Improving the thermal stability and catalytic activity of ulvan lyase by the combination of FoldX and KnowVolution campaign.

Thermal stability is one of the most important properties of ulvan lyases for their application in algae biomass degradation. The Knowledge gaining directed eVolution (KnowVolution) protein engineering strategy could be employed to improve thermostability of ulvan lyase with less screening effort. Herein, the unfolding free energies (ΔΔG) of the loop region were calculated using FoldX and four sites (D103, G104, T113, Q229) were selected for saturation mutagenesis, resulting in the identification of a favorable single-site mutant Q229M. Subsequently, iteration mutation was carried out with the mutant N57P (previously obtained by our group) to further enhance the performance of ulvan lyase. The results showed that the most beneficial variant N57P/Q229M exhibited a 1.67-fold and 2-fold increase in residual activity compared to the wild type after incubation at 40 °C and 50 °C for 1 h, respectively. In addition, the variant produced 1.06 mg/mL of reducing sugar in 2 h, which was almost four times as much as the wild type. Molecular dynamics simulations revealed that N57P/Q229M mutant enhanced the structural rigidity by augmenting intramolecular hydrogen bonds. Meanwhile, the shorter proton transmission distance between the general base of the enzyme and the substrate contributed to the glycosidic bond breakage. Our research showed that in silico saturation mutagenesis using position scan module in FoldX allowed for faster screening of mutants with improved thermal stability, and combining it with KnowVolution enabled a balanced effect of thermal stability and enzyme activity in protein engineering.

Analysis of influencing factors on vibration characteristics of electro-hydraulic vibration cutting system.

The cutting process of the cantilever tunneling machine mainly generates excitation through the cutting motor or the hydraulic cylinder driven by the hydraulic system. Regardless of the driving method, the frequency width of the excitation system is limited, difficult to control, and the excitation effect is poor. Therefore, in order to improve excavation efficiency, the excitation system parallel to the original cutting and rotating system is designed. Based on the excitation characteristics caused by alternating fluid flow, the core component of the excitation system, hydraulic exciter, is designed, and the dynamics and dynamic characteristics of the excitation system are analyzed. Based on AMESim software, analyze the impact of factors such as pump displacement, excitation frequency, and pipeline parameters on the operational performance of the electro-hydraulic vibration cutting system, and conduct experimental verification by building a cutting test bench. The experimental results show that as the inner diameter of the pipeline increases, the fluctuation at the acceleration turning point decreases in each cycle and approaches the peak faster. As the excitation frequency increases, the cutting acceleration of the electro-hydraulic excitation cutting system decreases first and then increases, verifying the accuracy of the simulation results. In the experiment, it was found that the acceleration transformation range of the cutting head of the excitation system is the smallest and most stable when the excitation frequency is 30 Hz. In order to verify that the excitation frequency of 30 Hz is the optimal frequency, further contact force tests were conducted on the cutting teeth. It was found that when the hydraulic excitation system adds a 30 Hz excitation frequency, the contact force on the cutting teeth is the smallest. It is more conducive to reducing the damage and wear of the cutting head, and the cutting effect of the cutting head is more obvious. The research results are beneficial for improving the cutting performance of the electro-hydraulic excitation cutting system, providing theoretical support for the selection of cutting parameters for excavation machinery and hydraulic excitation, and improving the existing theoretical system for active excitation cutting vibration analysis of excavation machines.

Global Epidemiological Features of Human Monkeypox Cases and Their Associations With Social-Economic Level and International Travel Arrivals: A Systematic Review and Ecological Study.

Objectives: We aimed to evaluate global epidemiological features of human monkeypox (mpox) cases and their associations with social-economic level and international travel arrivals. Methods: We estimated the pooled value by random-effects models. Then, we conducted an ecological study to evaluate the relationship of confirmed cases with social-economic indices and international travel arrivals using correlation analyses. Results: The average age (2022: 35.52, 95% CI [28.09, 42.94] vs. before 2022: 18.38, 95% CI [14.74, 22.02]) and comorbidity rate (2022: 15.7%, 95% CI [8.9%, 22.4%] vs. before 2022: 14.9%, 95% CI [8.5%, 21.3%]) of mpox cases in the 2022 human mpox outbreak were significantly higher than those of cases before 2022. During the 2022 mpox outbreak, the proportion of men who have sex with men (MSM) was high (79.8%, 95% CI [65.5%, 94.2%]). The number of confirmed mpox cases in 2022 significantly correlated with high social-economic levels and international travel arrivals (all p < 0.05). Conclusion: Our findings highlighted the importance of early surveillance and timely detection in high-risk populations, including older people, MSM, and travelers, which is crucial to curb the wide transmission of mpox.

