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PubMed1991

Sex pheromone perception in male pine sawflies, Neodiprion sertifer (Hymenoptera; Diprionidae).

Electroantennographic and single sensillum recordings were performed on male pine sawfly, Neodiprion sertifer, antennae. Responses to the sex pheromone component (2S, 3S, 7S)- 3,7-dimethyl-2-pentadecenyl (diprionyl) acetate (SSS:OAc), to the behavioral inhibitor (2S, 3R, 7R)-diprionyl acetate (SRR:OAc), to the six other enantiomers of diprionyl acetate, and to the biosynthetic precursor diprionol were recorded. Responses to trans-perillenal, a monoterpene identified in female gland extracts and to (2S, 3S, 7S)-diprionyl propionate (SSS:OPr), a field attractant for N. sertifer and some related sawfly species were also recorded. EAG recordings demonstrated a high antennal sensitivity to SSS:OAc and to SSS:OPr. A somewhat lower response was elicited by SRR:OAc. Single sensillum recordings revealed 8-12 different cells firing in each sensillum, corresponding to the number of cells observed in earlier morphological investigations. Out of these cells all, except one, responded to SSS:OAc and to SSS:OPr. No differences in the response to the two components could be observed. The largest amplitude cell in each sensillum was specifically tuned to the behavioral antagonist, SRR:OAc. The pheromone perception system encountered in male pine sawflies thus differs clearly from that observed in moths.

Adaptation, Physiological↗

PubMed2002

Cloning and characterization of a jasmonic acid-responsive gene encoding 12-oxophytodienoic acid reductase in suspension-cultured rice cells.

In suspension-cultured rice ( Oryza sativaL.) cells, jasmonic acid (JA) functions as a signal transducer in elicitor N-acetylchitoheptaose-induced phytoalexin production. Differential screening of a cDNA library constructed using poly(A)(+) RNA from suspension-cultured rice cells treated with JA (10(-4) M) for 2 h yielded a cDNA for a gene that responded to exogenous JA by an increase in mRNA level. Nucleotide sequence analysis indicated that the cDNA encodes an homologue of the yeast Old Yellow Enzyme. The deduced amino acid sequence was very similar to the sequences of 12-oxophytodienoic acid reductases (OPR) 1 and 2 from Arabidopsis thaliana(AtOPR1 and AtOPR2) and OPR1 from tomato ( Lycopersicon esculentum) (LeOPR1). The cDNA-encoded protein purified from recombinant Escherichia coli cells as a hexahistidine-tagged fusion protein exhibited OPR activity similar to that of AtOPR1, AtOPR2, and LeOPR1, which catalyze reduction of (-)- cis-12-oxophytodienoic acid (OPDA) preferentially over (+)- cis-OPDA, a natural precursor of JA. Thus the rice enzyme was termed OsOPR1. The physiological roles of OsOPR1 are discussed. This is the first report of the cloning of an OPR gene from a monocot plant.

Cells, Cultured↗

PubMed2004

Use of surgical sperm retrieval in azoospermic men: a meta-analysis.

OBJECTIVE: To compare the outcome of intracytoplasmic sperm injection (ICSI) cycles [1] using epididymal and testicular sperm in patients with obstructive azoospermia (OA); [2] using surgically retrieved sperm in patients with OA and nonobstructive azoospermia (NOA); and [3] using fresh and frozen-thawed sperm. DESIGN: Meta-analysis of published data. SETTING: Assisted conception unit. PATIENT(S): Ten reports (734 cycles: 677 transfers) were identified as suitable to assess source of sperm; 9 reports (1,103 cycles: 998 transfers) to assess etiology; and 17 reports (1,476 cycles: 1,377 transfers) to assess the effect of cryopreservation. INTERVENTION(S): Surgical sperm retrieval/ICSI. MAIN OUTCOME MEASURE(S): Fertilization rate (FR), implantation rate (IR), clinical pregnancy rate (CPR), and ongoing pregnancy rate (OPR) per embryo transfer. RESULT(S): Meta-analysis demonstrated no significant difference in any outcome measure between the use of epididymal or testicular sperm in men with OA. Meta-analysis showed a significantly improved FR (relative risk [RR] 1.18; 95% confidence interval [CI]: 1.13-1.23) and CPR (RR 1.36; 95% CI: 1.10-1.69) in men with OA as compared to NOA with a nonsignificant increase in OPR. There was no difference in either IR or miscarriage rate between the two groups. Comparing fresh with frozen-thawed epididymal sperm there was no difference in FR or IR, a significantly higher CPR (RR 1.20; 95% CI: 1.0-1.42), and no difference in OPR. No difference in fertilization or pregnancy outcome was noted when the testicular cycles were analyzed separately, but IR was significantly impaired using frozen-thawed sperm (RR 1.75; 95% CI: 1.10-2.80). CONCLUSION(S): Meta-analysis of published data confirms that etiology of azoospermia and cryopreservation of surgically retrieved sperm impacts on ICSI outcome, and allows us to make several recommendations for clinical practice. Origin of sperm, in men with similar etiology, does not affect outcome.

