bluuebunny/crossref_metadata_2025 huggingface dataset:
Cancer incidence and mortality in aircraft maintenance workers
Authors: D'Este Catherine , Attia John R. , Brown Anthony M. , Gibson Richard , Gibberd Robert , Tavener Meredith , Guest Maya , Horsley Keith , Harrex Warren , Ross James
Published: November 2007

Background

A cancer incidence and mortality study was conducted in response to health concerns raised by workers from F‐111 aircraft deseal/reseal fuel tank maintenance programs, to determine whether personnel exposed to deseal/reseal had an excess of cancers and mortality.

Methods

Number of deaths and cancers for individuals involved in F‐111 DSRS activities were matched against two Air Force comparison groups. Analyses were weighted to adjust for differences in age, exposure period and rank.

Results

Eight hundred seventy‐three exposed, 7,577 comparison group one, and 9,408 comparison group two individuals were matched against death and cancer data, with 431 cancers and 431 deaths. Cancer incidence was higher in the exposed group, with marginally significant increases of 40–50% (cancer incidence rate ratio range 1.45–1.62). Exposed group mortality was significantly lower than both comparison groups, likely due to survivor bias in the exposed group (mortality rate ratio range 0.33–0.44).

Conclusions

On the balance of probabilities, there is an increased risk of cancer associated with participation in F‐111 deseal/reseal activities. Am. J. Ind. Med. 51:16–23, 2008. © 2007 Wiley‐Liss, Inc.
Challenges in residential fall prevention: Insight from apprentice carpenters
Authors: Lipscomb Hester J. , Dale Ann Marie , Kaskutas Vicki , Sherman‐Voellinger Roslyn , Evanoff Bradley
Published: November 2007

Background

Falls remain a serious source of morbidity and mortality in residential construction despite considerable knowledge of risk factors and prevention strategies. While training is universally viewed as positive, we know little about its effectiveness in preventing residential falls.

Methods

A series of focus groups were conducted with union apprentice carpenters (n = 36) at varied levels of training to elicit input on factors that might influence the effectiveness of residential fall prevention training, including hazard awareness, timing of elements of formal instruction, jobsite mentoring, and workplace norms.

Results

While apprentices identified many residential fall hazards, they voiced little concern about work near unprotected vertical or horizontal openings such as stairwells, window openings or leading edges. On residential jobs, apprentices worked at heights immediately and were often exposed to hazards they had not yet been trained to handle. The quality of mentoring varied tremendously, and things they had been taught in school were often not the norm on these small worksites. Use of fall arrest equipment was uncommon. Job insecurity in this fast‐paced work environment influenced behaviors even when apprentices reported knowledge of safe procedures; this was more of a problem for less experienced apprentices.

Conclusions

These data provide compelling evidence that apprentices often do not apply safety principles they have been taught in school in the actual work environment, illuminating how attempts to empower workers through training alone can fall short. The findings have policy implications and demonstrate the importance of measuring more than knowledge when evaluating effectiveness of training. Am. J. Ind. Med. 51:60–68, 2008. © 2007 Wiley‐Liss, Inc.
Perfluorosulfonic ionomer solution in N,N‐dimethylformamide
Authors: Luan Yinghao , Zhang Yongming , Li Lei , Zhang Heng , Zhang Qing , Huang Zhongxi , Liu Yangang
Published: November 2007

The morphology of perfluorosulfonic ionomer molecules in N,N‐dimethylformamide was investigated at different concentrations. Rheological, dynamic light scattering (DLS), and scanning electron microscopy (SEM) measurements were performed on the prepared perfluorosulfonic ionomer solutions or films. The ionomer molecules shrank from rodlike granules to spherelike ones at relatively low concentrations, and the spherelike granules aggregated together to form aggregates at higher concentrations, with capillary liquid bridge force as the driving force. As the solvent evaporated slowly at room temperature, the SEM image showed that the film was loosely stacked by granules and that aggregates formed in the solution. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Preparation of single poly(lactic acid) composites
Authors: Li Ruihua , Yao Donggang
Published: November 2007

An approach for making poly(lactic acid) (PLA) single‐polymer composites (SPCs) on the basis of PLA's slowly crystallizing characteristics was investigated. As a slowly crystallizing polymer, PLA can be processed with standard polymer processing techniques into end‐use products with varied crystallinities, from amorphous films to highly crystalline fibers. In this study, amorphous PLA sheets and crystalline PLA fibers/fabrics were laminated and compression‐molded to form an SPC at a processing temperature substantially lower than PLA's melting temperature. The effects of the major process conditions on the performance of the SPC were studied. The processing temperature played a profound role in affecting the fiber–matrix bonding properties. As the processing temperature increased, a drastic improvement in the interfacial bonding occurred at a temperature of around 135°C, which indicated the lower boundary of the process window. The compression‐molded SPC exhibited enhanced mechanical properties; particularly, the tearing strength of the fabric‐reinforced SPC was almost an order higher than that of the nonreinforced PLA. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
A Series of Isolable Silanoic Thio‐, Seleno‐, and Telluroesters (LSi(X)OR) with Donor‐Supported SiX Double Bonds (L=β‐Diketiminate; X=S, Se, Te)
Authors: Yao Shenglai , Xiong Yun , Brym Markus , Driess Matthias
Published: November 2007