Cross-linked enzyme aggregates immobilization: preparation, characterization, and applications.

Enzymes are commonly used as biocatalysts for various biological and chemical processes. However, some major drawbacks of free enzymes (e.g. poor reusability and instability) significantly restrict their industrial practices. How to overcome these weaknesses remain considerable challenges. Enzyme immobilization is one of the most effective ways to improve the reusability and stability of enzymes. Cross-linked enzyme aggregates (CLEAs) has been known as a novel and versatile carrier-free immobilization method. CLEAs is attractive due to its simplicity and robustness, without purification. It generally shows: high catalytic specificity and selectivity, good operational and storage stabilities, and good reusability. Moreover, co-immobilization of different kinds of enzymes can be acquired. These CLEAs advantages provide opportunities for further industrial applications. Herein, the preparation parameters of CLEAs were first summarized. Next, characterization of structural and catalytic properties, stability and reusability are also proposed. Finally, some important applications of this technique in: environmental protection, industrial chemistry, food industry, and pharmaceutical synthesis and delivery are introduced. Potential challenges and future research directions, such as improving cross-linking efficiency and internal mass transfer efficiency, are also presented. This implies that CLEAs provide an efficient and feasible technique to improve the properties of enzymes for use in the industry.

lncRNA GAS5 Sensitizes Breast Cancer Cells to Ionizing Radiation by Inhibiting DNA Repair.

Radioresistance of breast cancer is a major reason for therapeutic failure and limits further increases in the dose of radiation due to severe adverse effects. Recently, long noncoding RNAs (lncRNAs) have been shown to regulate cancer proliferation, chemoresistance, and radioresistance. Among these lncRNAs, lncRNA GAS5 expression was shown to be downregulated in breast cancer and related to trastuzumab resistance. However, its role in the radiation response is unclear. In this study, we demonstrated that lncRNA GAS5 expression was reduced in irradiated cells and that overexpression of GAS5 reduced cell viability and promoted cell apoptosis after irradiation. Moreover, overexpression of GAS5 resulted in increased G2/M arrest and unrepaired DNA damage, indicating a radiosensitizing role of GAS5 in breast cancer cells. Finally, we found that a GAS5-interacting miRNA, miR-21, reversed the radiosensitizing effects of GAS5 by inhibiting the apoptotic pathway. In conclusion, we found that lncRNA GAS5 sensitized breast cancer cells to ionizing radiation by inhibiting DNA repair and suppressing miR-21, identifying novel targets for breast cancer radiosensitization.

Outcome evaluation of neoadjuvant chemotherapy in patients with stage IB2 or IIA cervical cancer: a retrospective comparative study.

BACKGROUND: To study the benefits of neoadjuvant chemotherapy (NACT) in addition to surgical resection and postoperative chemoradiotherapy (CRT) in patients with stage IB2 or IIA cervical cancer. METHODS: We retrospectively analyzed 363 patients with stage IB2 or IIA cervical cancer that received the surgical resection and postoperative CRT with or without NACT at the Second Hospital of Jilin University between February 2014 and December 2016. We chose mortality as the primary outcome, and the clinical deterioration as secondary outcome. These outcomes were compared between two groups of patients with or without NACT by univariate or multivariate logistic regression analysis. RESULTS: Among the 363 identified patients, 114 patients were in the neoadjuvant group and 249 patients in the non-neoadjuvant group. The median follow-up period was 36.4 months, ranging from 28 to 55 months. There were statistically significant differences in the tumor differentiation, clinical stages, vascular tumor thrombus, and postoperative radiotherapy between these two group patients. After adjusting for these variables, patients in the neoadjuvant group had a statistically significantly lower survival rate than those in the non-neoadjuvant group within one year after the treatment, but this difference disappeared at the 3-year follow-up period. Also, more patients in the neoadjuvant group experienced clinical deterioration at the 3-year follow-up period. CONCLUSIONS: NACT did not show significant benefits in mortality and clinical deterioration in patients with stage IB2 or IIA cervical cancer.

