bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterogeneity in nuclear transport does not affect the timing of DNA synthesis in quiescent mammalian nuclei induced to replicate in Xenopus egg extracts
Authors: Sun W.‐H. , Hola M. , Baldwin N. , Pedley K. , Brooks R.F. 
Published: March 2003

Abstract.Intact G0 nuclei from quiescent mammalian cells initiate DNA synthesis asynchronously in Xenopus egg extracts, despite exposure to the same concentration of replication factors. This indicates that individual nuclei differ in their ability to respond to the inducers of DNA replication. Since the induction of DNA synthesis requires the accumulation of replication factors by active nuclear transport, any variation in the rate of transport among nuclei could contribute to the variability of DNA replication. Using the naturally fluorescent protein allophycocyanin (APC) coupled with the nuclear localization sequence (NLS) of SV40 T antigen, as a marker of nuclear uptake, we show here that individual G0 nuclei differ in their rate of transport over a range of more than 20‐fold. Surprisingly, this variation has no direct influence on the timing or extent of DNA synthesis. Similar results were obtained by monitoring the uptake of nucleoplasmin, a nuclear protein present at high levels in egg extracts. These experiments show that the initiation of DNA synthesis is not driven merely by the accumulation of replication factors to some threshold concentration. Instead, some other explanation is needed to account for the timing of initiation.
Establishment of a tetraploid Meth‐A cell line through polyploidization by demecolcine but not by staurosporine, K‐252A and paclitaxel
Authors: Fujikawa‐Yamamoto K. , Wang S. , Yamagishi H. , Ohdoi C. , Murano H. , Ikeda T. 
Published: March 2003

Abstract.Polyploid cells are made by DNA reduplication without cell division, however, it is not easy to establish polyploid mammalian cell lines. It is worth studying the difference in cell character between hyperploid and parent cell lines. Meth‐A cells were polyploidized by demecolcine, K‐252a, staurosporine and paclitaxel. The cell‐cycle responses of highly polyploid Meth‐A cells after the removal of the drugs were examined by flow cytometry (FCM). Meth‐A cells were highly polyploidized by these drugs. The polyploid Meth‐A cells gradually decreased in ploidy after the drug release. A tetraploid Meth‐A cell line was established only from the demecolcine‐induced polyploid Meth‐A cells. The duration of G1, S and G2/M phases of the tetraploid cell line were mostly the same as those of the parent diploid cells, except that the G2/M phase was 1.5 h longer. The chromosome number of tetraploid Meth‐A cell line was about twice of the diploidy. A tetraploid Meth‐A cell line was established.
Use of real time leukaemia data to validate model predictions based on analyses and computer simulations
Authors: Afenya E. K. 
Published: March 2003

Abstract.Predictions arising out of a mathematical model that describes the expansion of leukaemia from a diffusion‐orientated perspective are critiqued and validated by employing available real time data. Based on agreements found between model predictions and the data, but mindful of the limitations it presents, it is concluded that the model could be used to describe the dynamics of normal and abnormal cells in leukaemia. It is suggested that further studies of the behaviour of certain normal cell types in contrast to abnormal cells during leukaemic development could engender additional insights into leukaemia and its treatment.
Stimulation of DNA synthesis, activation of mitogen‐activated protein kinase ERK2 and nuclear accumulation of c‐fos in human aortic smooth muscle cells by ketamine
Authors: Boulom V. , Lee H.‐W. , Zhao L. , Eghbali‐Webb M. 
Published: March 2003

Abstract. Proliferation of vascular smooth muscle cells is known to be regulated by autocrine and paracrine stimuli, including extracellular matrix, reactive oxygen species, lipids, and biomechanical forces. The effect of many pharmacological agents to which smooth muscle cells may be exposed, however, is widely unexplored. Ketamine, an intravenous anaesthetic and a phencyclidine derivative, regulates diverse intracellular signalling pathways in smooth muscle cells, several of which are known to affect cell proliferation. The effect of ketamine on proliferative response of smooth muscle cells, however, is not determined. We tested the hypothesis that ketamine may regulate proliferation of smooth muscle cells, and investigated the effects of pharmacological doses of ketamine on their proliferative capacity by measuring DNA synthesis and activation of mitogen‐activated protein (MAP) kinase signalling pathway in human aortic smooth muscle cells. DNA synthesis, as determined by incorporation of 3H‐thymidine into DNA, was enhanced by 73% (P < 0.0001) and 130% (P < 0.0001) with 10 and 100 µm ketamine, respectively. Ketamine‐induced DNA synthesis was dependent on de novo protein synthesis, as it was abolished by an inhibitor of protein synthesis, cycloheximide. A synthetic inhibitor of MAP kinase pathway, PD98059, decreased 50% (P < 0.0001) of ketamine‐induced DNA synthesis, suggesting that the activation of MAP kinase pathway was partially responsible for ketamine‐induced effects. Consistently, in‐gel kinase assay and in vitro kinase assay of cell lysates showed ketamine‐induced MAP kinase activation and expression of ERK2 (extracellular signal‐regulated kinase) in smooth muscle cells. This effect of ketamine was not dependent on de novo protein synthesis. Immunofluorescent light microscopy showed ketamine‐induced nuclear accumulation of c‐fos, a downstream effect of MAP kinase activation, in smooth muscle cells. In conclusion, these data support the hypothesis of the study and demonstrate that ketamine, by stimulating DNA synthesis in human aortic smooth muscle cells, may have an impact on proliferative capacity of these cells. The present results also demonstrate that ketamine induces the activation of MAP kinase pathway and nuclear accumulation of transcription factor c‐fos in smooth muscle cells. They further demonstrate that the activation of MAP kinases is partially responsible for ketamine‐induced DNA synthesis in human aortic smooth muscle cells. Together, these findings suggest that ketamine may play a role as a pharmacological regulator of mechanisms involved in proliferation of smooth muscle cells.
Proliferation of glial cells induced by lithium in the neural lobe of the rat pituitary is enhanced by dehydration
Authors: Levine S. , Saltzman A. , Katof B. , Meister A. , Cooper T. B. 
Published: March 2003

