bluuebunny/crossref_metadata_2025 huggingface dataset:
Transgenic mice engineered to target Cre/loxP‐mediated DNA recombination into catecholaminergic neurons
Authors: Gelman Diego M. , Noaín Daniela , Avale M. Elena , Otero Verónica , Low Malcolm J. , Rubinstein Marcelo
Published: August 2003

Summary: To introduce restricted DNA recombination events into catecholaminergic neurons using the Cre/loxP technology, we generated transgenic mice carrying the Cre recombinase gene driven by a 9 kb rat tyrosine hydroxylase (TH) promoter. Immunohistochemistry performed on transgenic mouse brain sections revealed a high number of cells expressing Cre in areas where TH is normally expressed, including the olfactory bulb, hypothalamic and midbrain dopaminergic neurons, and the locus coeruleus. Double immunohistochemistry and immunofluorescence indicated that colocalization of TH and Cre is greater than 80%. Cre expression was also found in TH‐positive amacrine neurons of the retina, chromaffin cells of the adrenal medulla, and sympathetic ganglia. We intercrossed TH‐Cre mice with the floxed reporter strain Z/AP and observed efficient Cre‐mediated recombination in all areas expressing TH, indicating that transgenic Cre is functional. Therefore, we have generated a valuable transgenic mouse strain to induce specific mutations of “floxed” genes in catecholaminergic neurons. genesis 36:196–202, 2003. © 2003 Wiley‐Liss, Inc.
Differentiation and diversification of the follicular cells in flies: Insight from the studies of the lower brachycerans' ovaries
Authors: Kubrakiewicz Janusz , Jabłońska Anna , Mazurkiewicz Marta , Biliński Szczepan M.
Published: August 2003

Summary: Although all dipteran species have ovaries of the same meroistic‐polytrophic type, the structure of individual ovarian follicles (egg chambers) as well as the course of oogenesis in major dipteran taxa are highly diversified and often significantly different from the widely known Drosophila model. In this report we present results of the morphological studies of the ovary structure in the representatives of three families of lower brachycerans (Orthorrhapha) and compare them with the present knowledge of the processes that lead to the formation of a mature egg cell in the model dipteran, the cyclorrhaphan fruit fly, Drosophila melanogaster. The most conspicuous and developmentally significant differences between Drosophila and lower brachycerans were found in the events that accompany the differentiation and diversification of somatic follicular cells. Our observations indicate that the directed migrations of some follicular cells within the egg chamber and the ability of border cells to invade the nurse cell compartment can be considered as evolutionary novelties that evolved in the ancestors of higher brachycerans. genesis 36:214–224, 2003. © 2003 Wiley‐Liss, Inc.
Patients and families desire a patient to be told the diagnosis of dementia: a survey by questionnaire on a Dutch memory clinic
Authors: Dautzenberg Paul L. J. , van Marum Rob J. , van der Hammen Roger , Paling Heleen A.
Published: August 2003

Background

Controversy exists as to whether dementia patients should be told their diagnosis.

Objective

This study examined as to whether, both patients with subdued memory impairment and their accompanying relatives want a diagnosis of dementia or somatic disease disclosed to the referred patient.

Method

Fifty consecutive out‐patients referred to a memory clinic and their accompanying relatives filled in a questionnaire regarding their views on telling the diagnosis to the patient in case of a somatic disease and in case of a dementia. An ordinal scoring system was used (not important 1; little important 2; important 3 and very important 4).

Results

Forty‐six (92%) questionnaires were completed. All the patients and their accompanying relatives thought it was at least important that physicians should tell the patient their diagnosis in case of a somatic disease, and 96% of the patients, 100% of the spouse and 94% of the non‐spouse accompanying relatives stated the same in case of a dementia. All the spouses and most of the accompanying relatives showed similar desires for a dementia or somatic diagnosis.

Conclusion

In The Netherlands, out‐patients with subdued memory impairment, mostly suffering from a dementing illness, wish to be informed of their diagnosis, therefore should not automatically be considered incompetent. Copyright © 2003 John Wiley & Sons, Ltd.
The role of individual, interpersonal, and organizational factors in mitigating burnout among elderly Chinese volunteers
Authors: Yan Elsie Chau‐wai , Tang Catherine So‐kum
Published: August 2003

Objective

This study examined the role of individual, interpersonal, and organizational factors in mitigating burnout among elderly Chinese volunteers in Hong Kong.

Methods

A total of 295 elderly Chinese volunteers were individually interviewed on their demographic characteristics, voluntary service experience, physical health status, general self‐efficacy, social support, satisfaction and perceived benefit from volunteer work, and burnout symptoms. Exploratory factor analysis was first performed to determine the underlying dimensions of burnout experience. Correlation analyses were then conducted to explore associations among major variables. Hierarchical regression analyses were also performed to unearth the relative contribution of various factors in predicting burnout among elderly volunteers.

Results

A two‐factor structure of burnout, namely lack of personal accomplishment and emotional depletion, was found. Demographics, individual, interpersonal, and organizational factors were significant predictors of lack of personal accomplishment. In particular, personal accomplishment was best predicted by a long duration of voluntary work service and high levels of self‐efficacy, work satisfaction, and perceived benefit. For emotional depletion, only demographics and individual factors were significant predictors. A low level of emotional depletion was best predicted by older age, a short duration of voluntary work experience, and good health.

