bluuebunny/crossref_metadata_2025 huggingface dataset:
Beneficial effect of albuterol in congenital myasthenic syndrome with epsilon‐subunit mutations
Authors: Sadeh Menachem , Shen Xin‐Ming , Engel Andrew G.
Published: June 2011

Mutations in the epsilon subunit of the acetylcholine receptor (AChR) are a common cause of congenital myasthenic syndrome (CMS). Patients are usually treated with acetylcholinesterase inhibitors and 3,4‐diaminopyridine with modest clinical benefit. We report 2 patients with CMS due to mutations in the AChR epsilon subunit. The first patient carries two heterozygous frameshift mutations, ε127ins5 and ε1293insG. The second patient is homozygous for the εC142Y mutation that curtails AChR expression to 22% of wild‐type in HEK cells. Treatment with pyridostigmine and 3,4‐diaminopyridine had a limited beneficial effect in the first patient, and the second patient became wheelchair‐bound during therapy. The additional use of albuterol produced dramatic improvement in strength and in activities of daily living in both patients. The efficacy and safety of albuterol in patients who harbor identified low‐expressor or null mutations in the epsilon or other subunits of AChR merits a well‐designed clinical trial. Muscle Nerve, 2011
Reduction of urgency severity is associated with long‐term therapeutic effect after intravesical onabotulinumtoxina injection for idiopathic detrusor overactivity
Authors: Kuo Hann‐Chorng
Published: June 2011

Aims

Intravesical onabotulinumtoxinA (BoNT‐A) injection is a promising treatment for refractory detrusor overactivity (DO). This study investigated the long‐term success rate of BoNT‐A injection for patients with idiopathic DO and its association with reduction of urgency severity.

Methods

This study was a retrospective analysis of 174 patients with idiopathic DO who received first‐time 100 U BoNT‐A injections. The patients were collected from several previous clinical trials. The therapeutic effects were classified as significant sensory effects with urgency severity score reductions of ≥2 and/or significant motor effects with cystometric bladder capacity increases of ≥25%. The treatment results based on patients' perceptions of bladder conditions and long‐term success rates were analyzed among the different therapeutic‐effect subgroups.

Results

A successful outcome was reported by 138 (79.3%) patients at 3 months. Seventy‐seven (44.3%) patients had both sensory and motor effects, 5 (2.9%) had sensory effects alone, 83 (47.7%) had motor effects alone, and 9 (5.2%) had no sensory or motor effect. All 82 patients with sensory with/without motor effects reported a successful result. In contrast, only 50 (60.2%) patients with motor effects alone reported success at 3 months. Increased cystometric bladder capacity and postvoid residual and decreased voiding efficiency were noted in patients with motor with/without sensory effects. The therapeutic results lasted significantly longer in patients with sensory with/without motor effects than those with motor effects alone.

Conclusions

Improvement of urgency severity is significantly associated with a higher success rate at 3 months and longer therapeutic duration after intravesical BoNT‐A injection for IDO. Neurourol. Urodynam. Neurourol. Urodynam. 30: 1497–1502, 2011. © 2011 Wiley Periodicals, Inc.
Racial differences in self‐reported healthcare seeking and treatment for urinary incontinence in community‐dwelling women from the EPI study
Authors: Berger Mitchell B. , Patel Divya A. , Miller Janis M. , DeLancey John O. , Fenner Dee E.
Published: June 2011

Aims

Objectives of this study are: (1) to examine the prevalence of healthcare seeking among black and white women with self‐reported urinary incontinence (UI), (2) to investigate barriers to treatment for incontinence, and (3) To investigate commonly used therapeutic modalities for UI.

Methods

This is a planned secondary analysis of responses from 2,812 black and white community‐dwelling women living in southeastern Michigan, aged 35–64 years, who completed a telephone interview concerning UI, healthcare‐seeking behaviors and management strategies. The study population was 571 subjects (278 black, 293 white) who self‐identified as having urinary incontinence.

Results

Of these women with UI, 51% sought healthcare with no statistically significant difference between the two races (53% black, 50.6% white, P = 0.64). In multivariate logistic regression analysis, a higher likelihood of seeking healthcare was associated with increased age, body mass index lower than 30 kg/m2, prior surgery for UI, having regular pelvic exams, having a doctor, and worsening severity of UI. There was no significant association between hypothesized barriers to care seeking and race. Almost 95% of the subjects identified lack of knowledge of available treatments as one barrier. Black and white women were similar in percentage use of medications and some self‐care strategies, for example, pad wearing and bathroom mapping, but black women were significantly more likely to restrict fluid intake than white women and marginally less likely to perform Kegels.

Conclusions

Black and white women seek healthcare for UI at similar, low rates. Improved patient‐doctor relationships and public education may foster healthcare seeking behavior. Neurourol. Urodynam. Neurourol. Urodynam. 30: 1442–1447, 2011. © 2011 Wiley Periodicals, Inc.
Functional characterization of a chronic cyclophosphamide‐induced overactive bladder model in mice
Authors: Boudes Mathieu , Uvin Pieter , Kerselaers Sara , Vennekens Rudi , Voets Thomas , De Ridder Dirk
Published: June 2011

Aims

To describe a new mouse model of overactive bladder (OAB) at the histological level, pain, voiding behavior, and urodynamics, while assessing the physiological state of mice.

Methods

This paper compares the pathophysiological features of mice that received intraperitoneal injections of cyclophosphamide (CYP) (40 and 80 mg/kg − body weight) every 2 days for 7 days. Specifically, the heart rate, the body temperature, and the general activity were assessed by telemetry. The abdominal sensitivity was determined with Von Frey filaments. Voiding behavior and detrusor activity were respectively quantified by urine spotting experiments and cystometry. Hematoxylin & Eosin staining was performed to detect inflammation in tissue and NGF concentration in urine was quantified.

