bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antibiotic Inducibility of the MexXY Multidrug Efflux System of
Pseudomonas aeruginosa
: Involvement of the Antibiotic-Inducible PA5471 Gene Product
Authors: Morita Yuji , Sobel Mara L. , Poole Keith 
Published: February 2006

ABSTRACT

The MexXY components of the MexXY-OprM multidrug efflux system of
Pseudomonas aeruginosa
are encoded by a MexZ repressor-regulated operon that is inducible by antibiotics that target the ribosome. Mutant strains disrupted in a gene, PA5471, were shown to be compromised for drug-inducible
mexXY
expression and, therefore, MexXY-OprM-mediated antimicrobial resistance. The PA5471 gene was inducible by the same ribosome-targeting agents that induce
mexXY
expression. Moreover, vector-driven expression of cloned PA5471 was sufficient to promote
mexXY
expression and MexXY-mediated resistance in the absence of antibiotic exposure, consistent with PA5471 directly or indirectly activating
mexXY
expression following its own upregulation in response to antibiotics. The requirement for PA5471 for
mexXY
expression and antimicrobial resistance was, however, obviated in mutants lacking the MexZ repressor of
mexXY
expression, suggesting that PA5471 directly or indirectly modulates MexZ activity in effecting
mexXY
expression. While the recruitment of PA5471 and MexXY in response to ribosome disruption by antimicrobials is consistent with their genes playing a role in protecting cells from the adverse consequences of disrupting the translation process, reminiscent of
trans
-translation, these genes appear to operate independently in their contribution to resistance: mutants defective in
trans
-translation showed a much more modest (twofold) decrease in resistance to ribosome-targeting agents than those lacking PA5471 or MexXY, and this decrease was observed whether functional PA5471/MexXY was present or not.
Overexpression of
tnaC
of
Escherichia coli
Inhibits Growth by Depleting tRNA
2
Pro
Availability
Authors: Gong Ming , Gong Feng , Yanofsky Charles 
Published: February 2006

ABSTRACT

Transcription of the tryptophanase (
tna
) operon of
Escherichia coli
is regulated by catabolite repression and tryptophan-induced transcription antitermination. Induction results from ribosome stalling after translation of
tnaC
, the coding region for a 24-residue leader peptide. The last sense codon of
tnaC
, proline codon 24 (CCU), is translated by tRNA
2
Pro
. We analyzed the consequences of overexpression of
tnaC
from a multicopy plasmid and observed that under inducing conditions more than 60% of the tRNA
2
Pro
in the cell was sequestered in ribosomes as TnaC-tRNA
2
Pro
. The half-life of this TnaC-tRNA
2
Pro
was shown to be 10 to 15 min under these conditions. Plasmid-mediated overexpression of
tnaC
, under inducing conditions, reduced cell growth rate appreciably. Increasing the tRNA
2
Pro
level relieved this growth inhibition, suggesting that depletion of this tRNA was primarily responsible for the growth rate reduction. Growth inhibition was not relieved by overexpression of tRNA
1
Pro
, a tRNA
Pro
that translates CCG, but not CCU. Replacing the Pro24CCU codon of
tnaC
by Pro24CCG, a Pro codon translated by tRNA
1
Pro
, also led to growth rate reduction, and this reduction was relieved by overexpression of tRNA
1
Pro
. These findings establish that the growth inhibition caused by
tnaC
overexpression during induction by tryptophan is primarily a consequence of tRNA
Pro
depletion, resulting from TnaC-tRNA
Pro
retention within stalled, translating ribosomes.
Borrelia burgdorferi ftsZ
Plays a Role in Cell Division
Authors: Dubytska Lydia , Godfrey Henry P. , Cabello Felipe C. 
Published: February 2006