Embryo Transfer↗

PubMed2005

Feasibility, reliability and validity of an operative performance rating system for evaluating surgery residents.

BACKGROUND: Resident evaluation traditionally involves global assessments including clinical performance, professional behavior, technical skill, and number of procedures performed. These evaluations lack objective assessment of operative skills. We describe an operative performance rating system (OPRS) designed to provide objective operative performance ratings using a sentinel procedure format. METHODS: Ten-item procedure-specific rating instruments were developed. Items included technical skills, operative decision making, and general items. A 1 to 5 (5 = excellent) scale was used for evaluation. Six procedures had sufficient forms returned to allow evaluation. Inter-rater reliability was determined by having faculty evaluators view 2 videotaped operations. RESULTS: Return rates for the Internet-based form were full-time faculty (92%), volunteer faculty (27%), and overall (67%). Reliability, (average interitem correlation), and total procedures evaluated were excisional biopsy, 0.90, (0.48), 77; open inguinal herniorraphy, 0.94, (0.62), 51; laparoscopic cholecystectomy, 0.95, (0.64), 75; small-bowel and colon resection, 0.92, (0.58), 30; parathyroidectomy, 0.70, (0.19), 30; and lumpectomy, 0.92, (0.51), 38. Years of training accounted for 25% to 57% of the variation in scores. Inter-rater variability was observed; however, the average rater agreement was reliable. CONCLUSIONS: Internet-based management made obtaining the data feasible. The OPRS complements traditional evaluations by providing objective assessment of operative decision-making and technical skills. Interitem correlations indicate the average rating of items provides a reliable indicator of resident performance. The OPRS is useful in tracking resident development throughout postgraduate training and offers a structured means of certifying operative skills.

Biopsy↗

PubMed2000

Basal follicle-stimulating hormone levels are of limited value in predicting ongoing pregnancy rates after in vitro fertilization.

OBJECTIVE: To evaluate whether basal FSH (bFSH; measured on menstrual day 1-4) adds relevant clinical information to the prediction of ongoing pregnancy rates (OPRs) after IVF, once age and diagnostic characteristics have been taken into account. DESIGN: Retrospective. SETTING: Academic fertility center. PATIENT(S): 435 women undergoing their first IVF cycle. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Ongoing pregnancy rate. RESULT(S): The likelihood ratio of bFSH as a single prognosticator for treatment failure at a cutoff level of 15 IU/L was 3.87. The proportion of patients with such a bFSH level was 5%. Multivariate logistic regression analysis selected age, bFSH level, and infertility diagnosis as relevant predictors of ongoing pregnancy. When compared to a predictive model for OPRs based on age and infertility diagnosis, the inclusion of bFSH into this model helped to identify more patients (22 vs. 1) whose predicted OPR decreased from a low level (5%-12%) towards an extremely low level (<5%). CONCLUSION(S): An acceptable performance of bFSH as a single test to predict treatment failure is only obtained above a high cutoff level. Thus, the number of patients for whom bFSH provides relevant information is small. The predictive model including bFSH identified significantly more patients with an extremely poor prognosis than did the predictive model without bFSH. However, predictions based solely on age and infertility diagnosis usually were already poor in these patients. Measurement of bFSH adds little in only a few patients and is, therefore, debatable.

Adult↗

PubMedDate not supplied

The effect of a pulmonary rehabilitation program on self-efficacy, perception of dyspnea, and physical endurance.

