bluuebunny/crossref_metadata_2025 huggingface dataset:
Post‐discharge hospital utilization among adult medical inpatients with depressive symptoms
Authors: Mitchell Suzanne E. , Paasche‐Orlow Michael K. , Forsythe Shaula R. , Chetty Veerappa K. , O'Donnell Julie K. , Greenwald Jeffrey L. , Culpepper Larry , Jack Brian W.
Published: June 2010

BACKGROUND:

Little evidence exists to determine whether depression predicts hospital utilization following discharge among adult inpatients on a general medical service.

OBJECTIVE:

We aimed to determine whether a positive depression screen during hospitalization is significantly associated with an increased rate of returning for hospital services.

DESIGN:

A secondary analysis was performed using data from 738 English‐speaking, hospitalized adults from the Project RED randomized controlled trial (clinicaltrials.gov Identifier: NCT00252057) conducted at an urban academic safety‐net hospital.

MEASUREMENTS:

We used the nine‐item Patient Health Questionnaire (PHQ‐9) depression screening tool to identify patients with depressive symptoms. The primary endpoint was hospital utilization, defined as the number of emergency department (ED) visits plus readmissions within 30 days of discharge. Poisson regression was used to control for confounding variables.

RESULTS:

Of the 738 subjects included in the analysis, 238 (32%) screened positive for depressive symptoms. The unadjusted hospital utilization within 30 days of discharge was 56 utilizations per 100 depressed patients compared with 30 utilizations per 100 non‐depressed patients, incident rate ratio (IRR) (confidence interval [CI]), 1.90 (1.51–2.40). After controlling for potential confounders, a higher rate of post‐discharge hospital utilization was observed in patients with depressive symptoms compared to patients without depressive symptoms (IRR [CI], 1.73 [1.27–2.36]).

CONCLUSIONS:

A positive screen for depressive symptoms during an inpatient hospital stay is associated with an increased rate of readmission within 30 days of discharge in an urban, academic, safety‐net hospital population. Journal of Hospital Medicine 2010. © 2010 Society of Hospital Medicine.
Deficiency of telomerase activity aggravates the blood–brain barrier disruption and neuroinflammatory responses in a model of experimental stroke
Authors: Zhang Bei , Chen Lei , Swartz Karin R. , Bruemmer Dennis , Eum Sung Yong , Huang Wen , Seelbach Melissa , Choi Yean Jung , Hennig Bernhard , Toborek Michal
Published: June 2010

Epidemiology and genetic studies indicate that patients with telomere length shorter than average are at higher risk of dying from heart disease or stroke. Telomeres are located at the ends of eukaryotic chromosomes, which demonstrate progressive length reduction in most somatic cells during aging. The enzyme telomerase can compensate for telomere loss during cell replication. The present study sought to investigate the contribution of telomerase to stroke and blood–brain barrier (BBB) dysfunction. Telomerase reverse transcriptase knockout (TERT−/−) mice and littermate controls with normal TERT expression were subjected to a 24‐hr permanent middle cerebral artery occlusion (pMCAO). The stroke outcomes were assessed in terms of neurological scores and infarct volumes. In addition, we evaluated oxidative stress, permeability across the BBB, and integrity of tight junctions in brain microvessels. Neurological testing revealed that TERT−/− mice showed enhanced deficits compared with controls. These changes were associated with a greater infarct volume. The expression of tight junction protein ZO‐1 decreased markedly in ischemic hemispheres of TERT−/− mice. The brain microvessels of TERT−/− mice also were more susceptible to oxidative stress, revealing higher superoxide and lower glutathione levels compared with mice with normal TERT expression. Importantly, TERT deficiency potentiated the production of inflammatory mediators, such as tumor necrosis factor‐α, interleukin‐1β, and intercellular adhesion molecule‐1, in the ischemic hemispheres of mice with pMCAO. Our study suggests that TERT deficiency can predispose to the development of stroke in an experimental model of this disease. © 2010 Wiley‐Liss, Inc.
Conformational evolution of TFSI− in protic and aprotic ionic liquids
Authors: Martinelli Anna , Matic Aleksandar , Johansson Patrik , Jacobsson Per , Börjesson Lars , Fernicola Alessandra , Panero Stefania , Scrosati Bruno , Ohno Hiroyuki
Published: June 2010

We here report on the conformational evolution of the bis(trifluoromethanesulfonyl)imide anion (TFSI−) in protic and aprotic TFSI−‐based ionic liquids as a function of temperature. The investigation is performed by Raman spectroscopy in the spectral ranges 240‐380 cm−1 and 715‐765 cm−1, where the interference from bands due to the cations is negligible. The contribution from each TFSI− conformation, i.e. the cisoid (C1) and the transoid (C2), is quantified in order to estimate the enthalpy of conformational change, ΔH, which is found to be in the range 3.4–7.3 kJ/mol in the liquid state. Conformational information is for the first time determined from the 740 cm−1 band, which previously mainly has been used as an indicator of ion‐ion interactions. The similarity in ΔH values obtained from the two spectral ranges demonstrates the validity of using also the 740 cm−1 band for the quantification of the TFSI conformational evolution. Copyright © 2010 John Wiley & Sons, Ltd.
Pressure‐induced anomalous phase transformation in nano‐crystalline dysprosium sesquioxide
Authors: Sharma Nita Dilawar , Singh Jasveer , Dogra Sugandha , Varandani D. , Poswal Himanshu Kumar , Sharma S. M. , Bandyopadhyay A. K.
Published: June 2010