Conclusions

Burnout experience was evident among elderly Chinese volunteers. There were different predictors of affective and cognitive components of burnout. Findings have significant implications to attenuate burnout symptoms among elderly volunteers. Copyright © 2003 John Wiley & Sons, Ltd.
The needs of older people with mental health problems according to the user, the carer, and the staff
Authors: Hancock Geraldine A. , Reynolds Tom , Woods Bob , Thornicroft Graham , Orrell Martin
Published: August 2003

Background

Individual assessment of needs has been recognised as the most appropriate way to allocate health and social care resources. These assessments, however, are often made by the staff or by a carer who acts as an advocate for the user themselves. Little is known about how these proxy measures compare to how individual patients perceive their own needs.

Aim

The aim of this study was to measure and compare ratings of need for older people with mental health problems by the older person themselves, their carer, and an appropriate staff member.

Method

One‐hundred and one older people were identified from various mental health services and 87 users, 57 carers, and 95 staff were interviewed using the Camberwell Assessment of Need for the Elderly (CANE) to identify met and unmet needs.

Results

Users identified significantly fewer of their needs (5.5) than either staff (8.1) or carers (8.3) did, but this difference was accounted for by people with dementia reporting less needs. Users identified fewer psychological or social needs (e.g. daytime activities, company, or carer distress) than staff or carers did. The average Kappa indicating level of agreement between staff and user was 0.52, between user and carer was 0.53, and between carer and user was 0.58. This showed only a fair level of reliability between different ratings of need.

Conclusions

User perspectives should be given a high priority when assessing individual needs. Fears that assessment of need would be unduly time‐consuming or would simply reflect individual demands should be allayed. A user‐based assessment will assist healthcare providers to prioritise needs according to what the user themselves consider to be most important, beneficial, and acceptable to them. Reliance solely on assessment by staff or carers may not lead to the most equitable or appropriate use of services. Copyright © 2003 John Wiley & Sons, Ltd.
The neglect of somatoform disorders by old age psychiatry: some explanations and suggestions for future research
Authors: Wijeratne Chanaka , Brodaty Henry , Hickie Ian
Published: August 2003

Aim

The somatoform disorders have long been ignored by old age psychiatry. The main aim of this paper is to identify and examine possible reasons for this neglect.

Method

A selective review of the general literature on somatoform disorders.

Results

Significant conceptual, diagnostic and classificatory problems have impeded the consideration of somatoform disorders in older people. There is a perception that somatoform disorders are infrequent and have not been validated as independent clinical disorders. However, we present evidence that the more broadly defined somatoform disorders are common in all age groups in primary care and meet criteria for the determination of clinical validity. General difficulties in the assessment of psychiatric disorders in primary care, the setting in which somatoform disorders are most common, are compounded by a lack of support from old age psychiatry services. Effective psychological therapies may not be readily available to sufferers.

Conclusion

There is a need for change in the conceptualisation and nosology of the somatoform disorders. The formulation of age appropriate diagnostic criteria and presentations is a prerequisite for determining the clinical validity of these disorders in older people. This can be followed by study of their frequency, associated risk factors and treatment. A system of education that enhances the management of these disorders within primary care and old age psychiatry services is needed. Copyright © 2003 John Wiley & Sons, Ltd.
Comparative effects of risperidone and olanzapine on cognition in elderly patients with schizophrenia or schizoaffective disorder
Authors: Harvey Philip D. , Napolitano Judy A. , Mao Lian , Gharabawi Georges
Published: August 2003

Objective

To examine the effects of risperidone and olanzapine on cognitive functioning in elderly patients with schizophrenia or schizoaffective disorder.

Method

One hundred seventy‐six elderly inpatients and outpatients with schizophrenia or schizoaffective disorder were enrolled in this multicenter, double‐blind trial. After their antipsychotic medications were tapered for 1 week, patients were randomly assigned to receive either risperidone 1 to 3 mg/day or olanzapine 5 to 20 mg/day for 8 weeks. Performance on the Continuous Performance Test (CPT), Serial Verbal Learning Test (SVLT), TMT (Trail Making Test) Parts A and B, Wisconsin Card Sorting Test (WCST), and Verbal Fluency Examinations (VFE) was assessed at baseline and at end point.

Results

Patients in the risperidone group had improved scores on at least one test of attention, memory, executive function, and verbal fluency, and those in the olanzapine group had improved scores on at least one test of attention and memory function. Scores on the TMT Part B, WCST total errors (executive function domain), and the VFE improved significantly from baseline in the risperidone group but not in the olanzapine group. No significant differences in change scores between the two groups were found. Higher baseline scores on each test predicted more improvement at endpoint.