OBJECTIVE: To determine the effect of attendance at an outpatient pulmonary rehabilitation (OPR) program on changes in self-efficacy, perception of dyspnea, and exercise endurance in patients with chronic obstructive pulmonary disease (COPD). DESIGN: Single-group, pretest and posttest design. SETTING: A moderate sized, urban private hospital in western New York. PATIENTS: Sixty patients with a diagnosis of COPD. Their ages ranged from 35 to 82 years (mean +/- SD = 65 +/- 0.75 years). OUTCOME MEASURES: Scores on the COPD Self-Efficacy Scale (CSES) and the Dyspnea Scale and distance walked (feet) on the 12-minute walking-distance test (12 MD). INTERVENTION: The OPR consisted of an educational component and exercise training. Methods to increase self-efficacy were integrated into the rehabilitation program. Preprogram and postprogram measurements were obtained on the CSES, the Dyspnea Scale, and the 12 MD. RESULTS: Paired t tests were used to examine the differences in mean scores between preprogram and postprogram results on the CSES, the Dyspnea Scale, and the 12 MD. There was a significant difference between preprogram and postprogram scores on the CSES (p < 0.01), the Dyspnea Scale (p = 0.01), and the 12 MD (p = 0.04). Pearson product moment correlations showed a significant negative correlation between scores on the CSES and scores on the Dyspnea Scale (r = -0.5566, p = 0.01) and a positive correlation between scores on the CSES and the 12 MD (r = 0.4293, p = 0.05). These results indicated that higher self-efficacy scores on the CSES were correlated with lowered perception of dyspnea and greater distances walked in 12 minutes. CONCLUSIONS: An OPR can improve self-efficacy or confidence in participants' ability to manage or avoid breathing difficulty. Improvement in self-efficacy also may be a factor in decreased perception of dyspnea and increased exercise endurance. Methods to increase self-efficacy expectations with education and exercise training provide an approach to assist persons with COPD to manage their breathing difficulty more effectively. Further studies using a randomized experimental, control design are needed to provide more conclusive direction with regard to effective methods in pulmonary rehabilitation.

Adult↗

PubMed2003

Symmetry and geometry considerations of atom transfer: deoxygenation of (silox)3WNO and R3PO (R = Me, Ph, (t)Bu) by (silox)3M (M = V, NbL (L = PMe3, 4-picoline), Ta; silox = (t)Bu3SiO).

Deoxygenations of (silox)(3)WNO (12) and R(3)PO (R = Me, Ph, (t)Bu) by M(silox)(3) (1-M; M = V, NbL (L = PMe(3), 4-picoline), Ta; silox = (t)Bu(3)SiO) reflect the consequences of electronic effects enforced by a limiting steric environment. 1-Ta rapidly deoxygenated R(3)PO (23 degrees C; R = Me (DeltaG degrees (rxn)(calcd) = -47 kcal/mol), Ph) but not (t)Bu(3)PO (85 degrees, >2 days), and cyclometalation competed with deoxygenation of 12 to (silox)(3)WN (11) and (silox)(3)TaO (3-Ta; DeltaG degrees (rxn)(calcd) = -100 kcal/mol). 1-V deoxygenated 12 slowly and formed stable adducts (silox)(3)V-OPR(3) (3-OPR(3)) with OPR(3). 1-Nb(4-picoline) (S = 0) and 1-NbPMe(3) (S = 1) deoxygenated R(3)PO (23 degrees C; R = Me (DeltaG degrees (rxn)(calcd from 1-Nb) = -47 kcal/mol), Ph) rapidly and 12 slowly (DeltaG degrees (rxn)(calcd) = -100 kcal/mol), and failed to deoxygenate (t)Bu(3)PO. Access to a triplet state is critical for substrate (EO) binding, and the S --> T barrier of approximately 17 kcal/mol (calcd) hinders deoxygenations by 1-Ta, while 1-V (S = 1) and 1-Nb (S --> T barrier approximately 2 kcal/mol) are competent. Once binding occurs, significant mixing with an (1)A(1) excited state derived from population of a sigma-orbital is needed to ensure a low-energy intersystem crossing of the (3)A(2) (reactant) and (1)A(1) (product) states. Correlation of a reactant sigma-orbital with a product sigma-orbital is required, and the greater the degree of bending in the (silox)(3)M-O-E angle, the more mixing energetically lowers the intersystem crossing point. The inability of substrates EO = 12 and (t)Bu(3)PO to attain a bent 90 degree angle M-O-E due to sterics explains their slow or negligible deoxygenations. Syntheses of relevant compounds and ramifications of the results are discussed. X-ray structural details are provided for 3-OPMe(3) (90 degree angle V-O-P = 157.61(9) degrees), 3-OP(t)Bu(3) ( 90 degree angle V-O-P = 180 degrees ), 1-NbPMe(3), and (silox)(3)ClWO (9).

