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At least 919 records · Page 51Linked to original sources

Triplet pregnancy. A 10-year review of cases at Baragwanath Hospital.

A series of 61 triplet pregnancies delivered in the Baragwanath Hospital for the 10 years 1967 - 1976 is analysed, the incidence being 1 : 2 789 deliveries. The average maternal age was 29,6 years, and average parity 3,7; 60% had had adequate antenatal care, a figure significantly higher than that for the local normal pregnant population. The vast majority of the patients had vaginal deliveries, although the proportion of manipulative procedures was high. The duration of labour was strikingly short in most instances. The fetal outcome was impressively good, although somewhat better with the second triplet than with the other two. This indicates that, in spite of the recent tendency towards liberal use of caesarean sections in these patients, a careful and appropriate vaginal approach has its merits.

Adolescent↗

[Antepartal diagnosis of an acardius in a triplet pregnancy using ultrasound].

In fetal anomalies we can follow the course by repeated ultrasound examinations and so decide the therapy. For collection of experience all rare cases should be published. Beginning in 25th gestational week we observed a triplet pregnancy, in which one fetus was a severe malformed acardius. Fetus I has been separated with an own placenta and was developing well. Fetus II had to supply the acardius with circulating blood and therefore it retarded beginning in the 28th week. Fetus III was the malformed acardius. Beginning in the 28th week it began to grow rapidly. Caused by this fact and an increasing hydramnios pregnancy was terminated by spontaneous delivery in 31th week. The normal fetus I (1320 g) survived. The retarded fetus II (830 g) died postnataly. The diagnosis of an acardius monster (triplet III, 2090 g) was confirmed by autopsy. Good collaboration with the pathologist is of great value, because he can show the clinician the degree of precision of his antenatal diagnosis.

Abnormalities, Severe Teratoid↗

Outcome of pregnancy in 31 triplet gestations.

The course of gestation and labor and the outcome of 31 triplet pregnancies were analyzed. Early diagnosis is very important for improving the rate of fetal salvage in multiple pregnancy. The outcome of triplet pregnancies was better in the group of patients with induced ovulation than in the group with spontaneous ovulation. The most frequent antenatal complications were preterm labor (97%), pregnancy-induced hypertension (46%), and anemia (20%). In this series the favorable results were due to earlier diagnosis, prolonged hospitalization, and planned delivery, usually by cesarean section.

Adult↗

Triplet pregnancies.

Fifteen triplet gestations delivered over 23 years beginning with 1954 are reviewed. The mortality rate was 7.1% in the gestation period of 28 weeks or more. This mortality rate compares favorably with the 15% to 50% rate reported in the literature. Among the third babies of each set, there was a mortality rate of 14.3%, again confirming the high mortality rate reported in the literature. Morbidity in triplet gestations was equally elevated. Although the data do not suggest what the best method of delivery is, the increased morbidity and mortality for the third baby of the set delivered vaginally implies that a more liberal use of cesarean section may reduce the potential risks for that baby. Also, among the eight cesarean sections performed in pregnancies at 28 weeks of gestation or more that have been reported in the literature, none of the babies died during the neonatal period.

Apgar Score↗

[Follow-up of mothers of triplets 2 years after delivery. Results of a longitudinal study].

The aim of the study was to assess the health of mothers of triplets, two years after delivery. As part of a longitudinal study, 11 mothers having delivered consecutively in clinique Baudelocque were interviewed at home. They reported considerable fatigue and stress. Four women suffered with anxiety and depressive symptoms and three of them used psychotropic medication. Considering the possible consequences of maternal depression upon the child development, one third of the children in the study are particularly at risk. These results showed that the difficulties experienced by mothers of triplets persisted and remained important even under favourable medical and social circumstances.

Child Development↗

Transverse versus longitudinal uterine incision in cesarean delivery of triplets.

