bluuebunny/crossref_metadata_2025_split huggingface dataset:
Using species‐environmental amplitudes to predict pH values from vegetation
Authors: Peppler‐Lisbach Cord 
Published: March 2008

AbstractQuestion: Species optima or indicator values are frequently used to predict environmental variables from species composition. The present study focuses on the question whether predictions can be improved by using species environmental amplitudes instead of single values representing species optima.Location: Semi‐natural, deciduous hardwood forests of northwestern Germany.Methods: Based on a data set of 558 relevés, species responses (presence/absence) to pH were modelled with Huisman‐Olff‐Fresco (HOF) regression models. Species amplitudes were derived from response curves using three different methods. To predict the pH from vegetation, a maximum amplitude overlap method was applied. For comparison, predictions resulting from several established methods, i. e. maximum likelihood/present and absent species, maximum likelihood/present species only, mean weighted averages and mean Ellenberg indicator values were calculated. The predictive success (squared Pearson's r and root mean square error of prediction) was evaluated using an independent data set of 151 relevés.Results: Predictions based upon amplitudes defined by maximum Cohen's x probability threshold yield the best results of all amplitude definitions (R2= 0.75, RMSEP = 0.52). Provided there is an even distribution of the environmental variable, amplitudes defined by predicted probability exceeding prevalence are also suitable (R2= 0.76, RMSEP = 0.55). The prediction success is comparable to maximum likelihood (present species only) and – after rescaling – to mean weighted averages. Predicted values show a good linearity to observed pH values as opposed to a curvilinear relationship of mean Ellenberg indicator values. Transformation or rescaling of the predicted values is not required.Conclusions: Species amplitudes given by a minimum and maximum boundary for each species can be used to efficiently predict environmental variables from species composition. The predictive success is superior to mean Ellenberg indicator values and comparable to mean indicator values based on species weighted averages.
Neuropeptides: Chemical Activity Profiling and Proteomic Approaches
Authors: Hook Vivian , Hwang Shin‐Rong , Wegrzyn Jill , Bark Steven 
Published: March 2008

AbstractPeptide neurotransmitters and peptide hormones, collectively known as neuropeptides, are required for cell–cell communication in neurotransmission and for regulation of endocrine functions. Neuropeptides are synthesized from protein precursors (termed proneuropeptides or prohormones) that require proteolytic processing within secretory vesicles that store and secrete active neuropeptides. This article describes the application of chemical biological approaches advantageously used to define protease pathways involved in neuropeptide biosynthesis. Activity profiling of proteases, combined with mass spectrometry, has allowed identification of the novel cathepsin L cysteine protease pathway for neuropeptide biosynthesis, which contributes to neuropeptide production with the subtilisin‐like prohormone convertase pathway. Furthermore, proteomic approaches for identifying proteases and protein systems present in secretory vesicles define the protease pathways and the functional protein systems that jointly operate in the secretory vesicle for production and secretion of active neuropeptides. Neuropeptidomic approaches allow defined primary structural analyses of neuropeptides. Future studies that gain understanding of protease mechanisms for generating active neuropeptides will be instrumental for translational research to develop therapeutic strategies for health and disease.
Autologous stem cell transplantation in patients of 70 years and older with multiple myeloma: Results from a matched pair analysis
Authors: Kumar Shaji K. , Dingli David , Lacy Martha Q. , Dispenzieri Angela , Hayman Suzanne R. , Buadi Francis K. , Rajkumar S. Vincent , Litzow Mark R. , Gertz Morie A. 
Published: March 2008

AbstractHigh‐dose therapy and autologous stem cell transplant (HDT) have been shown to prolong survival in multiple myeloma (MM) in randomized trials, but only included patients of 65 years or younger. Given the median age at diagnosis of 66 years, it is important to have a better understanding of the outcome of transplantation in the older patients. We identified 33 patients with MM, who were ≥70 years at the time of their HDT. We matched them to a group of 60 patients, 65 years or younger, (two controls for each patient), based on time to transplant, disease status at transplant, Durie‐Salmon stage, labeling index, presence of cytogenetic abnormalities, and presence of circulating plasma cells. The median age of the two groups were 55.6 (range, 37.3–64.9) and 71.7 (range 70–75.8) years at transplant. Although more of the older patients received dose reduced melphalan, the overall response rate was similar (97% vs. 98%) as was the median time to progression (28.5 months vs. 17.8 months, P = 0.7) for the elderly group compared to the younger patients. The median overall survival from transplant was not reached for the elderly patient group compared to 53.2 months for the younger patients, P = 0.7. HDT is feasible in selected patients with multiple myeloma over 70 years. The toxicity of transplant as well as the outcome appears comparable to younger patients. Patients with MM should not be excluded from HDT solely on the basis of their chronological age. Am. J. Hematol., 2008. © 2008 Wiley‐Liss, Inc.
Occupational health and safety experience of day laborers in seattle, WA
Authors: Seixas Noah S. , Blecker Hillary , Camp Janice , Neitzel Rick 
Published: March 2008