Journal Article↗

PubMed1998

Rhenium(V)-Salen Complexes: Configurational Control and Ligand Exchange.

Reactions of ReO(PPh(3))(2)Cl(3) with tetradentate bis(salicylideneamine) ligands, H(2)salpd (1) and H(2)salbd (2), in different alcohols gave the novel mixed-ligand rhenium complexes ReO(sal)OAlk (OAlk = variety of alkoxy ligands). Configurational studies show that the rhenium complexes ReO(salpd)OAlk (1a-f) display either a symmetrical or a nonsymmetrical configuration, depending on the size of the alcohol and its boiling point. The rhenium complexes ReO(salbd)OAlk (2a-d) are all nonsymmetrical due to the number of carbons that bridge the imine nitrogens. In the case of the symmetrical ReO(salpd)OMe (1a) complex the methoxy ligand can be exchanged for a number of ligands of different types (OAlk, OPh, SAlk, OC(O)Alk). In the newly formed complexes the original configuration was retained except for the ReO(salpd)SAlk (1i,j) complexes which were isolated in the nonsymmetrical configuration. Starting from the nonsymmetrical ReO(salpd)OPr (2c) complex, ligand exchange led to a mixture of the symmetrical and nonsymmetrical complexes, with ratios depending on the reaction time. The crystal structures of ReO(salbd)OPr (2c), and ReO(salpd)OPhOMe (1g) have been determined. ReO(salbd)OPr crystallizes in the triclinic space group P&onemacr;, Z = 2, with a = 10.0344(16) Å, b = 10.647(2) Å, c = 11.481(2) Å, alpha = 86.551(15) degrees, beta = 86.998(14) degrees, gamma = 80.112(15) degrees, V = 1205.1(4) Å(3), and final R = 0.0460. Crystals of ReO(salpd)OPhOMe are orthorhombic, space group P2(1)2(1)2(1), Z = 4, with a = 10.6222(15) Å, b = 12.442(3) Å, c = 16.354(3) Å, V = 2161.4(7) Å(3), and final R = 0.0371. Under the influence of traces of water a number of symmetrical complexes react to a "dimeric" structure, consisting of two ReO(salpd) moieties bridged by an oxygen atom with the bridging Re-O-Re angle symmetrically imposed at 180 degrees. [ReO(salpd)](2)O (3) crystallizes in the monoclinic, space group P2(1)/c, Z = 4, with a = 14.860(2) Å, b = 12.545(2) Å, c = 16.5111(17) Å, beta = 95.030(10) degrees, V = 3066.1(7) Å(3), and final R = 0.0439.

Journal Article↗

PubMed1999

Metal Complexes of New, Chiral N(2)O(2) Tetradentate Ligands.

