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Cisplatin (DDP) resistance in advanced stages of ovarian cancer significantly reduces survival rates. Mitochondria may serve as a potential therapeutic target for ovarian cancer. Pal-pHK-pKV is a mitochondrial targeting peptide synthesized by supramolecular assembly. Our study aims to investigate whether Pal-pHK-pKV serves as a useful strategy to reverse DDP resistance in ovarian cancer. Subcutaneous tumor implantation of the DDP-resistant ovarian cancer cell line A2780CP was conducted in nude mice, and drugs were administered intraperitoneally to compare the inhibitory effects of Pal-pHK-pKV and DDP on A2780CP cells in vivo. Combination index values were calculated for various concentrations of DDP and Pal-pHK-pKV to determine the optimal combination concentration. Mitochondrial membrane potential, cytochrome C distribution and immunofluorescence were also measured. Our studies demonstrated that Pal-pHK-pKV treatment reduced the proliferation, invasion and metastasis of ovarian cancer cells and impaired mitochondrial function. Furthermore, the combination of Pal-pHK-pKV and DDP exhibited a synergistic effect. Mechanistically, Pal-pHK-pKV can impair mitochondrial function, reduce mitochondrial membrane potential and release ROS. On the other hand, Pal-pHK-pKV can affect ERK pathway activation and inhibit tumor development. In conclusion, the mitochondria-specific amphiphilic peptide Pal-pHK-pKV provides a novel approach for treating ovarian cancer and may potentially overcome DDP drug resistance.

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BACKGROUND: Peer assisted learning (PAL), where student leaders facilitate their peers' learning, is prevalent in higher education. However, PAL leaders' development in physiotherapy education and their role perceptions relating to their future professional practice are understudied. PURPOSE: We aimed to understand how PAL leaders in physiotherapy education perceive their own academic learning and personal development, and how they view their experiences as PAL leaders in relation to future physiotherapy practice. METHODS: Focus group interviews were used to collect qualitative data from third-semester students who had been PAL leaders (n = 19). Data were analyzed using a reflexive, thematic analysis. RESULTS: Three main themes were generated: "Being a PAL leader consolidates knowledge and facilitates new learning," "Personal growth through experiential learning outside the comfort zone within a community of practice," and "Learning by leading - transferability of being a PAL leader to future physiotherapy practice." CONCLUSION: Overall, physiotherapy students leading PAL study groups demonstrated academic, personal, and professional growth via experiential learning in a community of practice. They developed skills likely transferable into their future physiotherapy roles. Our findings propose PAL study groups as an arena for PAL leaders to practice complex physiotherapy competences, positioning PAL study groups as valuable preclinical practice for physiotherapy students.

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Phenylalanine ammonia lyase (PAL) is a widely studied enzyme in plant biology due to its role in connecting primary metabolism to secondary phenylpropanoid metabolism, significantly influencing plant growth, development, and stress response. Although PAL genes have been extensively studied in various plant species but their exploration in cucumber has been limited. This study successfully identified 11 CsPAL genes in Cucumis sativus (cucumber). These CsPAL genes were categorized based on their conserved sequences revealing patterns through MEME analysis and multiple sequence alignment. Interestingly, cis-elements related to stress were found in the promoter regions of CsPAL genes, indicating their involvement in responding to abiotic stress. Furthermore, these gene's promoters contained components associated with light, development and hormone responsiveness. This suggests that they may have roles in hormone developmental processes. MicroRNAs were identified as a key regulators for the CsPAL genes, playing a crucial role in modulating their expression. This discovery underscores the complex regulatory network involved in the plant's response to various stress conditions. The influence of these microRNAs further highlights the complicated mechanisms that plants use to manage stress. Gene expression patterns were analyzed using RNA-seq data. The significant upregulation of CsPAL9 during HT3h (heat stress for 3 h) and the heightened upregulation of both CsPAL9 and CsPAL7 under HT6h (heat stress for 6 h) in the transcriptome study suggest a potential role for these genes in cucumber's tolerance to heat stress. This comprehensive investigation aims to enhance our understanding of the PAL gene family's versatility, offering valuable insights for advancements in cucumber genetics.