Results

Affected mice exhibit clearly an OAB characterized by an increase in the number of voiding events and an urodynamically‐demonstrated detrusor overactivity associated with referred hyperalgesia. The injected mice displayed inflamed bladder, urothelial hyperplasia, and increased NGF concentration in urine in dose dependant manner. However, the physiological features of mice with CYP‐induced cystitis are not changed.

Conclusions

We can show that this model of chronic OAB with pain in mice fits more closely to the clinical signs of patients with OAB than the available animal models (acute and chronic) and will therefore be useful to highlight potential drug targets in genetically modified mice in the future. Neurourol. Urodynam. Neurourol. Urodynam. 30: 1659–1665, 2011. © 2011 Wiley Periodicals, Inc.
Natural hp‐BEM for the electric field integral equation with singular solutions
Authors: Bespalov Alexei , Heuer Norbert
Published: June 2011

We apply the hp ‐version of the boundary element method (BEM) for the numerical solution of the electric field integral equation (EFIE) on a Lipschitz polyhedral surface Γ. The underlying meshes are supposed to be quasi‐uniform triangulations of Γ, and the approximations are based on either Raviart‐Thomas or Brezzi‐Douglas‐Marini families of surface elements. Nonsmoothness of Γ leads to singularities in the solution of the EFIE, severely affecting convergence rates of the BEM. However, the singular behavior of the solution can be explicitly specified using a finite set of functions (vertex‐, edge‐, and vertex‐edge singularities), which are the products of power functions and poly‐logarithmic terms. In this article, we use this fact to perform an a priori error analysis of the hp ‐BEM on quasi‐uniform meshes. We prove precise error estimates in terms of the polynomial degree p, the mesh size h, and the singularity exponents. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2012
Reduced expression of transforming growth factor‐β1 and correlated elevation of interleukin‐17 and interferon‐γ in pediatric patients with chronic primary immune thrombocytopenia (ITP)
Authors: Wang Jiaan‐Der , Chang Te‐Kau , Lin Heng‐Kuei , Huang Fang‐Liang , Wang Chau‐Jong , Lee Huei‐Jane
Published: June 2011

Background

Dysregulated T helper (Th) cells are considered important in the pathophysiology of chronic primary immune thrombocytopenia (ITP). The present study investigated whether levels of Th cytokines in pediatric patients with chronic ITP were different compared with healthy controls.

Procedures

Fifty‐seven pediatric patients with chronic ITP and 28 healthy controls were enrolled. Patients were divided into three groups based on their platelet counts at the time of the study: (i) active disease <50 × 109/l (n = 23), (ii) stable disease 50–150 × 109/l (n = 23), and (iii) in remission >150 × 109/l (n = 11). Plasma concentration of Th1 [interferon gamma (INF‐γ), interleukin 2 (IL‐2)], Th2 (IL‐4, IL‐10), Th3 [transforming growth factor‐β1 (TGF‐β1)], and Th17 (IL‐17) cytokines were investigated by enzyme‐linked immunosorbent assay.

Results

IFN‐γ was increased in patients with active (P < 0.001) and stable disease (P = 0.026) when compared with controls. The IL‐17 level was significantly higher in all of the 3 patient groups. In addition, there was a positive correlation between IL‐17 and IFN‐γ levels in chronic ITP patients (r = 0.640, P < 0.001). Reduced TGF‐β1 expression was observed in patients with active (P < 0.001) and stable disease (P = 0.001) in comparison with controls. Moreover, TGF‐β1 level in patients was positively correlated with the platelet count (r = 0.355, P = 0.007).

Conclusions

Elevation of IL‐17 and IFN‐γ may be an important dysregulation of cellular immunity in pediatric patients with chronic ITP. The disease activity is associated with reduced production of TGF‐β1. Pediatr Blood Cancer 2011; 57: 636–640. © 2011 Wiley‐Liss, Inc.
Neutropenia in infants with hemolytic disease of the newborn
Authors: Blanco Esther , Johnston Donna L.
Published: June 2011

Background

This study examined the incidence, outcome and risk factors of neutropenia in infants with hemolytic disease of the newborn (HDN).

Methods

A retrospective chart review was performed on infants with HDN.

Results

Of 69 evaluable infants, 45% developed neutropenia. Only one infectious complication was recorded. In most instances the neutropenia resolved spontaneously, but in seven infants it persisted for a median of 397 days. Males were at higher risk for developing neutropenia, but severity of HDN, antibody specificity, or therapy were not significant risk factors.

Conclusions

Neutropenia is a common feature of HDN, regardless of severity of disease, treatment received, or antibody specificity. Pediatr Blood Cancer 2012; 58: 950–952. © 2011 Wiley Periodicals, Inc.
Incidence, risk factors, and outcome of pneumatosis intestinalis in pediatric stem cell transplant recipients
Authors: Korhonen Katrina , Lovvorn Harold N. , Koyama Tatsuki , Koehler Elizabeth , Calder Cassie , Manes Becky , Evans Misty , Bruce Kathryn , Ho Richard H. , Domm Jennifer , Frangoul Haydar
Published: June 2011

Background

Pneumatosis Intestinalis (PI) is a rare complication following hematopoietic stem cell transplant (HSCT). We sought to assess the incidence, risk factors, and outcome associated with PI.

Procedure

We retrospectively reviewed the incidence of PI among 178 patients who underwent allogeneic HSCT between September 1999 and February 2010.