Conclusions

Low doses of risperidone and olanzapine improve cognitive function in elderly patients with schizophrenia or schizoaffective disorder. Consistent with research in younger populations, these improvements occur in aspects of cognitive functioning related to functional outcome. Copyright © 2003 John Wiley & Sons, Ltd.
Heat transfer control in an enclosure by using a rotating plate and stratified fluids
Authors: Kimura Teruo , Takeuchi Masanori , Nagai Niroh , Yoshida Tetsuya
Published: August 2003

The effects of an inner rotating plate with horizontal axis on the heat transfer between two vertical walls in a rectangular enclosure with stratified fluid layers were investigated experimentally. The aspect ratio of the enclosure height/width was 1 throughout the experiments. An acrylic plate with small thermal conductivity was installed horizontally at the center of the square enclosure, and was rotated at various speeds for normal and reverse rotations by using the motor installed outside of the enclosure. Purified water and silicon oil were used as the working fluids and were stratified in the enclosure. It is shown here that the heat transfer rate of the enclosure with stratified fluid layers differs largely from that of the enclosure with a single fluid layer. Namely, the heat transfer coefficient increases rapidly at a low rotating speed range, and maintains an almost constant value at a high rotating speed range. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(6): 489–500, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10081
Thermal imaging system applying two‐color thermometry
Authors: Yamada Jun , Murase Toru , Kurosaki Yasuo
Published: August 2003

This study proposes a new thermal imaging system using the principle of two‐color thermometry to determine the temperature of objects. The system can provide a thermal image of objects without being assigned their emissivity. Applying two‐color thermometry to a thermograph is performed by dividing the detectable wavelength range of a radiation detector into two different ranges using respective bandpass filters. A thermal image is constructed from the two energy distributions of radiation which are measured after passing through each filter. In this study, in order to evaluate the accuracy of imaged temperature in the present system, an error analysis for imaged temperature is carried out and the accuracy of the imaged temperature in the present system is compared with those in a conventional thermograph. This study also demonstrates the performance of the present system by imaging the temperature of objects with different emissivities and at different temperatures. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(6): 473–488, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10104
Effects of physiological isotonic cryoprotectants on living cells during the freezing–thawing process and effects of their uptake by electroporation: Sp2 cells in alginate–trehalose solutions
Authors: Shirakashi Ryo , Müller Kilian J. , Sukhorukov Vladimir L. , Zimmermann Ulrich
Published: August 2003

In the present study, effects of isotonic alginate and trehalose solutions on electroporated and unpulsed control murine myeloma cells (Sp2 line) during the freezing–thawing process were evaluated. To investigate the effects of these potential cryoprotectants, microscopic examination of cell suspensions in alginate–NaCl, alginate–trehalose, or trehalose media was performed during freezing–thawing at various cooling/warming rates (e.g., −1, −5, and −90 °C/min). It was found that, even at the lowest cooling rate, extracellular ice grains did not mechanically suppress cells in the trehalose‐substituted medium. Moreover, at all cooling rates, intracellular ice nucleation seldom occurred in the presence of extracellular trehalose. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(6): 511–523, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10105
Simulation of the daily change of soil temperature under different conditions
Authors: Fan A.W. , Liu W.
Published: August 2003

In this paper, by employing a mathematical model which was established to describe the physical mechanisms of heat and mass transfer in unsaturated porous media, some comparisons between the daily changes of soil temperatures under five different conditions have been conducted. The numerical simulations show that the ambient temperature, solar radiant heat flux, soil initial water content, ambient wind speed, atmospheric relative humidity, and soil porosity exert significant effects on the daily change of soil temperature. The differences between the daily changes of soil temperatures in those cases are also discussed and analyzed, which may provide some useful information for agriculture applications. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(6): 533–544, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10106
A thermal dispersion model for single phase flow in porous media
Authors: Du Jianhua , Hu Xuejiao , Wu Wei , Wang Bu‐Xuan
Published: August 2003

A new model for thermal dispersion is proposed based on the character of flow in porous media which relates the dispersion with the velocity and the tortuosity of fluid flow in the pores. Compared with former similar models, this one has fewer adjustable empirical constants, and therefore it is expected to be used more conveniently. The prediction by the present model can successfully reproduce the temperature distributions in the nearby wall region when a single phase fluid flows through a packed channel. The results of Nu versus Re agree well with the experimental results. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(6): 545–552, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10107
Modeling of hot gas flow through a feed stream within a horizontal pipe
Authors: Hu G.X. , Xu W. , Liu Y.Q.
Published: August 2003

High heat penetration into a feed stream within a horizontal pipe is described mathematically with a gas flow and heat transfer model. Influences of varied factors on the gas flow and heat transfer in porous media are examined for different conditions. The temperature of the packed‐bed particles and the gas velocity distribution curves are obtained for the feeding service at interruption and at regular charge operating conditions. The numerical results show that the thermal effect to the packed‐bed particles by the seepage flow fluid is high only in the position near the gas entrance. The thermal penetration depth tends to increase with the seepage flow velocity and decrease with the feed rate. The operating conditions and the porosity of solid bed have importance effects on the gas velocity and temperature field in the thermal penetration zone. The model results are found to compare favorably with the experimental data available in the literature. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(6): 553–565, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10109
Effects of operating conditions on infiltration of molten aluminum and heat transfer in a centrifugal force field
Authors: Tian Qinwei , Hu Guoxin , Wang Guoshan
Published: August 2003

