Neofunctionalization of an OMT cluster dominates polymethoxyflavone biosynthesis associated with the domestication of citrus.

Polymethoxyflavones (PMFs) are a class of abundant specialized metabolites with remarkable anticancer properties in citrus. Multiple methoxy groups in PMFs are derived from methylation modification catalyzed by a series of hydroxylases and O-methyltransferases (OMTs). However, the specific OMTs that catalyze the systematic O-methylation of hydroxyflavones remain largely unknown. Here, we report that PMFs are highly accumulated in wild mandarins and mandarin-derived accessions, while undetectable in early-diverging citrus species and related species. Our results demonstrated that three homologous genes, CreOMT3, CreOMT4, and CreOMT5, are crucial for PMF biosynthesis in citrus, and their encoded methyltransferases exhibit multisite O-methylation activities for hydroxyflavones, producing seven PMFs in vitro and in vivo. Comparative genomic and syntenic analyses indicated that the tandem CreOMT3, CreOMT4, and CreOMT5 may be duplicated from CreOMT6 and contributes to the genetic basis of PMF biosynthesis in the mandarin group through neofunctionalization. We also demonstrated that N17 in CreOMT4 is an essential amino acid residue for C3-, C5-, C6-, and C3'-O-methylation activity and provided a rationale for the functional deficiency of OMT6 to produce PMFs in early-diverging citrus and some domesticated citrus species. A 1,041-bp deletion in the CreOMT4 promoter, which is found in most modern cultivated mandarins, has reduced the PMF content relative to that in wild and early-admixture mandarins. This study provides a framework for reconstructing PMF biosynthetic pathways, which may facilitate the breeding of citrus fruits with enhanced health benefits.

Supramolecular Polyurethane "Ligaments" Enabling Room-Temperature Self-Healing Flexible Perovskite Solar Cells and Mini-Modules.

Flexible perovskite solar cells (F-PSCs) have emerged as promising alternatives to conventional silicon solar cells for applications in portable and wearable electronics. However, the mechanical stability of inherently brittle perovskite, due to residual lattice stress and ductile fracture formation, poses significant challenges to the long-term photovoltaic performance and device lifetime. In this paper, to address this issue, a dynamic "ligament" composed of supramolecular poly(dimethylsiloxane) polyurethane (DSSP-PPU) is introduced into the grain boundaries of the PSCs, facilitating the release of residual stress and softening of the grain boundaries. Remarkably, this dynamic "ligament" exhibits excellent self-healing properties and enables the healing of cracks in perovskite films at room temperature. The obtained PSCs have achieved power conversion efficiencies of 23.73% and 22.24% for rigid substrates and flexible substrates, respectively, also 17.32% for flexible mini-modules. Notably, the F-PSCs retain nearly 80% of their initial efficiency even after subjecting the F-PSCs to 8000 bending cycles (r = 2 mm), which can further recover to almost 90% of the initial efficiency through the self-healing process. This remarkable improvement in device stability and longevity holds great promise for extending the overall lifetime of F-PSCs.

A Self-Assembled 3D/0D Quasi-Core-Shell Structure as Internal Encapsulation Layer for Stable and Efficient FAPbI3 Perovskite Solar Cells and Modules.

FAPbI3 perovskites have garnered considerable interest owing to their outstanding thermal stability, along with near-theoretical bandgap and efficiency. However, their inherent phase instability presents a substantial challenge to the long-term stability of devices. Herein, this issue through a dual-strategy of self-assembly 3D/0D quasi-core-shell structure is tackled as an internal encapsulation layer, and in situ introduction of excess PbI2 for surface and grain boundary defects passivating, therefore preventing moisture intrusion into FAPbI3 perovskite films. By utilizing this method alone, not only enhances the stability of the FAPbI3 film but also effectively passivates defects and minimizes non-radiative recombination, ultimately yielding a champion device efficiency of 23.23%. Furthermore, the devices own better moisture resistance, exhibiting a T80 lifetime exceeding 3500 h at 40% relative humidity (RH). Meanwhile, a 19.51% PCE of mini-module (5 × 5 cm2) is demonstrated. This research offers valuable insights and directions for the advancement of stable and highly efficient FAPbI3 perovskite solar cells.

Striated preferentially expressed gene deficiency leads to mitochondrial dysfunction in developing cardiomyocytes.

