High-efficiency and thermally stable FACsPbI3 perovskite photovoltaics.

α-FA1-xCsxPbI3 is a promising absorber material for efficient and stable perovskite solar cells (PSCs)1,2. However, the most efficient α-FA1-xCsxPbI3 PSCs require the inclusion of methylammonium chloride (MACl) additive3,4, which generates volatile organic residues (i.e., MA) that limit device stability at elevated temperatures5. To date, the highest certified power-conversion efficiency (PCE) of α-FA1-xCsxPbI3 PSCs without MACl was only ~24% (ref.6,7), and has yet to exhibit any stability advantages. Here, we identify interfacial contact loss caused by the Cs+ accumulation for the conventional α-FA1-xCsxPbI3 PSCs, which deteriorates the device performance and stability. Through in-situ GIWAXS analysis and DFT calculations, we demonstrate an intermediate phase-assisted crystallization pathway enabled by acetate surface coordination to fabricate high-quality α-FA1-xCsxPbI3 film, without using MA-additive. We herein report a certified stabilized power output (SPO) efficiency of 25.94% and a reverse-scanning PCE of 26.64% for α-FA1-xCsxPbI3 PSCs, exhibiting negligible contact losses and enhanced operational stability. The devices retain >95% of their initial PCEs after over 2,000 hours operating at maximum power point under 1 sun, 85 °C, and 60% relative humidity (ISOS-L-3).

Synthesis-on-substrate of quantum dot solids.

Perovskite light-emitting diodes (PeLEDs) with an external quantum efficiency exceeding 20% have been achieved in both green and red wavelengths1-5; however, the performance of blue-emitting PeLEDs lags behind6,7. Ultrasmall CsPbBr3 quantum dots are promising candidates with which to realize efficient and stable blue PeLEDs, although it has proven challenging to synthesize a monodispersed population of ultrasmall CsPbBr3 quantum dots, and difficult to retain their solution-phase properties when casting into solid films8. Here we report the direct synthesis-on-substrate of films of suitably coupled, monodispersed, ultrasmall perovskite QDs. We develop ligand structures that enable control over the quantum dots' size, monodispersity and coupling during film-based synthesis. A head group (the side with higher electrostatic potential) on the ligand provides steric hindrance that suppresses the formation of layered perovskites. The tail (the side with lower electrostatic potential) is modified using halide substitution to increase the surface binding affinity, constraining resulting grains to sizes within the quantum confinement regime. The approach achieves high monodispersity (full-width at half-maximum = 23 nm with emission centred at 478 nm) united with strong coupling. We report as a result blue PeLEDs with an external quantum efficiency of 18% at 480 nm and 10% at 465 nm, to our knowledge the highest reported among perovskite blue LEDs by a factor of 1.5 and 2, respectively6,7.

Effect of Amino Acid Types on the Mechanical and Antimicrobial Properties of Amino Acid-Based Polyionic Liquid Hydrogels.

Polyionic liquid hydrogels attract increasing attention due to their unique properties and potential applications. However, research on amino acid-based polyionic liquid hydrogels is still in its infancy stage. Moreover, the effect of amino acid types on the properties of hydrogels is rarely studied to date. In this work, amino acid-based polyionic liquid hydrogels (D/L-PCAA hydrogels) are synthesized by copolymerizing vinyl choline-amino acid ionic liquids and acrylic acids using Al3+ as a crosslinking agent and bacterial cellulose (BC) as a reinforcing agent. The effects of amino acid types on mechanical and antimicrobial properties are systematically investigated. D-arginine-based hydrogel (D-PCArg) shows the highest tensile strength (220.7 KPa), D-phenylalanine-based hydrogel (D-PCPhe) exhibits the highest elongation at break (1346%), and L-aspartic acid-based hydrogel (L-PCAsp) has the highest elastic modulus (206.9 KPa) and toughness (1.74 MJ m-3). D/L-PCAsp hydrogels demonstrate stronger antibacterial capacity against Escherichia coli and Staphylococcus aureus, and D/L-PCPhe hydrogels possess higher antifungal activity against Cryptococcus neoformans. Moreover, the resultant hydrogels exhibit prominent hemocompatibility and low toxicity, as well as excellent self-healing capabilities (86%) and conductivity (2.8 S m-1). These results indicate that D/L-PCAA hydrogel provides a promise for applications in wound dressings.

ART altered DNA methylation of the imprinted gene H19 in fetal tissue after multifetal pregnancy reduction.

