bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of single‐ and multiple‐stranded cystine‐rich peptides
Authors: Moroder Luis , Musiol Hans‐Jürgen , Götz Marion , Renner Christian 
Published: December 2004

AbstractThe large abundance of bioactive single‐ and multiple‐stranded cystine‐rich peptides in nature has fostered the development of orthogonal thiol‐protection schemes and of efficient chemistries for regioselective disulfide formation in synthetic replica for decades. In parallel to these entirely synthetic strategies, an increased knowledge of oxidative refolding mechanisms of proteins has been accumulated, and the collective experience with air oxidation of cysteine‐rich peptides into their native disulfide frameworks have largely confirmed Anfinsen′s principle of the self‐assembly of polypeptide chains. In fact, a continuously growing number of cysteine‐rich bioactive peptides from the most diverse sources and with differing cysteine patterns were found to retain the critical sequence‐encoded structural information for correct oxidative folding into the native structures as dominant isomers, although in the biosynthetic pathways the mature peptide forms are mostly generated by posttranslational processing of folded precursors. Such self‐assembly processes can be optimized by opportune manipulation of the experimental conditions or by induction of productive intermediates. But there are also numerous cases where folding and disulfide formation are thermodynamically not coupled and where the application of a defined succession of regioselective cysteine pairings still represents the method of choice to install the desired native or non‐native cystine frameworks. Among our contributions to the state of the art in the synthesis of cystine‐rich peptides, we have mainly addressed the induction of correct oxidative refolding of single‐stranded cysteine‐rich peptides into their native structures by the use of selenocysteine and suitable strategies for disulfide‐mediated assembly of monomers into defined oligomers as mimics of homo‐ and heterotrimeric collagens as a synthetic approach for the development of new biomaterials. © 2004 Wiley Periodicals, Inc. Biopolymers (Pept Sci), 2005
Turn stabilization in short peptides by Cα‐methylated α‐amino acids
Authors: Crisma Marco , Moretto Alessandro , De Zotti Marta , Formaggio Fernando , Kaptein Bernard , Broxterman Quirinus B. , Toniolo Claudio 
Published: December 2004

AbstractThe crystal‐state conformations of three protected tripeptides, four tetrapeptides, and one pentapeptide, heavily based on the chiral Cα‐methylated α‐amino acids Iva, (αMe)Nva, and (Me)Val, were assessed by X‐ray diffraction analyses. The eight peptide sequences are as follows: Z(DIva)2DValOMe, ZDIvaLIvaGlyOtBu, ZLProDIvaLIvaGlyOtBu, ZLProLIvaDIvaGlyOtBu, ZAib[L(αMe)Nva]2OtBu, Ac[L(αMe)Val]3D(αMe)ValOtBu, Z[L(αMe)Val]4OH, and ZLAla[L(αMe)Nva]4OtBu. Two independent molecules were observed in the asymmetric units of ZDIvaLIvaGlyOtBu and ZAib[L(αMe)Nva]2OtBu, while three independent molecules were seen in ZLAla[L(αMe)Nva]4OtBu. All peptides are folded in a single or multiple β‐turn conformations. Interestingly: (i) a water bridge within the N‐terminal β‐turn is seen in ZLProLIvaDIvaGlyOtBu (dihydrate), and (ii) the hydroxyl group of the C‐terminal carboxyl functionality of Z[L(αMe)Val]4OH generates an oxy‐analogue of a β‐turn. The N‐terminal β‐turn is missing in molecules A and B, but it does occur, although poorly stabilized, in molecule C, of ZLAla[L(αMe)Nva]4OtBu. © 2004 Wiley Periodicals, Inc. Biopolymers (Pept Sci), 2005
Asymmetric Diethyl‐ and Diphenylzinc Additions to Aldehydes by Using a Fluorine‐Containing Chiral Amino Alcohol: A Striking Temperature Effect on the Enantioselectivity, a Minimal Amino Alcohol Loading, and an Efficient Recycling of the Amino Alcohol
Authors: Park Jin Kyoon , Lee Hong Geun , Bolm Carsten , Kim B. Moon 
Published: December 2004

