bluuebunny/crossref_metadata_2025 huggingface dataset:
Retrospective Study of 25 Cases of Keratocystic Odontogenic Tumor: Epidemiology and Treatment
Authors: Schussel Juliana L , Stramandinoli Roberta T , Dissenha Jose Luis , Avila Lucia FC , Sassi Laurindo M
Published: November 2011

Aim

Keratocystic odontogenic tumor (KOT) is a benign odontogenic neoplasm with locally aggressive behavior and high recurrence rates. It is associated with nevoid basal cell carcinoma syndrome which usually has a more rapid growth. The aim of the study is to report the experience of our service on diagnosis and treatment of KOT.

Materials and methods

Twenty-five cases of KOT were diagnosed between the years of 1989 and 2006. Demographic data was collected as well as diagnose and treatment.

Results

Fifty-six percent were female with a mean age of 33 years old. Seventy percent occurred in mandibula and all received surgical treatment, associate or not with adjuvant therapy, such as cryotherapy and Carnoy's solution. Recidive was observed in 48% of cases with a mean period of time of 18 months.

Conclusion

Our data analysis showed the importance of previous diagnosis before enucleation procedure and long-term follow-up for recurrence early detection. Recurrence incidence is more frequent on first year after diagnosis.

Clinical significance

KOT is a benign tumor with local aggressive behavior and therefore its treatment must consider the high index of recidive. Reports of protocol treatment should raise new discussion to decrease recurrence rates.

How to cite this article

Schussel JL, Stramandinoli RT, Dissenha JL, Avila LFC, Sassi LM. Retrospective Study of 25 Cases of Keratocystic Odontogenic Tumor: Epidemiology and Treatment. J Contemp Dent Pract 2011;12(2):100-103.
Apical Force Distribution due to Orthodontic Forces: A Finite Element Study
Authors: Mathur Anirudh K , Sarmah Anirban , Pai Vinaya S , Chandrashekar G
Published: November 2011

Aim

This finite element study was conducted to calculate the distribution of stresses in the periodontal ligament when various orthodontic forces were applied, with emphasis on the effect on root apex.

Materials and methods

An in vitro finite element method was used to construct a three-dimensional finite element model of a maxillary central incisor, its periodontal ligament and alveolar bone was constructed on the basis of average anatomic morphology. To this model, five types of orthodontic forces namely tipping, bodily movement, intrusion, extrusion and rotations were applied at various points on the crown of the tooth model. After the application of the forces, initial stress and initial displacements of the periodontal ligament were evaluated. The principal stress obtained on the periodontal ligament due to various orthodontic loadings on the maxillary central incisor was analyzed using ANSYS 10 finite element software.

Results

It showed that the greatest amount of relative stress at the apex of maxillary central incisor occurred with intrusion, extrusion and rotation. Bodily movement and tipping forces produce stress concentrated at the alveolar crest and not at the root apex.

Conclusion

Clinical implications of this study suggest that if the clinician is concerned about placing heavy stresses on the root apex, then vertical and rotational forces must be applied with caution.

Clinical Significance

If heavy stresses are to be placed on the root apex, then vertical and rotational forces must be applied with caution during orthodontic therapy.

How to cite this article

Mathur AK, Gupta V, Sarmah A, Pai VS, Chandrashekar G. Apical Force Distribution due to Orthodontic Forces: A Finite Element Study. J Contemp Dent Pract 2011;12(2):104-108.
Prosthetic Management of Edentulous Mandible using Endosseous Implants and Overdentures
Authors: Saleem Mohammed , Saleem Rayeesa , Meshack Rufus Allwyn
Published: November 2011

The choice of a suitable prosthesis for a specific case is determined to a great extent by the underlying residual bone as well as the mucosa. Also of significance are the expectations and demands of the patient from the prosthesis. The following case report discusses the rehabilitation of a complete edentulous mandibular arch with an implant retained mandibular over denture.

Clinical Significance

Implant retained fixed or removable prostheses are good treatment options in patients who have a compromised edentulous foundation.

How to cite this article

Saleem M, Saleem R, Meshack RA, Guru R. Prosthetic Management of Edentulous Mandible using Endosseous Implants and Overdentures. J Contemp Dent Pract 2011;12(2):135-137.
Management of Severe Class II Malocclusion with Fixed Functional Appliance: Forsus
Authors: Vijayalakshmi PS , Veereshi AS
Published: November 2011

Background

Management of class II malocclusion in adolescent patients by growth modulation is one of the most debated topics in orthodontics. Noncompliance has been a major concern for orthodontists.

Case report

This case report describes the management of severe class II malocclusion in adolescent patient using functional appliance system—Forsus to correct class II problems, which is clipped on to bands. This appliance has several advantages, as the patient cannot remove it. It acts on the teeth and jaws for 24 hours each day, patient cooperation is not a problem, and as a result the treatment time is short. There is lot of controversy about the use of functional appliances.

Conclusion

This case report illustrates that even today, functional appliances have a significant role in the management of class II malocclusion by using growth modulation. The growth modulation minimizes the necessity of extraction of permanent teeth and probably orthognathic surgery.

Clinical significance

Functional appliances have a significant role in the management of class II malocclusion. The growth modulation minimizes the necessity of extraction of permanent teeth and probably orthognathic surgery.