This paper presents the results of an analysis aimed at determining the influence of changing operating conditions in the centrifugal infiltration casting. It considers the effect of centrifugal force on infiltration and heat transfer. The molten aluminum flow with heat transfer though SiC porous media in a centrifugal force field is described using a mathematical and physical model by employing the local thermal nonequilibrium between the solid and fluid phases. The calculation results show that the temperature difference between molten aluminum and SiC porous media in the infiltrated region decreases with the contact time. There are two distinctly noticeable stages of infiltration velocity: the onset stage of infiltration, which drops down sharply, and the following stage of smooth velocity. The operating conditions have important effects on the infiltration velocity and temperature patterns of fluid and solid. A suitable rotational speed and SiC volume fraction should be chosen to ensure the flow of molten metal in the porous preform and diminish the temperature difference between fluid and solid. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(6): 501–510, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10114
The improvement of heat transfer efficiencies in cool‐thermal discharge systems with complete removal of melt
Authors: Ho Chii‐Dong , Wang Cheng‐Kuo , Wang Wen‐Pen
Published: August 2003

A new device of air time–velocity variations in cool‐thermal discharge systems from ice melting with complete melt removal was proposed and the mathematical formulation for calculating the outlet chilled air temperature with convective transfer by adjusting the air mass velocity on free ice surface was developed. The proposed device in this study is a technical feasibility in controlling the outlet chilled air temperature by adjusting the air mass velocity and enhancing heat transfer efficiency by removing melt with a maximum temperature gradient. Three numerical examples of the inlet ambient air temperature were illustrated for practical applications under complete melt removal, and hence the time history of the air mass velocity was also obtained for the desired outlet chilled air temperature. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(6): 524–532, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj/10119
Macrophage migration inhibitory factor: Roles in regulating tumor cell migration and expression of angiogenic factors in hepatocellular carcinoma
Authors: Ren Yi , Tsui Hong‐Teng , Poon Ronnie Tung‐Ping , Ng Irene Oi‐Lin , Li Zhi , Chen Yongxiong , Jiang Guoping , Lau Cecilia , Yu Wun‐Ching , Bacher Michael , Fan Sheung‐Tat
Published: August 2003

Macrophage migration inhibitory factor (MIF) may contribute to multiple aspects of tumor progression, including control of cell proliferation, differentiation, cell survival and angiogenesis. However, the potential roles of MIF in regulating hepatocellular carcinoma (HCC) tumor cell migration and the expression of angiogenic factors by HCC tumor cells have not been studied yet. In our study, we reported that intracellular MIF mRNA and protein were overexpressed in HCC tissues compared to nontumor tissues by using in situ hybridization and immunohistochemic staining. HCC tumor cell lines also secreted large amounts of MIF into the supernatants of tumor cell culture. To assess the role of MIF in HCC, we employed the transwell invasion chamber to study the effect of MIF on tumor cell migration. Our results showed that recombinant MIF and the supernatants of tumor cell line culture could enhance the invasion and migration of HCC cells. This effect can be inhibited by the addition of a neutralizing anti‐MIF antibody. We observed that increased MIF serum levels correlated with higher levels of interleukin‐8 (IL‐8) in the sera of patients with HCC than in normal volunteers. We therefore hypothesized that MIF may regulate the production of angiogenic factors by HCC cells. To test this hypothesis, we examined the effect of MIF treatment on vascular endothelial growth factor (VEGF) and IL‐8 expression by HCC cell lines. MIF induced a significant dose‐dependent increase in IL‐8 and VEGF production. Taken together, our results indicated that MIF may act as an autocrine‐acting factor that stimulates angiogenesis and metastasis in HCC by promoting expression of angiogenic factors and migration of tumor cells. A more detailed understanding of the MIF regulatory mechanisms involved may provide insight into new direction in the treatment of HCC. © 2003 Wiley‐Liss, Inc.
Hepatitis C virus NS5A as a potential viral Bcl‐2 homologue interacts with Bax and inhibits apoptosis in hepatocellular carcinoma
Authors: Chung Yih‐Lin , Sheu Meei‐Ling , Yen Sang‐Hue
Published: August 2003

Treatment of hepatocellular carcinoma (HCC) cells with butyrate can induce apoptosis irrespective of hepatitis B virus integration. No information is available, however, regarding the effect of butyrate on HCC in the presence of hepatitis C virus (HCV) because some HCV proteins can regulate cell survival. By gene transfer, we found that HCV core enhances but HCV NS5A antagonizes sodium phenylbutyrate (NaPB)‐induced apoptosis in HCC cells, which is independent of p53. We then chose the p53‐negative Hep3B HCC cell to investigate the mechanism of anti‐apoptosis mediated by NS5A. In the NaPB‐treated Hep3B cells without NS5A expression, induction of apoptosis was associated with Bax redistribution from the cytosol to the nucleus interior and subsequently, to a nuclear membrane‐bound form. In the NS5A expressing Hep3B cells, NaPB treatment also triggered relocalization of both Bax and NS5A from the cytosol to the nucleus interior but Bax retained inside the nucleus and did not finally move to the nuclear membrane. Using double immunofluorescence and coimmunoprecipitation, we demonstrated that NS5A co‐localizes and interacts with Bax in the nucleus. The HCV NS5A protein was further found to contain Bcl‐2 homology domains (BH3, BH1 and BH2). Additional studies using deleted NS5A constructs were carried out to determine whether the BH2 domain or nuclear localization signal (NLS) in NS5A is required for interaction with Bax in the nucleus or inhibition of apoptosis. NS5A with deletion of both BH2 domain and NLS localized in the cytoplasm, dissociated with Bax, and lost anti‐apoptosis activity during NaPB treatment. In contrast, NS5A with intact BH domains except NLS still bound directly to Bax in the perinuclear region or the nucleus, but showed less association with Bax in the nucleus and lower effect in apoptosis inhibition than full‐length NS5A. These results suggest that HCV NS5A as a Bcl‐2 homologue interacts with Bax to protect p53‐negative HCC cells from NaPB‐induced apoptosis. © 2003 Wiley‐Liss, Inc.
Esophageal cancer risk in relation to GGC and CAG trinucleotide repeat lengths in the androgen receptor gene
Authors: Dietzsch Erin , Laubscher Ria , Parker M. Iqbal
Published: August 2003