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Bovine viral diarrhea (BVD) is a single-stranded, positive-sense ribonucleic acid (RNA) virus belonging to the genus Pestivirus of the Flaviviridae family. BVD frequently causes economic losses to farmers. Among bovine viral diarrhea virus (BVDV) strains, BVDV-1b is predominant and widespread in Hanwoo calves. Reverse-transcription polymerase chain reaction (RT-PCR) is an essential method for diagnosing BVDV-1b and has become the gold standard for diagnosis in the Republic of Korea. However, this diagnostic method is time-consuming and requires expensive equipment. Therefore, Clustered regularly interspaced short palindromic repeats-Cas (CRISPR-Cas) systems have been used for point-of-care (POC) testing of viruses. Developing a sensitive and specific method for POC testing of BVDV-1b would be advantageous for controlling the spread of infection. Thus, this study aimed to develop a novel nucleic acid detection method using the CRISPR-Cas13 system for POC testing of BVDV-1b. The sequence of the BVD virus was extracted from National Center for Biotechnology Information (NC_001461.1), and the 5' untranslated region, commonly used for detection, was selected. CRISPR RNA (crRNA) was designed using the Cas13 design program and optimized for the expression and purification of the LwCas13a protein. Madin Darby bovine kidney (MDBK) cells were infected with BVDV-1b, incubated, and the viral RNA was extracted. To enable POC viral detection, the compatibility of the CRISPR-Cas13 system was verified with a paper-based strip through collateral cleavage activity. Finally, a colorimetric assay was used to evaluate the detection of BVDV-1b by combining the previously obtained crRNA and Cas13a protein on a paper strip. In conclusion, the CRISPR-Cas13 system is highly sensitive, specific, and capable of nucleic acid detection, making it an optimal system for the early point-of-care testing of BVDV-1b.

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Binary AsxSe100-x alloys from the border of a glass-forming region (65 < x < 70) subjected to nanomilling in dry and dry-wet modes are characterized by the XRPD, micro-Raman scattering (micro-RS) and revised positron annihilation lifetime (PAL) methods complemented by a disproportionality analysis using the quantum-chemical cluster modeling approach. These alloys are examined with respect to tetra-arsenic biselenide As4Se2 stoichiometry, realized in glassy g-As65Se35, glassy-crystalline g/c-As67Se33 and glassy-crystalline g/c-As70Se30. From the XRPD results, the number of rhombohedral As and cubic arsenolite As2O3 phases in As-Se alloys increases after nanomilling, especially in the wet mode realized in a PVP water solution. Nanomilling-driven amorphization and reamorphization transformations in these alloys are identified by an analysis of diffuse peak halos in their XRPD patterning, showing the interplay between the levels of a medium-range structure (disruption of the intermediate-range ordering at the cost of an extended-range one). From the micro-RS spectroscopy results, these alloys are stabilized by molecular thioarsenides As4Sen (n = 3, 4), regardless of their phase composition, remnants of thioarsenide molecules destructed under nanomilling being reincorporated into a glass network undergoing a polyamorphic transition. From the PAL spectroscopy results, volumetric changes in the wet-milled alloys with respect to the dry-milled ones are identified as resulting from a direct conversion of the bound positron-electron (Ps, positronium) states in the positron traps. Ps-hosting holes in the PVP medium appear instead of positron traps, with ~0.36-0.38 ns lifetimes ascribed to multivacancies in the As-Se matrix. The superposition of PAL spectrum peaks and tails for pelletized PVP, unmilled, dry-milled, and dry-wet-milled As-Se samples shows a spectacular smoothly decaying trend. The microstructure scenarios of the spontaneous (under quenching) and activated (under nanomilling) decomposition of principal network clusters in As4Se2-bearing arsenoselenides are recognized. Over-constrained As6·(2/3) ring-like network clusters acting as pre-cursors of the rhombohedral As phase are the main products of this decomposition. Two spontaneous processes for creating thioarsenides with crystalline counterparts explain the location of the glass-forming border in an As-Se system near the As4Se2 composition, while an activated decomposition process for creating layered As2Se3 structures is responsible for the nanomilling-driven molecular-to-network transition.