How to cite this article

Vijayalakshmi PS, Veereshi AS. Management of Severe Class II Malocclusion with Fixed Functional Appliance: Forsus. J Contemp Dent Pract 2011; 12(3):216-220.
Infant-Mother Attachment Can Be Improved through Group Intervention: A Preliminary Evaluation in Spain in a Non-Randomized Controlled Trial
Authors: Torres Bárbara , Alonso-Arbiol Itziar , Cantero María José , Abubakar Amina
Published: November 2011

The quality of infant-mother attachment has been linked to competence in different domains of child development. Research indicates that early intervention can enhance the quality of infant-mother attachment, though its efficacy in a group format has yet to be evaluated. The current study is aimed at examining the usefulness of a group intervention in enhancing infant-mother attachment. An intervention aimed at addressing aspects such as maternal responsivity, sensitivity and childrearing behaviour was developed by the researchers and experienced psychologists. The intervention spanned a period of 14 months starting from the third quarter of pregnancy. The intervention was evaluated among 24 mothers from the Basque region of Spain. The sample consisted of children of both genders in a similar proportion: 45.8% were boys and 54.2% were girls. The children in this sample were full-term born and did not present symptoms of any serious pre- or postnatal complications. The intervention had a statistically non-significant medium effect. Infants whose mothers had received the intervention showed higher rates of secure attachment compared to children from the control group, as assessed by the Strange Situation observation procedure. A potentially significant confounding variable, maternal attachment, was balanced across the intervention and comparison groups. We can tentatively point out that a group intervention may enhance the quality of infant-mother attachment. Nevertheless, because the study design was not randomized, the results of this study remain preliminary and need replication in a full randomized controlled trial designed study.
Father Involvement and Marital Relationship during Transition to Parenthood: Differences between Dual and Single-Earner Families
Authors: Menéndez Susana , Hidalgo Mª Victoria , Jiménez Lucía , Moreno Mª Carmen
Published: November 2011

Research into the process of becoming mother or father shows very conclusively that this important life transition is accompanied by both a decrease in marital quality and a more traditional division of labour. In this paper these changes are analyzed with special emphasis on the relationships between them and exploring the role played in this process by the mother's work status. Results showed a significant link between the development of marital quality and violated expectations regarding father involvement on childrearing. Dual-earner families were characterized by a specific pattern of changes, with greater stability than single-earner families in marital and parental roles during transition to parenthood and a significant role played by spouse support as a partner, but not as a parent.
Risk Profiles and Peer Violence in the Context of School and Leisure Time
Authors: Valero Rosa Pulido , Seoane Gema Martín , Molina Beatriz Lucas
Published: November 2011

Though violence at school is by no means a new phenomenon, there has been growing social and scientific concern about this issue in recent years. The present study builds on prior analysis of the roles adolescents play in peer harassment, and the relationship between violence occurring at school and during free time. A representative sample of students between the ages of 14 and 18 was selected in the Community of Madrid (N = 1622) through random cluster sampling (school was the unit of analysis). Participants completed the C.E.V.E.O. questionnaire, which presents fifteen situations involving peer violence. The results reveal a relationship between violent situations occurring at school and during free time, and between the roles of aggressor and victim during free time. A profile analysis yielded three different categories: the “minimal violence exposure” type (1126 adolescents), the “psychological violence exposure” type (413 adolescents), and the “high risk of violence” type (83 adolescents). Judging from these results, we posit that interventions must be designed which tailor to each group and their respective risk situations.
Hand Gestures and Perceived Influence in Small Group Interaction
Authors: Maricchiolo Fridanna , Livi Stefano , Bonaiuto Marino , Gnisci Augusto
Published: November 2011

A laboratory study was carried out to establish the relative importance of verbal and gestural behavior, as well as their interaction, for perceived social influence in more or less competitive small groups. Forty women (psychology students) participated in leaderless small group discussions of different sizes (fourmember and eight-member): at the end, each member rated the perceived influence in decision-making of every other member. Verbal dominance coding is based on traditional quantitative conversational dominance (number of talk turns). Gestural coding (conversational, ideational, object-adaptor, self-adaptor gestures) is based on classical gesture classifications. Beside a substantial effect of verbal dominance, the main result is that frequency of object-adaptors and conversational (only in large groups) and ideational (in both small and large groups) gestures increases perceived influence scores particularly when the verbal dominance of the speaker is low.
Consequences of Job Insecurity and the Moderator Role of Occupational Group
Authors: Miana Beatriz Sora , González-Morales M. Gloria , Caballer Amparo , Peiró José M.
Published: November 2011

In recent decades, transformations in organizations and the labour market have produced an increase in employee job insecurity. In response to this situation, workers present different negative reactions. However, the intensity of these reactions varies across studies that have investigated the outcomes of job insecurity. One possible explanation for this inconsistency may lie in the influence of other factors, such as the occupational group (Sverke et al., 2002). The aim of this study is to provide additional evidence about the relationship between job insecurity and its outcomes (i.e., life satisfaction, job satisfaction, perceived performance and organizational commitment), and examine the moderator role of occupational group in this relationship. The sample was composed of 321 employees from different Spanish organizations. The results showed that job insecurity was directly and negatively related to life satisfaction, job satisfaction and organizational commitment, and they suggest that occupational group moderated relations between job insecurity and three studied outcomes. In the case of life satisfaction and perceived performance, this relationship was stronger among blue collar workers. The relationship between job insecurity and job satisfaction was stronger in white collar workers. The implications and limitations of this study are discussed.
Spanish Validation of the Acceptance of Modern Myths about Sexual Aggression Scale (AMMSA)
Authors: Megías Jesús L. , Romero-Sánchez Mónica , Durán Mercedes , Moya Miguel , Bohner Gerd
Published: November 2011