AbstractA chiral pyrrolidinylmethanol derivative containing perfluoro‐ponytails (5) was prepared from (S)‐proline. The use of this perfluoro‐substituted amino alcohol in catalytic asymmetric additions of organozinc reagents to aldehydes affords products with high enantioselectivities in both pure hexane and a mixture of hexane and FC‐72 (perfluorohexane). Enantiomeric excesses up to 94 and 88 % ee have been achieved in Et2Zn and Ph2Zn additions, respectively. For the reactions in the biphasic solvent system a striking temperature effect was observed. Thus, when the temperature was raised from 0 to 40 °C the ee value of the product increased from 81 to 92 %. Furthermore, the catalyst loading could be remarkably low, and with only 0.1 mol % of amino alcohol 5 a product with 90 % ee was obtained in the Et2Zn addition to benzaldehyde in hexane. The perfluoro‐ligand was easily recovered by simple phase separation, and until the ninth repetition its reuse proceeded without significant loss of enantioselectivity and reactivity.
Titanium‐Based Molecular Squares and Rectangles: Syntheses by Self‐Assembly Reactions of Titanocene Fragments and Aromatic N‐Heterocycles
Authors: Kraft Susanne , Hanuschek Edith , Beckhaus Rüdiger , Haase Detlev , Saak Wolfgang 
Published: December 2004

AbstractThis paper reports on the potential of titanium compounds as building blocks for supramolecular polygons. Self‐assembly reactions of low‐valent titanocene units and N‐heterocyclic bridging ligands lead to novel titanium‐based supramolecular squares. Pyrazine (3), 4,4′‐bipyridine (4), and tetrazine (5) were used as bridging ligands, and the acetylene complexes [Cp2Ti{η2‐C2(SiMe3)2}] (1) and [(tBuCp)2Ti{η2‐C2(SiMe3)2}] (2) as sources of titanocene fragments. Molecular rectangles can be synthesized by stepwise reduction of the titanocene dichlorides [Cp2TiCl2] and [(tBuCp)2TiCl2] and consecutive coordination of two different bridging ligands. The resulting complexes are the first examples of molecular rectangles containing bent metallocene corner units. Single‐crystal X‐ray analyses of the tetranuclear compounds revealed the geometric properties of the molecular polygons in the solid state. Comparison of bond lengths and angles in coordinated and free ligands reveals the reduced state of the bridging ligand in the low‐valent titanium compounds. The syntheses and properties of these novel, highly air‐ and moisture‐sensitive compounds are discussed.
Phase II study of irinotecan (CPT‐11) as salvage therapy for advanced nasopharyngeal carcinoma
Authors: Poon Donald , Chowbay Balram , Cheung Yin‐Bun , Leong Swan‐Swan , Tan Eng‐Huat 
Published: December 2004

AbstractBACKGROUNDThis Phase II study was designed to evaluate the efficacy and safety of irinotecan in patients with advanced nasopharyngeal carcinoma (NPC).METHODSPatients with disseminated, undifferentiated NPC that progressed during or within 3 months of platinum‐based and/or taxane‐based regimen were eligible. Irinotecan at a dose of 100 mg/m2 was administered on Days 1, 8, and 15 every 28 days, up to a maximum of 6 cycles, until disease progression or the appearance of intolerable toxicity.RESULTSTwenty‐eight patients were evaluable for toxicity and response. Patient characteristics were as follows: The median age was 46.5 years (range, 40.3–71.6 years), the median number of prior lines of chemotherapy was 2 (range, 1–9), the majority of patients (89%) had good Eastern Cooperative Oncology Group performance status (0–1), and the majority of patients (82.1%) had ≥ 2 sites of distant metastases. A total of 79 cycles of irinotecan with a median of 3 cycles per patient were administered. Toxicity > Grade 3 included neutropenia in 5 patients (17%), anemia in 5 patients (17%), and diarrhea in 4 patients (14%). The best response outcomes were 4 patients (14%) who achieved partial responses and 1 patient (4%) who achieved stable disease. Global quality‐of‐life scores were stable during treatment. Using the Kaplan–Meier method, the median progression‐free survival was 3.9 months, and the median overall survival was 11.4 months. The partial responders had a durable response (range, 5.7–12.2 months).CONCLUSIONSResults from this trial suggest that irinotecan is an active salvage agent with modest toxicity in patients with advanced NPC who are refractory to platinum/taxane‐based chemotherapy. Studies combining irinotecan with other active agents in the first‐line setting are warranted. Cancer 2005. © 2004 American Cancer Society.
Predicting psychological morbidity in Chinese women after surgery for breast carcinoma
Authors: Lam Wendy W. T. , Fielding Richard , Ho Ella Y. Y. 
Published: December 2004