N,N'-Bis(2R-hydroxy-2R-phenylethyl)-N,N'-dimethyl-1R,2R-diaminocyclohexane, H(2)L1, and N,N'-bis(2S-hydroxy-2S-methylethyl)-N,N'-dimethyl-1R,2R-diaminocyclohexane, H(2)L2, have been synthesized from readily available chiral precursors. They coordinate as neutral tetradentate ligands to Ni(II) and Cu(II) ions, from which the thiocyanates [M(H(2)L)(NCS)(2)] have been isolated and the structures of the H(2)L1 complexes determined by single-crystal X-ray techniques. In the blue complex [Ni(H(2)L1)(NCS)(2)].H(2)O.2EtOH, 1, and green [Cu(H(2)L1)(NCS)(2)]. 0.5H(2)O, 2, the neutral tetradentate ligands coordinate with the cis-alpha geometry with mutually cis N-bound thiocyanate groups, though the chiral ligands adopt a different stereochemistry in the two complexes. In 2, the absolute configuration about the Cu(II) center is Delta, with the nitrogens possessing the S stereochemistry, whereas for the Ni(II) analogue, coordination gives the Lambda isomer with the R configuration at the stereogenic nitrogens. Addition of H(2)L1 or H(2)L2 to Mn(II) in basic methanol solution results in rapid aerial oxidation. Delta-cis-alpha-[Mn(L1)(OMe)(2)].MeOH, 3, was isolated as black crystals from the reaction mixture after addition of 2 mol of NaOMe. The analogous complex with (L2)(2)(-) proved extremely hygroscopic and was not obtained in pure form. Colorless crystals of Lambda-cis-alpha-[MoO(2)(L1)], 4, were precipitated from a methanolic solution of [MoO(2)(acac)(2)] and H(2)L1. The analogous reaction with H(2)L2 gave Delta-cis-alpha-[MoO(2)(L2)], 5. Structures of 3, 4, and 5 are reported. The reactions of H(2)L1 and H(2)L2 with 1 mol equiv of [Ti(OPr(i))(4)] produced the complexes Delta-cis-alpha-[Ti(L1)(OPr(i))(2)] (white solid) and Lambda-cis-alpha-[Ti(L2)(OPr(i))(2)] (colorless oil), structural assignments for which were made possible by analysis of their (1)H NOE difference spectra. Thus the coordination of these tetradentate ligands is stereospecific, but the absolute configuration of the complexes formed (Delta or Lambda) is dependent on the metal ion involved.

Journal Article↗

PubMed2005

Probing the electronic structure of [2Fe-2S] clusters with three coordinate iron sites by use of photoelectron spectroscopy.

Five series of [2Fe-2S] complexes, [Fe(2)S(2)Cl(2)(-)(x)(CN)(x)](-), [Fe(2)S(2)(SEt)(2)(-)(x)Cl(x)](-), [Fe(2)S(2)(SEt)(2)(-)(x)(CN)(x)](-), [Fe(2)S(2)Cl(2)(-)(x)(OAc)(x)](-) (OAc = acetate), and [Fe(2)S(2)(SEt)(2)(-)(x)(OPr)(x)](-) (OPr = propionate) (x = 0-2), were produced by collision-induced dissociation of the corresponding [4Fe-4S] complexes, and their electronic structures were studied by photoelectron spectroscopy. All the [2Fe-2S] complexes contain a [Fe(2)S(2)](+) core similar to that in reduced [2Fe] ferredoxins but with different coordination geometries. For the first three series, which only involve tricoordinated Fe sites, a linear relationship between the measured binding energies and the substitution number (x) was observed, revealing the independent ligand contributions to the total electron binding energies. The effect of the ligand increases in the order SEt --> Cl --> CN, conforming to their electron-withdrawing ability in the same order. The carboxylate ligands in the [Fe(2)S(2)Cl(2)(-)(x)(OAc)(x)](-) and [Fe(2)S(2)(SEt)(2)(-)(x)(OPr)(x)](-) complexes were observed to act as bidentate ligands, giving rise to tetracoordinated iron sites. This is different from their monodentate coordination behavior in the [4Fe-4S] cubane complexes, reflecting the high reactivity of the unsatisfied three-coordinate iron site in the [2Fe-2S] complexes. The [2Fe-2S] complexes with tetracoordinated iron sites exhibit lower electron binding energies, that is, higher reductive activity than the all tricoordinate planar clusters. The electronic structures of all the [2Fe-2S] complexes were shown to conform to the "inverted energy level scheme".

Electrons↗

PubMed2005

Titanium, zinc and alkaline-earth metal complexes supported by bulky O,N,N,O-multidentate ligands: syntheses, characterisation and activity in cyclic ester polymerisation.