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Phenylpropanoids, a class of specialized metabolites, play crucial roles in plant growth and stress adaptation and include diverse phenolic compounds such as flavonoids. Phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS) are essential enzymes functioning at the entry points of general phenylpropanoid biosynthesis and flavonoid biosynthesis, respectively. In Arabidopsis, PAL and CHS are turned over through ubiquitination-dependent proteasomal degradation. Specific kelch domain-containing F-Box (KFB) proteins as components of ubiquitin E3 ligase directly interact with PAL or CHS, leading to polyubiquitinated PAL and CHS, which in turn influences phenylpropanoid and flavonoid production. Although phenylpropanoids are vital for tomato nutritional value and stress responses, the post-translational regulation of PAL and CHS in tomato remains unknown. We identified 31 putative KFB-encoding genes in the tomato genome. Our homology analysis and phylogenetic study predicted four PAL-interacting SlKFBs, while SlKFB18 was identified as the sole candidate for the CHS-interacting KFB. Consistent with their homolog function, the predicted four PAL-interacting SlKFBs function in PAL degradation. Surprisingly, SlKFB18 did not interact with tomato CHS and the overexpression or knocking out of SlKFB18 did not affect phenylpropanoid contents in tomato transgenic lines, suggesting its irreverence with flavonoid metabolism. Our study successfully discovered the post-translational regulatory machinery of PALs in tomato while highlighting the limitation of relying solely on a homology-based approach to predict interacting partners of F-box proteins.

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The conquest of land posed severe problems to plants which they had to cope with by adapting biosynthetic capacities. Adaptations to respond to UV irradiation, water loss, pathogen and herbivore defense, and the earth's pull were essential. Chemical compounds alleviating these problems can be synthesized by the phenylpropanoid pathway, the core of which are three enzymes: phenylalanine ammonia-lyase (PAL), cinnamic acid 4-hydroxylase, and 4-coumaric acid coenzyme A-ligase (4CL). The genomes of model organisms, Chara braunii as aquatic alga and the two bryophytes Physcomitrium patens and Marchantia polymorpha, were searched for sequences encoding PAL and 4CL and selected sequences heterologously expressed in Escherichia coli for biochemical characterization. Several possible isoforms were identified for both enzymes in Marchantia polymorpha and Physcomitrium patens, while only one or two isoforms could be retrieved for Chara braunii. Active forms of both enzymes were found in all three organisms, although the catalytic efficiencies varied in a wide range. l-Phenylalanine was accepted as best substrate by all PAL-like enzymes, despite annotations in some cases suggesting different activities. The substrate spectrum of 4CLs was more diverse, but caffeic and/or 4-coumaric acids generally were the best-accepted substrates. Our investigations show that PAL and 4CL, important enzymes for the formation of phenolic compounds, are present and active in extant charophytes and bryophytes as model organisms for the conquest of land.

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In this research, qualitative characteristics were studied under different post-harvest treatments in Hass and Fuerte cultivars of avocado (Persea americana) fruits. The post-harvest treatments performed in fruits of these cultivars comprised Ethrel application and plastic film (membrane) covering. The measurements of qualitative characteristics were related to color; flesh consistency; measurements of titratable acidity, total soluble solids, percentage of total phenolic contents, and ascorbic peroxidase activity; and the real-time (quantitative) polymerase chain reaction (qPCR) of gene expression and enzyme activities of phenylalanine ammonia-lyase (PAL) and beta-galactosidase (ß-gal). The experiments found that the application of plastic film has excellent results in retaining qualitative characteristics and enzyme activities via maintaining firmness in higher levels. The plastic film covering appeared to delay ripening without the use of chemicals and, therefore, it has the potential to extend the duration of the post-harvest life of the avocado fruit. Variations between the two cultivars were found in the measurements of total soluble solids (Fuerte cultivar showed an increase of 22%, whereas Hass cultivar showed an increase of 120% in Brix values) and total phenolic contents (Fuerte cultivar showed a decrease of 16% and Hass cultivar showed an increase of 29%). It is worth noting that PAL's activity increased significantly (over 44%), as compared to other treatments, and ß-galactosidase's activity decreased, as compared to other treatments. In conclusion, plastic film covering results in a decrease in the activity of ß-galactosidase, as shown by the reaction of hydrolysis (enzyme activity) but also from the expression of the related genes.