Results

Eighteen of 178 children (10.1%) who received allogeneic HSCT developed PI at a median of 94 days (range, 11–1169) after transplant. All patients presented with either abdominal pain or distention, and half of the patients had free air on radiographs. Patients who developed PI had a significantly higher proportion of acute (83% vs. 44%, P = 0.002) and chronic graft versus host disease (GVHD; 56% vs. 18%, P < 0.001). Only 39% of patients with PI had GVHD involving the gasterointestinal track. All patients were managed conservatively without surgery. Transplant related mortality (TRM) was significantly higher in patients who developed PI compared to those who did not (OR 4.3, 95% CI: 1.3–13.1; P = 0.007), but no deaths were attributable to PI.

Conclusions

We conclude that PI is a common complication associated with treatment of GVHD after HSCT, and patients who develop PI experience higher TRM. Patients who develop PI should be managed medically. Pediatr Blood Cancer 2012; 58: 616–620. © 2011 Wiley Periodicals, Inc.
First trimester screening for intra‐uterine growth restriction and early‐onset pre‐eclampsia
Authors: Vandenberghe G. , Mensink I. , Twisk J. W. R. , Blankenstein M. A. , Heijboer A. C. , van Vugt J. M. G.
Published: June 2011

Objective

To assess first trimester placental growth factor (PlGF) and pregnancy‐associated plasma protein‐A (PAPP‐A) as screening markers for early‐onset pre‐eclampsia (PE) and intra‐uterine growth restriction (IUGR).

Methods

PlGF concentration was retrospectively measured in first trimester serum specimens of 23 cases of early‐onset PE (<34 weeks), 26 cases of IUGR (birth weight < 5th centile) and 5 controls per case. Levels were adjusted for gestational age (GA), ethnicity and smoking to obtain multiples of the expected median (MoM). Logistic regression was used to assess PlGF, PAPP‐A and maternal characteristics as potential predictors of early‐onset PE and IUGR.

Results

PlGF MoM levels were significantly lower in the early‐onset PE group (P < 0.0001) compared with controls, but not in the IUGR group. PAPP‐A MoM levels were significantly lower in the IUGR group (P < 0.01) compared with controls but not in the early‐onset PE group. PlGF significantly improved the ability of systolic blood pressure at the first prenatal visit to predict early‐onset PE [achieving a receiver‐operating characteristics curve with area under the curve (AUC) of 0.8]. Combining systolic blood pressure at the first prenatal visit and PlGF did not significantly improve the predictive ability compared with PlGF alone (AUC = 0.83).

Conclusion

Serum PlGF is an acceptable marker in first trimester screening for early‐onset PE, but a poor marker in screening for IUGR. Screening performance of serum PAPP‐A is poor for both early‐onset PE and IUGR. Copyright © 2011 John Wiley & Sons, Ltd.
Fragile X analysis of 1112 prenatal samples from 1991 to 2010
Authors: Nolin Sarah L. , Glicksman Anne , Ding Xiaohua , Ersalesi Nicole , Brown W. Ted , Sherman Stephanie L. , Dobkin Carl
Published: June 2011

Objective

To determine risks of expansion for normal, intermediate, and premutationFMR1CGG repeats.

Methods

PCR was used to compare theFMR1alleles in prenatal (chorionic villi and amniocytes) and parental samples collected from 1991 to 2010. Prenatal diagnoses were confirmed by Southern analysis.

Results

Fragile X analysis of 1112 pregnancies identified 558 normal, 106 intermediate, 216 premutation, and 232 full mutation fetuses. Of 509 maternal, intermediate, and premutation alleles, 350 (68.7%) were unstable on transmission with expansions ranging from one repeat to the full mutation. The smallest premutation alleles expanding to the full mutation were in mothers with 65 and 66 repeats. Transmissions from women with or without a family history of fragile X suggested greater instability in women from families that included full mutation expansions.

Conclusions

The maternal transmissions of alleles with 55 to 59 CGG repeats summarized here indicate that the risk for expansion to full mutation is substantially less than previous estimates for this size category. Most premutation alleles with no family history of fragile X exhibited less instability than those with a history of fragile X. Thus, lower risk estimates for full mutation expansion may be appropriate for women newly identified as premutation carriers through routine screening. Copyright © 2011 John Wiley & Sons, Ltd.
Poly(1,4‐cyclohexylenedimethylene‐1, 4‐cyclohexanedicarboxylate): analysis of parameters affecting polymerization and cis–trans isomerization
Authors: Colonna Martino , Berti Corrado , Binassi Enrico , Celli Annamaria , Fiorini Maurizio , Marchese Paola , Messori Massimo , Brunelle Daniel J.
Published: June 2011

Weatherable semicrystalline polyesters based on 1,4‐cyclohexanedimethanol, 1,4‐cyclohexanedicarboxylic acid (CHDA) or dimethyl 1,4‐cyclohexane dicarboxylate (DMCD) can be prepared under normal melt‐phase conditions, using titanium tetrabutoxide as catalyst. The effect of monomer ratio, reaction temperature and catalyst loading on the final polymer properties was studied. Under the proper polymerization conditions, poly(1,4‐cyclohexylenedimethylene‐1,4‐cyclohexanedicarboxylate) polymers with high molecular weight can be obtained. During polymerization, isomerization can occur towards the thermodynamically stable cis‐trans ratio of 34–66 mol%. Carboxylic acid end groups can catalyze the isomerization and therefore the polymerization is more critical starting from CHDA rather than DMCD. Moreover, temperature control becomes a key factor to avoid or to limit isomerization. The study of the isomerization of the different monomers permitted a better understanding of the isomerization and therefore of the polymerization process. Copyright © 2011 Society of Chemical Industry
Charge transport mechanism of graphite‐nanosheet‐loaded rubber nanocomposites
Authors: Mahmoud Waleed E , Al‐Ghamdi Ahmed A
Published: June 2011

