bluuebunny/crossref_metadata_2025_split huggingface dataset:
Solar Cooling Economic Considerations: Centralized Versus
Decentralized Options
Authors: García-Casals Xavier 
Published: April 2006

Abstract
In Spain, as in other Mediterranean and low-latitude countries, cooling loads of the same order of magnitude or even higher than heating loads coexist with high solar radiation resources. Cooling loads in most of these countries have, thus far, not been completely incorporated into the building sector energy demand because they arise after that DHW (domestic hot water) and heating loads have been satisfied and the living standard of the population reaches a given threshold. The increasing comfort demand in the cooling season from a population living in buildings that were developed without taking into account these considerations are bringing about a strong increase in the installation of domestic vapor compression air conditioning units, aimed to partially fulfil the thermal comfort demand in few rooms of these dwellings. This has a significant impact on the environment and the electricity distribution system, in a moment when strong environmental constraints are being imposed on the energy system to fulfil international agreements as the Kyoto protocol. Solar absorption cooling emerges as an interesting alternative to satisfy this growing energy demand for cooling applications with synergies with solar energy use for heating and DHW purposes. However, solar absorption cooling has been there already, for decades, without having a significant development, and still today presents some limitations that prevent its widespread application. Other solar cooling alternatives, such as the use of commercial vapor compression air conditioning equipment fed with electricity from centralized solar power plants could, in short, become available in these countries. In this paper, based on the experienced gained with the simulation of the most recent installations of absorption cooling installations in Spain, we perform a cost comparison between decentralized and centralized solar cooling options to give some insight into the development requirements and possibilities from both solar cooling options.
Polyamines Increase Antibiotic Susceptibility in
Pseudomonas aeruginosa
Authors: Kwon Dong H. , Lu Chung-Dar 
Published: April 2006

ABSTRACT

Pseudomonas aeruginosa
is an opportunistic human pathogen. Treatment is complicated by frequent acquired resistance to antipseudomonal therapies. Polyamines (cadaverine, putrescine, spermidine, and spermine) are ubiquitous polycationic compounds essential for all living organisms. In a dose-dependent manner, polyamines increased the susceptibility of
P. aeruginosa
to 14 β-lactam antibiotics, chloramphenicol, nalidixic acid, and trimethoprim as demonstrated by a reduction in MIC of up to 64-fold. This effect was partially antagonized (25 to 50%) by the presence of 10 mM of Mg
2+
or Ca
2+
. In contrast, the effects of the outer membrane permeabilizers, polymyxin B nonapeptide and EDTA, were completely abolished by 3 mM Mg
2+
or Ca
2+
. Changes on the outer membrane barrier by these compounds were assessed by activity measurements of periplasmic β-lactamase. The results showed that while EDTA and polymyxin B serve as outer membrane disorganizing agents as expected, exogenous spermidine and spermine did not exhibit any apparent effect on outer membrane permeability or rupture. In summary, these results strongly suggest that the increased antibiotic susceptibility by polyamines is exerted by a mechanism that differs from that of EDTA and polymyxin B. Polyamines might be potentially useful in antipseudomonal therapies by increasing the effectiveness of certain β-lactam antibiotics.
Cellular Accumulation and Activity of Quinolones in Ciprofloxacin-Resistant J774 Macrophages
Authors: Michot Jean-Michel , Heremans Marie F. , Caceres Nancy E. , Mingeot-Leclercq Marie-Paule , Tulkens Paul M. , Van Bambeke Françoise 
Published: April 2006

