Effects of the Interception of Litterfall by the Understory on Carbon Cycling in Eucalyptus Plantations of South China

For the purposes of forest restoration, carbon (C) fixation, and economic improvement, eucalyptus (Eucalyptus urophylla) has been widely planted in South China. The understory of eucalyptus plantations is often occupied by a dense community of the fern Dicranopteris dichotoma, which intercepts tree canopy leaf litter before it reaches the ground. To understand the effects of this interception of litterfall on C cycling in eucalyptus plantations, we quantified the mass of intercepted litter and the influences of litterfall interception on litter decomposition and soil respiration. The total mass of E. urophylla litterfall collected on the understory was similar to that collected by the traditional litter trap method. All of the eucalyptus litterfall is intercepted by the D. dichotoma canopy. Of the litterfall that was intercepted by D. dichotoma, 20–40% and 60–80% was intercepted by the top (50–100 cm) and bottom (0–50 cm) of the understory canopy, respectively. Intercepted litterfall decomposed faster at the bottom of understory canopy (at the base of the plants) than at the top, and decomposition was slower on the soil surface in the absence of understory than on any location in the understory canopy. Soil respiration was highest when both the understory and litter were present and was lowest when both the understory and litter were absent. These results indicate that litterfall interception changed carbon flow between aboveground and belowground through litter decomposition and soil respiration, which changed carbon cycling in eucalyptus plantations. The effects of the understory on litter decomposition and soil respiration should be considered in ecosystem carbon models

Exploring the therapeutic potential of recombinant human lysozyme: a review on wound management system with antibacterial

Lysozyme, a natural antibacterial enzyme protein, possesses the ability to dissolve the cell walls of Gram-positive bacteria, demonstrating broad-spectrum antibacterial activity. Despite its significant potential in treating wound infections and promoting wound healing, its widespread clinical application has yet to be realized. Current research is primarily focused on carrier-based delivery systems for lysozyme. In this review, we discuss four delivery systems that can be employed for lysozyme in wound healing treatment, specifically hydrogels, nanofilms, electrospun fibrous membranes, and modified-lysozyme composite systems. These systems not only enhance the stability of lysozyme but also enable its controlled and sustained release at wound sites, potentially overcoming some of the challenges associated with its direct application. Lastly, we delve into the perspectives and challenges related to the use of these delivery systems, hoping to spur further research and innovation in this promising field

A study of HIV/AIDS related knowledge, attitude and behaviors among female sex workers in Shanghai China

<p>Abstract</p> <p>Background</p> <p>China is currently facing a rapid and widespread increase in human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). The activities of female sex workers (FSWs) have contributed to the mounting epidemic of HIV/AIDS and other sexually transmitted diseases (STDs). Therefore, this study aimed to assess the HIV/AIDS-related knowledge, attitude and risk behaviors among FSWs operating in Shanghai China.</p> <p>Methods</p> <p>A cross-sectional study was conducted in five districts of Shanghai, including three suburbs and two downtown locales. We adopted a cluster randomized sampling method to obtain ten geographic sites which consisted of one or more communities/villages proximal to a location where FSWs were accessible. A total of 324 FSWs from 109 Xitou Fang, massage parlors and hair salons who explicitly provided sexual services were enrolled in the study. Each participant completed a questionnaire survey and interview aimed to collect information on the individual's knowledge, attitude, and behaviors associated with risk for HIV/AIDs.</p> <p>Results</p> <p>The overall correct answer rate of HIV/AIDS-related knowledge was 60.8%, and the knowledge of FSWs from downtown areas was significantly higher than those from suburban areas (<it>P </it>< 0.05). The percentage of FSWs who reported having experiences in commercial sexual services without the use of condoms was 33.6%. Condom slippage or breakage was reported as having occurred at least once by 51.2% of the FSWs. FSWs from suburban areas were found to more often engage in high-risk behaviors, including oral and anal sex, than those from downtown areas (<it>P </it>< 0.001). Many of the FSWs (65.7%) reported having non-client sexual partners (most were identified as boyfriends or husbands); however, condom usage with these partners were lower (34.3%).</p> <p>Conclusions</p> <p>Based on the findings from our survey, we advise that promotion of HIV/AIDS-related knowledge be targeted towards FSWs in Shanghai, especially those operating in the suburbs. HIV prevention efforts, such as urging constant condom usage with both clients and steady partners, should be sustained and reinforced among the female sex workers population.</p

