Singlet-to-triplet intersystem crossing (ISC) in organic molecules is intimately connected with their geometries: by modifying the molecular shape, symmetry selection rules pertaining to spin-orbit coupling can be partially relieved, leading to extra matrix elements for increased ISC. As an analog to this molecular design concept, the study finds that the lattice symmetry of supramolecular polymers also defines their triplet formation efficiencies. A supramolecular polymer self-assembled from weakly interacting molecules is considered. Its 2D oblique unit cell effectively renders it as a coplanar array of 1D molecular columns weakly bound to each other. Using momentum-resolved photoluminescence imaging in combination with Monte Carlo simulations, the study found that photogenerated charge carriers in the supramolecular polymer predominantly recombine as spin-uncorrelated carrier pairs through inter-column charge transfer states. This lattice-defined recombination pathway leads to a substantial triplet formation efficiency (≈60%) in the supramolecular polymer. These findings suggest that lattice symmetry of micro-/macroscopic structures relying on intermolecular interactions can be strategized for controlled triplet formation.

There are a few comprehensive genetic studies on autism spectrum disorders (ASD) in India. Children of multiple births are valuable for genomics studies of complex disorders such as ASD. We report whole-exome sequencing (WES) in a triplet family in which only one among the triplet has ASD. The objective of this study was to identify potential candidate genes for ASD. Exome DNA was enriched using a twist human customized core exome kit, and paired-end sequencing was performed. Proband-specific de novo variants included 150 single nucleotide polymorphisms (SNPs) and 74 indels. Thirteen SNPs were in exonic regions, 7 of them being missense variations. Seventeen variants were previously reported in ASD. Genes harboring variants have functions in the development and maintenance of the central nervous system and are enriched in biological processes involving cell adhesion. This is the first comprehensive genetic study of a monozygotic triplet in ASD.

BACKGROUND: The worldwide occurrence of triplet pregnancy is estimated to be 0.093%, with a natural incidence of approximately 1 in 8000. This study aims to analyze the neonatal health status and birth weight discordance (BWD) of triplets based on chorionicity from birth until discharge.
METHODS: This was a retrospective study. We reviewed a total of 136 triplet pregnancies at our tertiary hospital between January 1, 2001, and December 31, 2021. Maternal and neonatal outcomes, inter-triplet BWD, neonatal morbidity, and mortality were analyzed.
RESULTS: Among all cases, the rates of intrauterine death, neonatal death, and perinatal death were 10.29, 13.07, and 24.26%, respectively. Thirty-seven of the cases resulted in fetal loss, including 13 with fetal anomalies. The maternal complications and neonatal outcomes of the 99 triplet pregnancies without fetal loss were compared across different chorionicities, including a dichorionic (DC) group (41 cases), trichorionic (TC) group (37 cases), and monochorionic (MC) group (21 cases). Neonatal hypoproteinemia (P < 0.001), hyperbilirubinemia (P < 0.019), and anemia (P < 0.003) exhibited significant differences according to chorionicity, as did the distribution of BWD (P < 0.001). More than half of the cases in the DC and TC groups had a BWD < 15%, while those in the MC group had a BWD < 50% (47.6%). TC pregnancy decreased the risk of neonatal anemia (adjusted odds ratio [AOR] = 0.084) and need for blood transfusion therapy after birth (AOR = 0.119). In contrast, a BWD > 25% increased the risk of neonatal anemia (AOR = 10.135) and need for blood transfusion after birth (AOR = 7.127). TC pregnancy, MCDA or MCTA, and BWD > 25% increased neonatal hypoproteinemia, with AORs of 4.629, 5.123, and 5.343, respectively.
CONCLUSIONS: The BWD differed significantly according to chorionicity. Additionally, TC pregnancies reduced the risk of neonatal anemia and need for blood transfusion, but increased the risk of neonatal hypoproteinemia. In contrast, the BWD between the largest and smallest triplets increased the risk of neonatal anemia and the need for blood transfusion. TC pregnancy, MCDA or MCTA, and BWD > 25% increased the risks of neonatal hypoproteinemia. However, due to the limited number of triplet pregnancies, further exploration of the underlying mechanism is warranted.