It is commonly accepted that cesarean section is the preferred mode of delivery of triplets. The present study was performed to evaluate maternal complications and neonatal outcome in 21 women operated on by a transverse lower segment incision as compared to 8 parturients who underwent surgery by a longitudinal uterine incision. There was no significant difference in mean gestational age at delivery, mean weight of the newborns, Apgar scores, perinatal mortality rates, or intraoperative or postpartum hemorrhage incidence between the two groups. Thus, a transverse lower segment uterine incision should be used in triplet deliveries to increase the chances of a normal vaginal delivery in the future.

Apgar Score↗

[Monozygotic triplet pregnancy after transfer of frozen embryos].

We report a case of monozygotic triplet pregnancy after transfer of 3 frozen thawed embryos. The pregnancy ended by the birth of 3 healthy normal boys and all the analysis showed that it was really a monochorionic triamniotic triplet pregnancy, that as far as we know is the first reported one induced by frozen thawed technics. We shall discuss: the etiology of monozygotic pregnancies after IVF; the sonographic diagnosis of placentation; the obstetrical care which allowed the birth of 3 healthy normal boys.

Adult↗

[Myelodysplasia in triplet pregnancy].

INTRODUCTION: The myelodysplastic syndromes (MSD) are a group of hematologic disorders that manifest dysplastic hematopoiesis and usually a hypercellular bone marrow. Ineffective hematopoiesis leads to haematologic failure in these syndromes. The MDS are a rare event during pregnancy although the exact incidence is unknown it is likely to be less than that for leukaemia. CLINICAL REPORT: The case, a 29 year old woman, presented during 23rd week of her first, triplet, pregnancy with symptoms of anemia and thrombocytopenia is described. DISCUSSION: The pathogenetic aspect and diagnostic management is discussed, underlined especially under the point of view of the triplet pregnancy. It is suggested that the association of myelodysplastic syndromes during pregnancy is coincidental and that acute leukemia evolves in a majority of these cases. Furthermore, refractory macrocytic anemias in pregnancy need to be carefully evaluated for a primary myelodysplastic state.

Adult↗

Twin reversed arterial perfusion sequence in conjoined, acardiac, acephalic twins associated with a normal triplet. A case report.

BACKGROUND: Twin reversed arterial perfusion (TRAP) sequence and development of an acardiac monster is a rare event. Even more rare are conjoined acardiac, acephalic twins complicating a triplet pregnancy with TRAP sequence. The mortality for the acardius is 100%, and morbidity for the normal, pump fetus is 50%. The morbidity of the pump twin or triplet is attributed mostly to in utero congestive heart failure. CASE: A 24-year-old woman, gravida 1, para 0, at 35 weeks' intrauterine pregnancy, gave birth via low transverse cesarean section to a normal female and a pair of conjoined, acardiac, acephalic, pelvipagus twins. CONCLUSION: The diagnosis of acardius in multiple gestation pregnancy, with no fetal heart tone on ultrasound, must be ruled out in every case so that proper counseling, management and avoidance of complications in these patients can be achieved.

Abnormalities, Multiple↗

Lack of expansion of triplet repeats in the FMR1, FRAXE, and FRAXF loci in male multiplex families with autism and pervasive developmental disorders.

Sib, twin, and family studies have shown that a genetic cause exists in many cases of autism, with a portion of cases associated with a fragile X chromosome. Three folate-sensitive fragile sites in the Xq27-->Xq28 region have been cloned and found to have polymorphic trinucleotide repeats at the respective sites; these repeats are amplified and methylated in individuals who are positive for the different fragile sites. We have tested affected boys and their mothers from 19 families with two autistic/PDD boys for amplification and/or instability of the triplet repeats at these loci and concordance of inheritance of alleles by affected brothers. In all cases, the triplet repeat numbers were within the normal range, with no individuals having expanded or premutation-size alleles. For each locus, there was no evidence for an increased frequency of concordance, indicating that mutations within these genes are unlikely to be responsible for the autistic/PDD phenotypes in the affected boys. Thus, we think it is important to retest those autistic individuals who were cytogenetically positive for a fragile X chromosome, particularly cases where there is no family history of the fragile X syndrome, using the more accurate DNA-based testing procedures.

