bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correspondence of In Vitro and In Vivo Fluconazole Dose-Response Curves for
Cryptococcus neoformans
Authors: Larsen Robert A. , Bauer Madeline , Thomas Ann M. , Sanchez Alejandro , Citron Diane , Rathbun Meri , Harrison Thomas S. 
Published: July 2005

ABSTRACT

We conducted in vitro experiments to evaluate the susceptibility of a clinical isolate of
Cryptococcus neoformans
to a wide range of concentrations of fluconazole. In vitro susceptibility was tested using broth macrodilution methods modified to provide a numeric count of viable organisms. The association between the quantitative in vitro response and fluconazole drug concentrations was estimated using local nonparametric regression. Regression analysis was used to assess the correspondence between the in vitro fluconazole concentration-response curve and the murine dose-response curve observed in our previously reported murine model. The regression model was then used to predict the murine response. There was a strong correspondence between in vitro measures of response to fluconazole alone and the previously reported biologic effects seen in the mouse. In vitro antifungal drug susceptibility testing can reliably predict the murine response to fluconazole.
Bactericidal and Morphological Effects of NE-2001, a Novel Synthetic Agent Directed against
Helicobacter pylori
Authors: Dai Guofei , Cheng Ni , Dong Lei , Muramatsu Mutsumi , Xiao Shudong , Wang Ming-Wei , Zhu De-Xu 
Published: July 2005

ABSTRACT

The antibacterial activities of NE-2001 were tested against 24 clinical isolates of
Helicobacter pylori
and compared with those of amoxicillin, clarithromycin, metronidazole, and furazolidone. The MIC
50
and MIC
90
of this synthetic compound on the isolates were 8 and 16 μg/ml, respectively. This action was highly selective against
Helicobacter pylori
; there was a >4-fold difference between the concentration of NE-2001 required to inhibit the growth of
Helicobacter pylori
and that required to inhibit the growth of common aerobic and anaerobic bacteria. Exposure of
Helicobacter pylori
(ATCC43504) to NE-2001 at the MIC (4 μg/ml), or at a greater concentration, resulted in an extensive loss of viability. The phenomenon was also observed at pH levels between 3.0 and 7.0. When two clinical
Helicobacter pylori
strains were successively cultured at subinhibitory concentrations of NE-2001, no significant changes in the bactericidal effects were found. The morphological alterations of
Helicobacter pylori
cells (ATCC43504), exposed to NE-2001 at various concentrations for 6 h, were observed using transmission electron microcopy. The bacterium displayed features such as swelling, vacuole-like structures in the cytoplasm, and cell destruction following exposure to NE-2001. The efficacy of NE-2001 was maintained when evaluated in eight clinical isolates resistant to metronidazole and five isolates resistant to both metronidazole and clarithromycin (MIC ranging between 4 and 16 μg/ml). The above-described results suggest that NE-2001 may have the potential to be developed as a candidate agent for the treatment of
Helicobacter pylori
infection.
Effect of Antibiotic Treatment on Growth of and Toxin Production by
Clostridium difficile
in the Cecal Contents of Mice
Authors: Pultz Nicole J. , Donskey Curtis J. 
Published: July 2005

ABSTRACT

In mice, subcutaneous administration of antibiotics that disrupt the anaerobic microflora (i.e., clindamycin, piperacillin-tazobactam, and ceftriaxone) facilitated in vitro growth of and toxin production by
Clostridium difficile
in cecal contents, whereas antibiotics that cause minimal disruption of the anaerobic microflora (i.e., levofloxacin, cefepime, and aztreonam) did not.
Effect of Various Antibacterial Preparations on the Pathogenic Oral Flora in Elderly Patients Fed via Nasogastric Tube
Authors: Leibovitz Arthur , Carmeli Yehuda , Segal Refael 
Published: July 2005

ABSTRACT

Oropharyngeal colonization by pathogenic gram-negative bacilli (GNB) and
Staphylococcus aureus
is associated with aspiration pneumonia. Decolonization in high-risk populations may be important. We prospectively evaluated six antiseptic compounds in nasogastric tube-fed frail elderly patients; only polymixine reduced oropharyngeal colonization with GNB. None had an effect on
S. aureus
colonization.
Prevalence of Resistance Mechanisms against Macrolides and Lincosamides in Methicillin-Resistant Coagulase-Negative Staphylococci in the Czech Republic and Occurrence of an Undefined Mechanism of Resistance to Lincosamides
Authors: Novotna Gabriela , Adamkova Václava , Janata Jiri , Melter Oto , Spizek Jaroslav 
Published: July 2005

