The Potential Valorization of Corn Stalks by Alkaline Sequential Fractionation to Obtain Papermaking Fibers, Hemicelluloses, and Lignin-A Comprehensive Mass Balance Approach.

The current study deals with an examination of strategies for the sequential treatment of corn stalks (CSs) in an integrated manner aiming to obtain papermaking fibers and to recover both lignin and hemicelluloses (HCs). Several pathways of valorization were experimentally trialed, focusing on getting information from mass balance analysis in an attempt to reveal the potential outcomes in terms of pulp yield, chemical composition, and papermaking properties such as tensile and burst strength. The raw lignin amounts and purity as well as separated hemicelluloses were also characterized. In this work, pulp yields in the range of 44-50% were obtained from CSs, while lignin and hemicelluloses yielded maximum values of 10 g/100 g of CS and 6.2 g/100 g of CS, respectively. Other findings of mass balance analysis evidenced that besides the papermaking pulp, the lignin and HCs also have interesting output values. The recovered lignin yield values were shown to be less than 50% in general, meaning that even if 67 to 90% of it is removed from CSs, only about half is recovered. The removal rates of hemicelluloses were found to be in the range of approx. 30 to 60%. About 15 to 25% of the original HCs could be recovered, and polysaccharides-based products with 67 to 75% xylan content could be obtained. Some key opinions were developed regarding how the mass balance could turn as a result of the chosen CS valorization set-up. The determined antioxidant activity showed that both lignin and hemicelluloses had interesting values for IC50.

Impact of SARS-CoV-2 Pandemic on the Diagnosis of Cervical Cancer and Precursor Lesions-A Single-Center Retrospective Study.

Background and Objectives: Our aim was to perform a retrospective analysis of the volume of cervical screening tests, the number of patients treated with an excision method, and the incidence of invasive and non-invasive cervical during a pandemic and pre-pandemic period of 24 months. Materials and Methods: The study compared 404 patients who underwent cervical cone biopsy for cervical cancer. The study examined patients' specimens based on histopathological characteristics and categorized cervical lesions based on pap smear. Results: There was a statistically significant age difference between the two study periods. The mean difference was 32 years before the pandemic and 35 years during the pandemic (p-value > 0.05). The biggest patient loss ratio identified by age group was in the 50-59-year group, with a 14.53% loss in the pre-pandemic period and a 9.1% loss in the pandemic period. In the pandemic period, patients from rural areas presented in the clinical trial with a lower rate of 39.52% (83 patients) vs. 60.47% (127 patients) in urban areas. A higher percentage of patients experiencing cervicorrhagia as a clinical manifestation in the pandemic period vs. the pre-pandemic period, with an increase in more severe lesions in the pandemic period, had a statistical significance of 8% more newly diagnosed compared to the pre-pandemic period. Conclusions: The addressability of the patients during the COVID period was not affected in a drastic way in our study. We encountered a decrease in appointments in the age group of 50-59 years and a decrease in patients with rural residence. In our study, we found an increase in cervical bleeding as a reason for consultation in the pandemic period with a higher lesion degree, both on a pap smear and on a cervical biopsy.

Heterogeneity of Cervical Cancer-Associated Tertiary Lymphoid Structures (TLSs) and Their Specific Interrelation With Clinicopathological Parameters.

OBJECTIVE: The study investigates morphological variants of tertiary lymphoid structures (TLSs) in relation to cervical cancer development, from intraepithelial neoplastic lesions to invasive carcinomas with locoregional lymph node metastases. MATERIALS AND METHODS: This retrospective analysis comprised 100 cervical cancer cases who had had total hysterectomy with lymphadenectomy in the Obstetrics and Gynecology Clinic of the Municipal Emergency Clinical Hospital of Timisoara, Romania, from 2020 to 2023. Bilateral ilio obturator lymphadenectomy and total hysterectomy were used to acquire biopsy samples. The presence of germinal centers, other stromal structures, TLS density, topography relative to the tumor lesion, and malignant cell islets are used to evaluate and classify TLS. RESULTS: We first globally evaluated the total number of TLSs (TLS.T). We observed topographically two places in the cervical stroma: TLS immediately peritumorally positioned and TLS away from tumor lesions. Invasive carcinomas have bigger superficial TLSs with a well-defined germinal center. As they approached the tumor, TLSs increased in size and density. We also detected a special type of TLS associated with nerve fibers, which we named tertiary lymphoid structures associated with nerves (TLS.N). The total number of TLSs did not correlate with age, but 85.71% of patients presenting TLS.N were aged between 59 and 72 years old. Our findings showed a strong correlation between age (postmenopausal, p = 0.005) and TLS-N presence. Similarly, TLS parameters evolved with tumor differentiation. Only in the TLS.N group did the tumoral grading (G) 3 correlate with TLS (p = 0.041), while TLS.T did not correlate with G. All TLS.N. patients, except one, had lymphovascular invasion and massive histiocytosis. On the first point, TLS.N correlated with lymphovascular invasion (p = 0.032). CONCLUSION: Tertiary lymphoid structures associated with nerves have not been previously reported in cervical cancer, and their effects on prognosis and aggression are unknown. There was a substantial association between TLSs.N presence and age over 60, suggesting it is exclusive to menopausal women. They were also substantially connected with lymphovascular invasion and G3, suggesting they may be a poor cervical cancer prognostic factor.

