121 research outputs found
Melting -ice into flatland: flat limit of massless scalar scattering
We delineate the flat limit of massless scalar scattering in
. We derive the 1 1 -matrix from the CFT
2-point function, which is proportional to the momentum-conserving delta
function. We unveil a captivating kinematical characteristic of the
massless -matrix in , elucidating the presence of product of
two delta functions arising from the contact interaction within the
realm of the flat limit of AdS/CFT. We also show that the factorization of the
-matrix for integrable models in the flat limit,
employing a focused analysis on contact interaction, which play a pivotal role
as fundamental constituents in the construction of the non-perturbative
-matrix within integrable models. Although the factorization of
the -matrix in integrable models is commonly perceived as an
intrinsically non-perturbative notion, we effectively showcase its
manifestation at the tree level in the flat limit. We calculate the
-matrix by making use of the mapping between the CFT operator on
the AdS boundary, and the scattering state in flat space. We adopt the bulk
operator reconstruction to examine massless scalar scattering in the flat
limit. We solve the Klein-Gordon equation in the global for
the massless scalar field. Notably, the solution is remarkably simple,
characterized by a pure phase in global time and a sinusoidal function in the
radial coordinate. This simplicity extends to the smearing function, enabling a
mapping between the scattering state and CFT operator taking AdS corrections
into account
Brans-Dicke Cosmology: Thermodynamic viability
Brans-Dicke cosmological models for a spatially isotropic and homogeneous
universe are tested in terms of the validity of the Generalized Second Law of
Thermodynamics (GSL). The investigation is carried out in the Einstein frame.
It is found that the models are thermodynamically viable for negative values of
the Brans-Dicke parameter w and thus are quite consistent with the recent
accelerated expansion of the universe.Comment: 8 pages, to appear in EPJ
Signature flip in deceleration parameter: A thermodynamic phase transition?
Using the Hayward-Kodama temperature for the apparent horizon, it is found
that matter content in the Universe is not thermodynamically stable, and the
entry to the late accelerated expansion is actually a second order phase
transition. The cosmological model used for the purpose is one that imitates
the CDM model, the favoured model for the present Universe.Comment: Title has been change
Towards an IR finite S-matrix in the flat limit of AdS/CFT
Asymptotic Fock spaces lead to IR divergences in S-matrices. The issue can be
traced back to the assumption of asymptotic decoupling, and its relaxation
leads to Faddeev-Kulish states and an IR-finite S-matrix. In this paper we
initiate the exploration of these states in the context of the flat limit of
AdS/CFT. We construct asymptotic states as flat limits of fields that interact
with the electro-magnetic field in AdS, and provide a reconstruction in terms
of the dual CFT operators.Comment: 23 pages, 2 figure
Functional and Probiotic Attributes of an Indigenous Isolate of Lactobacillus plantarum
BACKGROUND:Probiotic microorganisms favorably alter the intestinal microflora balance, promote intestinal integrity and mobility, inhibit the growth of harmful bacteria and increase resistance to infection. Probiotics are increasingly used in nutraceuticals, functional foods or in microbial interference treatment. However, the effectiveness of probiotic organism is considered to be population-specific due to variation in gut microflora, food habits and specific host-microbial interactions. Most of the probiotic strains available in the market are of western or European origin, and a strong need for exploring new indigenous probiotic organisms is felt. METHODS AND FINDINGS:An indigenous isolate Lp9 identified as Lactobacillus plantarum by molecular-typing methods was studied extensively for its functional and probiotic attributes, viz., acid and bile salt tolerance, cell surface hydrophobicity, autoaggregation and Caco-2 cell-binding as well as antibacterial and antioxidative activities. Lp9 isolate could survive 2 h incubation at pH 1.5-2.0 and toxicity of 1.5-2.0% oxgall bile. Lp9 could deconjugate major bile salts like glycocholate and deoxytaurocholate, indicating its potential to cause hypocholesterolemia. The isolate exhibited cell-surface