Nitrile butadiene rubber loaded with different concentrations of thin graphite nanosheets have been successfully prepared by using a two‐roll mill. The percolation concentration of the nanocomposites was 0.5 phr. The I–V characteristic curves showed that the nanocomposites exhibited ohmic behaviour at a certain voltage and then non‐linear behaviour. The Richardson–Schottky and Poole–Frenkel models were used to investigate the reason for the space charge. The experimental data fit the Schottky model well. The conductivity as a function of temperature was also studied and the data were fitted by using the Mott relation. The Mott relation showed that as the concentration of graphite nanosheets in the rubber composite increases, the hopping distance between the graphite nanosheet layers decreases, which enhances the conductivity of the nanocomposite at low concentrations. Copyright © 2011 Society of Chemical Industry
Encapsulation and convex‐face thiozonolysis of triatomic sulfur (S3) with carbon nanotubes
Authors: Castillo Álvaro , Lee Leda , Greer Alexander
Published: June 2011

Nanotubes are a class of host cavities increasingly used to encapsulate unstable molecules, yet none have been exploited to host reactive sulfur species, such as thiozone (S3). In this paper, density functional theory and (ONIOM) calculations were used to compute single‐walled carbon nanotube (SWNT)–thiozone combinations for the inclusion of S3 into the hollow nanotube space and to rationalize when 1,2,3‐thiozonide formation can take place. Nanotube diameter selectivity for the isomerization of the C2v form of S3 to the D3h form proved to be elusive. Acyclic C2v S3 was ~6 kcal/mol more stable than cyclic D3h S3 whether it was free or encapsulated within an SWNT. 1,2,3‐Thiozonide formation took place on the convex side of nanotubes of low tube radii, such as the armchair (4,4) and (5,5) SWNTs. In terms of the reaction mode of C2v S3, the 1,3‐dipolar addition reaction was preferred compared with the [2 + 2] cycloaddition and chelotrope paths. Copyright © 2011 John Wiley & Sons, Ltd.
High glass transition and thermally stable polynorbornenes containing fluorescent dipyrene moieties via ring‐opening metathesis polymerization
Authors: Lian Wei‐Ren , Wu Han‐Yu , Wang Kun‐Li , Liaw Der‐Jang , Lee Kueir‐Rarn , Lai Juin‐Yih
Published: June 2011

A high‐glass‐transition‐temperature polynorbornene, poly(NBEDPY), containing chromophore groups was synthesized by ring‐opening metathesis polymerization (ROMP) using Grubbs' catalysts; poly(HNBEDPY) was obtained by the reduction of poly(NBEDPY). The glass transition temperatures (Tg) of poly(NBEDPY) and hydrogenated poly(HNBEDPY) were as high as 250 °C and 220 °C, respectively, because of the rigid dipyrene groups, which are higher than those of commercially available ring‐opened hydrogenated polynorbornenes (JSR ARTON®; 120–165 °C). The 10% weight‐loss temperatures of hydrogenated poly(HNBEDPY) and poly(NBEDPY) were up to 450 °C and 400 °C, respectively. A hydrogenated poly (HNBEDPY) film showed excellent transparency (over 91%). The photoluminescence emission spectra of poly(HNBEDPY) showed strong solvent‐polarity dependence, revealing that poly (HNBEDPY) underwent remarkable bathochromic shifts with an increase in solvent polarity. Poly(HNBEDPY) also showed remarkable fluorescent solvatochromism (blue in toluene, greenish yellow in dimethyl sulfoxide). The cyclic voltammogram of poly(HNBEDPY) film cast onto an indium tin oxide (ITO)‐coated glass substrate exhibited one reversible oxidation redox couple at 0.55 V versus Ag/Ag+ in acetonitrile solution. The electrochromic characteristics of poly(HNBEDPY) showed reversibility, with a color change from its green neutral form to dark red upon the application of potentials from 0 to 1.0 V. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Heterocyclic monomers via reissert chemistry
Authors: Gibson Harry W. , Rasco Melvin L. , Niu Zhenbin
Published: June 2011

An AA bisphenolic monomer (13), an AB activated fluoro‐phenolic monomer (14), and an AB2 alcohol‐diester monomer precursor (17), all based on the isoquinoline nucleus, were prepared using Reissert compound chemistry. Additionally, model reactions established the efficiency of condensation of isoquinoline Reissert compounds with dihaloalkanes, providing evidence of the potential of this reaction to produce high molecular weight polymers, which was subsequently realized. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Effect of void structure on the toughness of double network hydrogels
Authors: Nakajima Tasuku , Furukawa Hidemitsu , Tanaka Yoshimi , Kurokawa Takayuki , Gong Jian Ping
Published: June 2011

Introduction of soft filler in a hard body, which is one of the common toughening methods of hard polymeric materials, was applied for further toughening of robust double network (DN) hydrogels composed of poly(2‐acrylamido‐2‐methylpropanesulfonic acid) gels (PAMPS gels) as the first component and polyacrylamide (PAAm) as the second component. The fracture energy of the DN gels with the void structure (called void‐DN gels) became twice when the volume fraction of void was 1–3 vol % and the void diameter was much larger than the Flory radius of the PAAm chains. Such toughening was induced by wider range of internal fracture of the PAMPS network derived from partial stress concentration near void structure. Considering the mechanical tests and the dynamic light scattering results, it is implied that the absence of the load‐bearing PAAm structure inside the void is important for the toughening. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1246–1254, 2011
The nature and extent of body image concerns among surgically treated patients with head and neck cancer
Authors: Fingeret Michelle Cororve , Yuan Ying , Urbauer Diana , Weston June , Nipomnick Summer , Weber Randal
Published: June 2011

Background

The purpose of this study was to describe body image concerns for surgically treated patients with head and neck cancer and evaluate the relationship between body image concerns and quality of life outcomes.