A multiscale hybrid model for pro-angiogenic calcium signals in a vascular endothelial cell

Cytosolic calcium machinery is one of the principal signaling mechanisms by which endothelial cells (ECs) respond to external stimuli during several biological processes, including vascular progression in both physiological and pathological conditions. Low concentrations of angiogenic factors (such as VEGF) activate in fact complex pathways involving, among others, second messengers arachidonic acid (AA) and nitric oxide (NO), which in turn control the activity of plasma membrane calcium channels. The subsequent increase in the intracellular level of the ion regulates fundamental biophysical properties of ECs (such as elasticity, intrinsic motility, and chemical strength), enhancing their migratory capacity. Previously, a number of continuous models have represented cytosolic calcium dynamics, while EC migration in angiogenesis has been separately approached with discrete, lattice-based techniques. These two components are here integrated and interfaced to provide a multiscale and hybrid Cellular Potts Model (CPM), where the phenomenology of a motile EC is realistically mediated by its calcium-dependent subcellular events. The model, based on a realistic 3-D cell morphology with a nuclear and a cytosolic region, is set with known biochemical and electrophysiological data. In particular, the resulting simulations are able to reproduce and describe the polarization process, typical of stimulated vascular cells, in various experimental conditions.Moreover, by analyzing the mutual interactions between multilevel biochemical and biomechanical aspects, our study investigates ways to inhibit cell migration: such strategies have in fact the potential to result in pharmacological interventions useful to disrupt malignant vascular progressio

The role of RhoA/Rho kinase pathway in endothelial dysfunction

Endothelial dysfunction is a key event in the development of vascular disease, and it precedes clinically obvious vascular pathology. Abnormal activation of the RhoA/Rho kinase (ROCK) pathway has been found to elevate vascular tone through unbalancing the production of vasodilating and vasoconstricting substances. Inhibition of the RhoA/ROCK pathway can prevent endothelial dysfunction in a variety of pathological conditions. This review, based on recent molecular, cellular, and animal studies, focuses on the current understanding of the ROCK pathway and its roles in endothelial dysfunction

Cassava genome from a wild ancestor to cultivated varieties

Cassava is a major tropical food crop in the Euphorbiaceae family that has high carbohydrate production potential and adaptability to diverse environments. Here we present the draft genome sequences of a wild ancestor and a domesticated variety of cassava and comparative analyses with a partial inbred line. We identify 1,584 and 1,678 gene models specific to the wild and domesticated varieties, respectively, and discover high heterozygosity and millions of single-nucleotide variations. Our analyses reveal that genes involved in photosynthesis, starch accumulation and abiotic stresses have been positively selected, whereas those involved in cell wall biosynthesis and secondary metabolism, including cyanogenic glucoside formation, have been negatively selected in the cultivated varieties, reflecting the result of natural selection and domestication. Differences in microRNA genes and retrotransposon regulation could partly explain an increased carbon flux towards starch accumulation and reduced cyanogenic glucoside accumulation in domesticated cassava. These results may contribute to genetic improvement of cassava through better understanding of its biology

TOR kinase complexes and cell migration

Cell migration is a fundamental process in a wide array of biological and pathological responses. It is regulated by complex signal transduction pathways in response to external cues that couple to growth factor and chemokine receptors. In recent years, the target of rapamycin (TOR) kinase, as part of either TOR complex 1 (TORC1) or TOR complex 2 (TORC2), has been shown to be an important signaling component linking external signals to the cytoskeletal machinery in a variety of cell types and organisms. Thus, these complexes have emerged as key regulators of cell migration and chemotaxis