Abstract. Rats dehydrated by 6 days of water deprivation had a low level of mitotic activity in the astrocytes (‘pituicytes’) of the neural lobe of the pituitary. Mitotic activity in the pituicytes was greatly increased when isotonic lithium was administered in the last 3 days of water deprivation. Rehydration on the last day of the experiment produced a further increase in mitoses. Isotonic solutions of sodium, potassium or rubidium chloride did not increase mitoses. This model of cell proliferation is of interest because the mitotic activity is related to a physiological attempt to maintain homeostasis rather than a response to injury or the development of neoplasia.
Responding to child sexual abuse: an evaluation of social work by children and their carers
Authors: Prior  , Lynch  , Glaser  
Published: March 2003

This paper presents the views and perceptions of 35 children and their current carers regarding the social work response to child sexual abuse. Interviews with the children and carers, including foster carers and residential carers, were carried out 2–4 years following disclosure, thus the nature of social work support in the longer term, as well as the initial response, is assessed and described. Three evaluations of social work support are presented: the child‐ren’s evaluations of social workers known since disclosure, and two evaluations from the carers, one focusing on the child’s needs, and one focusing on their own as carers. All three evaluations perceived the majority of social workers as having helped. Aspects of social work considered essential included providing emotional support and reassurance, providing information and explanation and arrang‐ing and coordinating services, including counselling or therapy. Carers of children who were abused by someone outside the family were less likely to receive social work support. The frustra‐tion and disappointment expressed by some of these carers reaffirms the importance of assessing needs even when the child is considered protected from further abuse. The findings of this study support the need to refocus responses to abused children and their families.
The transition of Israeli men to fatherhood: a comparison between new fathers of pre‐term/full‐term infants
Authors: Rimmerman Arie , Sheran Haviva 
Published: March 2003

ABSTRACTThe study compared a group of 62 new Israeli fathers of pre‐term infants with a comparison group of 58 new fathers of full‐term infants with respect to parental stress, depression symptoms, mastery, self‐esteem and involvement with the child. Findings indicated that fathers of pre‐term infants had significantly greater stress and depression scores and lower involvement rate with the child compared with fathers of the matching group. No differences were found with respect to the fathers' mastery and self‐esteem. New fathers of full‐term infants, aged 30 years and more, had significantly higher self‐esteem compared with fathers aged less than 30 years. Findings are discussed with respect to practice in neonatal units.
Promoting children's rights through the use of relationship
Authors: Bell Margaret 
Published: March 2003

ABSTRACTThis paper reports on a research study exploring the views of 27 children and young people on their involvement in a child protection investigation. Their perspectives on the personal and professional qualities of the professionals involved and on the choice, influence and representation they experienced and prefer are discussed. One of the most striking findings is that most of the children and young people had experienced a positive relationship with a social worker. Overall, many reported improvements at home, at school and in their health and behaviour. Their responses to different aspects of the intervention are discussed within the context of their rights to participation, choice and representation. It is acknowledged that children lack agency in promoting these rights in child protection work and concluded that these are best promoted through the development and maintenance of a relationship of trust, offered by a key professional in their network. Drawing upon Heard & Lake's (1997) work on attachment theory, it is suggested, further, that relationships and processes which embody supportive and companionable interactions are more likely to offer opportunities for representation and participation than those which are dominant and submissive. Finally, it is argued that children's services should be based on a human rights perspective, the discourse of which has more in common with the values of respect and honesty than with cost effectiveness and business management.
Social welfare services for single parent families in Hong Kong: a paradox
Authors: King Lau Yuk 
Published: March 2003

