bluuebunny/crossref_metadata_2025 huggingface dataset:
ORIGINAL ARTICLE: Maternal Plasma Concentration of the Pro‐Inflammatory Adipokine Pre‐B‐Cell‐Enhancing Factor (PBEF)/Visfatin Is Elevated In Pregnant Patients with Acute Pyelonephritis
Authors: Mazaki‐Tovi Shali , Vaisbuch Edi , Romero Roberto , Kusanovic Juan Pedro , Chaiworapongsa Tinnakorn , Kim Sun Kwon , Nhan‐Chang Chia‐Ling , Gomez Ricardo , Yoon Bo H. , Yeo Lami , Mittal Pooja , Ogge Giovanna , Gonzalez Juan M. , Hassan Sonia S.
Published: January 2010

Citation Mazaki‐Tovi S, Vaisbuch E, Romero R, Kusanovic JP, Chaiworapongsa T, Kim SK, Nhan‐Chang C‐L, Gomez R, Yoon BH, Yeo L, Mittal P, Ogge G, Gonzalez JM, Hassan SS. Maternal plasma concentration of the pro‐inflammatory adipokine pre‐B‐cell‐enhancing factor (PBEF)/visfatin is elevated in pregnant patients with acute pyelonephritis. Am J Reprod Immunol 2010; 63: 252–262

Problem  Visfatin/pre‐B‐cell‐enhancing factor (PBEF) has been implicated in the regulation of the innate immune system, as well as in glucose metabolism. Specifically, visfatin plays a requisite role in delayed neutrophil apoptosis in patients with sepsis. The aim of this study was to determine whether pyelonephritis during pregnancy is associated with changes in maternal plasma visfatin concentration in normal weight and overweight/obese patients.

Method of study  This cross‐sectional study included the following groups: (1) normal pregnant women (n = 200) and (2) pregnant women with pyelonephritis (n = 40). Maternal plasma visfatin concentrations were determined by ELISA. Non‐parametric statistics was used for analyses.

Results  (1) The median maternal plasma visfatin concentration was significantly higher in patients with pyelonephritis than in those with a normal pregnancy; (2) among overweight/obese pregnant women, those with pyelonephritis had a significantly higher median plasma visfatin concentration than women with a normal pregnancy; and (3) pyelonephritis was independently associated with higher maternal plasma visfatin concentrations after adjustment for maternal age, pre‐gestational body mass index, smoking status, gestational age at sampling, and birthweight.

Conclusion  Acute pyelonephritis during pregnancy is associated with a high circulating maternal visfatin concentration. These findings suggest that visfatin/PBEF may play a role in the regulation of the complex and dynamic crosstalk between inflammation and metabolism during pregnancy.
Does Premarital Cohabitation Predict Subsequent Marital Stability and Marital Quality? A Meta‐Analysis
Authors: Jose Anita , Daniel O’Leary K. , Moyer Anne
Published: January 2010

Cohabitation with a romantic partner has become common in recent decades. This meta‐analysis examined the link between premarital cohabitation and marital stability ( k = 16) and marital quality ( k = 12). Cohabitation had a significant negative association with both marital stability and marital quality. The negative predictive effect on marital stability, however, did not remain when only cohabitation with the eventual marital partner was analyzed, suggesting that these cohabitors may attach more long‐term meaning to living together. Moderator analyses demonstrated that effects of cohabitation have remained consistent over time, despite the fact that cohabitation has become more normative.
Life Course Stage in Young Adulthood and Intergenerational Congruence in Family Attitudes
Authors: Bucx Freek , Raaijmakers Quinten , Van Wel Frits
Published: January 2010

We investigated how intergenerational congruence in family‐related attitudes depends on life course stage in young adulthood. Recent data from the Netherlands Kinship Panel Study were used; the present sample included 2,041 dyads of young adults and their parents. Findings are discussed in terms of the elasticity in intergenerational attitude congruence in response to young adults' life course transitions. Our results suggest that intergenerational congruence in attitudes about partnership (e.g., marriage, cohabitation, divorce, women's and men's family roles) decreases after young adults have left the parental home and increases when young adults enter parenthood. Congruence concerning intergenerational obligations was not related to young adults' life course stage.
“Women's Work”? Women Partners of Transgender Men Doing Housework and Emotion Work
Authors: Pfeffer Carla A.
Published: January 2010

Despite increasing family studies research on same‐sex cohabiters and families, the literature is virtually devoid of transgender and transsexual families. To bridge this gap, I present qualitative research narratives on household labor and emotion work from 50 women partners of transgender and transsexual men. Contrary to much literature on “same‐sex” couples, the division of household labor and emotion work within these contemporary families cannot simply be described as egalitarian. Further, although the forms of emotion work and “gender strategies,”“family myths,” and “accounts” with which women partners of trans men engage resonate with those from women in (non‐trans) heterosexual and lesbian couples, they are also distinct, highlighting tensions among personal agency, politics, and structural inequalities in family life.
Separate Spheres or Increasing Equality? Changing Gender Beliefs in Postwar Japan
Authors: Lee Kristen Schultz , Tufiş Paula A. , Alwin Duane F.
Published: January 2010

This research investigates change in gender beliefs in Japan during a period of economic hard times in the late 1990s. Using data from the International Social Survey Programme on the Japanese population from 1994 (n = 1,054) and 2002 (n = 872), we examined how cohort replacement and intracohort change contributed to changes in gender beliefs. We found important differences from the patterns of change reported for many Western countries, namely, a decoupling between societal trends in the female labor force participation rate and beliefs about gender. Such differences may be attributable to factors such as the high societal valuation of the housewife role compared to that in other postindustrial countries and sanctions against full‐time employment for women in Japan.
Theoretical study of lipid biosynthesis in wild‐type Escherichia coli and in a protoplast‐type L‐form using elementary flux mode analysis
Authors: Kenanov Dimitar , Kaleta Christoph , Petzold Andreas , Hoischen Christian , Diekmann Stephan , Siddiqui Roman A. , Schuster Stefan
Published: January 2010