The first silicon analogues of carbonic (carboxylic) esters, the silanoic thio‐, seleno‐, and tellurosilylesters 3 (SiS), 4 (SiSe), and 5 (SiTe), were prepared and isolated in crystalline form in high yield. These thermally robust compounds are easily accessible by direct reaction of the stable siloxysilylene L(Si:)OSi(H)L′ 2 (L=HC(CMe)2[N(aryl)2], L′=CH[(CCH2)‐CMe][N(aryl)]2; aryl=2,6‐iPr2C6H3) with the respective elemental chalcogen. The novel compounds were fully characterized by methods including multinuclear NMR spectroscopy and single‐crystal X‐ray diffraction analysis. Owing to intramolecular N→Si donor–acceptor support of the SiX moieties (X=S, Se, Te), these compounds have a classical valence‐bond N+–Si–X− resonance betaine structure. At the same time, they also display a relatively strong nonclassical SiX π‐bonding interaction between the chalcogen lone‐pair electrons (nπ donor orbitals) and two antibonding SiN orbitals (σ*π acceptor orbitals mainly located at silicon), which was shown by IR and UV/Vis spectroscopy. Accordingly, the SiX bonds in the chalcogenoesters are 7.4 (3), 6.7 (4), and 6.9 % (5) shorter than the corresponding SiX single bonds and, thus, only a little longer than those in electronically less disturbed SiX systems (“heavier” ketones).
Silylmetalation of Alkenes
Authors: Nakamura Shinji , Yonehara Mitsuhiro , Uchiyama Masanobu
Published: November 2007

Silylmetalation of alkenes is challenging due to the low reactivity of the substrates. In contrast, carbometalation of alkenes has been realized through several innovative methods, including activation of the reagent and the substrate. A similar approach could be applicable to silylmetalation of alkenes, and we have recently developed a bimetal activation method using zincate complexes for this purpose. Here, we describe how the silylzincation of alkenes was achieved. First, the strategies for carbometalation of alkenes will be summarized. Secondly, the history and development of silylzincation chemistry are briefly described. Then the details of our findings related to two types of silylzincation of alkenes, as well as recent progress in mechanistic studies, are discussed. The key point in the silylzincation of alkenes proved to be the bimetal activation of the substrate. One metal (copper or titanium) strongly coordinates and activates the alkene moiety, and the other metal (zinc) acts as the electron acceptor from the silyl group by way of the alkene moiety. This dual activation concept is expected to be applicable to other combinations of metals, as well as to new types of reactions.
Rhodium‐Complex‐Catalyzed Asymmetric Hydrogenation: Transformation of Precatalysts into Active Species
Authors: Preetz Angelika , Drexler Hans‐Joachim , Fischer Christian , Dai Zhenya , Börner Armin , Baumann Wolfgang , Spannenberg Anke , Thede Richard , Heller Detlef
Published: November 2007

The use of diolefin‐containing rhodium precatalysts leads to induction periods in asymmetric hydrogenation of prochiral olefins. Consequently, the reaction rate increases in the beginning. The induction period is caused by the fact that some of the catalyst is blocked by the diolefin and thus not available for hydrogenation of the prochiral olefin. Therefore, the maximum reaction rate cannot be reached initially. Due to the relatively slow hydrogenation of cyclooctadiene (cod) the share of active catalysts increases at first, and this leads to typical induction periods. The aim of this work is to quantify the hydrogenation of the diolefins cyclooctadiene (cod) and norborna‐2,5‐diene (nbd) for cationic complexes of the type [Rh(ligand)(diolefin)]BF4 for the ligands Binap (1,1′‐binaphthalene‐2,2′‐diylbis(phenylphosphine)), Me‐Duphos (1,2‐bis(2,5‐dimethylphospholano)benzene, and Catasium in the solvents methanol, THF, and propylene carbonate. Furthermore, an approach is presented to determine the desired rate constant and the resulting respective pre‐hydrogenation time from stoichiometric hydrogenations of the diolefin complexes via UV/Vis spectroscopy. This method is especially useful for very slow diolefin hydrogenations (e.g., cod hydrogenation with the ligands Me‐Duphos, Et‐Duphos (1,2‐bis(2,5‐diethylphospholano)benzene), and dppe (1,2‐bis(diphenylphosphino)ethane).
Assessable Consequences of Through‐Bond Donor–Acceptor Interactions in β‐Aminoketones
Authors: Lampkins Andrew J. , Li Yan , Al Abbas Alexandre , Abboud Khalil A. , Ghiviriga Ion , Castellano Ronald K.
Published: November 2007

Reported are the syntheses of ester‐functionalized (6–8) and alkyl‐substituted (9) 1‐aza‐adamantanones; the easy handling of the compounds provides an opportunity to comprehensively study the fundamental changes in structure and reactivity that can accompany the donor–acceptor arrangement in rigid β‐aminoketones. X‐ray structural analysis of trione 6 and dione 7 reveals bond length and angle variations consistent with through‐bond (hyperconjugative) donor–acceptor interactions. Observed is a shortening of the CN bond, elongation of the central CC bond (to ≈1.6 Å), and a significant pyramidalization of the carbonyl carbon within the donor–σ‐acceptor pathway. UV/Vis spectra of 6–9 show a new absorption maximum (λmax=260–275 nm in three solvents), the so‐called “σ‐coupled transition”; the molar absorptivity scales with the number of carbonyl groups (for trione 6, ε ≈3000, for dione 7, ε ≈2000) and the band reversibly disappears upon addition of acid. IR and 13C NMR spectroscopic data show trends consistent with through‐bond donation to the carbonyl acceptor groups and commensurate weakening of the carbonyl π bond. High yielding acid‐mediated fragmentations are used to illustrate the effects of the donor–acceptor arrangement on the reactivity of the molecules. Given that donor–σ‐acceptor molecules have recently been found to show self‐assembly behavior and macromolecular properties linked to their unusual structure, the current analysis encourages further consideration of the systems in advanced materials applications.
Coordination‐Driven Self‐Assembly, Structures, and Dynamic Properties of Diplatinum Hexatriynediyl and Butadiynediyl Complexes in which the sp Carbon Chains are Shielded by sp3 Carbon Chains: Towards Endgroup–Endgroup Interactions
Authors: Owen Gareth R. , Stahl Jürgen , Hampel Frank , Gladysz John A.
Published: November 2007