Neurological paraneoplastic syndrome caused by small cell lung cancer: a case report.

Paraneoplastic syndrome (PNS) is a term used to describe pathological changes in organ function among patients with malignancy that does not metastasize. Clinical manifestations affect nerve, digestive, hematopoietic, endocrine, bone, joint, and urinary function. Here we present the case of a 59-year-old male with PNS as the initial symptom of SCLC. PNS symptoms manifested as repeated attacks after surgery and chemotherapy. The severity of the patient's symptoms has rarely been reported. The tumor type involved most frequently is small-cell lung cancer (SCLC). Symptoms caused by PNS typically manifest earlier than those caused by the tumor. Immunohistochemical staining was positive for Syn, CgA, CD56, TTF-1, CK (AE1/AE3), Hu antibodies, and Ki67 (90%). Treatment remains challenging. A case of severe Neurological PNS caused by early small cell carcinoma was reported. Although the patient accepted surgery and postoperative radiotherapy and chemotherapy, symptoms persist. In this case report, treatment with pregabalin and antidepressant agents improved the patient's numbness. Currently, the patient has been followed-up for >3 years without any signs of recurrence and PNS. This case may inform future treatment of patients with PNS.

Comparison of accuracy and long-term prognosis between computed tomography-based and magnetic resonance imaging-based brachytherapy for cervical cancer: A meta-analysis.

High-dose-rate brachytherapy (HDR-BT) has been shown to play an important role in the treatment of cervical cancer patients. The aim of this systematic review and meta-analysis was to compare the dose parameters and long-term effects of MRI-based, CT-based and hybrid imaging (MRI/CT)-based volumetric planning. A systematic search was conducted to identify the clinical studies of BT treatment on cervical cancer patients. After study selection, a total of 13 clinical studies were enrolled for further analysis. No obvious differences were observed among the treatment parameters and the patients included. In detail, no significant difference was observed among these three techniques of volumetric planning in the parameters of high-risk clinical target volume (HR-CTV), total dose of D90 or mean fraction dose of D90. Meanwhile, MRI-based planning was superior to CT-based treatment in the total dose D2cc to organs at risk (OAR) for the bladder, rectum and sigmoid. Furthermore, no significant difference was observed among MRI-, CT- or hybrid-based treatments with the mean fraction dose D2cc to OAR for the bladder, rectum or sigmoid. In conclusion, MRI provides good anatomical delineation of the relevant HR-CTV and OAR, and performed better in the analyses of dose parameters compared with CT. At least one MR image is required to assess the tumour extension, with clinical findings and MRI information facilitating much more accurate CT-based contouring.

Neoadjuvant chemotherapy does not improve the prognosis and lymph node metastasis rate of locally advanced cervical squamous cell carcinoma: A retrospective cohort study in China.

Locally advanced cervical carcinoma has a poor prognosis. Neoadjuvant chemotherapy (NACT) can reduce tumor size and improve tumor resection rate, but its use in large locally advanced cervical carcinoma is controversial. This study aimed to evaluate the treatment and prognosis of NACT in patients with cervical carcinoma stage IB2 or IIA2.This was a retrospective cohort study of patients who underwent type-C radical surgery and pelvic lymphadenectomy due to cervical carcinoma stage IB2/IIA2 between 2/2014 and 12/2016 at the Second Hospital of Jilin University. The patients were grouped according to whether they received NACT (paclitaxel and a platinum salt) or not. Overall survival (OS) and progression-free survival (PFS) were compared between the 2 groups.Of the 144 patients, 60 (41.7%) received NACT. A total of 119 patients underwent postoperative radiation therapy, of which 97 received radiation therapy alone and 22 received concurrent chemoradiotherapy. The adverse reactions in the NACT group were mainly hematologic toxic reactions, but were tolerated. No grade ≥III adverse reactions were observed. NACT did not significantly affect the PFS (P = .453) and OS (P = .933) between the 2 groups. No factor was found to be independently associated with OS or PFS (all P > .05).Compared with patients who underwent surgery with/without radiotherapy and/or chemotherapy, NACT using paclitaxel and a platinum salt does not improve the prognosis and lymph node metastasis rate of locally advanced cervical carcinoma in Chinese patients.

