bluuebunny/crossref_metadata_2025 huggingface dataset:
Operator Differentiable Functions
Authors: Pedersen Gert K.
Published: December 2007

We study the Banach

{}^*

-algebra

C^1_{\mathrm{op}}(I)

of

C^1

-functions on the compact interval

I

such that the corresponding Hilbert space operator function

T → f(T)

, for

T = T^*

and

\mathrm{sp}(T) ⊂ I

, is Fréchet differentiable. If

f(x) = \int e^{itx} \hat f^(t)dt

, we know that the differential is given by the formula

df_T(S) = \int_{-∞}^∞ \int_0^1 U_{st}SU_{(1-s)t} ds\widehat{f'}(t) dt,

where

U_t = \exp(itT)

. Functions of this type are dense in

C^1_{\mathrm{op}}(I)

, and

C^2(I) ⊂ C^1_{\mathrm{op}}(I) ⊂ C^1(I)

, so several classical results can be deduced. In particular we show that if

T \in \mathfrak D(δ)

, where

δ

is the generator of a one-parameter group of

{}^*

-automorphisms of a

C^*

-algebra

\mathfrak A

(or just a closed

{}^*

-derivation in

\mathfrak A

), then

f(T) \in \mathfrak D(δ)

for every

f

in

C^1_{\mathrm{op}}(I)

, where

\mathrm{sp}(T) ⊂ I

, and

δ(f(T)) = df_T(δ(T)).
Possible interactions between environmental factors in determining species optima
Authors: Pakeman R.J. , Reid C.L. , Lennon J.J. , Kent M.
Published: December 2007

Questions: 1. Indicator values, such as those of Ellenberg, for different environmental factors are seen as independent. We tested for the presence of interactions between environmental factors (soil moisture and reaction) to see if this assumption is simplistic. 2. How close are Ellenberg indicator values (IV s) related to the observed optima of species response curves in an area peripheral to those where they have been previously employed and 3. Can the inclusion of bryophytes add to the utility of IVs?

Location: South Uist, Outer Hebrides, Scotland, UK.

Methods: Two grids (ca. 2000 m × 2000 m) were sampled at 50‐m intervals across the transition from machair to upland communities covering an orthogonal gradient of both soil pH (reaction) and soil moisture content. Percentage cover data for vascular plants, bryophytes and lichens were recorded, along with pH and moisture content of the underlying sand/soil/ peat. Reaction optima, derived from species response curves calculated using HOF models, were compared between wet and dry sites, and moisture optima between acidic and basic samples. Optima for the whole data set were compared to Ellenberg IVs to assess their performance in this area, with and without the inclusion of bryophytes.

Results: A number of species showed substantially different pH optima at high and low soil moisture contents (18% of those tested) and different soil moisture optima at high and low pH (49%). For a number of species the IVs were poor predictors of their actual distribution across the sampled area. Bryophytes were poor at explaining local variation in the environmental factors and also their inclusion with vascular plants negatively affected the strength of relationships.

Conclusions: A substantial number of species showed an interaction between soil moisture and reaction in determining their optima on the two respective gradients. It should be borne in mind that IVs such as Ellenberg's may not be independent of one another.
Hydroxyurea chemotherapy in the treatment of meningiomas
Authors: Newton Herbert B.
Published: December 2007

✓ Meningiomas are slow growing, extraaxial tumors that derive from the arachnoidal cap cells of the meninges. Resection remains the main modality of treatment and can be curative in some cases. External-beam radiotherapy and radiosurgery can benefit selected patients. The role of chemotherapy continues to be defined, but should be considered for patients with inoperable or frequently recurring meningiomas. Hydroxyurea, an inhibitor of ribonucleotide reductase, is one of the most active agents and is known to induce apoptosis in meningioma cells in vitro and in mouse xenografts. Results of preliminary clinical studies suggest that hydroxyurea has modest activity against recurrent and inoperable meningiomas, and can induce long term stabilization in some patients. However, the results are conflicting and a few clinical trials did not show positive results. Further clinical trials with larger patient cohorts and longer follow-up periods will be necessary to confirm the activity of hydroxyurea.
Targeted drug therapy for meningiomas
Authors: Norden Andrew D. , Drappatz Jan , Wen Patrick Y.
Published: December 2007

✓ Although advances in surgery, radiation therapy, and stereotactic radiosurgery have significantly improved the treatment of meningiomas, there remains an important subset of patients whose tumors are refractory to conventional therapy. Treatment with traditional chemotherapeutic agents has provided minimal benefit. In this review, the role of targeted molecular therapies for recurrent or progressive meningiomas is discussed.
Primary intraosseous meningioma
Authors: Elder James B. , Atkinson Roscoe , Zee Chi-Shing , Chen Thomas C.
Published: December 2007

✓Primary intraosseous meningiomas are a subtype of primary extradural meningiomas and constitute fewer than 2% of meningiomas overall, but they represent approximately two thirds of all extradural meningiomas. These types of meningiomas originate within the bones of the skull and thus can have a clinical presentation and radiographic differential diagnosis that is different from those for intradural meningiomas.

Primary intraosseous meningiomas are classified based on their location and histopathological characteristics. Treatment primarily involves resection with wide margins if possible. Very little literature exists regarding the use of adjuvant therapies such as radiation and chemotherapy for these tumors. In fact, the literature regarding primary intra-osseous meningiomas consists mostly of clinical case reports and case series. This literature is reviewed and summarized in this article.
Management of spinal meningiomas: surgical results and a review of the literature
Authors: Setzer Matthias , Vatter Hartmut , Marquardt Gerhard , Seifert Volker , Vrionis Frank D.
Published: December 2007

Object

In this report, the authors describe their experience in the surgical management of spinal meningiomas at two neurosurgical centers. The results of a literature review are also presented.