Methods

Data were obtained from 280 patients undergoing surgical treatment for head and neck cancer. We used a cross‐sectional design and obtained data from individuals at different time points relative to initiation of surgical treatment. Participants completed the Body Image Scale, the Functional Assessment of Cancer Therapy Scale‐Head and Neck Version, and a survey designed for this study to evaluate disease‐specific body image issues, satisfaction with care regarding body image issues, and interest in psychosocial intervention.

Results

Body image concerns were prevalent in the majority of participants with 75% acknowledging concerns or embarrassment about one or more types of bodily changes at some point during treatment. Significant associations were found between body image concerns and all major domains of quality of life. Age, gender, cancer type, time since surgery, and body image variables were significantly associated with psychosocial outcomes. A clear subset of participants expressed dissatisfaction with care received about body image issues and/or indicated they would have liked additional resources to help them cope with body image changes.

Conclusions

These data provide useful information to document wide‐ranging body image difficulties for this population and provide important targets for the development of relevant psychosocial interventions. Copyright © 2011 John Wiley & Sons, Ltd.
Crystal structure of the C17/25 subcomplex from Schizosaccharomyces pombe RNA polymerase III
Authors: Ehara Haruhiko , Sekine Shun‐ichi , Yokoyama Shigeyuki
Published: June 2011

Eukaryotic RNA polymerase III (Pol III) is a multisubunit enzyme responsible for transcribing tRNA, 5S rRNA, and several small RNAs. Of the 17 subunits in Pol III, the C17 (Rpc17) and C25 (Rpc25) subunits form a stable subcomplex that protrudes from the core polymerase. In this study, we determined the crystal structure of the C17/25 subcomplex from Schizosaccharomyces pombe. The subcomplex adopts an elongated shape, and each subunit has two domains. The two subunits in the subcomplex are tightly packed and extensively interact, with a contact area of 2080 Å2. The overall conformation of S. pombe C17/25 is considerably different from the previously reported structure of C17/25 from Saccharomyces cerevisiae, with respect to the position of the C17 HRDC domain, a helix bundle essential for cell viability. In contrast, the S. pombe C17/25 structure is quite similar to those of the Pol II and archaeal counterparts, Rpb4/7 and RpoE/F, respectively, despite the low sequence similarity. A phylogenetic comparison of the C17 subunits among eukaryotes revealed that they can be classified into three groups, according to the length of the interdomain linker. S. pombe C17, as well as Rpb4 and RpoF, belongs to the largest group, with the short linker. On the other hand, S. cerevisiae C17 belongs to the smallest group, with the long linker, which probably enables the subcomplex to assume the alternative conformation.
A matching algorithm for catalytic residue site selection in computational enzyme design
Authors: Lei Yulin , Luo Wenjia , Zhu Yushan
Published: June 2011

A loop closure‐based sequential algorithm, PRODA_MATCH, was developed to match catalytic residues onto a scaffold for enzyme design in silico. The computational complexity of this algorithm is polynomial with respect to the number of active sites, the number of catalytic residues, and the maximal iteration number of cyclic coordinate descent steps. This matching algorithm is independent of a rotamer library that enables the catalytic residue to take any required conformation during the reaction coordinate. The catalytic geometric parameters defined between functional groups of transition state (TS) and the catalytic residues are continuously optimized to identify the accurate position of the TS. Pseudo‐spheres are introduced for surrounding residues, which make the algorithm take binding into account as early as during the matching process. Recapitulation of native catalytic residue sites was used as a benchmark to evaluate the novel algorithm. The calculation results for the test set show that the native catalytic residue sites were successfully identified and ranked within the top 10 designs for 7 of the 10 chemical reactions. This indicates that the matching algorithm has the potential to be used for designing industrial enzymes for desired reactions.
α‐Methylacyl‐CoA racemase expression and lethal prostate cancer in the Physicians' Health Study and Health Professionals Follow‐up Study
Authors: Barry Marc , Dhillon Preet K. , Stampfer Meir J. , Perner Sven , Ma Jing , Giovannucci Edward , Kurth Tobias , Mucci Lorelei A. , Rubin Mark A.
Published: June 2011

BACKGROUND

α‐Methylacyl‐CoA racemase (AMACR) is an enzyme that serves as a diagnostic biomarker of prostate cancer in clinical practice. Recent studies suggest that low AMACR expression is associated with biochemical recurrence and the development of fatal disease.

METHODS

We conducted a prospective cohort study among 920 men aged 47–84 years, who were diagnosed with prostate cancer in the Physicians' Health Study and the Health Professionals Follow‐up Study cohorts, and whose resected tissue specimens were available for immunohistochemical analysis. We used Cox proportional hazards regression to evaluate the association of AMACR expression with lethal prostate cancer over a 20‐year follow‐up period.

RESULTS

In total, 68 men died from prostate cancer, and an additional 18 developed bony metastases during follow‐up. We found that lower AMACR intensity was associated with higher prostate‐specific antigen levels (P = 0.003) and more advanced clinical stage (P = 0.06) at diagnosis, and a nonsignificant trend for higher risk of lethal outcomes. The hazard ratio (HR) comparing the lowest to the highest quartile of AMACR expression intensity was 1.53 ((95% CI: 0.86–2.73), P‐for‐trend across quartiles = 0.07); this trend was further attenuated after adjustment for age, Gleason score, stage, and cohort with a HR of 1.24 (95% CI: 0.69–2.22), P‐for‐trend = 0.23.