ABSTRACT

Ciprofloxacin is the substrate for a multidrug resistance-related protein (MRP)-like multidrug transporter in J774 mouse macrophages, which also modestly affects levofloxacin but only marginally affects garenoxacin and moxifloxacin (J.-M. Michot et al., Antimicrob. Agents Chemother.
49:
2429-2437, 2005). Two clones of ciprofloxacin-resistant cells were obtained by a stepwise increase in drug concentration (from 34 to 51 to 68 mg/liter) in the culture fluid. Compared to wild-type cells, ciprofloxacin-resistant cells showed (i) a markedly reduced ciprofloxacin accumulation (12% of control) and (ii) a two- to threefold lower sensitivity to the enhancing effect exerted by MRP-inhibitors (probenecid and MK571) on ciprofloxacin accumulation or by ciprofloxacin itself. ATP-depletion brought ciprofloxacin accumulation to similarly high levels in both wild-type and ciprofloxacin-resistant cells. Garenoxacin and moxifloxacin accumulation remained unaffected, and levofloxacin showed an intermediate behavior. DNA and protein synthesis were not impaired in ciprofloxacin-resistant cells for ciprofloxacin concentrations up to 100 mg/liter (∼85 and 55% inhibition, respectively, in wild-type cells). In
Listeria monocytogenes
-infected ciprofloxacin-resistant cells, 12-fold higher extracellular concentrations of ciprofloxacin were needed to show a bacteriostatic effect in comparison with wild-type cells. The data suggest that the resistance mechanism is mediated by an overexpression and/or increased activity of the MRP-like ciprofloxacin transporter expressed at a basal level in wild-type J774 macrophages, which modulates both the intracellular pharmacokinetics and activity of ciprofloxacin.
Preclinical Safety and Efficacy Assessments of Dendrimer-Based (SPL7013) Microbicide Gel Formulations in a Nonhuman Primate Model
Authors: Patton D. L. , Cosgrove Sweeney Y. T. , McCarthy T. D. , Hillier S. L. 
Published: April 2006

ABSTRACT

Three gel formulations (1%, 3%, and 5% [wt/wt]) of SPL7013, a dendrimer known to have antiviral (anti-human immunodeficiency virus and anti-herpes simplex virus) activities, completed a range of preclinical tests in the pigtailed macaque models for vaginally and rectally applied topical microbicide safety assessments. The vaginal safety profile of the 3% SPL7013 gel formulation was equal to that of the 1% formulation but was superior to that of the 5% formulation. The 3% SPL7013 gel was further evaluated for rectal safety and for antichlamydial efficacy with cervical challenge with
Chlamydia trachomatis
. This first-generation dendrimer-based product was shown to be safe to the vaginal and rectal microenvironments with repeated daily use. However, a single intravaginal application of the 3% (wt/wt) SPL7013 gel did not provide protection from the acquisition of cervical chlamydial infection.
Long-Term Multiple-Dose Pharmacokinetics of Human Monoclonal Antibodies (MAbs) against Human Immunodeficiency Virus Type 1 Envelope gp120 (MAb 2G12) and gp41 (MAbs 4E10 and 2F5)
Authors: Joos Beda , Trkola Alexandra , Kuster Herbert , Aceto Leonardo , Fischer Marek , Stiegler Gabriela , Armbruster Christine , Vcelar Brigitta , Katinger Hermann , Günthard Huldrych F. 
Published: April 2006

ABSTRACT

While certain antibodies directed against the human immunodeficiency virus (HIV) envelope have the potential to suppress virus replication in vitro, the impact of neutralizing antibodies in vivo remains unclear. In a recent proof-of-concept study, the broadly neutralizing monoclonal antibodies 2G12, 4E10, and 2F5 exhibited inhibitory activities in vivo, as exemplified by a delay of the viral rebound following the interruption of antiretroviral therapy. Unexpectedly, the antiviral effect seen was most prominently due to 2G12 activity. To further investigate whether differential HIV-inhibitory activity was due to different pharmacokinetic properties of the antibodies, we performed a formal pharmacokinetic analysis with 14 patients. Repeated infusions at high dose levels were well tolerated by the patients and did not elicit an endogenous immune response against the monoclonal antibodies. The pharmacokinetic parameters of all three antibodies correlated with each other. Mean estimates were 0.047, 0.035, and 0.044 liter/kg for the central volume of distribution of 2G12, 4E10, and 2F5, respectively, and 0.0018, 0.0058, and 0.0077 liter/kg · day for the systemic clearance of 2G12, 4E10, and 2F5, respectively. Monoclonal antibody 2G12 had a significantly longer elimination half-life (21.8 ± 7.2 days [
P
< 0.0001]) than monoclonal antibodies 4E10 (5.5 ± 2.2 days) and 2F5 (4.3 ± 1.1 days). The comprehensive pharmacokinetic data from this long-term multiple-dose phase II study were coherent with those from previous short-term phase I studies, as assessed by compartmental and noncompartmental techniques. The anti-HIV type 1 antibodies studied showed distribution and elimination kinetics similar to those seen for other human-like antibodies. Further studies examining tissue concentrations to explain the differential in vivo activity of the anti-gp120 antibody compared with those of the two anti-gp41 antibodies are warranted.
Novel Effects of Azithromycin on Tight Junction Proteins in Human Airway Epithelia
Authors: Asgrimsson Valthor , Gudjonsson Thorarinn , Gudmundsson Gudmundur Hrafn , Baldursson Olafur 
Published: April 2006