The reactions of the bulky amino-bis(phenol) ligand Me(2)NCH(2)CH(2)N[CH(2)-3,5-Bu(t)(2)-C(6)H(2)OH-2](2)(1-H(2)) with Zn[N(SiMe(3))(2)](2)(4), [Mg[N(SiMe(3))(2)](2)](2)(5) and Ca[N(SiMe(3))(2)](2)(THF)(2)(6) yield the complexes 1-Zn, 1-Mg and 1-Ca in good yields. The X-ray structure of 1-Ca showed the complex to be dimeric, with calcium in a distorted octahedral coordination geometry. Five of the positions are occupied by an N(2)O(3) donor set, while the sixth is taken up by an intramolecular close contact to an o-Bu(t) substituent, a rare case of a Ca...H-C agostic interaction (Ca...H distances of 2.37 and 2.41 Angstroms). Another sterically hindered calcium complex, Ca[2-Bu(t)-6-(C(6)F(5)N=CH)C(6)H(3)O](2)(THF)(2).(C(7)H(8))(2/3)(7), was prepared by reaction of 6 with the iminophenol 2-Bu(t)-6-(C(6)F(5)N=CH)C(6)H(3)OH (3-H). According to the crystal structure 7 is monomeric and octahedral, with trans THF ligands. The complex Ti[N[CH(2)-3-Bu(t)-5-Me-C(6)H(2)O-2](2)[CH(2)CH(2)NMe(2)]](OPr(i))(2)(2-Ti) was prepared by treatment of Ti(OPr(i)(4)) with the new amino-bis(phenol) Me(2)NCH(2)CH(2)N[CH(2)-3-Bu(t)-5-Me-C(6)H(2)OH-2](2)(2-H(2)). The reduction of 2-Ti with sodium amalgam gave the titanium(III) salt Ti[N[CH(2)-3-Bu(t)-5-Me-C(6)H(2)O-2](2)[CH(2)CH(2)NMe(2)]](OPr(i))(2).Na(THF)(2)(8). A comparison of the X-ray structures of 2-Ti and 8 showed that the additional electron in 8 significantly reduced the intensity of the pi-bonding from the oxygen atoms of the isopropoxide groups to titanium. 1-Ca and 8 were active initiators for the ring-opening polymerisation of epsilon-caprolactone (up to 97% conversion of 200 equivalents in 2 hours) and yielded polymers with narrow molecular weight distributions.

Biocompatible Materials↗

PubMed2002

Characterization and cDNA-microarray expression analysis of 12-oxophytodienoate reductases reveals differential roles for octadecanoid biosynthesis in the local versus the systemic wound response.

12-Oxophytodienoate reductases (OPRs) belong to a family of flavin-dependent oxidoreductases. With two new tomato isoforms reported here, three OPRs have now been characterized in both tomato and Arabidopsis. Only one of these isoforms (OPR3) participates directly in the octadecanoid pathway for jasmonic acid biosynthesis, as only OPR3 reduces the 9S,13S-stereoisomer of 12-oxophytodienoic acid, the biological precursor of jasmonic acid. The subcellular localization of OPRs was analyzed in tomato and Arabidopsis. The OPR3 protein and activity were consistently found in peroxisomes where they co-localize with the enzymes of beta-oxidation which catalyze the final steps in the formation of jasmonic acid. The octadecanoid pathway is thus confined to plastids and peroxisomes and, in contrast to previous assumptions, does not involve the cytosolic compartment. The expression of tomato (Lycopersicon esculentum,Le) OPR3 was analyzed in the context of defense-related genes using a microarray comprising 233 cDNA probes. LeOPR3 was found to be up-regulated after wounding with induction kinetics resembling those of other octadecanoid pathway enzymes. In contrast to the induction of genes for wound response proteins (e.g. proteinase inhibitors), the accumulation of octadecanoid pathway transcripts was found to be more rapid and transient in wounded leaves, but hardly detectable in unwounded, systemic leaves. Consistent with the expression data, OPDA and JA were found to accumulate locally but not systemically in the leaves of wounded tomato plants. The transcriptional activation of the octadecanoid pathway and the accumulation of JA to high levels are, thus not required for the activation of defense gene expression in systemic tissues.

Arabidopsis↗

PubMed1999

Prevention of twin pregnancy after in-vitro fertilization or intracytoplasmic sperm injection based on strict embryo criteria: a prospective randomized clinical trial.

