.187). These and other analyses support the hypothesis of an east‐west phylogeographic split in American alligator populations and are consistent with studies of many freshwater fish and aquatic and terrestrial turtles distributed throughout this same geographic region. J. Exp. Zool. (Mol. Dev. Evol.) 294:352–372, 2002. © 2002 Wiley‐Liss, Inc.
Serum procalcitonin concentrations in bacterial pneumonia in children: A negative result in primary healthcare settings
Authors: Korppi Matti , Remes Sami , Heiskanen‐Kosma Tarja
Published: December 2002

A microbe‐specific diagnosis in community‐acquired pneumonia (CAP) is difficult in children, and studies on nonspecific chest radiographic and host response markers have been inconsistent. Serum procalcitonin (PCT) is a newly recognized, promising marker for differentiating between bacterial and viral infections. Serum PCT was measured by a luminometric assay in 190 children with CAP diagnosed in the primary healthcare setting during a population‐based study in a geographically defined population. The pneumococcal, mycoplasma, chlamydia, and viral etiology of infections was studied by an extensive serologic test panel.

The median PCT concentrations were 0.47, 0.46, and 0.35 ng/mL in children aged <5 years, 5–9 years, and ≥10 years (P = 0.004). An elevated PCT >1.0 ng/mL was seen in 12.1% and >2.0 ng/mL in only 2.1% of the children. No association was seen between severity (inpatient vs. outpatient care) and etiology of CAP (evidence for pneumococcal, mycoplasma, or chlamydia, vs. viral infection).

We conclude that serum PCT measurements have no role in the diagnosis of bacterial CAP in children in primary healthcare settings. Pediatr Pulmonol. 2003; 35:56–61. © 2003 Wiley‐Liss, Inc.
Influence of maturation on infant diaphragm function assessed by magnetic stimulation of phrenic nerves
Authors: Dimitriou Gabriel , Greenough Anne , Moxham John , Rafferty Gerrard F.
Published: December 2002

Infant diaphragm function may be adversely affected in a variety of disorders and conditions. Key to establishing an accurate diagnosis are appropriate control data. The aim of this study was to determine the effect of maturation on diaphragm function, using a nonvolitional test. Diaphragm function was assessed by measuring the transdiaphragmatic pressure (Pdi) generated by magnetic stimulation of the phrenic nerves. Ballon catheters were positioned in the lower third of the esophagus and stomach. Esophageal (Pes) and gastric (Pgas) pressure changes were measured using differential pressure transducers. The pressure signals were amplified and displayed in real time on a computer (running Labview™ software) and Pdi derived by online subtraction of Pes from Pgas.

Twenty‐nine infants (14 born preterm), at a median gestational age of 37 (range, 25–42) weeks, were studied at a median postconceptional age (PCA) of 39 (range, 32–44) weeks. At time of measurement, none had respiratory problems or were hyperinflated (functional residual capacity ranged from 23–35 mL/kg). The preterm infants had significantly lower transdiaphragmatic pressures responses following median left (4.0, range 2.5–6.8 cmH2O vs. 4.8, range 2.8–7.2 cmH2O) and median right phrenic nerve stimulation (3.6, range 2.6–4.8 cmH2O vs. 4.3, range 2.7–6.8 cmH2O) (P < 0.05) than term infants. Following left and right phrenic nerve stimulation, Pdi correlated significantly with gestational age (r = 0.4, P < 0.05, and r = 0.4, P < 0.05, respectively) and PCA (r = 0.37, P = 0.05, and r = 0.56, P < 0.01, respectively).

We conclude that gestational age at birth and postconceptional age at time of measurements must be taken into account when interpreting the results of infant diaphragm function tests. Pediatr Pulmonol. 2003; 35:17–22. © 2003 Wiley‐Liss, Inc.
Lung function and symptom perception in children with asthma and their parents
Authors: Horak Elisabeth , Grässl Gerhard , Skladal Daniela , Ulmer Hanno
Published: December 2002

A large proportion of children with asthma are managed without recourse to specialized care, and treatment decisions are based solely on symptoms as reported by the children and their parents. We investigated 90 school‐age children with the diagnosis of asthma and their accompanying parent to evaluate whether we can obtain better information by using three different means of asking for asthma symptoms: a questionnaire for children (QSRchildren), “smilies,” and a visual analogue scale for children (VASchildren). Furthermore, we analyzed the relationship between these symptom reports and lung function results. Finally, we attempted to determine whether performing a lung function test contributes relevant information toward improving asthma management.