AbstractBACKGROUNDBetween 30% and 70% of western women experience psychological morbidity after undergoing surgery for breast carcinoma; however, the rates and risk factors among Chinese women are unknown. Identifying at‐risk women enables preventive intervention.METHODSAmong 430 Chinese women who were approached within 1 week after undergoing surgery for early‐stage breast carcinoma (baseline), 405 women (94%) completed measures of self‐efficacy and psychological morbidity (the Chinese Health Questionnaire 12‐item instrument [CHQ12]) and completed retrospective measures of treatment decision‐making (TDM) difficulties, satisfaction with TDM involvement, and satisfaction with consultation and treatment outcome expectations. One‐month postsurgery follow‐up (follow‐up), CHQ12 scores for 367 of 405 women (91%) were adjusted for concurrent physical symptom distress and trait optimism (the revised Chinese Life Orientation Test) and baseline predictors using stepwise multivariate regression.RESULTSAt baseline 28% of women evidenced mild psychological morbidity, and 42% of women evidenced moderate‐to‐severe psychological morbidity: At follow‐up, the respective rates were 32% and 36%. Preferred TDM involvement was associated with lower psychological morbidity (F = 6.702;P< 0.001). Baseline CHQ12 scores were predicted by outcome expectancies and TDM difficulties (adjusted regression coefficient [R2] = 0.192). Baseline CHQ12 scores and follow‐up chemotherapy, in turn, predicted physical symptom distress at follow‐up. After adjustment, high physical symptom distress, baseline psychological morbidity, low optimism, and no chemotherapy independently predicted follow‐up CHQ12 scores (adjusted R2= 0.585).CONCLUSIONSPsychological morbidity was linked to women's TDM difficulties, their inability to anticipate treatment effects accurately, and physical symptom distress, possibly exacerbated by symptom misattribution. Optimizing TDM support and helping women accurately determine outcomes in terms of symptom experience and meaning and physical appearance may help to reduce psychological morbidity. Women who have TDM difficulties should be considered to be at high risk for psychological distress. Cancer 2005. © 2004 American Cancer Society.
Overexpression of macrophage migration inhibitory factor induces angiogenesis and deteriorates prognosis after radical resection for hepatocellular carcinoma
Authors: Hira Eiji , Ono Takashi , Dhar Dipok Kumar , El‐Assal Osama N. , Hishikawa Yoshitaka , Yamanoi Akira , Nagasue Naofumi 
Published: December 2004

AbstractBACKGROUNDMacrophage migration inhibitory factor (MIF) is a pivotal cytokine that regulates inflammatory and immune responses. Recently, many investigators reported that MIF is expressed highly in several tumors, including hepatocellular carcinoma (HCC). However, the role of MIF in tumor angiogenesis and patient prognosis has not been examined in patients with HCC.METHODSThe authors evaluated MIF expression in 56 samples of HCC by Western blot analysis, and the results were correlated with clinicopathologic factors and patient prognosis. MIF localization was determined by immunohistochemical methods, and the results were compared with tumor microvessel density (MVD), as assessed by anti‐CD34 antibody. Furthermore, to validate the role of MIF in angiogenesis, both MIF expression during culture of HCC cells (using the Hep3B, HepG2, and Huh7 cell lines) under hypoxic condition and the angiogenic potential of recombinant MIF in an in vitro angiogenic model were examined.RESULTSTumors with high MIF expression had high α‐fetoprotein levels (P = 0.049) and frequent intrahepatic recurrence (P = 0.043). Immunohistochemical MIF scores had a significant correlation with MVD (P = 0.007). Patients who had tumors with high MIF expression levels had a significantly worse (P = 0.025) disease‐free survival, and this finding remained significant as an independent prognostic factor in the multivariate analysis. Hep3B cells had high expression of MIF at 6 hours and 12 hours after hypoxic stress and exogenous MIF stimulated endothelial tube formation in in vitro angiogenesis.CONCLUSIONSThe current findings suggest that MIF expression may play a pivotal role in the dismal prognosis of patients with HCC that may be attributable to the modulation of angiogenesis. Cancer 2005. © 2004 American Cancer Society.
Glycinergic neurons expressing enhanced green fluorescent protein in bacterial artificial chromosome transgenic mice
Authors: Zeilhofer Hanns Ulrich , Studler Barbara , Arabadzisz Dimitrula , Schweizer Claude , Ahmadi Seifollah , Layh Beate , Bösl Michael R. , Fritschy Jean‐Marc 
Published: December 2004