CONCLUSIONS

Low AMACR expression in primary tumor specimens was not independently associated with the development of metastatic and lethal prostate cancer after treatment over a 20‐year follow‐up period, after adjustment for important clinical covariates at diagnosis. Prostate 72:301–306, 2012. © 2011 Wiley Periodicals, Inc.
Enhanced activity of an insecticidal protein, trypsin modulating oostatic factor (TMOF), through conjugation with aliphatic polyethylene glycol
Authors: Jeffers Laura A , Shen Hongyan , Khalil Sayed , Bissinger Brooke W , Brandt Alan , Gunnoe T Brent , Roe R Michael
Published: June 2011

BACKGROUND: Trypsin modulating oostatic factor (TMOF), a decapeptide (Tyr‐Asp‐Pro‐Ala‐Pro6) isolated from the ovaries of the adult yellow fever mosquito, Aedes aegypti, regulates trypsin biosynthesis. TMOF per os is insecticidal to larval mosquitoes and a good model for the development of technologies to enhance protein insecticide activity by reduced catabolism and/or enhanced delivery to the target.

RESULTS: TFA‐TMOF‐K (TFA = trifluoro acetyl) allowed the specific conjugation of monodispersed, aliphatic polyethylene glycol (PEG) to the amino group of lysine‐producing TMOF‐K‐methyl(ethyleneglycol)7‐O‐propionyl (TMOF‐K‐PEG7P). The addition of lysine to TMOF reduced its per os larval mosquitocidal activity relative to the parent TMOF, but conjugation of TMOF‐K with methyl(ethyleneglycol)7‐O‐propionyl increased its toxicity 5.8‐ and 10.1‐fold above that of TMOF and TMOF‐K for Ae. aegypti. Enhanced insecticidal activity was also found for larval Ae. albopictus and for neonates of Heliothis virescens and Heliocoverpa zea. Only TMOF‐K was found by MS/MS in the hemolymph for H. virescens fed on TMOF‐K‐PEG7P. No TMOF, TMOF‐K or PEGylated TMOF‐K was detected in the hemolymph after topical applications.

CONCLUSIONS: This research suggests that aliphatic PEG polymers can be used as a new method for increasing the activity of insecticidal proteins. Copyright © 2011 Society of Chemical Industry
Effect of amphotericin B nanodisks on plant fungal diseases
Authors: Pérez‐de‐Luque Alejandro , Cifuentes Zuny , Beckstead Jennifer A , Sillero Josefina C , Ávila Carmen , Rubio Josefa , Ryan Robert O
Published: June 2011

BACKGROUND: The development of water‐soluble nanodevices extends the potential use of compounds developed for other purposes (e.g. antifungal drugs or antibiotics) for applications in agriculture. For example, the broad‐spectrum, water‐insoluble, macrolide polyene antibiotic amphotericin B (AMB) could be used to inhibit phytopathogenic fungi. A new formulation embedding AMB in nanodisks (NDs) enhances antibiotic solubility and confers protection against environmental damage. In the present study, AMB‐NDs were tested for efficacy against several phytopathogenic fungi in vitro and on infected living plants (chickpea and wheat).

RESULTS: Compared with AMB in dimethylsulfoxide (DMSO), AMB‐NDs increased the sensitivity of several fungal species to this antimycotic in vitro. Sensitivity varied with fungal species as well as with the forma specialis. Phytophthora cinnamomi, previously reported as insensitive to other polyene antimycotics, remained unaffected at the doses examined. Some effect against disease symptoms were obtained with AMB‐NDs against fusarium wilt in chickpea, whereas the results were highly variable in wheat, depending on both the species and treatment regimen.

CONCLUSION: The results confirm that formulation of AMB into ND increases its effectiveness against phytopathogenic fungi in vitro, opening the possibility for its use on infected plants in the field. Copyright © 2011 Society of Chemical Industry
Baseline susceptibilities of B‐ and Q‐biotype Bemisia tabaci to anthranilic diamides in Arizona
Authors: Li Xianchun , Degain Benjamin A , Harpold Virginia S , Marçon Paula G , Nichols Robert L , Fournier Alfred J. , Naranjo Steven E , Palumbo John C , Ellsworth Peter C
Published: June 2011

BACKGROUND: Development of pyriproxyfen and neonicotinoid resistance in the B‐biotype whitefly and recent introduction of the Q biotype have the potential to threaten current whitefly management programs in Arizona. The possibility of integrating the novel anthranilic diamides chlorantraniliprole and cyantraniliprole into the current program to tackle these threats largely depends on whether these compounds have cross‐resistance with pyriproxyfen and neonicotinoids in whiteflies. To address this question, the authors bioassayed a susceptible B‐biotype strain, a pyriproxyfen‐resistant B‐biotype strain, four multiply resistant Q‐biotype strains and 16 B‐biotype field populations from Arizona with a systemic uptake bioassay developed in the present study.

RESULTS: The magnitude of variations in LC50 and LC99 among the B‐biotype populations or the Q‐biotype strains was less than fivefold and tenfold, respectively, for both chlorantraniliprole and cyantraniliprole. The Q‐biotype strains were relatively more tolerant than the B‐biotype populations. No correlations were observed between the LC50 (or LC99) values of the two diamides against the B‐ and Q‐biotype populations tested and their survival rates at a discriminating dose of pyriproxyfen or imidacloprid.