AbstractBackgroundDay Labor is a growing part of the informal economy in the US, and in Seattle, and may entail a high risk of injury and illness at work.MethodsWe surveyed 180‐day laborers, at two worker centers and an unregulated “Street” location concerning their job‐specific exposures and injury experience.ResultsExposures to both health and safety hazards were common at all three sites. After controlling for type of work, immigrant workers were 1.5–2 times more likely than non‐immigrant day laborers to report exposure to hazardous conditions. Among the 180 participants 34 reported injuries were classified as “recordable.” We estimated an injury rate of 31 recordable injuries per 100 full time employees. The three hiring locations had differing job experiences and exposures. Those hired through worker centers had a lower risk of exposures, while the Street workers were more likely to refuse hazardous work.ConclusionsDay laborers are exposed to numerous hazards at work, resulting in high injury rates. Multiple approaches including community based organizations which may provide some employment stability and social support for protection at work are needed to reduce occupational injury and illness risk among these vulnerable populations. Am. J. Ind. Med. 51:399–406, 2008. © 2008 Wiley‐Liss, Inc.
Rational Design of Mesoporous Metals and Related Nanomaterials by a Soft‐Template Approach
Authors: Yamauchi Yusuke , Kuroda Kazuyuki 
Published: March 2008

AbstractWe review recent developments in the preparation of mesoporous metals and related metal‐based nanomaterials. Among the many types of mesoporous materials, mesoporous metals hold promise for a wide range of potential applications, such as in electronic devices, magnetic recording media, and metal catalysts, owing to their metallic frameworks. Mesoporous metals with highly ordered networks and narrow pore‐size distributions have traditionally been produced by using mesoporous silica as a hard template. This method involves the formation of an original template followed by deposition of metals within the mesopores and subsequent removal of the template. Another synthetic method is the direct‐template approach from lyotropic liquid crystals (LLCs) made of nonionic surfactants at high concentrations. Direct‐template synthesis creates a novel avenue for the production of mesoporous metals as well as related metal‐based nanomaterials. Many mesoporous metals have been prepared by the chemical or electrochemical reduction of metal salts dissolved in aqueous LLC domains. As a soft template, LLCs are more versatile and therefore more advantageous than hard templates. It is possible to produce various nanostructures (e.g., lamellar, 2D hexagonal (p6mm), and 3D cubic (Ia$\bar 3$d)), nanoparticles, and nanotubes simply by controlling the composition of the reaction bath.
Patterns of intraneural ganglion cyst descent
Authors: Spinner Robert J. , Carmichael Stephen W. , Wang Huan , Parisi Thomas J. , Skinner John A. , Amrami Kimberly K. 
Published: March 2008

