bluuebunny/crossref_metadata_2025_split huggingface dataset:
NMR analysis of 6‐(2′,3′‐dihydro‐1′H‐inden‐1′‐yl)‐1H‐indene
Authors: Spiteller Peter , Spiteller Michael , Jovanovic Jovan 
Published: August 2002

Abstract1H, 13C and two‐dimensional NMR analyses were applied to determine the NMR parameters of 6‐(2′,3′‐dihydro‐1′H‐inden‐1′‐yl)‐1H‐indene. The measurements were accomplished with 0.5 mg of the substance, this quantity being sufficient to determine the chemical shifts of all the H and C atoms, and also the appropriate coupling constants and to give the complete NMR resonance assignments of the molecule. The predicted patterns of the four different H atoms of the methylene groups of the indane structural element coincided completely with the complex patterns in the NMR spectra. Copyright © 2002 John Wiley & Sons, Ltd.
1H and 13C NMR assignments of new oligo‐bipyridine–phenanthroline hybrids as potential precursors of helicate complexes
Authors: Annunziata Rita , Benaglia Maurizio , Bologna Alberto 
Published: August 2002

AbstractA series of oligo‐bipyridine–phenanthroline hybrids, a new class of potential model ligands, were synthesized and their 1H and 13C NMR spectra assigned. Copyright © 2002 John Wiley & Sons, Ltd.
Reassignment of the 1H NMR spectrum of fusidic acid and total assignment of 1H and 13C NMR spectra of some selected fusidane derivatives
Authors: Rastrup‐Andersen Niels , Duvold Tore 
Published: August 2002

AbstractReassignment of the 1H and 13C NMR spectra of fusidic acid and the total assignment of lumifusidic acid and some important di‐ and tetra‐hydrofusidic acid derivatives are reported. Copyright © 2002 John Wiley & Sons, Ltd.
Substituent effects on 1H and 13C NMR chemical shifts in α‐monosubstituted ethyl acetates: principal component analysis and 1H chemical shift calculations
Authors: Tasic Ljubica , Abraham Raymond J. , Rittner Roberto 
Published: August 2002

AbstractA principal component analysis is applied to α‐monosubstituted ethyl acetates (YCH2CO2Et), where the observed chemical shifts for the α‐carbon atom, the carbonyl carbon, and the α‐hydrogen atoms are correlated with theoretically derived molecular properties, i.e. the partial charges on the same atoms and the electronegativity and hardness. The effects on 1H and 13C NMR chemical shifts of 12 α‐substituents: F, Cl, Br, I, OMe, OEt, SMe, SEt, NMe2, NEt2, Me, and Et were investigated. A strong grouping of the same heteroatom substituents is observed, showing the chemical shift dependence on the type of substituent. Halogenated compounds represent a heterogeneous group, where the large effect of the fluorine substituent is similar to that of the oxygen derivatives (OMe and OEt). Theoretical calculations show that fluorine and oxygen derivatives exhibit similar energy curves with respect to the YCCO dihedral angle and the same conformational equilibrium between cis and trans rotamers. Sulfur, neutral substituents and halogen derivatives (Cl, Br and I) give an equilibrium between cis and gauche rotamers, with a predominance of the gauche conformers. The rotational equilibrium in solution was confirmed by 1H chemical shift calculations utilizing the CHARGE 7H program. The calculated α‐hydrogen atom chemical shifts are in very good agreement with the measured values. Copyright © 2002 John Wiley & Sons, Ltd.
Self‐reactivity of s‐triazine and its radical cation: an electron/proton transfer process driven by ionizing radiation
Authors: Rhodes Christopher J. , Moynihan Humphrey A. 
Published: August 2002

AbstractExposure of solutions of s‐triazine in a trichlorofluoromethane matrix at 77 K to γ‐radiation resulted in the formation of s‐triazinyl radicals by deprotonation of the primary radical cations. The results indicate that neutral s‐triazine molecules dissolve in an associated state in the Freon solvent. Copyright © 2001 John Wiley & Sons, Ltd.
Complete assignments of the 1H and 13C NMR spectra of six highly functionalized neoclerodane diterpenoids
Authors: Rodríguez Benjamín 
Published: August 2002