Clinical Outcomes and Molecular Predictors of Pembrolizumab (Keytruda) as a PD-1 Immune Checkpoint Inhibitor in Advanced and Metastatic Cervical Cancer: A Systematic Review and Meta-Analysis.

This systematic review evaluates the clinical outcomes and molecular predictors of response to pembrolizumab in patients with advanced and metastatic cervical cancer. We adhered to the PRISMA guidelines for systematic reviews, conducting a database search in PubMed, Scopus, and Embase. The eligibility criteria centered on clinical outcomes, including the overall survival (OS), progression-free survival (PFS), and immune-related biomarkers post-pembrolizumab therapy. We included both prospective and retrospective studies that detailed clinical outcomes and molecular characteristics predictive of therapeutic response. Our search yielded six studies involving 846 patients treated with pembrolizumab from 2017 to 2022. The meta-analysis of these studies showed that pembrolizumab, used as monotherapy or in combination with chemotherapy, extended the OS by a weighted median of 10.35 months and the PFS by 8.50 months. The treatment demonstrated a pooled objective response rate (ORR) of 22.39%, although the I2 test result of 67.49% showed a high heterogeneity among the studies. Notably, patients with high PD-L1 expression (CPS ≥ 10) experienced improved outcomes in terms of the PFS and OS. The most common complications were fatigue, diarrhea, and immune-related adverse events. Pembrolizumab significantly enhances clinical outcomes in metastatic cervical cancer, particularly among patients with high PD-L1 expression. The drug maintains a good safety profile, reinforcing its treatment potential for patients with advanced and metastatic cervical cancer. Future studies should explore long-term effects and strategies to integrate pembrolizumab optimally into current treatment regimens, aiming to maximize patient benefits and effectively manage side effects.

Optimization of Alkaline Extraction of Xylan-Based Hemicelluloses from Wheat Straws: Effects of Microwave, Ultrasound, and Freeze-Thaw Cycles.

The alkaline extraction of hemicelluloses from a mixture of three varieties of wheat straw (containing 40.1% cellulose, 20.23% xylan, and 26.2% hemicellulose) was analyzed considering the following complementary pre-treatments: freeze-thaw cycles, microwaves, and ultrasounds. The two cycles freeze-thaw approach was selected based on simplicity and energy savings for further analysis and optimization. Experiments planned with Design Expert were performed. The regression model determined through the response surface methodology based on the severity factor (defined as a function of time and temperature) and alkali concentration as variables was then used to optimize the process in a multi-objective case considering the possibility of further use for pulping. To show the properties and chemical structure of the separated hemicelluloses, several analytical methods were used: high-performance chromatography (HPLC), Fourier-transformed infrared spectroscopy (FTIR), proton nuclear magnetic resonance spectroscopy (1H-NMR), thermogravimetry and derivative thermogravimetry analysis (TG, DTG), and scanning electron microscopy (SEM). The verified experimental optimization result indicated the possibility of obtaining hemicelluloses material containing 3.40% glucan, 85.51% xylan, and 7.89% arabinan. The association of hot alkaline extraction with two freeze-thaw cycles allows the partial preservation of the hemicellulose polymeric structure.

Integrated Hemicellulose Extraction and Papermaking Fiber Production from Agro-Waste Biomass.

The present study deals with the valorization of corn stalks in an integrated processing strategy targeting two products: extracted hemicelluloses (HC) and papermaking fibers. Preliminary trials were conducted to assess the individual or the combined effects of biomass treatment on the quality of the obtained hemicelluloses and papermaking fibers. Depending on the hot alkaline extraction (HAE) conditions, the extracted HC had a xylan content between 44-63%. The xylan removal yield ranged between 19-35%. The recovery of HC from the extraction liquor and final black liquor was significantly affected by process conditions. The experimental approach continued with the study of HAE conditions on the obtained paper's mechanical properties. The optimization approach considered conserving paper strength properties while achieving an equilibrium with the highest possible HC extraction yield. The optimal values are sodium hydroxide concentration (1%), process time (33 min), and temperature (100 °C). The xylan content in the separated HC sample was ~55%. An extended extraction of HC from the resulting pulp under hot alkaline conditions with 5% NaOH was performed to prove the HC influence on paper strength. The xylan content in HC samples was 65%. The consequence of xylan content reduction in pulp leads to 30-50% mechanical strength loss.