AbstractOn the basis of the principles of the unifying articular theory, predictable patterns of proximal ascent have been described for fibular (peroneal) and tibial intraneural ganglion cysts in the knee region. The mechanism underlying distal descent into the terminal braches of the fibular and tibial nerves has not been previously elucidated. The purpose of this study was to demonstrate if and when cyst descent distal to the articular branch‐joint connection occurs in intraneural ganglion cysts to understand directionality of intraneural cyst propagation. In Part I, the clinical records and MRIs of 20 consecutive patients treated at our institution for intraneural ganglion cysts (18 fibular and two tibial) arising from the superior tibiofibular joint were retrospectively analyzed. These patients underwent cyst decompression and disconnection of the articular branch. Five of these patients developed symptomatic cyst recurrence after cyst decompression without articular branch disconnection which was done elsewhere prior to our intervention. In Part II, five additional patients with intraneural ganglion cysts (three fibular and two tibial) treated at other institutions without disconnection of the articular branch were compared. These patients in Parts I and II demonstrated ascent of intraneural cyst to differing degrees (12 had evidence of sciatic nerve cross‐over). In addition, all of these patients demonstrated previously unrecognized MRI evidence of intraneural cyst extending distally below the level of the articular branch to the joint of origin: cyst within the proximal most portions of the deep fibular and superficial fibular branches in fibular intraneural ganglion cysts and descending tibial branches in tibial intraneural ganglion cysts. The patients in Part I had complete resolution of their cysts at follow‐up MRI examination 1 year postoperatively. The patients in Part II had intraneural recurrences postoperatively within the articular branch, the parent nerve, and the terminal branches, although in three cases they were subclinical. The authors demonstrate that cyst descent distal to the take‐off of the articular branch to the joint of origin occurs regularly in patients with fibular and tibial intraneural ganglion cysts. The authors believe that parent terminal branch descent follows ascent up the articular branch from an affected joint of origin. This mechanism for bidirectional flow explains cyst within terminal branches of the fibular and tibial nerves and is dependent on pressure fluxes and resistances. This new pattern is consistent with principles previously described in a unified (articular) theory, is generalizable to other intraneural ganglion cysts arising from joints, and has important implications for pathogenesis and treatment of these intraneural cysts. Clin. Anat. 21:233–245, 2008. © 2008 Wiley‐Liss, Inc.
Fusion Peptides and Transmembrane Domains of Fusion Proteins are Characterized by Different but Specific Structural Properties
Authors: Weise Katrin , Reed Jennifer 
Published: March 2008

AbstractMembrane fusion is essential for many biological processes. Though there have been many structure and fusion studies of cellular and viral fusion proteins in the last years, their functional mechanism remains elusive. In particular, the structural modes of operation of the transmembrane domains and viral fusion peptides of fusion proteins during membrane fusion have not been elucidated, although work on de novo designed fusogenic peptides suggested that conformational flexibility was necessary. In addition, the use of different and incompatible measurement criteria has made a comparative overview difficult. Here, we report a systematic structural analysis of viral fusion peptides from different fusion protein classes and transmembrane domains of viral and cellular fusion proteins by using circular dichroism spectroscopy. The data that were obtained demonstrate that class I viral fusion peptides show a structural flexibility between helix and irregular secondary structures, whereas fusion peptides of class II viral fusion proteins are characterized by a stable random coil and turn structure. Thus, conformational flexibility does not seem to be a universal criterion for the fusion activity of a fusion peptide. On the contrary, the transmembrane domains of fusion proteins are distinguished by a structural flexibility between helix and sheet structure that is similar to de novo designed unnatural peptides with high fusion activities (M. W. Hofmann et al. PNAS 2004, 101, 14 776‐14 781). Thus, the conformational behavior of the fusogenic unnatural peptides most closely resembles that of fusion protein transmembrane domains, and allows them to be used to gain a deeper understanding of the membrane fusion process.
A Multimeric Quinacrine Conjugate as a Potential Inhibitor of Alzheimer's β‐Amyloid Fibril Formation
Authors: Dolphin Gunnar T. , Chierici Sabine , Ouberai Myriam , Dumy Pascal , Garcia Julian 
Published: March 2008

AbstractAmyloid formation and accumulation of the amyloid β‐peptide (Aβ) in the brain is associated with Alzheimer's disease (AD) pathogenesis. Therefore, among the therapeutic approaches in development to fight the disease, the direct inhibition of the Aβ self‐assembly process is currently widely investigated and is one of the most promising approaches. In this study we investigated the potential of a multimeric display of quinacrine derivatives, as compared to the monomer quinacrine, as a design principal for a novel class of inhibitors against Aβ fibril formation. The presented multimeric conjugate exhibits a cluster of four quinacrine derivatives on a rigid cyclopeptidic scaffold. Herein is reported the synthesis of the conjugate, together with the in vitro inhibitory evaluation of Aβ1–40 fibrils using the thioflavin T fluorescence assay, and imaging with atomic force microscopy. Our data show that the multimeric compound inhibits Aβ1–40 fibril formation with an IC50 value of 20±10 μM, which contrasts with the nonactive monomeric analogue. This work suggests that assembling multiple copies of acridine moieties to a central scaffold, for multiple interactions, is a promising strategy for the engineering of inhibitors against Aβ fibril formation.
Synthesis of Novel Structurally Simplified Estrogen Analogues
Authors: Tietze Lutz F. , Vock Carsten A. , Krimmelbein Ilga K. , Wiegand J. Matthias , Nacke Linda , Ramachandar Tokala , Islam Kazi M. D. , Gatz Christiane 
Published: March 2008

