bluuebunny/crossref_metadata_2025_split huggingface dataset:
Non‐genomic immunosuppressive actions of progesterone inhibits PHA‐induced alkalinization and activation in T cells
Authors: Chien Eileen Jea , Chang Ching‐Pang , Lee Wen‐Feng , Su Tsung‐Hsien , Wu Chia‐Hsun 
Published: April 2006

AbstractProgesterone is an endogenous immunomodulator, and can suppress T‐cell activation during pregnancy. When analyzed under a genome time scale, the classic steroid receptor pathway does not have any effect on ion fluxes. Therefore, the aim of this study was to investigate whether the non‐genomic effects on ion fluxes by progesterone could immunosuppress phytohemagglutinin (PHA)‐induced human peripheral T‐cell activation. The new findings indicated that, first, only progesterone stimulated both [Ca2+]i elevation and pHi decrease; in contrast, estradiol or testosterone stimulated [Ca2+]i elevation and hydrocortisone or dexamethasone stimulated pHi decrease. Secondly, the [Ca2+]i increase by progesterone was dependent on Ca2+ influx, and the acidification was blocked by Na+/H+ exchange (NHE) inhibitor, 3‐methylsulphonyl‐4‐piperidinobenzoyl, guanidine hydrochloride (HOE‐694) but not by 5‐(N,N‐dimethyl)‐amiloride (DMA). Thirdly, progesterone blocked phorbol 12‐myristate 13‐acetate (PMA) or PHA‐induced alkalinization, but PHA did not prevent progesterone‐induced acidification. Fourthly, progesterone did not induce T‐cell proliferation; however, co‐stimulation progesterone with PHA was able to suppress PHA‐induced IL‐2 or IL‐4 secretion and proliferation. When progesterone was applied 72 h after PHA stimulation, progesterone could suppress PHA‐induced T‐cell proliferation. Finally, immobilization of progesterone by conjugation to a large carrier molecule (BSA) also stimulated a rapid [Ca2+]i elevation, pHi decrease, and suppressed PHA‐induced proliferation. These results suggested that the non‐genomic effects of progesterone, especially acidification, are exerted via plasma membrane sites and suppress the genomic responses to PHA. Progesterone might act directly through membrane specific nonclassical steroid receptors to cause immunomodulation and suppression of T‐cell activation during pregnancy. J. Cell. Biochem. © 2006 Wiley‐Liss, Inc.
Molecular dynamics simulation and automated docking of the pro‐apoptotic bax protein and its complex with a peptide designed from the Bax‐binding domain of anti‐apoptotic Ku70
Authors: Mancinelli Fabrizio , Caraglia Michele , Budillon Alfredo , Abbruzzese Alberto , Bismuto Ettore 
Published: April 2006

AbstractBax, a multi‐domain protein belonging to the large family of Bcl‐2 proteins, has a pivotal role for the initiation of the cytochrome c‐mediated apoptosis, a vital physiologic process to eliminate damaged or unwanted cells. In response to specific stimuli Bax translocates from cytosol to mitochondria outer membrane where a process of oligomerization occurs with pore formation through which cytochrome c and other death molecules escape. The pro‐death action of Bax is regulated by the interaction with other pro‐survival proteins. However, the conformational changes and the structural details necessary for homo and hetero interaction with other regulating proteins are largely unknown. This article reports a combined investigation of molecular dynamics (MD) simulation and automated docking that evidence the molecular regions of Bax involved in the binding with anti‐apoptotic exapeptide (Bip) designed from Ku70, a subunit of the protein complex essential for non‐homologous DNA repair but that inhibits also the Bax translocation to mitochondria. Since Bip suppresses apoptosis induced by several anti‐cancer drugs, it appears relevant to achieve a better understanding of the structural and dynamical aspects that characterize the Bip–Bax complex in view of potential therapeutic implications. The present results show that the Bax region with the highest affinity for Bip is located in proximity of BH3 homology domain of Bax and also involves the α‐helices 1 and 8. Moreover, the comparison of essential motions of Bax at 300 and 400 K before and after the formation of the complex with Bip evidences how the binding with the exa‐peptide affects the collective motions of specific molecular districts of Bax considered to have functional relevance. J. Cell. Biochem. © 2006 Wiley‐Liss, Inc.
Role of metal‐responsive transcription factor‐1 (MTF‐1) in EGF‐dependent DNA synthesis in primary hepatocytes
Authors: Kimura Tomoki , Itoh Norio , Sone Tomomichi , Kondoh Masuo , Tanaka Keiichi , Isobe Masakazu 
Published: April 2006