The incidence of esophageal squamous cell cancer in African males in South Africa is one of the highest in the world. Because most patients present with advanced disease such that survival is poor, the identification of high‐risk individuals will facilitate early disease detection. Two polymorphic triplet repeats—(CAG)n and (GGC)n—in the androgen receptor gene were evaluated as potential genetic susceptibility loci for esophageal squamous cell cancer. Shorter lengths of these alleles have been reported to be associated with increased risk for prostate cancer. Our study sample comprised African males (29 patients and 109 controls), African females (14 patients and 59 controls) and Colored males (15 patients and 58 controls) whose alleles were analyzed singly and in combination. As in prostate cancer, the short (GGC)n alleles were implicated in esophageal cancer in African males: the average allele length was significantly shorter in patients compared to controls (p = 0.018), and a short (GGC)n allele was associated with elevated risk for disease [(GGC)≤16 odds ratio (OR) 2.7, 95% confidence interval (CI) 1.14–6.36; (GGC)≤14 OR 3.3, 95% CI 1.29–8.44]. There was no evidence, however, that short (CAG)n repeat alleles increased susceptibility to the disease. When the 2 alleles were considered jointly, additional information on predisposition was gained, revealing 2 haplotypes conferring a protective effect, i.e., [(CAG)>21 (GGC)≤16] OR 0.31, 95% CI 0.11–0.88; [(CAG)≤21 (GGC)>16] OR 0.26, 95% CI 0.11–0.65. Analysis using logistic regression led to narrower CIs for the ORs and enabled presentation of a risk profile. © 2003 Wiley‐Liss, Inc.
Influence of TNFA on the formation of liver metastases in a syngenic mouse model
Authors: Sturm Jörg W. , Magdeburg Richard , Berger Kristine , Petruch Beate , Samel Stefan , Bönninghoff Roderich , Keese Michael , Hafner Mattias , Post Stefan
Published: August 2003

The level of TNFα expression is increased after partial hepatectomy, and experimental evidence exists that TNFα plays a key role in liver regeneration. Contradictory results are reported about the influence of TNFα on tumor growth: on the one hand, stimulation of tumor growth in various animal models and, on the other hand, intraperitoneally administered TNFα leads to reduced metastasis formation. TNFα may be one responsible factor for increased metastasis formation after surgical trauma. The objective of our study was to clarify the influence of TNFα on the formation of liver metastases in a syngenic mouse model in vivo. We used a novel marker system, EGFP transfected C26 tumor cells for in vivo observation of metastasis formation by intravital microscopy. We analyzed the effect of intraperitoneal TNFα‐injection on tumor cell adhesion, extravasation and tumor development. The expression of ICAM‐1, VCAM‐1 and E‐Selectin was measured by Western blot and immunohistochemical staining. Tumor load was assessed by determining EGFP in Western blots. GdCl3 was employed 24 and 48 hr before tumor cell injection to selectively deplete the liver of functioning Kupffer cells. We observed significantly more extravasated tumor cells in the TNFα‐pre‐treated animals at early time points with increased expression of adhesion molecules. Measurement of the EGFP levels showed fewer liver metastases in the TNFα‐pretreated animals at day 8. After GdCl3 pretreatment even lower levels of EGFP, i.e., fewer metastases and also lower expression levels of ICAM‐1, VCAM‐1 and E‐Selectin could be observed. TNFα, acts in a bidirectional manner: whereas TNFα facilitates tumor cell adhesion and extravasation of C26 tumor cells by inducing the expression of adhesion molecules, at later time points, TNFα seems to hinder the formation of liver metastases. © 2003 Wiley‐Liss, Inc.
High simian T‐cell leukemia virus type 1 proviral loads combined with genetic stability as a result of cell‐associated provirus replication in naturally infected, asymptomatic monkeys
Authors: Gabet Anne‐Sophie , Gessain Antoine , Wattel Eric
Published: August 2003