Methods

Eighty consecutive patients (22 men and 58 women) with spinal meningiomas who had undergone an operation at two specific neurosurgical centers were included in this study. Functional outcomes were evaluated using univariate and multivariate analyses. A review of the literature yielded an additional 651 patients with spinal meningiomas from 9 large studies.

Results

On multivariate analysis, the variable of a poor preoperative neurological state (p < 0.02, odds ratio [OR] 13.6, 95% confidence interval [CI] 2.6–71.4) and invasion of the arachnoid/pia mater (p < 0.03, OR 15.2, 95% CI 2.5–90.4) were independent predictors of a poor outcome, whereas invasion of the arachnoid/pia (p < 0.02, OR 8.9, 95% CI 2.2–35) and duration of symptoms (p < 0.001, OR 1.12/month, 95% CI 1.05–1.2) predicted no improvement (stable or deteriorated condition). The Cox proportional hazards regression analysis showed three significant predictor variables for recurrence: invasion of the arachnoid/pia (p < 0.05; hazard ratio [HR] 1.8, 95% CI 1.2–3.6), Simpson resection grade (p < 0.012, HR 6.8, 95% CI 1.5–3.0), and histological tumor grade (Grade I; p < 0.001, HR 0.001–0.17).

Conclusions

Because of the excellent outcome of surgery for benign spinal meningiomas and the association between duration of symptoms and neurological compromise with a poor functional outcome, early operation is the treatment of choice. In cases of malignant transformation, adjuvant therapies must be considered.
Meningiomas: causes and risk factors
Authors: Barnholtz-Sloan Jill S. , Kruchko Carol
Published: December 2007

✓ Meningiomas are among the most common primary intracranial tumors. Although the vast majority of these tumors are considered histologically benign, the incidence of complications can be high. Few studies have investigated the causes and risk factors for meningioma; this review highlights the current state of knowledge. Gaining a better understanding of the origin of this disease is essential so that treatments and outcomes can be improved and prevention strategies can be developed.
Stereotactic radiation treatment for benign meningiomas
Authors: Elia Andrew E. H. , Shih Helen A. , Loeffler Jay S.
Published: December 2007

✓Meningiomas are the second most common primary tumor of the brain. Gross-total resection remains the preferred treatment if achievable with minimal morbidity. For incompletely resected or inoperable benign meningiomas, 3D conformal external-beam radiation therapy can provide durable local tumor control in 90 to 95% of cases. Stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (SRT) are highly conformal techniques, using steep dose gradients and stereotactic patient immobilization. Stereotactic radiosurgery has been used as an alternative or adjuvant therapy to surgery for meningiomas in locations, such as the skull base, where operative manipulation may be particularly difficult. Stereotactic radiotherapy is useful for larger meningiomas (> 3–3.5 cm) and those closely approximating critical structures, such as the optic chiasm and brainstem. Although SRS has longer follow-up than SRT, both techniques have excellent 5-year tumor control rates of greater than 90% for benign meningiomas. Stereotactic radiotherapy has toxicity equivalent to that of radiosurgery, despite its biased use for larger meningiomas with more complicated volumes. Reported rates of imaging-documented regression are higher for radiosurgery, but neurological recovery is relatively good with both techniques. Stereotactic radiosurgery and fractionated SRT are complementary techniques appropriate for different clinical scenarios.
Inflammatory response and meningioma tumorigenesis and the effect of cyclooxygenase-2 inhibitors
Authors: Ragel Brian T. , Jensen Randy L. , Couldwell William T.
Published: December 2007

✓In this article the authors discuss the rationale and research supporting the hypothesis that meningioma tumorigenesis may, in part, be driven by overexpression of cyclooxygenase-2 (Cox-2) and that treatment with celecoxib, a selective Cox-2 inhibitor, may hold therapeutic promise. Because therapies for recurrent or aggressive meningiomas (atypical or malignant subtypes) such as chemotherapy and radiotherapy generally offer little therapeutic benefit, interest in targeting Cox-2 has grown. This rate-limiting enzyme of prostaglandin synthesis can be inhibited with nonsteroidal antiinflammatory drugs (NSAIDs) such as ibuprofen and celecoxib. Treatment with NSAIDs has been shown to curb the tumorigenic properties of prostaglandins in several cancer models via both Cox-2-dependent and -independent mechanisms. In addition, celecoxib is well tolerated in humans, making its use as a chronic therapy for meningiomas attractive.
Are there attacking points in the eicosanoid cascade for chemotherapeutic options in benign meningiomas?
Authors: Pfister Christina , Ritz Rainer , Pfrommer Heike , Bornemann Antje , Tatagiba Marcos S. , Roser Florian
Published: December 2007

Object

The current treatment for recurrent or malignant meningiomas with adjuvant therapies has not been satisfactory, and there is an intense interest in evaluating new molecular markers to act as therapeutic targets. Enzymes of the arachidonic acid (AA) cascade such as cyclooxygenase (COX)–2 or 5-lipoxygenase (5-LO) are upregulated in a number of epithelial tumors, but to date there are hardly any data about the expression of these markers in meningiomas. To find possible targets for chemotherapeutic intervention, the authors evaluated the expression of AA derivatives at different molecular levels in meningiomas.