PURPOSE: This study aimed to assess whether assisted reproductive technology alters DNA methylation levels at the H19 promoter and H19 imprinting control element (ICE) in fetal tissues obtained after multifetal pregnancy reduction. METHODS: Fetal tissues from multiple pregnancies were obtained, including fresh and frozen-thawed embryos: nine from conventional in vitro fertilization (c-IVF), four from intracytoplasmic sperm injection (ICSI), ten from cryopreserved IVF embryos (cryo-IVF), and six from cryopreserved ICSI (cryo-ICSI) embryos. Next-generation sequencing-based bisulfite PCR was used to determine the DNA methylation status of three CpG islands (H19-1, H19-2, and H19-3) in the H19 promoter and H19 ICE. The primary outcome was H19-1 DNA methylation status, whereas secondary outcomes assessed H19-2, H19-3, and ICE methylation. RESULTS: The ICSI (ß = -3.189, 95% CI = -5.034 to -1.345, p = 0.0026), cryo-IVF (ß = -2.150, 95% CI = -3.706 to -0.593, p = 0.0129), and cryo-ICSI (ß = -2.238, 95% CI = -3.817 to -0.659, p = 0.0110) groups exhibited significantly lower methylation levels in the primary outcome H19-1 region than the c-IVF group after adjustment. For the secondary outcome H19-2 region, significant decreases were observed in the cryo-IVF (ß = -2.132, 95% CI = -4.071 to -0.192, p = 0.0425) and cryo-ICSI groups (ß = -2.598, 95% CI = -4.566 to -0.630, p = 0.0168). CONCLUSIONS: These findings further indicate that embryo cryopreservation and potentially ICSI can lower the methylation level of the H19 promoter, advocating for careful use of these techniques when necessary.

Interface Energy-Level Reorganization for Efficient Perovskite γ-Ray Detectors.

Metal halide perovskites are promising candidates for γ-ray spectrum detectors. However, achieving high-resolution energy spectra in single-photon pulse-height analysis mode remains challenging, due to the inevitable leakage currents degrade the recognizable fingerprint energies which is critical for resolving γ-ray spectroscopy. We demonstrate under high bias voltage, a deficient contact barrier can lead to excessive surface charge injection, thereby increasing leakage current from electrodes to perovskites. Hence, we conceive to employ surface ligand engineering on perovskite single crystals to manipulate energy levels to suppress leakage current. In particular, anchoring a strong dipole ligand onto the perovskite induced surface charge-density displacement, leading to a downward band bending and heightened the corresponding contact barrier. Consequently, the strategy minimized the detectors'leakage current by an order of magnitude, to as low as 44 nA cm-2. The resulting detectors show a significant improvement in energy resolution, 3.9% for 22Na 511 keV γ-rays has been achieved at room temperature. The resulting detector further resolves each fingerprint energy for 152Eu γ-spectrum, representing one of the best γ-rays perovskite detectors reported to date. Moreover, the detectors exhibited stabilized energy resolution without any degradation under a continuous electric field for over 300 minutes, representing the longest longevity reported to date.

Gut microbiota modification by diosgenin mediates antiepileptic effects in a mouse model of epilepsy.

Diosgenin, a natural steroid saponin, holds promise as a multitarget therapeutic for various diseases, including neurodegenerative conditions. Its efficacy in slowing Alzheimer's disease, Parkinson's disease, multiple sclerosis, and stroke progression has been demonstrated. However, the role of diosgenin in anti-epilepsy and its potential connection to the modulation of the intestinal microbiota remain poorly understood. In this study, exogenous diosgenin significantly mitigated pentylenetetrazole (PTZ)-induced seizures, learning and memory deficits, and hippocampal neuronal injury. 16S ribosomal RNA (16S rRNA) sequencing revealed a reversal in the decrease of Bacteroides and Parabacteroides genera in the PTZ-induced mouse epileptic model following diosgenin treatment. Fecal microbiota transplantation (FMT) experiments illustrated the involvement of diosgenin in modulating gut microbiota and providing neuroprotection against epilepsy. Our results further indicated the repression of enteric glial cells (EGCs) activation and the TLR4-MyD88 pathway, coupled with reduced production of inflammatory cytokines in the colonic lumen, and improved intestinal barrier function in epilepsy mice treated with diosgenin or FMT. This study suggests that diosgenin plays a role in modifying gut microbiota, contributing to the alleviation of intestinal inflammation and neuroinflammation, ultimately inhibiting epilepsy progression in a PTZ-induced mouse model. Diosgenin emerges as a potential therapeutic option for managing epilepsy and its associated comorbidities.

