Narrow Results

Recently, boolean hierarchies over NP and over RP (denoted BH and RBH respectively) have been introduced in complexity theory. They have proved particularly useful in carefully classifying natural problems which are not finely classified using more standard time and space complexity classes. In this paper we are particularly interested in the structural properties of these hierarchies and in relationships among various boolean hierarchies.

Establishing the most significant relationships between BH, RBH, and other complexity classes would imply solving some of the major open problems in complexity theory. To date the only significant relations known are: , and RBH⊆BH. Essentially nothing is known about the fine structure of BH or of RBH.

In [5] an oracle X is constructed for which both BH^x and RBH^x have an infinite number of proper levels. Further each level of RBH is properly contained in the corresponding level of BH, and RBH is properly contained in PP. In this paper we further explore these constructions. We prove that some of these separations are “strong” separations. That is, they can be witnessed by sets that cannot be “approximated” by sets in the smaller class: the separating sets are immune to sets from the smaller class.

Specifically, we prove that the separations between RBH, BPP, PP and each level of BH, can be witnessed by immune sets.

This paper describes an evolutionary model based on sexual Penna model and shape space model with infection and immunity. Each individual is represented by Penna model with an immune system. In order to study how the infection and immunity influence the survival process, we modify the Verhulst factor. Then, we present the results of our simulations, and discuss the evolution of population and the effect of immunity respectively. In addition, we study the effect of the memory of the immune system and the effect of vaccination under different conditions.

We have modified the Penna standard sexual model in such a way, that the state of each individual has been determined by the individual fluctuation and the fluctuation of the environment. If the sum of both fluctuations is higher than the assumed limit, the organism dies. Additionally, the individuals can learn the trends of the environment's fluctuations, diminishing their deleterious effects. This mechanism leads to the higher mortality of the youngest individuals and the lowest mortality of individuals just before reaching the minimum reproduction age. These phenomena are observed in any mortality curve describing the age structures of human populations.

Pinus massoniana bark extract (PMBE) is a mixture of flavonoids, and showed a capability of inducing cell apoptosis; however, its properties have not yet been fully investigated. This paper evaluates the antitumor effects of PMBE in murine sarcoma S180 both in vitro and in vivo. In vitro, the growth inhibition of S180 cells was concentration dependent on PMBE as shown by the CCK-8 assay. The AO/EB staining and flow cytometry assay showed that PMBE induced S180 cell apoptosis. Cell cycle analysis revealed that the cells in the S phase were decreased by treatment with PMBE. In vivo, the treatment of 100, 200, and 300 mg/kg PMBE reduced the tumor weight and volume of S180-bearing NIH mice by 9%–67% and 13%–68%, respectively. Peripheral leukocyte count and lymphoproliferation were increased significantly after treatment with PMBE. Our results suggest that PMBE inhibits the tumor cell growth by inducing cell apoptosis and improving lymphoproliferation.

The objective of this review was to summarize and critically evaluate the clinical evidence of the effect of qigong exercise on immunity and its efficacy in the prevention or treatment of infectious diseases. Thirteen databases were searched from their respective inceptions through January 2011, and all controlled clinical trials of qigong exercise on immunity and infections were included. Quality and validity of the included studies were evaluated using standard scales. Seven studies including two randomized controlled trials (RCTs), two controlled clinical trials (CCTs) and three retrospective observational studies (ROSs) met the inclusion criteria. One study focused on functional measures of immunity (antigen-induced immunity) and six studies on enumerative parameters of immunity. No study on clinical symptoms relevant to infectious diseases could be identified. Overall, the included studies suggested favorable effects of qigong exercise on immunity, but the quality of research for most of the studies examined in this review was poor. Further rigorously designed studies are required, which should adhere to accepted standards of methodology for clinical trials.

Analytical models of tumor growth in the presence and absence of drug is important for studying the dynamics of treatment in oncology. In this paper, a time-variant state-space model is investigated. The model captures the inherent nonlinearity of the system. Physiological constraints of the system are considered in the model and controllability of the tumor load is examined. If it is possible to find a sequence of drug doses that can drive the tumor load to any arbitrary negligibly small final condition from any arbitrary initial condition in a given number of days without affecting the physiological state of the patient, the tumor is said to be controllable. Drug administration strategies like maximum tolerated dose, metronomic chemotherapy in the presence and absence of immunotherapy have been examined. It is found that low yet prolonged continuous dosing of drug along with tuning of biological factors may be a better workable strategy for positive treatment outcome.