Two studies were conducted with college students to validate the Spanish-language version of the “Acceptance of Modern Myths about Sexual Aggression” scale (AMMSA) (Gerger, Kley, Bohner & Siebler, 2007). This scale assesses modern myths about sexual aggression in a subtle way. In Study 1, 305 students completed the Spanish AMMSA and other scales with related content. In Study 2, 263 participants completed the Spanish AMMSA and answered questions about a hypothetical sexual assault perpetrated by a young man against a female acquaintance. The Spanish AMMSA showed high internal consistency and adequate evidence of validity in both studies. Compared to traditional scales of rape myth acceptance, mean scores on the AMMSA were higher and their distributions more closely approximated normality. These findings suggest that the Spanish version of the AMMSA scale is a useful instrument to study the social perception of sexual aggression.
Factorial Validity of the Job Expectations Questionnaire in a Sample of Mexican Workers
Authors: Villa-George Fabiola Itzel , Moreno-Jiménez Bernardo , Rodríguez-Muñoz Alfredo , Uribe Jessica Villalpando
Published: November 2011

The aim of this study was to examine the factorial validity of the Job Expectations Questionnaire (Cuestionario de Expectativas Laborales CEL) in a sample of Mexican workers. Following a cross validation approach, two samples were used in the study. The first sample consisted of 380 professionals who mainly performed administrative work in the Health Services in Puebla-Mexico. The second sample comprised 400 health professionals from the Hospital de la Mujer in Puebla-Mexico. Exploratory factor analysis yielded a three-factor solution, accounting for 51.8% of the variance. The results of confirmatory factorial analysis indicate that the three-factor model provided the best fit with the data (CFI = .96, GFI = .95, NNFI = .95, RMSEA = .04), maintaining the structure with 12 items. The reliability of the questionnaire and the diverse subscales showed high internal consistency. Significant correlations were found between job expectations and autonomy, vigor, dedication, and absorption, providing evidence of its construct validity. The evaluation of the psychometric qualities confirms this questionnaire as a valid and specific instrument to measure job expectations.
Mapping the Multi-Industry Terrain of Nanotechnology Entrepreneurship
Authors: Noyes Erik
Published: November 2011

This paper examines the multi-industry terrain of nanotechnology entrepreneurship. The core contribution is visual as well as theoretical – the analysis shows the multi-industry ‘footprint’ of nanotechnology entrepreneurial ventures that launch products into different industries. Dominant theory on industry emergence by Garud and Van de Ven (1987) takes a single-industry focus. By contrast, this research suggests that entrepreneurs focusing on radical technologies such as nanotechnology may straddle various industries in an attempt to peer into and develop inter-linkages among different entrepreneurial opportunities and industry contexts. A theoretical contribution, the research challenges Garud and Van de Ven's single-industry scope for understanding industry emergence, particularly in the context of multi-industry opportunities.
How Do Women Entrepreneurs Use the Virtual Network Facebook?
Authors: Constantinidis Christina
Published: November 2011

This paper examines the views and attitudes of a sample of 228 female entrepreneurs in Belgium towards the virtual social network Facebook. It uses statistical analysis to evaluate the impact of their gendered sector of activity and of their self-perceptions on: how Facebook is perceived as responding to gender-related difficulties; how Facebook is used in terms of objectives and activities; how Facebook supports women's networks; and the outcomes of Facebook for women-owned businesses. The results highlight significant differences according to women's sectors of activity and self-perceptions with regard to how Facebook is perceived and used. They support the idea of an active posture of women entrepreneurs, allowing for action to be taken to deconstruct and counterbalance existing gender dynamics. The paper highlights certain implications for public and private initiatives and underlines the potential of this and other virtual social networking sites for women's entrepreneurship.
Testing Oligopolistic Behaviors: Conduct and Cost in Taiwan's Flour Market
Authors: Ma Tay‐Cheng
Published: November 2011

Testing the validity of the new empirical industrial organization (NEIO) proposition is often made more complicated by a lack of reliable cost data. Nevertheless, the author takes advantage of a more sophisticated dataset to directly measure cost in Taiwan's flour market. In contrast to the previous findings, the evidence indicates that the NEIO technique performs reasonably well in estimating both conduct and cost parameters.
Regional variation in prevalence of oral cleft live births in the Netherlands 1997–2007: Time‐trend analysis of data from three Dutch registries
Authors: Rozendaal Anna M. , Mohangoo Ashna D. , Ongkosuwito Edwin M. , Buitendijk Simone E. , Bakker Marian K. , Vermeij‐Keers Christl
Published: November 2011