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Background and Objective: Persistent air leak (PAL) represents a challenging medical condition characterized by prolonged air leak from the lung parenchyma into the pleural cavity, often associated with alveolar-pleural fistula or bronchopleural fistula (BPF). The objective of this narrative review is to explore the causes, clinical implications, and the evolving landscape of bronchoscopic treatment options for PAL. Methods: The literature search for this review was conducted using databases such as PubMed/MEDLINE, and Scopus databases. Articles published from inception until 28th August, 2023, focusing on studies that discussed the causes, diagnosis, and management strategies for PAL were included. Keywords included bronchoscopic management, bronchopleural fistula, endobronchial valve, sealant, blood patch pleurodesis, spigot, air leak, PAL, management, comparative study. Key Content and Findings: PAL commonly arises from secondary spontaneous pneumothorax, necrotizing pneumonia, barotrauma induced by mechanical ventilation, chest trauma, or postoperative complications. Understanding the underlying etiology is crucial for tailoring effective management strategies. While conventional intercostal drainage resolves the majority of pneumothorax cases, PAL is diagnosed when the air leak persists beyond 5 to 7 days. Prolonged PAL can lead to worsening pneumothorax, respiratory distress, and increased morbidity. Early identification and intervention are essential to prevent complications. Conservative approaches involve close monitoring and supplemental oxygen therapy. These strategies aim to promote natural healing and resolution of the air leak without invasive interventions. Bronchoscopic techniques, such as endobronchial valves (EBVs), sealants, and autologous blood patch (ABP), have emerged as promising alternatives for refractory PAL. These interventions offer a targeted and minimally invasive approach to seal the fistulous connection, promoting faster recovery and reducing the need for surgical interventions. Conclusions: PAL is a clinical challenge, and their management requires a tailored approach based on the underlying cause and severity. Bronchoscopic interventions have shown efficacy in cases of refractory PAL. Early recognition, multidisciplinary collaboration, and a personalized treatment plan are essential for optimizing outcomes in patients with PAL.

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This study systematically investigated the physiological and molecular responses of the wheat mutant 'XC-MU201' under high-temperature stress through comprehensive transcriptome analysis and physiological measurements. RNA sequencing of 21 samples across seven different treatment groups revealed, through Weighted Gene Co-expression Network Analysis (WGCNA), 13 modules among 9071 genes closely related to high-temperature treatments. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed significant enrichment of lignin biosynthesis-related modules under high-temperature conditions, especially at the H-10DAT, H-20DAT, and H-30DAT time points. Experimental results demonstrated a significant increase in lignin content in high-temperature-treated samples, confirmed by tissue staining methods, indicating wheat's adaptation to heat damage through lignin accumulation. The phenylalanine ammonia-lyase gene (TaPAL33) was significantly upregulated under high-temperature stress, peaking at H-30DAT, suggesting its critical role in cellular defense mechanisms. Overexpression of TaPAL33 in the wheat variety 'Xinchun 11' enhanced lignin synthesis but inhibited growth. Subcellular localization of GFP-labeled TaPAL33 in tobacco cells showed its distribution mainly in the cytoplasm and cell membrane. Transgenic wheat exhibited higher PAL enzyme activity, enhanced antioxidant defense, and reduced oxidative damage under high-temperature stress, outperforming wild-type wheat. These results highlight TaPAL33's key role in improving wheat heat tolerance and provide a genetic foundation for future research and applications.

