Improved performance of a fiber-optic hydrogen sensor based on a controllable optical heating technology.

A novel, to the best of our knowledge, and compact fiber-optic hydrogen sensor based on light intensity demodulation and controllable optical heating technology is proposed and experimentally investigated. This system employs three photodetectors for optic signal transformation. The first PD is used to receive a little fraction of the amplified spontaneous emission (ASE) for calibration, and the second PD is utilized to detect optic signal reflected by a single mode fiber deposited with WO3-Pd2Pt-Pt composite film. The last PD is utilized to receive the optical power reflected by the short fiber Bragg grating (SFBG) with a central wavelength located in a steep wavelength range (the intensity decreases approximately linearly with the increase of the wavelength) of the ASE light source. A 980 nm laser and proportion integration differentiation (PID) controller were employed to ensure the hydrogen sensitive film working at an operating temperature of 60°C. This sensing system can display a quick response time of 0.4 s toward 10,000 ppm hydrogen in air. In addition, the detection limit of 5 ppm in air can be achieved with this sensing system. The stability of this sensor can be greatly enhanced with a controllable optical heating system, which can greatly promote its potential application in various fields.

Single-Port Robotic Trans-Subxiphoid Surgery for Anterior Mediastinal Disease: A Pilot Trial.

OBJECTIVE: In recent years, there has been an increasing focus on minimally invasive mediastinal surgery using a trans-subxiphoid single-port thoracoscopic approach. Despite its potential advantages, the widespread adoption of this method has been hindered by the intricate surgical maneuvers required within the confined retrosternal space. Robotic surgery offers the potential to overcome the limitations inherent in the thoracoscopic technique. METHODS: This was a clinical trial (NCT05455840) to evaluate the feasibility and safety of utilizing the da Vinci® SP system (Intuitive Surgical, Sunnyvale, CA, USA) for trans-subxiphoid single-port surgery in patients with anterior mediastinal disease. The primary endpoints encompassed conversion rates and the secondary endpoints included the occurrence of perioperative complications. RESULTS: Between August 2022 and April 2023, a total of 15 patients (7 men and 8 women; median age = 56 years, interquartile range [IQR]: 49 to 65 years) underwent trans-subxiphoid robotic surgery using da Vinci SP platform for maximal thymectomy (n = 2) or removal of anterior mediastinal masses (n = 13). All surgical procedures were carried out with success, with no need for conversion to open surgery or the creation of additional ports. The median docking time was 2 min (IQR: 1 to 4 min), while the console time had a median of 152 min (IQR: 95 to 191 min). There were no postoperative complications and patients experienced a median postoperative hospital stay of 2 days with no unplanned 30-day readmission. CONCLUSIONS: This study shows that trans-subxiphoid single-port robotic surgery employing the da Vinci SP system in patients with anterior mediastinal disease is clinically viable with acceptable safety and short-term outcomes.

Association between visceral obesity index and diabetes: a systematic review and meta-analysis.

CONTENT: The correlation between visceral obesity index (VAI) and diabetes and accuracy of early prediction of diabetes are still controversial. OBJECTIVE: This study aims to review the relationship between high level of VAI and diabetes, and early predictive value of diabetes. DATA SOURCES: The databases of PubMed, Cochrane, Embase, and Web of Science were searched until October 17, 2023. STUDY SELECTION: After adjusting for confounding factors, the original study on the association between VAI and diabetes was analyzed. DATA EXTRACTION: We extracted odds ratio (OR) between VAI and diabetes management after controlling for mixed factors, and the sensitivity, specificity and diagnostic four grid table for early prediction of diabetes. DATA SYNTHESIS: 53 studies, comprising 595,946 participants were included. The findings of the meta-analysis elucidated that in cohort studies, a high VAI significantly increased the risk of diabetes mellitus in males (OR = 2.83 (95% CI: 2.30-3.49)) and females (OR = 3.32 (95% CI: 2.48-4.45)). The ROC, sensitivity, and specificity of VAI for early prediction of diabetes in males were 0.64 (95% CI: 0.62-0.66), 0.57 (95% CI: 0.53-0.61), and 0.65 (95% CI: 0.61-0.69), respectively, and 0.67 (95% CI: 0.65-0.69), 0.66 (95% CI: 0.60-0.71), and 0.61 (95% CI: 0.57-0.66) in females, respectively. CONCLUSIONS: VAI is an independent predictor of the risk of diabetes, yet its predictive accuracy remains limited. In future studies, determine whether VAI can be utilized in conjunction with other related indicators to early predict the risk of diabetes, to enhance the accuracy of prediction of the risk of diabetes.