The Eurocat registry Northern Netherlands (NNL) has been used in regional context, as well as in national/international context, to describe the epidemiology of oral clefts (OC). However, the region NNL seems to have prevalence data different from Dutch national registries and certain other European areas. This may be due to differences in registration methods or geographical variation. To investigate whether the prevalence of OC live births varies regionally in the Netherlands, we established time trends for NNL and the rest of the Netherlands over 1997–2007 using data from two national registries (the OC Registry and The Netherlands Perinatal Registry) and a regional registry (Eurocat NNL). We found that the overall live‐birth prevalence—comprising cleft lip/alveolus ± cleft palate and cleft palate only—was significantly higher in NNL (15.1–21.4 per 10,000) than in the rest of the Netherlands (13.2–16.1 per 10,000). None of the registries showed significant trends for NNL, whereas both national registries showed that the live‐birth prevalence of cleft lip/alveolus ± cleft palate decreased significantly in the rest of the Netherlands. Despite some differences in prevalence between the registries, they showed similar regional variation in prevalence and trends. In conclusion, the prevalence of OC live births varies significantly in the Netherlands, not only between but also within registries. This underlines that extrapolation of regional cleft data should be done with caution. To further investigate OC etiology and evaluate preventive strategies, future studies should consider geographical differences—between and within countries—regarding the various cleft sub‐phenotypes among live births, stillbirths, and pregnancy terminations. © 2011 Wiley Periodicals, Inc.
A patient with a mild holoprosencephaly spectrum phenotype and heterotaxy and a 1.3 Mb deletion encompassing GLI2
Authors: Kevelam Sietske H.G. , van Harssel Jeske J.T. , van der Zwaag Bert , Smeets Hubertus J.M. , Paulussen Aimee D.C. , Lichtenbelt Klaske D.
Published: November 2011

Loss‐of‐function mutations of GLI2 are associated with features at the mild end of the holoprosencephaly spectrum, including abnormal pituitary gland formation and/or function, and craniofacial abnormalities. In addition patients may have branchial arch anomalies and polydactyly. Large, microscopically visible, interstitial deletions spanning 2q14.2 have been reported in patients with multiple congenital anomalies and intellectual disability. We report here on a patient with a mild holoprosencephaly spectrum phenotype (bilateral cleft lip and palate and abnormal pituitary gland formation with panhypopituitarism) and normal psychomotor development, who was found to carry a 1.3 Mb submicroscopic heterozygous deletion in 2q14.2, encompassing the GLI2 gene. We review the genotype and phenotype of previously published probands with GLI2 aberrations. Our findings confirm the association of haploinsufficiency of GLI2 and mild HPE spectrum features. Consistent with prior reports, we observed incomplete penetrance of the deletion in the family, illustrating the multifactorial etiology of holoprosencephaly spectrum features. In addition to the holoprosencephaly spectrum features, the proband had heterotaxy of the abdominal organs. Mutations in the known heterotaxy genes (NODAL, ZIC3 and CFC1) were excluded. The deletion contains five genes, in addition to GLI2, including the EPB4.1l5 gene. Based on findings in Epb4.1l5 mutant mice we hypothesize that Epb4.1l5 is a candidate gene for the heterotaxy observed in the proband. © 2011 Wiley Periodicals, Inc.
In‐frame multi‐exon deletion of SMC1A in a severely affected female with Cornelia de Lange Syndrome
Authors: Hoppman‐Chaney Nicole , Jang Jin Sung , Jen Jin , Babovic‐Vuksanovic Dusica , Hodge Jennelle C.
Published: November 2011

Cornelia de Lange Syndrome (CdLS) is a genetically heterogeneous disorder characterized by dysmorphic facial features, cleft palate, limb defects, growth retardation, and developmental delay. Approximately 60% of patients with CdLS have an identifiable mutation in the NIPBL gene at 5p13.2. Recently, an X‐linked form of CdLS with a generally milder phenotype was attributed to mutation of the structural maintenance of chromosomes 1A gene (SMC1A) at Xp11.22. Relatively few CdLS patients with mutations in SMC1A are known; female carriers have minor facial dysmorphism and cognitive deficiency without major structural abnormalities. To date, all mutations identified in SMC1A are missense or small in‐frame deletions that preserve the open reading frame of the gene and likely have a dominant‐negative effect. We report on a female with monosomy X mosaicism and a phenotype suggestive of a severe form of CdLS who presented with growth and mental retardation, multiple congenital anomalies, and facial dysmorphism. Array CGH confirmed mosaic monosomy X and identified a novel deletion of SMC1A spanning multiple exons, suggesting a possible loss‐of‐function effect. Sequencing of both genomic and cDNA demonstrated an 8,152 bp deletion of genomic DNA from exon 13 to intron 16. Although a loss‐of‐function effect cannot be excluded, the resulting mRNA remains in‐frame and is expressed in peripheral blood lymphocytes, suggesting a dominant‐negative effect. We hypothesize that the size of this deletion compared to previously reported mutations may account for this patient's severe CdLS phenotype. The presence of mosaic monosomy X may also modify the phenotype. © 2011 Wiley Periodicals, Inc.
A re‐examination of the use of ethnicity in prenatal carrier testing
Authors: Ross Lainie Friedman
Published: November 2011

