bluuebunny/crossref_metadata_2025 huggingface dataset:
Neurophysiologic and Rehabilitation Insights From the Split-Belt and Other Locomotor Adaptation Paradigms
Authors: Reisman Darcy S. , Bastian Amy J. , Morton Susanne M.
Published: December 2009

Locomotion is incredibly flexible. Humans are able to stay upright and navigate long distances in the face of ever-changing environments and varied task demands, such as walking while carrying a heavy object or in thick mud. The focus of this review is a behavior that is critical for this flexibility: motor adaptation. Adaptation is defined here as the process of adjusting a movement to new demands through trial-and-error practice. A key feature of adaptation is that more practice without the new demand is required to return the movement to its original state. Thus, motor adaptation is a short-term motor learning process. Several studies have been undertaken to determine how humans adapt walking to novel circumstances. Many of these studies have examined locomotor adaptation using a split-belt treadmill. The results of these studies of people who were healthy and people with neurologic damage suggest that the cerebellum is required for normal adaptation of walking and that the role of cerebral structures may be less critical. They also suggest that intersegmental and interlimb coordination is critical but readily adaptable to accommodate changes in the environment. Locomotor adaptation also can be used to determine the walking potential of people with specific neurologic deficits. For instance, split-belt and limb-weighting locomotor adaptation studies show that adults with chronic stroke are capable of improving weight-bearing and spatiotemporal symmetry, at least temporarily. Our challenge as rehabilitation specialists is to intervene in ways that maximize this capacity.
Meaningful Gait Speed Improvement During the First 60 Days Poststroke: Minimal Clinically Important Difference
Authors: Tilson Julie K. , Sullivan Katherine J. , Cen Steven Y. , Rose Dorian K. , Koradia Cherisha H. , Azen Stanley P. , Duncan Pamela W. ,   for the Locomotor Experience Applied Post Stroke (LEAPS) Investigative Team
Published: December 2009

Background

When people with stroke recover gait speed, they report improved function and reduced disability. However, the minimal amount of change in gait speed that is clinically meaningful and associated with an important difference in function for people poststroke has not been determined.

Objective

The purpose of this study was to determine the minimal clinically important difference (MCID) for comfortable gait speed (CGS) associated with an improvement in the modified Rankin Scale (mRS) score for people between 20 to 60 days poststroke.

Design

This was a prospective, longitudinal, cohort study.

Methods

The participants in this study were 283 people with first-time stroke prospectively enrolled in the ongoing Locomotor Experience Applied Post Stroke (LEAPS) multi-site randomized clinical trial. Comfortable gait speed was measured and mRS scores were obtained at 20 and 60 days poststroke. Improvement of ≥1 on the mRS was used to detect meaningful change in disability level.

Results

Mean (SD) CGS was 0.18 (0.16) m/s at 20 days and 0.39 (0.22) m/s at 60 days poststroke. Among all participants, 47.3% experienced an improvement in disability level ≥1. The MCID was estimated as an improvement in CGS of 0.16 m/s anchored to the mRS.

Limitations

Because the mRS is not a gait-specific measure of disability, the estimated MCID for CGS was only 73.9% sensitive and 57.0% specific for detecting improvement in mRS scores.

Conclusions

We estimate that the MCID for gait speed among patients with subacute stroke and severe gait speed impairments is 0.16 m/s. Patients with subacute stroke who increase gait speed ≥0.16 m/s are more likely to experience a meaningful improvement in disability level than those who do not. Clinicians can use this reference value to develop goals and interpret progress in patients with subacute stroke.
Striding Out With Parkinson Disease: Evidence-Based Physical Therapy for Gait Disorders
Authors: Morris Meg E. , Martin Clarissa L. , Schenkman Margaret L.
Published: December 2009

Although Parkinson disease (PD) is common throughout the world, the evidence for physical therapy interventions that enable long-term improvement in walking is still emerging. This article critiques the major physical therapy approaches related to gait rehabilitation in people with PD: compensatory strategies, motor skill learning, management of secondary sequelae, and education to optimize physical activity and reduce falls. The emphasis of this review is on gait specifically, although balance and falls are of direct importance to gait and are addressed in that context. Although the researchers who have provided the evidence for these approaches grounded their studies on different theoretical paradigms, each approach is argued to have a valid place in the comprehensive management of PD generally and of gait in particular. The optimal mix of interventions for each individual varies according to the stage of disease progression and the patient's preferred form of exercise, capacity for learning, and age.
Rectus Femoris to Gracilis Muscle Transfer With Fractional Lengthening of the Vastus Muscles: A Treatment for Adults With Stiff Knee Gait
Authors: Namdari Surena , Pill Stephan G. , Makani Amun , Keenan Mary Ann
Published: December 2009

Background

Stiff knee gait, which may be seen in patients with upper motor neuron injury, describes a gait pattern with a relative loss of sagittal knee motion. It interferes with foot clearance during swing, often leading to inefficient compensatory mechanisms and ambulatory dysfunction. Distal rectus femoris muscle transfers and fractional lengthening of the vastus muscles have been performed in adult patients.

Objective

The purpose of this study was to describe a unique surgical technique and report on initial outcomes.

Design

A retrospective case-series study design was used.

Methods

The patients were adults with stiff knee gait due to stroke or traumatic brain injury who underwent distal rectus femoris muscle transfer with fractional lengthening of the vastus muscles. The patients (19 men and 18 women) had an average age of 51 years at the time of surgery. Lower-extremity examinations, clinical gait analyses, and satisfaction levels were recorded preoperatively and postoperatively.