Sequential reactions of trans‐(C6F5)(p‐tol3P)2Pt(CC)3SiEt3 (PtC6SiEt3) with nBu4N+ F− (THF/methanol), PtCl, KPF6/tBuOK, and CuCl give trans,trans‐[(C6F5){(p‐tol3P)2}Pt(CC)3Pt{(Pp‐tol3)2}(C6F5)] (PtC6Pt) in 95 % yield on multigram scales. Reactions of PtC6Pt and Ar2P(CH2)mPAr2 afford substitution products trans,trans‐[(C6F5){(Ar2P(CH2)mPAr2)}Pt(CC)3Pt{(Ar2P(CH2)mPAr2)}(C6F5)] (PtC6Pt‐m/Ar; m/Ar=8/p‐tol, 78 %; 10/Ph, 82 %; 11/Ph, 69 %; 12/Ph, 57 %; 14/p‐tol, 57 %; 14/p‐C6H4‐tBu, 71 %), in which the diphosphines span the square planar platinum endgroups. An analogous reaction with PEt3 gives a tetrakis PEt3 complex Pt′C6Pt′ (72 %). The crystal structures of PtC6Pt, Pt′C6Pt′, PtC6Pt‐10/Ph, PtC6Pt‐11/Ph, and PtC6Pt‐14/p‐tol or solvates thereof are compared. In PtC6Pt, the endgroups can avoid van der Waals contact, and define angles of 0°. In PtC6Pt‐14/p‐tol, the sp3 chains twist around the sp chain in a chiral double‐helical motif, with an endgroup/endgroup angle of 189°. The sp3 chains are too short to adopt analogous conformations in the other complexes, but laterally shield the sp chain. NMR spectroscopy shows that the helical enantiomers of PtC6Pt‐14/p‐tol rapidly interconvert in solution at low temperature. A crystal structure of PtC4Pt shows endgroups that are in van der Waals contact and define an angle of 41°. Reactions with Ar2P(CH2)8PAr2 give PtC4Pt‐8/Ar (Ar=Ph, 53 %; p‐tol, 87 %). Low‐temperature NMR spectroscopy establish non‐helical chiral conformations. Electrochemical oxidations of the diplatinum complexes are analyzed, the reversibilities of which decrease with increasing sp chain length.
Synthesis, Self‐Assembling Properties, and Atom Transfer Radical Polymerization of an Alkylated L‐Phenylalanine‐Derived Monomeric Organogel from Silica: A New Approach To Prepare Packing Materials for High‐Performance Liquid Chromatography
Authors: Rahman M. Mizanur , Czaun Miklós , Takafuji Makoto , Ihara Hirotaka
Published: November 2007

The monomer N′‐octadecyl‐Nα‐(4‐vinyl)‐benzoyl‐L‐phenylalanineamide (4) based on L‐phenylalanine has been simply but effectively synthesized, and its self‐assembling properties have been investigated. FTIR and a variable‐temperature 1H NMR spectroscopic investigation demonstrated that the aggregation of compound 4 in various organic solvents is due to the formation of intermolecular hydrogen bonds among the amide moieties. UV/Vis measurements indicated that the multiple π–π interactions of the phenyl groups also contribute to the self‐assembly. As was observed by 13C cross‐polarization magic‐angle spinning (CP/MAS) NMR and variable‐temperature 1H NMR measurements, the ordered alkyl chains also played an important role in the molecular aggregation by van der Waals interactions. Compound 4 was polymerized by surface‐initiated atom transfer radical polymerization from porous silica gel to prepare a packing material for HPLC. The results of thermogravimetric analysis showed that a relatively large amount of polymer was grafted onto the silica surface. The organic phase on silica was in a noncrystalline solid form in which the long alkyl chain exists in a less‐ordered gauche conformation. Analysis of chromatographic performance for polyaromatic hydrocarbon samples showed higher selectivity than conventional reversed‐phase HPLC packing materials.
Fast Lithium Ion Conduction in Garnet‐Type Li7La3Zr2O12.
Authors: Murugan Ramaswamy , Thangadurai Venkataraman , Weppner Werner
Published: November 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
New Monoterpenoids from Dracocephalum forrestii Aerial Parts.
Authors: Li Gan‐Peng , Zhao Jing‐Feng , Yang Li‐Juan , Yang Xiao‐Dong , Li Liang
Published: November 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Polypharmacy akathisia and associated suicide attempts
Authors: Popli Anand , Gupta Sanjay
Published: November 2007

We report a case of a 72‐year‐old gentleman who developed severe akathisia while on fluoxetine and neuroleptics in a setting of benzodiazepine withdrawal which was associated with a first‐time violent suicide attempt. Depression 1:53–55 (1993) © 1993 Wiley‐Liss, Inc.
The corticotropin releasing factor stimulation test in patients with major depression: Relationship to dexamethasone suppression test results
Authors: Krishnan K. Ranga R. , Rayasam Krishnaiah , Reed Deborah , Smith Mark , Chapell Phillip , Saunders William B. , Ritchie James C. , Carroll Bernard J. , Nemeroff Charles B.
Published: November 2007