AbstractAn NMR study of six highly functionalized neoclerodane diterpenes belonging to both A/B cis and trans series is described. In addition to 1D NMR methods, 2D shift‐correlated experiments [1H,1H‐COSY, 1H,1H‐TOCSY, 1H,13C‐gHSQC‐1J(C,H), 1H,13C‐gHMBC‐nJ(C,H) (n = 2 and 3)] and 2D 1H,1H‐NOESY were used for the complete and unambiguous 1H and 13C chemical shift assignments of these structurally complex diterpenoids. Copyright © 2001 John Wiley & Sons, Ltd.
1H and 13C NMR conformational study of N‐substituted hexahydrocyclopent[e][1,3]‐oxazin‐4‐ones and hexahydro‐2H‐1,3‐benzoxazin‐4‐ones
Authors: Shaikhutdinov Roustem A. , Klika Karel D. , Fülöp Ferenc , Pihlaja Kalevi 
Published: August 2002

AbstractA 1H and 13C NMR conformational study of four cis‐fused N‐substituted hexahydrocyclopent[e][1,3]oxazin‐4‐ones and four cis‐fused hexahydro‐2H‐1,3‐benzoxazin‐4‐ones at various temperatures revealed several dynamic conformational processes to be in effect. These included a clear conformational equilibrium between the O‐in (major conformer) and O‐out ring forms in the hexahydro‐2H‐1,3‐benzoxazin‐4‐ones, an equilibrium consisting of two intramolecularly hydrogen bonded forms (between the hydroxyl proton and the carbonyl oxygen attached to C4 or the ethereal oxygen) and a non‐hydrogen bonded form in two compounds, and a restricted rotation about the amide C N bond in the CH2OCONHC6H4X‐p substituents (X = H, Cl) in three other compounds. Copyright © 2001 John Wiley & Sons, Ltd.
13C CP/MAS NMR studies of flavonoids
Authors: Wawer Iwona , Zielinska Agnieszka 
Published: August 2002

Abstract13C CP/MAS NMR spectra were recorded to characterize the solid‐state conformation of flavonoids: galangin, kaempferol, quercetin, myricetin, chrysin, apigenin, luteolin, acacetin, hesperetin and naringenin. Correct assignment of the signals in solution‐state spectra (using APT, HSQC and HMBC) and solid‐state spectra (using dipolar dephased and short contact sequences) for the above flavonoids is reported. The locked conformation of OH and OCH3 groups in solids results in an increased shielding of carbon adjacent to C—OH or C—OCH3 hydrogens, enabling conclusions as to the orientations of these groups to be drawn. The C‐5—OH hydroxyl (and C‐3—OH) points towards the carbonyl group oxygen, forming intramolecular hydrogen bonds. Considerations of C2′ and C6′ carbon shielding suggest that ring B is not coplanar with the benzopyran fragment in kaempferol, acacetin and myricetin. Copyright © 2001 John Wiley & Sons, Ltd.
C—H···X (X = N, O, S) intramolecular interaction in 1‐vinyl‐2‐(2′‐heteroaryl)pyrroles as monitored by 1H and 13C NMR spectroscopy
Authors: Afonin Andrei V. , Ushakov Igor A. , Kuznetsova Svetlana Yu. , Petrova Ol'ga V. , Schmidt Elena Yu. , Mikhaleva Al'bina I. 
Published: August 2002

Abstract1H and 13C NMR spectroscopy of a series of 1‐vinyl‐2‐(2′‐heteroaryl)‐pyrroles were employed for the analysis of their electronic and spatial structure. The C—H···N intramolecular interaction between the α‐hydrogen of the vinyl group and the pyridine nitrogen, a kind of hydrogen bonding, was detected in 1‐vinyl‐2‐(2′‐pyridyl)pyrrole, which disappeared in its iodide methyl derivative. It was shown that this interaction is stronger than the C—H···O and C—H···S interactions in 1‐vinyl‐2‐(2′‐furyl)‐ and ‐2‐(2′‐thienyl)‐pyrroles. Copyright © 2001 John Wiley & Sons, Ltd.
A novel seminal plasma glycoprotein of a teleost, the nile tilapia (Oreochromis niloticus), contains a partial von Willebrand factor type D domain and a zona pellucida‐like domain
Authors: Mochida Kazuhiko , Matsubara Takahiro , Andoh Tadashi , Ura Kazuhiro , Adachi Shinji , Yamauchi Kohei 
Published: August 2002