In the present study, we investigated lipid biosynthesis in the bacterium Escherichia coli by mathematical modeling. In particular, we studied the interaction between the subsystems producing unsaturated and saturated fatty acids, phospholipids, lipid A, and cardiolipin. The present analysis was carried out both for the wild‐type and for several in silico knockout mutants, using the concept of elementary flux modes. Our results confirm that, in the wild type, there are four main products: L1‐phosphatidylethanolamine, lipid A, lipid A (cold‐adapted), and cardiolipin. We found that each of these compounds is produced on several different routes, indicating a high redundancy of the system under study. By analysis of the elementary flux modes remaining after the knockout of genes of lipid biosynthesis, and comparison with publicly available data on single‐gene knockouts in vivo, we were able to determine the metabolites essential for the survival of the cell. Furthermore, we analyzed a set of mutations that occur in a cell wall‐free mutant of Escherichia coli W1655F+. We postulate that the mutant is not capable of producing both forms of lipid A, when the combination of mutations is considered to make a nonfunctional pathway. This is in contrast to gene essentiality data showing that lipid A synthesis is indispensable for the survival of the cell. The loss of the outer membrane in the cell wall‐free mutant, however, shows that lipid A is dispensable as the main component of the outer surface structure in this particular E. coli strain.
Bioavailability of backbone cyclic PK/PBAN neuropeptide antagonists – inhibition of sex pheromone biosynthesis elicited by the natural mechanism in Heliothis peltigera females
Authors: Hariton Aliza , Ben‐Aziz Orna , Davidovitch Michael , Altstein Miriam
Published: January 2010

The bioavailability (i.e. ability to penetrate the insect cuticle, to reach the target organ and to exert bioactivity) of two backbone cyclic (BBC) pyrokinin/pheromone biosynthesis‐activating neuropeptide (PK/PBAN) antagonistic peptides was tested by applying them topically to Heliothis peltigera females and monitoring the resulting inhibition of sex pheromone production elicited by the natural (endogenous) mechanism during scotophase. Peptides were applied at various time points before the onset of scotophase, in aqueous or organic solvents, and pheromone content was examined at the 5th or 6th hour of scotophase. Both peptides penetrated the cuticle very efficiently and inhibited sex pheromone biosynthesis elicited by the natural mechanism for up to 8 or 9 h after application. The degree of inhibition differed between solvents: those applied in double‐distilled water (DDW) were more active than those applied in dimethylsulfoxide (inhibition by 53–73% and 15–38%, respectively, for BBC‐25, and 46–67% and 36–40%, respectively for BBC‐28). Peptides applied in dimethylsulfoxide and hexane exhibited slightly more persistent inhibitory activity than those applied in DDW. The solvents themselves did not affect sex pheromone production. Multiple applications (at −2, 0, +2 and +4 h) resulted in almost complete (87%) inhibition of sex pheromone biosynthesis, compared with 52% inhibition following a single application. The present study is the first demonstration of the ability of topically applied PK/PBAN antagonists to inhibit sex pheromone biosynthesis elicited by the natural mechanism in female moths, and provides important information on the bioavailability of BBC peptides and the mechanism responsible for sex pheromone production in these insects.
Catalytic reaction mechanism of Pseudomonas stutzeri l‐rhamnose isomerase deduced from X‐ray structures
Authors: Yoshida Hiromi , Yamaji Masatsugu , Ishii Tomohiko , Izumori Ken , Kamitori Shigehiro
Published: January 2010

l‐Rhamnose isomerase (l‐RhI) catalyzes the reversible isomerization of l‐rhamnose to l‐rhamnulose. Pseudomonas stutzeril‐RhI, with a broad substrate specificity, can catalyze not only the isomerization of l‐rhamnose, but also that between d‐allose and d‐psicose. For the aldose–ketose isomerization by l‐RhI, a metal‐mediated hydride‐shift mechanism has been proposed, but the catalytic mechanism is still not entirely understood. To elucidate the entire reaction mechanism, the X‐ray structures of P. stutzeril‐RhI in an Mn2+‐bound form, and of two inactive mutant forms of P. stutzeril‐RhI (S329K and D327N) in a complex with substrate/product, were determined. The structure of the Mn2+‐bound enzyme indicated that the catalytic site interconverts between two forms with the displacement of the metal ion to recognize both pyranose and furanose ring substrates. Solving the structures of S329K–substrates allowed us to examine the metal‐mediated hydride‐shift mechanism of l‐RhI in detail. The structural analysis of D327N–substrates and additional modeling revealed Asp327 to be responsible for the ring opening of furanose, and a water molecule coordinating with the metal ion to be involved in the ring opening of pyranose.