Results

At a mean follow-up time of 10 months, 36 (97%) of the 37 patients were satisfied with their clinical and functional results, and the average Viosca score improved from 3.1 to 3.5.

Limitations

Limitations of the study include use of a retrospective design, lack of a control group, and limited quantitative measures of gait.

Conclusion

Distal rectus femoris muscle transfer and fractional lengthening of the vastus muscles were found to be a possible treatment for adults with stiff-knee gait caused by stroke or traumatic brain injury.
Can Interdistrict Choice Boost Student Achievement? The Case of Connecticut’s Interdistrict Magnet School Program
Authors: Bifulco Robert , Cobb Casey D. , Bell Courtney
Published: December 2009

Connecticut’s interdistrict magnet schools offer a model of choice-based desegregation that appears to satisfy current legal constraints. This study presents evidence that interdistrict magnet schools have provided students from Connecticut’s central cities access to less racially and economically isolated educational environments and estimates the impact of attending a magnet school on student achievement. To address potential selection biases, the analyses exploit the random assignment that results from lottery-based admissions for a small set of schools, as well as value-added and fixed-effect estimators that rely on pre–magnet school measures of student achievement to obtain effect estimates for a broader set of interdistrict magnet schools. Results indicate that attendance at an interdistrict magnet high school has positive effects on the math and reading achievement of central city students and that interdistrict magnet middle schools have positive effects on reading achievement.
Maternal serum placental growth factor and soluble fms‐like tyrosine kinase 1 as early predictors of preeclampsia
Authors: SHOKRY MAHMOUD , BEDAIWY MOHAMED A. , FATHALLA MOHAMED M.F. , ALSEMARY ALI , ELWAKIL SAHAR , MURPHY AISLING
Published: December 2009

The aim of this study was to identify pregnant women at risk of preeclampsia (PE) before clinical manifestations appeared using a panel of serum markers. We recruited 240 consecutive women who presented for antenatal care. We investigated whether serum levels of placental growth factor (PlGF), its inhibitor, soluble fms‐like tyrosine kinase‐1 (sFlt‐1), measured at 13–16 weeks gestation and the expression of fms‐like tyrosine kinase‐1 (Flt‐1) in the maternal neutrophils measured by flow cytometry could be predictive of the subsequent development of PE. Serum PlGF levels were found to be significantly lower among women who developed PE than patients with gestational hypertension or patients in the control group (p < 0.001). In contrast, serum sFlt1 levels were most elevated in patients who developed PE versus those with gestational hypertension or the control group (p < 0.001). Serum levels of neutrophil‐Flt‐1, however, were lower in women who developed PE than in those with gestational hypertension or those in the control group (p < 0.001). Increased serum levels of sFlt‐1, decreased levels of neutrophil‐Flt‐1, and decreased levels of PlGF may predict women at risk of developing PE later in pregnancy.
Fibrinogen and histidine‐rich glycoprotein in early‐onset preeclampsia
Authors: KÅREHED KARIN , WIKSTRÖM ANNA‐KARIN , OLSSON ANNA‐KARIN , LARSSON ANDERS , OLOVSSON MATTS , ÅKERUD HELENA
Published: December 2009

Objective. To determine whether plasma levels of fibrinogen and the placental tissue distributions of fibrinogen and histidine‐rich glycoprotein (HRG) differ between early‐ and late‐onset preeclampsia. Design. The study comprised 18 women with early‐onset (gestational weeks 24–32) and 19 women with late‐onset (gestational weeks 35–42) preeclampsia. As controls concerning the plasma levels of fibrinogen, we used samples from non‐pregnant fertile women, healthy pregnant women at gestational weeks 24–32 and healthy pregnant women at gestational weeks 35–42. Placental samples from women with healthy pregnancies at gestational weeks 35–42 served as controls in the immunohistochemical staining. Setting. Uppsala University Hospital, Uppsala. Methods. Plasma fibrinogen levels were analyzed and the placental tissue expression of fibrinogen and HRG determined by immunohistochemistry. Results. Plasma level of fibrinogen was increased in early‐onset, but not late‐onset, preeclampsia. Levels of fibrinogen were significantly lower, and that of HRG significantly higher, in placentas from women with early‐onset preeclampsia as compared with control placentas (p = 0.01 and 0.001). Conclusions. HRG and fibrinogen might be involved in the hypercoagulability and the angiogenic imbalance seen in early‐onset preeclampsia.
Mid‐pregnancy androgen levels are negatively associated with breastfeeding
Authors: CARLSEN SVEN MAGNUS , JACOBSEN GEIR , VANKY ESZTER
Published: December 2009

Objective. Breastfeeding depends on endocrine changes during pregnancy. The association between gestational hormones and lactation has been sparsely investigated. Previously, androgens were used for lactation inhibition. We investigated a possible association between second trimester maternal androgen levels and breastfeeding. Design. Prospective observational study.