Depressed patients have been reported to exhibit both a blunted ACTH response to corticotropin‐releasing factor (CRF) and abnormal suppression of plasma cortisol following the administration of dexamethasone. The purpose of the study was to determine the relationship between these two abnormalities. Twenty‐three depressed patients and eighteen control subjects received both a standard CRF stimulation test and the dexamethasone suppression test (DST). Nonsuppressors on the DST exhibited a blunted ACTH response to CRF; DST suppressors exhibited a normal ACTH response to CRF. This suggests that the two abnormalities of the hypothalamic‐pituitary‐adrenal (HPA) axis are related and may be due to similar pathopbysiological mechanisms. Depression 1:133–136 (1993). © 1993 Wiley‐Liss, Inc.
Patient identity in major depression
Authors: Gara Michael A. , Rosenberg Seymour , Woolfolk Robert L.
Published: November 2007

The purpose of this study was to determine whether a strong identification with the patient role at the beginning of treatment was prognostic of depressed symptoms and global level of functioning 9 months later. Subjects were 22 women and 14 men diagnosed with major depression using DSM‐III‐R criteria. Subjects described various identities and people, including “self as patient,” using a free‐response format. A clustering analysis of the free‐response descriptions was used to represent the degree of elaboration of descriptions of the “patient self” relative to descriptions of other identities and people. Subjects also completed several symptom scales (e.g., Beck Depression Inventory) and cognitive measures at the beginning of treatment and then again 9 months later. Greater negative elaboration of the patient identity predicted poorer outcome 9 months later, in terms of both self‐reported depression and level offunctioning. Hierarchical regressions showed that these results were not accounted for by measures of symptoms, functioning, personality, or cognition taken at the beginning oftreatment. Identities other than the “patient” identity did not predict outcome at follow‐up. A strong identification with the patient role appears to be associated with relatively slow recovery from clinical depression. Depression 1:257–262 (1993). © 1993 Wiley‐Liss, Inc.
Clinical significance of early non‐response in depressed patients
Authors: Boyer William F. , Feighner John P.
Published: November 2007

Many authorities recommend a 6‐week trial of an antidepressant before deciding whether the patient will have a favorable response. However, this length of time is frequently impractical, especially for hospitalized patients. Some data suggests that ultimate response to a tricyclic antidepressant may be predicted from improvement within the first few weeks. To investigate this issue the authors analyzed data from six 6‐week double‐blind, controlled trials of selective serotonin reuptake inhibitors. Five studies included a placebo control group and all had an active antidepressant control. Overall the data showed that if there is no improvement early in treatment the chance of meaningful response by week 6 is poor. If a patient on active drug does not have at least a 20% improvement in the HAMD score at any point during the first 4 weeks the chance of 6‐week response was 3.7%. If a patient did not have a 20% improvement at 4 weeks but did at one or more previous weeks the chance of 6‐week response was 23.1%. The overall response rate for the whole sample was 60.7%. Very similar results were obtained using the Clinical Global Impressions Scale. These data suggest that a full 6‐week trial of an antidepressant is usually not warranted if there is not at least some improvement during the first 4 weeks of the trial. Depression 2:32–35 (1994). © 1994 Wiley‐Liss, Inc.
Morbidity in treated bipolar disorder: A one‐year prospective study using daily life chart ratings
Authors: Denicoff Kirk D. , Blake Kimberly D. , Smith‐Jackson Earlian E. , Jacob Paula A. , Leverich Gabriele , Post Robert M.
Published: November 2007

In this paper we describe the use of systematic retrospective and prospective life chart methodology and document the substantial morbidity experienced even in closely monitored and aggressively treated bipolar patients rated on a daily basis for 1 year. 35 BP I (n = 26) and BP II (n = 9) patients were recruited for an ongoing treatment study comparing the prophylactic effects of lithium or carbamazepine for 1 year with a crossover to the other drug in the second year, and a third year on the combination of the two. Adjuncts such as antidepressants and neuroleptics were allowed in each phase when clinically required. The results of the combined cohort for the first year are presented in this manuscript. All patients also had a retrospective life chart completed to map affective episodes based on the degree of functional incapacity (mild, moderate, severe). For prospective ratings patients were usually interviewed biweekly (but at a minimum of every 4 weeks), and daily ratings integrating degree of functional incapacity and self‐rated mood based on the Life Chart Method and Manual (the NIMH‐LCM) were obtained. In the first year of treatment 12 patients (34.3%) had to have their treatment phase (lithium or carbamazepine) discontinued far the fallowing reasons: jive were hospitalized, five had severe dysfunction without hospitalization, and two had treatment‐limiting side effects. Adjunctive treatment was required by 71.4%. The mean number of days ill for each level of severity for all the patients was as follows (in days): 66.1, mild depression; 31.1, moderate depression; 2.8, severe depression; and 28.7, mild mania; 5.4, moderate mania; 0.9, severe mania; or a mean of 40.2 d/year with moderate to severe illness‐related dysfunction. The duration of illness prior to study entry correlated with time depressed in the prospective year. These findings suggest that closely‐monitored bipolar patients followed with prospective daily ratings during treatment with a primary mood stabilizer (carbamazepine or lithium) experience a substantial degree of morbidity and the need far adjunctive antidepressants and neuroleptics. There was notable continuity between course of illness life charted in the retrospective year and that observed prospectively. Depression 2:95–104 (1994). ©1994 Wiley‐Liss, Inc.
Acute and delayed effects of adrenocorticotropic hormone on dopamine activity in man
Authors: Posener Joel A. , Schildkraut Joseph J. , Williams Gordon H. , Gleason Ray E. , Salomon Melinda S. , Schatzberg Alan F.
Published: November 2007