Methods

One hundred and twenty-four meningioma surgical specimens and normal human cortical tissue samples were immunohistochemically and cytochemically stained for COX-2, COX-1, 5-LO, and prostaglandin E receptor 4 (PTGER4). In addition, Western blot and polymerase chain reaction (PCR) analyses were performed to detect the presence of eicosanoids in vivo and in vitro.

Results

Sixty (63%) of 95 benign meningiomas, 21 (88%) of 24 atypical meningiomas, all five malignant meningiomas, and all normal human cortex samples displayed high COX-2 immunoreactivity. All cultured specimens and IOMM-Lee cells stained positive for COX-2, COX-1, 5-LO, and PTGER4. The PCR analysis demonstrated no changes in eicosanoid expression among meningiomas of different World Health Organization grades and in normal human cortical and dura mater tissue.

Conclusions

Eicosanoid derivatives COX-1, COX-2, 5-LO, and PTGER4 enzymes show a high universal expression in meningiomas but are not upregulated in normal human cortex and dura tissue. This finding of the ubiquitous presence of these enzymes in meningiomas offers an excellent baseline for testing upcoming chemotherapeutic treatments.
Multisession CyberKnife radiosurgery for optic nerve sheath meningiomas
Authors: Romanelli Pantaleo , Wowra Berndt , Muacevic Alexander
Published: December 2007

✓ Optic nerve sheath meningiomas (ONSMs) are benign lesions originating from the dural sheath of the optic nerve. Progressive growth can lead to gradual loss of vision and exophthalmos. Loss of vision following microsurgical resection is not uncommon, and although stereotactic fractionated radiotherapy can be a safe alternative to control tumor growth and preserve vision, it may also lead to complications. Frame-based stereotactic radiosurgery has only been rarely used because single-fraction high-dose treatments of intrinsic optic nerve lesions may induce unacceptably high toxicity. New frameless radiosurgery devices such as the robotic CyberKnife, an image-guided radiosurgery system, can provide the extremely tight conformality and submillimetric accuracy of frame-based systems combined with the possibility of delivering radiation in several sessions. In the present report the authors review the clinical presentation and management of ONSMs and describe their preliminary experience using multisession radiosurgery to treat these lesions.
Role of Gamma Knife surgery in the management of pineal region tumors
Authors: Lekovic Gregory P. , Gonzalez L. Fernando , Shetter Andrew G. , Porter Randall W. , Smith Kris A. , Brachman David , Spetzler Robert F.
Published: December 2007

Object

Increasingly, radiosurgery is used to treat pineal region tumors, either as a primary treatment or as an adjunct to conventional radiation therapy. The authors report their experience with Gamma Knife surgery (GKS) for the treatment of pineal region tumors.

Methods

The authors retrospectively reviewed the charts of all patients undergoing GKS at their institution between 1997 and 2005. Seventeen patients underwent GKS for nonmetastatic tumors of the pineal region. All patients were treated using Leksell Gamma Plan treatment planning software (versions 4.12::5.34). The mean treatment volume was 7.42 cm3 (range 1.2–32.5 cm3). Prescribed doses ranged from 12 to 18 Gy. All doses were prescribed to the 50% isodose line. Independent neuroradiologists reviewed all follow-up imaging studies for evidence of progression of disease.

Results

One patient (Case 10) died 6 days after GKS. Mean clinical and imaging follow-up in the remaining 16 cases was 31 months. Local control was established during a mean neuroimaging follow-up period of 31 months (range 1–95) in 16 patients (100%). In 2 of these 16 patients (one with an anaplastic astrocytoma, the other with a primitive neuroectodermal tumor), leptomeningeal and spinal spread of tumor developed despite control of the pineal lesions. There were no new neurological deficits attributable to GKS. Three patients died (including the one who died 6 days after GKS) during the follow-up period.

Conclusions

Excellent control of pineal region brain tumors can be obtained with GKS when it is used in conjunction with surgery, conventional radiation therapy, or both. Patient survival and quality of life can be optimized through the use of multimodal treatment, including surgery, conventional radiation therapy and/or radiosurgery, and chemotherapy, when applicable.
Irradiation of glomus jugulare tumors: a historical perspective
Authors: Li Gordon , Chang Steven , Adler John R. , Lim Michael
Published: December 2007

✓ Glomus jugulare tumors are rare, slow-growing vascular lesions that arise from the chief cells of the paraganglia within the jugular bulb. They can be associated with the tympanic branch of the glossopharyngeal nerve (Jacobsen nerve) or the auricular branch of the vagus nerve (Arnold nerve) and are also referred to as chemodectomas or nonchromaffin paragangliomas. Optimal treatment of these histologically benign tumors remains controversial. Surgery remains the treatment of choice, but can carry high morbidity rates. External-beam radiation was originally used for subtotal resections and in patients who were poor surgical candidates; however, radiosurgery has recently been introduced as an effective and safe treatment option for patients with these tumors. In this article the authors discuss the history of radiation therapy for glomus jugulare tumors, focusing on recent radiosurgical results.
Stereotactic radiosurgery for Cushing disease: a review
Authors: Oyesiku Nelson M.
Published: December 2007

✓ A contemporary review of the use of stereotactic radiosurgery in the treatment of Cushing disease (CD) is presented with information drawn from a literature review and from the author's experience. Stereotactic radiosurgery is an effective and safe therapeutic alternative for treating CD in carefully selected cases. Improvements in imaging, dose planning, and general understanding of radiobiology are likely to yield better results in the future.
Stereotactic radiosurgery for functional disorders
Authors: Friehs Gerhard M. , Park Michael C. , Goldman Marc A. , Zerris Vasilios A. , Norén Georg , Sampath Prakash
Published: December 2007

✓ Stereotactic radiosurgery (SRS) with the Gamma Knife and linear accelerator has revolutionized neurosurgery over the past 20 years. The most common indications for radiosurgery today are tumors and arteriovenous malformations of the brain. Functional indications such as treatment of movement disorders or intractable pain only contribute a small percentage of treated patients. Although SRS is the only noninvasive form of treatment for functional disorders, it also has some limitations: neurophysiological confirmation of the target structure is not possible, and one therefore must rely exclusively on anatomical targeting. Furthermore, lesion sizes may vary, and shielding adjacent radiosensitive neural structures may be difficult or impossible.