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Despite the great progress in developing wound dressings, delayed wound closure still remains a global challenge. Thus, developing novel wound dressings and employing advanced strategies, including tissue engineering, are urgently desired. The carboxylated cellulose was developed through the in situ synthesis method and further reinforced by incorporating pal-KTTKS to stimulate collagen synthesis and improve wound healing. The developed composites supported cell adhesion and proliferation and showed good biocompatibility. To boost wound-healing performance, adipose-derived mesenchymal stem cells (MSC) were seeded on the pal-KTTKS-enriched composites to be implanted in a rat model of burn wound healing. Healthy male rats were randomly divided into four groups and wound-healing performance of Vaseline gauze (control), carboxylated cellulose (CBC), pal-KTTKS-enriched CBC (KTTKS-CBC), and MSCs seeded on the KTTKS-CBC composites (MSC-KTTKS-CBC) were evaluated on days 3, 7, and 14 post-implantation. In each group, the designed therapeutic dressings were renewed every 5 days to increase wound-healing performance. We found that KTTKS-CBC and MSC-KTTKS-CBC composites exhibited significantly better wound healing capability, as evidenced by significantly alleviated inflammation, increased collagen deposition, improved angiogenesis, and considerably accelerated wound closure. Nevertheless, the best wound-healing performance was observed in the MSC-KTTKS-CBC groups among all four groups. This research suggests that the MSC-KTTKS-CBC composite offers a great deal of promise as a wound dressing to enhance wound regeneration and expedite wound closure in the clinic.

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Background: Even though innumerable quality of life (QOL) questionnaires have been developed in palliative care, there is no gold standard assessment tool for QOL and no single questionnaire that fits all purposes and individuals. An important challenge to QOL assessments in palliative care is the highly diverse patient population with different diagnoses, disease states/prognosis, and languages. In an outpatient palliative care clinic population, FACIT-Pal-14 proved to be a valid and reliable scale in palliative care patients. Objectives: We aimed to (i) determine the psychometric properties of the Tagalog version of the Functional Assessment of Chronic Illness Therapy - Palliative Care - 14 (FACIT-Pal-14) and (ii) measure the Quality of Life (QOL) of Filipino cancer patients. Methods: This was a cross-sectional study. License for the use of the Tagalog version 4 of the FACIT-Pal-14 was requested from FACIT.org. To know the psychometric properties of the scales, Cronbach's alpha coefficient was used to assess reliability, and exploratory factor analysis, Pearson correlations, and independent samples T-test were used to determine validity. Results: The Tagalog FACIT-Pal-14 was administered to 500 Filipino cancer patients consulting at the outpatient department of a training and regional medical center. The participants were mostly female (65.5%), aged 64 years and younger (82.6%), and had breast cancer (53.2%), colorectal cancer (19.2%), and lung cancer (9.4%). The mean Tagalog FACIT-Pal-14 score was 47.35 out of 56 (SD=7.14). The Cronbach's alpha coefficient of the Tagalog version of FACIT-Pal-14 was 0.784. Significantly lower mean Tagalog FACIT-Pal-14 scores were found in patients with Karnofsky Performance Status (KPS) 70 and lower, and Eastern Cooperative Oncology Group Performance Status (ECOG-PS) 2 and above compared with patients with KPS 80 and higher and ECOG-PS 0-1. (t=3.439, p<.001). While the Tagalog FACIT-Pal-14 scores, KPS, and ECOG scores only revealed a very weak, positive correlation (r=0.095; p <0.05), this ability to distinguish between groups known to differ regarding performance status showed the construct validity of the Tagalog FACIT-Pal-14. Conclusions: In an outpatient oncology clinic population, the FACIT-Pal 14 showed evidence of reliability and construct validity for evaluating palliative care-specific QOL in Filipino cancer patients. Using this measure, Filipino cancer patients have a good QOL. Therefore, it is recommended that the Tagalog FACIT-Pal-14 be used on subsequent patient follow-ups to assess how their QOL would change over time so that the palliative care services provided will be suited to their needs.