Setting. University hospital setting. Population. Women from a random sample of pregnancies (n = 63) and from a group with an increased risk for giving birth to a small‐for‐gestational age newborn (n = 118) were included. All participants had singleton pregnancies and one or two previous births. Methods. Maternal androgen levels were measured in gestational week 25. The association with reported breastfeeding was explored by univariate and multivariate linear regression analyses. Analyses were adjusted for factors known to be associated with breastfeeding. Main outcome measures. Breastfeeding at six weeks, three months, and six months postpartum. Results. In the random group, breastfeeding at three and six months was negatively associated with maternal testosterone, androstendione, and free testosterone index levels. After correction for maternal age, education and smoking, breastfeeding at both three and six months was negatively associated with the free testosterone index. In the group of women with an increased risk for giving birth to a small‐for‐gestational age newborn, breastfeeding at six weeks and three months was associated negatively with maternal dehydroepiandrosterone and this association persisted after correction for maternal age, education, and smoking. Conclusions. Maternal androgen levels in mid‐pregnancy are negatively associated with breastfeeding.
Two naturally occurring variants of the serotonin receptor geneHTR3Care associated with nausea in pregnancy
Authors: GOECKE TAMME W. , EKICI ARIF B. , NIESLER BEATE , LOEHBERG CHRISTIAN R. , HAMMER CHRISTIAN , RAPPOLD GUDRUN , SCHANZE DENNY , STRAUB VERICA , ALTMANN HANS‐HARALD , STRISSEL PAMELA , STRICK REINER , BECKMANN MATTHIAS W. , FASCHING PETER A.
Published: December 2009

Objective.To assess the association between pregnancy‐associated symptoms and common single nucleotide polymorphisms (SNPs) in genes known to be involved in the pathogenesis of nausea and vomiting.Design.In a standardized, questionnaire‐based interview, women selected from a control cohort for association studies were asked retrospectively about nausea and vomiting during their first pregnancy.Population.A total of 593 women who had completed at least one pregnancy and for whom germline DNA was available were selected.Methods.Eight SNPs in the serotonin receptor genes HTR3A, HTR3B, HTR3C, HTR3D, HTR3E, and NK1R (TACR1) were tested using polymerase chain reaction. The occurrence of nausea and vomiting was correlated with the patients’ genotyping results and medical history parameters.Results.Both young age at first pregnancy and positive smoking status were significantly associated with vomiting and nausea during pregnancy. After adjustment for these two parameters, the two SNPs rs6806362 (odds ratio (OR) 1.38 per allele; 95% confidence interval (CI) 1.06–1.79;p= 0.017) and rs6807670 (OR 1.37; 95% CI 1.05–1.79 per allele;p= 0.023) were marginally associated with pregnancy‐related nausea. None of the other polymorphisms showed any association.Conclusion.Polymorphisms in the subunit gene HTR3C of the serotonin receptor may be involved in the pathogenesis of pregnancy‐associated nausea.
Body mass index as a prognostic factor in epithelial ovarian cancer and correlation with clinico‐pathological factors
Authors: SKÍRNISDÓTTIR INGIRIDUR , SORBE BENGT
Published: December 2009

Objective. To find out if body mass index (BMI) was associated with clinico‐pathological features and prognosis in epithelial ovarian cancer (EOC). Design. Retrospective cohort study. Setting. Patients with EOC, who underwent primary surgery and postoperative chemotherapy in the Örebro Medical Region, Sweden, 1994–2003. Sample. A total of 446 patients with stage I–IV EOC, who underwent primary surgery and chemotherapy with information of values of height and weight at the start of chemotherapy were eligible. Methods. Patients were stratified by BMI according to guidelines set forth by the World Health Organization. Pearson's chi‐squared test was used for univariate analyses. The level of statistical significance was p < 0.05. Main outcome measures. The survival curves were generated by using the Kaplan‐Meier method, and in multivariate analyses the Cox regression model was used with cancer‐specific survival as the end point. Results. Of the patients, 5% were underweight (BMI < 18.5), 55% were of ideal body weight (BMI 18.5–25), 25% were overweight (BMI 25–30) and 15% were obese (BMI > 30). Among patients with serous tumors a significant (p = 0.01) worse survival was found in the subgroup of underweight (BMI < 18.5) patients compared with patients in the other BMI groups. In multivariate analysis only FIGO‐stage and age were independent and significant prognostic factors. Conclusion. Overweight and obese patients did not have worse survival than normal weight and underweight patients. The prognostic impact of BMI on survival was only noted for underweight patients with serous tumors.
COX‐2 expression in uterine carcinosarcoma
Authors: MENCZER JOSEPH , SCHREIBER LETIZIA , SUKMANOV OLEG , KRAVTSOV VLADIMIR , BERGER ESTHER , GOLAN ABRAHAM , LEVY TALLY
Published: December 2009

Objective. To assess cyclooxygenase‐2 (COX‐2) expression in the carcinomatous and sarcomatous elements of uterine carcinosarcoma. Design. Retrospective study. Setting. Medical center. Sample. Twenty‐seven consecutive uterine specimens with carcinosarcoma. Methods. COX‐2 expression assessment by immunohistochemistry was performed on deparaffinized sections of paraffin‐embedded tissue blocks. Analysis of all stained tissue sections was done by means of light microscopy counting 10 high power fields with a minimum of 1,000 cells per slide. Analysis of the stained tissue sections was done by pathologists blinded to the clinical data and the follow‐up course of the malignancy. Main outcome measures. Staining of more than 10% of the cells was considered positive. Staining intensity was graded on a 0–3 scale. A scoring index was calculated by multiplying the intensity grade by the percentage of stained cells and considered low when it was ≤1 and high when it was >1. COX‐2 expression was associated with prognostic factors and survival. Results. COX‐2 immunohistochemical staining was positive in 74% of the carcinomatous component of carcinosarcoma and a high staining score was observed in 48.2%. Staining parameters were significantly lower in the sarcomatous component. No significant association between COX‐2 expression with stage, grade, depth of myometrial invasion, lymphvascular involvement or with survival was observed. Conclusions. COX‐2 is expressed in a high percentage of uterine carcinosarcoma, but does not seem to be associated with prognostic factors or survival.
A randomized trial comparing changes in sexual health and psychological well‐being after subtotal and total hysterectomies
Authors: ELLSTRÖM ENGH MARIE A , JERHAMRE KARIN , JUNSKOG KARIN
Published: December 2009