Structured digital abstract

MINT‐7384817: l‐RhI (uniprotkb:Q75WH8) and l‐RhI (uniprotkb:Q75WH8) bind (MI:0407) by X‐ray crystallography (MI:0114)
Effects of Eicosapentaenoic Acid Supplementation on Immunoglobulin A Nephropathy
Authors: Uchiyama‐Tanaka Yoko , Mori Yasukiyo
Published: January 2010

Eicosapentaenoic acid (EPA), which is purified from fish oil, attenuates inflammatory responses by decreasing eicosanoid and cytokine production. EPA reportedly improves renal survival in patients with immunoglobulin (Ig)A nephropathy; however, this is unconfirmed. We studied the effects of EPA on IgA nephropathy patients. Eighteen biopsy‐confirmed IgA nephropathy patients (aged 31 ± 3 years) were enrolled. The prognoses based on glomerular findings were good (N = 5), relatively poor (N = 12), and poor (N = 1). EPA was administered at 1.8 g/day for 12 months. Five biopsy‐confirmed IgA nephropathy patients were enrolled as control subjects. Administration of other drugs used to treat IgA nephropathy was not changed. The estimated creatinine clearance (eCCr), serum creatinine (Cr) concentration, urinary protein creatinine ratio (U/P), and other clinical parameters were checked. In the EPA group, the Cr went from 0.8 ± 0.2 mg/dL to 0.7 ± 0.2 mg/dL after 12 months of EPA treatment, and the U/P went from 550 ± 580 mg/g Cr to 330 ± 920 mg/g Cr. The values did not differ significantly; however, Cr and U/P tended to improve, with no adverse effects from the EPA. The eCCr improved significantly (99 ± 7–110 ± 8 mL/min, P = 0.001) in the EPA group, but not in the control group (126 ± 12–120 ± 13, P > 0.05). The effect of EPA in patients with IgA nephropathy is not pronounced, but these results suggest that EPA is a safe and worthwhile supplement to the drugs used to treat this disease.
Beneficial Therapeutic Effect of Plasmapheresis After Unsuccessful Treatment With Corticosteroids in Two Patients With Severe Toxic Epidermal Necrolysis
Authors: Szczeklik Wojciech , Nowak Ilona , Seczynska Bozena , Sega Aurelia , Krolikowski Wieslaw , Musial Jacek
Published: January 2010

Toxic epidermal necrolysis (TEN) is a rare, life‐threatening disease with a high mortality rate. It is linked to drug toxicity and characterized by epidermal necrolysis with mucositis and conjunctivitis. Treatment is not established due to the unknown pathogenesis and lack of randomized clinical trials. It is mostly based on withdrawal of the culprit drug and symptom‐related approach. The role of corticosteroids and plasmapheresis in the disease treatment remains controversial. We present two patients with severe TEN (both with >80% body skin surface involvement) treated unsuccessfully with corticosteroids followed by plasmapheresis. Plasmapheresis led to prompt improvement, with extensive reepithealization of the skin, and eventually total recovery of both patients. In severe TEN unresponsive to corticosteroids, treatment with plasmapheresis should be considered.
Femoral diaphysis fractures in cattle: 26 cases (1994–2005)
Authors: Nichols S , Anderson DE , Miesner MD , Newman KD
Published: January 2010

Objective This retrospective study was conducted to evaluate the outcome for cattle with diaphyseal fractures of the femur, but not including capital physeal injuries.

Methods Sources of information were medical records of cattle having a definitive diagnosis of diaphyseal femoral fractures and telephone survey of owners.

Results Medical records for 26 cattle with femoral fracture were found; of the 20 aged less than 2 months, 15 were treated surgically, 4 conservatively (stall rest) and 1 was euthanased without treatment. The surgical treatment varied according to the configuration of the fracture and the surgeon's experience. Surgery for mid‐diaphyseal fractures had a significantly better surgical outcome then distal diaphyseal fractures (P < 0.05), as there were significantly fewer postoperative complications. Of the 15 calves treated surgically, 10 were discharged from hospital and 5 were retained in the herd without noticeable lameness. Of the 4 calves treated conservatively, 3 were alive at follow‐up, but 2 were still lame. Of the 6 older cattle, 3 were euthanased without treatment and 3 were treated conservatively, 2 of which were alive at follow‐up but 1 was still lame.

Conclusion Conservative treatment of femur fracture in cattle is possible but associated with complications during the convalescence. Continued research is needed to optimise distal diaphyseal fracture stabilisation in young cattle.
Seminoma in a southern black rhinoceros (Diceros bicornis minor): diagnosis, surgical management and effect on fertility
Authors: Portas TJ , Hildebrandt TB , Bryant BR , Göritz F , Hermes R
Published: January 2010

A testicular mass was identified by ultrasonography performed during a routine reproductive evaluation of an adult male southern black rhinoceros (Diceros bicornis minor). Histological examination of a testicular biopsy supported a presumptive diagnosis of testicular neoplasia. Hemi‐castration was performed to excise the affected testis and a pathological diagnosis of a seminoma was made. Assessment of semen suggested reduced fertility as a consequence of the neoplastic process, but hemi‐castration prevented further growth and metastasis of the tumour and ensured the animal's breeding potential. This is the second documented case of a seminoma in a rhinoceros species and the first case in a black rhinoceros.
Factors affecting the relationship between arterial and end‐tidal carbon dioxide pressures in the anaesthetised horse
Authors: Rainger JE , Dart CM , Perkins NR
Published: January 2010

Objective To assess the effects of the duration of anaesthesia, position of recumbency, mode of ventilation, anaesthetic drug protocol, patient age and type of surgical procedure on the usefulness of capnometry as a measure of the partial pressure of arterial carbon dioxide (Paco2) during general anaesthesia in horses.

Design A prospective study compared the Paco2values with those of partial pressure of end‐tidal carbon dioxide (ETco2) in horses anaesthetised for elective or emergency surgical procedures. The difference between Paco2and ETco2(Paco2− ETco2) and the physiological dead space to tidal volume ratio (VD/VT) were calculated. The effects of the study parameters on these variables was determined.

Results The agreement between Paco2and ETco2was poor. Paco2− ETco2and VD/VTduring the first 60 min of anaesthesia was significantly less than after 60 min of anaesthesia. Mode of ventilation, position of recumbency, anaesthetic drug protocol, patient age and type of procedure did not have a significant affect on either value.