This study was designed to test the hypothesis that administration of synthetic adrenocorticotropic hormone (co‐syntropin) to healthy human subjects produces an increase in plasma levels of homovanillic acid (HVA), the principal dopamine metabolite. Co‐syntropin 0.25 mg was administered intravenously at 8:35 <AM to healthy volunteer subjects having no active medical problems, personal psychiatric history, or family psychiatric history. In a sample of 12 subjects, plasma levels of cortisol and HVA were measured at baseline and then at 30 min intervals over the 3.5 h following co‐syntropin. In a subgroup of six subjects, these same measurements were obtained at baseline, then in the morning and afternoon on each of the 2 days following the day of co‐syntropin administration. We did not observe an increase in plasma HVA over the 3.5 h following co‐syntropin, but a statistically significant increase in plasma HVA was observed over the subsequent 2 days. These results suggest that ACTH may exert delayed effects on dopamine activity in man, although confirmation of our findings with a larger sample will be required. Depression 2:292–296 (1994/1995). © 1995 Wiley‐Liss, Inc.
Women's increased vulnerability to mood disorders: Integrating psychobiology and epidemiology
Authors: Blehar Mary C. , Oren Dan A.
Published: November 2007

Beyond the repeatedly confirmed finding that women greatly outnumber men among those diagnosed with mood disorders lies a widely‐varying set of hypotheses that attempt to explain affective disorders from various perspectives. This article reviews the epidemiological and diagnostic factors that account for the finding. In addition, we review some of the current hypothetical constructs of the etiology and pathophysiology of depression and their potential relevance to the disproportionate number of women with unipolar depression. Particular attention is paid to the unique biological stages of a women's life and the differences between the biology of men and women. We also review some of the potential social, psychological, and environmental factors that might particularly promote the development of depression in women. Depression 3:3–12 (1995). © 1995 Wiley‐Liss, Inc

This article is a US Government work and, as such, is in the public domain in the United States of America.

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Gender differences in coping with depression across the lifespan
Authors: Nolen‐Hoeksema Susan
Published: November 2007

Women are twice as likely as men to report high levels of depressive symptoms and to be diagnosed with a unipolar depressive disorder. I propose that throughout adolescence and adulthood women tend to have a more ruminative and passive style of responding to their own distress than men. This ruminative style of mood management exacerbates and prolongs the periods of distress that arise for women, and interferes with women's ability to overcome the negative events they face. I discuss evidence from experimental and field studies supporting this explanation of the gender differences in depression. I also describe a model for the emergence of gender differences in depression in early adolescence. Depression 3:81–90 (1995). © 1995 Wiley‐Liss, Inc.
Combination therapy and the depressed woman
Authors: Karp Jordan F. , Frank Ellen
Published: November 2007

While the question of the relative efficacy of combination pharmacotherapy and psychotherapy vs. either therapy alone has received some research attention within the last 25 years, the authors attempt to narrow the focus of this question by discussing the possibility that combination therapy may be of special value for women with major depression. Theoretical models explaining why combination therapy, in general, might be expected to be more effective are described. The authors then discuss reasons why combination therapy might be a particularly efficacious treatment for depressed women, including greater psychosocial stress prior to and resulting from depression and increased cognitive distortion, both of which are more associated with depression in females. Despite a reasonable theoretical rationale for the superiority of combination in comparison to either monotherapy, examination of the available literature on acute, continuation, and maintenance treatment studies generally failed to find benefits for the use of combination therapy. Similarly, examination of the literature for gender differences among patients treated with combination therapy failed to find a specific benefit of this treatment for women. Possible reasons for these findings and suggestions for future studies are discussed. Depression 3:91–98 (1995). © 1995 Wiley‐Liss, Inc.
Alextthymia in male cannabis users: The role of comorbid depressive disorders
Authors: Spalletta Gianfranco , Troisi Alfonso , Pasini Augusto
Published: November 2007

Whereas there is strong evidence for a high prevalence of alexithymia among patients with alcohol dependence and mixed substance abuse, no study has investigated the association between cannabis use and alexithymia. In this study, we assessed the prevalence of alexithymia, as measured by the 20‐item revised Toronto Alexithymia Scale (TAS‐20), in a group of newly abstinent cannabis abusers (N = 60) who abused cannabis exclusively. We found a large difference in the rate of alexithymia between cannabis abusers with and without comorbid DSM‐III‐R depressive disorders. Only 7% of nondepressed cannabis‐abusing subjects were alexithymic. In contrast, 57% of cannabis abusers with comorbid major depression, dysthymia, or adjustment disorder with depressed mood were alexithymic. The prevalence rate of alexithymia among the cannabis abusers with comorbid depressive disorders was similar to that (50%) found in a control group of pure depressives, even though the TAS‐20 F1 subscale discriminated between the two groups (depressed cannabis abusers had more difficulty identifying their feelings than pure depressives). These results suggest that a syndromal diagnosis of comorbid depression may be a major confounding variable in the assessment of alexithymia (as measured by the TAS total score) among subjects with cannabis abuse and dependence. Depression 3:246–249 (1995/1996). © 1996 Wiley‐Liss, Inc.
Carbamazepine increased pregnenolone synthesis blocked by peripheral type benzodiazepine receptor antagonist
Authors: Pan Bai‐Shen , Manji Husseini K. , Schmidt Mark E. , Potter William Z.
Published: November 2007

