Re-initialization-free Level Set Method via Molecular Beam Epitaxy Equation Regularization for Image Segmentation

Variational level set method has become a powerful tool in image segmentation due to its ability to handle complex topological changes and maintain continuity and smoothness in the process of evolution. However its evolution process can be unstable, which results in over flatted or over sharpened contours and segmentation failure. To improve the accuracy and stability of evolution, we propose a high-order level set variational segmentation method integrated with molecular beam epitaxy (MBE) equation regularization. This method uses the crystal growth in the MBE process to limit the evolution of the level set function, and thus can avoid the re-initialization in the evolution process and regulate the smoothness of the segmented curve. It also works for noisy images with intensity inhomogeneity, which is a challenge in image segmentation. To solve the variational model, we derive the gradient flow and design scalar auxiliary variable (SAV) scheme coupled with fast Fourier transform (FFT), which can significantly improve the computational efficiency compared with the traditional semi-implicit and semi-explicit scheme. Numerical experiments show that the proposed method can generate smooth segmentation curves, retain fine segmentation targets and obtain robust segmentation results of small objects. Compared to existing level set methods, this model is state-of-the-art in both accuracy and efficiency

Usage of Cell-Free Protein Synthesis in Post-Translational Modification of μ-Conopeptide PIIIA

The post-translational modifications of conopeptides are the most complicated modifications to date and are well-known and closely related to the activity of conopeptides. The hydroxylation of proline in conopeptides affects folding, structure, and biological activity, and prolyl 4 hydroxylase has been characterized in Conus literatus. However, the hydroxylation machinery of proline in conopeptides is still unclear. In order to address the hydroxylation mechanism of proline in μ-PIIIA, three recombinant plasmids encoding different hybrid precursors of μ-PIIIA were constructed and crossly combined with protein disulfide isomerase, prolyl 4 hydroxylase, and glutaminyl cyclase in a continuous exchange cell-free protein system. The findings showed that prolyl 4 hydroxylase might recognize the propeptide of μ-PIIIA to achieve the hydroxylation of proline, while the cyclization of glutamate was also formed. Additionally, in Escherichia coli, the co-expression plasmid encoding prolyl 4 hydroxylase and the precursor of μ-PIIIA containing pro and mature regions were used to validate the continuous exchange cell-free protein system. Surprisingly, in addition to the two hydroxyproline residues and one pyroglutamyl residue, three disulfide bridges were formed using Trx as a fusion tag, and the yield of the fusion peptide was approximately 20 mg/L. The results of electrophysiology analysis indicated that the recombinant μ-PIIIA without C-terminal amidate inhibited the current of hNaV1.4 with a 939 nM IC50. Our work solved the issue that it was challenging to quickly generate post-translationally modified conopeptides in vitro. This is the first study to demonstrate that prolyl 4 hydroxylase catalyzes the proline hydroxylation through recognition in the propeptide of μ-PIIIA, and it will provide a new way for synthesizing multi-modified conopeptides with pharmacological activity

A new staging system for postoperative prognostication in pancreatic ductal adenocarcinoma

Summary: The current TNM staging system for pancreatic ductal adenocarcinoma (PDAC) has revised the definitions of T and N categories as well as stage groups. However, studies validating these modifications have yielded inconsistent results. The existing TNM staging system in prognostic prediction remains unsatisfactory. The prognosis of PDAC is closely associated with pathological and biological factors. Herein, we propose a new staging system incorporating distant metastasis, postoperative serum levels of CA19-9 and CEA, tumor size, lymph node metastasis, lymphovascular involvement, and perineural invasion to enhance the accuracy of prognosis assessment. The proposed staging system exhibited a strong correlation with both overall survival and recurrence-free survival, effectively stratifying survival into five distinct tiers. Additionally, it had favorable discrimination and calibration. Thus, the proposed staging system demonstrates superior prognostic performance compared to the TNM staging system, and can serve as a valuable complementary tool to address the limitations of TNM staging in prognostication

Implementing the free HPV vaccination for adolescent girls aged below 14 in Shenzhen, Guangdong Province of China: experience, challenges, and lessons

Abstract Cervical cancer is a major public health concern in China, accounting for almost one-fifth of the global incidence and mortality. The recently prequalified domestic bivalent human papillomavirus (HPV) vaccine offers a practical and feasible preventive measure. In response to the global call for action, the National Health Commission issued an Action Plan to eliminate cervical cancer by 2030, with promotion of the HPV vaccination for school-aged girls as a critical step. Despite this, implementation of the vaccination has been patchy, with very low coverage among eligible girls. To address this, from December 2021 to December 2022, a demonstration project was launched in Shenzhen, Guangdong Province, to promote the inclusion of HPV vaccine in local immunisation programme and to address existing barriers to implementation. Using multiple sources of data, this article presents a case study of the demonstration project, analysing its impact on rolling out HPV vaccination among eligible girls and identifying any challenges encountered during implementation. The demonstration project has shown promising results in increasing the HPV vaccination rate, promoting public awareness and acceptance of the domestic HPV vaccine, and establishing a model for quickly scaling up the vaccination at the municipal level. The success of the project can be attributed to several factors, including strong governmental commitment, sufficient funding, multi-sectoral collaboration, ensured vaccine accessibility and affordability, improved vaccination services, and effective health education and communication strategies. Lessons learned from Shenzhen can provide valuable insights for future advocacy and implementation of the vaccination in other areas of China, but challenges must be addressed to achieve universal coverage. These include addressing vaccine hesitancy, expanding the programme to cover a broader age range, and ensuring consistent quality of vaccination services in primary care facilities. Overcoming these challenges will require innovative strategies, public-private partnerships, and sustained funding and resources. Future research should focus on evaluating the long-term effectiveness of the vaccination programme and identifying contextual factors that may impact its implementation in different settings. Overall, the effective control of cervical cancer in China will rely on the “political will” to ensure the incorporation of preventive interventions into policies and universal programme coverage

First case report of pustules associated with Escherichia fergusonii in the chinese pangolin (Manis pentadactyla aurita)

Abstract Background Escherichia fergusonii is a common conditionally pathogenic bacterium that infects humans and animals. E. fergusonii has been reported to cause diarrhea, respiratory disease, and septicemia, but it is rarely reported to cause skin infections in animals. E. fergusonii has been isolated from the skin and muscular tissue of Chinese pangolin (Manis pentadactyla aurita). To date, there have been no reports of Chinese pangolins with clinical signs of skin diseases. Case presentation This case report describes the clinical case of a subadult (bodyweight: 1.1 kg) female Chinese pangolin from wild rescue with pustules and subcutaneous suppurative infection due to E. fergusonii in the abdominal skin. Bacterial culture, Biochemical analysis, PCR and histopathology were utilized to identify the bacteria in the pustule puncture fluid and infected tissue. To the best of our knowledge, this is the first report of E. fergusonii-related pustules on a Chinese pangolin. Conclusion This case report presents the first observed skin infection in a Chinese pangolin. E. fergusonii infection should be considered as a possible differential diagnosis of pustules and subcutaneous suppurative skin conditions in Chinese pangolins, and we also provide several recommendations for the diagnosis and treatment of this disease