Simian T‐cell leukemia virus type 1 (STLV‐1) is a primate T cell leukemia virus of the group of oncogenic delta retroviruses. Sharing a high level of genetic homology with human T cell leukemia virus type 1 (HTLV‐1), it is etiologically linked to the development of simian T cell malignancies that closely resemble HTLV‐1 associated leukemias and lymphomas and might thus constitute an interesting model of study. The precise nature of STLV‐1 replication in vivo remains unknown. The STLV‐1 circulating proviral load of 14 naturally infected Celebes macaques (Macaca tonkeana) was measured by real‐time quantitative PCR. The mean proportion of infected peripheral mononuclear cells was 7.9%, ranging from <0.4% to 38.9%. Values and distributions were closely reminiscent of those observed in symptomatic and asymptomatic HTLV‐1 infected humans. Sequencing more than 32 kb of LTRs deriving from 2 animals with high proviral load showed an extremely low STLV‐1 genetic variability (0.113%). This paradoxical combination of elevated proviral load and remarkable genetic stability was finally explained by the demonstration of a cell‐associated dissemination of the virus in vivo. Inverse PCR (IPCR) amplification of STLV‐1 integration sites evidenced clones of infected cells in all infected animals. The pattern of STLV‐1 replication in these asymptomatic monkeys was indistinguishable from that of HTLV‐1 in asymptomatic carriers or in patients with inflammatory diseases. We conclude that, as HTLV‐1, STLV‐1 mainly replicates by the clonal expansion of infected cells; accordingly, STLV‐1 natural monkey infection constitutes an appropriate and promising model for the study of HTLV‐1 associated leukemogenesis in vivo. © 2003 Wiley‐Liss, Inc.
Role of the stromal microenvironment in carcinogenesis of the prostate
Authors: Cunha Gerald R. , Hayward Simon W. , Wang Y.Z. , Ricke William A.
Published: August 2003

The topic of this review is the role of stromal‐epithelial interactions in normal and malignant prostatic growth. Because cell‐cell interactions and androgens play such key roles in the prostate, the goal of this review will be to apply endocrinologic and developmental concepts to the understanding of normal and malignant prostatic growth. Prostatic development is induced by androgens, which act via androgen receptors. Androgens elicit prostatic epithelial growth during fetal and prepubertal periods, and in adulthood androgens act via reciprocal homeostatic stromal‐epithelial interactions to maintain functional differentiation and growth quiescence. During carcinogenesis, these reciprocal homeostatic stromal‐epithelial interactions are disrupted. In this review, 2 models of prostatic carcinogenesis will be reviewed, both of which emphasize the role of the stromal microenvironment in the carcinogenic process. Hormonal carcinogenesis of the prostate can be elicited by treatment of rats and mice with testosterone plus estradiol (T+E2). Using an immortalized but nontumorigenic human prostatic epithelial cell line (BPH‐1), tissue recombinant studies were employed to explore the cellular mechanisms of prostatic carcinogenesis. Accordingly, human BPH‐1 prostatic epithelial cells were combined with rat UGM, and the resultant UGM+BPH–1 recombinants were grown in adult male nude mouse hosts. In untreated mouse hosts, UGM+BPH–1 recombinants produced solid branched epithelial cords and ductal structures exhibiting benign growth. In T+E2‐treated hosts, UGM+BPH–1 recombinants formed invasive carcinomas. Since BPH‐1 cells lack androgen and estrogen receptors, whereas rat UGM expresses both of these receptors, it is proposed that hormonal carcinogenesis is elicited by T+E2 via paracrine mechanisms mediated by the stromal microenvironment. During prostatic carcinogenesis in rats and humans, the periepithelial stroma undergoes progressive loss in smooth muscle with the appearance of carcinoma‐associated fibroblasts (CAFs). This abnormal stroma was shown to promote carcinogenesis in genetically abnormal but nontumorigenic epithelial cells. CAF+BPH‐1 tissue recombinants grown in male hosts formed carcinomas, whereas benign growth and orderly tissue architecture developed in recombinants composed of normal prostatic stroma+BPH‐1. Malignant transformation triggered by CAF was associated with additional genetic alterations and changes in gene expression in the BPH‐1 cells. Thus, the stromal microenvironment is a critical determinant of benign versus malignant growth. © 2003 Wiley‐Liss, Inc.
Sensitization of ara‐C‐resistant lymphoma cells by a pronucleotide analogue
Authors: Galmarini Carlos María , Clarke Marilyn L. , Santos Cheryl L. , Jordheim Lars , Perigaud Christian , Gosselin Gilles , Cros Emeline , Mackey John R. , Dumontet Charles
Published: August 2003

Adequate intracellular concentrations of ara‐CMP, the monophosphorylated derivative of ara‐C, are essential for its cytotoxicity. The critical step for ara‐CMP formation is intracellular phosphorylation of ara‐C by deoxycytidine kinase (dCK). A common nucleoside resistance mechanism is mutation affecting the expression or the specificity of dCK. We describe the ability of a tert‐butyl S‐acyl‐thioethyl (SATE) derivative of ara‐CMP (UA911) to circumvent ara‐C resistance in a dCK‐deficient human follicular lymphoma cell line (RL‐G). The RL‐G cell line was produced by continuous exposure to gemcitabine and displayed low dCK mRNA and protein expression that conferred resistance both to ara‐C (2,250‐fold) and to gemcitabine (2,092‐fold). RL‐G cells were able to take up the UA911 pronucleotide by diffusion and metabolize it to the corresponding ara‐CMP and ara‐CTP nucleotides, exhibiting a 199‐fold reduction in resistance ratios, and a similar cell cycle arrest to the parental RL‐7 cells. Exposures to 10, 50 or 100 μM concentrations of UA911 produced 160 ± 7, 269 ± 8 and 318 ± 62 pmol ara‐CTP/mg protein in RL‐7 cells, and 100 ± 12, 168 ± 10 and 217 ± 39 pmol ara‐CTP/mg protein in RL‐G cells, respectively. Exposure of RL‐G cells to underivatized, radiolabeled ara‐C produced no detectable amounts of the active triphosphate metabolites. We conclude that the UA911 pronucleotide is capable of overcoming dCK‐mediated resistance. This result can be attributed to the unique cellular metabolism of the SATE pronucleotides giving rise to the intracellular delivery of ara‐CMP to dCK‐deficient cells. © 2003 Wiley‐Liss, Inc.
Mast cell inhibitor cromolyn increases blood clotting and hypoxia in murine breast cancer
Authors: Samoszuk Michael , Corwin Mark A.
Published: August 2003