Objective. To evaluate changes in sexual health and psychological well‐being one year after subtotal and total hysterectomies. Design. Prospective randomized controlled trial. Material and methods. One hundred and thirty‐two premenopausal patients scheduled for hysterectomy without planned oophorectomy for benign disorders and without a history of cervical dysplasia or symptomatic prolapse were randomized to total (n = 66) or subtotal hysterectomy (n = 66). The McCoy Female Sexuality Questionnaire was used to evaluate changes in sexual health and the Psychological General Well‐Being index was used to evaluate changes in psychological well‐being. Differences in outcome before and one year after the hysterectomy were calculated for each individual, and changes compared between the groups. Results. Women who had subtotal hysterectomy (SH) reported a significantly greater positive change in frequency of orgasm and sexual pleasure as compared with women who had total hysterectomy (TH) (mean values ± standard deviation (SD), orgasm: SH: 0.4 ± 1.1; TH: ‐0.2 ± 0.9, p = 0.012, sexual enjoyment: SH 0.3 ± 1.5; TH: ‐0.3 ± 1.3, p = 0.039). There was a significantly greater general health gain for the women who underwent subtotal hysterectomy as compared with total hysterectomy (mean values ± SD SH: 1.2 ± 2.3; TH: 0.3 ± 1.6, p = 0.03). The total score did not show a difference. Conclusions. Women undergoing subtotal hysterectomy experience a greater positive change in the frequency of orgasm and extent of sexual pleasure after surgery than women undergoing total hysterectomy, but the results must be interpreted with caution.
Occurrence of pharyngeal Chlamydia trachomatis is uncommon in patients with a suspected or confirmed genital infection
Authors: WIKSTRÖM ARNE , ROTZÉN‐ÖSTLUND MARIA , MARIONS LENA
Published: December 2009

Objective. To evaluate how common pharyngeal Chlamydia trachomatis (CT) is among mainly heterosexual women and men with a confirmed or a highly suspicious genital infection having had recent unprotected active oral sex. Design. Prospective observational study. Setting. Out‐patient clinics for sexually transmitted infections in Stockholm. Population. A total of 143 women and 138 men with a confirmed or suspected genital CT infection and a history of active oral sex. Methods. Pharyngeal samples from men and women in the study population were analyzed for the presence of CT. Main outcome measures. Number of positive CT in pharyngeal samples in relation to positive CT in genital samples. Results. Of the women, 9/128 (7.0%) were positive in the pharyngeal samples. None were exclusively positive in the pharynx. Three of 110 men (2.7%) had pharyngeal involvement. One man was positive in the pharynx as well as in the urine sample, and two men were exclusively pharyngeal CT positive. Conclusions. The finding of CT in the pharynx is not common in spite of the presence of a genital infection and a history of active oral sex.
Evaluation of gonadotropin‐releasing hormone agonist treatment for prevention of menstrual‐related attacks in acute porphyria
Authors: INNALA EVA , BÄCKSTRÖM TORBJÖRN , BIXO MARIE , ANDERSSON CHRISTER
Published: December 2009

Objective. To describe the benefits and adverse effects of gonadotropin‐releasing hormone (GnRH) agonist treatment for prevention of recurrent menstrual attacks in women with acute intermittent porphyria and variegate porphyria. To describe concomitant add‐back therapies with estradiol and progesterone and describe their benefits and adverse effects. Design. A retrospective follow‐up with questionnaires, interviews and medical records. Setting. Out‐patient care at the Umeå University Hospital in Sweden. Population. Sixteen Caucasian women with DNA‐diagnosed porphyria and menstrual‐cycle‐related porphyria attacks were treated with GnRH agonists during 1984–2000. Fourteen women participated. The mean age when treatment started was 33 years (17–48 years). The duration of treatment varied between 5 months and 9 years. Methods. GnRH agonists were administered by the intranasal route or by injections. To reduce menopausal symptoms, add‐back therapy with low doses of estradiol was administered, and for endometrial protection progesterone was usually administered. Main outcome measures. Treatment effects and adverse events as detected in questionnaires, interviews and medical records. Results. Eleven women reported benefits from GnRH agonist treatment with less intense and/or less frequent porphyria attacks, and in four of them attacks almost disappeared. Two women reported no change. One woman had only temporary improvement. Porphyria attacks were triggered by solely estradiol add‐back in two women and in five of nine women when progesterone was given. Conclusions. GnRH agonist treatment can ameliorate menstrual‐cycle‐related attacks of porphyria. Dose findings for GnRH agonists and add‐back regimes especially for progesterone are intricate.
Changed indications for cesarean sections
Authors: STJERNHOLM YLVA VLADIC , PETERSSON KARIN , ENEROTH EVA
Published: December 2009