3D VSP Imaging Using DAS Recording of P- and S-Waves in Vertical and Lateral Well Sections in West Texas.

A 3D vertical seismic profiling (VSP) survey was acquired using a distributed acoustic sensing (DAS) system in the Permian Basin, West Texas. In total, 682 shot points from a pair of vibroseis units were recorded using optical fibers installed in a 9000 ft (2743 m) vertical part and 5000 ft (1524 m) horizontal reach of a well. Transmitted and reflected P, S, and converted waves were evident in the DAS data. From first-break P and S arrivals, we found average P-wave velocities of approximately 14,000 ft/s (4570 m/s) and S-wave velocities of 8800 ft/s (3000 m/s) in the deep section. We modified the conventional geophone VSP processing workflow and produced P-P reflection and P-S volumes derived from the well's vertical section. The Wolfcamp formation can be seen in two 3D volumes (P-P and P-S) from the vertical section of the well. They cover an area of 3000 ft (914 m) in the north-south direction and 1500 ft (460 m) in the west-east direction. Time slices showed coherent reflections, especially at 1.7 s (~11,000 ft), which was interpreted as the bottom of the Wolfcamp formation. Vp/Vs values from 2300 ft (701 m) -8800 ft (2682 m) interval range were between 1.7 and 2.0. These first data provide baseline images to compare to follow-up surveys after hydraulic fracturing as well as potential usefulness in extracting elastic properties and providing further indications of fractured volumes.

Role played by MDSC in colitis-associated colorectal cancer and potential therapeutic strategies.

Colitis-associated colorectal cancer has been a hot topic in public health issues worldwide. Numerous studies have demonstrated the significance of myeloid-derived suppressor cells (MDSCs) in the progression of this ailment, but the specific mechanism of their role in the transformation of inflammation to cancer is unclear, and potential therapies targeting MDSC are also unclear. This paper outlines the possible involvement of MDSC to the development of colitis-associated colorectal cancer. It also explores the immune and other relevant roles played by MDSC, and collates relevant targeted therapies against MDSC. In addition, current targeted therapies for colorectal cancer are analyzed and summarized.

KLF4 Inhibits the Activation of Human Hepatic Stellate Cell In Vitro.

OBJECTIVE: Hepatic stellate cells (HSCs) play a crucial role in liver fibrosis. Early-stage liver fibrosis is reversible and intimately associated with the state of HSCs. Kruppel-like factor 4 (KLF4) plays a pivotal role in a wide array of physiological and pathological processes. This study aimed to investigate the effect of KLF4 on the proliferation, apoptosis and phenotype of quiescent HSCs METHODS: We designed a KLF4 lentiviral vector and a KLF4 siRNA lentiviral vector, to upregulate and silence KLF4 expression in human HSC LX-2 cells via transfection. Cell proliferation was assessed using the CCK-8 assay. Flow cytometry was used to detect the cell cycle distribution and apoptosis rate. Western blotting was used to determine the levels of some quiescence and activation markers of HSCs RESULTS: Overexpression of KLF4 significantly increased the levels of E-cadherin and ZO-1, which are quiescent HSC markers, while significantly decreased the levels of N-cadherin and a-SMA, known activated HSC markers. In contrast, cell proliferation and apoptosis rates were elevated in LX-2 cells in which KLF4 expression was silenced CONCLUSION: KLF4 inhibits the proliferation and activation of human LX-2 HSCs. It might be a key regulatory protein in the maintenance of HSC quiescence and may serve as a target for the inhibition of hepatic fibrosis.