ABSTRACT
The macrolide antibiotic azithromycin improves lung function and prognosis among patients with cystic fibrosis or diffuse panbronchiolitis, independently of bacterial eradication. Anti-inflammatory effects have been implicated, but data from in vivo studies are scarce, and the link between abnormal electrolyte content in airway surface liquid and bronchial infections remains uncertain. In the present study, we treated human airway epithelia on filter supports with azithromycin and monitored transepithelial electrical resistance. We found that azithromycin increased transepithelial electrical resistance of airway epithelia in a dose-dependent manner. Immunocytochemistry and Western blotting showed that addition of azithromycin changed the locations of proteins in cell cultures and induced processing of the tight junction proteins claudin-1 and claudin-4, occludin, and junctional adhesion molecule-A. These effects were reversible, and no effect was seen when cells were treated with penicillin or erythromycin. The data indicate that azithromycin increases the transepithelial electrical resistance of human airway epithelia by changing the processing of tight junction proteins. The results are novel and may help explain the beneficial effects of azithromycin in patients with cystic fibrosis, diffuse panbronchiolitis, and community-acquired pneumonia.
Pharmacokinetics of a New, Orally Available Ceftriaxone Formulation in Physical Complexation with a Cationic Analogue of Bile Acid in Rats
Authors: Lee Seulki , Kim Sang Kyoon , Lee Dong Yun , Chae Su Young , Byun Youngro 
Published: April 2006

ABSTRACT
Oral administration of ceftriaxone associated with a bile acid-based new oral carrier, cholylethylenediamine, in 50% propylene glycol to rats at doses of 25 and 50 mg/kg of body weight resulted in a significant increase in intestinal absorption, as evidenced by 55% improvement in the bioavailability, whereas ceftriaxone alone showed a bioavailability of less than 1%.
Erythromycin and Clindamycin Resistance in Group B Streptococcal Clinical Isolates
Authors: Gygax Scott E. , Schuyler Jessica A. , Kimmel Lauren E. , Trama Jason P. , Mordechai Eli , Adelson Martin E. 
Published: April 2006

ABSTRACT

Erythromycin (EM) and clindamycin (CM) susceptibility testing was performed on 222 clinical isolates of group B
Streptococcus
. A multiplex PCR assay was used to detect the
ermB
,
ermTR
, and
mefA/E
antibiotic resistance genes. These results were compared to the phenotypes as determined by the standard EM/CM double disk diffusion assay.
Increasing Prevalence and Diversity of Metallo-β-Lactamases in
Pseudomonas
spp.,
Acinetobacter
spp., and
Enterobacteriaceae
from Korea
Authors: Yong Dongeun , Choi Yeoung Seon , Roh Kyoung Ho , Kim Chang Ki , Park Youn Hee , Yum Jong Hwa , Lee Kyungwon , Chong Yunsop 
Published: April 2006

ABSTRACT

Among imipenem-nonsusceptible isolates, acquired metallo-β-lactamase genes were detected in 36 of 581 (6.2%)
Pseudomonas aeruginosa
isolates, 42 of 44 (95.4%) other
Pseudomonas
species, and 136 of 513 (26.5%)
Acinetobacter
species from 2003 to 2004 at a Korean hospital. Overall,
bla
VIM-2
-like genes were the most prevalent and were also detected in
Enterobacteriaceae
, including
Klebsiella pneumoniae
.
Processing of the Bovine Spongiform Encephalopathy-Specific Prion Protein by Dendritic Cells
Authors: Rybner-Barnier Catherine , Jacquemot Catherine , Cuche Céline , Doré Grégory , Majlessi Laleh , Gabellec Marie-Madeleine , Moris Arnaud , Schwartz Olivier , Di Santo James , Cumano Ana , Leclerc Claude , Lazarini Françoise 
Published: April 2006