The most common indication for functional SRS is the treatment of trigeminal neuralgia. Radiosurgical treatment for epilepsy and certain psychiatric illnesses is performed in several centers as part of strict research protocols, and radiosurgical pallidotomy or medial thalamotomy is no longer recommended due to the high risk of complications. Radiosurgical ventrolateral thalamotomy for the treatment of tremor in patients with Parkinson disease or multiple sclerosis, as well as in the treatment of essential tremor, may be indicated for a select group of patients with advanced age, significant medical conditions that preclude treatment with open surgery, or patients who must receive anticoagulation therapy. A promising new application of SRS is high-dose radiosurgery delivered to the pituitary stalk. This treatment has already been successfully performed in several centers around the world to treat severe pain in patients with end-stage cancer.
Contemporary methods of radiosurgery treatment with the Novalis linear accelerator system
Authors: Chen Joseph C. T. , Rahimian Javad , Girvigian Michael R. , Miller Michael J.
Published: December 2007

✓ Radiosurgery has emerged as an indispensable component of the multidisciplinary approach to neoplastic, functional, and vascular diseases of the central nervous system. In recent years, a number of newly developed integrated systems have been introduced for radiosurgery and fractionated stereotactic radiotherapy treatments. These modern systems extend the flexibility of radiosurgical treatment in allowing the use of frameless image-guided radiation delivery as well as high-precision fractionated treatments. The Novalis linear accelerator system demonstrates adequate precision and reliability for cranial and extracranial radiosurgery, including functional treatments utilizing either frame-based or frameless image-guided methods.
Advances in the radiosurgical treatment of large inoperable arteriovenous malformations
Authors: Jones Jesse , Jang Sunyoung , Getch Christopher C. , Kepka Alan G. , Marymont Maryanne H.
Published: December 2007

✓ Radiosurgery has proven useful in the treatment of small arteriovenous malformations (AVMs) of the brain. However, the volume of healthy tissue irradiated around large lesions is rather significant, necessitating reduced radiation doses to avoid complications. As a consequence, this can produce poorer obliteration rates. Several strategies have been developed in the past decade to circumvent dose–volume problems with large AVMs, including repeated treatments as well as dose, and volume fractionation schemes. Although success on par with that achieved in lesions smaller than 3 ml remains elusive, improvements over the obliteration rate, the complication rate or both have been reported after conventional single-dose stereotactic radiosurgery (SRS). Radiosurgery with a marginal dose or peripheral dose < 15 Gy rarely obliterates AVMs, yet most lesions diminish in size posttreatment. Higher doses may then be reapplied to any residual nidi after an appropriate follow-up period. Volume fractionation divides AVMs into smaller segments to be treated on separate occasions. Doses > 15 Gy irradiate target volumes of only 5–15 ml, thereby minimizing the radiation delivered to the surrounding brain tissue. Fewer adverse radiological effects with the use of fractionated radiosurgery over standard radiosurgery have been reported. Advances in AVM localization, dose delivery, and dosimetry have revived interest in hypofractionated SRS. Investigators dispensing ≥ 7 Gy per fraction minimum doses have achieved occlusion with an acceptable number of complications in 53–70% of patients. The extended latency period between treatment and occlusion, about 5 years for emerging techniques (such as salvage, staged volume, and hypofractionated radiotherapy), exposes the patient to the risk of hemorrhage during that period. Nevertheless, improvements in dose planning and target delineation will continue to improve the prognosis in patients harboring inoperable AVMs.
CyberKnife radiosurgical rhizotomy for the treatment of atypical trigeminal nerve pain
Authors: Patil Chirag G. , Veeravagu Anand , Bower Regina S. , Li Gordon , Chang Steven D. , Lim Michael , Adler John R.
Published: December 2007

Object

Patients with atypical trigeminal neuralgia (TN) have unilateral pain in the trigeminal distribution that is dull, aching, or burning in nature and is constant or nearly constant. Studies of most radiosurgical and surgical series have shown lower response rates in patients with atypical TN. This study represents the first report of the treatment of atypical TN with frameless CyberKnife stereotactic radiosurgery (SRS).

Methods

Between 2002 and 2007, 7 patients that satisfied the criteria for atypical TN and underwent SRS were included in our study. A 6–8-mm segment of the trigeminal nerve was targeted, excluding the proximal 3 mm at the brainstem. All patients were treated in a single session with a median maximum dose of 78 Gy and a median marginal dose of 64 Gy.

Results

Outcomes in 7 patients with a mean age of 61.6 years and a median follow-up of 20 months are reported. Following SRS, 4 patients had complete pain relief, 2 had minimal pain relief with some decrease in the intensity of their pain, and 1 patient experienced no pain relief. Pain relief was reported within 1 week of SRS in 4 patients and at 4 months in 2 patients. After a median follow-up of 28 months, pain did not recur in any of the 4 patients who had reported complete pain relief. Complications after SRS included bothersome numbness in 3 patients and significant dysesthesias in 1 patient.