Conclusions Paco2− ETco2in anaesthetised horses can be large, making ETco2unreliable as a predictor of Paco2and for assessment of pulmonary ventilation. For anaesthesia lasting less than 60 min at least one blood gas analysis of an arterial blood sample is required to assess Paco2− ETco2. Arterial blood gas analysis should be repeated after 60 min of general anaesthesia.
Retrospective study of 108 foals with septic osteomyelitis
Authors: Neil KM , Axon JE , Begg AP , Todhunter PG , Adams PL , Fine AE , Caron JP , Adkins AR
Published: January 2010

Objective To determine the clinical characteristics, short‐term outcome and future athletic performance of foals with septic osteomyelitis.

Design Retrospective clinical study of 108 Thoroughbred foals with radiographic evidence of bone infection that were presented at the Scone Veterinary Hospital between August 1995 and December 2001. Medical records were reviewed and information concerning signalment, the clinical, laboratory and radiographic findings, treatment and outcome was obtained. Racing records were obtained and evaluated for surviving foals that had reached racing age.

Results Mean age of foals at initial evaluation was 39 days (range 1–180 days); 21 foals had multiple radiographic bone lesions (19.4%), and 76 had concurrent septic arthritis (70.4%). The most frequently affected bones were the femur, tibia and distal phalanx. In total, 87 foals were discharged from the hospital (80.6%), 79 survived long‐term to reach racing age and 52 raced (65.8%). Overall, 48% (52/108) of the foals treated for osteomyelitis raced. Foals less than 30 days of age at the time of diagnosis, critically ill foals and those with multiple bones or joints affected were significantly less likely to be discharged from hospital. Multiple septic joints, but not multiple bone involvement, had an unfavourable prognosis for racing.

Conclusions The prognosis for survival of foals with septic osteomyelitis or osteitis is favourable. Multiple bone or joint involvement is an important short‐term prognostic indicator; however, the involvement of multiple joints, but not multiple infected bones, is associated with an unfavourable prognosis for racing.
Sequential auctions: theory and evidence from the Seattle Fur Exchange
Authors: Lambson Val E. , Thurston Norman K
Published: January 2010

We develop a model that incorporates salient features of the Seattle Fur Exchange: identical lots of furs are auctioned sequentially, bids must be raised by specified increments, and the winner of a lot has the privilege of beginning the bidding on the subsequent lot. Predictions of the theory are consistent with the data. Revenue implications of the theory are also explored.
Cooperative investments induced by contract law
Authors: Schweizer Urs
Published: January 2010

I revisit the economic analysis of contract law for a setting of cooperative investments. While Che and Chung (1999) have shown that expectation damages perform rather poorly, I argue that this negative result follows from their implicit assumption of unilateral expectation damages. Yet the very nature of cooperative investments gives rise to the possibility that both parties may claim expectation damages. I show that such a regime of bilateral expectation damages provides the incentives for the first‐best solution even in a framework of binary choice where, for selfish investments, the traditional overreliance result would hold.
Reputational cheap talk
Authors: Ottaviani Marco , Sørensen Peter Norman
Published: January 2010

We analyze information reporting by a privately informed expert concerned about being perceived to have accurate information. When the expert's reputation is updated on the basis of the report as well as the realized state, the expert typically does not wish to truthfully reveal the signal observed. The incentives to deviate from truth telling are characterized and shown to depend on the information structure. In equilibrium, experts can credibly communicate only part of their information. Our results also hold when experts have private information about their own accuracy and care about their reputation relative to others.
Price‐matching guarantees
Authors: Moorthy Sridhar , Winter Ralph A.
Published: January 2010

Are price‐matching guarantees anticompetitive? We examine the incentives for price‐matching guarantees in markets where information about prices is costly. The conventional explanation of price matching as facilitating cartel pricing finds some theoretical support, but our model provides an additional explanation. A price‐matching guarantee may be a credible and easily understood means of communicating to uninformed consumers that a firm is low priced. The credibility of the signal is assured by the behavior of informed consumers. We contrast the testable implications of our model with those arising from two theories of price matching as anticompetitive, and show that available evidence supports the signalling theory.
Laparoscopic management of recurrent rupture of an adnexal mass in the second trimester of pregnancy: A case report
Authors: Hayasaka S , Murakami T , Nabeshima H , Terada Y , Yaegashi N
Published: January 2010

We present the case of a patient who developed an acute abdomen after recurrent rupture of an ovarian cyst in the first trimester of pregnancy. After the third rupture and recurrence of the cyst, we performed laparoscopic ovarian cystectomy at 13 weeks of gestation. She went on to deliver a healthy neonate via elective cesarean section at 38 weeks of gestation. To our knowledge, this is the first report of a recurrent rupturing ovarian cyst during pregnancy. Our patient's case suggests that idiopathic recurrent rupture of an ovarian cyst can occur during early pregnancy. Careful follow‐up and timely surgical intervention for recurrent rupture of an ovarian cyst are needed in order to reduce the risk of pregnancy loss.
New horizons in simulation training for endoscopic surgery
Authors: King D. , Lee H. , Lewis T. , Di Marco A. , Kneebone R. , Darzi A.
Published: January 2010

In recent years there has been both a paradigm shift in the way surgery is carried out and also in the way in which we train health professionals undertaking interventional procedures. Endoscopic procedures have replaced many traditional operations and the benefits of such an approach to patient care are well documented. However, evidence exists of higher patient complications during a surgeon's learning curve in endoscopic surgery, and it is now considered essential that endoscopic skills are learned in training laboratories rather than on patients. A new model of structured education, where surgical skills are practiced on models and virtual reality simulators, is set to replace the traditional apprenticeship model of training. Simulation is a rapidly evolving field that can provide a safe and increasingly realistic learning environment for trainees to practice in. This paper explores the current role of simulation in endoscopic training and provides a review of the developments in the field, including advances in simulation technology, progress in curriculum design and the use of simulation in nontechnical skills training.
Experiences from nonevaporable getter-coated vacuum chambers at the MAX II synchrotron light source
Authors: Hansson A. , Wallén E. , Berglund M. , Kersevan R. , Hahn M.
Published: January 2010