Clinical observation of menopause hormone therapy in postmenopausal women with euthyroid and mild subclinical hypothyroidism.

BACKGROUND: To evaluate the endocrine hormone and metabolic indices in postmenopausal women with euthyroid and mild subclinical hypothyroidism after menopause hormone therapy (MHT). METHODS: A retrospective study of 587 postmenopausal women receiving MHT was conducted. Median (25-75th percentile) age was 52 (49-54) years. According to thyroid stimulating hormone (TSH) levels at initial diagnosis, the patients were divided into three groups: I (euthyroid with low normal TSH range, n = 460), II (euthyroid with upper normal TSH range, n = 106) and III (mild subclinical hypothyroidism, n = 21). After a continuous oral MHT regimen using the same estradiol potency for 6-18 month cycles, serum endocrine hormone and metabolic indices were reassessed. RESULTS: Compared with baseline, serum TSH levels in groups I and II significantly changed but all values were within the normal range. No significant difference was observed in serum TSH levels in group III. After treatment, all serum free tri-iodothyronine and free thyroxine levels were within the normal range. Serum total cholesterol, triglyceride, fasting plasma glucose, fasting insulin levels and homeostasis model assessment of insulin resistance index had significantly decreased in group I. There were no significant differences in all observed lipid and glucose parameters in group III, before and after treatment. CONCLUSION: MHT did not affect thyroid function in postmenopausal women with euthyroid and mild subclinical hypothyroidism. MHT led to an improvement in lipid and glucose indicators in euthyroid women with low normal TSH range.

Manipulating Local Lattice Distortion for Spectrally Stable and Efficient Mixed-halide Blue Perovskite LEDs.

Mixed-halide perovskites are considered the most straightforward candidate to realize blue perovskite light-emitting diodes (PeLEDs). However, they suffer severe halide migration, leading to spectral instability, which is particularly exaggerated in high chloride alloying perovskites. Here, we demonstrate energy barrier of halide migration can be tuned by manipulating the degree of local lattice distortion (LLD). Enlarging the LLD degree to a suitable level can increase the halide migration energy barrier. We herein report an "A-site" cation engineering to tune the LLD degree to an optimal level. DFT simulation and experimental data confirm that LLD manipulation suppresses the halide migration in perovskites. Conclusively, mixed-halide blue PeLEDs with a champion EQE of 14.2 % at 475 nm have been achieved. Moreover, the devices exhibit excellent operational spectral stability (T50 of 72 min), representing one of the most efficient and stable pure-blue PeLEDs reported yet.

Turnip mosaic virus impairs perinuclear chloroplast clustering to facilitate viral infection.

Chloroplasts play crucial roles in plant defence against viral infection. We now report that chloroplast NADH dehydrogenase-like (NDH) complex M subunit gene (NdhM) was first up-regulated and then down-regulated in turnip mosaic virus (TuMV)-infected N. benthamiana. NbNdhM-silenced plants were more susceptible to TuMV, whereas overexpression of NbNdhM inhibited TuMV accumulation. Overexpression of NbNdhM significantly induced the clustering of chloroplasts around the nuclei and disturbing this clustering facilitated TuMV infection, suggesting that the clustering mediated by NbNdhM is a defence against TuMV. It was then shown that NbNdhM interacted with TuMV VPg, and that the NdhMs of different plant species interacted with the proteins of different viruses, implying that NdhM may be a common target of viruses. In the presence of TuMV VPg, NbNdhM, which is normally localized in the nucleus, chloroplasts, cell periphery and chloroplast stromules, colocalized with VPg at the nucleus and nucleolus, with significantly increased nuclear accumulation, while NbNdhM-mediated chloroplast clustering was significantly impaired. This study therefore indicates that NbNdhM has a defensive role in TuMV infection probably by inducing the perinuclear clustering of chloroplasts, and that the localization of NbNdhM is altered by its interaction with TuMV VPg in a way that promotes virus infection.

Effects of hormone replacement therapy on glucose and lipid metabolism in peri- and postmenopausal women with a history of menstrual disorders.