Autistic Disorder↗

Identification of Triplet States in Carotenoids by Intracavity Absorption Spectroscopy and Measurements of Delayed Fluorescence.

Owing to the low quantum yield of phosphorescence, triplet states of carotenoids have been very difficult to identify. These states can be characterized by intracavity absorption spectroscopy, which allows the direct measurement of the spin-forbidden singlet-triplet transitions in low concentrated solutions, and by delayed fluorescence measurements.

Journal Article↗

Triplet anisotropy decay measurements of DNA internal motion.

Triplet anisotropy decay techniques have been used to measure the internal flexibility and overall rotational motions of DNA over a time range of 15 ns to 200 microseconds. Nearly monodisperse DNA fragments with lengths varying from 65 to 600 base pairs were studied using the intercalating dye methylene blue as a triplet probe. The slow end-over-end tumbling of short DNA fragments (less than 165 base pairs) is as predicted for a rigid rod. As expected, a longer DNA fragment (600 base pairs) experiences slow segmental motions of its helix axis. At the earliest times, anisotropy decays more rapidly than expected for a rigid rod, suggesting that, when it is bound, methylene blue monitors fast internal motions of the helix. Since the rod-like end-over-end tumbling rules out fast bending motions (for short DNA fragments), the fast components of DNA anisotropy decay must be due to twisting motions of the helix, occurring with a time constant near 50 ns. The same techniques were used to measure the conformational flexibility of DNA in the nucleosome. It is concluded that, when the DNA helix is wrapped to form a nucleosome, it experiences substantial internal flexibility, occurring with a time constant near 30 ns. The amplitude and time-scale of this motion appear to be similar to that seen in the uncomplexed DNA helix.

Animals↗

A variant of type II von Willebrand disease with an abnormal triplet structure and discordant effects of protease inhibitors on plasma and platelet von Willebrand factor structure.

We have characterized the plasma and platelet von Willebrand factor (vWf) multimeric structure of a patient with von Willebrand disease (vWd) as having a long bleeding time, no aggregation of her platelet-rich plasma (PRP) to ristocetin, and very low plasma and platelet von Willebrand antigen (vWf Ag) and vWf activity. The abnormalities of the plasma and platelet vWf have not been previously described. In particular, the patient's plasma and platelet vWf lacked the intermediate and largest vWf multimers and the slowest migrating minor band (band 1) of the triplet was markedly diminished compared to the major band (band 2) and the fastest migrating band of the triplet (band 3). A similar multimeric structure was seen in the platelet vWf. Collection of the patient's blood in protease inhibitors prior to the analysis of the platelet and plasma vWf structure revealed that the plasma vWf multimeric structure did not change, while the patient's platelet vWf showed a marked change with the appearance of the intermediate and large multimers and almost total disappearance of the abnormal multimeric structure. Direct comparison of this patient's plasma with previously reported cases of type IIA, IIC, and IID revealed marked differences in their multimeric organization compared to our patient. Employing the presently accepted convention, we have designated this variant type of vWd type IIG.

Blood Platelets↗

Intramolecular triplet energy transfer in donor-acceptor molecules linked by a crown ether bridge.

Bichromophoric compounds BP-C-NP and BP-C-NBD were synthesized with benzophenone chromophore (BP) as the donor, and 2-naphthyl (NP) and norbornadiene group (NBD) as the acceptor, respectively. Their intramolecular triplet energy transfer was examined. The bridges linking the donor and acceptors in these molecules involve a crown ether moiety complexing a sodium ion. Phosphorescence quenching, flash photolysis and photosensitized isomerization experiments indicate that intramolecular triplet energy transfer occurs with rate constants of about 3.3 x 10(5) and 4.8 x 10(5) s(-1) and efficiencies of about 33 and 42 % for BP-C-NP and BP-C-NBD, respectively. Theoretical calculations indicate that these molecules adopt conformations below room temperature which allow their two-end chromophores conducive to through-space energy transfer.