ABSTRACT

ftsZ
is essential for cell division in many microorganisms. In
Escherichia coli
and
Bacillus subtilis
, FtsZ plays a role in ring formation at the leading edge of the cell division septum. An
ftsZ
homologue is present in the
Borrelia burgdorferi
genome (

ftsZ
Bbu

). Its gene product (FtsZ
Bbu
) is strongly homologous to other bacterial FtsZ proteins, but its function has not been established. Because loss-of-function mutants of

ftsZ
Bbu

might be lethal, the
tetR/tetO
system was adapted for regulated control of this gene in
B. burgdorferi
. Sixty-two nucleotides of an

ftsZ
Bbu

antisense DNA sequence under the control of a tetracycline-responsive modified hybrid borrelial promoter were cloned into pKFSS1. This construct was electroporated into a
B. burgdorferi
host strain carrying a chromosomally located
tetR
under the control of the
B. burgdorferi flaB
promoter. After induction by anhydrotetracycline, expression of antisense
ftsZ
RNA resulted in generation of filamentous
B. burgdorferi
that were unable to divide and grew more slowly than uninduced cells. To determine whether FtsZ
Bbu
could interfere with the function of
E. coli
FtsZ,

ftsZ
Bbu

was amplified from chromosomal DNA and placed under the control of the tetracycline-regulated hybrid promoter. After introduction of the construct into
E. coli
and induction with anhydrotetracycline, overexpression of

ftsZ
Bbu

generated a filamentous phenotype. This suggested interference of

ftsZ
Bbu

with
E. coli
FtsZ function and confirmed the role of

ftsZ
Bbu

in cell division. This is the first report of the generation of a
B. burgdorferi
conditional lethal mutant equivalent by tetracycline-controlled expression of antisense RNA.
Religious Bricolage as a Psychological Reality: Limits, Structures and Dynamics
Authors: Saroglou Vassilis 
Published: February 2006

English The contemporary proliferation in sociology of religion of terms such as “religious bricolage” or “religion à la carte” as reflecting clear tendencies in modern religious and spiritual expressions leaves the psychologist of religion somewhat perplexed. Although no empirical studies of such phenomena exist from a psychological perspective, related theory and research from other psychological domains can provide material that allows us to question the extent and depth of the reality of the so-called “religious bricolage”. This will be the main point of the present article. In addition, we will emphasize the need to go beyond descriptive case studies and look for general structures and “laws” capable of explaining the rationale and the dynamics (e.g. cognitive, emotional, and motivational) of this phenomenon, at least, as the latter appears today in Western countries. French La prolifération en sociologie de la religion de termes tels que "bricolage religieux'' ou "religion à la carte'', censés refléter des tendances claires des expressions religieuses et spirituelles modernes, laisse le psychologue de la religion quelque peu perplexe. Bien qu'il n'existe pas d'études empiriques de ce phénomè ne effectuées dans une perspective psychologique, le recours à certaines théories et aux résultats d'études menées dans d'autres domaines psychologiques connexes permettraient de mieux appréhender l'étendue et la profondeur de la réalité du dit "bricolage religieux''. Ce sera le but de cet article. En outre, l'auteur met l'accent sur la nécessité d'aller au-delà des études de cas descriptives et de chercher des structures générales et des "lois'' capables d'expliquer la logique et les dynamiques-cognitives, émotionnelles et motivationnelles-de ce phénomène, du moins tel qu'il apparaît aujourd'hui dans les pays occidentaux.
Prevalence of STI/HIV co-infections among special treatment clinic attendees in Ibadan, Nigeria
Authors: Kehinde Aderemi O , Lawoyin Taiwo O 
Published: February 2006