Multiple linear regression adjusted for age and gender showed a significant relationship between VAS for children and forced expiratory volume in 1 sec (FEV1) (P = 0.047) and maximal expiratory flow at 50% of forced vital capacity (MEF50) (P = 0.037). Neither age, gender, QSR for children, “smilies for children” nor all the parents' scores showed a significant association with lung function measurement in the regression model. Subgroup analysis with Spearman's rank correlation coefficients by age group revealed significant correlation in children <10 years between VAS for children, QSR for parents, smilies for parents, and the lung function parameters FEV1, and MEF50. Above age 10 years there was no correlation at all, with the accuracy correlation ranging from −0.04 to +0.21.

Our data demonstrate that reported symptoms do not reliably correlate with lung function results in asthmatic children and the childrens' parents, and correlation is dependent on the instrument used for symptom evaluation. In children, the VAS, and in parents, the QSR were the most valuable means of obtaining best information on asthma symptoms. This underlines the importance of supplementing information on asthma symptoms with lung function measurements to more reliably assess the severity of asthma. Pediatr Pulmonol. 2003; 35:23–28. © 2003 Wiley‐Liss, Inc.
Thrombin contributes to bronchoalveolar lavage fluid mitogenicity in lung disease of the premature infant
Authors: Dik Willem A. , Zimmermann Luc J.I. , Naber Brigitta A. , Janssen Daphne J. , van Kaam Anton H.L.C. , Versnel Marjan A.
Published: December 2002

Chronic lung disease of prematurity (CLD) is a common consequence of neonatal respiratory distress syndrome (RDS) and is characterized by pulmonary fibrosis. Increased thrombin activity in the alveolar compartment is associated with pulmonary fibrosis in adults and animals, and contributes to bronchoalveolar lavage (BAL) fluid mitogenicity for fibroblasts. We hypothesized that BAL fluid from infants who develop CLD contains increased mitogenic activity for lung fibroblasts compared to BAL fluid from resolving RDS, and that increased thrombin levels contribute to this activity. Sequential BAL (postnatal days 2–14) was obtained from 37 premature infants who were ventilated for RDS. Twenty‐six infants developed CLD, whereas 11 resolved. BAL fluid mitogenic activity was determined in a proliferation assay, using human fetal lung fibroblasts. The contribution of thrombin to mitogenic activity was determined using the thrombin inhibitor PPACK. Furthermore, thrombin levels in BAL fluid were measured using a specific substrate to detect thrombin activity and by measuring thrombin‐antithrombin III complex (TATIII). BAL fluid mitogenic activity was comparable between CLD and RDS (CLD, 33% proliferation on day 2 to 41% on day 14; RDS, 21% on day 2 to 54% on day 7). Thrombin inactivation by PPACK completely inhibited mitogenic activity in BAL samples obtained on days 2 and 4 (CLD, P < 0.001 on days 2 and 4; RDS, P < 0.05 on day 4). From day 7 onwards, inhibition of thrombin only partly reduced (P < 0.05) CLD BAL fluid mitogenic activity, indicating that other mitogenic factors contribute as well. Suprisingly, thrombin activity and TATIII were decreased in BAL fluid from CLD compared with RDS patients on days 2 and 4. In conclusion, our study shows that BAL fluid from infants with and without CLD development is equally mitogenic for lung fibroblasts, and that thrombin is a major mitogen in these samples. This suggests that fibroproliferation may occur early in the lungs from infants with both CLD and RDS, and that thrombin contributes to this. Pediatr Pulmonol. 2003; 35:34–41. © 2003 Wiley‐Liss, Inc.
Method for assessment of volume of trapped gas in infants during multiple‐breath inert gas washout
Authors: Gustafsson Per M. , Källman Sigun , Ljungberg Henrik , Lindblad Anders
Published: December 2002