The phase transformation in nano‐crystalline dysprosium sesquioxide (Dy2O3) under high pressures is investigated using in situ Raman spectroscopy. The material at ambient was found to be cubic in structure using X‐ray diffraction (XRD) and Raman spectroscopy, while atomic force microscope (AFM) showed the nano‐crystalline nature of the material which was further confirmed using XRD. Under ambient conditions the Raman spectrum showed a predominant cubic phase peak at 374 cm−1, identified as Fg mode. With increase in the applied pressure this band steadily shifts to higher wavenumbers. However, around a pressure of about 14.6 GPa, another broad band is seen to be developing around 530 cm−1 which splits into two distinct peaks as the pressure is further increased. In addition, the cubic phase peak also starts losing intensity significantly, and above a pressure of 17.81 GPa this peak almost completely disappears and is replaced by two strong peaks at about 517 and 553 cm−1. These peaks have been identified as occurring due to the development of hexagonal phase at the expense of cubic phase. Further increase in pressure up to about 25.5 GPa does not lead to any new peaks apart from slight shifting of the hexagonal phase peaks to higher wavenumbers. With release of the applied pressure, these peaks shift to lower wavenumbers and lose their doublet nature. However, the starting cubic phase is not recovered at total release but rather ends up in monoclinic structure. The factors contributing to this anomalous phase evolution would be discussed in detail. Copyright © 2010 John Wiley & Sons, Ltd.
Effects of solid substrate on the SERS‐based immunoassay: a comparative study
Authors: Song Chunyuan , Wang Zhuyuan , Yang Jing , Zhang Ruohu , Cui Yiping
Published: June 2010

A comparative study of the solid substrates used in surface‐enhanced Raman scattering (SERS) based immunoassay is made in this paper. Five different substrates were prepared and divided into two groups with and without SERS activity. They are (1) a poly‐L‐lysine slide, (2) a glutaraldehyde (GA)‐aminosilane slide, (3) a substrate assembled with silver nanoparticles, (4) a substrate assembled with silver nanoparticles and functionalized with GA–aminosilane and (5) a substrate assembled with gold nanoparticles, of which the first two are substrates are without SERS activity and the latter three are with SERS activity because of the existence of the metallic nanoparticles. The SERS experimental results show that the immunoassay performed on an SERS‐active substrate is more effective than that employing the inactive substrate. Among the inactive substrates, the GA–aminosilane slide with a better ability for antibody immobilization leads to a more sensitive immunoassay than the poly‐L‐lysine slide. Moreover, for SERS‐based immunoassay, the substrate with assembled silver nanoparticles has an advantage of higher SERS enhancement capacity over the substrate assembled with gold nanoparticles. This work indicates that SERS‐active substrates play important and positive roles in sensitive SERS‐based immunoassay. Copyright © 2010 John Wiley & Sons, Ltd.
Local recurrence in the pectoralis muscles following modified radical mastectomy for carcinoma
Authors: Scanlon Edward F.
Published: June 2010

Local recurrence following treatment of carcinoma of the breast is usually associated with systemic metastases. However, there are some cases in which local disease is the only manifestation of recurrence, and long‐term survival can be achieved in these patients with aggressive treatment. Ten cases of apparent isolated metastasis in the pectoralis muscle following modified radical mastectomy are presented and good results were obtained in some cases utilizing surgery or x‐ray therapy or a combination. It is worth noting that reconstruction would not have interefered with the detection of these recurrences, if the implant had been placed under the muscle.
Effect of dietary fiber on intestinal transit times in operated patients with familial polyposis
Authors: Daly John M. , Miller Helen H. , Besser Pamela , Groshen Susan , Decosse Jerome J.
Published: June 2010

The effect of dietary fiber supplementation on whole gut transit time in the absence of an intact large bowel is not known. To address this question, 39 patients who had undergone a total colectomy and ileorectal anastamosis for familial polyposis were studied. Treatment arms in a controlled chemoprevention trial consisted of a placebo low‐fiber supplement (2 g fiber/day) with or without vitamins or a high‐fiber bran supplement (22 g fiber/day) with vitamins. Whole gut transit time was measured by an oral carmine marker, which was administered before and 4–6 weeks after beginning the fiber supplement. Pretreatment median whole gut transit time was 9.7 ± 9.1 hr (interquartile range; IQR), and the mean daily frequency of bowel movements was four ± two (IQR). After introduction of the treatment fiber, the median intestinal transit in the low‐fiber group (n=26) was 8.5 ± 6.7 hr (IQR), and in the high‐fiber group (n=13) median transit was 8.0 ± 6.8 hr (IQR). There was no difference in the final transit times, nor between the initial and subsequent measurements between the groups. Addition of dietary fiber increased slightly the frequency of bowel movements to a median of six per day. These results indicate that dietary fiber does not affect transit in the stomach and small intestine.
Erythropoietin production by macrophages in the regenerating liver
Authors: Naughton Gail K. , Naughton Brian A. , Gordon A. S.
Published: June 2010