Survival Outcomes of Patients with Esophageal Cancer and Post-chemoradiotherapy Surgical T4b Disease: Is Palliative Resection Justified?

BACKGROUND: In patients with locally advanced esophageal cancer who had undergone chemoradiotherapy (CRT), the limitations of radiological evaluation may necessitate surgical exploration to ascertain disease resectability. Upon intraoperative confirmation of T4b disease (sT4b), the optimal management strategy remains unclear. While some surgeons may opt against resection, others advocate for palliative esophagectomy (PE). Regrettably, the current literature does not provide a consensus on the most effective approach for managing these intricate cases. METHODS: The study cohort consisted of 68 patients with esophageal squamous cell carcinoma (ESCC) who presented with sT4b disease following CRT. The perioperative outcomes and overall survival (OS) were compared between patients who underwent PE (n = 56) and those who received an open-close (OC) procedure (n = 12). RESULTS: Patients who underwent an OC procedure experienced a shorter hospital stay (16.5 vs. 28.8 days; p = 0.052) and showed a non-significant reduction in the rate of major complications (33.9% vs. 25%; p = 0.549) and in-hospital mortality (0% vs. 5.4%; p = 0.412) than those who received PE; however, PE was associated with a superior 2-year OS rate than OC (9.6% vs. 0%; p = 0.009). In multivariable analysis, a pretreatment clinical stage of II/III (hazard ratio [HR] 0.51, 95% confidence interval [CI] 0.31-0.87; p = 0.013) and PE with retrosternal reconstruction (HR 0.38, 95% CI 0.15-0.49; p = 0.010) were independently associated with a more favorable OS. CONCLUSION: PE with retrosternal reconstruction may be a feasible approach for patients with ESCC exhibiting sT4b disease after CRT.

Pathological response to neoadjuvant chemoradiotherapy for oesophageal squamous cell carcinoma in Eastern versus Western countries: meta-analysis.

OBJECTIVE: Locally advanced oesophageal squamous cell carcinoma can be treated with neoadjuvant chemoradiotherapy or chemotherapy followed by oesophagectomy. Discrepancies in pathological response rates have been reported between studies from Eastern versus Western countries. The aim of this study was to compare the pathological response to neoadjuvant chemoradiotherapy in Eastern versus Western countries. METHODS: Databases were searched until November 2022 for studies reporting pCR rates after neoadjuvant chemoradiotherapy for oesophageal squamous cell carcinoma. Multi-level meta-analyses were performed to pool pCR rates separately for cohorts from studies performed in centres in the Sinosphere (East) or in Europe and the Anglosphere (West). RESULTS: For neoadjuvant chemoradiotherapy, 51 Eastern cohorts (5636 patients) and 20 Western cohorts (3039 patients) were included. Studies from Eastern countries included more men, younger patients, more proximal tumours, and more cT4 and cN+ disease. Patients in the West were more often treated with high-dose radiotherapy, whereas patients in the East were more often treated with a platinum + fluoropyrimidine regimen. The pooled pCR rate after neoadjuvant chemoradiotherapy was 31.7% (95% c.i. 29.5% to 34.1%) in Eastern cohorts versus 40.4% (95% c.i. 35.0% to 45.9%) in Western cohorts (fixed-effect P = 0.003). For cohorts with similar cTNM stages, pooled pCR rates for the East and the West were 32.5% and 41.9% respectively (fixed-effect P = 0.003). CONCLUSION: The pathological response to neoadjuvant chemoradiotherapy is less favourable in patients treated in Eastern countries compared with Western countries. Despite efforts to investigate accounting factors, the discrepancy in pCR rate cannot be entirely explained by differences in patient, tumour, or treatment characteristics.

The impact of the length of proximal margin on the prognosis in adenocarcinoma of gastroesophageal junction: A real-world study and strategies.