A deficiency of striated preferentially expressed gene (Speg), a member of the myosin light chain kinase family, results in abnormal myofibril structure and function of immature cardiomyocytes (CMs), corresponding with a dilated cardiomyopathy, heart failure and perinatal death. Mitochondrial development plays a role in cardiomyocyte maturation. Therefore, this study investigated whether Speg deficiency ( - / - ) in CMs would result in mitochondrial abnormalities. Speg wild-type and Speg-/- C57BL/6 littermate mice were utilized for assessment of mitochondrial structure by transmission electron and confocal microscopies. Speg was expressed in the first and second heart fields at embryonic (E) day 7.5, prior to the expression of mitochondrial Na+/Ca2+/Li+ exchanger (NCLX) at E8.5. Decreases in NCLX expression (E11.5) and the mitochondrial-to-nuclear DNA ratio (E13.5) were observed in Speg-/- hearts. Imaging of E18.5 Speg-/- hearts revealed abnormal mitochondrial cristae, corresponding with decreased ATP production in cells fed glucose or palmitate, increased levels of mitochondrial superoxide and depolarization of mitochondrial membrane potential. Interestingly, phosphorylated (p) PGC-1α, a key mediator of mitochondrial development, was significantly reduced in Speg-/- hearts during screening for targeted genes. Besides Z-line expression, Speg partially co-localized with PGC-1α in the sarcomeric region and was found in the same complex by co-immunoprecipitation. Overexpression of a Speg internal serine/threonine kinase domain in Speg-/- CMs promoted translocation of pPGC-1α into the nucleus, and restored ATP production that was abolished by siRNA-mediated silencing of PGC-1α. Our results demonstrate a critical role of Speg in mitochondrial development and energy metabolism in CMs, mediated in part by phosphorylation of PGC-1α.

Epigallocatechin-3-gallate restores mitochondrial homeostasis impairment by inhibiting HDAC1-mediated NRF1 histone deacetylation in cardiac hypertrophy.

Decompensated cardiac hypertrophy is accompanied by impaired mitochondrial homeostasis, whether histone acetylation is involved in this process is yet to be determined. The role of HDAC1-mediated NRF1 histone deacetylation was investigated in transverse aortic constriction (TAC)-induced hypertrophy in rats and phenylephrine (PE)-induced hypertrophic cardiomyocytes. Administration of epigallocatechin-3-gallate (EGCG), an inhibitor of HDAC1, restored cardiac function, decreased heart/body weight and fibrosis, increased the ratio of mtDNA/nDNA and the percentage of LysoTracker+ CMs in TAC, compared with TAC without receiving EGCG. In PE-treated hypertrophic H9C2 cells, EGCG attenuated cell hypertrophy and increased LC3B II+MitoTracker+ puncta, as well as the ratio of mtDNA/nDNA. Interestingly, NRF1 but not PGC-1α expression was decreased in TAC- or PE-induced hypertrophic hearts or cells, respectively, while EGCG upregulated both NRF1 and PGC-1α in vitro. EGCG treatment also increased the interaction between PGC-1α and NRF1. In addition to inhibiting HDAC1 expression, EGCG decreased the binding of HDAC1 and increased the binding of acH3K9 or acH3K14 in the promotor regions of PGC-1α and NRF1. In neonatal rat cardiomyocytes, restored NRF1, TFAM and FUNDC1 were abolished by the overexpression of HDAC1. Collectively, data suggest that NRF1 reduction was averted by EGCG via inhibiting HDAC1-mediated histone deacetylation. Acetylation of NRF1 histone may play a key role in maintaining mitochondrial homeostasis associated with cardiac hypertrophy.

Co-Solvent Engineering Contributing to Achieve High-Performance Perovskite Solar Cells and Modules Based on Anti-Solvent Free Technology.

The pinhole-free and defect-less perovskite film is crucial for achieving high efficiency and stable perovskite solar cells (PSCs), which can be prepared by widely used anti-solvent crystallization strategies. However, the involvement of anti-solvent requires precise control and inevitably brings toxicity in fabrication procedures, which limits its large-scale industrial application. In this work, a facile and effective co-solvent engineering strategy is introduced to obtain high- quality perovskite film while avoiding the usage of anti-solvent. The uniform and compact perovskite polycrystalline films have been fabricated through the addition of co-solvent that owns strong coordination capacity with perovskite components , meanwhile possessing the weaker interaction with main solvent . With those strategies, a champion power conversion efficiency (PCE) of 22% has been achieved with the optimal co-solvent, N-methylpyrrolidone (NMP) and without usage of anti-solvent. Subsequently, PSCs based on NMP show high repeatability and good shelf stability (80% PCE remains after storing in ambient condition for 30 days). Finally, the perovskite solar module (5 × 5 cm) with 7 subcells connects in series yielding champion PCE of 16.54%. This strategy provides a general guidance of co-solvent selection for PSCs based on anti-solvent free technology and promotes commercial application of PSCs.