BACKGROUND: Previous studies have indicated that women with a history of menstrual disorders have an increased risk of metabolic and cardiovascular diseases. This has been attributed to the high proportion of polycystic ovary syndrome (PCOS) among this group. The favorable effects of hormone replacement therapy (HRT) on serum lipid profiles and glucose homeostasis in postmenopausal women is widely accepted. Whether HRT can also show positive effects on metabolic homeostasis in menopausal women with prior menstrual disorders (a putative PCOS phenotype) has not been reported yet. The aim of the study was to compare the effects of HRT on glucose and lipid metabolism in peri- and postmenopausal women with prior menstrual disorders and controls who did not have prior menstrual disorders. METHODS: A retrospective multicenter study was conducted including 595 peri- and postmenopausal women who received HRT at four hospitals in the Zhejiang Province from May 31, 2010 to March 8, 2021. Participants were divided into the Normal menstruation group and the Menstrual disorders group according to their prior usual menstrual cycle pattern. Glucose and lipid metabolism indicators were assessed at baseline and after HRT. The results were compared between and within the groups, and data from peri- and postmenopausal women were analyzed separately. RESULTS: HRT significantly decreased fasting insulin and homeostasis model assessment of insulin resistance in perimenopausal users, and fasting plasma glucose levels in postmenopausal users with prior menstrual disorders, compared with baseline. Furthermore, HRT decreased low-density lipoprotein cholesterol, total cholesterol, fasting insulin, fasting plasma glucose and homeostasis model assessment of insulin resistance in both peri- and postmenopausal controls, compared with baseline. Nevertheless, no significant differences were observed in any of the glucose or lipid metabolism indicators at baseline and follow-up, as well as changes from baseline levels between menopausal women with and without prior menstrual disorders. CONCLUSIONS: HRT shows more obvious within-group improvements in glucose and lipid metabolism in controls, but there is no significant between-group difference. Further prospective studies are required for confirmation.

Associations of age at natural menopause and occupations in Chinese female workers: A cross-sectional study.

AIMS: To investigate the impact of occupation types on age at natural menopause. METHODS: This is a nation-wide cross-sectional study based on 17,948 female workers aged over 40, who come from different industries or organizations. A face-to-face standardized questionnaire was conducted in all participants with the help of occupational hygienists. Occupational titles were coded according to the International Standard Classification of Occupations (2008) (ISCO08). Cox regression model was used to assess the association between each independent occupation and menopausal timing. Models were adjusted for marriage, education, average annual family income, parity, cigarette smoking, alcohol consumption. RESULTS: Higher risks of earlier age at natural menopause was found among legislators and senior officials (ISCO Minor group:111, HR = 2.328, P < 0.001), among other health associated professionals (ISCO Minor group: 325, HR = 1.477, P = 0.003), the workers involved in mining and mineral processing (ISCO Minor group: 811, HR = 1.515, P = 0.048) and metal processing and finishing (ISCO Minor group: 812, HR = 1.722, P < 0.001). Reduced risks of earlier age at natural menopause, including: finance professionals (ISCO Minor group: 241, HR = 0.751, P = 0.021), manufacturing and construction supervisors (ISCO Minor group: 312, HR = 0.477, P = 0.002), administrative and specialized secretaries (ISCO Minor group: 334, HR = 0.788, P = 0.045), cleaners and helpers (ISCO Minor group: 911, HR = 0.633, P = 0.01). CONCLUSIONS: This is the first study to address the influence of occupation types on reproductive aging, showing some specific occupations could be associated with age at natural menopause. Further investigations are necessary to clarify whether it is chance finding or a true association.

Relationship between thyroid disorders and uterine fibroids among reproductive-age women.

Uterine fibroids and thyroid nodules, both of which are crucially affected by estrogen, are common diseases among reproductive-age women. However, little attention has been paid to the association between the two diseases. This retrospective case-control study aimed to assess the relationships among thyroid nodules, thyroid function and uterine fibroids in China. We reviewed the electronic records of 853 reproductive-age women who attended health check-ups at the Second Affiliated Hospital of Wenzhou Medical University from July 1st, 2017, to June 30th, 2018. All subjects received transvaginal pelvic ultrasound, thyroid ultrasound, thyroid function, and other laboratory tests. We found that the prevalence of thyroid nodules in subjects with uterine fibroids was remarkably higher than that in subjects without fibroids. The proportion of thyroid nodules ≥1 cm in subjects with uterine fibroids was significantly higher than that in subjects without fibroids. Women with thyroid nodules had a higher proportion of multiple uterine fibroids than women without thyroid nodules. Among the parameters of thyroid function, the only statistically significant parameter was total triiodothyronine, i.e., women with uterine fibroids had lower total triiodothyronine levels than unaffected controls; however, the total triiodothyronine levels were within the normal ranges. Moreover, no significant difference was noted in thyroid hormone status between subjects with and without uterine fibroids. Our findings suggest that thyroid nodules are positively correlated with uterine fibroids among reproductive-age women in China. Further studies are needed to confirm this association and fully understand the common pathogenetic mechanism underlying the association between uterine fibroids and thyroid nodules.