ABSTRACT

High occurrence of the non-macrolide-lincosamide-streptogramin B resistance genes
msrA
(53%) and
linA
/
linA
′ (30%) was found among 98 methicillin-resistant coagulase-negative staphylococci additionally resistant to macrolides and/or lincosamides. The gene
msrA
predominated in
Staphylococcus haemolyticus
(43 of 62 isolates). In
Staphylococcus epidermidis
, it was present in 7 of 27 isolates. A novel mechanism of resistance to lincosamides appears to be present in 10 genetically related isolates of
S. haemolyticus
in the absence of
ermA
,
ermC
,
msrA
, and
linA
/
linA
′.
Coordinated Replication and Sequestration of
oriC
and
dnaA
Are Required for Maintaining Controlled Once-per-Cell-Cycle Initiation in
Escherichia coli
Authors: Riber Leise , Løbner-Olesen Anders 
Published: August 2005

ABSTRACT

Escherichia coli
cells were constructed in which the
dnaA
gene was moved to a location opposite
oriC
on the circular chromosome. In these cells the
dnaA
gene was replicated with significant delay relative to the origin. Consequently, the period where the newly replicated and hemimethylated
oriC
was sequestered no longer coincided with the period where the
dnaA
gene promoter was sequestered. DnaA protein synthesis was therefore expected to continue during origin sequestration. Despite a normal length of the sequestration period in such cells, they had increased origin content and also displayed asynchrony of initiation. This indicated that reinitiation occasionally occurred at some origins within the same cell cycle. The extra initiations took place in spite of a reduction in total DnaA protein concentration to about half of the wild-type level. We propose that this more efficient utilization of DnaA protein results from an increased availability at the end of the origin sequestration period. Therefore, coordinated sequestration of
oriC
and
dnaA
is required for maintaining controlled once-per-cell-cycle initiation.
Molecular Characterization of a Widespread, Pathogenic, and Antibiotic Resistance-Receptive
Enterococcus faecalis
Lineage and Dissemination of Its Putative Pathogenicity Island
Authors: Nallapareddy Sreedhar R. , Wenxiang Huang , Weinstock George M. , Murray Barbara E. 
Published: August 2005

ABSTRACT

Enterococcus faecalis
, a common cause of endocarditis and known for its capacity to transfer antibiotic resistance to other pathogens, has recently emerged as an important, multidrug-resistant nosocomial pathogen. However, knowledge of its lineages and the potential of particular clones of this species to disseminate and cause disease is limited. Using a nine-gene multilocus sequence typing (MLST) scheme, we identified an evolving and widespread clonal complex of
E. faecalis
that has caused outbreaks and life-threatening infections. Moreover, this unusual clonal complex was found to contain isolates of unexpected relatedness, including the first known U.S. vancomycin-resistant enterococcus (
E. faecalis
strain V583), the first known penicillinase-producing (Bla
+
)
E. faecalis
isolate, and the previously described widespread clone of penicillinase producers, a trait found in <0.1% of
E. faecalis
isolates. All members of this clonal cluster (designated as BVE for Bla
+
Van
r
endocarditis) were found to contain a previously described putative pathogenicity island (PAI). Further analysis of this PAI demonstrated its dissemination worldwide, albeit with considerable variability, confirmed its association with clinical isolates, and found a common insertion site in different clonal lineages. PAI deletions, MLST, and the uncommon resistances were used to predict the evolution of the BVE clonal cluster. The finding of a virulent and highly successful clonal complex of
E. faecalis
with different members resistant to the primary therapies of choice, ampicillin and vancomycin, has important implications for the evolution of virulence and successful lineages and for public health monitoring and control.
The
Escherichia coli
CpxA-CpxR Envelope Stress Response System Regulates Expression of the Porins OmpF and OmpC
Authors: Batchelor Eric , Walthers Don , Kenney Linda J. , Goulian Mark 
Published: August 2005