The site of erythropoietin (Ep) production and/or storage in the rat liver was determined. A guinea pig anti‐Ep was produced against purified rat Ep (64,096 ± 4J064 IU/mg). This antibody was found to be highly specific using rocket immunoelectrophoresis, Ouchterlony gel diffusion methods, and immunoprecipitin reactions as well as Ep neutralization tests (capable of completely neutralizing up to 2,000 IU Ep/mg). This anti‐Ep was labeled with either fluorescein for light microscopic study or ferritin for electron microscopy. Kupffer cells showed varying degrees of labeling after hepatectomy alone or hepatectomy combined with nephrectomy and/or hypoxia. Greatest labeling was seen in Kupffer cells of rats that were nephrectomized 48 hr posthepatectomy and kept at ambient pressure. No labeling of hepatocytes or vascular and bile duct endothelium was noted.
Localization of intraperitoneal xenografts of human colon cancer by radiolabeled anti‐CEA antibodies
Authors: Duda Rosemary B. , Wong Jeffrey Y. C. , Paxton Raymond J. , Beatty Barbara G. , Williams Lawrence E. , Shively John E. , Beatty J. David
Published: June 2010

An intraperitoneal xenograft tumor model was developed in the nude mouse to represent advanced colorectal disease in the human patient. Intraperitoneal (ip) and subcutaneous (sc) tumor xenografts were successfully localized by indium 111‐labeled anti‐carcinoembryonic antigen monoclonal antibodies (Indacea) administered intravenously (IV) or in‐traperitoneally (IP). In the sc model, tumor uptake (% injected dose per g of tumor tissue—%lD/g) was significantly improved at 72 hours postin‐jection when Indacea was administered IP (44.01 ± 1.94 vs. 33.74 ± 0.87, P<0.005). In the ip model, tumor uptake at 72 hours was improved with IP Indacea (28.23 ± 5.42 vs. 19.36 ± 5.50, P<0.01) and the tumor to blood ratio was significantly improved for IP Indacea (17.83 ± 2.95 vs. 8.45 ± 1.38, P<0.01). Tumor mass was not a contributing factor in these differences. This study demonstrates that ip xenografts can be successfully imaged using radiolabeled antibodies and that the IP route of administration results in better tumor uptake of the antibody in ip lesions.
Thyroid carcinoma infiltrating the trachea: Clinical, histologic, and morphometric analyses
Authors: Nomori Hiroaki , Kobayashi Koichi , Ishihara Tsuneo , Torikata Chikao , Hosada Yasuhiro , Ozaki Osamu , Ito Kunihiko
Published: June 2010

Forty‐five patients with papillary or follicular thyroid carcinomas with tracheal infiltration were examined by clinical, histologic, and morphometric analyses. Twenty‐four patients with completely encapsulated carcinomas (encapsulated cases) and 26 patients with carcinomas confining within the thyroid capsule (nonencapsulated cases) were examined as controls. Patients with tracheal infiltration were significantly more often male and older than the patients without (P<0.01 and P<0.05, respectively). The histologic grade of differentiation did not correlate with tracheal infiltration. The nuclear area of tumor cells was significantly larger in the cases with tracheal infiltration than in the cases without (P<0.01). In 12 recurrent cases with tracheal infiltration, the nuclear area of recurrent tumours was significantly larger than those of their own primary tumors (P<0.01). These results confirm that thyroid carcinomas with tracheal infiltration were more frequent in male and older patients and had more significant nuclear atypia than the tumors without tracheal infiltration.
Localization of small liver tumors
Authors: Li Guo‐Hui , Li Jin‐Qing
Published: June 2010

Thirty‐six patients with small liver tumor were diagnosed by α‐fetoprotein (AFP); sonography, and computed tomography (CT), and underwent he‐patectomy. The pathological types included 23 hepatocelluler carcinoma (HCC), 11 hepatic cavernous hemangioma, and 2 secondary liver cancer. In 22 patients, the tumor nodules were located in the right lobe and 14 cases in the left lobe. The diagnostic accuracy rate of CT was 100% for HCC and secondary liver cancer, but for hepatic cavernous hemangioma it was only 72.2%. However, the accuracy rate of sonography was as high as 81.8% for hepatic cavernous hemangioma and only 60.4% for liver malignancies. The positive rate of AFP for the HCC patients of this series was only 66.6%. The method of intraoperative detection of small liver tumor is introduced, if the tumor was invisible grossly or nonpalpable during exploratory laparotomy. In the series, 7 cases in whom the right lobe lesion was too small to be located by routine manual examination during exploratory laparotomy were detected by this method, and all small liver tumors were resected successfully.
Establishment and characterization of human gastric and colonic xenograft lines resistant to CPT‐11 (A new derivative of camptothecin)
Authors: Nagai Satoshi , Yamauchi Masaji , Andoh Toshiwo , Nishizawa Miwako , Satta Tetsuya , Kodera Yasuhiro , Kondou Ken , Akiyama Seiji , Ito Katsuki , Takagi Hiroshi
Published: June 2010

CPT‐11‐resistant human gastric and colonic xenograft lines were established by direct intratumoral injection of CPT‐11 into subcutaneous SC‐1‐NU and CC‐2‐NU tumors in nude mice once a week for 10 months. The resistance of these xenograft lines to CPT‐11 was confirmed by growth inhibition rate, to be 36.3% and 45.4%, respectively, compared to each parent cell line. DNA topoisomerase I activity of the nuclear extracts of SC‐1‐NU/CPT‐11 and CC‐2‐NU/CPT‐11, as assayed by relaxation of supercoiled DNA Col‐E1, was significantly less than those of the parent lines. The cellular levels of topoisomerase I in those resistant lines measured by Western blot analysis were 0.57‐ and 0.79‐fold lower than those of the parental lines, respectively. However, the activity of DNA topoisomerase II of those resistant cell lines assayed by decatenation of kinetoplast DNA was higher than that of the parental lines and the cellular levels of topoisomerase II in the resistant lines measured by Western blot analysis were 10.8‐ and 8.1‐fold higher than those of the parent lines. Intracellular accumulation of CPT‐11 in CPT‐11‐resistant tumors was not changed as compared to that of the parental lines, but hydrolysis of CPT‐11 to more active SN‐38 was reduced in the resistant tumors.
Ionic liquid for single‐drop microextraction followed by high‐performance liquid chromatography‐ultraviolet detection to determine carbonyl compounds in environmental waters
Authors: Liu Qingyang , Liu Yanju , Chen Shunzong , Liu Qingjun
Published: June 2010