AbstractOur previous study shows that seminal plasma of a teleost, the Nile tilapia, contains a glycoprotein Mr = 120,000 named as SPP (Seminal plasma glycoprotein)120 which forms a homopolymer that has sperm immobilizing activity. In order to elucidate the mechanisms of the formation of the homopolymer and the immobilization of sperm, molecular cloning of SPP120 was conducted. The cDNA for SPP120 contains a complete open reading frame encoding 797 amino acid residues with 14 potential N‐glycosylation sites. The predicted amino acid sequence of SPP120 contains a partial von Willebrand factor type D domain and a zona pellucida domain, that are involved in protein–protein adhesion that form filamentous structures in various kinds of cells. This result suggests that SPP120 forms a homopolymer via these domains in seminal plasma and probably interacts with spermatozoa. Northern blotting reveals that the gene is also expressed in ovary, even in ovulated eggs. The results of in situ hybridization indicate that in testis the gene is expressed in Sertoli cells and epithelial cells of sperm ducts, and the localization corresponds to that of the protein analyzed by immunohistochemistry. In the ovary, the gene is expressed at the perinucleolus stage of oocytes; however, the protein is not detected in any cells other than oocytes. Mol. Reprod. Dev. 62: 57‐68, 2002. © 2002 Wiley‐Liss, Inc.
Expression of matrix metalloproteinase ‐2, ‐9 and tissue inhibitors of metalloproteinase ‐1, ‐2, ‐3 mRNAs in rat uterus during early pregnancy
Authors: Zhao Yun‐Ge , Xiao Ai‐Zhen , Cao Xiu‐Mei , Zhu Cheng 
Published: August 2002

AbstractZymography and in situ hybridizition were used to investigate matrix metalloproteinase‐2, ‐9 (MMP‐2, ‐9) activities, and expression of mRNAs for MMP‐2, ‐9 and tissue inhibitors of matrix metalloproteinases (TIMP‐1, ‐2, ‐3) in the rat uterus during early pregnancy (day 1–7). The zymography results showed two forms of MMP‐2 (64 and 67 kDa) in the rat uteri during early pregnancy. The 64‐kDa MMP‐2 activity was the highest on day 2 (P < 0.01) and higher on day 5 and 6 (P < 0.05). The 67‐kDa MMP‐2 activity reached the highest on day 5 and 6 (P < 0.01). The 64‐kDa MMP‐2 activity at the implantation sites was higher than those at interimplantation sites (P < 0.05). Furthermore, the 67 kDa MMP‐2 can be converted to 64 kDa forms by incubation with p‐aminophenylmercuric acetate (APMA) and trypsin in vitro. The 92‐kDa MMP‐9 activity was only detected on day 5 and 6 of pregnancy (P < 0.01). In situ hybridization showed that on day 1–4 of pregnancy, both MMP‐2 and TIMP‐2 mRNAs were evidently localized in the basal stromal cells. On day 5, MMP‐2 mRNA signals were decreased in the basal stromal cells and mRNA for TIMP‐2 was expressed in the epithelial cells and subepithelial stromal cells. The mRNAs for MMP‐9, TIMP‐1, and ‐3 were mainly expressed in epithelial cells on day 1–5. At the implantation site on day 6, the mRNAs for MMP‐2, ‐9, TIMP‐1, ‐2, and ‐3 were highly expressed in the primary decidual zone surrounding the implanting embryo, and in the whole decidualized stromal cells (the primary and secondary decidual zones) at the implantation site on day 7. The intensities of mRNAs for the TIMPs in decidualized stromal cells at the implantation site on day 6 and 7 were stronger than those for the MMPs. The weak mRNAs for MMP‐2, ‐9, TIMP‐1, and ‐3 but not TIMP‐2 were also observed in the ectoplacental cone/trophoblastic cells of the implanting embryos. However, at the interimplantation sites on day 6 and 7, MMP‐2, ‐9, TIMP‐1, ‐2, and ‐3 mRNAs were weakly expressed in the epithelial cells, subepithelial stromal cells, and myometrium. The results suggested that the implanting rat embryo strongly induced MMP‐2 and ‐9 proteins and gene expression for decidulization and embryo invasion, which were strictly controlled and balanced by the simultaneous expression of TIMP‐1, ‐2 and ‐3. Mol. Reprod. Dev. 62: 149–158, 2002. © 2002 Wiley‐Liss, Inc.
Spermatid manchette: Plugging proteins to zero into the sperm tail
Authors: Kierszenbaum Abraham L. 
Published: August 2002

