Spatial-temporal patterns and influencing factors for hemorrhagic fever with renal syndrome: A 16-year national surveillance analysis in China.

Background: China is confronted with the significant menace posed by hemorrhagic fever with renal syndrome (HFRS). Nevertheless, the long-term spatial-temporal variations, regional prevalence patterns, and fundamental determinants' mechanisms for HFRS remain inadequately elucidated. Methods: Newly diagnosed cases of HFRS from January 2004 to December 2019 were acquired from the China Public Health Science Data repository. We used Age-period-cohort and Bayesian Spacetime Hierarchy models to identify high-risk populations and regions in mainland China. Additionally, the Geographical Detector model was employed to quantify the determinant powers of significant driver factors to the disease. Results: A total of 199,799 cases of HFRS were reported in mainland China during 2004-2019. The incidence of HFRS declined from 1.93 per 100,000 in 2004 to 0.69 per 100,000 in 2019. The incidence demonstrated an inverted U-shaped trend with advancing age, peaking in the 50-54 age group, with higher incidences observed among individuals aged 20-74 years. Hyperendemic areas were mainly concentrated in the northeastern regions of China, while some western provinces exhibited a potential upward trend. Geographical detector model identified that the spatial variations of HFRS were significantly associated with the relative humidity (Q = 0.36), forest cover (Q = 0.26), rainfall (Q = 0.18), temperature (Q = 0.16), and the surface water resources (Q = 0.14). Conclusions: This study offered comprehensive examinations of epidemic patterns, identified high-risk areas quantitatively, and analyzed factors influencing HFRS transmission in China. The findings may contribute to the necessary implementations for the effective prevention and control of HFRS.

Changes in the global epidemiological characteristics of cystic echinococcosis over the past 30 years and projections for the next decade: Findings from the Global Burden of Disease Study 2019.

Background: Despite ongoing changes in the global epidemiology of cystic echinococcosis (CE), there is a lack of research conducted to date. Methods: We extracted data on incidence and disability-adjusted life years for 204 countries and territories from 1990 to 2019 to evaluate the epidemiological characteristics and burden of CE through the Global Burden of Diseases, Injuries, and Risk Factors Study 2019. We used locally weighted linear regression to analyse the primary driving factors of the prevalence of CE at the national and regional levels and utilised a Bayesian Age-Period-Cohort model to forecast the global incidence of CE in the next decade. Results: Globally, the incidence of CE remained constantly high from 1990 (2.65 per 100 000 population) to 2019 (2.60 per 100 000 population), resulting in an estimated 207 368 new cases in 2019. We observed substantial variations in the disease burden regarding its spatiotemporal distribution, population demographics, and Socio-Demographic Index levels. According to established models, factors such as health care capacity, livestock husbandry, agricultural activities, rural populations, and education levels are likely to play significant roles in determining the prevalence of CE across different countries. By 2030, the worldwide number of CE cases could reach as high as 235 628, representing an increase of 13.63% compared to 2019. Conclusions: Over the past three decades, the global burden of CE has persistently remained high, especially in Central Asia, as well as North Africa and the Middle East. Efforts should focus on more effective prevention and control measures in these key regions and should specifically target vulnerable populations to prevent the escalation of epidemics.

Conformational Switch of the 250s Loop Enables the Efficient Transglycosylation in GH Family 77.

Amylomaltases (AMs) play important roles in glycogen and maltose metabolism. However, the molecular mechanism is elusive. Here, we investigated the conformational dynamics of the 250s loop and catalytic mechanism of Thermus aquaticus TaAM using path-metadynamics and QM/MM MD simulations. The results demonstrate that the transition of the 250s loop from an open to closed conformation promotes polysaccharide sliding, leading to the ideal positioning of the acid/base. Furthermore, the conformational dynamics can also modulate the selectivity of hydrolysis and transglycosylation. The closed conformation of the 250s loop enables the tight packing of the active site for transglycosylation, reducing the energy penalty and efficiently preventing the penetration of water into the active site. Conversely, the partially closed conformation for hydrolysis results in a loosely packed active site, destabilizing the transition state. These computational findings guide mutation experiments and enable the identification of mutants with an improved disproportionation/hydrolysis ratio. The present mechanism is in line with experimental data, highlighting the critical role of conformational dynamics in regulating the catalytic reactivity of GHs.

Mechanistic Insights into How the Protonation State of D234 Dictates the Reactivity in Streptomyces coelicolor ß-N-Acetylhexosaminidase.

ß-N-Acetylhexosaminidases (HEXs) play important roles in human diseases and the biosynthesis of human milk oligosaccharides. Despite extensive research, the catalytic mechanism of these enzymes remains largely unexplored. In this study, we employed quantum mechanics/molecular mechanics metadynamics to investigate the molecular mechanism of Streptomyces coelicolor HEX (ScHEX), which has shed light on the transition state structures and conformational pathways of this enzyme. Our simulations revealed that Asp242, located near the assisting residue, can switch the reaction intermediate to an oxazolinium ion or a neutral oxazoline, depending on the protonation state of the residue. Moreover, our findings indicated that the free energy barrier of the second-step reaction starting from the neutral oxazoline increases steeply due to the reduction in the anomeric carbon positive charge and the shortening of the C1-O2N bond. Our results provide valuable insights into the mechanism of substrate-assisted catalysis and could facilitate the design of inhibitors and the engineering of analogous glycosidases for biosynthesis.