A sensitive method based on ionic liquid for single‐drop liquid microextraction coupled with HPLC‐UV was developed for the determination of carbonyl compounds in environmental waters using 1‐octyl‐3‐methylimidazolium hexafluorophosphate [C8min][PF6] as extraction solvent and 2,4‐dinitrophenylhydrazine as derivatizing agent. The extraction parameters affecting the enrichment factors such as solvent volume, pH, extraction time and salt concentration were investigated. A homemade funnel form polytetrafluoroethylene sleeve was fixed at the tip of the syringe needle and this allowed the use of 10 μL drop of ionic liquid for direct immersion extraction. Under the optimal conditions, the remarkable enrichment factors up to 150‐fold were obtained depending on the target analytes. The method has been validated when rectilinear relationship was obtained between the concentrations of analytes and peak area in the range of 5–100 ng/mL, the correlation coefficients were from 0.995 to 0.998, and the limit of detection was in the range of 0.04–2.03 ng/mL. The method was applied to monitor the concentration of carbonyl compounds in environmental waters with spiked recovery in the range of 84.2–106.9%.
Biointeraction analysis of carbamazepine binding to α1‐acid glycoprotein by high‐performance affinity chromatography
Authors: Xuan Hai , Joseph K. S. , Wa Chunling , Hage David S.
Published: June 2010

Interactions of the drug carbamazepine with the serum protein α1‐acid glycoprotein (AGP) were examined by high‐performance affinity chromatography. Frontal analysis studies with an immobilized AGP column and control column indicated carbamazepine had both low‐affinity interactions with the support and high‐affinity interactions with AGP. When a correction was made for binding to the support, the association equilibrium constant measured at pH 7.4 and 37°C for carbamazepine with AGP was 1.0 (±0.1)×105 M−1, with values that ranged from 5.1 to 0.58×105 M−1in going from 5 to 45°C. It was found in competition studies that these interactions were occurring at the same site that binds propranolol on AGP. Temperature studies indicated that the change in enthalpy was the main driving force for the binding of carbamazepine to AGP. These results provide a more complete picture of how carbamazepine binds to AGP in serum. This report also illustrates how high‐performance affinity chromatography can be used to examine biological interactions and drug–protein binding in situations in which significant interactions for an analyte are present with both the chromatographic support and an immobilized ligand.
New definitions of extended‐spectrum β‐lactamase conferring worldwide emerging antibiotic resistance
Authors: Lee Jung Hun , Bae Il Kwon , Hee Lee Sang
Published: June 2010

Although there is no consensus of the precise definition of ESBL, three kinds of ESBL definitions have been proposed. First, the classical definition includes variants derived from TEM‐1, TEM‐2, or SHV‐1; K1 (KOXY) of Klebsiella oxytoca. Second, the broadened definition has stretched the classical definition of ESBL to include: (1) β‐lactamases (CTX‐M‐ESBLs, GES‐ESBLs, and VEB‐ESBLs), with spectra similar to those of TEM and SHV variants (designated as TEM‐ and SHV‐ESBLs, respectively) but derived from other sources; (2) TEM and SHV variants with borderline ESBL activity; e.g., TEM‐12; and (3) various β‐lactamases conferring wider resistance than their parent types but not meeting the definition for group 2be; e.g., OXA‐types (OXA‐ESBLs) and mutant AmpC‐types (AmpC‐ESBLs), with increased activity against oxyimino‐cephalosporins and with resistance to clavulanic acid. Third, the all‐inclusive definition includes: (1) ESBLA (named for class A ESBLs); (2) ESBLM (miscellaneous ESBLs), which has been subdivided into ESBLM‐C (class C; plasmid‐mediated AmpC) and ESBLM‐D (class D); and (3) ESBLCARBA (ESBLs with hydrolytic activity against carbapenems), which has been subdivided into ESBLCARBA‐A (class A carbapenemases), ESBLCARBA‐B (class B carbapenemases), and ESBLCARBA‐D (class D carbapenemases). The consensus view about the ESBL definition is that the classical ESBL definition must be expanded to class A non‐TEM‐ and non‐SHV‐ESBLs (CTX‐M‐, GES‐, VEB‐ESBLs, etc.). However, these three definitions evoke rational debate on the question “Which would be included in the category of ESBLs among AmpC‐ESBLs, OXA‐ESBLs, and/or carbapenemases?” Therefore, there is a great need for consensus in the precise definition of ESBL.  © 2010 Wiley Periodicals, Inc. Med Res Rev 32:216‐232, 2012
Potential of carbohydrate‐binding agents as therapeutics against enveloped viruses
Authors: François K. O. , Balzarini J.
Published: June 2010