Vacuum chambers coated with nonevaporable getter (NEG) materials have been used in straight sections of synchrotron light sources for the past 10years. The MAX II storage ring, where four NEG-coated insertion device vacuum chambers and three NEG-coated dipole vacuum chambers have been installed, is the first synchrotron light source to also use NEG-coated dipole vacuum chambers. In connection with the installation of the latest two NEG-coated dipole chambers in April 2009, the evolution of the pressure and lifetime-limiting effects in MAX II has been determined from measurements with movable scrapers. The results have been compared with results from scraper measurements done in 2003, before any NEG-coated vacuum chambers were installed in the storage ring. Less than three months after the installation of the latest dipole chambers the vacuum system in MAX II was performing well with a pressure already lower than the pressure measured in 2003.
Stenciled conducting bismuth nanowires
Authors: Savu Veronica , Neuser Sam , Villanueva Guillermo , Vazquez-Mena Oscar , Sidler Katrin , Brugger Juergen
Published: January 2010

Stencil lithography is used here for the fabrication of bismuth nanowires using thermal evaporation. This technique provides good electrical contact resistance by having the nanowire structure and the contact pads deposited at the same time. It has also the advantage of modulating nanowires’ height as a function of their width. As the evaporated material deposits on the stencil mask, the apertures shrink in size until they are fully clogged and no more material can pass through. Thus, the authors obtain variable-height (from 27 to 95 nm) nanowires in the same evaporation. Upon their morphological (scanning electron microscopy and atomic force microscopy) and electrical characterizations, the authors obtain their resistivity, which is independent of the nanowire size and is the lowest reported for physical vapor deposition of Bi nanowires (1.2×10−3 Ω cm), only an order of magnitude higher than that of bulk bismuth.
Identification of a Class of HCV Inhibitors Directed Against the Nonstructural Protein NS4B
Authors: Cho Nam-Joon , Dvory-Sobol Hadas , Lee Choongho , Cho Sang-Joon , Bryson Paul , Masek Marilyn , Elazar Menashe , Frank Curtis W. , Glenn Jeffrey S.
Published: January 2010

An activity identified in hepatitis C virus NS4B paves the way for a distinct new class of antivirals.
Optimizing the Delivery of Cancer Drugs That Block Angiogenesis
Authors: Cao Yihai , Langer Robert
Published: January 2010

Optimal delivery systems for antiangiogenic drugs must be developed to maximize clinical benefits and minimize adverse effects in cancer patients.
Penicillin Sulfone Inhibitors of Class D β-Lactamases
Authors: Drawz Sarah M. , Bethel Christopher R. , Doppalapudi Venkata R. , Sheri Anjaneyulu , Pagadala Sundar Ram Reddy , Hujer Andrea M. , Skalweit Marion J. , Anderson Vernon E. , Chen Shu G. , Buynak John D. , Bonomo Robert A.
Published: January 2010

OXA β-lactamases are largely responsible for β-lactam resistance inAcinetobacterspp. andPseudomonas aeruginosa, two of the most difficult-to-treat nosocomial pathogens. In general, the β-lactamase inhibitors used in clinical practice (clavulanic acid, sulbactam, and tazobactam) demonstrate poor activity against class D β-lactamases. To overcome this challenge, we explored the abilities of β-lactamase inhibitors of the C-2- and C-3-substituted penicillin and cephalosporin sulfone families against OXA-1, extended-spectrum (OXA-10, OXA-14, and OXA-17), and carbapenemase-type (OXA-24/40) class D β-lactamases. Three C-2-substituted penicillin sulfone compounds (JDB/LN-1-255, JDB/LN-III-26, and JDB/ASR-II-292) showed lowKivalues for the OXA-1 β-lactamase (0.70 ± 0.14 → 1.60 ± 0.30 μM) and demonstrated significantKiimprovements compared to the C-3-substituted cephalosporin sulfone (JDB/DVR-II-214), tazobactam, and clavulanic acid. The C-2-substituted penicillin sulfones JDB/ASR-II-292 and JDB/LN-1-255 also demonstrated lowKis for the OXA-10, -14, -17, and -24/40 β-lactamases (0.20 ± 0.04 → 17 ± 4 μM). Furthermore, JDB/LN-1-255 displayed stoichiometric inactivation of OXA-1 (the turnover number, i.e., the partitioning of the initial enzyme inhibitor complex between hydrolysis and enzyme inactivation [tn] = 0) andtns ranging from 5 to 8 for the other OXA enzymes. Using mass spectroscopy to study the intermediates in the inactivation pathway, we determined that JDB/LN-1-255 inhibited OXA β-lactamases by forming covalent adducts that do not fragment. On the basis of the substrate and inhibitor kinetics of OXA-1, we constructed a model showing that the C-3 carboxylate of JDB/LN-1-255 interacts with Ser115 and Thr213, the R-2 group at C-2 fits between the space created by the long B9 and B10 β strands, and stabilizing hydrophobic interactions are formed between the pyridyl ring of JDB/LN-1-255 and Val116 and Leu161. By exploiting conserved structural and mechanistic features, JDB/LN-1-255 is a promising lead compound in the quest for effective inhibitors of OXA-type β-lactamases.
Antibodies Fused to Innate Immune Molecules Reduce Initiation ofCryptosporidium parvumInfection in Mice
Authors: Imboden Michael , Riggs Michael W. , Schaefer Deborah A. , Homan E. Jane , Bremel Robert D.
Published: January 2010