Predictors of attitudes toward potentially having a lesbian, gay, or bisexual child among Chinese heterosexual adults.

Parental acceptance is a robust protective factor for lesbian, gay, or bisexual (LGB) individuals' mental health, yet its predictors have not been frequently studied in China. The present study examined predictors of Chinese heterosexual adults' attitudes toward potentially having an LGB child. Participants were 700 Chinese nationals (37.6% women and 62.4% men) aged 18-64 who identified as exclusively heterosexual and did not have an LGB child. We found that beliefs about the changeability of sexual orientation and beliefs in negative outcomes of being LGB predicted negative attitudes toward having an LGB child in domains of emotion, cognition, and behavior. Moreover, more exposure to LGB individuals predicted reduced disapproval and negative actions as well as increased positive actions. These findings revealed the key factors to changing Chinese people's attitudes toward having an LGB child. Clinical implications for therapists and counselors working with Chinese LGB individuals and their parents are discussed.

The effect of supportive and educational nursing care on quality of life and HE4 gene expression in patients with ovarian cancer.

Ovarian cancer is one of the most common malignancies in women and is also the fifth leading cause of cancer death in women worldwide. In recent years, the survival rate of patients with this disease has been long, and at the same time, more emphasis is on their quality of life. Therefore, the present study was conducted to investigate the effect of supportive and educational care of nurses on the life quality of patients with ovarian cancer. The expression of the HE4 gene was also evaluated as a diagnostic marker of ovarian cancer to assess the role of supportive and educational care of nurses in improving the physical health of these patients. In this study, which was a quasi-experimental study, 45 patients with ovarian cancer participated. The instrument was demographic information and quality of life questionnaires related to Beckman Institute, which were completed in two stages before and after patients' training and support sessions. HE4 gene expression was also assessed by Real-time PCR technique. Finally, the obtained data were analyzed using SPSS software and statistical tests. Based on the results, the mean score of quality of life before the intervention was 51.73 ± 13.91, and after the intervention was 60.46 ± 13.80 (P <0.001). Also, in all four dimensions of quality of life, the mean score of individuals after the intervention increased compared to before the intervention, but this difference was recognized as significant in only two dimensions of physical and mental health (P <0.001). The results of HE4 gene expression also showed that supportive and educational care of nurses had a significant effect on the expression of this gene. Therefore, this study confirmed the positive effect of educational and supportive programs in improving the quality of life of patients with ovarian cancer. In general, the design and implementation of such programs are proposed more widely and based on patients' educational and supportive needs.

Anti-inflammatory effect of luteolin is related to the changes in the gut microbiota and contributes to preventing the progression from simple steatosis to nonalcoholic steatohepatitis.

Increasing intestinal barrier function is one of the basic methods to suppress inflammation in the progression from simple steatosis (SS) to nonalcoholic steatohepatitis (NASH). Luteolin exists widely in vegetables, fruits and natural herbs and has various biological activities, including benefits on nonalcoholic fatty liver disease (NAFLD). However, its regulatory effects on the gut microbiota and involvement in its biological activities remain to be investigated. We fed rats a high-fat diet containing 0.5% luteolin for 12 weeks and determined the effects of luteolin on lipid metabolism, inflammation, and the gut microbiota. Supplementation with luteolin for 12 weeks significantly reduced blood lipids and hepatic lipid levels and improved liver fat accumulation and inflammation. Moreover, supplementation with luteolin led to the significant enrichment of more than 10% of gut bacterial species, which contributed to increase the abundance of ZO-1, reduce intestinal permeability, reduce plasma lipopolysaccharide, and inhibit the TLR4/NF-κB pathway. In summary, the anti-inflammatory effect of luteolin might be related to changes in the gut microbiota and contribute to preventing the progression from SS to NASH. Our research provides new insights into the anti-inflammatory mechanism of luteolin and supports its use as a dietary supplement for NAFLD patients.

Oral contraceptive use in adolescence predicts lasting vulnerability to depression in adulthood.