ABSTRACTDendritic cells (DC) are suspected to be involved in transmissible spongiform encephalopathies, including bovine spongiform encephalopathy (BSE). We detected the disease-specific, protease-resistant prion protein (PrPbse) in splenic DC purified by magnetic cell sorting 45 days after intraperitoneal inoculation of BSE prions in immunocompetent mice. We showed that bone marrow-derived DC (BMDC) from wild-type or PrP-null mice acquired both PrPbseand prion infectivity within 2 h of in vitro culture with a BSE inoculum. BMDC cleared PrPbsewithin 2 to 3 days of culture, while BMDC infectivity was only 10-fold diminished between days 1 and 6 of culture, suggesting that the infectious unit in BMDC is not removed at the same rate as PrPbseis removed from these cells. Bone marrow-derived plasmacytoid DC and bone marrow-derived macrophages (BMM) also acquired and degraded PrPbsewhen incubated with a BSE inoculum, with kinetics very similar to those of BMDC. PrPbsecapture is probably specific to antigen-presenting cells since no uptake of PrPbsewas observed when splenic B or T lymphocytes were incubated with a BSE inoculum in vitro. Lipopolysaccharide activation of BMDC or BMM prior to BSE infection resulted in an accelerated breakdown of PrPbse. Injected by the intraperitoneal route, BMDC were not infectious for alymphoid recombination-activated gene 20/common cytokine γ chain-deficient mice, suggesting that these cells are not capable of directly propagating BSE infectivity to nerve endings.
Cyclophilin A Renders Human Immunodeficiency Virus Type 1 Sensitive to Old World Monkey but Not Human TRIM5α Antiviral Activity
Authors: Keckesova Zuzana , Ylinen Laura M. J. , Towers Greg J. 
Published: April 2006

ABSTRACT
TRIM5α is an important mediator of antiretroviral innate immunity influencing species-specific retroviral replication. Here we investigate the role of the peptidyl prolyl isomerase enzyme cyclophilin A in TRIM5α antiviral activity. Cyclophilin A is recruited into nascent human immunodeficiency virus type 1 (HIV-1) virions as well as incoming HIV-1 capsids, where it isomerizes an exposed proline residue. Here we show that cyclophilin A renders HIV-1 sensitive to restriction by TRIM5α in cells from Old World monkeys, African green monkey and rhesus macaque. Inhibition of cyclophilin A activity with cyclosporine A, or reducing cyclophilin A expression with small interfering RNA, rescues TRIM5α-restricted HIV-1 infectivity. The effect of cyclosporine A on HIV-1 infectivity is dependent on TRIM5α expression, and expression of simian TRIM5α in permissive feline cells renders them able to restrict HIV-1 in a cyclosporine A-sensitive way. We use an HIV-1 cyclophilin A binding mutant (CA G89V) to show that cyclophilin A has different roles in restriction by Old World monkey TRIM5α and owl monkey TRIM-Cyp. TRIM-Cyp, but not TRIM5α, recruits its tripartite motif to HIV-1 capsid via cyclophilin A and, therefore, HIV-1 G89V is insensitive to TRIM-Cyp but sensitive to TRIM5α. We propose that cyclophilin A isomerization of a proline residue in the TRIM5α sensitivity determinant of the HIV-1 capsid sensitizes it to restriction by Old World monkey TRIM5α. In humans, where HIV-1 has adapted to bypass TRIM5α activity, the effects of cyclosporine A are independent of TRIM5α. We speculate that cyclophilin A alters HIV-1 sensitivity to a TRIM5α-independent innate immune pathway in human cells.
In Vivo Interactions of Ecotropic and Polytropic Murine Leukemia Viruses in Mixed Retrovirus Infections
Authors: Evans Leonard H. , Lavignon Marc , Peterson Karin , Hasenkrug Kim , Robertson Shelly , Malik Frank , Virtaneva Kimmo 
Published: April 2006

ABSTRACT
Mixed retrovirus infections are the rule rather than the exception in mice and other species, including humans. Interactions of retroviruses in mixed infections and their effects on disease induction are poorly understood. Upon infection of mice, ecotropic retroviruses recombine with endogenous proviruses to generate polytropic viruses that utilize different cellular receptors. Interactions among the retroviruses of this mixed infection facilitate disease induction. Using mice infected with defined mixtures of the ecotropic Friend murine leukemia virus (F-MuLV) and different polytropic viruses, we demonstrate several dramatic effects of mixed infections. Remarkably, inoculation of F-MuLV with polytropic MuLVs completely suppressed the generation of new recombinant viruses and dramatically altered disease induction. Coinoculation of F-MuLV with one polytropic virus significantly lengthened survival times, while inoculation with another polytropic MuLV induced a rapid and severe neurological disease. In both instances, the level of the polytropic MuLV was increased 100- to 1,000-fold, whereas the ecotropic MuLV level remained unchanged. Surprisingly, nearly all of the polytropic MuLV genomes were packaged within F-MuLV virions (pseudotyped) very soon after infection. At this time, only a fractional percentage of cells in the mouse were infected by either virus, indicating that the coinoculated viruses had infected the same small subpopulation of susceptible cells. The profound amplification of polytropic MuLVs in coinfected mice may be facilitated by pseudotyping or, alternatively, by transactivation of the polytropic virus in the coinfected cells. This study illustrates the complexity of the interactions between components of mixed retrovirus infections and the dramatic effects of these interactions on disease processes.
Adeno-Associated Virus Type 2 Increases Proteosome-Dependent Degradation of p21WAF1in a Human Papillomavirus Type 31b-Positive Cervical Carcinoma Line
Authors: Alam Samina , Sen Ellora , Brashear Heidi , Meyers Craig 
Published: April 2006