Conclusions

The authors have previously reported a 90% rate of excellent pain relief in patients with classic TN treated with CyberKnife SRS. Compared with patients with classic TN, patients with atypical TN have a lower rate of pain relief. Nevertheless, the nearly 60% rate of success after SRS achieved in this study is still comparable to or better than results achieved with any other treatment modality for atypical TN.
BTXProcessing
Authors: Sweeney W. A. , Bryan P. F.
Published: December 2007

Benzene (B), toluene (T), and the xylenes (X) are the lowest weight hydrocarbon analogues. They are each very large‐scale chemical feedstocks. Since they are often produced in the same process, they can be considered a group, ie, BTX. However, BTX is not an article of commerce. It is either an important component of a crude mixture such as reformate or pyrolysis gasoline or it is separated into its individual components. This article mainly discusses the processes for making these crude mixtures: Originally BTX was obtained commercially by the pyrolysis of coal. It is now closely connected with the production of gasoline. BTX comprises an important gasoline component called reformate. Any BTX chemical needed is separated from the reformate stream before it is blended in the gasoline pool. Details on the reforming process, hydrolysis pyrolysis, BTX from light hydrocarbons, and other processes are given. The complexity of separating the components from the crude materials depends on the amount of nonaromatic compounds present. Separation and purification are performed by extraction, extractive distillation, and absorption. In addition, downstream operations are also carried out. BTX chemicals are hazardous and environmental pressures are increasing to reduce emissions and workplace exposure. A very wide range of chemicals from solvents, to fibers, films and plastics are prepared from the BTX chemicals.
Supported Ionic Liquid Enzymatic Catalysis for the Production of Biodiesel
Authors: Gamba Muriell , Lapis Alexandre A. M. , Dupont Jairton
Published: December 2007

Pseudomonas cepacia lipase supported in the 1‐n‐butyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquid is an alternative “green” method for the production of biodiesel from the alcoholysis of soybean oil. The transesterification reaction catalyzed by this ionic liquid‐supported enzyme can be performed at room temperature, in the presence of water and without the use of organic solvents. It is also compatible with various alcohols (including isoamyl alcohol). The biodiesel is separated by simple decantation and the recovered ionic liquid/enzyme catalytic system can be re‐used at least four times without loss of catalytic activity and selectivity.
Fluorogenic Transformations Based on Formation of CC Bonds Catalyzed by Palladium: An Efficient Approach for High Throughput Optimizations and Kinetic Studies
Authors: Rozhkov Roman V. , Davisson V. Jo , Bergstrom Donald E.
Published: December 2007

We have developed novel fluorogenic transformations based on formation of CC bonds catalyzed by palladium using iodocoumarin 1 as a model aryl iodide, where fluorescence is quenched completely due to effects of the heavy, polarizable iodine atom. Substitution of the iodine atom for the carbon using Sonogashira, Suzuki–Miyaura and Heck couplings results in a dramatic fluorescence enhancement. This approach has been used successfully for the optimization of reaction conditions and kinetic studies in high throughput format.
Reaction of 3‐(1‐Arylsulfonylalkyl)‐indoles with Easily Enolisable Derivatives Promoted by Potassium Fluoride on Basic Alumina
Authors: Ballini Roberto , Palmieri Alessandro , Petrini Marino , Shaikh Rafik R.
Published: December 2007

Active methylene compounds and nitro derivatives react with 3‐(1‐arylsulfonylalkyl)‐indoles in the presence of potassium fluoride on basic alumina at room temperature leading to the corresponding adducts in good yields. Under basic conditions, sulfonylindoles suffer elimination of arenesulfinic acid leading to an intermediate vinylogous imine that promptly adds stabilized carbanions. The obtained 3‐indolyl derivatives are pivotal intermediates for the synthesis of indole‐based alkaloids and amino acids.
Homogeneous Hydrogenation of Tri‐ and Tetrasubstituted Olefins: Comparison of Iridium‐Phospinooxazoline [Ir‐PHOX] Complexes and Crabtree Catalysts with Hexafluorophosphate (PF6) and Tetrakis[3,5‐bis(trifluoromethyl)phenyl]borate (BArF) as Counterions
Authors: Wüstenberg Bettina , Pfaltz Andreas
Published: December 2007

Four iridium complexes with achiral phosphino‐oxazoline (PHOX) ligands were readily prepared in two steps starting from commercially available phenyloxazolines. The air‐stable complexes with tetrakis[3,5‐bis(trifluoromethyl)phenyl]borate (BArF) as counterion showed high reactivity in the hydrogenation of a range of tri‐ and tetrasubstituted olefins. The best results were obtained with an iridium complex (11) derived from a dicyclohexylphosphino‐oxazoline ligand bearing no additional substituents in the oxazoline ring. With several substrates, which gave only low conversion with the Crabtree catalyst, [Ir(Py)(PCy3)(COD)]PF6, full conversion was observed. The productivity of the Crabtree catalyst could be strongly increased by replacing the hexafluorophosphate anion with tetrakis[3,5‐bis(trifluoromethyl)phenyl]borate. In one case, in the hydrogenation of a tetraalkyl‐substituted CC bond, [Ir(Py)(PCy3)(COD)]BArF gave higher conversion than catalyst 11. However, with several other substrates complex 11 proved to be superior.
Genetic screening for reproductive purposes at school: Is it a good strategy?
Authors: Frumkin Ayala , Zlotogora Joël
Published: December 2007