At present no completely effective treatments are available forCryptosporidium parvuminfections in humans and livestock. Based on previous data showing the neutralizing potential of a panel of monoclonal antibodies developed againstC. parvum, and based on the fact that innate immune peptides and enzymes have anticryptosporidial activity, we engineered several of these antibodies into antibody-biocide fusion proteins. We hypothesized that the combination of high-affinity antibody targeting with innate immune molecule-mediated killing would result in a highly effective new antiprotozoal agent. To test this hypothesis, we expressed antibody-biocide fusion proteins in a mammalian cell culture system and used the resulting products forin vitroandin vivoefficacy experiments. Antibody-biocide fusion proteins efficiently bound to, and destroyed,C. parvumsporozoitesin vitrothrough a membrane-disruptive mechanism. When antibody-biocide fusion proteins were administered orally to neonatal mice in a prophylactic model of cryptosporidiosis, the induction of infection was reduced by as much as 81% in the mucosal epithelium of the gut, as determined on the basis of histopathological scoring of infectious stages. Several versions of antibody fusion proteins that differed in antigen specificity and in the biocide used had strong inhibitory effects on the initiation of infection. The results lay the groundwork for the development of a new class of antimicrobials effective againstCryptosporidium.
Rapamycin Protects Mice from Staphylococcal Enterotoxin B-Induced Toxic Shock and Blocks Cytokine ReleaseInVitroandIn Vivo
Authors: Krakauer Teresa , Buckley Marilyn , Issaq Haleem J. , Fox Stephen D.
Published: January 2010

Staphylococcal enterotoxins are potent activators for human T cells and cause lethal toxic shock. Rapamycin, an immunosuppressant, was tested for its ability to inhibit staphylococcal enterotoxin B (SEB)-induced activation of human peripheral blood mononuclear cells (PBMC)in vitroand toxin-mediated shock in mice. Stimulation of PMBC by SEB was effectively blocked by rapamycin as evidenced by the inhibition of tumor necrosis factor alpha (TNF-α), interleukin 1β (IL-1β), IL-6, IL-2, gamma interferon (IFN-γ), monocyte chemoattractant protein 1 (MCP-1), macrophage inflammatory protein 1α (MIP-1α), MIP-1β, and T-cell proliferation.In vivo, rapamycin protected 100% of mice from lethal shock, even when administered 24 h after intranasal SEB challenge. The serum levels of MCP-1 and IL-6, after intranasal exposure to SEB, were significantly reduced in mice given rapamycin versus controls. Additionally, rapamycin diminished the weight loss and temperature fluctuations elicited by SEB.
Molecular Cloning and Heterologous Expression of a Biosynthetic Gene Cluster for the Antitubercular Agent
d
-Cycloserine Produced by
Streptomyces lavendulae
Authors: Kumagai Takanori , Koyama Yusuke , Oda Kosuke , Noda Masafumi , Matoba Yasuyuki , Sugiyama Masanori
Published: January 2010

In the present study, we successfully cloned a 21-kb DNA fragment containing a
d
-cycloserine (DCS) biosynthetic gene cluster from a DCS-producing
Streptomyces
lavendulae
strain, ATCC 11924. The putative gene cluster consists of 10 open reading frames (ORFs), designated
dcsA
to
dcsJ
. This cluster includes two ORFs encoding
d
-alanyl-
d
-alanine ligase (
dcsI
) and a putative membrane protein (
dcsJ
) as the self-resistance determinants of the producer organism, indicated by our previous work. When the 10 ORFs were introduced into DCS-nonproducing
Streptomyces lividans
66 as a heterologous host cell, the transformant acquired DCS productivity. This reveals that the introduced genes are responsible for the biosynthesis of DCS. As anticipated, the disruption of
dcsG
, seen in the DCS biosynthetic gene cluster, made it possible for the strain ATCC 11924 to lose its DCS production. We here propose the DCS biosynthetic pathway. First,
l
-serine is O acetylated by a
dcsE-
encoded enzyme homologous to homoserine
O
-acetyltransferase. Second,
O
-acetyl-
l
-serine accepts hydroxyurea
via
an
O
-acetylserine sulfhydrylase homolog (
dcsD
product) and forms
O
-ureido-
l
-serine. The hydroxyurea must be supplied by the catalysis of a
dcsB
-encoded arginase homolog using the
l
-arginine derivative,
N
G
-hydroxy-
l
-arginine. The resulting
O
-ureido-
l
-serine is then racemized to
O
-ureido-
d
-serine by a homolog of diaminopimelate epimerase. Finally,
O
-ureido-
d
-serine is cyclized to form DCS with the release of ammonia and carbon dioxide. The cyclization must be done by the
dcsG
or
dcsH
product, which belongs to the ATP-grasp fold family of protein.
Pharmacokinetics of Chloroquine and Monodesethylchloroquine in Pregnancy
Authors: Karunajeewa Harin A. , Salman Sam , Mueller Ivo , Baiwog Francisca , Gomorrai Servina , Law Irwin , Page-Sharp Madhu , Rogerson Stephen , Siba Peter , Ilett Kenneth F. , Davis Timothy M. E.
Published: January 2010