ABSTRACTAdeno-associated virus type 2 (AAV2) seropositivity is negatively correlated with the development of human papillomavirus (HPV)-associated cervical cancer. We have begun analysis of the molecular mechanisms underlying AAV2-mediated oncosuppression through cell cycle regulation in HPV-infected keratinocytes isolated from a low-grade cervical lesion. AAV2 superinfection of HPV type 31b (HPV31b)-positive cells at early times postinfection resulted in degradation of the cyclin-dependent kinase (CDK) inhibitor p21WAF1protein in a proteosome-dependent manner. Downstream consequences of lowering p21WAF1levels included a proportional loss of cyclin E/CDK2 complexes bound to p21WAF1. The loss of stable p21WAF1/cyclin E/CDK2 complexes coincided with an increase in CDK2-associated kinase activity and cyclin E levels. Both events have the potential to enhance the G1/S transition point mediated by active cyclin E/CDK2 complexes. Concurrently, cyclin A and E2F levels were decreased, conditions reminiscent of delayed entrance into the S phase of the cell cycle. On the other hand, infection of primary human foreskin keratinocytes with AAV2 resulted in upregulation of p21WAF1protein levels, reminiscent of a block in G1phase progression. We propose that by downregulating p21WAF1, AAV2 initiates cell cycle activities leading to enhanced G1/S phase-like conditions which may be favorable for AAV2-specific functions and may lead to downstream interference with HPV-associated cervical cancer progression.
The K65R Mutation in Human Immunodeficiency Virus Type 1 Reverse Transcriptase Exhibits Bidirectional Phenotypic Antagonism with Thymidine Analog Mutations
Authors: Parikh Urvi M. , Bacheler Lee , Koontz Dianna , Mellors John W. 
Published: April 2006

ABSTRACTThe K65R mutation in human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) is selected in vitro by manyd-nucleoside analog RT inhibitors (NRTI) but has been rarely detected in treated patients. In recent clinical trials, the K65R mutation has emerged frequently in patients experiencing virologic failure on antiretroviral combinations that do not include 3′-azidothymidine (AZT). The reason for this change is uncertain. To gain insight, we examined trends in the frequency of K65R in a large genotype database, the association of K65R with thymidine analog mutations (TAMs) and other NRTI mutations, and the viral susceptibility profile of HIV-1 with K65R alone and in combination with TAMs. Among >60,000 clinical samples submitted for genotype analysis that contained one or more NRTI resistance mutations, the frequency of K65R increased from 0.4% in 1998 to 3.6% in 2003. Among samples with K65R, a strong negative association was evident with the TAMs M41L, D67N, L210W, T215Y/F, and K219Q/E (P< 0.005) but not with other NRTI mutations, including the Q151M complex. This suggested that K65R and TAMs are antagonistic. To test this possibility, we generated recombinant HIV-1 encoding K65R in two different TAM backgrounds: M41L/L210W/T215Y and D67N/K70R/T215F/K219Q. K65R reduced AZT resistance from >50-fold to <2.5-fold in both backgrounds. In addition, TAMs antagonized the phenotypic effect of K65R, reducing resistance to tenofovir, abacavir, 2′,3′-dideoxycytidine, dideoxyinosine, and stavudine. In conclusion, K65R and TAMs exhibit bidirectional phenotypic antagonism. This antagonism likely explains the negative association of these mutations in genotype databases, the rare emergence of K65R with antiretroviral therapies that contain AZT, and its more frequent emergence with combinations that exclude AZT.