A breath‐by‐breath inert gas washout method for assessment of the volume of trapped gas in the lungs (VTG) in sedated sleeping infants is described. It is based on washin using a gas mixture containing 4% sulfur hexafluoride (VTG,SF6) and washout with air. A mass spectrometer was used for continuous gas concentration measurements, and a Fleisch no. 0 pneumotachometer for flow measurement. When equilibration of the tracer gas was achieved with tidal breathing washin, five passive inflations with a maximum positive airway pressure of 20 cm of H2O were performed to ensure filling of lung spaces not communicating during tidal breathing. After tidal washout of the tracer gas by air until the end‐tidal concentration was 1/40th of its starting concentration, five passive inflations with air were instituted again. The VTG,SF6 was calculated from the volume of SF6 mobilized by these large breaths, and expressed as the corresponding volume of air.

Triplets of VTG,SF6 determination in 8 infants aged 9–31 months with varying degrees of airway obstruction showed an average volume of 13.7 mL (range, 4.7–25.0). The average SD of the triplets was 2.1 mL (range, 0.1–5.5 mL). Subjects with high VTG,SF6/FRC results demonstrated lower maximal expiratory flow at FRC (V′maxFRC) results (Z‐scores) and greater inhomogeneity of ventilation distribution than those with low trapped gas volumes.

It is concluded that gas trapping can be assessed with acceptable precision with this washout method. Further studies are needed to establish the sensitivity and usefulness of the method in infants with various types of airway pathology. Pediatr Pulmonol. 2003; 35:42–49. © 2003 Wiley‐Liss, Inc.
Nitrotyrosine and NO synthases in infants with respiratory failure: Influence of inhaled NO
Authors: Aikio Outi , Vuopala Katri , Pokela Marja‐Leena , Andersson Sture , Hallman Mikko
Published: December 2002

Inhaled nitric oxide (NO) is a selective vasodilator in pulmonary hypertension. However, the safety of inhaled NO (iNO) has not been established. Using an immunohistochemical technique, we studied the expression of NO synthase (NOS) isoforms NOS1, NOS2, NOS3, and nitrotyrosine, the marker of toxic NO‐superoxide pathway, in lung specimens from autopsies.

Twelve infants dying with respiratory failure had iNO up to 60 parts per million for 0.1–15 days. Twelve control infants were matched in pairs on the basis of the diagnosis, number of gestational days at birth, age at death, and whether extracorporeal perfusion was required. In addition, 5 infants who died of SIDS or nonpulmonary trauma (healthy lungs) were compared to 8 age‐matched cases with respiratory failure. Immunostaining was graded by the intensity of the color deposit and the frequency in specific cells stained.

Inhaled NO tended to increase NOS2 expression in bronchiolar epithelium and adjacent tissue. There were no other differences in the distribution of nitrotyrosine or NOS isoforms between iNO‐treated infants and the control group with respiratory failure. All NOS isoforms were evident in the lungs studied. In severe respiratory failure, nitrotyrosine was mostly detectable in the bronchiolar epithelium and alveolar exudates, whereas in healthy lungs those sites did not contain nitrotyrosine.

The alveolar tissue of infants with progressive respiratory may be affected by the NO‐superoxide pathway. However, inhalation of NO was not associated with a detectable increase in oxidant stress. Pediatr Pulmonol. 2003; 35:8–16. © 2003 Wiley‐Liss, Inc.
Calcium binding to the transmembrane domain of the sarcoplasmic reticulum Ca2+‐ATPase: Insights from molecular modeling
Authors: Costa Valeria , Carloni Paolo
Published: December 2002