Objective. The aim of this study was to investigate the indications for cesarean sections in the early 1990s as compared to the middle 2000s. Design. Retrospective cohort study. Methods. Data were collected from original obstetrical records in a tertiary hospital in 1992 and 2005. Results. The total cesarean delivery rate rose from 11% to 20%. The main indications for an elective cesarean in 1992 were a pathological fetal lie or a uterine factor. The dominant indication for an elective cesarean in 2005 was a psychosocial indication defined as maternal fear of childbirth or maternal request without any co‐existing medical indication. Presumed fetal compromise and prolonged labor remained the main indications for urgent and emergency cesareans. No apparent alterations in population characteristics could be identified for these years. Conclusions. The increased rate of elective cesareans for psychosocial indications would reflect altered attitudes towards mode of delivery in the childbearing population and among obstetricians. We suggest that extended support from community antenatal care should be provided and that standardized keys aiding a physician in decision‐making procedures concerning the cesarean section practice should be developed.
The complete chloroplast genome of tall fescue (Lolium arundinaceum; Poaceae) and comparison of whole plastomes from the family Poaceae
Authors: Cahoon A. Bruce , Sharpe Richard M. , Mysayphonh Chansamone , Thompson Elizabeth J. , Ward Andrea D. , Lin Anhua
Published: December 2009

In this paper, we describe the complete chloroplast genome of Lolium arundinaceum. This sequence is the culmination of a long‐term project completed by >400 undergraduates who took general genetics at Middle Tennessee State University from 2004–2007. It was undertaken in an attempt to introduce these students to an open‐ended experiential/exploratory lesson to produce and analyze novel data. The data they produced should provide the necessary information for both phylogenetic comparisons and plastome engineering of tall fescue. The fescue plastome (GenBank FJ466687) is 136048 bp with a typical quadripartite structure and a gene order similar to other grasses; 56% of the plastome is coding region comprised of 75 protein‐coding genes, 29 tRNAs, four rRNAs, and one hypothetical coding region (ycf). Comparisons of Poaceae plastomes reveal size differences between the PACC (subfamilies Panicoideae, Arundinoideae, Centothecoideae, and Chloridoideae) and BOP (subfamilies Bambusoideae, Oryzoideae, and Pooideae) clades. Alignment analysis suggests that several potentially conserved large deletions in previously identified intergenic length polymorphic regions are responsible for the majority of the size discrepancy. Phylogenetic analysis using whole plastome data suggests that fescue closely aligns with Lolium perenne. Some unique features as well as phylogenetic branch length calculations, however, suggest that a number of changes have occurred since these species diverged.
Genetic structure and breeding system of a rare understory herb, Dysosma versipellis (Berberidaceae), from temperate deciduous forests in China
Authors: Guan Bi‐Cai , Fu Cheng‐Xing , Qiu Ying‐Xiong , Zhou Shi‐Liang , Comes Hans Peter
Published: December 2009

To evaluate the role of Quaternary refugial isolation in allopatric (incipient) speciation of East Asian temperate forest biotas, we analyzed amplified fragment length polymorphisms (AFLPs) and the breeding system in Dysosma versipellis. The study revealed that D. versipellis is mostly self‐incompatible, genetically highly subdivided and depauperate at the population level (e.g., ΦST = 0.572/HE = 0.083), and characterized by a low pollen‐to‐seed migration ratio (r ≈ 4.0). The latter outcome likely reflects limited pollen flow in a low‐seed disperser whose hypothesized “sapromyophilous” flowers undergo scarce, inefficient, and likely specialized cross‐pollination by small Anoplodera beetles, rather than carrion flies as assumed previously. In consequence, fruit set in D. versipellis was strongly pollen‐limited. Our AFLP data support the hypothesis of a long‐standing cessation of gene flow between western and central eastern populations, consistent with previous chloroplast DNA data. This phylogeographic pattern supports the role of the Sichuan Basin as a floristic boundary separating the Sino‐Himalayan vs. Sino‐Japanese Forest subkingdoms. Our genetic data of D. versipellis also imply that temperate deciduous forest elements to the west and the east of this basin responded differently to Quaternary climate change, which may have triggered or is leading to allopatric (incipient) speciation.
Molecular systematics of the neotropical genus Psiguria (Cucurbitaceae): Implications for phylogeny and species identification
Authors: Steele P. Roxanne , Friar Lauren M. , Gilbert Lawrence E. , Jansen Robert K.
Published: December 2009

Varying morphological features in many groups of tropical vines confound identification, requiring molecular tools for distinguishing species. Confusion is amplified in Psiguria, a small genus found in Central and South America and the Caribbean, because male and female flowers of these monoecious plants are widely separated by time and position on a branch. We present the first phylogeny of Psiguria utilizing a combination of eight chloroplast intergenic spacers, the internal transcribed spacer (ITS) regions of the nuclear ribosomal DNA repeat, and the intron of the low‐copy nuclear gene serine/threonine phosphatase, for a total aligned length of 9456 base pairs. Analyses include multiple accessions of all species in the genus. The data support the monophyly of Psiguria and elucidate several species boundaries. Also presented are Psiguria‐specific DNA barcodes, which include the chloroplast regions: ndhC‐trnV, rps16‐trnQ, rpoB‐trnC, ndhF‐rpl32, and psbZ‐trnM. For the first time, systematists, ecologists, and evolutionary biologists will have the tools to confidently identify species of Psiguria with DNA barcodes that may be useful in other genera of Cucurbitaceae.
Espacios naturales en zonas urbanas. Análisis comparado de la ciudad alemana de Halle y las chilenas de San Pedro de la Paz y Talcahuano
Authors: Priego González de Canales Carlos , Breuste Jürgen H. , Rojas Hernández Jorge
Published: December 2009