BACKGROUND: The optimal proximal margin (PM) length for Siewert II/III adenocarcinoma of the esophagogastric junction (AEJ) remains unclear. This study aimed to determine the optimal PM length using an abdominal approach to guide surgical decision-making. METHODS: A prospective study analyzed 304 consecutive patients diagnosed with Siewert II/III AEJ between January 2019 and December 2021. Total gastrectomy was performed via the abdominal approach, and PM length was measured on fixed gross specimens. X-Tile software determined the optimal PM cut-point based on progression-free survival (PFS). Univariate analyses compared baseline characteristics across PM groups, while survival analyses utilized Kaplan-Meier estimation and Cox proportional hazards regression for assessing the impact of margin length on survival. Multivariable analyses were conducted to adjust for confounding variables. RESULTS: The study included 264 AEJ cases classified as Siewert II (71.97%) or III (28.03%). The median gross PM length was 1.0 cm (IQR: 0.5 cm-1.5 cm, range: 0 cm-6 cm). PM length ≥1.2 cm was associated with a lower risk of disease progression compared to PM length 0.4 cm on PFS (HR = 0.41, 95% CI 0.20-0.84, P = 0.015). Moreover, PM ≥ 1.2 cm improved prognosis in subgroups of T4 or N3, tumor size <4 cm, Siewert II, and Lauren classification. CONCLUSIONS: For Siewert type II/III AEJ, a proximal margin length ≥1.2 cm (1.65 cm in situ) is associated with improved outcomes. These findings offer valuable insights into the association between PM length and outcomes in Siewert II/III AEJ, providing guidance for surgical approaches and aiding clinical decision-making to enhance patient outcomes.

Incidence and Predictors of Textbook Outcome after Minimally Invasive Esophagectomy for Cancer: A Two-Center Study.

PURPOSE: The textbook outcome (TBO), a multidimensional indicator that reflects an optimal perioperative course, has emerged as a significant prognostic variable in surgical oncology. Our study aimed to assess the occurrence and determinants of TBO following minimally invasive esophagectomy (MIE) for cancer. METHODS: A total of 945 patients who had undergone MIE at two high-volume centers between 2008 and 2022 were analyzed. Multivariable logistic regression analysis was applied to identify the independent predictors of TBO. The potential selection bias associated with choosing between different MIE techniques-namely, robotic esophagectomy (RE) and video-assisted thoracoscopic esophagectomy (VATE)-was addressed by applying inverse probability of treatment weighting (IPTW). RESULTS: TBO was realized in 46.6% of cases (n = 440), correlating with markedly better overall and disease-free survival. Multivariable analysis showed that treatment with RE (odds ratio (OR) = 1.527; 95% confidence interval (CI) = 1.149-2.028) was associated with a higher likelihood of achieving TBO, whereas a Charlson Comorbidity Index (CCI) of 2 or higher showed an opposite association (CCI2: OR = 0.687, 95% CI = 0.483-0.977; CCI ≥ 3: OR = 0.604, 95% CI = 0.399-0.915). The advantage of RE in attaining a higher rate of TBO, compared to VATE, remained statistically significant after applying IPTW, with rates of 53.3% for RE and 42.2% for VATE. Notably, RE contributed to a greater probability of thorough lymph node dissection, resection with negative margins, and the avoidance of major complications. CONCLUSION: TBO was realized in 46.6% of the patients who underwent MIE for cancer. Patients with a lower CCI and those who received RE were more likely to achieve TBO.

Co-targeting CD47 and VEGF elicited potent anti-tumor effects in gastric cancer.