Twenty‐seven years after the discovery of HIV as the cause of AIDS more than 25 drugs directed against four different viral targets (i.e. reverse transcriptase, protease, integrase, envelope gp41) and one cellular target (i.e. CCR5 co‐receptor) are available for treatment. However, the search for an efficient vaccine is still ongoing. One of the main problems is the presence of a continuously evolving dense carbohydrate shield, consisting of N‐linked glycans that surrounds the virion and protects it against efficient recognition and persistent neutralization by the immune system. However, several lectins from the innate immune system specifically bind to these glycans in an attempt to process the virus antigens to provoke an immune response. Across a wide variety of different species in nature lectins can be found that can interact with the glycosylated envelope of HIV‐1 and can block the infection of susceptible cells by the virus. In this review, we will give an overview of the lectins from non‐mammalian origin that are endowed with antiviral properties and discuss the complex interactions between lectins of the innate immune system and HIV‐1. Also, attention will be given to different carbohydrate‐related modalities that can be exploited for antiviral chemotherapy.  © 2010 Wiley Periodicals, Inc. Med Res Rev
5‐fluorouracil metabolite patterns in viable and necrotic tumor areas of murine colon carcinoma determined by 19F NMR spectroscopy
Authors: Kamm Yvonne J. L. , Heerschap Arend , Rosenbusch Gert , Rietjens Ivonne M. C. M. , Vervoort Jacques , Wagener D. J. Theo
Published: June 2010

High‐resolution 19F NMR spectroscopy at 9.4 T was used to study the difference in the metabolite pattern of 5‐fluorouracil (5‐FU) between viable and necrotic tissues of C38 murine colon tumors grown in C57BI/6 mice. Studies were performed on perchloric acid extracts of these tumor fractions after 5‐FU treatment. The 19F nuclear magnetic resonance spectra exhibited resonances representing 5‐FU, the catabolites α‐fluoro‐β‐ureidopropionic acid and α‐fluoro‐β‐alanine, as well as several fluoronucleotide anabolites. The absolute concentrations of anabolites and catabolites and the anabolite‐to‐catabolite ratio were significantly lower in the necrotic fraction than in the viable tumor fraction 50 min after administration of 5‐FU, whereas the absolute concentration of 5‐FU was the same. Therefore, in 5‐FU metabolism studies with NMR spectroscopy, it is important to consider the necrotic contribution to the tumor volume.
Intracellular bimodal nanoparticles based on quantum dots for high‐field MRI at 21.1 T
Authors: Rosenberg Jens T. , Kogot Joshua M. , Lovingood Derek D. , Strouse Geoffrey F. , Grant Samuel C.
Published: June 2010

Multimodal, biocompatible contrast agents for high magnetic field applications represent a new class of nanomaterials with significant potential for tracking of fluorescence and MR in vitro and vivo. Optimized for high‐field MR applications—including biomedical imaging at 21.1 T, the highest magnetic field available for MRI—these nanoparticles capitalize on the improved performance of chelated Dy3+ with increasing magnetic field coupled to a noncytotoxic Indium Phosphide/Zinc Sulfide (InP/ZnS) quantum dot that provides fluorescence detection, MR responsiveness, and payload delivery. By surface modifying the quantum dot with a cell‐penetrating peptide sequence coupled to an MR contrast agent, the bimodal nanomaterial functions as a self‐transfecting high‐field MR/optical contrast agent for nonspecific intracellular labeling. Fluorescent images confirm sequestration in perinuclear vesicles of labeled cells, with no apparent cytotoxicity. These techniques can be extended to impart cell selectivity or act as a delivery vehicle for genetic or pharmaceutical interventions. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
The history of the second‐trimester sonographic markers for detecting fetal Down syndrome, and their current role in obstetric practice
Authors: Benacerraf Beryl R.
Published: June 2010

This review summarizes the development, history and use of second‐trimester sonographic markers for the detection of fetal Down syndrome over three decades. Starting with the nuchal fold thickening in 1985 and culminating in the genetic sonogram in the 1990s. The combination of second‐trimester serum screening with the ultrasound markers improved the detection rate of affected fetuses but also allowed patients to decrease their risk of carrying a fetus with Down syndrome if the genetic sonogram was normal. More recently the role of the genetic sonogram and its markers have changed with the wide spread use of first‐trimester screening. This prior screening ultimately decreases the prevalence of fetal Down syndrome in the second trimester to less than 85% of what it was in the first‐trimester as most fetuses with Down syndrome are now identified early. Current interpretation of the second‐trimester Down syndrome markers must be based on the result of the first trimester and combined screening to achieve the most accurate risk estimate of an affected fetus. Copyright © 2010 John Wiley & Sons, Ltd.
Fetal cardiac scanning today
Authors: Allan Lindsey
Published: June 2010

The ability to examine the structure of the fetal heart in real‐time started over 30 years ago now. The field has seen very great advances since then, both in terms of technical improvements in ultrasound equipment and in dissemination of operator skills. A great deal has been learnt about normal cardiac function in the human fetus throughout gestation and how it is affected by pathologies of pregnancy. There is increasing recognition of abnormal heart structure during routine obstetric scanning, allowing referral for specialist diagnosis and counselling. It is now possible to make accurate diagnosis of cardiac malformations as early as 12 weeks of gestation. Early diagnosis of a major cardiac malformation in the fetus can provide the parents with a comprehensive prognosis, enabling them to make the most informed choice about the management of the pregnancy. Copyright © 2010 John Wiley & Sons, Ltd.
The 18‐week fetal examination and detection of anomalies
Authors: Eik‐Nes Sturla H.
Published: June 2010

