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1.
Acta Radiol Open ; 13(5): 20584601241248820, 2024 May.
Article in English | MEDLINE | ID: mdl-38737558

ABSTRACT

Background: Fetal ultrasound has limitations, especially if the patient is obese or in cases with oligohydramnios. Magnetic resonance imaging (MRI) can then be used as a complement, but only few studies have focused on examinations in the second trimester. Purpose: To validate MRI as a complement to diagnose fetal anomalies in the second trimester. Material and Methods: This retrospective study retrieved data from January 2008 to July 2012 from the Fetal Medicine Unit and Department of Radiology at Uppsala University Hospital. Ultrasound and MRI findings were reviewed in 121 fetuses in relation to the final diagnosis, including postpartum follow-up and autopsy results. Results: Of the 121 fetuses, 51 (42%) had a CNS anomaly and 70 (58%) a non-CNS anomaly diagnosed or suspected. MRI provided additional information in 21% of all cases without changing the management and revealed information that changed the management of the pregnancy in 13%. When a CNS anomaly was detected or suspected, the MRI provided additional information in 22% and changed the management in 10%. The corresponding figures for non-CNS cases were 21% and 16%, respectively. The proportion of cases with additional information that changed the management was especially high in patients with a BMI >30 kg/m2 (25%) and in patients with oligohydramnios (38%). In five cases in category III, false-positive ultrasound findings were identified. Conclusions: MRI in the second trimester complements ultrasound and improves diagnosis of fetal CNS- and non-CNS anomalies especially when oligohydramnios or maternal obesity is present.

2.
ACS Cent Sci ; 9(12): 2225-2240, 2023 Dec 27.
Article in English | MEDLINE | ID: mdl-38161378

ABSTRACT

Extended conjugated polyynes provide models for the elusive sp carbon polymer carbyne, but progress has been hampered by numerous synthetic challenges. Stabilities appear to be enhanced by bulky, electropositive transition-metal endgroups. Reactions of trans-(C6F5)(p-tol3P)2Pt(C≡C)nSiEt3 (n = 4-6, PtCxSi (x = 2n)) with n-Bu4N+F-/Me3SiCl followed by excess tetrayne H(C≡C)4SiEt3 (HC8Si) and then CuCl/TMEDA and O2 give the heterocoupling products PtCx+8Si, PtCx+16Si, and sometimes higher homologues. The PtCx+16Si species presumably arise via protodesilylation of PtCx+8Si under the reaction conditions. Chromatography allows the separation of PtC16Si, PtC24Si, and PtC32Si (from n = 4), PtC18Si and PtC26Si (n = 5), or PtC20Si and PtC28Si (n = 6). These and previously reported species are applied in similar oxidative homocouplings, affording the family of diplatinum polyynediyl complexes PtCxPt (x = 20, 24, 28, 32, 36, 40 in 96-34% yields and x = 44, 48, 52 in 22-7% yields). These are carefully characterized by 13C NMR, UV-visible, and Raman spectroscopy and other techniques, with particular attention to behavior as the Cx chain approaches the macromolecular limit and endgroup effects diminish. The crystal structures of solvates of PtC20Pt, PtC24Pt, and PtC26Si, which feature the longest sp chains structurally characterized to date, are analyzed in detail. All data support a polyyne electronic structure with a nonzero optical band gap and bond length alternation for carbyne.

3.
Molecules ; 26(16)2021 Aug 09.
Article in English | MEDLINE | ID: mdl-34443404

ABSTRACT

Novel dyes were prepared by simple "click CuAAC" attachment of a triarylborane-alkyne to the azide side chain of an amino acid yielding triarylborane dye 1 which was conjugated with pyrene (dye 2) forming a triarylborane-pyrene FRET pair. In contrast to previous cationic triarylboranes, the novel neutral dyes interact only with proteins, while their affinity to DNA/RNA is completely abolished. Both the reference triarylborane amino acid and triarylborane-pyrene conjugate bind to BSA and the hDPP III enzyme with high affinities, exhibiting a strong (up to 100-fold) fluorescence increase, whereby the triarylborane-pyrene conjugate additionally retained FRET upon binding to the protein. Furthermore, the triarylborane dyes, upon binding to the hDPP III enzyme, did not impair its enzymatic activity under a wide range of experimental conditions, thus being the first non-covalent fluorimetric markers for hDPP III, also applicable during enzymatic reactions with hDPP III substrates.