ABSTRACT

We performed transposon mutagenesis of a two-color fluorescent reporter strain to identify new regulators of the porin genes
ompF
and
ompC
in
Escherichia coli
. Screening of colonies by fluorescence microscopy revealed numerous mutants that exhibited interesting patterns of porin expression. One mutant harbored an insertion in the gene encoding the histidine kinase CpxA, the sensor for a two-component signaling system that responds to envelope stress. The
cpxA
mutant exhibited increased transcription of
ompC
and a very strong decrease in transcription of
ompF
under conditions in which acetyl phosphate levels were high. Subsequent genetic analysis revealed that this phenotype is dependent on phosphorylation of the response regulator CpxR and that activation of CpxA in wild-type cells results in similar regulation of porin expression. Using DNase I footprinting, we demonstrated that CpxR binds upstream of both the
ompF
and
ompC
promoters. It thus appears that two distinct two-component systems, CpxA-CpxR and EnvZ-OmpR, converge at the porin promoters. Within the context of envelope stress, outer membrane beta-barrel proteins have generally been associated with the sigma E pathway. However, at least for the classical porins OmpF and OmpC, our results show that the Cpx envelope stress response system plays a role in regulating their expression.
Carboxyl-Terminal Protease RegulatesBrucella suisMorphology in Culture and Persistence in Macrophages and Mice
Authors: Bandara Aloka B. , Sriranganathan Nammalwar , Schurig Gerhardt G. , Boyle Stephen M. 
Published: August 2005

ABSTRACTThe putative carboxyl-terminal processing protease (CtpA) ofBrucella suis1330 is a member of a novel family of endoproteases involved in the maturation of proteins destined for the cell envelope. TheB. suisCtpA protein shared up to 77% homology with CtpA proteins of other bacteria. A CtpA-deficientBrucellastrain (1330ΔctpA), generated by allelic exchange, produced smaller colonies on enriched agar plates and exhibited a 50% decrease in growth rate in enriched liquid medium and no growth in salt-free enriched medium compared to the wild-type strain 1330 or thectpA-complemented strain 1330ΔctpA[pBBctpA]. Electron microscopy revealed that in contrast to the native coccobacillus shape of wild-type strain 1330, strain 1330ΔctpApossessed a spherical shape, an increased cell diameter, and cell membranes partially dissociated from the cell envelope. In the J774 mouse macrophage cell line, 24 h after infection, the CFU of the strain 1330ΔctpAdeclined by approximately 3 log10CFU relative to wild-type strain 1330. Nine weeks after intraperitoneal inoculation of BALB/c mice, strain 1330ΔctpAhad cleared from spleens but strain 1330 was still present. These observations suggest that the CtpA activity is necessary for the intracellular survival ofB. suis. Relative to the saline-injected mice, strain 1330ΔctpA-vaccinated mice exhibited 4 to 5 log10CFU of protection against challenge with virulentB. abortusstrain 2308 orB. suisstrain 1330 but no protection againstB. melitensisstrain 16 M. This is the first report correlating a CtpA deficiency with cell morphology and attenuation ofB. suis.
Analysis of the Role of RsbV, RsbW, and RsbY in Regulating σ
B
Activity in
Bacillus cereus
Authors: van Schaik Willem , Tempelaars Marcel H. , Zwietering Marcel H. , de Vos Willem M. , Abee Tjakko 
Published: August 2005

ABSTRACT

The alternative sigma factor σ
B
is an important regulator of the stress response of
Bacillus cereus
. Here, the role of the regulatory proteins RsbV, RsbW, and RsbY in regulating σ
B
activity in
B. cereus
is analyzed. Functional characterization of RsbV and RsbW showed that they act as an anti-sigma factor antagonist and an anti-sigma factor, respectively. RsbW can also act as a kinase on RsbV. These data are in line with earlier functional characterizations of RsbV and RsbW homologs in
B. subtilis
. The
rsbY
gene is unique to
B. cereus
and its closest relatives and is predicted to encode a protein with an N-terminal CheY domain and a C-terminal PP2C domain. In an
rsbY
deletion mutant, the σ
B
response upon stress exposure was almost completely abolished, but the response could be restored by complementation with full-length
rsbY
. Expression analysis showed that
rsbY
is transcribed from both a σ
A
-dependent promoter and a σ
B
-dependent promoter. The central role of RsbY in regulating the activity of σ
B
indicates that in
B. cereus
, the σ
B
activation pathway is markedly different from that in other gram-positive bacteria.
The we and the us
Authors: Crawford Kijana , Smith Danielle 
Published: July 2005