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OBJECTIVE: Triplet pregnancies involve several complications, the most important being prematurity as virtually all triplets are born preterm. We conducted this study to compare the outcomes of reduced vs. non-reduced triplet pregnancies managed in the largest tertiary hospital in Finland.
METHODS: This was a retrospective cohort study in the Helsinki University Hospital during 2006-2020. Data on the pregnancies, parturients and newborns were collected from patient records. The fetal number, chorionicity and amnionicity were defined in first-trimester ultrasound screening. The main outcome measures were perinatal and neonatal mortality of non-reduced triplets, compared to twins and singletons selectively reduced of triplet pregnancies.
RESULTS: There were 57 initially triplet pregnancies and 35 of these continued as non-reduced triplets and resulted in the delivery of 104 liveborn children. The remaining 22 cases were spontaneously or medically reduced to twins (9) or singletons (13). Most (54.4 %) triplet pregnancies were spontaneous. There were no significant differences in gestational age at delivery between triplets (mean 33+0, median 34+0) and those reduced to twins (mean 32+5, median 36+0). The survival at one week of age was higher for triplets compared to twins (p<0.00001).
CONCLUSIONS: Most pregnancies continued as non-reduced triplets, which were born at a similar gestational age but with a significantly higher liveborn rate compared to those reduced to twins. There were no early neonatal deaths among cases reduced to singletons. Prematurity was the greatest concern for multiples in this cohort, whereas the small numbers may explain the lack of difference in gestational age between these groups.

OBJECTIVE: Multiple pregnancies involve several complications, most often prematurity, but also higher anomaly rates. Reducing fetuses generally improves pregnancy outcomes. We conducted this study to evaluate the obstetrical and neonatal results after multifetal pregnancy reduction (MFPR) in the largest tertiary hospital in Finland.
METHODS: This retrospective cohort study included all MFPR managed in Helsinki University Hospital during a 13 year period (2007-2019). Data on pregnancies, parturients and newborns were collected from patient files. The number of fetuses, chorionicities and amnionicities were defined in first-trimester ultrasound screening.
RESULTS: There were 54 MFPR cases included in the final analyses. Most often the reduction was from twins to singletons (n=34, 63 %). Majority of these (25/34, 73.5 %) were due to co-twin anomaly. Triplets (n=16, 29.6 %) were reduced to twins (n=7, 13 %) or singletons (n=9, 16.7 %), quadruplets (n=2, 3.7 %) and quintuplets (n=2, 3.7 %) to twins. Most (33/54, 61.1 %) MFPR procedures were done by 15+0 weeks of gestation. There were six miscarriages after MFPR and one early co-twin miscarriage. In the remaining 47 pregnancies that continued as twins (n=7, 14.9 %) or singletons (n=40, 85.1 %) the liveborn rate was 90 % for one fetus and 71.4 % for two fetuses.
CONCLUSIONS: Most MFPR cases were pregnancies with an anomalous co-twin. The whole pregnancy loss risk was 11.1 % after MFPR. The majority (70.6 %) of twins were spontaneous, whereas all quadruplets, quintuplets, and 56.3 % of triplets were assisted reproductive technologies (ART) pregnancies. Careful counselling should be an essential part of obstetrical care in multiple pregnancies, which should be referred to fetomaternal units for MFPR option.

Treatment options have expanded rapidly and widely in the past two decades for patients with multiple myeloma. Triplet novel agent-based induction regimens have been accepted as the standard practice wordwide over the last decade both for transplant-eligible and non-eligible patients. The addition of anti-CD38 monoclonal antibodies as part of quadruplet regimens has led to even deeper and longer-lasting responses. The impressive results shown by the quadruplets havebeen practice-changing where accessible in recent years. Chimeric antigen receptor T cell therapy and bispecific antibodies are being tested in the upfront setting and have the potential to once again shift the paradigm of treatment of newly diagnosed MM.

The standards of care for the initial treatment of patients with newly diagnosed multiple myeloma (NDMM) who are eligible for high-dose melphalan and autologous stem cell transplantation (HDM-ASCT) include highly active triplet and quadruplet regimens based on proteasome inhibitors, immunomodulatory drugs, and monoclonal antibodies. These regimens are resulting in improved outcomes and increasingly high rates of minimal residual disease (MRD)-negative responses without HDM-ASCT as part of the upfront therapy. Furthermore, recent randomized studies have shown that, while transplant-based approaches as a frontline therapy result in significantly longer progression-free survival compared to non-transplant approaches, this has not translated into an overall survival benefit. Given these developments, and in the context of the treatment burden of undergoing HDM-ASCT, in addition to the acute toxicities and long-term sequelae of HDM, which are associated with the genotoxicity of melphalan, there is an increasing rationale for considering deferring upfront HDM-ASCT in select transplant-eligible patients and saving it as a treatment option for later salvage therapy. Here, we review the latest clinical trial data on upfront or deferred HDM-ASCT and on the activity of quadruplet induction regimens, including rates of MRD-negative responses, and summarize emerging treatment approaches in the upfront setting such as the use of MRD-directed therapy and alternatives to HDM-ASCT.