Subject(s)
Coloring Agents/chemistry , Cyclohexanes/chemistry , Fluorescent Dyes/chemistry , Fluorometry , Indoles/chemistry , Alkynes/chemistry , Amino Acids/chemistry , Azides/chemistry , Pyrenes/chemistry
4.
Chemistry ; 27(49): 12619-12634, 2021 Sep 01.
Article in English | MEDLINE | ID: mdl-34101914

ABSTRACT

The silylated hexatriynyl complex trans-(C6 F5 )(p-tol3 P)2 Pt(C≡C)3 SiEt3 (PtC6 TES) is converted in situ to PtC6 H (wet n-Bu4 N+ F- , THF) and cross coupled with the diyne H(C≡C)2 SiEt3 (HC4 TES; CuCl/TMEDA, O2 ) to give PtC10 TES (71 %). This sequence is repeated twice to afford PtC14 TES (65 %) and then PtC18 TES (27 %). An analogous series of reactions starting with PtC8 TES gives PtC12 TES (60 %), then PtC16 TES (43 %), and then PtC20 TES (17 %). Similar cross couplings with H(C≡C)2 Si(i-Pr)3 (HC4 TIPS) give PtC12 TIPS (68 %), PtC14 TIPS (68 %), and PtC16 TIPS (34 %). The trialkylsilyl species (up to PtC18 TES) are converted to 3+2 "click" cycloadducts or 1,4-disubstituted 1,2,3-triazoles trans-(C6 F5 )(p-tol3 P)2 Pt(C≡C)n-1 C=CHN(CH2 C6 H5 )N=N (29-92 % after workups). The most general procedure involves generating the terminal polyynes PtCx H (wet n-Bu4 N+ F- , THF) in the presence of benzyl azide in DMF and aqueous CuSO4 /ascorbic acid. All of the preceding complexes are crystallographically characterized and the structural and spectroscopic properties analyzed as a function of chain length. Two pseudopolymorphs of PtC20 TES are obtained, both of which feature molecules with parallel sp carbon chains in a pairwise head/tail packing motif with extensive sp/sp van der Waals contacts.


Subject(s)
Carbon , Copper , Azides , Catalysis , Cycloaddition Reaction
5.
Chemistry ; 26(27): 6017-6028, 2020 May 12.
Article in English | MEDLINE | ID: mdl-32104942

ABSTRACT

A bis-triarylborane tetracation (4-Ar2 B-3,5-Me2 C6 H2 )-C≡C-C≡C-(3,5-Me2 C6 H2 -4-BAr2 [Ar=(2,6-Me2 -4-NMe3 -C6 H2 )+ ] (24+ ) shows distinctly different behaviour in its fluorimetric response than that of our recently published bis-triarylborane 5-(4-Ar2 B-3,5-Me2 C6 H2 )-2,2'-(C4 H2 S)2 -5'-(3,5-Me2 C6 H2 -4-BAr2 ) (34+ ). Single-crystal X-ray diffraction data on the neutral bis-triarylborane precursor 2 N confirm its rod-like dumbbell structure, which is shown to be important for DNA/RNA targeting and also for BSA protein binding. Fluorimetric titrations with DNA/RNA/BSA revealed the very strong affinity of 24+ and indicated the importance of the properties of the linker connecting the two triarylboranes. Using the butadiyne rather than a bithiophene linker resulted in an opposite emission effect (quenching vs. enhancement), and 24+ bound to BSA 100 times stronger than 34+ . Moreover, 24+ interacted strongly with ss-RNA, and circular dichroism (CD) results suggest ss-RNA chain-wrapping around the rod-like bis-triarylborane dumbbell structure like a thread around a spindle, a very unusual mode of binding of ss-RNA with small molecules. Furthermore, 24+ yielded strong Raman/SERS signals, allowing DNA or protein detection at ca. 10 nm concentrations. The above observations, combined with low cytotoxicity, efficient human cell uptake and organelle-selective accumulation make such compounds intriguing novel lead structures for bio-oriented, dual fluorescence/Raman-based applications.