This study investigates the importance of mentoring in African American women’s selection of higher education as a career choice and in their development as professionals in that career. The research provides recommendations on how African American female administrators in higher education can further advance their career choices and career development. Mentoring has been identified as a factor leading to upward mobility in employment, success in education, and personal development. However, research to date has not addressed the following questions: • How are mentors relevant to the career choices and development of African American women administrators in higher education? • How do race and gender affect the career decision-making process of African American women in higher education? This research clarifies how mentoring affects the career choices of African American women who become administrators in higher education and how their sociocultural and gender experiences define their career choices and development.
Collaborative alliances: the environment, women and the Africa 2000 Network
Authors: Muteshi Jacinta Khasiala 
Published: August 2005

This paper reviews the work of an international environmental management project known as the Africa 2000 Network that emerged from the need to address the growing awareness of gender issues in environmentally sustainabledevelopment activities worldwide. The intention of this study was first to establish the degree of linkage between women’s needs and interests and the work of Africa 2000 Network’s national coordinators in Cameroon, Ghana, and Kenya. The second was to relate the findings of Africa 2000 Network’s (hereafter called the Network) responses to women to the current research on gender, environment and development. The third was to clarify more specifically and substantively the types of actions that have empowered the resource management roles of African women while at the same time alleviating the effects of environmental degradation. It is hoped that this investigation will begin to contribute to the formulation of strategies and structures that go beyond the mere cooptation of African women’s labour into mainstream development activities. The aim is to work towards the transformation of current configurations of power relations within the ownership and control of resources; not only between men and women but also, ultimately, between nations.
Reducing risk as a tool for urban improvement: the Caqueta ravine, Lima, Peru
Authors: Sanderson David 
Published: August 2005

This paper presents a description of the Caqueta district in Lima and describes the methodology and research methods used. It presents the key findings of the project and concludes with a brief discussion of mitigation as a tool for urban development. The paper seeks to reinforce the key point of the project: that adherence to “top down” interventions can ignore community level initiatives and the positive inputs of other actors; also that risk reduction can be used as a tool in uniting key actors to focus on protecting livelihoods, as well as lives, in the promotion of sustainable urban development. This paper results from a recently completed project entitled “Reducing Risk In Vulnerable Communities, Lima, Peru. Phase One: Caqueta Pilot Project”. The principle aim of the project was to identify and subsequently develop, with the participation of key “stakeholders”, sustainable risk reduction measures for Caqueta, a particularly low-income area of Lima, Peru, vulnerable to landslides, earthquakes and fire.
Novel lentiviral vectors displaying “early-acting cytokines” selectively promote survival and transduction of NOD/SCID repopulating human hematopoietic stem cells
Authors: Verhoeyen Els , Wiznerowicz Maciej , Olivier Delphine , Izac Brigitte , Trono Didier , Dubart-Kupperschmitt Anne , Cosset François-Loïc 
Published: August 2005

AbstractA major limitation of current lentiviral vectors (LVs) is their inability to govern efficient gene transfer into quiescent cells, such as human CD34+ cells, that reside in the G0 phase of the cell cycle and that are highly enriched in hematopoietic stem cells. This hampers their application for gene therapy of hematopoietic cells. Here, we designed novel LVs that overcome this restriction by displaying “early-acting cytokines” on their surface. Display of thrombopoietin, stem cell factor, or both cytokines on the LV surface allowed efficient gene delivery into quiescent cord blood CD34+ cells. Moreover, these surface-engineered LVs preferentially transduced and promoted survival of resting CD34+ cells rather than cycling cells. Finally, and most importantly, these novel LVs allowed superior gene transfer in the most immature CD34+ cells as compared to conventional LVs, even when the latter vectors were used to transduce cells in the presence of recombinant cytokines. This was demonstrated by their capacity to promote selective transduction of CD34+ cell in in vitro derived long-term culture-initiating cell (LTC-IC) colonies and of long-term NOD/SCID repopulating cells (SRCs) in vivo.
Service needs of parents with motor or multiply disabled children in Dutch therapeutic toddler classes
Authors: Hendriks Alexander HC , De Moor Jan MH , Oud Johan HL , Franken Waltera M 
Published: August 2005