In April 2011, the American Congress of Obstetricians and Gynecologists (formerly the American College of Obstetrics and Gynecology [ACOG]), updated its policy on carrier screening for cystic fibrosis and proposed that because of the increasing difficulty in assigning a single ethnicity to individuals, “It is reasonable, therefore to offer CF carrier screening to all patients.” However, ACOG continues to use ethnicity in its guidelines about carrier testing for autosomal recessive disorders like sickle cell disease (SCD) and Tay‐Sachs disease (TSD). This practice is in marked contrast with newborn screening (NBS) which is universally provided for all conditions. In this manuscript, I evaluate the discrepant role of ethnicity in NBS and carrier screening. I argue that ACOG needs to adopt the position it now takes for CF regarding prenatal carrier testing for all conditions. To promote equity in prenatal testing decision making, health care policies must acknowledge the diversity of the populations that we serve and empower all women and couples to make more fully informed reproductive decisions by offering prenatal carrier testing to all. © 2011 Wiley Periodicals, Inc.
Renal anomalies in Alagille syndrome: A disease‐defining feature
Authors: Kamath Binita M. , Podkameni Gisele , Hutchinson Anne L. , Leonard Laura D. , Gerfen Jennifer , Krantz Ian D. , Piccoli David A. , Spinner Nancy B. , Loomes Kathleen M. , Meyers Kevin
Published: November 2011

Alagille syndrome (ALGS) is an autosomal dominant condition, primarily caused by mutations in JAGGED1. ALGS is defined by cholestatic liver disease, cardiac disease and involvement of the face, skeleton, and eyes with variable expression of these features. Renal involvement has been reported though not formally described. The objective of this study was to systematically characterize the renal involvement in ALGS. We performed a retrospective review of 466 JAGGED1 mutation‐positive ALGS patients. Charts were reviewed for serum biochemistries, renal ultrasounds or other imaging, urinalysis, and clinical reports from pediatric nephrologists. The clinical data were reviewed by two pediatric hepatologists and a pediatric nephrologist. Of 466 charts reviewed we found 187 yielded evaluable renal information. Of these, 73/187 were shown to have renal involvement, representing 39% of the study cohort. Renal dysplasia was the most common anomaly seen. Genotype analysis of the JAGGED1 mutations in the patients with and without renal involvement did not reveal an association with mutation type. From the study we concluded that renal involvement has a prevalence of 39% in ALGS in our evaluable patients. Renal dysplasia is the most common renal anomaly. This finding correlates with the known role of the Notch pathway in glomerular development. Since renal disease of the type seen in ALGS can impair growth and impact liver transplantation, there is a clear need for a prospective study of renal involvement in ALGS and the development of guidelines for evaluation and management. These data also suggest that renal involvement be considered the sixth defining criterion for ALGS. © 2011 Wiley Periodicals, Inc.
Retrospective analysis of the clinical manifestations and survival of Korean patients with mucopolysaccharidosis type II: Emphasis on the cardiovascular complication and mortality cases
Authors: Sohn Young Bae , Choi Eun Wha , Kim Su Jin , Park Sung Won , Kim Se‐Hwa , Cho Sung‐Yoon , Jeong Soo In , Huh June , Kang I‐Seok , Lee Heung Jae , Paik Kyung‐Hoon , Jin Dong‐Kyu
Published: November 2011

Hunter syndrome (mucopolysaccharidosis II, MPS II) is a rare, X‐linked disorder of glycosaminoglycan (GAG) catabolism caused by a deficiency in the activity of the lysosomal enzyme, iduronate‐2‐sulfatase (I2S). In this study, the medical records of 75 Korean patients with Hunter syndrome (74 males, 1 female) were retrospectively reviewed to investigate the frequency of organ involvement and survival at a single center. The three most common symptoms of organ involvement were hepatosplenomegaly (99%), facial dysmorphism (97%), and frequent otitis media (91%). Cardiovascular involvement was also common including valvular abnormalities (89%), left ventricular hypertrophy (68%), and hypertension (30%). The 19 patients who died had a median age of 16.8 years at the time of death. Four of them died within 1 year of the start of enzyme replacement therapy; autopsy showed myocardial infarction with severe coronary artery disease in one patient. Two other patients died due to pneumonia and sleep apnea. In one case, the cause of death was not investigated. The high incidence of hypertension, and the presence of valvular heart disease indicates that close cardiac monitoring is mandatory in all patients with Hunter syndrome, especially relatively older patients even if they are being treated with enzyme replacement therapy. © 2011 Wiley Periodicals, Inc.
Duplication of the ZIC2 gene is not associated with holoprosencephaly
Authors: Jobanputra Vaidehi , Burke Alanna , Kwame Anyane‐Yeboa , Shanmugham Anita , Shirazi Maryam , Brown Stephen , Warburton Peter E. , Levy Brynn , Warburton Dorothy
Published: November 2011