Thalassemia and Tay‐Sachs disease were the first diseases in which the criteria for heterozygote genetic screening were met and successful programs for reproductive purposes were initiated in populations at risk. However, many of the couples first discover the possibility of genetic screening during pregnancy and efforts are made to bring couples to consider screening tests before the first pregnancy. In this context, high school offers a convenient setting and several pilot programs have been very successful. All evaluations of these programs found that education plays a critical role in allowing informed decisions and minimizing the possible harms. While it has been suggested that high school may be the best setting for reproductive screening programs, guidelines of several societies of human genetics recommend the use of carrier screening only in individuals older than 18 years. There are several other problems related to genetic screening programs at school and some are discussed in the review. Our opinion is that school should be a place to provide the tools for decisions by education only; while the option to have the genetic tests later in life or in another setting should be offered to the students as part of the education session. This may allow the students to decide when and where to have a genetic test. © 2007 Wiley‐Liss, Inc.
Noonan syndrome: Psychological and psychiatric aspects
Authors: Verhoeven Willem , Wingbermühle Ellen , Egger Jos , Van der Burgt Ineke , Tuinier Siegfried
Published: December 2007

Although Noonan syndrome (NS) is a disorder with a relatively high prevalence, virtually no information in adult patients is available about the psychological and psychopathological profile. In the present clinical report the first series of 10 NS patients from an ongoing project is presented. The purpose of the study is to investigate the psychopathology, social cognition and adaptation as well as the quality of life in NS patients aged 16 years or more. PTPN11 mutations were present in six patients and KRAS and SOS1 in one patient, respectively. In two patients no known mutation was found. The results demonstrate a variable level of intelligence and suggest moderately impaired social cognition in terms of emotion recognition and alexithymia. In some patients mild signs of anxiety and lowered mood are found that, however, do not meet the criteria for a specific psychiatric disorder. It is concluded that NS in adults is associated with a behavioral phenotype in which deficiencies in social and emotional recognition and expression may be key elements. © 2007 Wiley‐Liss, Inc.
Heritability of obsessive‐compulsive symptom dimensions
Authors: van Grootheest Daniël S. , Boomsma Dorret I. , Hettema John M. , Kendler Kenneth S.
Published: December 2007

Recent research has shown that obsessive‐compulsive symptoms (OCS) differ remarkably among patients and can be divided into several symptom dimensions. OCS are influenced by genetic components, but it is unknown to what extent these symptom dimensions are heritable. The phenotypic heterogeneity also raises the question to what extent the symptom dimensions are influenced by specific or shared genetic factors. We studied a population sample of 1,383 female twins from the Virginia Twin Registry. OCS was measured by a questionnaire with 20 items from the Padua Inventory. After factor analysis, three reliable OC symptom dimensions were retained: Rumination, Contamination, and Checking. These OC dimensions were analyzed with multivariate genetic models to investigate both the overlap and uniqueness of genetic and environmental contributions underlying OC symptom dimensions. The multivariate common pathway model provided the best description of the data. All symptom dimensions share variation with a latent common factor, that is, OC behavior. Variation in this common factor was explained by both genes (36%) and environmental factors (64%). Only the Contamination dimension was influenced by specific genes and seemed to be a relatively independent dimension. The results suggest that a broad OC behavioral phenotype exists, influenced by both genes and nonshared environment. In addition, we found evidence for specific genetic and environmental factors underlying the Contamination dimension. Use of the Contamination dimension could therefore provide a powerful approach for the detection of genetic susceptibility loci that contribute to OCS. © 2007 Wiley‐Liss, Inc.
The −1021 C/T DBH polymorphism is associated with neuropsychological performance among children and adolescents with ADHD
Authors: Kieling Christian , Genro Júlia P. , Hutz Mara H. , Rohde Luis Augusto
Published: December 2007

Catecholaminergic imbalance has increasingly been implicated in the pathophysiology of attention‐deficit/hyperactivity disorder (ADHD). The enzyme dopamine‐β‐hydroxylase (DβH)—critical to catecholaminergic regulation—is under strong genetic control, with the −1021 C/T polymorphism accounting for up to 50% of the enzymatic activity. This work aimed to investigate association between this functional polymorphism and the performance of children and adolescents with ADHD in neuropsychological measures of executive function (EF). Sixty‐four drug‐naïve patients with ADHD undertook a Continuous Performance Test and the Wisconsin Card Sorting Test. By means of a factorial analysis, a composite measure of EF was extracted. Performance according to genotypic group was analyzed, including age as a confounder. In addition, a family‐based association test was conducted as a confirmatory analysis. Principal components analysis of neuropsychological measures loaded two factors that explained 83.8% of total variance. Cognitive performance, as measured by the composite score, showed significant difference between genotypic groups after adjustment for age (P = 0.002). The CC homozygosity was associated with a diminished global EF performance, a result that was corroborated by the intra‐familial analysis. The present study demonstrated an association between the neuropsychological performance of children with ADHD and a functional polymorphism in the promoter region of the DBH gene. The refinement of the ADHD phenotype by means of composite measures of EF can contribute to uncover the molecular underpinnings of ADHD. © 2007 Wiley‐Liss, Inc.
Evidence for association between genetic variants of p75 neurotrophin receptor (p75NTR) gene and antidepressant treatment response in chinese major depressive disorder
Authors: Gau Yung‐Tian A. , Liou Ying‐Jay , Yu Younger W.‐Y. , Chen Tai‐Jui , Lin Ming‐Wei , Tsai Shih‐Jen , Hong Chen‐Jee
Published: December 2007