BACKGROUND: CD47, serving as an intrinsic immune checkpoint, has demonstrated efficacy as an anti-tumor target in hematologic malignancies. Nevertheless, the clinical relevance of CD47 in gastric cancer and its potential as a therapeutic target remains unclear. METHODS: The expression of CD47 in clinical gastric cancer tissues was assessed using immunohistochemistry and Western blot. Patient-derived cells were obtained from gastric cancer tissues and co-cultured with macrophages derived from human peripheral blood mononuclear cells. Flow cytometry analyses were employed to evaluate the rate of phagocytosis. Humanized patient-derived xenografts (Hu-PDXs) models were established to assess the efficacy of anti-CD47 immunotherapy or the combination of anti-CD47 and anti-VEGF therapy in treating gastric cancer. The infiltrated immune cells in the xenograft were analyzed by immunohistochemistry. RESULTS: In this study, we have substantiated the high expression of CD47 in gastric cancer tissues, establishing a strong association with unfavorable prognosis. Through the utilization of SIRPα-Fc to target CD47, we have effectively enhanced macrophage phagocytosis of PDCs in vitro and impeded the growth of Hu-PDXs. It is noteworthy that anti-CD47 immunotherapy has been observed to sustain tumor angiogenic vasculature, with a positive correlation between the expression of VEGF and CD47 in gastric cancer. Furthermore, the successful implementation of anti-angiogenic treatment has further augmented the anti-tumor efficacy of anti-CD47 therapy. In addition, the potent suppression of tumor growth, prevention of cancer recurrence after surgery, and significant prolongation of overall survival in Hu-PDX models can be achieved through the simultaneous targeting of CD47 and VEGF using the bispecific fusion protein SIRPα-VEGFR1 or by combining the two single-targeted agents. CONCLUSIONS: Our preclinical studies collectively offer substantiation that CD47 holds promise as a prospective target for gastric cancer, while also highlighting the potential of anti-angiogenic therapy to enhance tumor responsiveness to anti-CD47 immunotherapy.

Fluorescence-guided thoracoscopic surgery for postoperative chylothorax: A technical note with video vignette.

TECHNIQUE: The surgical management for high-output postoperative chylothorax typically necessitates ligation of the thoracic duct (TD) above the leak site and/or sealing the leak with a clip. However, pinpointing these structures during subsequent surgeries can be challenging due to their variable course and the presence of traumatized tissues surrounding the leak area. In response to this, we have developed a novel, fluorescence-guided technique that significantly enhances intraoperative identification of the leak point and the TD. This method was applied in the case of a 52-year-old man suffering from refractory chylothorax following a previous lung cancer surgery. This study documents the surgical procedure and includes a video vignette for a comprehensive understanding. RESULTS: A bilateral inguinal lymph node injection of saline (10 mL), guided by ultrasound and containing 2.5 mg/mL indocyanine green (ICG), was administered 20 min prior to surgery. During thoracoscopic exploration, the leak point was precisely pinpointed in the right paratracheal area by transitioning from bright light to fluorescent mode. The TD was clearly identified, and upon ligation, there was no further leakage of fluorescent lymph, indicating a successful closure of the lymphatic structure. The surgery proceeded uneventfully, and the patient was able to resume oral intake on the third postoperative day. There was no evidence of recurring symptoms, leading to his discharge. CONCLUSION: The intralymphatic injection of ICG offers a rapid visualization of the TD's anatomy and can effectively pinpoint the leak point, even amidst traumatized tissues. Moreover, it provides prompt feedback on the efficacy of ligation.

Recent advances in functional micro/nanomaterials for removal of crude oil via thermal effects.

Crude oil is one of the most widely used energy and industrial raw materials that is crucial to the world economy, and is used to produce various petroleum products. However, crude oil often spills during extraction, transportation and use, causing negative impacts on the environment. Thus, there is a high demand for products to remediate leaked crude oil. Among them, oleophilic and hydrophobic adsorbents can absorb crude oil through thermal effects and are research hotspots. In this review, we first present an overview of wettability theory, the heating principles of various thermal effects, and the theory of reducing crude oil viscosity by heating. Then we discuss adsorbents based on different heating methods including the photothermal effect, Joule heating effect, alternating magnetic field heating effect, and composite heating effect. Preparation methods and oil adsorption performance of adsorbents are summarized. Finally, the advantages and disadvantages of various heating methods are briefly summarized, as well as the prospects for future research.

Recent advances in the potential effects of natural products from traditional Chinese medicine against respiratory diseases targeting ferroptosis.