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BACKGROUND: The liver function reserve has a significant impact on the therapeutic effects of anti-programmed cell death-1 (PD-1) for hepatocellular carcinoma (HCC). This study aimed to comprehensively evaluate the ability of liver-function-based indicators to predict prognosis and construct a novel prognostic score for HCC patients with anti-PD-1 immunotherapy. METHODS: Between July 2018 and January 2020, patients diagnosed with HCC who received anti-PD-1 treatment were screened for inclusion in the study. The valuable prognostic liver-function-based indicators were selected using Cox proportional hazards regression analysis to build a novel liver-function-indicators-based signature (LFIS). Concordance index (C-index), the area under the receiver operating characteristic (ROC) curve (AUC), and Kaplan-Meier survival curves were utilized to access the predictive performance of LFIS. RESULTS: A total of 434 HCC patients who received anti-PD-1 treatment were included in the study. The LFIS, based on alkaline phosphatase-to-albumin ratio index, Child-Pugh score, platelet-albumin score, aspartate aminotransferase-to-lymphocyte ratio index, and gamma-glutamyl transpeptidase-to-lymphocyte ratio index, was constructed and identified as an independent risk factor for patient survival. The C-index of LFIS for overall survival (OS) was 0.692, which was higher than the other single liver-function-based indicator. The AUC of LFIS at 6-, 12-, 18-, and 24-month were 0.74, 0.714, 0.747, and 0.865 for OS, respectively. Patients in the higher-risk LFIS group were associated with both worse OS and PFS. An online and easy-to-use calculator was further constructed for better application of the LFIS signature. CONCLUSION: The LFIS score had an excellent prognosis prediction ability superior to every single liver-function-based indicator for anti-PD-1 treatment in HCC patients. It is a reliable, easy-to-use tool to stratify risk for OS and PFS in HCC patients who received anti-PD-1 treatment.

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Background: Salmonella enteritidis (S. enteritidis), a zoonotic pathogen with a broad host range, presents a substantial threat to global public health safety. Vaccination stands as an effective strategy for the prevention and control of S. enteritidis infection, highlighting an immediate clinical need for the creation of safe and efficient attenuated live vaccines. Methods: In this study, a S. enteritidis peptidoglycan-associated lipoprotein (pal) gene deletion strain (Δpal), was constructed. To assess its virulence, we conducted experiments on biofilm formation capability, motility, as well as cell and mouse infection. Subsequently, we evaluated the immune-protective effect of Δpal. Results: It was discovered that deletion of the pal gene reduced the biofilm formation capability and motility of S. enteritidis. Cell infection experiments revealed that the Δpal strain exhibited significantly decreased abilities in invasion, adhesion, and intracellular survival, with downregulation of virulence gene expression, including mgtC, invH, spvB, sipA, sipB, ssaV, csgA, and pipB. Mouse infection experiments showed that the LD50 of Δpal increased by 104 times, and its colonization ability in mouse tissue organs was significantly reduced. The results indicated that the pal gene severely affected the virulence of S. enteritidis. Further, immunogenicity evaluation of Δpal showed a significant enhancement in the lymphocyte transformation proliferation capability of immunized mice, producing high titers of specific IgG and IgA, suggesting that Δpal possesses good immunogenicity. Challenge protection tests demonstrated that the strain could provide 100% immune protection against wild-type strains in mice. Discussion: This study proves that the pal gene influences the virulence of S. enteritidis, and Δpal could serve as a candidate strain for attenuated live vaccines, laying the foundation for the development of attenuated live vaccines against Salmonella.

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Background: Autosomal dominant hyper-IgE syndrome (AD-HIES) is a rare genetic syndrome that alters typical post-operative wound healing. AD-HIES patients are prone to develop persistent air leaks (PALs) due to bronchopleural fistulas. This report is unique in that it describes a novel approach to managing PALs in this complex population. Case Description: Two patients with AD-HIES were identified in the setting of a PAL. The first patient was a 31-year-old male with recurrent pneumonia, who developed a large hydropneumothorax following re-presentation with fever and cough. A chest tube was inserted, which required continuous suction in the setting of what developed into a PAL. Subsequently, an endobronchial valve (EBV) was deployed to successfully manage the PAL. The second patient was a 25-year-old male, who developed a post-operative large volume air leak following a complicated surgical resection of a giant pneumatocele. Several attempts of placing multiple EBVs were required to finally address the PAL. In both cases, EBVs were successfully employed to manage and eventually resolve symptoms caused by PAL. Conclusions: Our experience suggests that EBVs are successful in treating PAL in the setting of AD-HIES, which often manifests as highly complex scenarios. Hence, EBVs represent a valuable addition to the therapeutic armamentarium against recalcitrant PAL. EBVs were well-tolerated in patients afflicted by AD-HIES, with no progressive infections noted. Both patients ultimately were able to resolve their PAL following placement of the EBV.