Despite the widespread use of carbamazepine (CBZ) in the treatment of a number of neuropsychiatric disorders, its mechanism(s) of action remain to be elucidated. In view of the postulated interaction of CBZ with peripheral type benzodiazepine (BDZ) receptors and the role of these receptors in regulating neuroactive steroid biosynthesis, we investigated the effects of CBZ on pregnenolone accumulation in cultured rat C6 glioma cells. We found that CBZ elevates pregnenolone accumulation over a period of 60 min, and that this effect was not due to inhibition of pregnenolone metabolism. Preincubation of C6 cells with the selective peripheral type benzodiazepine receptor antagonist PK11195 blocked the CBZ‐induced elevation in pregnenolone‐induced elevation in pregnenolone accumulation. The results suggest that CBZ stimulated pregnenolone biosynthesis in cultured C6 cells involves a direct or indirect interaction with peripheral type benzodiazepine receptors. These effects may provide additional insights into the mechanisms by which CBZ regulates neuronal excitability. Depression 3:267‐y (1995/1996). © 1996 Wiley‐Liss, Inc

This article is a US Government work and, as such, is in the public domain in the United States of America.

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The behavior of specific sediment yield in different grain size fractions in the tributaries of the middle Yellow River as influenced by eolian and fluvial processes
Authors: Xu Jiongxin
Published: November 2007

Based on data from 35 stations on the tributaries of the Yellow River, annual specific sediment yield (Ys) in eight grain size fractions has been related to basin‐averaged annual sand–dust storm days (Dss) and annual precipitation (Pm) to reveal the influence of eolian and fluvial processes on specific sediment yield in different grain size fractions. The results show that Ys in fine grain size fractions has the highest values in the areas dominated by the coupled wind–water process. From these areas to those dominated by the eolian process or to those dominated by the fluvial process, Ys tends to decrease. For relatively coarse grain size fractions, Ys has monotonic variation, i.e. with the increase in Dss or the decrease in Pm, Ys increases. This indicates that the sediment producing behavior for fine sediments is different from that for relatively coarse sediments. The results all show that Ys for relatively coarse sediments depends on the eolian process more than on the fluvial process, and the coarser the sediment fractions the stronger the dependence of the Ys on the eolian process. The Ys–Dss and Ys–Pm curves for fine grain size fractions show some peaks and the fitted straight lines for Ys–Dss and Ys–Pm relationships for relatively coarse grain size fractions show some breaks. Almost all these break points may be regarded as thresholds. These thresholds are all located in the areas dominated by the coupled wind–water process, indicating that these areas are sensitive for erosion and sediment production, to which more attention should be given for the purpose of erosion and sediment control. A number of regression equations were established, based which the effect of rainfall, sand–dust storms and surface material grain size on specific sediment yield can be assessed. Copyright © 2007 John Wiley & Sons, Ltd.
AIDS dementia complex and Hashimoto encephalopathy in a senescent woman
Authors: Waltereit Robert , Schulte‐Brochterbeck Gudrun , Wiltfang Jens , Frölich Lutz
Published: November 2007

AIDS dementia complex is one of the specific infectious dementias, which is rarely seen in senescent (>75 years of age) subjects. Hashimoto encephalopathy has been described as the cause of several neurological and psychiatric syndromes including dementia. The proposed pathophysiological mechanism is an autoimmune reaction to shared, thyroid gland and CNS epitopes with subsequent cerebral dysfunction. We report here the first case of a patient who fulfils both, the criteria for AIDS dementia complex and Hashimoto encephalopathy, yet being unresponsive to steroid therapy. Diagnostic and therapeutic implications are discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Characterization of ionotrophic purinergic receptors in hepatocytes
Authors: Emmett Daniel S. , Feranchak Andrew , Kilic Gordan , Puljak Livia , Miller Bonnie , Dolovcak Svjetlana , McWilliams Ryan , Doctor Brian R. , Fitz Gregory J.
Published: November 2007

Ionotrophic purinergic (P2X) receptors function as receptor-gated cation channels, where agonist binding leads to opening of a nonselective cation pore permeable to both Na+ and Ca2+. Based on evidence that extracellular adenosine 5′-triphosphate (ATP) stimulates glucose release from liver, these studies evaluate whether P2X receptors are expressed by hepatocytes and contribute to ATP-dependent calcium signaling and glucose release. Studies were performed in isolated hepatocytes from rats and mice and hepatoma cells from humans and rats. Transcripts and protein for both P2X4 and P2X7 were detectable, and immunohistochemistry of intact liver revealed P2X4 in the basolateral and canalicular domains. In whole cell patch clamp studies, exposure to the P2X4/P2X7 receptor agonist 2′3′-
O

-(4-benzoyl-benzoyl)-adenosine 5′-triphosphate (BzATP; 10 μM) caused a rapid increase in membrane Na+ conductance. Similarly, with Fluo-3 fluorescence, BzATP induced an increase in intracellular [Ca2+]. P2X4 receptors are likely involved because the calcium response to BzATP was inhibited by Cu2+, and the P2X4 modulators Zn2+ and ivermectin (0.3-3 μM) each increased intracellular [Ca2+]. Exposure to BzATP decreased cellular glycogen content; and P2X4 receptor messenger RNA increased in glycogen-rich liver samples.

