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1.
Acta Crystallogr C Struct Chem ; 72(Pt 5): 416-20, 2016 05 01.
Article in English | MEDLINE | ID: mdl-27146571

ABSTRACT

Vanadium chemistry is of interest due its biological relevance and medical applications. In particular, the interactions of high-valent vanadium ions with sulfur-containing biologically important molecules, such as cysteine and glutathione, might be related to the redox conversion of vanadium in ascidians, the function of amavadin (a vanadium-containing anion) and the antidiabetic behaviour of vanadium compounds. A mechanistic understanding of these aspects is important. In an effort to investigate high-valent vanadium-sulfur chemistry, we have synthesized and characterized the non-oxo divanadium(IV) complex salt tetraphenylphosphonium tri-µ-methanolato-κ(6)O:O-bis({tris[2-sulfanidyl-3-(trimethylsilyl)phenyl]phosphane-κ(4)P,S,S',S''}vanadium(IV)) methanol disolvate, (C24H20P)[V(IV)2(µ-OCH3)3(C27H36PS3)2]·2CH3OH. Two V(IV) metal centres are bridged by three methanolate ligands, giving a C2-symmetric V2(µ-OMe)3 core structure. Each V(IV) centre adopts a monocapped trigonal antiprismatic geometry, with the P atom situated in the capping position and the three S atoms and three O atoms forming two triangular faces of the trigonal antiprism. The magnetic data indicate a paramagnetic nature of the salt, with an S = 1 spin state.


Subject(s)
Coordination Complexes/chemistry , Phosphines/chemistry , Vanadium/chemistry , Crystallography, X-Ray , Ligands , Magnets/chemistry , Models, Molecular , Sulfur/chemistry
2.
Dalton Trans ; 44(10): 4468-73, 2015 Mar 14.
Article in English | MEDLINE | ID: mdl-25645817

ABSTRACT

In our effort to study vanadium chalcogenide chemistry, we have synthesized and characterized a class of non-oxido divanadium(IV) and divanadium(V) complexes with chalcogenide and dichalcogenide as bridges. All structures consist of a similar divanadium motif, in which two metal centers are bridged by one µ-chalcogenide and one µ-η(2):η(2)-dichalcogenide, forming a V2(µ-E)(µ-η(2):η(2)-E2) (E = S or Se) core structure. These compounds are [V(IV)2(PS3)2(µ-Se2)(µ-Se)][PPh4]2 (1), [V(V)2(PS3'')2(µ-Se2)(µ-Se)] (2), [V(V)2(PS3'')2(µ-S2)(µ-S)] (3a) and [V(V)2(PS3)2(µ-S2)(µ-S)] (3b) ([PS3](3-) = P(C6H4-2-S)3 and [PS3''](3-) = P(C6H3-3-SiMe3-2-S)3). Compound 1 exhibits diamagnetic behavior, indicating strong antiferromagnetic coupling between two d(1) centers. Compounds 2 and 3a-b have the highest oxidation states for vanadium ions (+5/+5) among those reported divanadium chalcogenide clusters. The work demonstrates that high-valent divanadium chalcogenide clusters can be obtained with the activation of elemental chalcogens by low-valent vanadium ions.


Subject(s)
Chalcogens/chemistry , Coordination Complexes/chemistry , Sulfhydryl Compounds/chemistry , Vanadium/chemistry , Crystallography, X-Ray , Models, Molecular , Oxidation-Reduction
3.
Taiwan J Obstet Gynecol ; 52(4): 512-5, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24411035

ABSTRACT

OBJECTIVE: This study investigated the occurrence of peritoneal fluid in women undergoing intrauterine insemination (IUI) and its correlation with the stage of pelvic endometriosis and its influence on pregnancy outcomes. MATERIALS AND METHODS: A retrospective case-control design was used to recruit 272 infertile women with pelvic endometriosis. The treatment protocol consisted of controlled ovarian hyperstimulation with downregulation and gonadotropin for IUI treatment following ultrasound and laparoscopic intervention. The amount and color of the peritoneal fluid were determined during laparoscopy. RESULTS: The mean amount of peritoneal fluid with pelvic endometriosis that was detected using transvaginal ultrasound was ~ 15.1 mL. Women whose cycles contained more peritoneal fluid had significantly lower pregnancy rates (17.2% and 31.3%, respectively). The total clinical pregnancy rate was not significantly different between the two groups with reddish and yellowish peritoneal fluid who had pelvic endometriosis. CONCLUSION: Pelvic endometriosis and peritoneal fluid, detected through vaginal ultrasound, have negative effects on the pregnancy outcome of IUI treatment.


Subject(s)
Ascites/etiology , Ascitic Fluid , Endometriosis/complications , Infertility, Female/therapy , Pregnancy Rate , Adult , Ascites/diagnostic imaging , Ascitic Fluid/diagnostic imaging , Case-Control Studies , Color , Endometriosis/diagnostic imaging , Endometriosis/surgery , Female , Humans , Insemination, Artificial , Pelvis , Pregnancy , Retrospective Studies , Ultrasonography
4.
J Obstet Gynaecol Res ; 37(1): 71-4, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21083836

ABSTRACT

Uterine rupture during near-term pregnancy is a life-threatening condition. A 31-year-old pregnant woman with a breech presentation at the gestation age of 35(+2) weeks had complained of a dull abdominal pain for days. She was treated 2 years ago with bilateral uterine artery ligation and hysterotomy for removal of the retained placenta. An aggravation of abdominal pain occurred suddenly 4 h after hospitalization. The cardiotocogram showed a fetal heart beat with loss of variability, but increasing deceleration. An urgent cesarean section was performed because of suspected placenta abruption. After successful delivery of the fetus, a protruding placental tissue was found on the fundal uterine wall. We performed wedge resection of the ruptured uterine wall with the aid of an intrauterine muscle injection of 20 IU oxytocin, a local injection of diluted vasopressin (1:60) into the myometrium around and into the rupture site, an intramuscular injection of 0.2 mg methylergonovine, and primary repair of the defect, but in vain. Cesarean hysterectomy was used to control the intractable bleeding. The accumulated blood loss was more than 10,000 mL. The final pathology confirmed placenta percreta with uterine rupture. Luckily, both mother and fetus recovered well and were discharged 7 days later. We concluded that women with retained placenta and/or postpartum hemorrhage managed by previous hysterotomy and uterine artery ligation still need careful prenatal care, since the possibility of re-occurrence of the placenta percreta is easily overlooked and may result in a further life-threatening situation, such as the uterine rupture in this case.


Subject(s)
Hysterotomy , Placenta Accreta/physiopathology , Uterine Rupture/etiology , Uterine Rupture/surgery , Adult , Female , Humans , Hysterotomy/adverse effects , Pregnancy , Pregnancy Outcome , Pregnancy Trimester, Third
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