Subject(s)
Butadienes/chemistry , DNA/chemistry , RNA/chemistry , Circular Dichroism , Crystallography, X-Ray , Fluorescence , Fluorometry , Humans , Molecular Structure
6.
Chemistry ; 25(69): 15896-15914, 2019 Dec 10.
Article in English | MEDLINE | ID: mdl-31596000

ABSTRACT

The platinum polyynyl complexes trans-(C6 F5 )(p-tol3 P)2 Pt(C≡C)n/2 H undergo oxidative homocoupling (O2 , CuCl/TMEDA) to diplatinum polyynediyl complexes trans, trans-(C6 F5 )(p-tol3 P)2 Pt(C≡C)n Pt(Pp-tol3 )2 (C6 F5 ) (n=4, 2; 6, 5; 8, 8; 92-97 %) as reported previously. When related reactions are conducted in the presence of CuI adducts of the 1,10-phenanthroline-based macrocycles 2,9-(1,10-phenanthrolinediyl)(p-C6 H4 O(CH2 )6 O)2 (1,3-C6 H4 ) (10, 33-membered) or 2,9-(1,10-phenanthrolinediyl)(p-C6 H4 O(CH2 )6 O)2 (2,7-naphthalenediyl) (11, 35-membered), excess K2 CO3 , and I2 (oxidant), rotaxanes are isolated that feature a Pt(C≡C)n Pt axle that has been threaded through the macrocycle (2⋅10, 9 %; 5⋅10, 41 %; 5⋅11, 28 %; 8⋅10, 12 %; 8⋅11, 9 %). Their crystal structures are determined and analyzed in detail, particularly with respect to geometric perturbations and the degree of steric sp carbon chain insulation. NMR spectra show a number of shielding effects. UV/Vis spectra do not indicate significant electronic interactions between the Pt(C≡C)n Pt axles and macrocycles, although cyclic voltammetry data suggest rapid reactions following oxidation.

7.
Dalton Trans ; 48(17): 5800-5816, 2019 Apr 23.
Article in English | MEDLINE | ID: mdl-30977490

ABSTRACT

Reaction of (p-tol3P)2PtCl2 and Me3Sn(C[triple bond, length as m-dash]C)2SiMe3 (1 : 1/THF/reflux) gives monosubstituted trans-Cl(p-tol3P)2Pt(C[triple bond, length as m-dash]C)2SiMe3 (63%), which with wet n-Bu4N+ F- yields trans-Cl(p-tol3P)2Pt(C[triple bond, length as m-dash]C)2H (2, 96%). Hay oxidative homocoupling (O2/CuCl/TMEDA) gives all-trans-Cl(p-tol3P)2Pt(C[triple bond, length as m-dash]C)4Pt(Pp-tol3)2Cl (3, 68%). Reaction of 3 and Me3Sn(C[triple bond, length as m-dash]C)2SiMe3 (1 : 1/rt) affords monosubstituted all-trans-Cl(p-tol3P)2Pt(C[triple bond, length as m-dash]C)4Pt(Pp-tol3)2(C[triple bond, length as m-dash]C)2SiMe3 (46%), which is converted by a similar desilylation/homocoupling sequence to all-trans-Cl[(p-tol3P)2Pt(C[triple bond, length as m-dash]C)4]3Pt(Pp-tol3)2Cl (7; 79%). Reaction of (p-tol3P)2PtCl2 and excess H(C[triple bond, length as m-dash]C)2SiMe3 (HNEt2/cat. CuI) gives trans-Me3Si(C[triple bond, length as m-dash]C)2Pt(Pp-tol3)2(C[triple bond, length as m-dash]C)2SiMe3 (78%), which with wet n-Bu4N+ F- affords trans-H(C[triple bond, length as m-dash]C)2Pt(Pp-tol3)2(C[triple bond, length as m-dash]C)2H (96%). Hay oxidative cross coupling with 2 (1 : 4) gives all-trans-Cl[(p-tol3P)2Pt(C[triple bond, length as m-dash]C)4]2Pt(Pp-tol3)2Cl (10, 36%) along with homocoupling product 3 (33%). Reaction of 3 and Me3Sn(C[triple bond, length as m-dash]C)2SiMe3 (1 : 2/rt) yields all-trans-Me3Si(C[triple bond, length as m-dash]C)2(p-tol3P)2Pt(C[triple bond, length as m-dash]C)4Pt(Pp-tol3)2(C[triple bond, length as m-dash]C)2SiMe3 (17, 77%), which with wet n-Bu4N+ F- gives all-trans-H(C[triple bond, length as m-dash]C)2(p-tol3P)2Pt(C[triple bond, length as m-dash]C)4Pt(Pp-tol3)2(C[triple bond, length as m-dash]C)2H (96%). Reaction of 3 and excess Me3P gives all-trans-Cl(Me3P)2Pt(C[triple bond, length as m-dash]C)4Pt(PMe3)2Cl (4, 86%). A model reaction of trans-(p-tol)(p-tol3P)2PtCl and KSAc yields trans-(p-tol)(p-tol3P)2PtSAc (12, 75%). Similar reactions of 3, 7, 10, and 4 give all-trans-AcS[(R3P)2Pt(C[triple bond, length as m-dash]C)4]nPt(PR3)2SAc (76-91%). The crystal structures of 3, 17, and 12 are determined. The first exhibits a chlorine-chlorine distance of 17.42 Å; those in 10 and 7 are estimated as 30.3 Å and 43.1 Å.