Prognostic value of lymphovascular space invasion in patients with early stage cervical cancer in Jilin, China: A retrospective study.

The metastasis of cervical carcinoma is associated with the lymphovascular spread. The primary objective of the present study was to determine the prognostic value of lymphovascular space invasion (LVSI) in patients with early-stage cervical cancer in Jilin, China.In this retrospective cohort study, patients with early-stage cervical cancer (stage IB-IIA) at the Second Hospital of Jilin University from February 2014 to December 2016 were included in the analysis. All included participants underwent radical hysterectomy with pelvic lymphadenectomy. LVSI was identified by hematoxylin and eosin (H&E) staining. The primary outcomes are overall survival (OS) and progression-free survival (PFS). Kaplan-Meier curves were used to calculate the patient's survival. Survival was compared using the log-rank test, while risk factors for the prognosis were assessed by Cox regression analysis.The incidence of LVSI was positively associated with the depth of stromal invasion (P = .009) and lymph node metastasis (LNM, P < .001). LVSI is an independent factor that affects OS (P = .009) and PFS (P = .006) in patients with early stage cervical cancer. LNM status is an independent factor that affects postoperative OS (P = .005).The incidence of lymphatic vessel infiltration is positively associated with the depth of stromal invasion and LNM. LVSI is an independent risk factor for the prognosis of early cervical cancer. The results suggest that further large-scale studies are needed to improve the treatment for patients with LVSI.

Axillary lymph node metastasis as the first manifestation of male occult breast cancer: A Case Report.

RATIONAL: Occult breast cancer (OBC) is an extremely rare breast cancer and is defined by the presence of axillary metastasis without a primary tumor in the breasts or any abnormality on radiologic examination. PATIENT CONCERNS: This case report presents a 49-year-old man who was diagnosed with male OBC, which first manifested as an axillary lymph node metastasis followed by the emergence of infraclavicular lymph node metastasis. Neither the breast nor other organs had any abnormality. DIAGNOSIS: The pathological examination revealed metastatic adenocarcinoma. Immunohistochemical (IHC) staining results were positive for estrogen receptor (ER), progesterone receptor (PR), and gross cystic disease fluid protein-15 (GCDFP-15); and negative for human epidermal receptor-2 (Her-2) 1+, cytokeratin (CK) 7, CK20, and thyroid transcription factor-1 (TTF-1). INTERVENTIONS: The patient underwent left axillary lymph node dissection but not a mastectomy. After the operation, the patient subsequently underwent chemotherapy, radiotherapy, and endocrinotherapy. OUTCOMES: Currently, he has been followed-up for >4 years without any signs of recurrence. LESSONS: Careful physical and imaging examinations combined with pathological analysis are essential in the diagnosis of male OBC. Early surgery remains the primary treatment.

Increased invasion and tumorigenicity capacity of CD44+/CD24- breast cancer MCF7 cells in vitro and in nude mice.

BACKGROUND: Identification of cancer stem cells (CSCs) and their behaviors will provide insightful information for the future control of human cancers. This study investigated CD44 and CD24 cell surface markers as breast cancer CSC markers in vitro and in vivo. METHODS: Flow cytometry with CD44 and CD24 markers was used to sort breast cancer MCF7 cells for scanning electron microscopy (SEM), tumor cell invasion assay, and nude mouse xenograft assay. RESULTS: Flow cytometry assay using CD44 and CD24 markers sorted MCF7 cells into four subsets, i.e., CD44+/CD24-/low, CD44-/CD24+, CD44+/CD24+, and CD44-/CD24-. The SEM data showed that there were many protrusions on the surface of CD44+/CD24-/low cells. CD44+/CD24-/low cells had many microvilli and pseudopodia. The CD44+/CD24-/low cells had a higher migration and invasion abilities than that of the other three subsets of the cells. The in vivo tumor formation assay revealed that CD44+/CD24- cells had the highest tumorigenic capacity compared to the other three subsets. CONCLUSION: CD44 and CD24 could be useful markers for identification of breast CSCs because CD44+/CD24-/low cells had unique surface ultrastructures and the highest tumorigenicity and invasive abilities.