Analytical modeling and computer simulation may provide an assessment for the success of different cancer therapeutic strategies (both maximum tolerable dosing and metronomic dosing), particularly for the presence of microscopically dormant cells. Different authors substantially showed that metronomic strategy is better than maximum tolerable dosing. In the present work, the different physiological constraints have been considered. Accumulation of drug, dead tumor cells as well as metabolites produced by living tumor cells produce toxicity that affect the physiological system. This affects the subsequent drug application and thereby the therapeutic procedure and its outcome. Translating these into logistics and incorporating them into analytical state-space models, the transformation of the overall system has been examined through computer simulations. The observation is that situations of frequent drug stoppages may occur due to patho-physiological constraints, which may in turn inactivate the cell-mediated immune response. Simulation results suggest that even the combination of different strategies does not improve the situation. Other ways of boosting the immunity and tuning of biological constraints would be required to get positive outcome.

A deterministic nonlinear mathematical model is developed for typhoid transmission dynamics in human hosts, coupled with multiple transmission routes. The model aims to examine the role of control interventions such as vaccination, environmental sanitation, and saturated treatment on the prevalence of typhoid. First, the qualitative analysis of the model with constant control interventions is performed. The model exhibits a backward bifurcation phenomenon. Sensitivity analysis is also conducted to identify impactful parameters for effective control of the disease. Then, the model is extended to a corresponding optimal control problem to investigate the optimum intervention strategies by assessing their effects on typhoid prevalence and economic load. The characterization of the optimal controls is determined using Pontryagin’s Maximum Principle, and the optimality system is developed. Numerical results suggest that, in the absence of treatment, the combination of vaccination and environmental sanitation controls plays an important role in reducing the typhoid burden and economic load. Moreover, the comprehensive use of the three control interventions is more effective than using any single or two combined control interventions. It reduces the number of infective humans and environmental bacteria as well as the cost burden associated with applied controls and opportunity loss. Thus, the comprehensive effect of the three control interventions is found to be more economical during typhoid outbreaks.

A stochastic model is proposed to analyse the role of immunity processes in modulating the infection by macroparasites, with applications in schistosomiasis.

In order to understand, in terms of the epidemiology of a disease, the consequences of having a population which can recover from the disease back to a state of susceptibility and the additional effects of recovery to immunity, we have formulated and compared a series of models; each includes a biological feature known to occur in a real host-pathogen system. For example, vertical transmission of the disease or free living infective stages of the pathogen. Taken together, these models, in general, follow predictable patterns of behaviour. There are exceptions, but these can be explained in terms of some sort of density dependence or time delay written into the framework of the model.

Herbal Echinacea Root Formulation for Boosting Children’s Immunity.

Taking One for the Girls – Meina Lee tells APBN why boys might want to consider taking the cervical cancer vaccine.

Catching Cancer Early By Dr Achim Plum.

APBN speaks with Dr Axel Ullrich, research director of the Singapore OncoGenome Project at A*STAR's Institute of Medical Biology and director of Molecular Biology at the Max Planck Institute of Biochemistry, who sheds more light on the cancer challenges ahead.

APBN speaks to Professor Soo Khee Chee, director of National Cancer Center, about the much dreaded disease.

APBN chats with Dr Susan Lim, who is widely known in Asia and Singapore for being the first surgeon to have performed a successful liver transplant.

Cancer Research in Asia Pacifc by Serene Ong.

AUSTRALIA – Immune System Boost Cures HIV-like Infections.

AUSTRALIA – Scientists Shed New Light on How Heart Works.

AUSTRALIA – IVF Breakthrough will Increase Chance of Pregnancy.

AUSTRALIA – Study Reveals Possible Secret to Long Life.

AUSTRALIA – Australian Scientists Make Important Discovery for Safer Drugs.

INDIA – Over 40,000 Childhood Cancer Cases in India Every Year.

INDIA – Biotech Sector Set for Booster Dose.

NEW ZEALAND – Laser to Help Predict Foot Ulcers in Diabetics.

PHILIPPINES – Turning School Yards into Vegetable Gardens.

TAIWAN – Key Enterovirus Breakthrough Unveiled.

OTHER REGIONS — New Heart Therapy More Effective in Women.

Delay in GM Food may Cost India.

M&As Set to Rise in India.

Senate Passes America Invents Act.

Oldest Peach Pits Found in China.

Big Gene Bank to Anchor Precision Medicine.

Koning Receives China Food and Drug Administration Clearance.

UC Berkeley, Berkeley Lab Partner with China's Tsinghua on Clean Energy.

China's Temperature, Sea Level Rise Faster than Global Average.

Pandas prefer choosing their own Sex Partners, Researchers find.