In order to determine the pharmacokinetic disposition of chloroquine (CQ) and its active metabolite, desethylchloroquine (DECQ), when administered as intermittent presumptive treatment in pregnancy (IPTp) for malaria, 30 Papua New Guinean women in the second or third trimester of pregnancy and 30 age-matched nonpregnant women were administered three daily doses of 450 mg CQ (8.5 mg/kg of body weight/day) in addition to a single dose of sulfadoxine-pyrimethamine. For all women, blood was taken at baseline; at 1, 2, 4, 6, 12, 18, 24, 30, 48, and 72 h posttreatment; and at 7, 10, 14, 28, and 42 days posttreatment. Plasma was subsequently assayed for CQ and DECQ by high-performance liquid chromatography, and population pharmacokinetic modeling was performed. Pregnant subjects had significantly lower area under the plasma concentration-time curve for both CQ (35,750 versus 47,892 μg·h/liter,
P
< 0.001) and DECQ (23,073 versus 41,584 μg·h/liter,
P
< 0.001), reflecting significant differences in elimination half-lives and in volumes of distribution and clearances relative to bioavailability. Reduced plasma concentrations of both CQ and DECQ could compromise both curative efficacy and posttreatment prophylactic properties in pregnant patients. Higher IPTp CQ doses may be desirable but could increase the risk of adverse hemodynamic effects.
Haemophilus influenzae
Clinical Isolates with Plasmid pB1000 Bearing
bla
ROB-1
: Fitness Cost and Interspecies Dissemination
Authors: San Millan Alvaro , Garcia-Cobos Silvia , Escudero Jose Antonio , Hidalgo Laura , Gutierrez Belen , Carrilero Laura , Campos Jose , Gonzalez-Zorn Bruno
Published: January 2010

Plasmid pB1000 is a mobilizable replicon bearing the
bla
ROB-1
β-lactamase gene that we have recently described in
Haemophilus parasuis
and
Pasteurella multocida
animal isolates. Here we report the presence of pB1000 and a derivative plasmid, pB1000′, in four
Haemophilus influenzae
clinical isolates of human origin. Pulsed-field gel electrophoresis showed unrelated patterns in all strains, indicating that the existence of pB1000 in
H. influenzae
isolates is not the consequence of clonal dissemination. The replicon can be transferred both by transformation and by conjugation into
H. influenzae
, giving rise to recipients resistant to ampicillin and cefaclor (MICs, ≥64 μg/ml). Stability experiments showed that pB1000 is stable in
H. influenzae
without antimicrobial pressure for at least 60 generations. Competition experiments between isogenic
H. influenzae
strains with and without pB1000 revealed a competitive disadvantage of 9% per 10 generations for the transformant versus the recipient. The complete nucleotide sequences of nine pB1000 plasmids from human and animal isolates, as well as the epidemiological data, suggest that animal isolates belonging to the
Pasteurellaceae
act as an antimicrobial resistance reservoir for
H. influenzae
. Further, since
P. multocida
is the only member of this family that can colonize both humans and animals, we propose that
P. multocida
is the vehicle for the transport of pB1000 between animal- and human-adapted members of the
Pasteurellaceae
.
Synergism between a Novel Chimeric Lysin and Oxacillin Protects against Infection by Methicillin-Resistant
Staphylococcus aureus
Authors: Daniel Anu , Euler Chad , Collin Mattias , Chahales Peter , Gorelick Kenneth J. , Fischetti Vincent A.
Published: January 2010

Staphylococcus aureus
is the causative agent of several serious infectious diseases. The emergence of antibiotic-resistant
S. aureus
strains has resulted in significant treatment difficulties, intensifying the need for new antimicrobial agents. Toward this end, we have developed a novel chimeric bacteriophage (phage) lysin that is active against staphylococci, including methicillin-resistant
S. aureus
(MRSA). The chimeric lysin (called ClyS) was obtained by fusing the N-terminal catalytic domain of the
S. aureus
Twort phage lysin with the C-terminal cell wall-targeting domain from another
S. aureus
phage lysin (phiNM3), which displayed
Staphylococcus
-specific binding. ClyS was expressed in
Escherichia coli
, and the purified protein lysed MRSA, vancomycin-intermediate strains of
S. aureus
(VISA), and methicillin-sensitive (MSSA) strains of
S. aureus in vitro
. In a mouse nasal decolonization model, a 2-log reduction in the viability of MRSA cells was seen 1 h following a single treatment with ClyS. One intraperitoneal dose of ClyS also protected against death by MRSA in a mouse septicemia model. ClyS showed a typical pattern of synergistic interactions with both vancomycin and oxacillin
in vitro
. More importantly, ClyS and oxacillin at doses that were not protective individually protected synergistically against MRSA septic death in a mouse model. These results strongly support the development of ClyS as an attractive addition to the current treatment options of multidrug-resistant
S. aureus
infections and would allow for the reinstatement of antibiotics shelved because of mounting resistance.
In Vitro
Activities of Eight Antifungal Drugs against 55 Clinical Isolates of
Fonsecaea
spp
Authors: Najafzadeh Mohammad J. , Badali Hamid , Illnait-Zaragozi Maria Teresa , De Hoog G. Sybren , Meis Jacques F.
Published: January 2010

The
in vitro
activities of eight antifungal drugs against clinical isolates of
Fonsecaea pedrosoi
(
n
= 21),
Fonsecaea monophora
(
n
= 25), and
Fonsecaea nubica
(
n
= 9) were tested. The resulting MIC
90
s for all strains (
n
= 55) were as follows, in increasing order: posaconazole, 0.063 μg/ml; itraconazole, 0.125 μg/ml; isavuconazole, 0.25 μg/ml; voriconazole, 0.5 μg/ml; amphotericin B, 2 μg/ml; caspofungin, 2 μg/ml; anidulafungin, 2 μg/ml; and fluconazole, 32 μg/ml.
Clinical Isolates of
Mycobacterium tuberculosis
in Four European Hospitals Are Uniformly Susceptible to Benzothiazinones
Authors: Pasca Maria Rosalia , Degiacomi Giulia , Ribeiro Ana Luisa de Jesus Lopes , Zara Francesca , De Mori Patrizia , Heym Beate , Mirrione Maurizio , Brerra Roberto , Pagani Laura , Pucillo Leopoldo , Troupioti Panajota , Makarov Vadim , Cole Stewart T. , Riccardi Giovanna
Published: January 2010