A prospective randomized study comparing single embryo transfer with double embryo transfer after in-vitro fertilization or intracytoplasmic sperm injection (IVF/ICSI) was carried out. First, top quality embryo characteristics were delineated by retrospectively analysing embryos resulting in ongoing twins after double embryo transfer. A top quality embryo was characterized by the presence of 4 or 5 blastomeres at day 2 and at least 7 blastomeres on day 3 after insemination, the absence of multinucleated blastomeres and <20% cellular fragments on day 2 and day 3 after fertilization. Using these criteria, a prospective study was conducted in women <34 years of age, who started their first IVF/ICSI cycle. Of 194 eligible patients, 110 agreed to participate of whom 53 produced at least two top quality embryos and were prospectively randomized. In all, 26 single embryo transfers resulted in 17 conceptions, 14 clinical and 10 ongoing pregnancies [implantation rate (IR) = 42.3%; ongoing pregnancy rate (OPR) = 38.5%] with one monozygotic twin; 27 double embryo transfers resulted in 20 ongoing conceptions with six (30%) twins (IR = 48.1%; OPR = 74%). We conclude that by using single embryo transfer and strict embryo criteria, an OPR similar to that in normal fertile couples can be achieved after IVF/ICSI, while limiting the dizygotic twin pregnancy rate to its natural incidence of <1% of all ongoing pregnancies.

Adult↗

PubMed2001

The spin temperature of NH3 in Comet C/1999S4 (LINEAR).

A high-dispersion spectrum of Comet C/1999S4 (LINEAR) was obtained in the optical region with the high-dispersion spectrograph on the Subaru telescope when the comet was 0.863 astronomical units from the Sun before its disintegration. We obtained high signal-to-noise ratio emission lines of the cometary NH2 bands from which an ortho-to-para ratio (OPR) of 3.33 +/- 0.07 was derived on the basis of a fluorescence excitation model. Assuming that cometary NH2 mainly originates from ammonia through photodissociation, the derived OPR of NH2 molecules should reflect that of ammonia, which provides information on the environment of molecular formation or condensation and of the thermal history of cometary ices. Assuming that the OPR of ammonia in comets was unchanged in the nucleus, the derived spin temperature of ammonia (28 +/- 2 kelvin) suggests that a formation region of the cometary ammonia ice was between the orbit of Saturn and that of Uranus in the solar nebula.

Ammonia↗

PubMed1997

Evidence that endogenous relaxin promotes growth of the vagina and uterus during pregnancy in gilts.

Recently, it was demonstrated that endogenous relaxin promotes growth of the vagina during the second half of pregnancy in rats and that administration of porcine relaxin promotes growth of the uterus in nonpregnant or early pregnant gilts. This study examined the effects of circulating relaxin on growth of both the vagina and uterus during the last two thirds of the 114-day gestation period in gilts. Furthermore, this study employed an in vitro immunohistochemical localization technique to determine whether the vagina and uterus in pigs have specific relaxin-binding sites. Three groups of pregnant gilts were used: sham-ovariectomized controls (group C; n = 8), ovariectomized progesterone-treated (group OP; n = 6), and ovariectomized progesterone- plus relaxin-treated (group OPR; n = 7). Gilts were either sham ovariectomized or ovariectomized on day 40 of gestation. Hormone replacement therapy with progesterone (group OP), progesterone plus relaxin (group OPR), or hormone vehicles (group C) began on day 38 (progesterone) or day 40 (relaxin) and continued until day 110. On day 110, the vagina and uterus were collected, and wet weight, dry weight, and percent hydration were determined. Small pieces (2-3 cm3) of the vagina and uterus from groups C and OP were frozen and cryosectioned for the immunohistochemical localization of relaxin-binding sites. Relaxin promoted growth of both the vagina and uterus. The wet weights of both the vagina and uterus in relaxin-deficient gilts (group OP) were lower (P < 0.05) than those in controls (group C), and relaxin replacement therapy (group OPR) restored the wet weights of both tissues to values that did not differ from those in controls. The mean dry weights and percent hydrations in the vagina and uterus did not differ among treatments. Immunohistochemical localization studies in the vagina and uterus demonstrated that specific and saturable binding of relaxin was localized in the same cell types of both tissues, namely epithelial cells (luminal in vagina, and both luminal and glandular in uterus), smooth muscle cells (both circular and longitudinal in vagina, and myometrial in uterus), and cells associated with blood vessels. In conclusion, this study provides evidence that circulating relaxin promotes growth of both the vagina and uterus during pregnancy in the pig. Furthermore, this study provides evidence that both the vagina and uterus contain specific and saturable relaxin-binding sites in epithelial cells, smooth muscle cells, and cells associated with blood vessels. We conclude that these cells probably initiate relaxin's effects on the vagina and uterus of the pregnant pig.