Conclusion:

These studies provide evidence that P2X4 receptors are functionally important in hepatocyte Na+ and Ca2+ transport, are regulated by extracellular ATP and divalent cation concentrations, and may constitute a mechanism for autocrine regulation of hepatic glycogen metabolism. (Hepatology 2007.)
Acute phase response induction by cancer treatment with photodynamic therapy
Authors: Korbelik Mladen , Cecic Ivana , Merchant Soroush , Sun Jinghai
Published: November 2007

Inflammation and immunity development are well recognized as responses to tumor treatment by photodynamic therapy (PDT). To demonstrate that another major host response effector process, acute phase response, may be also induced by this cancer treatment modality, the expression of serum amyloid P component (SAP) acknowledged as a hallmark acute phase reactant in the mouse was investigated following PDT of murine FsaR fibrosarcomas. The results reveal almost 150‐fold increase in the expression of SAP gene in the liver of mice bearing tumors treated by Photofrin‐mediated PDT, while serum SAP levels increased around 50‐fold at the peak interval about 24 hr post PDT. The same tumor treatment induced also the liver gene upregulation and serum levels elevation of another established acute phase reactant, mannose‐binding lectin A (MBL‐A). Both SAP and MBL‐A were found to accumulate in PDT‐treated tumors, but this includes local production because their genes in these tumor tissues were upregulated as well. Gene encoding C‐reactive protein (CRP) was also upregulated almost 7‐fold in the same tumor tissues, suggesting a rare example of CRP participation in host response of the mouse. Interleukin‐6 and glucocorticoid hormones were identified as major mediators promoting tumor PDT‐induced upregulation of liver SAP gene. Moreover, glucocorticoids were found to act as critical inducers of SAP gene upregulation in PDT‐treated tumors. The study definitely proves the occurrence of a strong acute phase response following tumor PDT, and reveals that glucocorticoid hormones released during this development impact the expression of host response‐relevant genes in PDT‐treated tumors. © 2007 Wiley‐Liss, Inc.
Matuzumab and cetuximab activate the epidermal growth factor receptor but fail to trigger downstream signaling by Akt or Erk
Authors: Yoshida Takeshi , Okamoto Isamu , Okabe Takafumi , Iwasa Tsutomu , Satoh Taroh , Nishio Kazuto , Fukuoka Masahiro , Nakagawa Kazuhiko
Published: November 2007

Molecular inhibition of the epidermal growth factor receptor (EGFR) is a promising anticancer strategy, and monoclonal antibodies (mAbs) to EGFR are undergoing extensive evaluation in preclinical and clinical trials. However, the effects of anti‐EGFR mAbs on EGFR signaling have remained unclear. We have now examined the effects of 2 anti‐EGFR mAbs, matuzumab (EMD72000) and cetuximab (Erbitux), both of which are currently under assessment for treatment of various cancers, on EGFR signal transduction and cell survival in nonsmall cell lung cancer cell lines. Similar to EGF, matuzumab and cetuximab each induced phosphorylation of EGFR at several tyrosine phosphorylation sites as a result of receptor dimerization and activation of the receptor tyrosine kinase. In contrast to the effects of EGF, however, EGFR activation induced by these antibodies was not accompanied by receptor turnover or by activation of downstream signaling pathways that are mediated by Akt and Erk and are important for regulation of cell proliferation and survival. In addition, clonogenic survival assays revealed that matuzumab and cetuximab reduced the survival rate of H292 cells, in which they also inhibited the EGF‐induced activation of Akt and Erk. Although we have examined only a few cell lines, our results indicate that the antitumor effects of matuzumab and cetuximab depend on inhibition of EGFR downstream signaling mediated by Akt or Erk rather than on inhibition of EGFR itself. © 2007 Wiley‐Liss, Inc.
The Dickkopf‐homolog 3 is expressed in tumor endothelial cells and supports capillary formation
Authors: Untergasser Gerold , Steurer Michael , Zimmermann Martina , Hermann Martin , Kern Johann , Amberger Albert , Gastl Günther , Gunsilius Eberhard
Published: November 2007

A critical event in tumor growth and progression is the upregulation of angiogenesis. Thus, targeting angiogenesis has become an attractive treatment modality in cancer medicine. Our study analyzed various solid tumor types for the expression of Dkk‐3, a cystein‐rich, N‐glycosylated secreted member of the dickkopf protein family that has been proposed as a tumor suppressor gene. Tissue microarrays of gliomas (n = 30), high‐grade non‐Hodgkin's lymphomas (NHL, n = 80), colorectal cancer (n = 35) and melanoma (n = 30) were immunohistochemically analyzed for Dkk‐3 and CD31 expression. Moreover, the effects of Dkk‐3 were studied in vitro in primary endothelial colony‐forming cells (ECFC) and in vivo in a mouse melanoma model. In comparison to normal tissue, the number of blood vessels expressing Dkk‐3 was increased in glioma, high‐grade NHL, melanoma and colorectal carcinoma. Confocal laser scanning microscopy revealed that Dkk‐3 vesicles localized also in Weibel Palade bodies. In vitro cell proliferation and migration of ECFC was not significantly affected by adenoviral overexpression or siRNA‐mediated downregulation of Dkk‐3. Interestingly, tube formation in matrigel decreased after downregulation of Dkk‐3 and increased after adenoviral overexpression. Stable overexpression of murine Dkk‐3 in B16F10 cells significantly increased microvessel density in the C57/BL6 melanoma model. Thus, we postulate a novel function of Dkk‐3 in endothelial cells as a differentiation factor involved in remodeling the tumor vasculature. © 2007 Wiley‐Liss, Inc.
Determining transition state structure using kinetic isotope effects
Authors: Westaway Kenneth C.
Published: November 2007