AbstractA library of 17 novel estrogen analogues 3 and 4 containing different substituents at rings A and D (steroid nomenclature) was prepared in a five‐ to seven‐step synthesis. The key transformation is a Sonogashira‐coupling of cyclic vinyl iodides of type 7 or 8 with phenylacetylenes of type 9. Reduction of the keto function in 3 led to the estradiol analogue 5.
Anisotropic contraction in forisomes: Simple models won't fit
Authors: Peters Winfried S. , Knoblauch Michael , Warmann Stephen A. , Pickard William F. , Shen Amy Q. 
Published: March 2008

AbstractForisomes are ATP‐independent, Ca2+‐driven contractile protein bodies acting as reversible valves in the phloem of plants of the legume family. Forisome contraction is anisotropic, as shrinkage in length is associated with radial expansion and vice versa. To test the hypothesis that changes in length and width are causally related, we monitored Ca2+‐ and pH‐dependent deformations in the exceptionally large forisomes of Canavalia gladiata by high‐speed photography, and computed time‐courses of derived geometric parameters (including volume and surface area). Soybean forisomes, which in the resting state resemble those of Canavalia geometrically but have less than 2% of the volume, were also studied to identify size effects. Calcium induced sixfold volume increases in forisomes of both species; in soybean, responses were completed in 0.15 s, compared to about 0.5 s required for a rapid response in Canavalia followed by slow swelling for several minutes. This size‐dependent behavior supports the idea that forisome contractility might rest on similar mechanisms as those of polyelectrolyte gels, a class of artificial “smart” materials. In both species, time‐courses of forisome length and diameter were variable and lacked correlation, arguing against a simple causal relationship between changes in length and width. Moreover, changes in the geometry of soybean forisomes differed qualitatively between Ca2+‐ and pH‐responses, suggesting that divalent cations and protons target different sites on the forisome proteins. Cell Motil. Cytoskeleton 2008. © 2008 Wiley‐Liss, Inc.
MYH9‐siRNA and MYH9 mutant alleles: Expression in cultured cell lines and their effects upon cell structure and function
Authors: Li Yan , Friedmann David R. , Mhatre Anand N. , Lalwani Anil K. 
Published: March 2008

AbstractMYH9 encodes a class II nonmuscle myosin heavy chain‐A (NMHC‐IIA), a widely expressed 1960 amino acid polypeptide, with translated molecular weight of 220 kDa. From studies of type II myosin in invertebrates and analogy with the skeletal and smooth muscle myosin II, NMHC‐IIA is considered to be involved in diverse cellular functions, including cell shape, motility and division. The current study assessed the consequences of two separate, naturally occurring MYH9 dominant mutant alleles, MYH9R702C and MYH9R705H linked to syndromic and nonsyndromic hearing loss, respectively, upon diverse NMHC‐IIA related functions in two separate cultured cell lines. MYH9‐siRNA‐induced inhibition of NMHC‐IIA in HeLa cells or HEK293 cells resulted in alterations in their shape, actin cytoskeleton and adhesion properties. However, HeLa or HEK293 cells transfected with naturally occurring MYH9 mutant alleles, MYH9R702C or MYH9R705H, as well as in vitro generated deletion derivatives, MYH9ΔN592 or MYH9ΔC570, were unaffected. The effects of MYH9‐siRNA‐induced suppression underline the critical role of NMHC‐IIA in maintenance of cell shape and adhesion. However, the results also indicate that the NMHC‐IIA mutants, R702C and R705H do not inactivate or suppress the endogenous wild type NMHC‐IIA within the HeLa or HEK293 cell assay system. Cell Motil. Cytoskeleton 2008. © 2008 Wiley‐Liss, Inc.
Negative influence of changing biopsy practice patterns on the predictive value of prostate‐specific antigen for cancer detection on prostate biopsy
Authors: Schwartz Michael J. , Hwang David H. , Hung Andrew J. , Han Jullet , McClain Justin W. , Shemtov M. Mendel , Te Alexis E. , Sosa R. Ernest , Vaughan E. Darracott , Scherr Douglas S. 
Published: March 2008