ABSTRACTThis paper argues that researchers and social workers, whose work aims at empowering single parent families, have inadvertently participated in a social construction process that reinforces a pathological perspective on these families. The process has paradoxically caused single parent families to be disempowered through a welfare service system that pinpoints their difficulties and vulnerabilities. To address the paradox, the author recommends a ‘both–and’ perspective that takes into account both the needs and difficulties, and the strengths and successes, of these families.
What do we know about child neglect? A critical review of the literature and its application to social work practice
Authors: Tanner Karen , Turney Danielle 
Published: March 2003

ABSTRACTChild neglect is a difficult and complex area of practice for social workers and other childcare professionals. To work effectively, practitioners need a good grasp of relevant literature and research – a point underlined by the moves to incorporate ‘research mindedness’ and ‘research literacy’ into social work education, training and practice. This paper aims to contribute to the debate around research literacy by looking in more detail at the research and knowledge base informing work with neglected children and their families, and considering the ways in which this can be applied in practice.In the first part of the paper, we provide a critical overview of the main aspects of research knowledge, summarizing ‘what we know’ currently about child neglect. Next, we look at some of the difficulties associated with this body of knowledge and at some of its limitations. Having noted these concerns, however, we go on to suggest ways in which the research evidence can be used in mainstream social work. We draw out some of the consequences for work with children and with their parents as well as considering the implications for social workers and their agencies.
Emotional reactions in parents and children after diagnosis and treatment of a malignant tumour in the eye
Authors: Ek U 
Published: March 2003

SummaryRetinoblastoma is a rare malignant tumour in the retina usually presenting before 3 years of age. In Sweden, 6–7 new cases are diagnosed each year. The medical treatment is highly specialized, very effective, with a survival ratio of almost 100%. Very little was known about the emotional and psychosocial effects on the parents and the patients themselves. This study includes all children diagnosed in Sweden between 1992 and 1994. The parents and children were included in our longitudinal support programme immediately after the diagnosis was made. This paper deals with the following topics: how the illness was detected and diagnosed, how the parents were handled by the health professionals, the parents' emotional reactions to the diagnosis and treatment and how the children reacted to the disease and treatment. Children's concepts of illness and acute loss are discussed.
Teamwork in Swedish neuropaediatric habilitation
Authors: Thylefors I , Price E , Persson O , Wendt L von 
Published: March 2003

SummaryTeam collaboration in Swedish paediatric habilitation was analysed by means of a nation‐wide sample of 202 professionals, representing all seven professions normally working in these teams. Provision of paediatric habilitation services as a part of the county secondary level health care is required by law, and has gradually been built up from the 1950s. The study focused on professional co– operation and interaction during different types of formal team meetings. The basic obstacles for the meetings were lack of time, poor meeting technique, and too large a group. The professionals appeared to interact on a fairly equal basis, able to challenge other's views and gaining a hearing for their own views, with the physiotherapists and the paediatricians perceived as being the most dominant team members. The perceived significance of the contribution from the different team members' dominance varied according to the age of the child and to changing needs. The prerequisites for interdisciplinary team working exist as far as meeting structure and a ‘democratic’ pattern of communication during meetings.
Prevalence and morbidity associated with non‐malignant, life‐threatening conditions in childhood
Authors: Lenton S , Stallard P , Lewis M , Mastroyannopoulou K 
Published: March 2003

SummaryObjective To determine the prevalence of non‐malignant life‐threatening illness in childhood and associated morbidity in the affected child and their family members.Design Cross‐sectional survey.Setting Bath Clinical Area (total population 411 800).Subjects Children aged 0–19 years.Results One hundred and twenty‐three children were identified, giving a prevalence of 1.2/1000 children. Morbidity assessed in 93 children showed 60% in pain or discomfort, 35% unable to walk and 25% with severe cognitive impairment. Mental health problems were found in 54% of mothers and 30% of fathers, and significant emotional and behavioural problems in 24% of healthy siblings.Conclusions Non‐malignant life‐threatening illness is more prevalent than reported in previous studies. Considerable morbidity is experienced by the child and their family. An individual and family approach is required.Key messages (1) The prevalence of non‐malignant life‐threatening illness is four times greater than previous estimates. (2) This group of conditions have significant implications for all family members. (3) Early comprehensive assessment and access to effective interventions may pre‐empt later problems.
Why is smoking a risk factor for Sudden Infant Death Syndrome?
Authors: Gordon A. E. , Ahmer O. R. El , Chan R. , Madani O. M. Al , Braun J. M. , Weir D. M. , Busuttil A. , Blackwell C. C. 
Published: March 2003