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There is a growing trend towards enhancing the post-harvest shelf life and maintaining the nutritional quality of horticultural products using eco-friendly methods. Raspberries are valued for their diverse array of phenolic compounds, which are key contributors to their health-promoting properties. However, raspberries are prone to a relatively short post-harvest lifespan. The present study aimed to investigate the effect of exogenous melatonin (MEL; 0, 0.001, 0.01, and 0.1 mM) on decay control and shelf-life extension. The results demonstrated that MEL treatment significantly reduced the fruit decay rate (P ≤ 0.01). Based on the findings, MEL treatment significantly increased titratable acidity (TA), total phenolics content (TPC), total flavonoid content (TFC), and total anthocyanin content (TAC). Furthermore, the MEL-treated samples showed increased levels of rutin and quercetin content, as well as antioxidant activity as measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reduction activity potential (FRAP). Additionally, the samples exhibited higher levels of phenylalanine ammonia-lyase (PAL) and catalase (CAT) enzymes compared to the control samples. Moreover, the levels of pH, total soluble solids (TSS), and IC50 were decreased in the MEL-treated samples (P ≤ 0.01). The highest amount of TA (0.619 g/100 ml juice), rutin (16.722 µg/ml juice) and quercetin (1.467 µg/ml juice), and PAL activity (225.696 nm/g FW/min) was observed at 0.001 mM treatment, while, the highest amount of TAC (227.235 mg Cy-g/100 ml juice) at a concentration of 0.01 mM and CAT (0.696 u/g FW) and TAL activities (9.553 nm/100 g FW) at a concentration of 0.1 mM were obtained. Considering the lack of significant differences in the effects of melatonin concentrations and the low dose of 0.001 mM, this concentration is recommended for further research. The hierarchical cluster analysis (HCA) and principal component analysis (PCA) divided the treatments into three groups based on their characteristics. Based on the Pearson correlation between TPC, TFC, TAC, and TAA, a positive correlation was observed with antioxidant (DPPH and FRAP) and enzyme (PAL and CAT) activities. The results of this study have identified melatonin as an eco-friendly compound that enhances the shelf life of raspberry fruits by improving phenolic compounds, as well as antioxidant and enzyme activities.

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The majority of the world's natural rubber comes from the rubber tree (Hevea brasiliensis). As a key enzyme for synthesizing phenylpropanoid compounds, phenylalanine ammonia-lyase (PAL) has a critical role in plant satisfactory growth and environmental adaptation. To clarify the characteristics of rubber tree PAL family genes, a genome-wide characterization of rubber tree PALs was conducted in this study. Eight PAL genes (HbPAL1-HbPAL8), which spread over chromosomes 3, 7, 8, 10, 12, 13, 14, 16, and 18, were found to be present in the genome of H. brasiliensis. Phylogenetic analysis classified HbPALs into groups I and II, and the group I HbPALs (HbPAL1-HbPAL6) displayed similar conserved motif compositions and gene architectures. Tissue expression patterns of HbPALs quantified by quantitative real-time PCR (qPCR) proved that distinct HbPALs exhibited varying tissue expression patterns. The HbPAL promoters contained a plethora of cis-acting elements that responded to hormones and stress, and the qPCR analysis demonstrated that abiotic stressors like cold, drought, salt, and H2O2-induced oxidative stress, as well as hormones like salicylic acid, abscisic acid, ethylene, and methyl jasmonate, controlled the expression of HbPALs. The majority of HbPALs were also regulated by powdery mildew, anthracnose, and Corynespora leaf fall disease infection. In addition, HbPAL1, HbPAL4, and HbPAL7 were significantly up-regulated in the bark of tapping panel dryness rubber trees relative to that of healthy trees. Our results provide a thorough comprehension of the characteristics of HbPAL genes and set the groundwork for further investigation of the biological functions of HbPALs in rubber trees.