Animals↗

PubMed1998

Bremazocine recognizes the difference in four amino acid residues to discriminate between a nociceptin/orphanin FQ receptor and opioid receptors.

We investigated the molecular basis of the discrimination between nociceptin/orphanin FQ receptor (NociR) and opioid receptors (OPRs) by bremazocine, a non-type-selective opioid ligand. Construction of several chimeric receptors between NociR and kappa-opioid receptor (KOPR) and mutant NociRs followed by binding experiments with [3H]bremazocine showed that the mutation of only four amino acid residues of NociR, Ala216, Val279, Gln280 and Val281, to the amino acid residues located at the corresponding position of KOPR, Lys227, Ile290, His291 and Ile292, made it possible for the resultant mutant NociR to bind bremazocine with high affinity. Considering that these four amino acid residues are conserved among mu-, delta- and kappa-OPRs, the present result suggests that bremazocine recognizes the difference in these four amino acid residues to discriminate between NociR and OPRs.

Amino Acid Sequence↗

PubMed1975

Psychological characteristics of deep submergence vehicle personnel.

The personality and developmental characteristics of U.S. Navy Deep Submergence Vehicle (DSV) personnel, including operators and crews, were documented and compared to the characteristics of U.S. Navy divers. The results show that DSV operators (DSV Oprs) had a significantly less asocial developmental pattern than divers, while developmental experiences of DSV crews (DSV Crs) were similar to those of divers. Personality measures (EPPS) indicate that both DSV Oprs and DSV Crs are presently more sociable as adults than divers and would probably be more effective in situations involving small group interaction. The modifications which have occurred in the behavior of DSV Crs may be related to experience in the highly interpersonal DSV situation. The findings also show that DSV Oprs prefer to take fewer risks than divers, while the DSV Crs are more like divers in risk-taking behavior. The implications of this research to DSV mission effectiveness are discussed.

Adult↗

PubMed1990

Specific inactivation of prolyl 4-hydroxylase and inhibition of collagen synthesis by oxaproline-containing peptides in cultured human skin fibroblasts.

The crucial role of collagen in fibrotic disorders has prompted attempts to develop drugs that inhibit collagen accumulation. Peptides containing the unphysiological amino acid 5-oxaproline (Opr) have recently been found to act as specific syncatalytic inactivators of pure prolyl 4-hydroxylase, the enzyme that catalyzes the formation of 4-hydroxyproline in collagens. The present study indicates that oxaproline-containing peptides benzyloxycarbonyl-Phe-Opr-Gly-benzyl ester (I) and benzyloxycarbonyl-Phe-Opr-Gly-ethyl ester (II) inactivate prolyl 4-hydroxylase in cultured human skin fibroblasts, peptide I being about twice as potent as peptide II. Inactivation by 50% was observed after culturing with about 20-40 microM concentrations of peptide I for 48 h. The inactivation appears to be specific, as no changes were found in the activities of two other intracellular enzymes of collagen synthesis, lysyl hydroxylase and galactosylhydroxylysyl glucosyltransferase. Synthesis of 4-hydroxyproline by the cells was markedly decreased, and 4-hydroxyproline-deficient procollagen accumulated intracellularly, whereas no changes were found in the incorporation of [14C]leucine into protein after culturing of the cells with a 30 microM concentration of peptide I for 48 h. No changes were seen in the viability of the cells or the release of lactate dehydrogenase from them into the culture medium. No significant changes were found in the steady-state levels of the mRNAs for the pro-alpha 1 chains of type I and type III procollagens or for the alpha and beta subunits of prolyl 4-hyroxylase or fibronectin after culturing with 75 microM peptide I for 48 h. The data indicate that inactivation of cellular prolyl 4-hydroxylase has marked effects on cellular 4-hydroxyproline formation and collagen secretion but no effects on the steady-state levels of mRNAs for type I and III procollagens or the two types of subunit of prolyl 4-hydroxylase.

Cells, Cultured↗