Multiple pregnancies are associated with significant maternal, fetal, and neonatal risks, including prematurity, low birth weight, pre-eclampsia, anemia, postpartum hemorrhage, intrauterine growth restriction, neonatal morbidity, and increased neonatal and infant mortality rates. Assisted reproductive technology (ART) treatments should prioritize efforts to reduce such events, resisting patient demand for the transfer of multiple embryos at each transfer to increase success rates. Extended culture, embryo selection, and single blastocyst transfer can mitigate the risk of high-order multiple pregnancies. Intriguingly, elective single-embryo transfer (eSET) greatly reduces, but does not completely eliminate, the likelihood of multiple gestations. The occurrence of monozygotic twinning (MZT) gives rise to identical twins. It is more prevalent in women undergoing in vitro fertilization (IVF) compared with natural conception. In fact, the reported risks of monozygotic twinning in IVF and natural conception are 1.7 and 0.4%, respectively. The factors suspected to increase the risk of MZT in IVF are multiple embryo transfer, micromanipulation, and extended in vitro culture. Determining chorionicity and amnionicity is crucial in the assessment of multiple pregnancies during the first-trimester ultrasound examination. Dichorionic twins result from embryo splitting within 3 days after fertilization, while monochorionic twins occur when the splitting takes place between 4 and 8 days after fertilization. These timings are suggested by observations carried out in natural pregnancies. In ART, there is evidence of dichorionic twins derived from single embryo transfer (SET). Here, we report a case of dichorionic diamniotic triplets after a single blastocyst transfer occurred in our center. To our knowledge, this is the first case documented so far.

The introduction of assisted reproductive technology and the trend of increasing maternal age at conception have contributed to a significant rise in the incidence of multiple pregnancies. Multiple pregnancies bear several inherent risks for both mother and child. These risks increase with plurality and type of chorionicity. Multifetal pregnancy reduction is the selective abortion of ≥1 fetuses to improve the outcome of the remaining fetus(es) by decreasing the risk of premature birth and other complications.
This study aimed to compare birth outcomes of trichorionic triplets reduced to twins with those of trichorionic triplets and primary dichorionic twins. The added value of this study is the comparison with an additional control group, namely primary dichorionic twins.
This was a retrospective cohort study. Data from January 1990 to November 2016 were collected from the East Flanders Prospective Twin Survey, one of the largest European multiple birth registries. A total of 85 trichorionic triplet pregnancies (170 neonates) undergoing multifetal pregnancy reduction to twins were compared with 5093 primary dichorionic twin pregnancies (10,186 neonates) and 104 expectantly managed trichorionic triplet pregnancies (309 neonates). The assessed outcomes were gestational age at delivery, birthweight, and small for gestational age.
Pregnancy reduction from triplets to twins was associated with higher birthweight (+365.44 g; 95% confidence interval, 222.75-508.14 g; P<.0001) and higher gestational age (1.7 weeks; 95% confidence interval, 0.93-2.46; P<.0001) compared with ongoing trichorionic triplets after adjustment for sex, parity, method of conception, birth year, and maternal age. A trend toward lower risk of small for gestational age was observed. Reduced triplets had, on average, lower birthweight (-263.12 g; 95% confidence interval, -371.80 to -154.44 g; P<.0001) and lower gestational age (-1.13 weeks; 95% confidence interval, -1.70 to -0.56; P=.0001) compared with primary twins. No statistically significant difference was observed between primary twins and reduced triplets that reached 32 weeks of gestation.
Multifetal pregnancy reduction from trichorionic triplets to twins significantly improved birth outcomes. This suggests that multifetal pregnancy reduction of trichorionic triplets to twins is medically justifiable. However, the birth outcomes of primary twins before 32 weeks of gestation are still better than those of reduced triplets. The process of multifetal pregnancy reduction includes at least 1 fetal death by definition, and thus prevention of higher-order pregnancies is preferable.