Con el objetivo de estudiar la percepción social y la valoración de la naturaleza por personas de diferente estrato social y en ciudades de diferente cultura, se inició un proyecto de cooperación internacional entre Alemania y Chile. Para la realización de este proyecto comparativo se escogieron barrios de clase media-alta y media-baja en cada uno de los países. En Alemania se estudiaron los barrios de Silberhöhe y Paulusviertel de la ciudad de Halle, y en Chile el sector de Tumbes (Comuna de Talcahuano) y la Comuna de San Pedro de la Paz, VIII Región del Biobío. La herramienta base para el estudio fue la aplicación de una encuesta base con las mismas preguntas para cada uno de los países. Se determinó cómo las personas de diferentes procedencias sociales y culturales presentaban un diferente uso y percepción del paisaje urbano. De la misma manera, en Chile la condición social del ciudadano condiciona la posibilidad de acceso a áreas verdes y de recreo.
Adhesives
Authors: Pocius Alphonsus , Campbell Christopher J.
Published: December 2009

An adhesive is a material used to join two or more other materials (often called adherends) by means of surface attachment to form a final assembly. In the simplest case, the assembly is called an adhesive joint or adhesive bond. Adhesives can be made from any material that displays the properties required for an adhesive. These properties include: adhesion (the ability to “surface attach”), the handling characteristics of the adhesive (so that it can be easily and economically applied to the adherends), the curing characteristics of the adhesive (if any), and the strength of the final assembly. In this article, we describe various chemistries that have been used to obtain the wide variety of adhesives that are available.

Adhesives can be classified in many ways. In this article we they are classified loosely by strength. Thus, the article is divided into classes of adhesives that are based upon the strength of the joints that result from the use of these adhesives. The article will be divided into sections based upon the following classifications: market economics, adhesion, pressure sensitive adhesives, hot‐melt adhesives, solution‐based adhesives, structural adhesives and natural product based adhesives. This final class of adhesives is somewhat broader than the first four since it deals mainly with the source of the adhesive material rather than its strength.
Hydrogen‐Ion Activity
Authors: Durst Richard A. , Bates Roger G.
Published: December 2009

In a world in which most chemical and biological reactions occur in aqueous media, it it well recognized that the hydrogen ion is of fundamental importance. Hydrogen ions are involved in a wide variety of natural and industrial reactions, and the equilibrium position as well as the rates of these reactions are therefore dependent on hydrogen‐ion concentration. The hydrogen ion is more correctly termed hydronium ion. The hydrogen ion concentration or total acidity is obtained by titration and corresponds to the total concentration of hydrogen ions available in a solution. Two methods are used to determine pH:electrometirc and chemical indicator.The most common is electrometric and uses the the commercial pH meter with a glass electrode. The glass electrode is the hydrogen‐ion sensors in most pH measurement systems. This article gives details on the pH instrumentation and includes basic analyzers, microprocessor based pH analyzers, and smart analyzers. The indicator method is convenient when pH must be measured at room temperature with an accuracy of no greater than 0.5 pH. The measurement of pH is valuable as a leak detector, a measurement of concentration, reaction monitoring, and in industrial process control.
Superabsorbent Materials
Authors: Wang Aiqin , Wang Wenbo
Published: December 2009

Superabsorbent materials (SAMs) are hydrophilic polymer networks that can rapidly absorb water at amounts hundreds or even thousands times their own mass, and they can retain the absorbed water for a long time even under some pressure. Because of their excellent properties, SAMs are mainly used in disposable hygiene products as substitutes for traditional absorbents (cotton, sponge, wood pulp, and colloidal silica) and used in modern agriculture as water‐saving materials. Since the commercialization of the first SAM in 1978, the global yield and consumption of SAM was dramatically increased year by year, and the applications of such materials were also extended to other fields, such as wastewater treatment, medicine, construction, and sealing materials. Although SAMs are only decades old, they has developed into one of the most potential and prospective polymer materials in the market. Common SAMs are generally white sugar‐like hygroscopic materials, which can be classified as the following three types: starch‐based SAM, cellulose‐based SAM, and synthetic SAM. Today, the common commercial SAMs are cross‐linked sodium polyacrylate prepared through solution or inverse‐suspension polymerization techniques. In allusion to the drawbacks of currently prepared SAMs (including low salt‐resistance, high production cost, and poor gel strength), multiple kinds of raw materials and preparation methods were developed and adopted by manufacturers. Based on the above description, the development background, characteristics, chemical structures, type, physical and chemical properties of SAM, and the corresponding applied research works and future development prospects are introduced in this article.
Efficient Heterogeneous Dual Catalyst Systems for Alkane Metathesis
Authors: Huang Zheng , Rolfe Eleanor , Carson Emily C. , Brookhart Maurice , Goldman Alan S. , El‐Khalafy Sahar H. , MacArthur Amy H. Roy
Published: December 2009

A fully heterogeneous and highly efficient dual catalyst system for alkane metathesis (AM) has been developed. The system is comprised of an alumina‐supported iridium pincer catalyst for alkane dehydrogenation/olefin hydrogenation and a second heterogeneous olefin metathesis catalyst. The iridium catalysts bear basic functional groups on the aromatic backbone of the pincer ligand and are strongly adsorbed on Lewis acid sites on alumina. The heterogeneous systems exhibit higher lifetimes and productivities relative to the corresponding homogeneous systems as catalyst/catalyst interactions and bimolecular decomposition reactions are inhibited. Additionally, using a “two‐pot” device, the supported Ir catalysts and metathesis catalysts can be physically separated and run at different temperatures. This system with isolated catalysts shows very high turnover numbers and is selective for the formation of high molecular weight alkanes.
Morphology of poly(ethylene terephthalate) blends: An analysis under real processing conditions by rheology and microscopy
Authors: Özen İlhan , Menceloǧlu Yusuf Zi̇ya
Published: December 2009