AbstractMetal‐responsive transcription factor‐1 (MTF‐1), which is involved in sensing heavy metal load, induces the transcription of several protective genes. The mouse Mtf‐1 gene is essential, and Mtf‐1−/− embryos die from liver degeneration. We showed that DNA synthesis induced in hepatocytes by epidermal growth factor (EGF) was delayed by inhibition of MTF‐1. To inhibit MTF‐1 activity, MTFΔC, a C‐terminal deletion mutant of MTF‐1, was expressed by infection with the virus Ad5MTFΔC. Lactate dehydrogenase (LDH) release and/or caspase‐3/7 activation was not observed under our experimental conditions. The inhibitory effect of MTFΔC on EGF‐dependent DNA synthesis in hepatocytes was not eliminated by zinc addition. EGF‐dependent extracellular signal‐related kinase (ERK) phosphorylation, an essential reaction for EGF‐dependent DNA synthesis, was decreased in MTF‐1‐inhibited hepatocytes. Moreover, decrease of ERK phosphorylation was observed by using siRNA in MTF‐1‐downregulated hepatocytes. These results indicate that MTF‐1 is particularly important for proper hepatocyte proliferation. This is the first report to suggest the function of MTF‐1 in the ERK pathway. J. Cell. Biochem. 99: 485–494, 2006. © 2006 Wiley‐Liss, Inc.
Anti‐apoptotic factor humanin is expressed in the testis and prevents cell‐death in leydig cells during the first wave of spermatogenesis
Authors: Colón Eugenia , Strand Mona‐Lisa , Carlsson‐Skwirut Christine , Wahlgren Aida , Svechnikov Konstantin V. , Cohen Pinchas , Söder Olle 
Published: April 2006

AbstractHumanin (HN) is a 24 amino acids peptide with potent neuro‐survival properties that protects against damage associated with Alzheimer's disease. In the present report, we have demonstrated by immunohistochemical analysis and Western blotting the pattern of expression of rat humanin (HNr) in the testis of 10‐ to 60‐day‐old rats. The Leydig cells of 10‐ and 40‐ day‐old rats expressed this peptide at high levels; and in the testis of 60‐day‐old rats the expression of HNr expanded to include Leydig, endothelial, peritubular and germ cells. As monitored by Western blotting, HNr was released into the medium of cultures of Leydig cells isolated from 10‐, 40‐, and 60‐days‐old rats. HNr stimulated the incorporation of [3H]TdR into DNA of Leydig cells from 10‐days‐old rats, in a manner that indicated promotion of cell survival rather than an increase in the rate of cell multiplication. This peptide also enhanced steroidogenesis by cultured Leydig cells from 10‐ to 40‐day‐old rats both alone and synergistically with IGF‐I. The expression of HNr in cultured Leydig cells increased in response to GH and IGF‐I. In summary, we demonstrated here that HNr was expressed at all stages of maturation in the rat testis. This peptide promoted the survival of Leydig cells in culture and interacted with IGF‐I to stimulate DNA synthesis and steroidogenesis. We propose that HNr is a novel testicular anti‐apoptotic factor. J. Cell. Physiol. 208: 373–385, 2006. © 2006 Wiley‐Liss, Inc.
Ab initio insight on the interaction of ascorbate with Li+, Na+, K+, Be2+, Mg2+, and Ca2+metal cations
Authors: Allen Reeshemah N. , Shukla M. K. , Leszczynski Jerzy 
Published: April 2006