CONCLUSION: These results indicate the absence of cross‐resistance between the two anthranilic diamides and the currently used neonicotinoids and pyriproxyfen. Future variation in susceptibility of field populations to chlorantraniliprole and cyantraniliprole could be documented according to the baseline susceptibility range of the populations tested in this study. Copyright © 2011 Society of Chemical Industry
Tolerance of two Bifora radians Bieb populations to ALS inhibitors in winter wheat
Authors: Mennan Husrev , Streibig Jens C , Ngouajio Mathieu , Kaya Emine
Published: June 2011

BACKGROUND: Bifora radians, an annual weed in winter wheat, is distributed mainly in the Mediterranean area, Asia Minor and the Caucasus. It infests winter‐sown crops of the Central Anatolia and Middle Black Sea regions of Turkey. Field experiments in heavily B. radians‐infested fields were conducted over 3 years in Samsun, Turkey, to determine the response of B. radians to ALS‐inhibiting herbicides, because growers had complained of a decrease in herbicide effect.

RESULTS: The efficacy of ALS inhibitors on a putatively tolerant population sprayed annually with ALS inhibitors and an adjacent allegedly sensitive population was estimated at the ED50 and ED90 response levels. The recommended rates of herbicides controlled 90% of the weed (ED90) in the sensitive population at the early stage of B. radians development, but not in the tolerant population. The relative potencies (EDx(tolerant)/EDx(sensitive)) of herbicides on the two populations were estimated by assuming years as being random effects. The relative potency was on average about 1.7, irrespective of the EDx levels.

CONCLUSION: Although the relative potencies were not large, they were large enough to be noted by growers. In field experiments it would be important to establish tools demonstrating when farmers recognise loss of herbicide efficacy. There has been no indication of evolution of resistant biotypes so far, but continuous spraying favours biotypes with increased levels of tolerance. Copyright © 2011 Society of Chemical Industry
Studies of lithium argyrodite solid electrolytes for all‐solid‐state batteries
Authors: Rao R. P. , Adams S.
Published: June 2011

Rechargeable all‐solid‐state lithium Li‐ion batteries (AS‐LIBs) are attractive power sources for electrochemical applications; due to their potentiality in improving safety and stability over conventional batteries with liquid electrolytes. AS‐LIBs require a Li‐fast ion conductor (FIC) as the solid electrolyte. Finding a solid electrolyte with high ionic conductivity and compatibility with other battery components is a key factor in building high performance AS‐LIBs. There have been numerous studies, e.g., on lithium rich sulfide glasses as solid electrolytes. However, the limited current density remains a major obstacle in developing competitive batteries based on the known solid electrolytes. Here we prepare argyrodite‐type Li6PS5X (X = Cl, Br, I) using mechanical milling followed by annealing. XRD characterization reveals the formation and growth of Li6PS5X crystals in samples under varying annealing conditions. For Li6PS5Cl an ionic conductivity of the order of 10−4 S/cm is reached at room temperature, which is close to the Li mobility in conventional liquid electrolytes (LiPF6 in various carbonates) and well suitable for AS‐LIBs.
Structural, electrical, and surface morphological characteristics of rapidly annealed Pt/Ti Schottky contacts to n‐type InP
Authors: Reddy V. Rajagopal , Reddy D. Subba , Naik S. Sankar , Choi C.‐J.
Published: June 2011

We have investigated the electrical and structural properties of Pt/Ti metallization scheme on n‐type InP as a function of annealing temperature using current–voltage (I–V), capacitance–voltage (C–V), Auger electron spectroscopy (AES), and X‐ray diffraction (XRD) measurements. Measurements showed that barrier height of as‐deposited Pt/Ti Schottky contact is 0.62 eV (I–V) and 0.76 eV (C–V). Experimental results indicate that high‐quality Schottky contact with barrier height and ideality factor of 0.66 eV (I–V), 0.80 eV (C–V), and 1.14 can be achieved after annealing at 400 °C for 1 min in N2 atmosphere. Further, it is observed that the barrier height slightly decreases to 0.55 eV (I–V) and 0.71 eV (C–V) after annealing at 500 °C. Norde method is also employed to calculate the barrier height of Pt/Ti Schottky contacts. The obtained values are in good agreement with those obtained by I–V measurements. These results indicate that the optimum annealing temperature for the Pt/Ti Schottky contact is 400 °C. According to AES and XRD analysis, the formation of indium phases at the Pt/Ti/n‐InP interface could be the reason for the increase of Schottky barrier height (SBH) after annealing at 400 °C. Results also showed the formation of phosphide phases at the interface. This may be the reason for the decrease in the barrier height after annealing at 500 °C. The AFM results showed that the overall surface morphology of Pt/Ti Schottky contact is reasonably smooth.
Soft X‐ray induced oxidation on acrylic acid grafted luminescent silicon quantum dots in ultrahigh vacuum
Authors: Chao Yimin , Wang Qi , Pietzsch Annette , Hennies Franz , Ni Hongjun
Published: June 2011

Water soluble acrylic acid grafted luminescent silicon quantum dots (Si‐QDs) were prepared by a simplified method. The resulting Si‐QDs dissolved in water and showed stable strong luminescence with peaks at 436 and 604 nm. X‐ray photoelectron spectroscopy (XPS) was employed to examine the surface electronic states after the synthesis. The co‐existence of the Si2p and C1s core levels infers that the acrylic acid has been successfully grafted on the surface of silicon quantum dots. To fit the Si2p spectrum, four components were needed at 99.45, 100.28, 102.21 and 103.24 eV. The first component at 99.45 eV (I) was assigned to Si–Si within the silicon core of the Si‐QDs. The second component at 100.28 eV (II) was from Si–C. The third at 102.21 eV (III) was a sub‐oxide state and the fourth at 103.24 eV (IV) was from SiO2 at Si‐QDs surface. With an increase in exposure to soft X‐ray photons, the intensity ratio of the two peaks within the Si2p region A and B increased from 0.5 to 1.4 while the peak A intensity decreased, and eventually a steady state was reached. This observation is explained in terms of photon‐induced oxidation taking place within the surface dangling bonds. As the PL profile for Si‐QDs is influenced by the degree of oxidation within the nanocrystal structure, the inducement of oxidation by soft X‐rays will play a role in the range of potential applications where such materials could be used – especially within biomedical labelling.
Low‐energy conductance of graphene nanoribbons
Authors: Zhang Yong , Han Mei
Published: June 2011