Sarcoplasmic reticulum Ca2+‐ ATPase pumps Ca2+ ions from muscle cells to the sarcoplasmic reticulum. Here we use molecular dynamics and electrostatic modeling to investigate structural and dynamical features of key intermediates in the Ca2+ binding process of the protein. Structural models of the protein (containing either two, one, or no calcium ions in the transmembrane domain) are constructed based on the X‐ray structure by Toyoshima et al. (Nature 2000;405:647–655). The protein is embedded in a water/octane bilayer, which mimics the water/membrane environment. Our calculations provide information on the hydration of the two Ca2+ ions, not emerging from the X‐ray structure. Furthermore, they indicate that uptake of the metal ions causes large structural rearrangements of the metal binding sites. In addition, they suggest that the two ions reach their binding sites via two specific pathways. Finally, they allow identification of residues in the outer mouth of the protein that might interact with the Ca2+ ions during the binding process. Proteins 2003;50:104–113. © 2002 Wiley‐Liss, Inc.
Protein‐based virtual screening of chemical databases. II. Are homology models of g‐protein coupled receptors suitable targets?
Authors: Bissantz Caterina , Bernard Philippe , Hibert Marcel , Rognan Didier
Published: December 2002

The aim of the current study is to investigate whether homology models of G‐Protein‐Coupled Receptors (GPCRs) that are based on bovine rhodopsin are reliable enough to be used for virtual screening of chemical databases. Starting from the recently described 2.8 Å‐resolution X‐ray structure of bovine rhodopsin, homology models of an “antagonist‐bound” form of three human GPCRs (dopamine D3 receptor, muscarinic M1 receptor, vasopressin V1a receptor) were constructed. The homology models were used to screen three‐dimensional databases using three different docking programs (Dock, FlexX, Gold) in combination with seven scoring functions (ChemScore, Dock, FlexX, Fresno, Gold, Pmf, Score). Rhodopsin‐based homology models turned out to be suitable, indeed, for virtual screening since known antagonists seeded in the test databases could be distinguished from randomly chosen molecules. However, such models are not accurate enough for retrieving known agonists. To generate receptor models better suited for agonist screening, we developed a new knowledge‐ and pharmacophore‐based modeling procedure that might partly simulate the conformational changes occurring in the active site during receptor activation. Receptor coordinates generated by this new procedure are now suitable for agonist screening. We thus propose two alternative strategies for the virtual screening of GPCR ligands, relying on a different set of receptor coordinates (antagonist‐bound and agonist‐bound states). Proteins 2003;50:5–25. © 2002 Wiley‐Liss, Inc.
Efficient RMSD measures for the comparison of two molecular ensembles
Authors: Brüschweiler Rafael
Published: December 2002

Quantitative measures are presented for comparing the conformations of two molecular ensembles. The measures are based on Kabsch's formula for the root‐mean‐square deviation (RMSD) and the covariance matrix of atomic positions of isotropically distributed ensembles (IDE). By using a Taylor series expansion, it is shown that the RMSD can be expressed solely in terms of the IDE matrices. A fast approximate method is introduced for the pairwise RMSD determination whose computational cost scales linearly with the number of structures. A similarity measure for two structural ensembles that is based on the trace metric of the differences of powers of the IDE matrices is presented. The measures are illustrated for conformational ensembles generated by a molecular dynamics computer simulation of a partially folded A‐state analog of ubiquitin. Proteins 2003;50:26–34. © 2002 Wiley‐Liss, Inc.
Subcellular location prediction of apoptosis proteins
Authors: Zhou Guo‐Ping , Doctor Kutbuddin
Published: December 2002

Apoptosis proteins have a central role in the development and homeostasis of an organism. These proteins are very important for understanding the mechanism of programmed cell death. Many efforts in pharmaceutical research have been aimed at understanding their structure and function. Unfortunately, thus far, very few apoptosis protein structures have been determined. In contrast, many apoptosis protein sequences are known, and many more are expected to come in the near future. Because of the extremely unbalanced state, it would be worthwhile to develop a fast sequence‐based method to identify their subcellular location so as to gain some insight about their biological function. In view of this, a study was initiated in an attempt to identify the subcellular location of apoptosis proteins according to their sequences by means of the covariant discriminant function, which was established based on the Mahalanobis distance and Chou's invariance theorem (Chou, Proteins 1995;21:319–344). The results were quite promising, indicating that the subcellular location of apoptosis proteins are predictable to a considerably accurate extent if a good training data set can be established. It is expected that, with a continuous improvement of the training data set by incorporating more and more new data, the current method might eventually become a useful tool in this area because the function of an apoptosis protein is closely related to its subcellular location. Proteins 2003;50:44–48. © 2002 Wiley‐Liss, Inc.
Role of the protein side‐chain fluctuations on the strength of pair‐wise electrostatic interactions: Comparing experimental with computed pKas
Authors: Alexov Emil
Published: December 2002