Cytogenetic testing using genomic microarrays presents a clinical challenge when data regarding the phenotypic consequences of the genomic alteration are not available. We describe a chromosome 13q32.3 duplication discovered by microarray testing in a fetus with a prenatally detected apparently balanced de novo translocation 46,XY,t(2;13)(q37;q32). Microarray analysis on the fetal DNA showed duplications of 384 and 564 kb at the breakpoint regions on chromosomes 2q37.3 and 13q32.3, respectively. There were no disease‐associated genes in the duplicated region on chromosome 2q37. The duplicated region on chromosome 13q contains the ZIC2 gene. Haploinsufficiency of ZIC2 is known to cause holoprosencephaly and other brain malformations. Studies in the mouse models have suggested that over expression of ZIC2 may also lead to brain malformations. Fetal MRI of the brain was normal and the family elected to continue the pregnancy. An apparently normal baby was born at term. At 3 months of age a physical exam showed no abnormalities and no developmental delay. This report shows that duplication of ZIC2 is not necessarily associated with brain malformations. We also describe the phenotype from four additional patients with duplications of the region of chromosome 13 containing ZIC2 and three previously described patients with supernumerary marker chromosomes derived from distal chromosome 13. None of the eight patients had holoprosencephaly or brain malformations, indicating that duplication of ZIC2 is not associated with brain anomalies. This information will be useful for counseling in other occurrences of this duplication identified by microarray. © 2011 Wiley Periodicals, Inc.
Vestibular schwannomas occur in schwannomatosis and should not be considered an exclusion criterion for clinical diagnosis
Authors: Smith Miriam J. , Kulkarni Anjana , Rustad Cecilie , Bowers Naomi L. , Wallace Andrew J. , Holder Susan E. , Heiberg Arvid , Ramsden Richard T. , Evans D. Gareth
Published: November 2011

Schwannomatosis is a recently delineated inherited condition that has clinical overlap with neurofibromatosis type 2 (NF2). Diagnostic criteria have been developed to distinguish schwannomatosis from NF2, but the existence of mosaic NF2, which may closely mimic schwannomatosis, makes even these criteria problematic. In particular, it is not clear why there is a relative sparing of the cranial nerves from schwannomas in schwannomatosis. We have identified two individuals with schwannomatosis and a unilateral vestibular schwannoma (VS), where a diagnosis of NF2 has been excluded. A third case with an identified SMARCB1 mutation was reported by two radiologists to have a VS, but this was later confirmed as a jugular schwannoma. These cases question whether the current exclusion of a VS from the clinical diagnosis of schwannomatosis is justified. © 2011 Wiley Periodicals, Inc.
Terpene Biosynthesis: Modularity Rules
Authors: Oldfield Eric , Lin Fu‐Yang
Published: November 2011

Terpenes are the largest class of small‐molecule natural products on earth, and the most abundant by mass. Here, we summarize recent developments in elucidating the structure and function of the proteins involved in their biosynthesis. There are six main building blocks or modules (α, β, γ, δ, ε, and ζ) that make up the structures of these enzymes: the αα and αδ head‐to‐tail trans‐prenyl transferases that produce trans‐isoprenoid diphosphates from C5 precursors; the ε head‐to‐head prenyl transferases that convert these diphosphates into the tri‐ and tetraterpene precursors of sterols, hopanoids, and carotenoids; the βγ di‐ and triterpene synthases; the ζ head‐to‐tail cis‐prenyl transferases that produce the cis‐isoprenoid diphosphates involved in bacterial cell wall biosynthesis; and finally the α, αβ, and αβγ terpene synthases that produce plant terpenes, with many of these modular enzymes having originated from ancestral α and β domain proteins. We also review progress in determining the structure and function of the two 4Fe‐4S reductases involved in formation of the C5 diphosphates in many bacteria, where again, highly modular structures are found.
Synthesis and characterization of novel core‐shell magnetic nanogels based on 2‐acrylamido‐2‐methylpropane sulfonic acid in aqueous media
Authors: Atta Ayman M.
Published: November 2011

Ultrafine well‐dispersed Fe3O4 magnetic nanoparticles were directly prepared in aqueous solution using controlled coprecipitation method. The synthesis of Fe3O4/poly (2‐acrylamido‐2‐methylpropane sulfonic acid) (PAMPS), Fe3O4/poly (acrylamide‐co‐2‐acrylamido‐2‐methylpropane sulfonic acid) poly(AM‐co‐AMPS) and Fe3O4/poly (acrylic acid‐co‐2‐acrylamido‐2‐methylpropane sulfonic acid) poly(AA‐co‐AMPS) ‐core/shell nanogels are reported. The nanogels were prepared via crosslinking copolymerization of 2‐acrylamido‐2‐methylpropane sulfonic acid, acrylamide and acrylic acid monomers in the presence of Fe3O4 nanoparticles, N,N′‐methylenebisacrylamide (MBA) as a crosslinker, N,N,N′,N′‐tetramethylethylenediamine (TEMED) and potassium peroxydisulfate (KPS) as redox initiator system. The results of FTIR and 1H‐NMR spectra indicated that the compositions of the prepared nanogels are consistent with the designed structure. X‐ray powder diffraction (XRD) and transmission electron microscope (TEM) measurements were used to determine the size of both magnetite and stabilized polymer coated magnetite nanoparticles. The data showed that the mean particle size of synthesized magnetite (Fe3O4) nanoparticles was about 10 nm. The diameter of the stabilized polymer coated Fe3O4 nanogels ranged from 50 to 250 nm based on polymer type. TEM micrographs proved that nanogels possess the spherical morphology before and after swelling. These nanogels exhibited pH‐induced phase transition due to protonation of AMPS copolymer chains. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Thermal properties and adhesion strength of amorphous poly(α‐olefins)/styrene–ethylene–butylene copolymer/terpene hot‐melt adhesive
Authors: Kim Jae‐Ho , Kim Ho‐Gyum , Lim Jeoung‐Cheol , Cho Kwang‐Soo , Min Kyung‐Eun
Published: November 2011