AbstractAlthough glycine is a major inhibitory transmitter in the mammalian CNS, the role of glycinergic neurons in defined neuronal circuits remains ill defined. This is due in part to difficulties in identifying these cells in living slice preparations for electrophysiological recordings and visualizing their axonal projections. To facilitate the morphological and functional analysis of glycinergic neurons, we generated bacterial artificial chromosome (BAC) transgenic mice, which specifically express enhanced green fluorescent protein (EGFP) under the control of the promotor of the glycine transporter (GlyT) 2 gene, which is a reliable marker for glycinergic neurons. Neurons expressing GlyT2‐EGFP were intensely fluorescent, and their dendrites and axons could be visualized in great detail. Numerous positive neurons were detected in the spinal cord, brainstem, and cerebellum. The hypothalamus, intralaminar nuclei of the thalamus, and basal forebrain also received a dense GlyT2‐EGFP innervation, whereas in the olfactory bulb, striatum, neocortex, hippocampus, and amygdala positive fibers were much less abundant. No GlyT2‐EGFP‐positive cell bodies were seen in the forebrain. On the subcellular level, GlyT2‐EGFP fluorescence was colocalized extensively with glycine immunoreactivity in somata and dendrites and with both glycine and GlyT2 immunoreactivity in axon terminals, as shown by triple staining at all levels of the neuraxis, confirming the selective expression of the transgene in glycinergic neurons. In slice preparations of the spinal cord, no difference between the functional properties of EGFP‐positive and negative neurons could be detected, confirming the utility of visually identifying glycinergic neurons to investigate their functional role in electrophysiological studies. J. Comp. Neurol. 482:123–141, 2005. © 2004 Wiley‐Liss, Inc.
Gap‐junction communication between subtypes of direction‐selective ganglion cells in the developing retina
Authors: DeBoer Darrell J. , Vaney David I. 
Published: December 2004

AbstractThe On‐Off direction‐selective ganglion cells (DSGCs) in the rabbit retina comprise four distinct subtypes that respond preferentially to image motion in four orthogonal directions; each subtype forms a regular territorial array, which is overlapped by the other three arrays. In this study, ganglion cells in the developing retina were injected with Neurobiotin, a gap‐junction‐permeable tracer, and the DSGCs were identified by their characteristic type 1 bistratified (BiS1) morphology. The complex patterns of tracer coupling shown by the BiS1 ganglion cells changed systematically during the course of postnatal development. BiS1 cells appear to be coupled together around the time of birth, but, over the next 10 days, BiS1 cells decouple from each other, leading to the mature pattern in which only one subtype is coupled. At about postnatal day 5, before the ganglion cells become visually responsive, each of the BiS1 cells commonly showed tracer coupling both to a regular array of neighboring BiS1 cells, presumably destined to be DSGCs of the same subtype, and to a regular array of overlapping BiS1 cells, presumably destined to be DSGCs of a different subtype. The gap‐junction intercellular communication between subtypes of DSGCs with different preferred directions may play an important role in the differentiation of their synaptic connectivity, with respect to either the inputs that DSGCs receive from retinal interneurons or the outputs that DSGCs make to geniculate neurons. J. Comp. Neurol. 482:85–93, 2005. © 2004 Wiley‐Liss, Inc.
ϵ‐Sarcoglycan immunoreactivity and mRNA expression in mouse brain
Authors: Chan Pokman , Gonzalez‐Maeso Javier , Ruf Frédérique , Bishop David F. , Hof Patrick R. , Sealfon Stuart C. 
Published: December 2004

AbstractMyoclonus dystonia (M‐D) is a hereditary movement disorder caused by a maternally imprinted gene that is often associated with psychiatric symptoms. Most cases of M‐D are believed to result from mutations of the ϵ‐sarcoglycan protein. The neuroanatomical distribution of ϵ‐sarcoglycan‐like immunoreactivity in mouse was investigated by using an antiserum against the ϵ‐sarcoglycan protein. The expression of ϵ‐sarcoglycan mRNA was studied by a sensitive fluorescence in situ hybridization (FISH) method. Immunohistochemistry and FISH revealed a wide distribution of ϵ‐sarcoglycan protein and mRNA throughout the mouse brain. High expression levels of ϵ‐sarcoglycan mRNA and immunoreactivity were found in the mitral cell layer of the olfactory bulb, the Purkinje cell layer in cerebellum, and the monoaminergic neurons in the mouse midbrain. Immunohistochemistry revealed a similar distribution of ϵ‐sarcoglycan protein. Double‐labeling FISH showed colocalization of tyrosine hydroxylase and ϵ‐sarcoglycan mRNAs within all the midbrain dopaminergic (DAergic) cell groups. By combining FISH with fluorescence immunohistochemistry, coexpression of ϵ‐sarcoglycan mRNA and tryptophan hydroxylase immunoreactivity was found in the serotonergic (5‐HTergic) neurons within the dorsal raphe nucleus. The distribution of ϵ‐sarcoglycan in the mouse brain suggests that the symptom complex of M‐D may be related to the effects of decreased ϵ‐sarcoglycan activity on the development or function of monoaminergic neurons. J. Comp. Neurol. 482:50–73, 2005. © 2004 Wiley‐Liss, Inc.
Distinct expression pattern of insulin‐like growth factor family in rodent taste buds
Authors: Suzuki Yuko , Takeda Masako , Sakakura Yasunori , Suzuki Noriyo 
Published: December 2004