AbstractBACKGROUND.A correlation between prostate specific antigen (PSA) level and positive prostate biopsy rate was established in an era when biopsy practice patterns were different from what they are today. We evaluated if changes in biopsy practice patterns have affected the ability of PSA to predict cancer detection on prostate biopsy in the current era.METHODS.Of 3634 prostate biopsies performed from 1993–2005, 1607 met criteria for analysis. Biopsy data were divided into 3 time‐cohorts (1993–1997, 1998–2001, and 2002–2005) to assess for practice patterns shifts and correlation between PSA and biopsy results.RESULTS.Significant changes in biopsy practice patterns included an increase in biopsy cores and more frequent use of PSA 2.5–3.99 ng/mL as a biopsy indication. In men with normal DRE, a moderate correlation between PSA and positive biopsy rate did exist from 1993–1997, but was subsequently lost. On multivariate analysis, PSA was not a significant predictor of biopsy result in men with normal DRE.CONCLUSIONS.Early in the PSA era, the predictive power of PSA depended on multiple factors: high prevalence of disease, higher prevalence of high‐grade disease, and low likelihood of prostate cancer diagnosis in men with low PSA. Now, beyond the culling effect of increased biopsy incidence and with shifted biopsy practice patterns, the correlation between PSA and biopsy result is lost in men with normal DRE. Diagnosing a higher proportion of tumors in men with a PSA between 2.0–4.0 ng/mL has negatively influenced the predictive value of PSA for cancer detection. Cancer 2008. © 2008 American Cancer Society.
Ontogeny of vasotocin‐expressing cells in zebrafish: Selective requirement for the transcriptional regulators orthopedia and single‐minded 1 in the preoptic area
Authors: Eaton Jennifer L. , Holmqvist Bo , Glasgow Eric 
Published: March 2008

AbstractThe neurohypophysial peptide arginine vasotocin, and its mammalian ortholog arginine vasopressin, influence a wide range of physiological and behavioral responses, including aspects of sexual and social behaviors, osmoregulation, stress response, metabolism, blood pressure, and circadian rhythms. Here, we demonstrate that, in zebrafish (Danio rerio), the vasotocin precursor gene arginine vasotocin‐neurophysin (avt) is expressed in two domains in the developing embryo: the dorsal preoptic area and the ventral hypothalamus. In the dorsal preoptic area, avt‐expressing cells are intermingled with isotocin‐neurophysin (ist) ‐expressing cells, and these neurons project to the neurohypophysis (posterior pituitary). In the dorsal preoptic area, the transcriptional regulators orthopedia b (otpb) and simple‐minded 1 (sim1) are required for expression of both avt and ist. In contrast, otp and sim1 are not required for avt expression in the ventral hypothalamus. Thus, the development of these two avt expression domains is influenced by separate gene regulatory networks. Developmental Dynamics 237:995–1005, 2008. © 2008 Wiley‐Liss, Inc.
Reactions of Terphenylbismuth Dihalides with KSi(SiMe3)3, K2Si2(SiMe3)4 and Na2[Fe(CO)]4: Reduction vs. Metathesis
Authors: Wolf Robert , Fischer Jelena , Fischer Roland C. , Fettinger James C. , Power Philip P. 
Published: March 2008

AbstractThe reactions of terphenylbismuth dihalides with various reducing agents were investigated. Attempted metathesis of Ar′BiCl2 [Ar′ = 2,6‐(2,6‐iPr2‐C6H3)2‐C6H3] with one equivalent of KSi(SiMe3)3 gave the 1,2‐dichlorodibismuthane Ar′(Cl)Bi–Bi(Cl)Ar′ (1) in 40 % yield. The reaction of Ar′BiCl2 (1) with the dianionic salt K2Si2(SiMe3)4 yielded the dibismuthene Ar′Bi=BiAr′ (2) in 72 %. The terphenylbismuth dihalides ArBiCl2 [Ar = 2,6‐(2,6‐iPr2‐C6H3)2‐C6H3 (Ar′), 2,6‐(2,4,6‐Me3‐C6H2)2‐C6H3 (Ar#)] were treated with Na2[Fe(CO)4] in THF to afford the iron dibismuthene complexes [Fe(CO)4(Bi2Ar′2)] (3) and [Fe(CO)4(Bi2Ar#2)] (4) in modest yields (25 and 15 % respectively). The compounds 1–4 were characterized by X‐ray crystallography and by spectroscopic methods (1H and 13C NMR, IR, and UV/Vis spectroscopy). The results show that reduction of the bismuth center is strongly preferred over salt metathesis chemistry due to the reducing power of the silanide and ferrate salts and the strength of the Bi=Bi bond. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)