Sexually transmitted infections (STIs) are poorly recognised and inadequately treated in Nigeria despite the fact that they constitute a major risk factor for sexual transmission of HIV infection. This study was carried out to ascertain STI/HIV co-infection rates and also to obtain relevant socio-demographic and reproductive health data associated with STI/HIV infections among special treatment clinic (STC) attendees. This information is urgently needed for designing STI/HIV control strategies. All consenting patients who attended the STC clinic from March to November 2001 were interviewed to obtain their socio-demographic and reproductive health data. Urethral, high vaginal and endocervical swabs and urine specimens were obtained and processed by standard methods. HIV screening was done by double ELISA tests. Of the 210 patients seen, 98 (46.7%) were male and 112 (53.3%) were female (p>0.05). The majority, 171 (81.4%) were aged 20-39 years, while only ten (4.8%) were adolescents. One-hundred-and-eighty (85.7%) had an STI, of which 41 (22.8%) were co-infected with HIV. Thirty (16.7%) patients with nongonococcal urethritis/cervicitis and five (2.8%) with gonorrhoea were also positive for HIV. Five patients were HIV positive but had no other STI. Patients with gonorrhoea, non-gonococcal urethritis/cervicitis, trichomoniasis and bacterial vaginosis were more likely than those with warts, candidiasis and herpes to have co-infection (X2=12.5, p=0.04). The studyís HIV prevalence rate was 21.9%. STI/HIV co-infection rate was significantly higher among unskilled and unemployed patients compared with professional and skilled workers (p<0.05). This study shows a high STI/HIV co-infection rate indicating that there is need for proper management of STI, as this will help curb the spread of HIV infection in Nigeria.
Health promotion in pregnancy: the role of the midwife
Authors: Beldon Annemarie , Crozier Suzanne 
Published: February 2006

Health promotion is of particular importance to midwives who promote health rather than manage disease and ill health. Although the midwife has always had a role in public health, there is now an explicit need for the profession to direct its attention to teenage pregnancy, smoking cessation, drug awareness and domestic violence. Much of the role of the midwife during pregnancy is in health promotion and a more explicit application of such may carry benefits in meeting Government policy on public health. Some activities undertaken by midwives may not be identified as health promotion, though there is evidence that the interaction generated by routine examinations is of benefit to the motherís health. Midwives should work in partnership with women and families, facilitating decisions about the care that they feel they may require. Social disadvantage may impede participation where formal education was not valued or ethnic background or language impaired access to traditional childbirth education. Tackling this is at the heart of current public health policy around childbirth and child care. Education can take place during any interaction and this gives midwives huge scope to provide an educational experience for women each time they meet. For the pregnant teenager the extended family may need to be included in health promotion activities particularly if breastfeeding targets are to be met. A united health and education policy to inform and educate children and teenagers about the benefits of pre-conceptional care and breastfeeding may be needed. In this way young women come into contact with midwives before they are pregnant, before attitudes to breastfeeding are established and before the concept of pre-conceptional care is lost. Although breastfeeding improves health for women and their infants it can become another burden and expectation which they fail to achieve. Professionals need to be sensitive to the possible negative impact on a womanís health, which could be reduced if the emphasis was moved from individual behaviour change to the inequalities within society. Midwives should seek to respond positively to service changes to achieve the goal of multidisciplinary, non-hierarchical patient-centred services. In facilitating change midwives seek to use their influence to the benefit of the pregnant woman.
Factors influencing antenatal and postnatal diets of primigravid women
Authors: Tuffery Olga , Scriven Angela 
Published: February 2006

This article disseminates research on the self-reported perceived factors influencing antenatal and postnatal diets of a sample of primigravid women. Participants (n=39) were recruited from general medical practices during the first trimester of pregnancy, with 37 participants remaining in the study until six months post-partum. Self-reported diet diaries at the first trimester, third trimester and six months post-partum generated information on food consumption, using estimated portions. In-depth interviews at the same three time points identified environmental, physical, social and emotional barriers to healthy eating during pregnancy. Findings from the interviews indicate that the key influences on dietary choices change over the three time periods. Conclusions relate to the key influencing factors and a number of recommendations are made for health promotion interventions to ensure women are informed and able to choose a healthy eating plan during pregnancy and post-partum.
The nutritional status of women in the first trimester of pregnancy attending an inner-city antenatal department in the UK
Authors: Rees Gail , Brooke Zoe , Doyle Wendy , Costeloe Kate 
Published: February 2006