AbstractThe insulin‐like growth factor (IGF) system is an important regulator of growth and differentiation in a variety of tissues. In the present study, the expression of IGF family members in the taste buds of mice and rats was examined. By reverse transcriptase polymerase chain reaction (RT‐PCR) analysis, mRNA of IGF‐I and ‐II, IGF‐I receptor (IGF‐IR), insulin receptor (insulin R), and IGF‐binding protein (IGFBP)‐2, ‐3, ‐4, ‐5, and ‐6 was detected in the taste bud‐containing epithelium of the circumvallate papillae of mice. As suggested by the study using degenerate PCR (McLaughlin [2000] J. Neurosci. 20:5679–5688), IGF‐IR was expressed in most of the taste bud cells of adult mice, as found by immunohistochemistry, and in those of postnatal day (P) 6 mice by in situ hybridization. Insulin R, which has strong homology to IGF‐IR, was also detected in most of the taste bud cells of mice by immunohistochemistry and in situ hybridization. IGF‐I immunoreactivity was detected in a few taste bud cells and in the epithelium surrounding taste buds. Northern blot analysis revealed that the amount of IGF‐I mRNA in taste bud‐containing epithelium was very low compared with that in liver. IGF‐II immunoreactivity was weakly detected in mouse taste buds and the surrounding epithelium. In the rat tissue, a subset of the taste bud cells was positive for IGF‐II. Among the six IGFBPs, IGFBP‐2, ‐5, and ‐6 were detected in the mouse taste buds: IGFBP‐2 and ‐5 immunoreactivity was seen in the majority of the taste bud cells, whereas IGFBP‐6 immunoreactivity was found in the nerve fibers innervating the taste buds. In situ hybridization study also revealed that IGFBP‐2 and ‐5 mRNA was synthesized in the taste buds of P6 mice and that the expression of these mRNAs overlapped in von Ebner's glands. These data reveal that IGF‐I and ‐II might be produced in taste bud cells and (or) surrounding lingual epithelium and act through IGF‐IR and insulin R locally in a paracrine and autocrine manner. The activity of these IGFs may be modulated through their interaction with IGFBP‐2, ‐5, and 6. J. Comp. Neurol. 482:74–84, 2005. © 2004 Wiley‐Liss, Inc.
ZFH4 protein is expressed in many neurons of developing rat brain
Authors: Nogami Shigeharu , Ishii Yoko , Kawaguchi Makoto , Sakata Nobuo , Oya Takeshi , Takagawa Kiyoshi , Kanamori Masahiko , Sabit Hemragul , Obata Toshiyuki , Kimura Tomoatsu , Sasahara Masakiyo 
Published: December 2004

AbstractThe zinc finger‐homeodomain (ZFH) transcription factors contain a zinc finger motif and a homeodomain that might regulate neural and mesenchymal cell differentiation. We have cloned the ZFH4 gene that encodes a protein with structures closely related to ATBF1. In order to study the expression pattern of ZFH4 in the developing rat brain, we raised an antibody against a glutathione‐S‐transferase (GST) fusion protein of ZFH4. Western blotting with this antibody identified a gene product of 390 kDa in the normal rat brain. Levels of the protein were high in the brainstem at embryonic and neonatal periods and in the midbrain and diencephalon in neonatal rat brain. In addition, the corresponding mRNA of 12.5 kb was detected by Northern blotting. An immunolocalization study showed that postmitotic neurons in the brainstem were the major site of ZFH4 expression, and the levels of expression varied depending on age and anatomical sites. Expression was transient and weak in precursor cells at early neurogenesis. Although ZFH4 levels decreased after birth, ZFH4 continued to be expressed in the mature neurons including DOPA decarboxylase‐positive neurons. High levels of expression were also detected in non‐neuronal cells of the subcommissural organ, but the expression was almost undetectable throughout precursor cells to mature neurons in the cerebral cortex and hippocampus. The spatial and temporal expression patterns closely resembled those of ATBF1, and we detected neurons that expressed ZFH4, ATBF1, or both. We postulate that ZFH4 participates in the regulation of neural cell maturation or of region‐specific differentiation of the brain. J. Comp. Neurol. 482:33–49, 2005. © 2004 Wiley‐Liss, Inc.