From its beginning in the fifties the use of ultrasound in gynaecology and obstetrics has expanded extensively. Ultrasound technology has taken us from a time when the mother was our prime focus to the present where it is the unborn baby. Ultrasound assessments may have significant consequences for pregnancy care by optimizing the time, the mode and the location of the delivery as well as preparing the postnatal staff for a prenatally defined fetal problem. A major factor in the development was the groundbreaking work of an obstetrician, Ian Donald, and an engineer, Tom Brown, at Queen Mother's Hospital in Glasgow, who produced an ultrasound instrument called the Diasonograph. The first screening program offering a systematic ultrasound examination to a large pregnant population began in Malmoe, in 1973 and aimed to detect twins. Since then the examination has evolved over the years to include a systematic evaluation of the intrauterine contents. A number of randomized controlled trials have been reported and several large studies have reported the efficiency of routine fetal examinations for the detection of anomalies. Detection rates for the various subsets are presented. The learning curve regarding the ability to detect anomalies and the importance of proper training has also been shown. The procedure ‘routine fetal examination’ has been significant in supporting the continuous development of fetal medicine. The consequences of the improved dating of every pregnancy and the in utero transport of a sick fetus rather than an emergency transportation of a sick neonate, have an established evidence base. Ultrasound technology has had a remarkable ability to trigger great technical minds to move the technology forward year after year. Through a continuous cooperation between technicians and clinicians, this impressive technology of ultrasound will continue to support our work for the unborn child. Copyright © 2010 John Wiley & Sons, Ltd.
Efficient extraction of nucleolar proteins for interactome analyses
Authors: Chamousset Delphine , Mamane Sarah , Boisvert François‐Michel , Trinkle‐Mulcahy Laura
Published: June 2010

The efficient extraction of proteins from purified cellular organelles is critical for in vitro analyses, including identification of protein complex members by affinity purification‐based quantitative proteomic approaches. When applied to purified nucleoli, classic nuclear protein extraction methods inefficiently and selectively release only ∼50% of proteins. Here, we present a method that can extract up to 90% of nucleolar proteins, and apply it in a quantitative interactomic approach to identify nucleolar interaction partners for a mammalian protein phosphatase.
Proton and proton‐coupled electron transfer with paradigms towards single‐molecule systems
Authors: Kuznetsov A.M. , Ulstrup J.
Published: June 2010

Proton (PT), H‐atom and proton coupled electron transfer (PCET) are ubiquitously encountered in chemical and biological processes. PT and H‐atom transfer can belong to the partially or totally adiabatic limits representing ‘weak’ or ‘strong’ interactions between the donor and acceptor, reflected most conspicuously in large, i.e. ≫1 and small, i.e. 1–2, kinetic deuterium isotope effects (KIE). In view of the short proton/H‐atom transfer distances, the electronically adiabatic limit prevails in either case. The PCET notion applies from sequential PT and ET events to fully synchronous ET/PT as in H‐atom transfer. We first overview these notions. We then address several classes of PT reactions not commonly addressed in analytical condensed matter PT/H‐atom transfer theory. These include viscosity (relaxation) controlled PT and KIE < 1 in protein systems. Other classes are PT in strongly hydrogen bonded systems such as excess proton conduction in aqueous solution or in biological or synthetic membranes, and PT in the ‘inverted’ free energy region where excited proton vibrational states and a maximum in the Brønsted relation are important. We finally invoke an approach to single‐molecule PT and H‐atom transfer where the PT/H‐atom transferring molecules are enclosed between the substrate and tip in electrochemical (in situ) scanning tunnelling microscopy (STM) or between a pair of nanoscale electrodes. No data are presently available but could be within reach considering the recent success of in situ STM in single‐molecule electron transfer. Elusive notions such as PT/H‐atom transfer distances and distance dependent KIEs would become accessible based on this approach. Copyright © 2010 John Wiley & Sons, Ltd.
Particle size distribution in dilute liquid/liquid dispersions by light scattering
Authors: Lindsey E. E. , Chappelear D. C. , Sullivan D. M. , Augstkalns V. A.
Published: June 2010

Equal energy per unit mass (or volume) proved to be a valid scaling criterion for particle size distribution as well as mean particle size for geometrically similar vessels with a volume range of 4 to 1.

Binodal particle size distributions were observed. Although the coarse fraction varied as the −6/5 power of the agitation rate, the tine size was relatively independent of agitation rate.

The system with the greater drop viscosity gave a smaller fine‐fraction and a larger coarse‐fraction than the other system (IB/W).

Both systems approached equilibrium size slowly (many minutes). Equilibrium was approached more rapidly at high agitation rates. Differences were small between different tank sizes at equal energy dissipation rates per unit mass.

The average size of the fine fraction remains about the same through the run (although the amount increases). The size of the coarse fraction decreases with time. More experiments are necessary to elucidate the mechanism behind this.
Studies of the thermal behavior of polymers by torsional braid analysis
Authors: Gillham John K. , Lewis Armand F.
Published: June 2010

The application of the torsional braid technique to the thermal analysis of polymers (and monomers) is demonstrated. Included in this work are details of a visual method for estimating the dynamic mechanical damping factor of a freely oscillating system. Studies of a thermoplastic polymer and a thermosettiiig resin are presented in which their thermal behavior is demonstrated with respect to first and second order transitions, cure, thermal crosslinking and degradation. Isotactic polypropylene is studied as an example of a semi crystalline thermoplastic polymer. The monomer 1,3,5‐tria. crylylhexahydro‐8‐triazine represents an example of a thermosetting material. The dynamic mechanical data are compared with the results obtained by differential thermal analysis, thermo‐gravimetric analysis, and infrared spectroscopy.
Estimation of Z‐average molecular weight by light scattering in good solvents
Authors: Badley Jack H.
Published: June 2010