BACKGROUND: Previous evidence suggests that use of oral contraceptives (OCs), especially during adolescence, may increase women's vulnerability to depression in the short term. Here, we investigate whether women who had first used OC in adolescence show an increased prevalence of depression in the long term. METHODS: We examined 1,236 women in the United States National Health and Nutrition Examination Survey for whom information on depression and age at first OC use was publicly available. We compared women who reported first use of OCs in adolescence to women who had never used OCs and women who had first used OCs in adulthood on 1-year prevalence of major depressive disorder (MDD) assessed by trained interviewers. RESULTS: Compared with women who had used OCs during adolescence, women who had never used OCs were less likely to meet the criteria for MDD within the past year in adulthood [odds ratio (OR) = 0.31, 95% CI = 0.16-0.60], and so were women who only started using OCs in adulthood (OR = 0.54, 95% CI = 0.30-0.95). Third factors that have previously been proposed to explain the relationship between OC use and depression risk such as age at sexual debut, and, importantly, current OC use, did not account for the results in propensity score analyses. CONCLUSIONS: We show a long-term association between adolescent OC use and depression risk in adulthood regardless of current OC use. Our findings suggest that adolescence may be a sensitive period during which OC use could increase women's risk for depression, years after first exposure.

The link between LGBTQ-supportive communities, progressive political climate, and suicidality among sexual minority adolescents in Canada.

Despite supportive structural changes to reduce stigma towards lesbian, gay, and bisexual, transgender, queer, and questioning (LGBTQ) Canadian residents, sexual minority youth still face disparities compared to heterosexual peers. We aimed to characterize LGBTQ-supportive environments and political climates, and examine their links to suicidal behavior among sexual minority adolescents in western Canada. Data were from the 2013 British Columbia Adolescent Health Survey, a cluster-stratified random cross-sectional survey of public school students in BC, Canada; We sampled 2678 self-identified LGB and mostly heterosexual students (69% girls) from 274 schools, representing an estimated provincial population of 24,624 sexual minority students in weighted models. Student reports of past-year suicidal ideation, suicidal attempts, and self-harm behaviors were merged with community-level data assessing diverse aspects of LGBTQ-supportive resources and progressive political climates in communities surrounding the schools. Adjusted multilevel models showed that for sexual minority adolescent girls, higher community LGBTQ-supportiveness predicted marginally significant lower suicidal ideation (aOR = 0.94, 95% CI [0.88, 1.01]) and suicidal attempts (aOR = 0.91, 95% CI [0.83, 1.00]) and significantly lower self-harm behaviors (aOR = 0.91, 95% CI [0.85, 0.98]). Further, progressive political climates predicted marginally significant lower suicidal ideation (aOR = 0.89, 95% CI [0.78, 1.02]) and significantly lower self-harm behaviors (aOR = 0.87, 95% CI [0.77, 0.99]). For sexual minority adolescent boys, no community-level variables were associated with suicidal behavior in adjusted models. Thus, LGBTQ-supportive communities and progressive political climates appear to be protective against suicidal behavior among sexual minority adolescent girls, but not sexual minority adolescent boys.

Sexual Experimentation in Heterosexual, Bisexual, Lesbian/Gay, and Questioning Adolescents From Ages 11 to 15.

To examine adolescent sexuality development, we analyzed data from a British cohort study (N = 5,070), which assessed the same 12-14 sexual activities at ages 11, 12, 13, and 15, and sexual orientation identity at age 15. The sexual activities ranged from low (e.g., cuddling), moderate (e.g., kissing), to high (e.g., sexual intercourse) intensity. We found that most adolescents having sexual activities of low-to-moderate intensity with same-sex individuals also had them with other-sex individuals, and adolescents having other-sex contacts of low intensity often reported them nonexclusively. Furthermore, other-sex and same-sex sexual activities did not reliably distinguish between sexual orientation identities. Sex differences in these phenomena were absent or small. These findings suggest that many adolescents have low-intensity nonexclusive sexual behaviors.

Predictors and Mental Health Benefits of Chosen Name Use among Transgender Youth.