The new antitubercular drug candidate 2-[2-
S
-methyl-1,4-dioxa-8-azaspiro[4.5]dec-8-yl]-8-nitro-6-(trifluoromethyl)-4H-1,3-benzothiazin-4-one (BTZ043) targets the DprE1 (Rv3790) subunit of the enzyme decaprenylphosphoryl-β-
d
-ribose 2′-epimerase. To monitor the potential development of benzothiazinone (BTZ) resistance, a total of 240 sensitive and multidrug-resistant
Mycobacterium tuberculosis
clinical isolates from four European hospitals were surveyed for the presence of mutations in the
dprE1
gene and for BTZ susceptibility. All 240 strains were susceptible, thus establishing the baseline prior to the introduction of BTZ043 in clinical trials.
The NF-κB p50 Subunit Is Protective during Intestinal
Entamoeba histolytica
Infection of 129 and C57BL/6 Mice
Authors: Cho Kyou-Nam , Becker Stephen M. , Houpt Eric R.
Published: January 2010

Entamoeba histolytica
is the agent of amebic colitis. In this work we examined the intestinal NF-κB response to this parasite. Using an enzyme-linked immunosorbent assay (ELISA) and an electrophoretic mobility shift assay, we found that the NF-κB subunit p50 predominated in nuclear extracts of whole cecal tissue and of isolated crypts from mice inoculated with
E. histolytica
. p50 was protective, since C57BL/6 and 129 mice in which there was targeted deletion of this subunit were more susceptible to
E. histolytica
infection as measured by culture results, cecal parasite ELISA results, and/or histologic scores. The transepithelial electrical resistance of cecal explants from C57BL/6 and 129 p50 knockout mice decreased markedly in response to the parasite compared with the transepithelial electrical resistance of their wild-type counterparts, suggesting that a protective function of p50 was present in the epithelium itself. This work shows that NF-κB activity, particularly activity of the p50 subunit, is one factor that contributes to resistance of the gut to
E. histolytica
infection.
Contribution of
Vibrio parahaemolyticus
Virulence Factors to Cytotoxicity, Enterotoxicity, and Lethality in Mice
Authors: Hiyoshi Hirotaka , Kodama Toshio , Iida Tetsuya , Honda Takeshi
Published: January 2010

Vibrio parahaemolyticus
, one of the human-pathogenic vibrios, causes three major types of clinical illness: gastroenteritis, wound infections, and septicemia. Thermostable direct hemolysin (TDH) secreted by this bacterium has been considered a major virulence factor of gastroenteritis because it has biological activities, including cytotoxic and enterotoxic activities. Previous reports revealed that
V. parahaemolyticus
strain RIMD2210633, which contains
tdh
, has two sets of type III secretion system (T3SS) genes on chromosomes 1 and 2 (T3SS1 and T3SS2, respectively) and that T3SS1 is responsible for cytotoxicity and T3SS2 is involved in enterotoxicity, as well as in cytotoxic activity. However, the relative importance and contributions of TDH and the two T3SSs to
V. parahaemolyticus
pathogenicity are not well understood. In this study, we constructed mutant strains with nonfunctional T3SSs from the
V. parahaemolyticus
strain containing
tdh
, and then the pathogenicities of the wild-type and mutant strains were evaluated by assessing their cytotoxic activities against HeLa, Caco-2, and RAW 264 cells, their enterotoxic activities in rabbit ileal loops, and their lethality in a murine infection model. We demonstrated that T3SS1 was involved in cytotoxic activities against all cell lines used in this study, while T3SS2 and TDH had cytotoxic effects on a limited number of cell lines. T3SS2 was the major contributor to
V. parahaemolyticus
-induced enterotoxicity. Interestingly, we found that both T3SS1 and TDH played a significant role in lethal activity in a murine infection model. Our findings provide new indications that these virulence factors contribute to and orchestrate each distinct aspect of the pathogenicity of
V. parahaemolyticus
.
Yersinia pestiswith Regulated Delayed Attenuation as a Vaccine Candidate To Induce Protective Immunity against Plague
Authors: Sun Wei , Roland Kenneth L. , Kuang Xiaoying , Branger Christine G. , Curtiss Roy
Published: January 2010

Two mutant strains ofYersinia pestisKIM5+, a Δcrpmutant and a mutant with arabinose-dependent regulated delayed-shutoffcrpexpression (araCPBADcrp), were constructed, characterizedin vitro, and evaluated for virulence, immunogenicity, and protective efficacy in mice. Both strains were highly attenuated by the subcutaneous (s.c.) route. The 50% lethal doses (LD50s) of the ΔcrpandaraCPBADcrpmutants were approximately 1,000,000-fold and 10,000-fold higher than those ofY. pestisKIM5+, respectively, indicating that both strains were highly attenuated. Mice vaccinated s.c. with 3.8 × 107CFU of the Δcrpmutant developed high anti-Y. pestisand anti-LcrV serum IgG titers, both with a strong Th2 bias, and induced protective immunity against subcutaneous challenge with virulentY. pestis(80% survival) but no protection against pulmonary challenge. Mice vaccinated with 3.0 × 104CFU of thearaCPBADcrpmutant also developed high anti-Y. pestisand anti-LcrV serum IgG titers but with a more balanced Th1/Th2 response. This strain induced complete protection against s.c. challenge and partial protection (70% survival) against pulmonary challenge. Our results demonstrate that arabinose-dependent regulatedcrpexpression is an effective strategy to attenuateY. pestiswhile retaining strong immunogenicity, leading to protection against the pneumonic and bubonic forms of plague.