AbstractThe structures and interactions of different possible ascorbic acid anions (ascorbates) with Li+, Na+, K+, Be2+, Mg2+, and Ca2+metal cations were studied at the density functional theory level employing the B3LYP exchange correlation functional and the 6‐311++G(d,p) basis set. The interactions of the metal cations at the different basic sites of ascorbate were considered. The single‐point energy calculations were also performed at the MP2/6‐311++G(d,p) level. Tomasi's polarized continuum model (PCM) was used to evaluate the influence of aqueous solvent on the relative stability of different complexes. The interaction energies for the complexes were corrected for the basis set superposition error (BSSE) using the counterpoise method. The AIM theory was used to characterize the electron density distribution involved in the coordination of studied metal cations with ascorbate. In water, the most preferred position for the interaction of Li+, Na+, and K+cations is through bicoordination with the O2and O3sites of the AAOanion, while all divalent cations Be2+, Mg2+, and Ca2+prefer bicoordination with the O1and O2sites of AAOanion of ascorbic acid. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Fitting potential energy surface of reactive systems via genetic algorithm
Authors: Ferreira Da Cunha Wiliam , Roncaratti Luiz Fernando , Gargano Ricardo , E Silva Geraldo Magela 
Published: April 2006

AbstractWe present a new fitting of the Na+HF potential energy surface (PES) using a new optimization method based on genetic algorithm. Topology studies, such as isoenergetic contours and minimum energy path (MEP), show that the quality of this new PES is comparable to the best PES of literature. These facts suggest that this new approach can be used as a new tool to fit PES of reactive systems. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Use of Stochastic Epidemic Modeling to Quantify Transmission Rates of Colonization With Methicillin-Resistant Staphylococcus Aureus in an Intensive Care Unit
Authors: Forrester Marie , Pettitt Anthony N. 
Published: April 2006

AbstractObjective:To consider statistical methods for estimating transmission rates for colonization of patients with methicillin-resistant Staphylococcus aureus (MRSA) in an intensive care unit (ICU) from three different sources: background contamination, non-isolated patients, and isolated patients.Methods:We developed statistical methods that allowed for the analysis of interval-censored, routine surveillance data and extended the general epidemic model for the flow of patients through the ICU.Results:Within this ICU, the rate of transmission to susceptible patients from a background source of MRSA (0.0092 case per day; 95% confidence interval [CI95], 0.0062–0.0126) is approximately double the rate of transmission from a non-isolated patient (0.0052 case per day; CI95, 0.0013–0.0096) and six times the rate of transmission from an isolated patient (0.0015 case per day; CI95, 0.0001–0.0043). We used the methodology to investigate whether transmission rates vary with workload.Conclusion:Our methodology has general application to infection by and transmission of pathogens in a hospital setting and is appropriate for quantifying the effect of infection control interventions. (Infect Control Hosp Epidemiol 2005;26:598-606)
Modeling Transmission of Methicillin-ResistantStaphylococcus AureusAmong Patients Admitted to a Hospital
Authors: Raboud Janet , Saskin Refik , Simor Andrew , Loeb Mark , Green Karen , Low Don E. , McGeer Allison 
Published: April 2006

AbstractObjective:To determine the impact of the screening test, nursing workload, handwashing rates, and dependence of handwashing on risk level of patient visit on methicillin-resistantStaphylococcus aureus(MRSA) transmission among hospitalized patients.Setting:General medical ward.Methods:Monte Carlo simulation was used to model MRSA transmission (median rate per 1,000 patient-days). Visits by healthcare workers (HCWs) to patients were simulated, and MRSA was assumed to be transmitted among patients via HCWs.Results:The transmission rate was reduced from 0.89 to 0.56 by the combination of increasing the sensitivity of the screening test from 80% to 99% and being able to report results in 1 day instead of 4 days. Reducing the patient-to-nurse ratio from 4.3 in the day and 6.8 at night to 3.8 and 5.7, respectively, reduced the number of nosocomial infections from 0.89 to 0.85; reducing the ratio to 1 and 1, respectively, further reduced the number of nosocomial infections to 0.32. Increases in handwashing rates by 0%, 10%, and 20% for high-risk visits yielded reductions in nosocomial infections similar to those yielded by increases in handwashing rates for all visits (0.89, 0.36, and 0.24, respectively). Screening all patients for MRSA at admission reduced the transmission rate to 0.81 per 1,000 patient-days from 1.37 if no patients were screened.Conclusion:Within the ranges of parameters studied, the most effective strategies for reducing the rate of MRSA transmission were increasing the handwashing rates for visits involving contact with skin or bodily fluid and screening patients for MRSA at admission. (Infect Control Hosp Epidemiol 2005;26:607- 615)
Use of Strain Typing Data to Estimate Bacterial Transmission Rates in Healthcare Settings
Authors: Jackson Brian R. , Thomas Alun , Carroll Karen C. , Adler Frederick R. , Samore Matthew H. 
Published: April 2006