The p75 neurotrophin receptor (p75NTR) is an essential component of neurotrophin system, and has been implicated in the pathogenesis of major depressive disorder (MDD) and in the mechanism of antidepressant action. This study aimed to delineate the association between phenotype (MDD susceptibility and antidepressant response) and genotype (p75NTR common genetic variants) in a Chinese population. A total of 228 MDD patients and 402 unrelated controls were recruited. Subjects took selective serotonin reuptake inhibitors (SSRIs) and responders were defined as those with at least a 50% decrease in score of the Hamilton Rating Scale for Depression (HAM‐D) from baseline. Five p75NTR polymorphisms were genotyped and their association with MDD or treatment response was assessed by haplotype and single marker analysis. No significant association with MDD was discovered in single locus or haplotype analyses. With regard to the therapeutic outcome, however, one missense polymorphism (S250L) showed association in both genotype distribution (P = 0.039) and allele frequency (P = 0.012). Haplotype analysis also revealed that p75NTR TCT carriers had a more unfavorable response to therapy (P = 0.010). Our exploratory study has demonstrated the association between p75NTR and SSRI response for the first time, which may assist in individualized therapy for MDD patients in the future. © 2007 Wiley‐Liss, Inc.
No association of genetic variants of liver X receptor‐β with alzheimer's disease risk
Authors: Rodríguez‐Rodríguez Eloy , Llorca Javier , Mateo Ignacio , Infante Jon , Sánchez‐Quintana Coro , García‐Gorostiaga Inés , Fernández‐Viadero Carlos , Peña Nicolás , Berciano José , Combarros Onofre
Published: December 2007

Apolipoprotein E (APOE) ε4 allele is the strongest hitherto known risk factor for sporadic Alzheimer's disease (AD). Liver X receptor‐β (LXRβ) is a transcription factor that controls expression of genes involved in brain cholesterol metabolism, and one of the main LXRβ targets is APOE. To evaluate the relationship between LXRβ genetic variants and AD, independently or in concert with the APOE ε4 allele, we examined three LXRβ polymorphisms located in introns 2 (rs 2695121), 5 (rs 1052533), and 7 (rs 1405655), in 414 Spanish AD patients and 447 controls. The current study does not demonstrate an association between LXRβ genotypes or haplotypes and AD, neither in the total sample nor when the populations were stratified for the presence or absence of the APOE ε4 allele. © 2007 Wiley‐Liss, Inc.
Hand preference during unimanual and bimanual reaching actions in Sichuan snub‐nosed monkeys (Rhinopithecus roxellana)
Authors: Zhao Da‐Peng , Ji Wei‐Hong , Watanabe Kunio , Li Bao‐Guo
Published: December 2007

Hand preferences were investigated during one unimanual action (food‐reaching) and one bimanual action (mount‐reaching) in a semi‐free‐ranging group of Sichuan snub‐nosed monkeys (Rhinopithecus roxellana) in Zhouzhi National Nature Reserve, Qinling Mountains of China. Nine of 14 individuals tested on the unimanual food‐reaching action and all six individuals tested on the bimanual mount‐reaching action exhibited a manual preference. Both significant right‐ and left‐handed preferences were observed in the two actions. Sex did not affect either direction or strength of hand preference in the unimanual action. Hand preference for the bimanual action was stable over time, and the strength of hand preference was significantly stronger in the bimanual action than in the unimanual action. Am. J. Primatol. 70:500–504, 2008. © 2007 Wiley‐Liss, Inc.
Supramolecular Assemblies Based on Organometallic Quinonoid Linkers: A New Class of Coordination Networks
Authors: Moussa Jamal , Amouri Hani
Published: December 2007

Self‐assembly of coordination frameworks exhibiting original architectures is an active area of research. Generally, such assemblies are constructed from organic spacers and transition metals of different geometrical structures. Herein, we report a novel class of supramolecular coordination assemblies with organometallic linkers based on metalated quinonoid and thioquinonoid complexes that serve as spacers. The organometallic ligands are stable and have the general formula [Cp*M(η4‐benzoquinone)] (o‐ and p‐benzoquinone, Cp*=C5Me5, M=Rh, Ir) and [Cp*Ir(η4‐thiobenzoquinone)] (o‐ and p‐thiobenzoquinone). These units bind through both oxygen or sulfur atoms to metal ions of different coordination geometry, such as CuI, AgI, and PtII, to generate supramolecular coordination networks, with the metalated quinonoid or thioquinonoid linkers acting as backbones and the metal centers as nodes. This novel family of supramolecular assemblies exhibits short π–π and M⋅⋅⋅M interactions. These results illustrate successfully the role of the organometallic linkers to produce an impressive range of novel supramolecular architectures that hold promise for the development of functional materials.
Towards the Optimal Screening Collection: A Synthesis Strategy
Authors: Nielsen Thomas E. , Schreiber Stuart L.
Published: December 2007