AbstractSpermiogenesis pursues three major objectives: (1) The safeguard of the male genome within the confines of a compact nucleus. (2) The accumulation of enzymes in the acrosome of be released at fertilization. (3) The development of a sperm propelling tail consisting of an axoneme surrounded by a scaffold of keratin‐containing outer dense fibers and a fibrous sheath. Recent experimental data indicate that three keratins‐Sak57, 0df1 and 0df2‐and other proteins (the 26S proteasome and the 0df1‐binding protein Spag4) are temporarily stored in the manchette before being sorted to the developing sperm tail. These findings support a general model for the manchette as an ephemeral structure timely developed and strategically positioned to provide a transient storage to both structural and signaling proteins. Some of the proteins are later sorted to the developing tail; others may participate in the reciprocal nuclear‐cytoplasmic signaling pathways as the gene activity of the male genome gradually becomes silent. Mol. Reprod. Dev. 59: 347–349, 2001. © 2001 Wiley‐Liss, Inc.
Identification and characterization of P31m, a novel sperm protein in Cynomolgus monkey (Macaca fascicularis)
Authors: Lamontagne Nathalie , Légaré Christine , Gaudreault Christian , Sullivan Robert 
Published: August 2002

AbstractWe have previously described a hamster sperm glycoprotein, P26h, which is implicated in the cascade of events occurring during the interaction between mature spermatozoa and the oocyte's zona pellucida. The P26h is acquired on the acrosomal cap of the spermatozoon during its maturation arising within the epididymis. Lately, using a polyclonal antiserum raised against P26h, a 34 kDa protein, P34H, has been identified on the acrosomal cap of the human spermatozoon. The cloning and sequencing of the cDNA encoding P34H has revealed a 65% similarity between the P34H and P26h amino acid sequences. Considering that P26h shows total immunocontraceptive properties in the hamster, it is of relevant importance to have an animal model phylogenetically closer to the human. Using the Cynomolgus monkey, we searched for a protein autologous to the human P34H. A 31 kDa protein, the P31m, localized on the acrosomal cap of the monkey spermatozoon has been identified by a Western blot analysis and by immunohistochemical techniques using an anti‐hamster P26h antiserum. Northern blot analysis showed increasing high levels of the P31m mRNA through the epididymis and at lower levels in the testis. In situ hybridization showed the presence of the P31m mRNA in the principal cells of the epididymis. The cloning and sequencing of the cDNA encoding the P31m showed a high homology of 97% identity between the P31m and P34H nucleotidic sequences. This study clearly demonstrates that the monkey P31m is the homologous protein of the hamster P26h and of the human P34H. Mol. Reprod. Dev. 59: 431–441, 2001. © 2001 Wiley‐Liss, Inc.
Novel human testis‐specific cDNA: Molecular cloning, expression and immunobiological effects of the recombinant protein
Authors: Santhanam Ramasamy , Naz Rajesh K. 
Published: August 2002