The hypersensitive induced reaction 3 (HIR3) gene contributes to plant basal resistance via an EDS1 and salicylic acid-dependent pathway.

The hypersensitive-induced reaction (HIR) gene family is associated with the hypersensitive response (HR) that is a part of the plant defense system against bacterial and fungal pathogens. The involvement of HIR genes in response to viral pathogens has not yet been studied. We now report that the HIR3 genes of Nicotiana benthamiana and Oryza sativa (rice) were upregulated following rice stripe virus (RSV) infection. Silencing of HIR3s in N. benthamiana resulted in an increased accumulation of RSV RNAs, whereas overexpression of HIR3s in N. benthamiana or rice reduced the expression of RSV RNAs and decreased symptom severity, while also conferring resistance to Turnip mosaic virus, Potato virus X, and the bacterial pathogens Pseudomonas syringae and Xanthomonas oryzae. Silencing of HIR3 genes in N. benthamiana reduced the content of salicylic acid (SA) and was accompanied by the downregulated expression of genes in the SA pathway. Transient expression of the two HIR3 gene homologs from N. benthamiana or the rice HIR3 gene in N. benthamiana leaves caused cell death and an accumulation of SA, but did not do so in EDS1-silenced plants or in plants expressing NahG. The results indicate that HIR3 contributes to plant basal resistance via an EDS1- and SA-dependent pathway.

The role of atorvastatin in suppressing tumor growth of uterine fibroids.

BACKGROUND: Medical therapeutic options remain quite limited for uterine fibroids treatment. Statins, competitive inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, have anti-tumoral effects on multiple cancer types, however, little is known about their effects on uterine fibroids. METHODS: Initially, we conducted a retrospective study of 120 patients with uterine fibroids and hyperlipidemia from the Second Affiliated Hospital of Wenzhou Medical University. Then, we evaluated the effect of atorvastatin on proliferation and apoptosis both in immortalized uterine fibroids cells and primary uterine fibroids cells. Furthermore, the molecular mechanism by which atorvastatin suppressed uterine fibroids cell growth was explored. RESULTS: Our results showed that atorvastatin use for 1 or 2 years significantly suppressed growth of uterine fibroids. Atorvastatin inhibited the proliferation of immortalized and primary uterine fibroids cells in a dose and time-dependent manner and stimulated apoptosis of uterine fibroids cells by inducing caspase-3 activation, up-regulating Bim and down-regulating Bcl-2. Additionally, atorvastatin treatment suppressed phosphorylation of ERK1/2 and JNK. Furthermore, GGPP, a downstream lipid isoprenoid intermediate, significantly rescued the effect of atorvastatin. CONCLUSIONS: These results suggest that atorvastatin exerts anti-tumoral effects on uterine fibroids through inhibition of cell proliferation and induction of apoptosis in HMG-CoA-dependent pathway. Our results provide the first clinical and preclinical data on the use of atorvastatin as a promising nonsurgical treatment option for uterine fibroids.

Prognostic values of DNA mismatch repair genes in ovarian cancer patients treated with platinum-based chemotherapy.

PURPOSE: DNA mismatch repair (MMR) is a highly conserved biological pathway that plays a key role in maintaining genomic stability. MMR has been reported as a prognostic marker in certain cancers; however, the results are controversial. Therefore, identification of the prognostic value of MMR genes in ovarian cancer based on a large sample size is pivotal. METHODS: In the current study, we systemically investigated the prognostic roles of seven MMR genes, MSH2, MSH3, MSH6, MLH1, MLH3, PMS1 and PMS2, in ovarian cancer patients treated with platinum-based chemotherapy through "The Kaplan-Meier plotter" (KM plotter) database, which contains gene expression data and survival information of ovarian cancer patients. RESULTS: Among seven MMR genes, high mRNA levels of MSH6, MLH1 and PMS2 were significantly associated with a better overall survival for all ovarian cancer patients treated with platinum-based chemotherapy, especially in late-stage and poor-differentiated ovarian cancer patients. Increased MSH6 and PMS2 mRNA expression was correlated with a favorable overall survival in serous ovarian cancer patients. CONCLUSIONS: Our results indicate that sufficient MMR system is associated with an improved survival in ovarian cancer treated with platinum-based chemotherapy. MMR gene may be a potential prognosis predictor in ovarian cancer.