The development of effective small‐molecule probes and drugs entails at least three stages: 1) a discovery phase, often requiring the synthesis and screening of candidate compounds, 2) an optimization phase, requiring the synthesis and analysis of structural variants, 3) and a manufacturing phase, requiring the efficient, large‐scale synthesis of the optimized probe or drug. Specialized project groups tend to undertake the individual activities without prior coordination; for example, contracted (outsourced) chemists may perform the first activity while in‐house medicinal and process chemists perform the second and third development stages, respectively. The coordinated planning of these activities in advance of the first small‐molecule screen tends not to be undertaken, and each project group can encounter a bottleneck that could, in principle, have been avoided with advance planning. Therefore, a challenge for synthetic chemistry is to develop a new kind of chemistry that yields a screening collection comprising small molecules that increase the probability of success in all three phases. Although this transformative chemistry remains elusive, progress is being made. Herein, we review a newly emerging strategy in diversity‐oriented small‐molecule synthesis that may have the potential to achieve these challenging goals.
Low‐temperature curing of water‐dispersible cationic diisocyanates for cathodic electrodeposition coatings
Authors: Wang Tao , Qi Shengguang , Ren Biye , Tong Zhen
Published: December 2007

Water‐dispersible cationically modified diisocyanates TIb and TId blocked by n‐butanol (BAO) and 3,5‐dimethylpyrazole (DMP) for cathode electrodepositing (CED) coating curing were synthesized by introducing cationic triethanolamine (TEOA) into isophorone diisocyanate (IPDI). The crosslinkers TIb and TId were characterized with FTIR, gel permeation chromatography, dynamic light scattering for size distribution, differential scanning calorimeter, and thermogravimetry techniques. The emulsion for CED coating made of TIb or TId and cationic acrylic copolymer showed a high stability with narrow particle diameter distribution because of the ionization of the crosslinker. TG and DSC indicated that the deblocking and crosslinking temperatures of TId and TId containing CED film were always lower than the corresponding temperatures of the TIb and TIb containing CED film. With 0.5 wt % of catalyst dibutyltin dilaurate (DBTL) in TId‐CED emulsion and cured at 140°C for 40 min, 90% of the gel content in the TId‐CED film was realized. Hence, TId can meet the requirement of low‐temperature curing for the CED coating. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Hochwasserschutzdeiche – aktuelle Entwicklungen zur Verbesserung der Hochwassersicherheit
Authors: Bieberstein Andreas , Zesch Rainer , Riegger Tobias , Saucke Ulrich , Scheuermann Alexander , Triantafyllidis Theodor
Published: December 2007

Zum Schutz des Hinterlandes gegen Überflutung bei Hochwasser wurden über Jahrhunderte Deiche entlang von Fließgewässern errichtet, die auch heute noch über weite Strecken im Bestand erhalten sind. Da ein maßgebender Anteil dieser Altdeichstrecken in Deutschland den zwischenzeitlich vorliegenden Erkenntnissen und den Anforderungen der Regelwerke nicht entspricht, sind diese insbesondere bei Hochwasserereignissen mit geringer Auftretenswahrscheinlichkeit bzw. lang anhaltendem Einstau häufig nicht in der Lage, den resultierenden Belastungen schadensfrei zu widerstehen. Somit ergeben sich in Hinsicht auf die Sicherstellung des erforderlichen Hochwasserschutzes bzw. der Hochwassersicherheit aus geotechnischer bzw. geohydraulischer Sicht zahlreiche Fragestellungen, die gegenwärtig am Institut für Bodenmechanik und Felsmechanik der Universität Karlsruhe (TH) im Rahmen verschiedener (Verbund‐)Forschungsvorhaben bearbeitet werden. In diesem Beitrag werden verschiedene aktuelle Entwicklungsvorhaben vorgestellt und erläutert, die mit dem Ziel der Bewertung, der Prognose und der Verbesserung der Standsicherheit von Altdeichen durchgeführt werden.
Ein Approximationsverfahren zur rechnerischen Bestimmung des Hydroabrasionsverschleißes an überströmten Betonoberflächen
Authors: Helbig Ulf , Horlacher Hans‐B.
Published: December 2007

Eine Berechnung des Oberflächenabriebs an angeströmten Betonoberflächen im Wasserbau wird bisher in der Regel nicht vorgenommen. Dabei ist bekannt, dass an Bauwerken des konstruktiven Wasserbaus oder auch des Siedlungswasserbaus regelmäßig Schäden durch Oberflächenverschleiß beobachtet und dokumentiert werden. Das im Folgenden beschriebene Verfahren erlaubt auf der Basis der von Bania [1] gefundenen Zusammenhänge eine Abschätzung der Oberflächenabtrags von neuem Beton in Abhängigkeit der vorhandenen Druckfestigkeit sowie der Abrasionsbeanspruchungszeit und der einwirkenden kinetischen Energie, denen die Betonoberfläche ausgesetzt ist. Hierbei spielen sowohl der Anströmwinkel auf die Betonoberfläche als auch die auftretenden Fließgeschwindigkeiten und der damit einhergehende Feststofftransport in natürlichen Gewässern eine maßgebliche Rolle.
Neue Regelungen für den Grund‐ und Tunnelbau im Bundesfernstraßenbereich – Teil I: Grundbau
Authors: Friebel Wolf‐Dieter , Heimbecher Frank , Blosfeld Jürgen
Published: December 2007

Die technische Weiterentwicklung der Bauverfahren sowie die Herausgabe neuer nationaler und internationaler Normen und Regelwerke erforderten eine umfassende Überarbeitung der vorhandenen Regelungen des Bundesfernstraßenbereiches für den Grund‐ und Tunnelbau. In dieser Ausgabe werden die überarbeiteten Zusätzlichen Technischen Vertragsbedingungen und Richtlinien für den Grundbau, die ZTV‐ING Teil 2, vorgestellt. In der nächsten Ausgabe folgen die überarbeiteten Regelungen für den Tunnelbau.