Normal weight obesity is associated with lower AFC and adverse IVF outcomes

BackgroundBody weight could be classified into underweight, normal weight and overweight according to percentage of body fat (%BF), and normal weight obesity (NWO) is defined as a normal BMI but a high %BF. While the impact of NWO in women fecundity remain unknow. Therefore, this study aimed to investigate the associations between %BF and reproductive outcomes among in vitro fertilization (IVF) women with normal BMI.MethodsA total of 469 women were included in this study and were classified into low %BF, normal %BF and high %BF according to previous study. Multivariate generalized regression models were employed to evaluate the associations of %BF with ovarian reserve parameters, IVF outcomes and early pregnancy outcomes. We further run sensitivity analyses by restricted the analysis to young women and those only with tubal factor, respectively.ResultsAbout 32.2% of normal BMI women were misclassified according %BF, with 16.4% of them were low %BF and 15.8% were high %BF. The high %BF group had significantly lower antral follicle count (AFC) than normal %BF groups, and the AFC showed a tendency of decrease as %BF increased. In sensitivity analysis in young women, high %BF group also had significantly lower number of good-quality embryos when compared to normal %BF groups. The results expanded to all IVF outcomes when analysis restricted to tubal factor women.ConclusionIn summary, misclassifications of body weight status based on BMI are common according to %BF, and NWO is associated with adverse reproductive outcomes

Low body mass index adversely affects the live birth rate following fresh embryo transfer in Chinese women with polycystic ovary syndrome: a pilot study

ObjectiveTo examine the relationship between body mass index (BMI) and pregnancy outcomes after fresh embryo transfer in patients with polycystic ovary syndrome (PCOS).MethodsWomen diagnosed with PCOS who underwent in vitro fertilization or intracytoplasmic sperm injection treatment at the Reproductive Center of Guangdong Maternal and Child Health Hospital in China between August 2014 and July 2023 were included. Patients were divided into four groups based on BMI: Low <18.5Kg/m2 (group 1); Normal 18.5≤BMI <24 Kg/m2(group 2); Overweight 24≤BMI <28 Kg/m2(group 3); Obesity ≥28 Kg/m2(group 4). The retrospective cohort study explored the relationship between BMI and pregnancy outcomes using a logistic regression approach. The live birth rates of different BMI groups were compared after adjusting for age, antimullerian hormone (AMH), antral follicle count (AFC), homeostatic model assessment of insulin resistance (HOMA), estrogen (E2), total testosterone (T), baseline follicle-stimulating hormone (bFSH), and baseline luteinizing hormone (bLH).ResultsA total of 649 patients with PCOS who underwent fresh embryo transfer were included. A curvilinear relationship was observed between BMI and pregnancy outcomes. Compared with the normal BMI group, the low BMI group had the lowest live birth rate (P = 0.021). An inflection point was identified at approximately 22 kg/m². When BMI was below 22 kg/m², the live birth rate increased by 29% for each 1 kg/m² increase in BMI (P = 0.018). When BMI exceeded 22 kg/m², the live birth rate plateaued. A significant interaction between age and BMI was also observed in relation to live birth rate (P = 0.011), with the adverse effect of low BMI being particularly pronounced in younger patients.ConclusionAmong patients with PCOS, those with low BMI had the lowest live birth rate following fresh embryo transfer. The optimal BMI associated with the highest live birth rate was approximately 22 kg/m²

Transcriptomic profiling reveals RetS-mediated regulation of type VI secretion system and host cell responses in Pseudomonas aeruginosa infections

Pseudomonas aeruginosa is a major opportunistic pathogen that causes chronic infections, particularly in patients with cystic fibrosis and chronic obstructive pulmonary disease (COPD). The type VI secretion system (T6SS) is a primary virulence factor of P. aeruginosa in chronic infections. The objective of this study was to elucidate the regulatory mechanisms and pathogenic effects of the T6SS during P. aeruginosa infection, utilizing transcriptome sequencing and functional assays. We found that T6SS expression is elevated in P. aeruginosa isolated from chronically infected patients. Deletion of the retS gene activates P. aeruginosa PAO1 T6SS while repressing T3SS in vitro. Bacterial and cellular transcriptome sequencing analyses showed that T6SS genes were upregulated, while T3SS genes were downregulated in the ΔretS mutant. Additionally, the expression levels of the fimbriae gene cupC, the histidine phosphotransfer protein hptC (PA0033), and the transcription factor PA0034 were significantly increased. Subsequent experiments revealed that adhesion mediated by cupC enhances the contact-killing activity of the T6SS. Deletion of the hptC-PA0034 operon results in the down-regulation of cupC expression. The ΔretSΔcupC and ΔretSΔhptC-PA0034 mutants exhibited reduced cytotoxicity compared to the ΔretS mutant, similar to the ΔretSΔclpV1ΔclpV2 mutant. The ΔretS infection increased cell death, inflammatory factors (IL-1β, IL-6, TNF-α), and reactive oxygen species compared to a T6SS-inactive strain. Importantly, our study demonstrates that the T6SS activates the PDE4C pathway in epithelial cells, leading to significant cellular alterations. The application of PDE inhibitors effectively mitigates cell damage and inflammatory responses. These findings highlight the critical role of T6SS in modulating host cell signaling and suggest potential therapeutic strategies for conditions associated with T6SS-mediated inflammation

Improving Signalling Performance of Proactive MANET Routing Protocols

I, [Yangcheng Huang], confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. 2 Abstract 3 A mobile ad hoc network (MANET) comprises a set of nodes connected by radio wireless links in a temporary manner. The topology of a MANET may change rapidly and unpredictably because of node mobility. Resources in such networks (such as bandwidth and battery life) are constrained. These issues make routing packets between any node pair a challenging task, especially for proactive MANET routing protocols. Each node of a proactive MANET routing protocol maintains routing information to every other node in the network at all times. The routing information has to be updated to reflect the topology changes and guarantee the correctness of route selection. Additionally, the dissemination of control messages has to be optimised for efficient resource usage and to alleviate channel contention problems. This dissertation investigates the signalling performance of proactive MANET routing protocols, using a combination of simulation-based study and model-based analysis. The impacts of soft state signalling, especially the refresh intervals, are studied under various scenarios. A variety of topology advertisement strategies are presented. Two optimised neighbour detection schemes are proposed, namely the Dynamic Timer algorithm and the Fast Neighbour Handshake algorithm, in order to enhance routing performance. These efforts have allowed this dissertation to provide a clear insight into various aspects of softstate signalling performance in dynamic resource-constrained networks, and to provide useful understanding on how to effectively design MANET protocols. In addition, this research proposes a number of original signalling mechanisms to improve routing performance. These are described and evaluated within the dissertation along with recommendations for further study