The ubiquitin-proteasome system in the tumor immune microenvironment: a key force in combination therapy.

The ubiquitin-proteasome system (UPS) plays a crucial role in modulating the proliferation, activation, and normal functioning of immune cells through the regulation of protein degradation and function. By influencing the expression of immune checkpoint-associated proteins, the UPS modulates T cell-mediated anti-tumor immune responses and can potentially facilitate the immune escape of tumor cells. Additionally, the UPS contributes to the remodeling of the tumor immunosuppressive microenvironment (TIME) by regulating B cells, dendritic cells (DCs), macrophages, and Treg cells. Targeting the UPS in conjunction with immune checkpoint-associated proteins, and combining these with other therapeutic approaches, may significantly enhance the efficacy of combination therapies and pave the way for novel cancer treatment strategies. In this review, we first summarize the composition and alterations of the TIME, with a particular emphasis on the role of the UPS in TIME and its interactions with various immune cell types. Finally, we explore the potential of combining UPS-targeted therapies with immunotherapy to substantially improve the effectiveness of immunotherapy and enhance patient survival outcomes.

Autophagy and Apoptosis in Rabies Virus Replication.

Rabies virus (RABV) is a single-stranded negative-sense RNA virus belonging to the Rhabdoviridae family and Lyssavirus genus, which is highly neurotropic and can infect almost all warm-blooded animals, including humans. Autophagy and apoptosis are two evolutionarily conserved and genetically regulated processes that maintain cellular and organismal homeostasis, respectively. Autophagy recycles unnecessary or dysfunctional intracellular organelles and molecules in a cell, whereas apoptosis eliminates damaged or unwanted cells in an organism. Studies have shown that RABV can induce both autophagy and apoptosis in target cells. To advance our understanding of pathogenesis of rabies, this paper reviews the molecular mechanisms of autophagy and apoptosis induced by RABV and the effects of the two cellular events on RABV replication.

Recent Advances in Natural-Polymer-Based Hydrogels for Body Movement and Biomedical Monitoring.

In recent years, the interest in medical monitoring for human health has been rapidly increasing due to widespread concern. Hydrogels are widely used in medical monitoring and other fields due to their excellent mechanical properties, electrical conductivity and adhesion. However, some of the non-degradable materials in hydrogels may cause some environmental damage and resource waste. Therefore, organic renewable natural polymers with excellent properties of biocompatibility, biodegradability, low cost and non-toxicity are expected to serve as an alternative to those non-degradable materials, and also provide a broad application prospect for the development of natural-polymer-based hydrogels as flexible electronic devices. This paper reviews the progress of research on many different types of natural-polymer-based hydrogels such as proteins and polysaccharides. The applications of natural-polymer-based hydrogels in body movement detection and biomedical monitoring are then discussed. Finally, the present challenges and future prospects of natural polymer-based hydrogels are summarized.

Melatonin delayed senescence by modulating the contents of plant signalling molecules in postharvest okras.

Okra has been widely cultivated worldwide. Consumers appreciate its nutritional value and delicious taste. However, okra is very perishable after harvest because of rapid senescence and high susceptibility to mechanical injuries, which limits its storage life and reduces consumer acceptance. This study examined the influence of melatonin treatment on senescence process and endogenous plant signalling molecules in postharvest okras. The results indicated that melatonin treatment delayed senescence by increasing the endogenous melatonin content through upregulation of its biosynthetic genes. In addition, the treatment increased the contents of indole-3-acetic acid (IAA) and gibberellin (GA) due to the positive modulation of their metabolic and signalling genes. Furthermore, treated okras exhibited higher levels of γ-aminobutyric acid (GABA) but lower abscisic acid (ABA) content, contributing to the delayed senescence process compared to control. Overall, the findings suggested that melatonin postponed senescence in okras fruit by positively regulating endogenous signalling molecules such as melatonin, IAA, GABA, GA, and ABA.