Respiratory diseases, marked by structural changes in the airways and lung tissues, can lead to reduced respiratory function and, in severe cases, respiratory failure. The side effects of current treatments, such as hormone therapy, drugs, and radiotherapy, highlight the need for new therapeutic strategies. Traditional Chinese Medicine (TCM) offers a promising alternative, leveraging its ability to target multiple pathways and mechanisms. Active compounds from Chinese herbs and other natural sources exhibit anti-inflammatory, antioxidant, antitumor, and immunomodulatory effects, making them valuable in preventing and treating respiratory conditions. Ferroptosis, a unique form of programmed cell death (PCD) distinct from apoptosis, necrosis, and others, has emerged as a key area of interest. However, comprehensive reviews on how natural products influence ferroptosis in respiratory diseases are lacking. This review will explore the therapeutic potential and mechanisms of natural products from TCM in modulating ferroptosis for respiratory diseases like acute lung injury (ALI), asthma, pulmonary fibrosis (PF), chronic obstructive pulmonary disease (COPD), lung ischemia-reperfusion injury (LIRI), pulmonary hypertension (PH), and lung cancer, aiming to provide new insights for research and clinical application in TCM for respiratory health.

Airflow Triggered Water Film Self-Sculpturing on Femtosecond Laser-Induced Heterogeneously Wetted Micro/Nanostructured Surfaces.

Liquid manipulation is essential for daily life and modern industry, and it is widely used in various fields, including seawater desalination, microfluidic robots, and biomedical engineering. Nevertheless, the current research focuses on the manipulation of individual droplets. There are a few projects for water film management. Here, we proposed a facile method of wind-triggered water film self-sculpturing based on a heterogeneous wettability surface, which is achieved by the femtosecond laser direct writing technology and femtosecond laser deposition. Under the conditions of various airflow velocities and water film thicknesses, three distinct behaviors of the water film were analyzed. As a result, when the water film thickness is lower than 4.9 mm, the self-sculpture process will occur until the whole superhydrophobic surface dewetting. Four potential applications are demonstrated, including encryption, oil containers, reconfigurable patterning, and self-splitting devices. This work provides a new approach for manipulating a water film of fluid control engineering.

A porous micro/nano-structured polyethylene film prepared using a picosecond laser for agricultural passive cooling.

Passive cooling materials, as a promising choice for mitigating the global energy crisis, have limited use as their cooling effects are usually weakened or lost by dust contamination. In this study, a passive cooling polyethylene (PE) film with self-cleaning properties is prepared by picosecond laser ablation. Numerous root-like hierarchical porous micro/nano-structures were obtained on the double side of the PE film. The outside (toward air) shows excellent self-cleaning, corrosion resistance, and anti-friction properties. The inside (towards crops) further reduced the transmittance and water vapor evaporation (keeping the soil moist). Compared with the pristine PE film, the transmittance of the as-prepared double-sided micro/nano-structured PE film decreased by about 40%. In addition, during the crop cultivation experiment, the temperature of the crop leaves was reduced by 2.7-7 °C and showed a higher plant height and greater leaf width under the cover of the laser-treated film. This demonstrates that the passive cooling PE film has an excellent temperature regulation ability and good practical application effects. This study proposes a simple strategy based on a picosecond laser for the preparation of passive cooling materials, which are beneficial for alleviating energy crises and promoting sustainable development.

Robot-assisted surgery outperforms video-assisted thoracoscopic surgery for anterior mediastinal disease: a multi-institutional study.