The thermal stability and adhesion properties, such as lap‐shear strength of hot‐melt adhesives were obtained from amorphous poly(α‐olefins) and thermoplastic rubber [styrene–ethylene–butylene copolymer (SEBS)] blends. The addition of SEBS increased the toughness and viscosity and decreased the lap‐shear strength of the hot‐melt adhesive. Terpene tackifier resin offered enhanced lap‐shear strength; this was more effective when combined tackifier resin was added on the hot‐melt adhesive. Only a small amount of wax and antioxidant affected the thermal stability and lap‐shear strength of the hot‐melt adhesive. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Development of electroless silver plating on Para‐aramid fibers and growth morphology of silver deposits
Authors: Zhang Huiru , Zou Xinguo , Liang Jingjing , Ma Xiao , Tang Zhiyong , Sun Jinliang
Published: November 2011

The development of a conductive fiber with flame resistance is an urgent concern particularly in national defense and other specialized fields. Aramid fibers (para‐ or meta‐) exihibit high strength and excellent fire resistance. Electroless silver plating on para‐aramid fibers and growth morphology of silver deposits was investigated in the present work. The surface of para‐aramid fibers was roughened using sodium hydride/dimethyl sulfoxide to guarantee successful electroless plating. Two complexing agents (ethylene diamine/ammonia) and two reducing agents (glucose/seignette salt) were used for the electroless silver plating bath design. Structure and properties of the resulting silver‐deposited para‐aramid fibers were evaluated based on scanning electron microscopy, silver weight gain percentage calculation, electrical resistance measurement, crystal structure analysis, and mechanical properties test. The results showed that a higher silver weight gain was advantageous to the improvement of conductivity for the silver‐deposited para‐aramid fibers. The obtained silver deposit was homogenous and compact. Electroless silver‐plating deposits were considered to be three‐dimensional nucleation and growth model (Volmer–Weber). Black, silver gray, and white deposits appeared sequentially with progressive plating. The breaking strength of silver‐deposited para‐aramid fibers remained at value up to 44 N. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Thermal and mechanical properties of chitosan reinforced polyhydroxybutyrate composites
Authors: Rajan Rathish , Sreekumar P. A. , Joseph Kuruvilla , Skrifvars Mikael
Published: November 2011

The article reports the results of studies on the effect of chitosan (0, 5, 10, 20, 30, and 40 wt %) on thermal and mechanical properties of poly(hydroxybutyrate) composites. The addition of chitosan causes an increase in the glass transition temperature (Tg) while a decrease in the enthalpy of fusion (ΔHfus), crystallization (ΔHcry) and percentage of crystallinity as determined by differential scanning calorimeter (DSC). The thermogravimetric analysis reveals that high amount of chitosan decreases the thermal stability of the composites. The Young's modulus of the composite increases and is high for the composite having 40 wt % of chitosan. Increase in the amount of chitosan decreases the elongation at break and impact strength of composites. Finally, the Young's modulus of the composites has been compared with the theoretical predictions. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Evolution of aggregation structure of polyacrylonitrile fibers in the cyclization reaction
Authors: Wang Bin , Xiao Shijie , Cao Weiyu , Shi Xin , Xu Lianghua
Published: November 2011

The aggregation structure of polyacrylonitrile precursor evolves gradually with progress of cyclization. In this work, the variety of cyclization degrees were determined by Fourier transform infrared spectroscopy and the evolution of aggregation structure of PAN fibers were characterized by wide‐angle X‐ray diffraction. Experimental results showed that the cyclization occurred first in the amorphous parts when the heating temperature was below 200°C. After heated at 200°C for 30 min, molecular chains in the pseudo‐crystalline regions started to pack into crystalline regions due to the increasing stress which was produced by cyclization occurred in the amorphous phase, and the crystallinity and crystallite size increased slowly. When the temperature reached to 220°C, pseudo‐crystalline regions rearranged obviously under stress, while molecular chains in the crystalline region started to participate in cyclization, and the original crystalline structures were destructed. The two competitive processes induced that the crystallinity and crystallite size grew to the maximum values at 30 min. When the temperature up to 240°C, the cyclization occurred in the crystalline region became more intensely, while the crystallinity and crystallite size decreased out of synchronize. A scheme of evolution of aggregation structure in cyclization was modified based on the above results. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Rheological characterization of concentrated cellulose solutions in 1‐allyl‐3‐methylimidazolium chloride
Authors: Lu Fei , Cheng Bowen , Song Jun , Liang Yi
Published: November 2011