How Do Tibetan-Iranian Plateaus Influence the Asian Summer Monsoon?

Pollen Chains Associated with Secondary Pollen Presentation in a Wild Ginger Species.

Researchers Find Structural Isomerism in Gold Nanoparticles.

How Does HCV Escape From Immune Response?

Mt. Qomolangma Glaciers Shrink 28 pct in 40 Years: Report.

DNA Dates Dog Domestication Back 33,000 Years.

Crystal Structures of Human TIM Members: Ebolavirus Entry-enhancing Receptors.

SINGAPORE – A New Way of Looking at Cancer

SINGAPORE – Novel Discovery by NUS Scientists Improves Profiling of AML Patients for Targeted Therapies

SINGAPORE – Red Meat Consumption Linked with Increased Risk of Developing Kidney Failure

SINGAPORE – Thomson Medical and UK-based Cell Therapy Limited Collaborate on Stem Cell Research to Develop Regenerative Medicines

UNITED STATES – New Biomaterial Developed for Injectable Neuronal Control

UNITED STATES – Research Shines Light on Lesser Known Form of Vitamin D in Foods

UNITED STATES – MRIGlobal to Lead International Research Collaboration for Tularemia Vaccine

INDIA – Improving Agricultural Yield and Quality through Tissue Culture Technology

TAIWAN – A Cascade of Protein Aggregation Bombards Mitochondria for Neurodegeneration and Apoptosis under WWOX Deficiency

The following topics are under this section:

• ASIA-PACIFIC — Shedding Light on COVID-19 Vaccine Development
• ASIA-PACIFIC — Community-led Interventions for Improving Blood Pressure Control
• ASIA-PACIFIC — Importance of Redox Homeostasis in Potential Treatment of Disease
• ASIA-PACIFIC — Novel Processor Architecture to Solve Complex Mathematical Problems
• ASIA-PACIFIC — Uncovering Mechanisms of the Human Biological Clock
• ASIA-PACIFIC — Discovery of Healthy Stomach Stem Cells Reveals Cancer Origins
• ASIA-PACIFIC — Cataloguing Cancer “fingerprints” to Map Cancer Genomes
• ASIA-PACIFIC — Creating a Circular Economy using Greenhouse Gases
• REST OF THE WORLD — Guide for Liquid Biopsy in Individual Glioblastoma Patients
• REST OF THE WORLD — Multi-purpose use of Breast and Kidney Cancer Drugs
• REST OF THE WORLD — The Two Faces of Immune Cells
• REST OF THE WORLD — Fine Particle Air Pollution Linked to Development of Kidney Disease

We study a spatially inhomogeneous model of cancer growth based on Michaelis–Menten kinetics, subjected to additive Gaussian noise and multiplicative dichotomous noise. In presence of the latter, we can observe a transition between two stationary states of the system, The transient behaviour generates a spatial pattern of two phases, where cancer cells or immune cells predominate.

Due to their small size, nanoparticles have brought a new era for researchers. They are utilized in different areas, including the food industry, pharmaceuticals, and medicals, for their outstanding properties. Many medicines are also used to treat patients with various diseases. Many researchers are continuing their research to find more applications of these materials. This paper reviews how nanoparticles synthesized from plants can help the immune response. Different nanoparticles have been initially studied with their source of origin, properties, and applications in the immune response. Then, how various nanoparticles work on the immune response has been briefly discussed. Different applications of nanoparticles on immune response with different perceptions have also been considered. The results of the applications of these particles have been debated as well. In the end, these particles’ potential challenges and future opportunities for immune response have been reviewed. This review paper will work as a guide for nanoparticle researchers in immunity.

Microbial pathogens possess a repertoire of virulence determinants that each make unique contributions to fitness during infection. Analysis of these in vivo-expressed functions reveals the biology of the infection process, encompassing the bacterial infection strategies and the host ecological and environmental retaliatory strategies designed to combat them (e.g. thermal, osmotic, oxygen, nutrient and acid stress). Many of the bacterial virulence functions that contribute to a successful infection are normally only expressed during infection. A genetic approach was used to isolate mutants that ectopically expressed many of these functions in a laboratory setting. Lack of DNA adenine methylase (Dam) in Salmonella typhimurium abolishes the preferential expression of many bacterial virulence genes in host tissues. Dam^-Salmonella were proficient in colonization of mucosal sites but were defective in colonization of deeper tissue sites. Additionally, Dam^- mutants were totally avirulent and effective as live vaccines against murine typhoid fever. Since dam is highly conserved in many pathogenic bacteria that cause significant morbidity and mortality worldwide, Dams are potentially excellent targets for both vaccines and antimicrobials.