Multiple approaches of loop region modification for thermostability improvement of 4,6-α-glucanotransferase from Limosilactobacillus fermentum NCC 3057.

4,6-α-glucanotransferase (4,6-α-GT), as a member of the glycoside hydrolase 70 (GH70) family, converts starch/maltooligosaccharides into α,1-6 bond-containing α-glucan and possesses potential applications in food, medical and related industries but does not satisfy the high-temperature requirement due to its poor thermostability. In this study, a 4,6-α-GT (ΔGtfB) from Limosilactobacillus fermentum NCC 3057 was used as a model enzyme to improve its thermostability. The loops of ΔGtfB as the target region were optimized using directed evolution, sequence alignment, and computer-aided design. A total of 11 positive mutants were obtained and iteratively combined to obtain a combined mutant CM9, with high resistance to temperature (50 °C). The activity of mutant CM9 was 2.08-fold the activity of the wild type, accompanied by a 5 °C higher optimal temperature, a 5.76 °C higher melting point (Tm, 59.46 °C), and an 11.95-fold longer half-life time (t1/2). The results showed that most of the polar residues in the loop region of ΔGtfB are mutated into rigid proline residues. Molecular dynamics simulation demonstrated that the root mean square fluctuation of CM9 significantly decreased by "Breathing" movement reduction of the loop region. This study provides a new strategy for improving the thermostability of 4,6-α-GT through rational loop region modification.

High prevalence of unawareness of HCV infection status among both HCV-seronegative and seropositive people living with human immunodeficiency virus in Taiwan.

OBJECTIVES: HCV infection status awareness is crucial in the HCV care continuum for both HCV-seropositive (HCV-positive status awareness) and seronegative (HCV-negative status awareness) populations. However, trends in the unawareness of HCV infection status (UoHCV) remain unknown in HIV-positive patients. This study investigated UoHCV prevalence, the associated factors of UoHCV, and its association with HCV-related knowledge in HIV-positive patients. METHODS: For this cross-sectional, multicenter, questionnaire-based study, 844 HIV-infected participants were recruited from three hospitals in Taiwan from June 2018 to March 2020. Participants were grouped by HCV serostatus (HCV-seronegative [n = 734] and HCV-seropositive [n = 110]) and categorized by their HIV diagnosis date (before 2008, 2008-2013, and 2014-2020). Exploratory factor analysis was used to categorize the 15 items of HCV-related knowledge into three domains: route of HCV transmission, HCV course and complications, and HCV treatment. RESULTS: The prevalence of UoHCV was 58.7%-62.6% and 15.1%-31.3% in the HCV-seronegative and HCV-seropositive groups, respectively, across 3 periods. More participants with UoHCV believed that HCV infection was only contracted by intravenous injection. In the HCV-seropositive group, participants with UoHCV were more likely to have HIV diagnosis before 2008 (vs. 2014-2020), be men who have sex with men (vs. people who inject drugs), and have hepatitis A virus seronegativity. In the HCV-seronegative group, participants with UoHCV were more likely to have a recent history of sexually transmitted diseases, but had a lower education level, had received less information on HCV infection from clinicians, and were less likely to have heard of HCV infection prior to the research. UoHCV was associated with lower scores for three domains of HCV-related knowledge in both groups. CONCLUSIONS: The negative association of UoHCV with HCV-related knowledge suggests that strategies targeting patients according to their HCV serostatus should be implemented to reduce UoHCV and eradicate HCV infection among HIV-positive patients.

Insight into the rapid sodium storage mechanism of the fiber-like oxygen-doped hierarchical porous biomass derived hard carbon.

Biomass, as a continuously available raw material, is widely used to produce hard carbon. However, many researchers have ignored the natural special morphology of biomass and the influence of oxygen on the sodium storage performance. Here, we use the cilia of the setaria viridis as the precursor to obtain a fiber-like oxygen-doped hierarchical porous hard carbon (SVC). The sodium storage mechanism of SVC is studied by controlling the pyrolysis temperature. Studies have shown that the natural fibrous structure and vertical holes of SVC can provide channels for the rapid penetration of electrolyte. The appropriate nanocrystal size affords commodious circumstances for the insertion of Na+. More importantly, the increase in carbonization temperature will change the bonding mode of carbon and oxygen, promote the rupture of single bonds and retain the existence of double bonds, which is beneficial to the improvement of coulombic efficiency and reversible capacity. The hybrid sodium storage mechanism composed of insertion behavior and capacitance behavior promotes SVC to have higher reversible capacity (285.4 mAh g-1 at 0.05 A g-1) and excellent rate performance (90.7 mAh g-1 at 5 A g-1). This research provides some new ideas for the study of hard carbon.