The rheological properties of high concentrated wood pulp cellulose 1‐allyl‐3‐methy‐limidazolium Chloride ([Amim]Cl) solutions were investigated by using steady shear and dynamic viscoelastic measurement in a large range of concentrations (10–25 wt %). The measurement reveals that cellulose may slightly degrade at 110°C in [Amim]Cl and the Cox–Merz rule is valid for 10 wt % cellulose solution. All of the cellulose solutions showed a shear thinning behavior over the shear rate at temperature from 80 to 120°C. The zero shear viscosity (ηo) was obtained by using the simplified Cross model to fit experimental data. The ηo values were used for detailed viscosity‐concentration and activation energy analysis. The exponent in the viscosity‐concentration power law was found to be 3.63 at 80°C, which is comparable with cellulose dissolved in other solvents, and to be 5.14 at 120°C. The activation energy of the cellulose solution dropped from 70.41 to 30.54 kJ/mol with an increase of concentration from 10 to 25 wt %. The effects of temperature and concentration on the storage modulus (G′), the loss modulus (G″) and the first normal stress difference (N1) were also analyzed in this study. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Proton exchange composite membranes from blends of brominated and sulfonated poly(2,6‐dimethyl‐1,4‐phenylene oxide)
Authors: Xu Tongwen , Wu Dan , Seo Seok‐Jun , Woo Jung‐Je , Wu Liang , Moon Seung‐Hyeon
Published: November 2011

New composite proton exchange membrane was prepared by mixing a 1‐methyl‐2‐pyrrolidone (NMP) solution of sulfonated poly(2,6‐dimethyl‐1,4‐phenylene oxide) (SPPO) in sodium form and brominated poly(2,6‐dimethyl‐1,4‐phenylene oxide) (BPPO) for hydrophilic‐hydrophobic balance, then casting the solution as a thin film, evaporating the solvent, and treating the membrane with aqueous hydrochloric acid. The resulting membranes were subsequently characterized using FTIR‐ATR, SEM‐EDXA, and TGA instrumentation as well as measurements of basic properties such as ion exchange capacity (IEC), water uptake, proton conductivity, methanol permeability, and single cell performance. Water uptake, IEC, proton conductivity, and methanol permeability all increased with a corresponding increase of SPPO content. By properly compromising the conductivity and methanol permeability, membranes with 60–80 wt % SPPO content exhibited comparable proton conductivity to that of Nafion® 117, with only half the methanol permeability, thereby demonstrating higher single cell performance. The membranes developed in this study could thus be a suitable candidate electrolyte for proton exchange membrane fuel cells (PEMFCs). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Comparative study on the exfoliated expanded graphite nanosheet‐PES composites prepared via different compounding method
Authors: Bian J. , Wei X. W. , Lin H. L. , Wang L. , Guan Z. P.
Published: November 2011

Composites made of polyethersulfone (PES) reinforced with exfoliated graphite nanoplatelets are fabricated by melt mixing, polymer solution, and coating. Coating is an efficient compounding method emphasized in this research, where expanded graphite (EG) and PES powder are premixed in isopropyl alcohol using sonication to disperse the EG by coating individual PES powder particles. The microstructure and property of EG/PES composites were investigated by X‐ray diffraction, scanning electron microscope, thermal gravimetric analysis, differential scanning calorimetric, and electronic tensile tester. The electrical conductivity was confirmed using electrochemical tester. It is found that the coating method is more effective than the polymer solution and directly melt mixing methods widely used, in terms of increasing the electrical conductivity and lowering the percolation threshold of thermoplastic composites, and enhancing the probability that the large platelet morphology of EG can be preserved in the final composite. The research reported here provides an understanding on how the compounding method used during the fabrication of composites is important to achieving the optimal mechanical properties, thermal properties, electrical conductivity, and percolation threshold. This method should have wide applicability to all thermoplastic matrix composite systems. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
CDNA cloning and characterization of S6 kinase and its effect on yolk protein gene expression in the oriental fruit fly Bactrocera dorsalis (Hendel)
Authors: Suganya R. , Chen Shiu‐Ling , Lu Kuang‐Hui
Published: November 2011

p70 S6 kinase (S6K), a serine/threonine protein kinase, is a downstream target of target of rapamycin (TOR) gene and an important regulator of protein synthesis responsible for cell growth and reproduction. In this study, a S6K gene, named BdS6K (GenBank Accession No. GQ203802), was isolated from the oriental fruit fly Bactrocera dorsalis (Hendel). Quantitative RT‐PCR showed that BdS6K mRNA is expressed at a higher level in egg than in other developmental stages, as well as in ovary than in fat body. Downregulation of BdS6K activity by rapamycin treatment in larval stage resulted in the developmental defects of larvae, pupae, and adults, with a reduced yolk protein (YP) expression in the fat body throughout the first reproductive cycle with a substantial reduction in ovary size, and also repressed the egg development in female fruit fly. Knockdown of BdS6K gene by RNA interference in the adult significantly decreased the YP expression. These observations support the involvement of BdS6K signaling in the regulation of the YP synthesis and egg development in B. dorsalis. © 2011 Wiley Periodicals, Inc.
Observer‐Based Reliable Control for Discrete‐Time Switched Linear Systems with Faulty Actuators
Authors: Li Jiao , Zhao Jun
Published: November 2011

This paper deals with the issue of reliable control for discrete‐time switched linear systems with faulty actuators by utilizing a multiple Lyapunov functions method and estimate state‐dependent switching technique. A solvability condition for the reliable control problem is given in terms of matrix inequality with an extra matrix variable. This condition allows the reliable control problem for each individual subsystem to be unsolvable. For each subsystem of such a switched system, we design an observer and an observer‐based controller. A switching rule depending on the observer state is designed which, together with the controllers, can guarantee the stability of the closed‐loop switched system for all admissible actuator failures. The observers, controllers, and switching law are explicitly computed by solving linear matrix inequalities (LMIs). The proposed design method is illustrated by two numerical examples.