AbstractObjective:To create an affordable and accurate method for continuously monitoring bacterial transmission rates in healthcare settings.Design:We present a discrete simulation model that relies on the relationship between in-hospital transmission rates and strain diversity. We also present a proof of concept application of this model to a prospective molecular epidemiology data set to estimate transmission rates forPseudomonas aeruginosaandStaphylococcus aureus.Setting:Inpatient units of an academic referral center.Patients:All inpatients with nosocomial infections.Intervention:Mathematical model to estimate transmission rates.Results:Maximum likelihood estimates for transmission rates of these two species on different hospital units ranged from 0 to 0.36 transmission event per colonized patient per day.Conclusions:This approach is feasible, although estimates of transmission rates based solely on strain typed clinical cultures may be too imprecise for routine use in infection control. A modest level of surveillance sampling substantially improves the estimation accuracy. (Infect Control Hosp Epidemiol 2005;26:638-645)
Varying Rates of Clostridium Difficile-Associated Diarrhea at Prevention Epicenter Hospitals
Authors: Sohn SeJean , Climo Michael , Diekema Daniel , Fraser Victoria , Herwaldt Loreen , Marino Susan , Noskin Gary , Perl Trish , Song Xiaoyan , Tokars Jerome , Warren David , Wong Edward , Yokoe Deborah S. , Zembower Theresa , Sepkowitz Kent A. ,   Prevention Epicenter Hospitals
Published: April 2006

AbstractBackground:Clostridium difficile-associated diarrhea (CDAD) causes substantial healthcare-associated morbidity. Unlike other common healthcare-associated pathogens, little comparative information is available about CDAD rates in hospitalized patients.Objectives:To determine CDAD rates per 10,000 patient-days and per 1,000 hospital admissions at 7 geographically diverse tertiary-care centers from 2000 to 2003, and to survey participating centers on methods of CDAD surveillance and case definition.Methods:Each center provided specific information for the study period, including case numbers, patient-days, and hospital characteristics. Case definitions and laboratory diagnoses of healthcare-associated CDAD were determined by each institution. Within institutions, case definitions remained consistent during the study period.Results:Overall, mean annual case rates of CDAD were
12.1 per 10,000 patient-days (range, 3.1 to 25.1) and 7.4 per 1,000 hospital admissions (range, 3.1 to 13.1). No significant increases were observed in CDAD case rates during the 4-year interval, either at individual centers or in the Prevention Epicenter hospitals as a whole. Prevention Epicenter hospitals differed in their CDAD case definitions. Different case definitions used by the hospitals applied to a fixed data set resulted in a 30% difference in rates. No associations were identified between diagnostic test or case definition used and the relative rate of CDAD at a specific medical center.Conclusions:Rates of CDAD vary widely at tertiary-care centers across the United States. No significant increases in case rates were identified. The varying clinical and laboratory approaches to diagnosis complicated comparisons between hospitals. To facilitate benchmarking and comparisons between institutions, we recommend development of a more standardized case definition.
Clostridium difficile Among Hospitalized Patients Receiving Antibiotics A Case-Control Study
Authors: Modena Scott , Bearelly Dilip , Swartz Kenneth , Friedenberg Frank K. 
Published: April 2006

AbstractObjectives:Clostridium difficile is the most common cause of infectious nosocomial diarrhea and can be found in up to 30% of asymptomatic hospitalized patients. Our primary aim was to compare the clinical characteristics of hospitalized patients who received antibiotics and developed C. difficile-associated diarrhea (CDAD) with those of hospitalized patients who received antibiotics and did not develop the disease.Design:Case-control study comprising inpatients at a single institution.Patients:Case-patients were defined as patients who had diarrhea and tested positive for C. difficile. Control-patients (matched 4:1 to case-patients) were defined as patients who received antibiotics for at least 5 days and did not develop CDAD.Results:On univariate analysis, nine variables were associated with CDAD. Only three of the variables, need for intensive care, length of stay, and macrolide antibiotic use, were found to be significant (P < .05) on logistic regression analysis. The odds ratios for status as a CDAD case were 3.68 (CI95, 1.44 to 9.40) for stay in the intensive care unit and 1.03 (CI95, 1.02 to 1.05) for each day of hospital stay. Receipt of macrolide antibiotics reduced risk significantly; the odds ratio was 0.23 (CI95, 0.19 to 0.87).Conclusions:We identified need for intensive care and length of stay as important risk factors for the development of CDAD. We also identified macrolide antibiotic use as protective against its development. Patients receiving intensive care may represent a population to study for targeted prophylaxis.
Octenidine Hydrochloride for the Care of Central Venous Catheter Insertion Sites in Severely Immunocompromised Patients
Authors: Tietz Andreas , Frei Reno , Dangel Marc , Bolliger Dora , Passweg Jakob R. , Gratwohl Alois , Widmer Andreas F. 
Published: April 2006