We have previously found high rates of poor iron and folate status in women who had delivered a low birthweight baby (LBW) in an ethnically diverse inner-city area of the UK. However, little was known of the nutritional status in the local general obstetric population. We therefore investigated biochemical measures of nutritional status in the first trimester of the first pregnancy. Routine blood samples collected at the antenatal booking clinic were analysed for haemoglobin (Hb), serum ferritin, red cell folate (RCF) (n=100) and erythrocyte transketolase activation coefficient (ETKAC) for thiamin status (n=90). We found 9% of women in our sample had a low Hb level, 10% had a low serum ferritin and only one had a low RCF. This is a substantially lower number of women with biochemical deficiencies than we found previously in women three months after delivering a LBW baby. However, 34% had low thiamin status. Thiamin status was negatively correlated with gestational age at birth (r=-0.407, p<0.001). Differences in nutritional status were observed between ethnic and socio-economic groups. Hb levels differed between ethnic (p=0.001) and socio-economic groups (p=0.02), with Africans and women in manual occupations/unwaged having the lowest Hb levels. RCF levels also differed between groups (p<0.001) with Caucasians and those in non-manual occupations having highest levels. ETKAC also differed between ethnic groups (p=0.008) with Africans having the highest level indicating a poorer status. The study highlights the need to improve nutrition particularly in ethnic minorities and low income groups who are most at risk of adverse birth outcomes such as LBW.
Periodontitis and pregnancy
Authors: Tucker Richard 
Published: February 2006

There is an increasing amount of evidence suggesting a systemic link between periodontal disease in the pregnant mother and pre-term low birth weight (PLBW). Severe periodontitis affects at least 10% of the general population. The aetiology of periodontitis is essentially a bacterially induced inflammatory reaction within the attachment surrounding the teeth. Maternal infection has been linked with pre-term delivery. Normal pregnancy itself is associated with inflammatory changes very similar to those found in sepsis. Because the infected periodontal tissues can act as a reservoir for both bacterial products and inflammatory cytokines, it may be possible that periodontal infection and the resultant inflammation could be linked with PLBW. Current understanding suggests that prostaglandins and proinflammatory cytokines play a pivotal role in the initiation process because of the close relationship of inflammation and infection. High levels of maternally or fetally derived cytokines such as tumour necrosis factor alpha (TNFa) may enhance amniochorionic and decidual interleukin six (IL-6) expression. Prostaglandin E2 (PGE2) has also been associated with periodontitis and PLBW. Periodontitis is a possible risk factor for PLBW with an odds ratio of 2.30. For the majority of individuals affected with periodontitis, the condition is symptom-free until the disease is more advanced. Therefore there is the need for medical carers of pregnant patients to increase the awareness among pregnant women themselves. Although there is plenty of evidence associating periodontitis with PLBW, interventional studies for the treatment of periodontitis measuring the impact on PLBW are few in number. Therefore more good quality clinical trials are required to address this issue.
Caregiver perspectives in oral healthcare in an institutionalised elderly population without access to dental services: a pilot study
Authors: Matear David W , Barbaro John 
Published: February 2006

Aim: The provision of dental services to elderly populations is a complicated area. When clients are cognitively impaired, a new set of variables are introduced as care can be influenced by designated family members, caregivers or administrators, who are responsible for the oral health care of the client and may influence the types of treatment the client will receive. Differences in attitudes and perceptions, with respect to oral health, may lead to better or worse access to care. The goals of this study are: a) to gain a better understanding of the perceptions which may govern access and barriers to care within the institutionalised elderly population; and b) to improve information on where and how to target educational and service resources, in order to reduce barriers to care. Method: A convenience (non-randomised) sample of 100 residents with caregivers was selected from nursing homes without organised access to oral healthcare services. A structured interview was conducted with 40 family members. Questions explored the importance and priorities of dental services for elderly people in institutions. Results: Services which family members deemed of highest importance were dentures (both to replace teeth and adjustments on existing dentures), pain relief, emergency dentistry, fillings, cleanings, check-ups, tooth removal and treatment for advanced gum disease. Services that family members felt were less important were complex restorations, cleaning instruction to caregivers and seniors, and services by a specialist. Services considered to be of least importance were root canal treatment and implants. The top service priorities identified by the sample of family members included: cleanings to prevent mouth disease; check-ups including X-rays; fillings; dentures to replace teeth; and dental treatment to relieve pain. Conclusion:This study found that family members and caregivers would like a basic dental service including check-ups and preventive care, with restorative, denture and surgical intervention when required.
Body mass index of Kuwaiti children aged 3–9 years: reference percentiles and curves
Authors: Al-Isa Abdulwahab Naser , Thalib Lukman 
Published: February 2006