Journal Article↗

Alpha-carbonyl substituent effect on the lifetimes of triplet 1,4-biradicals from Norrish-Type-II reactions.

Triplet 1,4-biradicals were generated by Norrish-Type-II hydrogen transfer from alpha-heteroatom-substituted beta-branched butyrophenones 1-6 and detected by laser flash absorption measurements. For three oxy-substituted compounds 2-4 (R(alpha)=OH, OCOMe, OCOOEt) comparable lifetimes were determined in acetonitrile (roughly 1.5 micros). In benzene, divergent trends were observed: for the hydroxy compound 2 a lower lifetime of 790 ns was determined, whereas for 3 and 4 the lifetimes increased to 4.9 micros. Photolyses of the alpha-amino-substituted compounds 1 and 6 resulted in transient species with significant lower lifetimes (for 1 160 ns in benzene and 450 ns in acetonitrile; for 6 <100 ns in both solvents). The mesyloxy substrate 5 undergoes rapid C-O bond cleavage upon photolysis and no transient triplet species were detected. Computational (UB3 LYP/6-31G* and natural don orbital (NBO) analyses) results supported the assumption of a negative hyperconjugative interaction strongly stabilizing alpha-oxy-substituted over alpha-amino-substituted radicals.

Journal Article↗

C-O-bond cleavage of esters with a naphthyl group in the higher triplet excited state during two-color two-laser flash photolysis.

A C-O-bond cleavage of esters having a naphthyl group, NpCO-OR and RCO-ONp (Np=alpha- and beta-naphthyl ((alpha)Np and (beta)Np, respectively), R=Ph and Me), was found during the two-color two-laser flash photolysis in acetonitrile. The C-O-bond cleavage occurred when NpCO-OR and RCO-ONp were excited to the singlet excited states (S1). On the other hand, no reaction occurred from the lowest triplet excited states (T1). When NpCO-OR(T1) and RCO-ONp(T1) were excited to the higher triplet excited states (Tn) using the second laser during the two-color two-laser flash photolysis, the C-O-bond cleavage occurred. The C-O-bond cleavage quantum yield (Phi) was estimated from the plots of the T1-state esters disappeared within a laser flash versus the second laser intensities. The C-O-bond cleavage in (beta)NpCO-OPh(Tn) occurred more efficiently than in (alpha)NpCO-OPh(Tn) and that in PhCO-O(beta)Np(Tn) occurred more efficiently than in PhCO-O(alpha)Np(Tn). The Phi value for ester with Ph and beta-Np groups was larger than that for ester with Ph and alpha-Np groups. The Phi value for MeCO-O(alpha)Np(Tn) was similar to those for PhCO-ONp(Tn), while that for MeCO-O(beta)Np(Tn) was much smaller than those for PhCO-ONp(Tn) and MeCO-O(alpha)Np(Tn). On the other hand, no C-O-bond cleavage was observed in NpCO-OMe(Tn). The Phi value depended on the characters of the groups (Np, Ph, and Me) on the ester. Whether R is Ph or Me with or without pi electron, respectively, is important for the C-O-bond cleavage. In other words, electronic delocalization of the T(n) state including Np and ester groups is necessary for the occurrence of the C-O-bond cleavage in NpCO-OR(Tn) and RCO-ONp(Tn).

Journal Article↗

Diastereomeric discrimination in the lifetimes of Norrish Type II triplet 1,4-biradicals and stereocontrolled partitioning of their reactivity (Yang cyclization versus Type II fragmentation).

The stereochemistry at C2 and C3 carbons controls the partitioning of triplet 1,4-biradicals of ketones 2 among various pathways. Differences in the major reaction pathways, for example, cyclization (syn) and fragmentation (anti), adopted by the diastereomeric 1,4-radicals of ketones 2 have permitted unprecedented diastereomeric discrimination in their lifetimes to be observed by nanosecond laser flash photolysis. From quantum yield measurements and transient lifetime data, the absolute rate constants for cyclization and fragmentation of a pair of diastereomeric triplet 1,4-biradicals have been determined for the first time.

Journal Article↗