The present work describes the formation of co‐continuous phase morphologies in uncompatibilized and compatibilized poly(ethylene terephthalate) (PET)–poly(m‐xylene adipamide) (MXD6) and PET– poly(ethylene‐co‐vinyl alcohol) (EVOH) melt‐extruded blends. Phase continuity has been determined by using the Jordhamo relationship. Viscosity values, which are essential for the calculation of the phase continuity, have been obtained by capillary rheometry. Thermal behavior of the blends has been analyzed by employing differential scanning calorimetry and phase continuity has been investigated for the noncompatibilized and the compatibilized blends by scanning electron microscopy. PET–MXD6 blends [92.35:7.65 (v/v) and 84.5:15.5 (v/v)] and PET–EVOH blends [73.63:26.37 (v/v)] exhibit droplet‐in‐matrix phase morphology, whereas uncompatibilized PET–MXD6 [75.8:24.2 (v/v)] blend has a combination of rod‐like, droplet–matrix structure, and quasi‐interpenetrating network structure. © 2009 Wiley Periodicals, Inc. Adv Polym Techn 28:173–184, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20156
Improved compatibility of EVOH/LDPE blends by γ‐ray irradiation
Authors: Li Haihong , Yin Yuan , Liu Meihua , Deng Pengyang , Zhang Wanxi , Sun Jiazhen
Published: December 2009

The change of compatibility of poly(ethylene‐co‐vinyl alcohol) (EVOH)/LDPE blends induced byγ‐ray radiation was studied. Gel extraction experiment results show that the gel fraction of blends increases linearly with the content of LDPE and reaches a maximum at 100 kGy, because neat EVOH is difficult to cross‐link by irradiation. A comparison of theoretical and experimental gel contents indicates that some EVOH molecular chains enter the LDPE gel network. The peak at 3363 cm−1 on the Fourier transform infrared spectrum of pure blend gel is assigned to typical stretching of an OH bond, which indicates that a “graft” reaction occurs in the interface between EVOH and LDPE phases during the irradiation process. Mechanical property measurement results support such a structural change. The tensile strength of cross‐linked blends increases with absorbed dose first, reaches a maximum value at 150 kGy, and then decreases with dose. A similar trend can also be observed in bending tests. © 2009 Wiley Periodicals, Inc. Adv Polym Techn 28:192–198, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20160
Sea urchin embryos exposed to thalidomide during early cleavage exhibit abnormal morphogenesis later in development
Authors: Reichard‐Brown Jan L. , Spinner Hannah , McBride Katherine
Published: December 2009

BACKGROUND: Clinical use of thalidomide has increased drastically, pushing the questions concerning the teratogenic mechanisms of this drug back to the forefront. Progress in understanding the teratogenic mechanisms has been slow, with the lack of non‐primate vertebrate animal models susceptible to the classic reduction deformities remaining a concern. Sea urchin embryos have been used as model organisms for developmental studies for the last century. Like vertebrates, they are deuterostomes and share similar developmental and signaling pathways suggesting they may be an effective system for thalidomide studies. Therefore, we tested sea urchin embryos to see if they were sensitive to the effects of thalidomide. METHODS: Sea urchin embryos were obtained using standard spawning and fertilization techniques. Thalidomide dissolved in DMSO was added to embryo cultures either at fertilization or during early cleavage. Samples of the embryos were evaluated during specific development stages. RESULTS: Lytechinus pictus embryos exposed to 400 µM thalidomide at fertilization or within a window during early cleavage (2–6 hours post‐fertilization) exhibit significant levels of abnormal embryos (60–82%) at the pluteus stage, compared to controls levels (≤10%). Strongylocentrotus purpuratus embryos exposed at initial fertilization or during early cleavage (2–6 hours post‐fertilization) exhibit similar responses with significant abnormal levels ranging from (55–70%) at pluteus stage. CONCLUSIONS: Both species of sea urchin tested were susceptible to thalidomide‐induced teratogenesis during cleavage (4–16 cell stages). This response during cleavage stages warrants further study and indicates that sea urchin embryos may prove to be a useful tool for studying thalidomide effects early in development. Birth Defects Res (Part B) 86:496–505, 2009. © 2009 Wiley‐Liss, Inc.
Assessment of COMT isolation by HIC using a dual salt system and low temperature
Authors: Nunes V. S. , Bonifácio M. J. , Queiroz J. A. , Passarinha L. A.
Published: December 2009

Sodium citrate (SC) and low temperatures between 7 and 5°C are effective in suppressing aggregation of proteins and may be beneficial to be included during a purification process. In this work, we analyzed the application of dual salt system, ammonium sulfate (AS) and SC on binding and elution conditions of recombinant hSCOMT on typical HIC sorbents. Specifically in butyl and octyl supports, the use of, respectively, 300 mm AS/200 mm SC and 25 mm AS/25 mm SC in the loading buffer resulted in complete binding of COMT. Elution was obtained by decreasing the ionic strength to 0 M of salt. For the delineate goal, it also favorably increased the support chain length while a consequent decrease in the dual ionic strength was observed for hSCOMT retention. In the presence of dual salt systems octyl media exhibited classic HIC behavior, good protein selectivity, an excellent purification factor and reduced denaturation effects of hSCOMT observed with higher salt concentrations. Also the inclusion of temperature control during the elution step appears to be advantageous for greater activity recovery without enzyme aggregation. In fact, these results could allow the prediction of most stabilizing conditions for this termolabile enzyme on the chromatographic stage, regarding salt types and therefore effectiveness to improve HIC selectivity and desirable purity on the target fractions. Copyright © 2009 John Wiley & Sons, Ltd.
Trans‐septal closure of a right pulmonary artery to left atrial communication
Authors: Ramakrishnan Sivasubramanian , Shivdas Sunil , Kothari Shyam S.
Published: December 2009