Objective: To determine parents' service needs at the start of therapeutic toddler class treatment, to analyse determinants and to investigate received help after a period of 10 months. Subjects: Parents with motor or multiply disabled children in therapeutic toddler classes. Setting: Sixteen out of 17 Dutch rehabilitation centres. Design: A sample of 84 parents, stratified according to toddler class size. Main outcome measures: A questionnaire of 33 items, divided into five categories, was designed to assess parents' needs and to evaluate the amount of received help. Several measures were used to assess child, parent and family characteristics. Results: Based on factor analysis, five need subscales were distinguished which only partially corresponded to the initial categories. The initial category concerning needs for help in family functioning did not come out as a factor. Needs expressed most frequently belonged to the three subscales of needs for information concerning the child. The average level of needs generally did not differ for mothers and fathers across the subscales. However, we found large variation in needs for both mothers and fathers on each subscale. The most important, positively correlated determinant of parents' needs was social isolation of the family. After 10 months a considerable level of unmet needs was found. Conclusions: A systematic and periodic assessment of individual needs of parents as well as the services offered is recommended. Professionals of the therapeutic toddler classes should especially focus on providing parents with information on their child's disability and therapy, community services and parenting.
Can young severely disabled stroke patients regain the ability to walk independently more than three months post stroke?
Authors: Jackson Diana , Thornton Heather , Turner-Stokes Lynne 
Published: August 2005

Objective: To investigate the acquisition of ability to walk independently in young severely disabled stroke patients unable to walk three months after onset. Setting: A regional rehabilitation unit providing post-acute neurorehabilitation mainly for patients aged 16–65 years. Subjects and methods: A retrospective analysis of records was undertaken for 152 stroke patients admitted consecutively over a three-year period. All had a combination of physical, cognitive and language impairments; male/female 98/54; median age 54 (IQR 47–60) years. Main outcome measures: Time taken from stroke onset to regain the ability to walk safely and independently at least 5 metres around the hospital bay. Results: Seventy-five (49%) regained the ability to walk independently between 3 and 11 months post onset. Patients with cognitive impairments and neglect took longer to walk. Time from stroke onset to admission was longer in patients who did not walk (median 16.3 weeks), than in those who regained walking (median 12.7 weeks; p = 0.009). Independent positive associations were found between the time taken to walk and time from onset to referral for rehabilitation (= 0.55; p < 0.001), and time from acceptance to admission (= 0.30; p = 0.008). Conclusion: With intensive specialist input, significant numbers of severely disabled young stroke patients can regain independent walking many months after onset, though late walkers may follow a slower recovery course. These results argue for investment in appropriate rehabilitation for these patients. Waiting list delays may prolong rehabilitation and potentially compromise cost effectiveness.
Reliability of lower extremity isokinetic strength testing in adults with stroke
Authors: Pohl Patricia S , Startzell Jill K , Duncan Pamela W , Wallace Dennis 
Published: August 2005

Objective: To evaluate the reliability of isokinetic strength testing of knee flexion and extension at 60 degrees per second, and ankle plantar flexion and dorsiflexion at 30 degrees per second in adults with stroke. Design: Test–retest using intraclass correlation coefficients (ICC). Setting: Human performance laboratory. Subjects: Ten adults post stroke with a mean age of 64 years (five males) and 10 adults without neurological injury with a mean age of 69 years (three males) who served as controls. Main outcome measures: Peak torque and average torque. Results: The reliability of strength of the less-affected lower extremity was high with values ranging from 0.75 to 0.97. Knee extension, ankle plantar flexion and the peak torque of dorsiflexion were reliable for the affected limb, ranging from 0.80 to 0.90. In contrast, affected knee flexion was not reliable with values of 0.48 and 0.44 for peak torque and average peak torque respectively. Conclusions: Isokinetic knee and ankle strength of the less-affected limb are reliable. Isokinetic strength of the affected lower extremity is also reliable with the noted exception of knee flexion.