The unimodal molecular weight distributions found in many synthetic polymers can be fairly well characterized by the measurement of three different average molecular weights: the number‐, weight‐, and Z‐averages. The first two are easily measured; rhe third is more difficult to determine. This paper describes a light‐scattering method for the estimation of the Z‐average molecular weight which is applicable to random coil polymers in the molecular weight range between 0.2 × 106 and 2 × 106 and for which a suitable solvent is available. The solvent may be either a theta solvent or a good solvent for which the relation between intrinsic viscosity and molecular weight is known. The method depends on the fact, that, when angular dissymmetry of scattered light is observed, the Z‐average mean‐square radius of gyration of the polymer molecules, r2 can be determined. In a thela solvent, r2 is proportional to M, so that measurement of rz2 is equivalent to the determination of M̄z. In good solvents, r2 = kMb, and the corresponding molecular weight, called M̄d, is slightly different. The parameters k and b are derived from the relation between intrinsic viscosity and molecular weight in the test solvent. Provided that the dispersion of molecular weight is not too great, M̄d does not differ widely from M̄z, as b cannot exceed 1.2 for random coil molecules. Experimental tests in toluene on narrow molecular weight fractions of poly‐a‐methyl‐styrene and binary combinations of them gave results in accord with theory.
Diffusion in amorphous polymers
Authors: Paul D. R. , DiBenedetto A. T.
Published: June 2010

Diffusion and solubility coefficients are presented for He, Ne, Ar, and N2 in three ethylene‐propylene copolymers, two styrene‐butadiene copolymerg and a cis‐poly‐butadiene for five temperature levels in the range 0–50°C. The data were obtained by using a slightly modified Dow Gas Transmission Cell and analyzed by a new modified time‐lag technique which properly accounts for the increase in pressure on the downstream side of the cell. Activation energies were calculated for the twenty‐four diffusion systems and correlated with the polymer intermolecular forces and the gas molecule sizes by using ii cell theory for amorphous polymers which employs a potential energy depth parameter, ϵ*, a range parameter, p*, the number of degrees of freedom per structural unit (center), 3Cm, and the number of centers per unit cell, n. The first three parameters were evaluated from thermodynamic data, while n was evaluated from the diffusion data. It is believed that n is an indication of the number of backbone carbon atoms active in polymer segmental motion. The values obtained here (5–9) agree well with existing values estimated from polymer viscous flow data. A correlation for the solubility data is shown and a linear free energy relationship is discussed.
Gamma‐Radiation‐Induced Polymerization of Ethylene
Authors: Kukacka L. E. , Colombo P. , Steinberg M.
Published: June 2010

The kineties and product characteristics of the Co60 gamma‐radiation‐induced polymerization of ethylene have been studied as a function of pressure, radiation intensity, and temperature. Experiments were carried out under conditions which ranged in pressure from 170 to 1360 atm., in temperature from 20° to 200°C., and in radiation intensity from 5.8 × 1014 to 8.5 × 105 rad./hr. Activation energies of 0.2 and 14.5 kcal./mole were determined for the temperature ranges 20° to 100°C and 120° to 200°C., respectively. Empirical relationships for the rate of polymerization and the radiation yield for the range of pressure and radiation intensity studied and for temperatures between 20 and 100°C., are as follows: Q = (1.39 ± 0.37) × 10−8e−200/RT p2.7I0.5; G = (3.50 ± 0.95)e−200RTp2.5I−0.5, where Q = polymerization rate, g./l.‐hr., G = radiation yield, molecules/100 e.v., P = pressure, atm., and I = radiation intensity, rad./hr. The 0.5 power dependence of the intensity on rate indicates a free radical mechanism. The polymers produced over the entire range of conditions were found to be completely soluble. Densities ranged from 0.95 g./cc. for material formed at 20°C. to 0.91 g./cc. for material formed at 120°C. The weight average molecular weight decreased from 1.5 × 1016 to 4.7 × 104 over the same temperature range. The molecular weight was found to increase with pressure and with decreasing radiation intensity. All polymers formed at temperatures below 120°C. had a melt index of < 0.06 g./10 min.
Thermodynamic and molecular properties of amorphous high polymers
Authors: Paul D. R. , Dibenedetto A. T.
Published: June 2010

A potential energy function and an equation of state for amorphous polymers are developed by using a mathematical, quasi‐lattice model to represent the molecular structure. The potential energy function, obtained by dividing a polymer chain into a linked series of interaction centers, is described by three molecular parameters: e*, a force constant which measures the strength of interaction between two polymer segments, p*, a range parameter which measures the minimum separation between point centers on adjacent segments, and l, a structural parameter which indicates the size of the molecular units. A theoretical equation of state is then developed by defining a cell partition function for a polymer segment in terms of the potential energy function and one additional parameter, 3Cm, which is a measure of the number of external degrees of freedom possessed by an interaction center. It is shown that the theoretical equation for the thermal expansion at constant pressure simplifies to:

Similar expressions are developed for compressibility, internal pressure, and cohesive energy density. Experimental data for 13 polymers are then correlated using the theoretical equations. Densities, thermal expansion coefficients, and internal pressure measurements are used to evaluate the molecular parameters. Internal pressures over a range of temperatures are correlated to within 1% (in the best case). The cohesive energy density and the glass transition temperature are also interpreted in terms of the model. The molecular force parameters are also evaluated by a modified Slater‐Kirkwood calculation, and the results are compared to the experimentally determined values. A physical interpretation is then discussed in light of these calculations. The tentative conclusions are that the thermodynamic properties of amorphous polymers can be correlated with a model containing four molecular parameters. Two of these parameters, e* and p*, are associated with the nature of the interaction potential between structural units along the chain and can perhaps be estimated theoretically. The parameter l, a measure of the size of a structural unit on a polymer chain, has a strong effect on the repulsion between polymer segments and must be evaluated from experimental data. The parameter 3Cm is a measure of the mobility and freedom of a polymer chain and must be evaluated from experimental data. The change of a given polymer from a rubbery to a glassy state probably can be related to large changes in this latter parameter.
Étude par Spectrographie Infra‐rouge de Quelques Modifications de la Structure des Fibres de Polyamides Provoquées par les Traitements d'Ennoblissement (Fixage Thermique, Texturation)
Authors: Bouriot P. , Parisot A.
Published: June 2010

Structural changes induced in nylon 66 fibers by heat‐treatment during industrial texturizing processes (at 165 and 200°C.), whether or not followed by steam‐setting at 130°C., have been investigated by means of infrared spectroscopy. Variations observed in the optical density of crystalline (935 cm.−1) and amorphous (1140 cm.−1) bands show a general increase in crystallinity of the polyamide, owing to heat treatment, chiefly in the water vapor phase. The crystallizing effect of steam‐setting seems all the stronger as the initial crystallinity of the specimen is smaller. In the case of dry‐heat treatments, crystallinity rises in the order of increasing temperatures. Likewise, heavy‐water accessibility diminishes also, owing to heat‐treatment, and chiefly in the water vapor phase. The examination by polarized light of NH and ND groups in fibers treated with heavy water shows a decrease in the degree of orientation of inaccessible and accessible areas under the influence of heat. This denotes some disorientation of the structure as a whole. No significant changes can be observed in the mean energy of hydrogen interactions, however. A general interpretation of the phenomena observed is suggested.
A kinetic study of ziegler‐natta propylene polymerization
Authors: Keii T. , Soga K. , Saiki N.
Published: June 2010

The kinetics of the propylene polymerization with TiCl3‐AlEt3 has been investigated in the temperature range (30‐70°C.), the pressure range of propylene (100‐700 mm. Hg), and the concentration range of the catalysts (2 g. TiCl3/liter, [A]/[Ti] = 0.4‐3.0). The polymerization rate R increases rapidly with the polymerization time t at first (stage I), which is followed by a gradual decrease to the stationary value Roo, (stage II). The kinetic behavior in stage I in the case when propylene is introduced after the addition of AlEt3 is expressed by

and that in the case when propylene is introduced before the addition of AlEt3 is expressed by

The kinetic behavior in stage II, which is independent of the above procedure, is expressed by

where R∞ is the stationary rate represented by

and Ro a constant. The activation energies are E1 = 15, E2 = 17, Et3 = 2‐3, E3″ = 12, and EP = 10 kcal./mole, respectively. The heat of adsorption of AlEt3 was obtained as 12 kcal./ mole from the temperature dependence of K. Stage I is explained on the basis of the formation of polymerization centers from Al2Et6 and a propylene monomer on the surface of TiCl3. Stage II is attributed to an irreversible deactivation of the polymerization centers localized on unstable surface sites due mainly to a spontaneous process and partially to a propylene monomer (or polymer) attack.
The morphology of fibers from deformed polymer crystals
Authors: Ingram P. , Kiho H. , Peterlin A.
Published: June 2010

Electron diffraction and microscopy have been used to investigate the fine structure of fibrils pulled from deformed polyethylene and polyoxymethylene crystals. Since on annealing close to the melting point the striations developed transverse to the fibril axis are thought to be folded chain lamellae, we looked for evidence whereby folds could be detected prior to annealing. In addition to striations observed by allowing iodine vapors to diffuse into polyethylene fibrils, and by dark‐field observation, both reported earlier, we found (1) similar striations in polyoxymethylene by exposure to phosphotungstic acid, and (2) the presence of some monoclinic phase remaining in polyethylene from initial stages of deformation of orthorhombic folded chain crystals. It is suggested that blocks less than 200 A. long of the original crystals break off during deformation. On annealing, tie molecules and some unfolded chains relax and are incorporated into the blocks. The striation periodicity increases with annealing temperature and decreases with molecular weight. Little annealing time dependence is found. The periodicity was independent of draw temperature between 40 and 160°C. in polyoxymethylene indicating that folded chain lamellae could not be formed during deformation.
A study of the interaction of Ni(II) and Cu(II) with poly(acrylic acid)
Authors: McLaren J. V. , Watts J. D. , Gilbert A.
Published: June 2010

Potentiometric titrations have been carried out on a sample of poly(acrylic acid) of very high molecular weight (Mw = 1.92 × 106). At polymer concentrations greater than about 1 × 10−4 equiv./liter, this material behaves as a weaker acid, under given conditions, than when it is heat degraded, and also compared with a lower molecular weight sample of poly(acrylic acid) (Mw = 3.52 × 105). Only at very high dilutions are there indications that the three materials have the same pKa values. The titration curves reveal a conformational transition in poly (acrylic acid) in the range of α's of 0.2–0.5. Formation curves for the complexes between the high molecular weight poly‐(acrylic acid) and Cu2+ and Ni2+ have been calculated from the titration curves. At a polymer concentration of 2.4 × 10−3 equiv./liter, these metals form complexes in which two carboxylate groups are involved, whereas at a polymer concentration of 1.5 × 10−4 equiv./liter, the formation curves suggest the existence of complexes involving more than two carboxylate groups. This is thought to be due to enhanced intermolecular interaction which results in a reversible physically crosslinked system.