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Susceptibility is defined as the disruption of host defence systems that promotes infection or limits pathogenicity. Glutathione (GSH) is a major component of defence signalling pathways that maintain redox status and is synthesised by γ-glutamyl cysteine synthetase (γ-ECS). On the other hand, lignin acts as a barrier in the primary cell wall of vascular bundles (VBs) synthesised by phenylalanine ammonia-lyase (PAL) in the intracellular system of plants. In this study, we used two inhibitors, such as L-Buthionine-sulfoximine (BSO), which irreversibly inhibits γ-ECS, and 2,4-dichlorophenoxyacetic acid (DPA), which reduces PAL activity and leads to the induction of oxidative stress in wheat (Triticum aestivum) seedlings after exposure to Fusarium oxysporum. Seedlings treated with 1 mM L-BSO and 2,4-DPA showed high levels of hydrogen peroxide (H2O2), malondialdehyde (MDA), carbonyl (CO) content, and low activity of antioxidative enzymes [superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR)] as compared to wild-type (WT) seedlings under F. oxysporum infection. Further, the content of reduced glutathione (RGSH), ascorbate (ASC), and lignin was decreased in BSO and DPA treated seedlings as compared to WT seedlings during Fusarium infection. Moreover, treatment with BSO and DPA significantly inhibited the relative activity of γ-ECS and PAL (P ≤ 0.001) in WT seedlings during Fusarium infection, which led to disintegrated VBs and, finally, cell death. Our results demonstrate that inhibition of γ-ECS and PAL by BSO and DPA, respectively, disrupts the defence mechanisms of wheat seedlings and induces susceptibility to F. oxysporum.

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The mechanism underlying the ability of rice to germinate underwater is a largely enigmatic but key research question highly relevant to rice cultivation. Moreover, although rice is known to accumulate salicylic acid (SA), SA biosynthesis is poorly defined, and its role in underwater germination is unknown. It is also unclear whether peroxisomes, organelles essential to oilseed germination and rice SA accumulation, play a role in rice germination. Here, we show that submerged imbibition of rice seeds induces SA accumulation to promote germination in submergence. Two submergence-induced peroxisomal Oryza sativa cinnamate:CoA ligases (OsCNLs) are required for this SA accumulation. SA exerts this germination-promoting function by inducing indole-acetic acid (IAA) catabolism through the IAA-amino acid conjugating enzyme GH3. The metabolic cascade we identified may potentially be adopted in agriculture to improve the underwater germination of submergence-intolerant rice varieties. SA pretreatment is also a promising strategy to improve submerged rice germination in the field.

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Introduction: Parkinson's disease (PD) is the most common motor neurodegenerative disease worldwide. Given the complexity of PD etiology and the different metabolic derangements correlated to the disease, metabolomics profiling of patients is a helpful tool to identify patho-mechanistic pathways for the disease development. Dopamine metabolism has been the target of several previous studies, of which some have reported lower phenylalanine and tyrosine levels in PD patients compared to controls. Methods: In this study, we have collected plasma from 27 PD patients, 18 reference controls, and 8 high-risk controls to perform a metabolomic study using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). Results: Our findings revealed higher intensities of trans-cinnamate, a phenylalanine metabolite, in patients compared to reference controls. Thus, we hypothesize that phenylalanine metabolism has been shifted to produce trans-cinnamate via L-phenylalanine ammonia lyase (PAL), instead of producing tyrosine, a dopamine precursor, via phenylalanine hydroxylase (PAH). Discussion: Given that these metabolites are precursors to several other metabolic pathways, the intensities of many metabolites such as dopamine, norepinephrine, and 3-hydroxyanthranilic acid, which connects phenylalanine metabolism to that of tryptophan, have been altered. Consequently, and in respect to Metabolic Control Analysis (MCA) theory, the levels of tryptophan metabolites have also been altered. Some of these metabolites are tryptamine, melatonin, and nicotinamide. Thus, we assume that these alterations could contribute to the dopaminergic, adrenergic, and serotonergic neurodegeneration that happen in the disease.