Human breast cancer is extensively infiltrated by mast cells that contain powerful anticoagulants such as heparin, tryptase and chymase. To determine if human breast cancer is associated with mast cell activation, we measured the levels of mast cell tryptase (an indicator of mast cell activation) in the blood of 20 women with varying stages of breast cancer. The mean level of tryptase in women with breast cancer (10.3 ± 4.2 μg/L) was significantly higher than in 50 normal healthy women without breast cancer (3.0 ± 2.5 μg/L, p < 0.05 by two‐tailed t‐test). To explore the role of mast cells in breast cancer in more detail, we then carried out experiments that were aimed at determining if an inhibitor of mast cell function, sodium cromolyn, could increase blood clotting and hypoxia within subcutaneous implants of the 4T1 mammary adenocarcinoma cell line in mice. We treated tumor‐bearing mice with 5 consecutive daily doses of sodium cromolyn (10 mg/kg, i.p.). An average of 30% of the periphery of the tumors from the 5 drug‐treated mice contained large lakes of clotted blood that were not evident in any of the tumors from the control (untreated) mice. By computerized image analysis of tumors immunostained for a hypoxia marker (pimonidazole), the tumors from the treated mice had significantly more hypoxia (35 ±12 % hypoxic regions, n = 5) than the tumors from untreated (control) mice (16 ± 7%, n = 5). We conclude that sodium cromolyn enhanced peri‐tumoral blood clotting and intratumoral hypoxia. These results suggest that mast cells may play an important role in regulating blood clotting and hypoxia within breast cancer. © 2003 Wiley‐Liss, Inc.
Spindle assembly checkpoint defects and chromosomal instability in head and neck squamous cell carcinoma
Authors: Minhas Khalid M. , Singh Bhuvanesh , Jiang Wei‐wen , Sidransky David , Califano Joseph A.
Published: August 2003

Alterations in chromosomal number and structure are found in most solid malignancies including head and neck squamous cell carcinoma (HNSC), however, the presence of ongoing, chromosomal instability in HNSC and its relation to spindle assembly checkpoint defects has not been formally demonstrated. We investigated the status of chromosomal instability (CIN) in HNSC primary tumors and cell lines as well as spindle assembly checkpoint integrity in HNSC cell lines. Centromeric fluorescence in situ hybridization (FISH) was carried out on expanded single cell‐derived colonies from HNSC cell lines and primary HNSC touch preparations. The deviation of chromosomes from the modal number in single cell derived colonies was 18.4–27% in 6 HNSC cell lines, and 2–3% in a control cell line, HCT116. Twelve primary tumors and 4 normal controls were also studied; all primary tumors demonstrated significant deviation from the modal chromosomal number (average 33.7%, range = 29.9–43.9%), compared to normal controls (average 4.6%, range = 3.6–5.6%). Additional characterization of the rate of chromosomal breakage was carried out by dual color FISH simultaneously using centromeric and telomeric probes for individual chromosomes on expanded singe cell‐derived colonies and primary HNSC. Control HCT 116 colonies demonstrated a mean discordance between number of centromeric and telomeric hybridization signals in 21% (range = 19–23%) of cells, whereas HNSC cell line colonies demonstrated a mean discordance of 50% (range = 38–55%), with the majority of instances of discordant signal indicating telomeric loss. Similarly, touch preparations from primary HNSC demonstrated discordance in hybridization signal of centromeric vs. telomeric signal of 26.3% (range = 18.5–42%), with normal controls showing a rate of discordance of 6.4% (range = 4–8%). Finally, all 6 HNSC cell lines demonstrated partial impairment of mitotic arrest in response to nocodazole, indicating that impairment of the spindle assembly checkpoint may contribute to chromosomal instability in HNSC. Ongoing instability in chromosomal number and structure are consistent features of primary HNSC and cell lines. Spindle assembly checkpoint impairment occurs in HNSC cell lines and may contribute to chromosomal instability in HNSC. © 2003 Wiley‐Liss, Inc.
Smoking and liver cancer in China: Case‐control comparison of 36,000 liver cancer deaths vs. 17,000 cirrhosis deaths
Authors: Chen Zheng‐ming , Liu Bo‐qi , Boreham Jillian , Wu Ya‐ping , Chen Jun‐shi , Peto Richard
Published: August 2003