Anterior mediastinal procedures are increasingly being performed using robot-assisted thoracic surgery (RATS) or video-assisted thoracoscopic surgery (VATS). While both approaches have shown superior outcomes compared to open surgery, their comparative benefits are not as distinct. The aim of this retrospective study was to bridge this knowledge gap using a multicenter dataset. Patients who underwent elective minimally invasive surgery for anterior mediastinal disease between 2015 and 2022 were deemed eligible. The study participants were grouped based on whether a robot was used or not, and perioperative outcomes were compared. To mitigate selection bias, inverse probability of treatment weighting (ITPW) was applied using the propensity score. The final analysis included 312 patients (RATS = 120; VATS = 192). Following the application of IPTW, RATS was found to be associated with a longer operating time (215.3 versus 139.31 min, P < 0.001), fewer days with a chest tube (1.96 versus 2.61 days, P = 0.047), and a shorter hospital stay (3.03 versus 3.91 days, P = 0.041) compared to VATS. Subgroup analyses indicated that the benefit of RATS in reducing the length of hospital stay was particularly pronounced in patients with tumors larger than 6 cm (mean difference [MD] = - 2.28 days, P = 0.033), those diagnosed with myasthenia gravis (MD = - 3.84 days, P = 0.002), and those who underwent a trans-subxiphoid surgical approach (MD = - 0.81 days, P = 0.04). Both VATS and RATS are safe and effective approaches for treating anterior mediastinal disease. However, RATS holds distinct advantages over VATS including shorter hospital stays and reduced chest tube drainage periods.

Selection and identification of a prohibitin 2-binding DNA aptamer for tumor tissue imaging and targeted chemotherapy.

Tumor cell-targeting molecules play a vital role in cancer diagnosis, targeted therapy, and biomarker discovery. Aptamers are emerging as novel targeting molecules with unique advantages in cancer research. In this work, we have developed several DNA aptamers through cell-based systematic evolution of ligands by exponential enrichment (Cell-SELEX). The selected SYL-6 aptamer can bind to a variety of cancer cells with high signal. Tumor tissue imaging demonstrated that SYL-6-Cy5 fluorescent probe was able to recognize multiple clinical tumor tissues but not the normal tissues, which indicates great potential of SYL-6 for clinical tumor diagnosis. Meanwhile, we identified prohibitin 2 (PHB2) as the molecular target of SYL-6 using mass spectrometry, pull-down and RNA interference assays. Moreover, SYL-6 can be used as a delivery vehicle to carry with doxorubicin (Dox) chemotherapeutic agents for antitumor targeted chemotherapy. The constructed SYL-6-Dox can not only selectively kill tumor cells in vitro, but also inhibit tumor growth with reduced side effects in vivo. This work may provide a general tumor cell-targeting molecule and a potential biomarker for cancer diagnosis and targeted therapy.

Intracellular polyamines regulate redox homeostasis with cAMP-PKA signalling during sexual mating/filamentation and pathogenicity of Sporisorium scitamineum.

Sugarcane smut caused by Sporisorium scitamineum seriously impairs sugarcane production and quality. Sexual mating/filamentation is a critical step of S. scitamineum pathogenesis, yet the regulatory mechanisms are not fully understood. In this study, we identified the SsAGA, SsODC, and SsSAMDC genes, which are involved in polyamine biosynthesis in S. scitamineum. Deletion of SsODC led to complete loss of filamentous growth after sexual mating, and deletion of SsAGA or SsSAMDC caused reduced filamentation. Double deletion of SsODC and SsSAMDC resulted in auxotrophy for putrescine (PUT) and spermidine (SPD) when grown on minimal medium (MM), indicating that these two genes encode enzymes that are critical for PUT and SPD biosynthesis. We further showed that low PUT concentrations promoted S. scitamineum filamentation, while high PUT concentrations suppressed filamentation. Disrupted fungal polyamine biosynthesis also resulted in a loss of pathogenicity and reduced fungal biomass within infected plants at the early infection stage. SPD formed a gradient from the diseased part to nonsymptom parts of the cane stem, suggesting that SPD is probably favourable for fungal virulence. Mutants of the cAMP-PKA (SsGPA3-SsUAC1-SsADR1) signalling pathway displayed up-regulation of the SsODC gene and elevated intracellular levels of PUT. SsODC directly interacted with SsGPA3, and sporidia of the ss1uac1ΔodcΔ mutant displayed abundant pseudohyphae. Furthermore, we found that elevated PUT levels caused accumulation of intracellular reactive oxygen species (ROS), probably by suppressing transcription of ROS-scavenging enzymes, while SPD played the opposite role. Overall, our work proves that polyamines play important roles in the pathogenic development of sugarcane smut fungus, probably by collaboratively regulating intracellular redox homeostasis with the cAMP-PKA signalling pathway.