AbstractA differential display‐polymerase chain reaction was employed to obtain a testis‐specific cDNA fragment. On screening the human testis‐λgt10‐cDNA library with testis‐specific cDNA fragment, a novel cDNA encoding for a sperm antigen, designated TSA‐1, was obtained. It has a novel open reading frame (ORF) of 471 base pairs encoding for 156 amino acids. The computer generated translated protein has a calculated molecular mass of 17.4 kDa and contains a potential N‐glycosylation site at amino acids 122–124. The hydrophilicity analysis of the amino acid sequence suggested that this protein is a membrane‐anchored peptide. Extensive analysis for tissue‐specificity by Northern blots and RT‐PCR‐Southern blot procedures using various human tissues indicated that TSA‐1 was specifically expressed only in the human testis. Based on the results of in vitro transcription and translation experiments, the TSA‐1 (ORF) was subcloned into pGEX‐6P‐3 vector and expressed using the glutathione S‐transferase gene fusion system. Antibodies (Ab) against the purified recombinant protein specifically recognized the ∼17 kDa recombinant TSA‐1, and a ∼24 kDa band in human sperm extract in the Western blot procedure. The recombinant TSA‐1 Ab recognized the acrosomal, equatorial, mid‐piece, and tail regions of human sperm cell in indirect immunofluorescence, bound to live human sperm in the immunobeads binding technique (IBT) and caused a significant concentration‐dependent inhibition of human sperm acrosome reaction. These findings indicate that the novel sperm‐specific recombinant TSA‐1 has a role in sperm function and may have applications in the development of a contraceptive vaccine, and in the specific diagnosis and treatment of male infertility. Mol. Reprod. Dev. 60: 1–12, 2001. © 2001 Wiley‐Liss, Inc.
Surface of human sperm bears three differently charged CD52 forms, two of which remain stably bound to sperm after capacitation
Authors: Giovampaola C. Della , Flori F. , Sabatini L. , Incerti L. , La Sala G.B. , Rosati F. , Focarelli R. 
Published: August 2002

Abstractgp20 is a sialoglycoprotein of the human sperm surface with a core peptide homologous to the leukocyte antigen CD52, a GPI‐anchored glycosylated protein which is described by the monoclonal antibody CAMPATH‐1. Comparative analyses, by means of CAMPATH and anti‐gp20, indicated that they describe it in morphologically and functionally different ways, suggesting that the respective epitopes are different but also casting doubt on the immunological identity of the antigen. In the present study, we used immunodepletion to demonstrate that CAMPATH and anti‐gp20 interact with the same antigen, but that anti‐gp20 has a much higher avidity for the antigen than CAMPATH. Anion exchange fractionation analysis of the antigen revealed three differently charged gp20‐CD52 forms, the least charged of which, was largely without a GPI‐anchor. All three forms were associated with freshly ejaculated sperm, whereas capacitated sperm only contained the two GPI‐anchored, more charged forms, which were also the ones found in the prostasome fraction of seminal plasma and in leukocytes. The two charged, GPI‐anchored forms were described as homogeneous by anti‐gp20, since they ran as a singlet; the third form ran as a doublet. When tested for insertion into Jurkat T cells, the medium charged form inserted the most readily and the less charged one could not be inserted at all. Mol. Reprod. Dev. 60: 89–96, 2001. © 2001 Wiley‐Liss, Inc.
Expression and action of hepatocyte growth factor in bovine endometrial stromal and epithelial cells in vitro*
Authors: Murakami Shuko , Miyamoto Yoko , Fujiwara Chikako , Takeuchi Sakae , Takahashi Sumio , Okuda Kiyoshi 
Published: August 2002

AbstractHepatocyte growth factor (HGF) is a pleiotropic growth factor that acts on various epithelial cells. The objectives of this study were to determine whether HGF altered the proliferation and prostaglandin (PG) secretion of bovine endometrial stromal and epithelial cells in vitro. We also observed HGF and HGF receptor (c‐met) mRNA expression in cultured bovine endometrial stromal and epithelial cells by RT‐PCR. Stromal and epithelial cells obtained from cows in early stage of the estrous cycle (days 2–5) were cultured in DMEM/Ham's F‐12 supplemented with 10% calf serum. The cells were exposed to HGF (0–10 ng/ml) for 2, 4, or 6 days. HGF significantly increased the total DNA in epithelial (P < 0.05), but not stromal cells. In another experiment, when the cells reached confluence, the culture medium was replaced with fresh medium with 0.1% BSA containing HGF 0–100 ng/ml and the cells were cultured for 24 hr. The HGF stimulated PGF2α secretion in epithelial, but not stromal cells. RT‐PCR revealed that mRNA of HGF is expressed only in stromal cells, and that c‐met mRNA is expressed in both stromal and epithelial cells. These results suggest that HGF plays roles in the proliferation and the regulation of secretory function of bovine endometrial epithelial cells in a paracrine fashion. Mol. Reprod. Dev. 60: 472–480, 2001. © 2001 Wiley‐Liss, Inc.
Cyclic ADPR and calcium signaling in sea bream (Sparus aurata) egg fertilization
Authors: Polzonetti Valeria , Cardinali Marco , Mosconi Gilberto , Natalini Paolo , Meiri Iris , Carnevali Oliana 
Published: August 2002