Liver cancer and liver cirrhosis are common causes of death in China, where chronic lifelong hepatitis B infection is a major cause of both diseases. To help determine whether smoking is a cofactor for the development of liver cancer, we ascertained retrospectively the smoking habits of 36,000 adults who had died from liver cancer (cases) and 17,000 who had died from cirrhosis (controls) in 24 Chinese cities and 74 rural counties. Calculations of the smoker vs. nonsmoker risk ratios (RR) for liver cancer mortality were standardised for age and locality. Among adult men (aged 35+) there was a 36% excess risk of death from liver cancer among smokers (smoker vs. nonsmoker standardised risk ratio [RR] =1.36, with 95% confidence interval [CI] 1.29–1.43, 2p<0.00001; attributable fraction 18%). In the general male population this indicates absolute risks of death from liver cancer before age 70 of about 4% in smokers and 3% in nonsmokers (in the absence of other causes). Most liver cancer, however, occurs among the 10–12% of men with haematological evidence of chronic hepatitis B infection, so among them the corresponding risks would be about 33% in smokers and 25% in nonsmokers. The RR was approximately independent of age, was similar in urban and rural areas, was not significantly related to the age when smoking started but was significantly (p<0.001) greater for cigarette smokers than for smokers of other forms of tobacco. Among men who smoked only cigarettes, the RR was significantly (p<0.001 for trend) related to daily consumption, with a greater hazard among those who smoked 20/day (RR 1.50, 95% CI 1.39–1.62) than among those who smoked fewer (mean 10/day: RR=1.32, 95% CI 1.23–1.41). Smoking was also associated with a significant excess of liver cancer death in women (RR 1.17, 95% CI 1.06–1.29, 2p=0.003; attributable fraction 3%), but fewer women (17%) than men (62%) were smokers, and their cigarette consumption per smoker was lower. Among women who smoked only cigarettes, there was a significantly greater hazard among those who smoked at least 20/day (mean 22/day: RR=1.45, 95% CI 1.18–1.79) than among those who smoked fewer (mean 8/day: RR=1.09, 95% CI 0.94–1.25). These associations indicate that tobacco is currently responsible for about 50,000 liver cancer deaths each year in China, chiefly among men with chronic HBV infection. © 2003 Wiley‐Liss, Inc.
Mutational analysis of the LMO4 gene, encoding a BRCA1‐interacting protein, in breast carcinomas
Authors: Sutherland Kate D. , Visvader Jane E. , Choong David Y.H. , Sum Eleanor Y.M. , Lindeman Geoffrey J. , Campbell Ian G.
Published: August 2003

The LIM domain‐only genes LMO1 and LMO2 are translocated in acute T cell leukemia (T‐ALL) and have been shown to be oncogenes in T lymphoid cells. LMO4, the fourth member of this family, is overexpressed in more than 50% of sporadic breast cancers, suggesting a role in breast oncogenesis. We recently found that LMO4 interacts with the breast/ovarian tumor suppressor BRCA1 and that LMO4 can repress its transcriptional activity. Since proto‐oncogene deregulation can result from activating mutations in their coding or regulatory sequences, we explored whether the LMO4 gene undergoes somatic mutagenesis in breast cancer. Mutation analysis of the coding and 3′ untranslated regions of the LMO4 gene was performed on 82 primary breast and 22 tumor cell lines. A somatic mutation was detected in one primary breast cancer, at the 3′ end of exon 2, but was not present in normal DNA derived from the same patient. This mutation causes a frame‐shift and potentially results in a truncated LMO4 polypeptide, LIM1mut, lacking the second LIM domain. This mutant protein could still bind Ldb1 but no longer associated with CtIP or BRCA1. Our results show that somatic mutations within the LMO4 gene do occur in breast cancer but at a very low frequency. Thus, the primary mechanism by which LMO4 is deregulated in breast cancers appears to reflect overexpression of the gene rather than the acquisition of activating genetic mutations. © 2003 Wiley‐Liss, Inc.
Negative regulatory role of PI3‐Kinase in TNF‐induced tumor necrosis
Authors: Matschurat Susanne , Blum Sabine , Mitnacht‐Kraus Rita , Dijkman Henry B.P.M. , Kanal Levent , de Waal Robert M.W. , Clauss Matthias
Published: August 2003

Tissue factor is the prime initiator of blood coagulation. Expression of tissue factor in tumor endothelial cells leads to thrombus formation, occlusion of vessels and development of hemorrhagic infarctions in the tumor tissue, often followed by regression of the tumor. Tumor cells produce endogenous vascular endothelial growth factor (VEGF), which sensitizes endothelial cells for systemically administered tumor necrosis factor α (TNF α) and synergistically enhances the TNF‐induced expression of tissue factor. We have analyzed the pathways involved in the induction of tissue factor in human umbilical cord vein endothelial cells (HUVECs) after combined stimulation with TNF and VEGF. By using specific low molecular weight inhibitors, we demonstrated that protein kinase C (PKC), p44/42 and p38 mitogen‐activated protein (MAP) kinases, and stress‐activated protein kinase (JNK) are essentially involved in the induction of tissue factor. In contrast, the application of wortmannin, an inhibitor of phosphatidylinositol 3 (PI3)‐kinase, led to strongly enhanced expression of tissue factor in TNF‐ and VEGF‐treated cells, implicating a negative regulatory role for PI3‐kinase. In vivo, the application of wortmannin promoted the formation of TNF‐induced hemorrhages and intratumoral necroses in murine meth A tumors. The co‐injection of wortmannin lowered the effective dose of applied TNF. Therefore, it is conceivable that the treatment of TNF‐sensitive tumors with a combination of TNF and wortmannin will ensure the selective damage of the tumor endothelium and minimize the risk of systemic toxicity of TNF. TNF‐treatment in combination with specific inhibition of PI3‐kinase is a novel concept in anti‐cancer therapy. © 2003 Wiley‐Liss, Inc.