AbstractObjective:To determine the efficacy and tolerability of octenidine hydrochloride, a non-alcoholic skin antiseptic, for the care of central venous catheter (CVC) insertion sites.Design:Prospective, observational study.Setting:Bone marrow transplantation unit of a university hospital.Patients:All consecutive patients with a nontunneled CVC were enrolled prospectively after informed consent.Methods:Octenidine hydrochloride (0.1%) was applied for disinfection at the CVC insertion site during dressing changes. The following cultures were performed weekly as well as at the occurrence of any systemic inflammatory response syndrome criteria: cultures of the skin surrounding the CVC entry site, cultures of the three-way hub connected to the CVC, blood cultures, and cultures of the CVC tip on removal. Enhanced microbiological methods (skin swabs of a 24-cm2 standardized area, roll plate, and sonication of catheter tips) were applied.Results:One hundred thirty-five CVCs were inserted in 62 patients during the study period and remained for a mean period of 19.1 days, corresponding to 2,462 catheter-days. Bacterial density at the insertion site declined substantially over time, and most cultures became negative 2 weeks after insertion. Only 6 patients had a documented catheter-related bloodstream infection. The incidence density was 2.39 catheter infections per 1,000 catheter-days. No side effects were noted with application of the antiseptic.Conclusions:Disinfection with a skin antiseptic that contains octenidine hydrochloride is highly active and well tolerated. It leads to a decrease in skin colonization over time and may be a new option for CVC care.
A Large Outbreak of Hepatitis B Virus Infections Associated With Frequent Injections at a Physician's Office
Authors: Samandari Taraz , Malakmadze Naile , Balter Sharon , Perz Joseph F. , Khristova Marina , Swetnam Leah , Bornschlegel Katherine , Phillips Michael S. , Poshni Iqbal A. , Nautiyal Preeti , Nainan Omana V. , Bell Beth P. , Williams Ian T. 
Published: April 2006

AbstractObjectives:To determine whether hepatitis B virus (HBV) transmission occurred among patients visiting a physician's office and to evaluate potential transmission mechanisms.Design:Serologic survey, retrospective cohort study, and observation of infection control practices.Setting:Private medical office.Patients:Those visiting the office between March 1 and December 26, 2001.Results:We identified 38 patients with acute HBV infection occurring between February 2000 and February 2002. The cohort study, limited to the 10 months before outbreak detection, included 91 patients with serologic test results and available charts representing 18 case-patients and 73 susceptible patients. Overall, 67 patients (74%) received at least one injection during the observation period. Case-patients received a median of 14 injections (range, 2-25) versus 2 injections (range, 0-17) for susceptible patients (P < .001). Acute infections occurred among 18 (27%) of 67 who received at least one injection versus none of 24 who received no injections (RR, 13.6; CI95, 2.4-undefined). Risk of infection increased 5.2-fold (CI95, 0.6-47.3) for those with 3 to 6 injections and 20.0-fold (CI95, 2.8-143.5) for those with more than 6 injections. Typically, injections consisted of doses of atropine, dexamethasone, vitamin B12, or a combination of these mixed in one syringe. HBV DNA genetic sequences of 24 patients with acute infection and 4 patients with chronic infection were identical in the 1,500-bp region examined. Medical staff were seronegative for HBV infection markers. The same surface was used for storing multidose vials, preparing injections, and dismantling used injection equipment.Conclusion:Administration of unnecessary injections combined with failure to separate clean from contaminated areas and follow safe injection practices likely resulted in patient-to-patient HBV transmission in a private physician's office.