8.
Inorg Chem ; 56(4): 2145-2152, 2017 Feb 20.
Article in English | MEDLINE | ID: mdl-28165752

ABSTRACT

Unusual cis-oxidative addition of methyltrioxorhenium (MTO) to [PtMe2(bpy)], (bpy = 2,2'-bipyridine) (1) is described. Addition of MTO to 1 first gives the Lewis acid-base adduct [(bpy)Me2Pt-Re(Me)(O)3] (2) and subsequently affords the oxidative addition product [(bpy)Me3PtReO3] (3). All complexes 1, MTO, 2, and 3 are in equilibrium in solution. The structure of 2 was confirmed by X-ray crystallography, and its dissociation constant in solution is 0.87 M. The structure of 3 was confirmed by extended X-ray absorption fine structure and X-ray absorption near-edge structure in tandem with one- and two-dimensional NMR spectroscopy augmented by deuterium and 13C isotope-labeling studies. Kinetics of formation of compound 3 revealed saturation kinetics dependence on [MTO] and first-order in [Pt], complying with prior equilibrium formation of 2 with oxidative addition of Me-Re being the rate-determining step. Exposure of 3 to molecular oxygen or air resulted in the insertion of an oxygen atom into the platinum-rhenium bond forming [(bpy)Me3PtOReO3] (4) as final product. Density functional theory analysis on oxygen insertion pathways leading to complex 4, merited on the basis of Russell oxidation pathway, revealed the involvement of rhenium peroxo species.

9.
Acta Obstet Gynecol Scand ; 90(4): 380-9, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21306331

ABSTRACT

OBJECTIVE: To evaluate the additional information of second trimester magnetic resonance imaging (MRI) compared with ultrasound in fetuses with identified or suspected non-CNS anomalies and to study the clinical impact of the MRI information on pregnancy management. DESIGN: Prospective study during 2003-2007. The fetal MRI examination was planned to be performed within 3 days after the ultrasound. SETTING: Uppsala University hospital. SAMPLE: Sixty-three women in whom the second trimester ultrasound identified or raised suspicion of fetal anomalies were included. METHODS: Ultrasound was compared to MRI in relation to the final diagnosis, which was based on the assessment of all available data, including postpartum clinical follow-up and autopsy results. MAIN OUTCOME MEASURES: Evaluation of the additional information gained from MRI and the consequences it had on pregnancy management. RESULTS: The mean interval between ultrasound and MRI was 2.6 days (range 0-15 days). In 42 (67%) women MRI was performed within 3 days. All MRI examinations were assessable. In 43 (68%) fetuses MRI provided no additional information, in 17 (27%) MRI added information without changing the management and in three (5%) MRI provided additional information which changed the management. All these three cases had oligohydramnios. In all six cases of diaphragmatic hernia MRI provided additional information. CONCLUSIONS: Fetal MRI of non-CNS anomalies in the second trimester seems to be a valuable adjunct to ultrasound diagnosis of non-CNS anomalies, especially in cases of oligohydramnios and diaphragmatic hernia.