Chosen name use among transgender youth (youth whose gender identities are different than their sex assigned at birth) can be part of the complex process of aligning gender presentation with gender identity and can promote mental health. However, little is known about the factors that predict whether or not transgender youth have a chosen name and outcomes of chosen name use, especially in specific social contexts. We examined, among a sample of 129 transgender youth from three cities in the United States, differences in sociodemographic characteristics and mental health outcomes between transgender youth with and without a chosen name and, among those with a chosen name, predictors and mental health benefits of being able to use a chosen name at home, school, and work. There were few differences between transgender youth with and without a chosen name. Among transgender youth with a chosen name, disclosure of gender identity to supportive family and teachers predicted chosen name use at home and school, respectively. Chosen name use was associated with large reductions in negative health outcomes and relatively smaller improvements in positive mental health outcomes. Our results show that chosen name use is part of the gender affirmation process for some, but not all, transgender youth and is associated with better mental health among transgender youth who adopt a chosen name.

Increased Lactate in Gastric Cancer Tumor-Infiltrating Lymphocytes Is Related to Impaired T Cell Function Due to miR-34a Deregulated Lactate Dehydrogenase A.

BACKGROUND/AIMS: Lactate is one of the products of glycolysis and is a hallmark of the Warburg effect. Glycolysis is found in tumor as well as immune cells. However, the effects of lactate on the function of tumor-infiltrating T cells (TILs) are rarely reported. METHODS: In the present study, we investigated lactate and other glycolysis-related metabolites within TILs of human gastric cancer (GC). Lactate concentration was determined by liquid chromatography-mass spectrometry. The functional effects and clinical relevance of excessive lactate on T cells were investigated in clinical samples, and the mechanism of increased lactate was explored. RESULTS: Lactate was significantly increased in GC TILs and related to decreased T helper (Th)1 cells and cytotoxic T lymphocytes (CTLs). Increased lactate within GC TILs was positively correlated with increased lactate dehydrogenase A (LDH)A. Expression of LDHA in GC TILs was also negatively correlated with percentages of Th1 cells and CTLs. Decreased miR-34a expression in GC TILs was responsible for increased expression of LDHA. A hypoxic tumor environment was responsible for decreased miR-34a and lactate-induced impaired immune function. CONCLUSION: We found that hypoxia decreases miR-34a expression and lose miR-34a regulation on LDHA, thus increasing lactate level within GC TILs and impairing immune function in GC.

Single-Sex Schooling: Friendships, Dating, and Sexual Orientation.

Single-sex schooling has been controversial for decades. The current study investigated the differences in friendships, dating, and past, present, and ideal sexual orientation, between 207 college students who attended single-sex secondary schools and 249 college students who attended coeducational secondary schools in Hong Kong, controlling for personal characteristics such as socioeconomic status. We found that, compared to graduates of coeducational schools, graduates of single-sex schools reported a different gender composition in intimate friendships favoring the same sex, less romantic involvement with other-sex close friends, older age at first date, fewer boyfriends or girlfriends, and more past same-sex sexuality. In contrast, we found no significant differences in the interactions with same-sex versus other-sex friends, most aspects of past or present dating engagement, or self-reported present or ideal sexual orientation. These findings give insight into the interpersonal outcomes of single-sex schooling and fill a gap in previous research which has focused on academic achievement and gender role stereotypes.

Preschool Gender-Typed Play Behavior at Age 3.5 Years Predicts Physical Aggression at Age 13 Years.

Gender differences in play behavior and physical aggression have been consistently reported. Theoretical perspectives concerning evolutionary, social, and social-cognitive mechanisms suggest that male-typical play behavior during childhood increases subsequent physical aggression. The evidence supporting these connections is limited, however. The present study investigated the association between gender-typed play behavior in early childhood and physical aggression in early adolescence using a sample drawn from a longitudinal, population study, the Avon Longitudinal Study of Parents and Children. Based on gender-typed play behavior as measured by the Pre-School Activities Inventory at age 3.5 years, samples of masculine (64 boys, 60 girls), feminine (80 boys, 66 girls), and randomly selected control children (55 boys, 67 girls) were recruited at age 13 years and administered the Reinisch Aggression Inventory. After controlling for a range of sociodemographic variables, maternal characteristics, and behavioral problems, including hyperactivity and conduct problems at age 3.5, significant group differences in physical aggression at age 13 were found among children classified as masculine, control, and feminine at age 3.5. Masculine children exhibited significantly more physical aggression than control children or feminine children, and control children exhibited significantly more physical aggression than feminine children. The association between gender-typed play behavior and physical aggression was not moderated by sex. These results suggest that the degree of childhood gender-typed play behavior independently predicts the degree of physical aggression at adolescence in boys and in girls.