Right pulmonary artery–left atrial communication is a rare anomaly and is characterized by significant cyanosis and normal auscultation of the heart. Interventional closure of the fistula using occluder devices and coils have been rarely reported. We report an easy method of closure of the communication through trans‐septal approach using an Amplatzer duct occluder. © 2010 Wiley‐Liss, Inc.
Failure of drug eluting stents presented as definite stent thrombosis
Authors: Vaknin‐Assa Hana , Assali Abid , Lev Eli I. , Ukabi Shimrit , Tamir Bental , Kornowski Ran
Published: December 2009

Background: Stent thrombosis (ST) risk may persist long after a successful drug eluting stents (DES) implantation. Objective:We evaluated the incidence, timing, and clinical outcomes of patients with early (≤30 days), late (>30–365 days), and very late (>365 days) angiographically proven ST related to DES. Methods: Between 2004 and 2009, 4,396 patients underwent percutaneous coronary interventions (PCI) with DES implantations. This 5‐year follow‐up study included 38 patients (mean age 60 ± 12 years; 76% males) who were readmitted with confirmed ST diagnoses. Clopidogrel therapy was prescribed for 3–12 months. Clinical follow‐ups were conducted at 1 and 6 months following ST events. Results:The overall ST rate was 0.9% (38/4,396); the late ST rate was 0.7%. There were four (11%) early and 34 (89%) late events; the time interval to thrombosis was 21 ± 14 months (range 0.13–60 months). Two patients had stent fractures associated with ST, 37% had diabetes, and 68% presented with ST‐elevation myocardial infarctions (MI). One third was treated with clopidogrel at the ST event. Three patients (8%) had recurrent late ST events and two died within 1 month after the ST event (5%). At 6 months, we observed a 26% major adverse cardiac event rate, and the overall cardiac mortality rate was 8%. Conclusions: In our series, ST occurred infrequently (0.9%), mostly between 1 and 3 years after the period recommended for dual anti‐platelet pharmacotherapy, and it is associated with substantial clinical consequences. © 2010 Wiley‐Liss, Inc.
Transradial complex left main trifurcation intervention
Authors: Hussein Hesham , Fang Hsiu‐Yu , Wu Chiung‐Jen
Published: December 2009

Trifurcation lesions, especially around the left main coronary artery (LMCA), are occasionally encountered. Complex lesions, involving the bifurcation or the trifurcation of the unprotected LMCA, represent a real challenge for interventional cardiologists. Trifurcation lesions intervention reported to have high overall major adverse cardiovascular events, and require the use of various complex interventional techniques, for example, large guiding catheters to accommodate three wires guiding simultaneously inflated balloons or stents. Here, we report a case of successful percutaneous coronary intervention supported by pre‐and post‐intravascular ultrasound imaging, on an LMCA trifurcation using a 6F guiding catheter via transradial approach. © 2010 Wiley‐Liss, Inc.
Selective use of embolic protection devices during saphenous vein grafts interventions: A single‐center experience
Authors: Lavi Shahar , Ivanov Joan , Appleby Clare E. , Seidelin Peter H. , Mackie Karen , Schwartz Leonard , Džavík Vladimír
Published: December 2009

Objectives: To report on outcomes with selective use of embolic protection devices (EPD) during percutaneous coronary intervention (PCI) to saphenous vein grafts (SVG). Background: PCI to SVG is associated with increased risk and the use of EPD is recommended in this setting. Methods: Angiographic and clinical outcomes were prospectively obtained from 534 consecutive patients who underwent PCI to SVG with or without EPD at a tertiary cardiac centre. Long‐term outcomes were obtained by linkage to a provincial registry. Results: EPD, deployed in 198 of 373 SVGs (53%) suitable for deployment of a distal EPD, were used more often in ectatic (33% vs. 19%, P = 0.003), ulcerated (17% vs. 9%, P = 0.03), thrombotic (26% vs. 10%, P < 0.0001) vein grafts, with longer degenerated segments (P = 0.002), and in lesions involving the body of the graft (85% vs. 66%, P < 0.0001), and less with lesions involving the graft ostium (29% vs. 44%, P = 0.003). Patients suitable for but not receiving EPD tended to be more likely to have a periprocedural myocardial infarction. During 3 years of follow‐up, 49% of the patients had a cardiovascular event. Cumulative mortality was 8.4%, 18.8% and 14.7% in patients unsuitable for distal EPD, suitable but without EPD, and with EPD (p = 0.11). Nonuse of EPD was an independent predictor of MACE at 3 years. (P = 0.02). Conclusions: Selective use of EPD is associated with low in‐hospital cardiovascular event rates. Long‐term outcomes are manifested by a high rate of events, especially in patients with SVG's suitable for but not receiving EPD. This suggests that routine use of distal EPD may be warranted in unselected patients with suitable SVG anatomy. © 2010 Wiley‐Liss, Inc.