AbstractSmoking is a major risk factor for both Sudden Infant Death Syndrome (SIDS) and respiratory tract infections. Such infections, both viral and bacterial, also increase the SIDS risk. This study investigated the effect of cigarette smoke at two stages of infection: 1) mucosal surface colonization; 2) induction and control of inflammatory responses. For colonization, RSV or influenza A infected cells bound several bacterial species in significantly higher numbers due to increased expression of host cell antigens. Buccal epithelial cells from smokers bound significantly more bacteria. For Staphylococcus aureus, this was associated with increased tar levels. Some SIDS deaths have been proposed to result from high levels of pro‐inflammatory mediators elicited by infection and/or cigarette smoke during a developmental period when infants are less able to control inflammatory responses. Inflammatory reponses were compared between blood samples from smokers (n = 42) and non‐smokers (n = 60) stimulated with TSST‐1 or LPS. Non‐smokers had significantly higher IL‐6 (P = 0.011), IFN (P = 0.003) and IL‐10 (P = 0.000) baseline levels. Non‐smokers had higher IFN (P = 0.008) and IL‐1 (P = 0.001, 0.007) responses to LPS and higher IL‐10 responses to TSST‐1 (P < 0.05) and LPS (P < 0.000). This study highlights that smoking increases the SIDS risk by greater susceptibility to viral and bacterial infections and enhanced bacterial binding after passive coating of mucosal surfaces with smoke components. In animal models, IL‐10 reduced the lethal effect of staphylococcal toxins. In this study, smokers had lower IL‐10 responses to TSST‐1 and LPS. Dose response effects of cigarette smoke exposure needs to be established in relation to inflammatory response control and infantile infections.
Evidence for a genetic component in Sudden Infant Death Syndrome
Authors: Gordon A. E. , MacKenzie D. A. C. , Ahmer O. R. El , Madani O. M. Al , Braun J. M. , Weir D. M. , Busuttil A. , Blackwell C. C. 
Published: March 2003

AbstractThere is increasing evidence that inflammatory responses have been elicited in some Sudden Infant Death Syndrome (SIDS) infants and that these responses are under genetic control. The objective of this study was to investigate the hypothesis that the cytokine responses of SIDS parents (n = 41) differed significantly from control donors (n = 61). Blood samples were stimulated with the staphylococcal toxin TSST‐1 and LPS from Eschericia coli and assessed for production of TNF, IL‐1, IL‐6, IFN and IL‐10. In response to TSST‐1 (P < 0.02) and LPS (P < 0.002), SIDS parents produced higher levels of IL‐1 than the controls. SIDS parents produced higher levels of IFN in response to TSST‐1 compared to LPS (P < 0.001) although in response to LPS, the IFN (P = 0.0008) and IL‐6 (P < 0.0002) responses of the SIDS parents were lower than those of the controls. For TNF and IL‐10, there was little difference between the two groups unless the effect of smoking was considered. As part of this work, a small pilot genotyping study was carried out using DNA from SIDS parents (n = 10), control donors (n = 10) and Bangladeshi subjects (n = 10). An IFN polymorphism (3/3) was found in 40%, 15.4% and 0% of donors respectively. Staphylococcal toxins have been identified in SIDS infants therefore this study highlights the importance of assessing IL‐1 levels. Determination of cytokine polymorphisms and consideration of interactions between these and environmental factors such as smoking in high, average and low risk ethnic groups will assist in establishing the contribution of these factors to an infant's susceptibility to SIDS.
Child sexual abuse treatment: misinterpretation and mismanagement of child sexual behaviour
Authors: Kools S. , Kennedy C. 
Published: March 2003

AbstractObjective The purpose of the study was to examine caregiver understanding of the impact of child sexual abuse and the management of abused children in residential treatment.Methods A purposive sample of 20 registered nurses and child care workers were interviewed about their experiences working in residential treatment and their knowledge about child development and child sexual abuse and its application to practice. Data from interviews and field notes were analysed using dimensional analysis.Findings Caregivers had limited knowledge of the sequelae of child sexual abuse. Developmentally appropriate behaviour of sexually abused children, as well as behavioural manifestations of child sexual abuse, were often misinterpreted and mismanaged.Conclusion Residential care of sexually abused children should be based on sound developmental principles and caregiver sensitivity.
Nightmares and anxiety in elementary‐aged children: is there a relationship?
Authors: Mindell J. A. , Barrett K. M. 
Published: March 2003

AbstractObjective To determine whether a relationship exists between children’s anxiety level and nightmare occurrence.Method A total of 60 kindergarten, second and fourth grade school children and their parents completed questionnaires assessing nightmare occurrence and anxiety.Results According to parental report, children who experience nightmares have significantly higher levels of anxiety than children who do not experience nightmares. The results also indicate a relationship between nightmare distress and trait anxiety.Conclusion These findings suggest that anxiety issues should be considered in children who are experiencing nightmares.