The application of ceramsite ecological floating bed in aquaculture: its effects on water quality, phytoplankton, bacteria and fish production.

In recent years, biological floating bed technology has been applied increasingly in aquaculture ponds. In this study we developed a novel floating bed made from ceramsite and studied its effect on water quality, phytoplankton, bacteria and fish growth. Water quality was effectively regulated and controlled in ceramsite floating bed (CFB) ponds with an average transparency of 23.18 cm, ammonia nitrogen (NH4+-N) of 2.30 mg L-1, total nitrogen (TN) of 5.09 mg L-1 and total phosphate (TP) of 1.32 mg L-1 which are lower than in control ponds without CFB. Increased phytoplankton species diversity, bacterial number, metabolic activity and microbial diversity was observed with CFB. At the end of growth stage, feed conversion ratio (FCR) was reduced with a total fish yield of 14,838 kg ha-1 at a survival rate of 77.2% in CFB ponds, which is significantly higher than control (P < 0.05). These results emphasize the potential of ecological floating bed to improve water quality, microalgal diversity, reduce the risk of harmful algal blooms and increase the number, activity and diversity of microorganisms as well as fish yield.

The safety of simultaneous cranioplasty and shunt implantation.

BACKGROUND: A large cranial defect combined with hydrocephalus is a frequent sequela of decompressive craniectomy (DC) performed to treat malignant intracranial hypertension. Currently, many neurosurgeons perform simultaneous cranioplasty and shunt implantation on such patients, but the safety of this combined procedure remains controversial. METHODS: We retrospectively evaluated 58 patients treated via cranioplasty and shunt implantation after DC. Twenty patients underwent simultaneous procedures (simultaneous operation group) and 38 underwent staged procedures (staged operation group). We collected and analysed demographic data, information on disease histories, and clinical findings. RESULTS: The overall complication rate was 19%. The two groups did not significantly differ regarding the all-complication (30% vs. 13%), bleeding complication (0% vs. 5%), or treatment failure (15% vs. 3%) rates. However, the rate of surgical site infection/incision healing problems (25% vs. 3%) and the re-operation rate (20% vs. 3%) were significantly higher in the simultaneous operation group. CONCLUSION: Patients undergoing simultaneous cranioplasty/shunt implantation may be at a higher risk of infectious complications than those undergoing staged operations.

A novel growth method for diatom algae in aquaculture waste water for natural food development and nutrient removal.

Diatom algae are known to play an important role as primary producers in many diverse ecosystems, including artificial aquaculture ponds where they also aid in maintaining water quality by consuming excess nutrients. But factors influencing their growth are still poorly understood. In the present study the effect of micronutrients, N:P ratio and silica concentration on benthic diatom Synedra sp. grown in fish pond waste water was studied along with nutrient removal efficiency. We have studied nine different treatments, of which addition of micronutrient mixture Nualgi along with adjusted N:P to 6:1 resulted in highest cell density, followed by silicate enrichment, whereas only N:P adjustment and Nualgi addition had no significant effect on diatom growth. At the end of the growth experiment, the N removal efficiencies of treatment groups (50.23%-65.44%) were significantly higher (P < 0.05) than that of the control group (43.56%), whereas phosphate removal efficiency was significantly higher (P < 0.05) with Nualgi and N:P adjustment (53.37%-68.98%). The silicate consumption was significantly higher in the control group, at 63.87%, than in other experimental groups. These results will give us a new insight into important factors influencing beneficial algae growth and simultaneous nutrient removal from aquaculture waste water.

In Search of Emerging Same-Sex Sexuality: Romantic Attractions at Age 13 Years.

Sex-typed behavior in childhood is significantly related to sexual orientation in adulthood. In addition, same-sex attractions in early adolescence are more non-exclusive than in adulthood and can differ from later same-sex orientations. However, little research has focused on romantic attractions as they emerge during early adolescence. Drawing a sample from the Avon Longitudinal Study of Parents and Children (197 girls, 204 boys), the current study examined whether same-sex romantic attractions at age 13 years were exclusive, and whether they were predicted by sex-typed behavior at age 3.5 years. No young adolescents in this sample reported exclusive same-sex attractions, and increased same-sex attractions were not significantly related to reduced other-sex sexualities. Childhood sex-typed behavior did not significantly predict early same-sex attractions, suggesting that early same-sex attractions differ from later same-sex orientations. The current study highlights the importance of studying the development of sexuality beginning prior to adulthood.