Subject(s)
Fetus/abnormalities , Magnetic Resonance Imaging/methods , Prenatal Diagnosis/methods , Ultrasonography, Prenatal/methods , Adult , Female , Humans , Infant, Newborn , Magnetic Resonance Imaging/standards , Pregnancy , Pregnancy Trimester, Second , Prenatal Diagnosis/standards , Prospective Studies , Ultrasonography, Prenatal/standards , Young Adult
10.
Neuroradiology ; 53(1): 43-8, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20878397

ABSTRACT

INTRODUCTION: To obtain measurements of the normal fetal brain before 24 weeks of gestation (GW), a deadline for medical decisions on fetal viability in a large number of countries. METHODS: We retrospectively reviewed 70 normal MR examinations of fetuses aged GW 17 to 23. The fronto-occipital diameter, the cerebral bi-parietal diameter, the transverse cerebellar diameter, the vermian height, and antero-posterior diameter were measured. RESULTS: The median, maximum, and minimum values for each parameter were displayed for each individual GW. CONCLUSION: The recorded data might contribute to a better assessment of fetal health by providing normal boundaries for the brain growth.


Subject(s)
Brain/anatomy & histology , Brain/embryology , Magnetic Resonance Imaging/methods , Models, Anatomic , Pregnancy Trimester, Second , Prenatal Diagnosis/methods , Computer Simulation , Female , Humans , Pregnancy , Reference Values , Reproducibility of Results , Sensitivity and Specificity
11.
Acta Obstet Gynecol Scand ; 89(12): 1571-81, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21080900

ABSTRACT

OBJECTIVES: to evaluate the additional information of second trimester magnetic resonance imaging (MRI) compared to ultrasound in fetuses with identified or suspected central nervous system (CNS) anomalies and to study the clinical impact of the information on pregnancy management. DESIGN: prospective study during 2004-2007. The fetal MRI examination was planned to be performed within 3 days after the ultrasound. Setting. Uppsala University hospital. MATERIAL: twenty-nine pregnant women in whom second trimester ultrasound identified or suspected fetal CNS anomalies. MAIN OUTCOME MEASURES: evaluation of the additional information gained from MRI and the consequence it had on pregnancy management. RESULTS: the mean interval between ultrasound and MRI was 1.6 days (range 0-7). In 16 fetuses (55%), MRI verified the ultrasound diagnosis but provided no additional information, while in 10 (35%) MRI gave additional information without changing the management. In 3 (10%), MRI provided additional information that changed the management of the pregnancy. Two of these women were obese. CONCLUSIONS: fetal MRI in the second trimester might be a clinically valuable adjunct to ultrasound for the evaluation of CNS anomalies, especially when ultrasound is inconclusive due to maternal obesity.


Subject(s)
Central Nervous System/abnormalities , Magnetic Resonance Imaging/methods , Nervous System Malformations/diagnosis , Prenatal Diagnosis/methods , Adult , Autopsy , Central Nervous System/pathology , Cohort Studies , Female , Fetal Mortality , Fetus/abnormalities , Humans , Nervous System Malformations/mortality , Pregnancy , Pregnancy Trimester, Second , Prospective Studies , Sensitivity and Specificity , Sweden , Ultrasonography, Prenatal , Young Adult
12.
Acta Obstet Gynecol Scand ; 88(6): 654-9, 2009.
Article in English | MEDLINE | ID: mdl-19412801