Within the nearest‐neighbor tight‐binding theory, the low‐energy conductance of graphene nanoribbons (GNRs) has been numerically calculated by using the Green's function method. The effects of the coupling between the GNRs and the electrodes on conductance oscillations of GNRs have been investigated. It is shown that the conductance oscillations appear at strong coupling. It is interesting to find that, on the first conductance step, all GNRs have only one quasiperiodic conductance oscillation; on the second conductance step, the zigzag edge GNRs and semiconducting armchair edge GNRs have two quasiperiodic conductance oscillations, i.e., a rapid conductance oscillation over a slow fluctuation background, while the metallic armchair edge GNRs have only one conductance oscillation. The mechanism underlying the origin of the conductance oscillations has been revealed.
Electronic and transport properties of disordered transition‐metal alloys
Authors: Ködderitzsch D. , Lowitzer S. , Staunton J. B. , Ebert H.
Published: June 2011

We present a first‐principles approach to describe electronic transport of disordered alloys in a material specific way. The electronic structure is represented in terms of the relativistic multiple scattering KKR‐Green function. Disorder with possible inclusion of short‐ranged order effects is taken into account by the coherent‐potential approximation or its non‐local formulation. A salient feature of the presented method is the possibility to combine it with a linear response Kubo framework, allowing for a detailed investigation of many transport phenomena which are of immediate relevance for applications in which electrons and/or their spin are manipulated. This is illustrated by several examples and developments, among them the description of the residual resistivity of K‐state‐ and ferromagnetic alloys. Inclusion of relativistic effects by using the Dirac‐formalism represents the basis to deal with the anomalous Hall effect and to derive a relativistic spin‐projection scheme for currents.
Simulating the organic‐molecule/metal interface TCNQ/Au(111)
Authors: Martínez José I. , Abad Enrique , Flores Fernando , Ortega José
Published: June 2011

A density functional calculation is performed to analyze the tetracyanoquinodimethane (TCNQ)/Au(111) interface, including the effect of the molecular charging energy on the transport gap. We find that the adsorbed TCNQ molecules are bent so that the edge N atoms are closer to the Au(111) surface. Theoretical scanning tunneling microscopy (STM) imaging is carried out and compared with the experimental STM for the TCNQ/Au(111) self‐assembled structure, finding good agreement, and validating the interface geometry obtained in our calculations. We show that the alignment between the metal and the organic levels is controlled by the charge transfer between the two materials and the dipole created in the molecule because of its deformation when adsorbed in Au(111). The calculated transport gap is 3.1 eV.
Where science fiction meets reality? With oxide semiconductors!
Authors: Fortunato E. , Martins R.
Published: June 2011

Transparent electronics is today one of the most advanced topics for a wide range of device applications, where the key components are wide band gap semiconductors, where oxides of different origin play an important role, not only as passive components but also as active components similar to what we observe in conventional semiconductors. As passive components they include the use of these materials as dielectrics for a wide range of electronic devices and also as transparent electrical conductors for use in several optoelectronic applications, such as liquid crystal displays, organic light emitting diodes, solar cells, optical sensors etc. As active materials, they exploit the use of truly electronic semiconductors where the main emphasis is being put on transparent thin film transistors, light emitting diodes, lasers, ultraviolet sensors and integrated circuits among others.

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(© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Triptolide Down‐regulates COX‐2 Expression and PGE2 Release by Suppressing the Activity of NF‐κB and MAP kinases in Lipopolysaccharide‐treated PC12 Cells
Authors: Geng Yu , Fang Marong , Wang Jing , Yu Haiyan , Hu Zhiying , Yew David T. , Chen Wei
Published: June 2011

As an active compound extracted from the Chinese herb Tripterygium wilfordii, triptolide (TP) was demonstrated to have potent antiinflammatory and immunosuppressive properties in previous studies. Recently, it has been shown that TP prevented the loss of dopaminergic neurons in the substantia nigra of rats in a model of Parkinson's disease, but little is known about the precise neuroprotective mechanism of TP. This study was designed to elucidate whether the neuroprotective effect of TP is partially based on its direct inhibition of inflammatory molecules by investigating the effects of TP on the expression of cyclooxygenase (COX)‐2 and prostaglandin E2 (PGE2) related to the nuclear factor (NF)‐κB pathway in lipopolysaccharide (LPS)‐stimulated PC12 cells. The activation of related upstream molecules such as NF‐κB, P38, extracellular signal‐regulated kinase (ERK)1/2, and beta‐alanyl‐alpha‐ketoglutarate transaminase (AKT), in PC12 cells were investigated by real time polymerase chain reaction (PCR), western blotting and enzyme‐linked immunosorbent assay (ELISA). Our results showed that TP directly inhibited the expression of both mRNA and protein of COX‐2 (p < 0.01), decreased PGE2 production (p < 0.01) in a dose‐dependent manner, down‐regulated NF‐κB activity (p < 0.01), and significantly inhibited the phosphorylation of p38, ERK1/2 (p42/p44) and AKT in PC12 cells after LPS challenge. This suggests that the neuroprotective effects of TP may be partially mediated by direct inhibition of the expression of COX‐2, activation of NF‐κB, and phosphorylation of p38, ERK1/2 (p42/p44) and AKT proteins of neuronal cells. Copyright © 2011 John Wiley & Sons, Ltd.