Kinetic isotope effects (KIEs) have been found to be the most powerful tool available to physical organic chemists for determining the mechanism of reactions and for estimating the structure of their transition states. Various types of KIEs including primary‐leaving group‐, nucleophile‐, and α‐carbon KIEs and secondary alpha‐ and beta‐deuterium KIEs are introduced. The factors that affect the magnitude of each of these KIEs are covered in some detail. Finally, the use of these KIEs to determine the mechanism of a reaction and to estimate the structure of the transition state for a reaction is discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Isotope effect on chemical shifts in hydrogen‐bonded systems
Authors: Hansen Poul Erik
Published: November 2007

An overview of recent developments in the use of isotope effects in hydrogen‐bonded systems with special emphasis on intramolecular hydrogen bonding is given. The systems investigated cover both resonance‐assisted hydrogen bonded (RAHB) and non‐RAHB systems. Deuterium isotope effects on 13C chemical shifts are discussed extensively together with effects on 1H, 19F and 15N chemical shifts. The compounds cover a large range from hydrogen‐bonded esters over amides, thioamides, Schiff bases also covering proteins, nucleic acids and carbohydrates. Isotope effects are discussed both in static and tautomeric systems and in the liquid and solid states. Theoretical approaches to isotope effects on chemical shifts are likewise treated. Copyright © 2007 John Wiley & Sons, Ltd.
High‐flow and flood trends in a network of undisturbed catchments in the UK
Authors: Hannaford Jamie , Marsh Terry J.
Published: November 2007

This study presents the results of trend tests applied to high‐flow and flood records from a network of catchments in the UK. These rivers have flow regimes which are relatively undisturbed by anthropogenic influences, enabling a characterization of natural, climate‐driven trends. Trend tests were applied to indicators of flood magnitude and frequency, and also indicators of high‐flow magnitude (10‐ and 30‐day maxima) and duration (prevalence of high‐flows). Significant positive trends over the 30–40 years leading up to 2003 were identified in all indicators, and these were primarily found in upland, maritime‐influenced catchments in northern and western areas of the UK. The results suggest a trend towards more protracted high‐flows and more spate conditions in northern and western areas, but trends in flood magnitude were less prevalent. Few compelling trends were found in the English lowlands, where significant high‐flow trends were influenced by a sequence of notable flood events through the exceptionally wet winter of 2000/1. The observed trends have parallels with some projections for extreme rainfall changes under climate change scenarios. However, high‐flow indicators for many northern and western catchments were correlated with the North Atlantic Oscillation (NAO), so recent increases are probably caused by a shift towards a more prevalent positive NAO since the 1960s. Six longer (>55 years) hydrometric records were used to place recent trends in a historical context; there was little evidence for trend in the longer time series, but fluctuations in the records suggest that recent trends may be influenced by multi‐decadal variability, which has important consequences for trend detection as the majority of UK gauging station records begin in a relatively quiescent period for high‐flows. Copyright © 2007 Royal Meteorological Society
Monolithic stationary phase coupled with coulometric detection: Development of an ion‐pair HPLC method for the analysis of quinone‐bearing compounds
Authors: Mancini Francesca , Bolognesi Maria L. , Melchiorre Carlo , Cavalli Andrea , Andrisano Vincenza
Published: November 2007

Memoquin, a recently discovered new drug candidate for the treatment of Alzheimer's disease (AD), is a compound able to interfere with different key targets of AD neurodegeneration. In the present work, the electroactivity of Memoquin, due to the presence of a quinone ring in the molecule, was exploited for the development of a sensitive and selective HPLC chromatographic method with coulometric detection system. For this purpose, a monolithic silica‐based stationary phase (Chromolith C18) was coupled with ESA detector and under high flow rate condition (2 mL/min) gave an efficient coulometric detection without a significant backpressure. The monolithic stationary phase and the electrochemical detection were combined to obtain a very fast (less than 7 min) and sensitive analysis of the compound of interest. For this reason, the method was found suitable to determine Memoquin with very high sensitivity (LOD, 0.005 μg/mL; LOQ, 0.016 μg/mL), better than with UV and fluorescence detections, and selectivity resulting potentially suitable for its analysis in biological samples. Moreover, the HPLC method was employed for the separation of Memoquin from other quinone analogs (endowed with different substituent on the quinone ring and length of the lateral chain) and allowed the comparison of the electrochemical properties of the compounds of the series. In the optimized chromatographic conditions it was possible to separate each quinone and to evaluate the influence of the substituent of the quinone ring on the electrochemical properties of the molecule.
Chromatographic characterisation of a novel type of monolithic methylsilsesquioxane‐based HPLC column
Authors: Popp Maximilian , Sulyok Michael , Rosenberg Erwin
Published: November 2007

A novel monolithic methylsilsesquioxane‐based material with hierarchical pore structure was prepared and tested for its applicability as stationary phase for RP‐HPLC. The monolithic material is produced using sol–gel chemistry according to a proprietary protocol developed in our working group. A procedure for the production of HPLC columns from the self‐contained monolithic material is described. The chromatographic performance and the reproducibility of the column production was tested using the procedures of the widely accepted Tanaka test and suitable parts of the Engelhardt test which were applied to a set of four monolithic columns produced under identical conditions. The test proved the excellent hydrophobic selectivity and silanophilic behaviour of the new stationary phase material. According to the tests on steric and shape selectivity, there are strong indications that this type of material also acts as restricted access material. This assumption is further supported by the presence of a high fraction of micropores as was evidenced by physical characterisation of the material. The novel stationary phase material showed great potential for the separation of small apolar substances and was found to be particularly useful in the separation of basic compounds due its excellent silanophilic interaction.