ABSTRACT

OBJECTIVES: To assess the ascertainment of spina bifida and cleft lip/palate (CLP) in newborns and in fetuses from terminated pregnancies (ToPs) in the Swedish Birth Defects Registry (BDR) and to estimate the true incidences of these two anomalies. DESIGN: Retrospective register study. SETTING: Center for Epidemiology at the Swedish National Board of Health and Welfare, and Uppsala University Hospital. POPULATION: Newborns and fetuses from ToPs with spina bifida (1999-2004) and CLP (1999-2002) in Sweden. METHODS: Data from four registries/sources were used to estimate ascertainment in BDR and incidences of spina bifida and CLP. MAIN OUTCOME MEASURE: Ascertainment, under-ascertainment, and true incidence. RESULTS: For newborns, under-ascertainment of spina bifida and CLP were 6 and 13%, respectively, in BDR after record linkage with the Medical Birth Registry. Ascertainment of cleft palate increased when accompanied by cleft lip. The under-ascertainment of spina bifida in ToPs after 18 gestational weeks was 27%. Ascertainment of CLP in all ToPs and of spina bifida in ToPs before the 18th gestational week could not be estimated. The majority (109/155, 70%) of ToPs with spina bifida occurred before the 18th week. The estimated incidence of spina bifida per 10,000 births was 6.1 (2.4 newborns and 3.7 ToPs) and of CLP 20.1 (18.9 newborns and 1.2 ToPs). CONCLUSION: The ascertainments are relatively high for newborns in BDR, but lower or unknown for ToPs, which has an impact on the surveillance of spina bifida in view of the high proportion of ToPs.


Subject(s)
Cleft Lip/epidemiology , Cleft Palate/epidemiology , Congenital Abnormalities/epidemiology , Registries , Spinal Dysraphism/epidemiology , Abortion, Induced/statistics & numerical data , Female , Humans , Incidence , Infant, Newborn , Pregnancy , Retrospective Studies
13.
Acta Obstet Gynecol Scand ; 85(10): 1208-16, 2006.
Article in English | MEDLINE | ID: mdl-17068680

ABSTRACT

OBJECTIVE: To compare antenatal diagnoses with autopsy findings in pregnancies terminated after ultrasound detection of fetal anomalies. A second aim was to study the quality of antenatal fetal diagnosis over time. DESIGN: Retrospective, multicenter study over two consecutive six-year periods in Uppsala and Stockholm. SETTING: Cases were identified through fetal autopsy reports. SUBJECTS: Three hundred and twenty-eight fetuses from pregnancies terminated between 1992 and 2003 because of ultrasonographically diagnosed anomalies. MAIN OUTCOME MEASURES: The findings at the last ultrasound examination were compared with the autopsy reports. RESULTS: In 299 cases (91.2%) ultrasound findings either exactly matched or were essentially similar to the autopsy findings. In 23 cases (7%) ultrasound findings were not confirmed at autopsy, but the postnatal findings were at least as severe as the antenatal ones. In six cases (1.8%) termination was performed for an anomaly which proved to be less severe than was predicted by ultrasound. The number of such cases was the same in both six-year periods, while the total number of cases increased from 113 in the first to 215 in the second period. Fetal examination provided further diagnostic information in 47% of the cases. In 10% a syndrome was disclosed. CONCLUSION: Termination of pregnancy was not always based on a correct antenatal diagnosis. All fetuses but one from terminated pregnancies had evident anomalies. In six cases (1.8%) the decision to terminate was based on suboptimal prognostic and diagnostic information. Fetal autopsy by an experienced perinatal pathologist is essential to provide a definitive diagnosis.


Subject(s)
Autopsy , Fetus/abnormalities , Ultrasonography, Prenatal , Abnormalities, Multiple/diagnostic imaging , Abnormalities, Multiple/pathology , Abortion, Induced , Adult , Female , Fetus/pathology , Humans , Predictive Value of Tests , Pregnancy , Severity of Illness Index
14.
BMC Womens Health ; 4(1): 1, 2004 Apr 06.
Article in English | MEDLINE | ID: mdl-15068485

ABSTRACT

BACKGROUND: Acute pancreatitis rarely complicates pregnancy. Although most pregnant women with acute pancreatitis have associated gallstones, less common causes such as drugs have been reported. CASE PRESENTATION: We report the case of a 34-year-old woman who underwent medical abortion with mifepristone and gemeprost and received codeine as pain-relief during the induction of abortion. She developed a severe acute necrotizing pancreatitis which required 14 days of intensive care. Other possible etiological factors, i.e. gallstone, alcohol intake and hyperlipidemia, were excluded. CONCLUSIONS: The reported case of acute pancreatitis was most likely drug-induced.

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