AbstractThe cell egg is in a state of quiescence and only after its fusion with the sperm, a series of pre‐programmed metabolic processes will be activated, culminating with embryonic development. The egg/sperm fusion induces a transitory increase of Ca2+ in the cytoplasm, which is responsible for the activation of both precocious and late reactions. The release of Ca2+ occurs by stimulation of the ionic specific channels. In addition to IP3, a new Ca‐release inducer was recently evidenced, cyclic ADP ribose (cADPR), in some invertebrates and mammals.Here, we report the first evidence of the cADPR presence in fish. Our data also demonstrate that in the sea bream egg, cADPR is involved in the fertilization process; in fact, its level increases after the entrance of the sperm. By in vitro experiments, it was shown that cADPR induces a release of Ca2+ in the egg homogenate, indicating that in sea bream, the increase of cADPR can induce an intracellular Ca2+ release. Since cADPR is a product of NAD+ metabolism, the activity of several enzymes involved in the NAD+ metabolism was investigated. Sea bream eggs are pelagic and only floating eggs after insemination develop into viable embryos. In the present work, NAD+ metabolism was studied in both types of egg. All the tested enzymes showed similar specific activity in both floating and sinking eggs. In the latter, cADPR was not detectable and the nucleotides content was significantly lower, evidencing a scarce energetic charge in sinking eggs. Mol. Reprod. Dev. 61: 213–217, 2002. © 2002 Wiley‐Liss, Inc.
Neonatal encephalopathy in the term infant: Neuroimaging and inflammatory cytokines
Authors: Foster‐Barber Audrey , Ferriero Donna M. 
Published: August 2002

AbstractThe interrelationship between inflammation and ischemia is complex and poorly understood in the developing nervous system. In the preterm newborn, maternal infection may predispose to white matter injury and may be associated with cytokine elevation. In the term infant, few studies exist linking elevation of cytokines with encephalopathy and poor neurodevelopmental outcome. This review discusses the interplay among inflammatory cytokines, neonatal encephalopathy, and neuroimaging parameters. MRDD Research Reviews 2002;8:20–24. © 2002 Wiley‐Liss, Inc.
Motion artifact reduction and vessel enhancement for free‐breathing navigator‐gated coronary MRA using 3D k‐space reordering
Authors: Huber Michael E. , Hengesbach David , Botnar René M. , Kissinger Kraig V. , Boesiger Peter , Manning Warren J. , Stuber Matthias 
Published: August 2002

AbstractBreathing‐induced bulk motion of the myocardium during data acquisition may cause severe image artifacts in coronary magnetic resonance angiography (MRA). Current motion compensation strategies include breath‐holding or free‐breathing MR navigator gating and tracking techniques. Navigator‐based techniques have been further refined by the applications of sophisticated 2D k‐space reordering techniques. A further improvement in image quality and a reduction of relative scanning duration may be expected from a 3D k‐space reordering scheme. Therefore, a 3D k‐space reordered acquisition scheme including a 3D navigator gated and corrected segmented k‐space gradient echo imaging sequence for coronary MRA was implemented. This new zonal motion‐adapted acquisition and reordering technique (ZMART) was developed on the basis of a numerical simulation of the Bloch equations. The technique was implemented on a commercial 1.5T MR system, and first phantom and in vivo experiments were performed. Consistent with the results of the theoretical findings, the results obtained in the phantom studies demonstrate a significant reduction of motion artifacts when compared to conventional (non‐k‐space reordered) gating techniques. Preliminary in vivo findings also compare favorably with the phantom experiments and theoretical considerations. Magn Reson Med 45:645–652, 2001. © 2001 Wiley‐Liss, Inc.