Aim:The suitability of using the standards for body mass index (BMI), produced in the US by the National Center for Health Statistics, for assessing overweight and obesity among children in Kuwait and other Arabian Gulf countries has not been examined. These standards were obtained from better-nourished and genetically different populations to those found in Kuwait and in other Gulf region countries. The purpose of this study was to develop BMI reference percentiles and curves appropriate for children aged 3–9 in these countries. Method:Attempts were made to include all healthy Kuwaiti kindergarten and elementary education children in this study. The total sample was 113,013, comprising 55,053 males and 57,960 females. The children were measured for weight and height from which the BMI was calculated. Appropriate polynomial regression smoothing techniques were used to obtain the best-fitting percentile curves. Results:At percentiles = 25th, the BMI of boys exceeded that of girls. At the 50th percentile, boys' BMI was mostly higher than or equal to that of the girls except at age nine where it was lower. At the 75th percentile, the BMI of both genders was similar, with exceptions at age six and nine years. At the 85th and 95th percentiles, girls' BMI was consistently higher than males. At the lowest percentile, the BMI of US children was higher than Kuwaiti, Saudi (starting at six) and Iranian children. The BMI of Kuwaiti children at higher percentiles was higher than that of Saudi, Iranian (except at age < four years) and US children. Conclusion:BMI curves for Kuwaiti children follow almost the same pattern as their US counterparts but with noticeable variations especially at the lower and higher percentiles. This study may reflect that western standards may not be directly applicable to assess the level of BMI in Kuwait and possibly in the neighbouring Gulf countries, since they may overestimate the levels of overweight, obesity and underweight.
The Case of Secretary versus Principal Or The Recalcitrant Secretary
Authors: MacNeil Angus , Fossey Richard 
Published: February 2006

In this case, a principal arrives at a troubled school in mid-year to discover that the school secretary is exerting managerial powers usually reserved for the principal. When the principal tries to implement changes, the secretary is combative and resistant. This case provides students an opportunity to explore the dynamics between a school principal and the school's support staff and to discuss the important role that a school secretary plays in a school's operation and culture. The case is accompanied by a brief review of literature on the secretary's role in a school and can be used in courses on human resources management, the principalship, or educational administration.
Antigen-presenting property of mesenchymal stem cells occurs during a narrow window at low levels of interferon-γ
Authors: Chan Jennifer L. , Tang Katherine C. , Patel Anoop P. , Bonilla Larissa M. , Pierobon Nicola , Ponzio Nicholas M. , Rameshwar Pranela 
Published: February 2006

AbstractMesenchymal stem cells (MSCs) are mostly found around the vasculature system of the adult bone marrow (BM). They function as immune suppressors, express MHC-II, are phagocytic, and support T-cell cytotoxicity. We hypothesize that these contradictory properties of MSCs are important for BM homeostasis and occur partly through antigen presentation (antigen-presenting cells [APCs]) within a narrow window. Indeed, we have verified APC functions of MSCs to recall antigens, Candida albicans and Tetanus toxoid. The target cells have been identified to be CD4+ T cells. APC assays with IFNγ-knockdown MSCs and with anti–IFNγ receptor confirmed that MHC-II expression requires autocrine stimulation by IFNγ. During APC functions, as IFNγ levels become elevated, there was a concomitant decrease in MHC-II on MSCs. This observation was correlated with flow cytometry studies showing a gradual decrease in MHC-II expression as IFNγ levels were increased. The reduced levels of MHC-II correlated with losses in their allogeneic potential, as indicated in mixed lymphocyte reaction. In summary, endogenous and low levels of IFNγ are required for MHC-II expression on MSCs, and for APC functions. APC functions occur during a narrow window before IFNγ levels are increased. The study has implications for BM protection against infection and exacerbated inflammatory responses.