The effect of the protein side‐chain fluctuations on the strength of electrostatic interactions was studied. The effect was modeled on 7 different crystal structures on the same enzyme as well as on 20 molecular dynamics snapshot structures. It was shown that the side‐chain flexibility affects predominantly the magnitude of the strong pair‐wise interactions, that is, the pair‐wise interaction among ion pairs, and practically does not affect the interactions with the rest of the protein. This was used to suggest a correction function that should be applied to the original pair‐wise electrostatic interaction to mimic the effects of the fluctuations. The procedure is applied on three ion pairs identified in lysozyme. It was shown that sampling different side‐chain rotamers and modifying the strength of the pair‐wise interaction energies makes calculated pKas less sensitive to the fluctuations of the structure and improves the prediction accuracy. Proteins 2003;50:94–103. © 2002 Wiley‐Liss, Inc.
Analysis of the binding energies of testosterone, 5α‐dihydrotestosterone, androstenedione and dehydroepiandrosterone sulfate with an antitestosterone antibody
Authors: Nordman Nana , Valjakka Jarkko , Peräkylä Mikael
Published: December 2002

Molecular dynamics simulations and molecular mechanics–Poisson–Boltzmann surface area (MM‐PBSA) free energy calculations were used to study the binding of testosterone (TES), 5α‐dihydrotestosterone (5ADHT), androstenedione (AND), and dehydroepiandrosterone sulfate (DHEAS) to the monoclonal antitestosterone antibody 3‐C4F5. The relative binding free energy of TES and AND was also calculated with free energy perturbation (FEP) simulations. The antibody 3‐C4F5 has a relatively high affinity (3 × 108 M−1) and on overall good binding profile for testosterone but its cross‐reactivity with DHEAS has been the main reason for the failure to use this antibody in clinical immunoassays. The relative binding free energies obtained with the MM‐PBSA method were 1.5 kcal/mol for 5ADHT, 3.8 kcal/mol for AND, and 4.3 kcal/mol for DHEAS, as compared to TES. When a water molecule of the ligand binding site, observed in the antibody–TES crystal structure, was explicitly included in MM‐PBSA calculations, the relative binding energies were 3.4, 4.9, and 5.4 kcal/mol for 5ADHT, AND, and DHEAS, respectively. The calculated numbers are in correct order but larger than the corresponding experimental energies of 1.3, 1.5, and 2.6 kcal/mol, respectively. The fact that the MM‐PBSA method reproduced the relative binding free energies of DHEAS, a steroid having a negatively charged sulfate group, and the neutrally charged TES, 5ADHT, and AND in satisfactory agreement with experiment shows the robustness of the method in predicting relative binding affinities. The 800‐ps FEP simulations predicted that the antibody 3‐C4F5 binds TES 1.3 kcal/mol tighter than AND. Computational mutagenesis of selected amino acid residues of the ligand binding site revealed that the lower affinities of AND and DHEAS as compared to TES are due to a combined effect of several residues, each contributing a small fraction to the tighter binding of TES. An exception to this is Tyr99H, whose mutation to Ala lowered the binding of DHEAS 0.7 kcal/mol more than the binding of TES. This is probably due to the hydrogen bonding interaction formed between the OH group of Tyr99H and the sulfate group of DHEAS. Computational mutagensis data also showed that the affinity of the steroids to the antitestosterone antibody 3‐C4F5 would be enhanced if Trp47H were repositioned so that it would make more extensive contacts with the bound ligands. In addition, the binding of steroids to antitestosterone, antiprogesterone, and antiestradiol antibodies is discussed. Proteins 2003;50:135–143. © 2002 Wiley‐Liss, Inc.