hydrophobicity of approximately 37% and autoaggregation of approximately 31%. Presence of putative probiotic marker genes like mucus-binding protein (mub), fibronectin-binding protein (fbp) and bile salt hydrolase (bsh) were confirmed by PCR. Presence of these genes suggested the possibility of specific interaction and colonization potential of Lp9 isolate in the gut, which was also suggested by a good adhesion ratio of 7.4+/-1.3% with Caco-2 cell line. The isolate demonstrated higher free radical scavenging activity than standard probiotics L. johnsonii LA1 and L. acidophilus LA7. Lp9 also exhibited antibacterial activity against E. coli, L. monocytogenes, S. typhi, S. aureus and B. cereus. CONCLUSION:The indigenous Lactobacillus plantarum Lp9 exhibited high resistance against low pH and bile and possessed antibacterial, antioxidative and cholesterol lowering properties with a potential for exploitation in the development of indigenous functional food or nutraceuticals
Green Chemo-Prevention: An Integrated Review Between Agriculture and Medicine
The isothiocyanate's chemoprevention properties are reported to be present in cruciferous veggies through a variety of mechanisms. Sulforaphane, a phytochemical found in green leafy vegetables, has shown promise in the prevention and treatment of several cancers, including those of the prostate, breast, colon, skin, urinary bladder, and oral cavities. These malignancies include those that affect these organs. This substance is naturally present in broccoli sprouts, kale, cabbage, cauliflower, and garden cress. Broccoli should be a regular part of your diet because it contains a variety of bioactive substances such as vitamins, polyphenols, sulfides, glucosinolates, and antioxidants. Sulforaphane may be used as an inexpensive replacement or dietary supplement for chemo preventive therapy, according to the findings of epidemiological and experimental studies.
Phase 2 detoxification enzymes like glutathione transferases, epoxide hydrolase, NAD(P)H: quinone reductase, and glucuronosyltransferases, as well as epoxide hydrolase and epoxide hydrolase, are produced when the body is stimulated. This is a useful tactic for preventing cancer and fending off the harm that electrophiles and reactive oxygen species can cause. Isothiocyanates are widely distributed in the Cruciferae family and Brassica genus of food plants, which include both broccoli and cauliflower. The most typical form of these substances is glucosinolate precursors. Sulforaphane and 4-methylsulfinylbutyl isothiocyanate, two of these isothiocyanates, are particularly powerful inducers of phase 2 enzymes.
It is feasible to successfully extract glucosinolates and isothiocyanates from plants by homogenizing them at a temperature of around 50 degrees Celsius in a solution of equal parts dimethyl sulfoxide, dimethylformamide, and acetonitrile. This method avoids the hydrolysis of glucosinolates by myrosinase.
It's interesting to note that glucoraphanin, the precursor to sulforaphane, is 10–100 times more abundant in 3-day-old sprouts of various cruciferous vegetables, including broccoli and cauliflower than it is in fully grown veggies. Dimethylbenz(a)anthracene-treated rats displayed notable reductions in mammary tumor occurrence, quantity, and rate of growth when fed extracts from 3-day-old broccoli sprouts. These extracts' primary enzyme-inducing components were either glucoraphanin or sulforaphane. As a result, crucifer sprouts might provide an equivalent amount of cancer prevention to eating far larger quantities of the same mature vegetable species
Inflammatory bowel disease, colorectal cancer and type 2 diabetes mellitus: the links
Abstract
The co-occurrence of the three disease entities, inflammatory bowel disease (IBD),
colorectal cancer (CRC), type 2diabetes mellitus (T2DM) along with inflammation and
dismicrobism has been frequently reported. Some authors have even suggested that
dysbiosis could be the link through a molecular crosstalk of multiple inflammatory loops
including TGFβ, NFKB, TNFα and ROS among others.
This review focuses on the inflammatory process along with the role of microbiota in the
pathophysiology of the three diseases.
The etiology of IBD is multifactorial, and like CRC and T2DM, it is associated with a
widespread and sustained GI inflammation and dismicrobism, whereby an array of proinflammatory
mediators and other related biomolecules are up-regulated, both locally and
systematically. Such a persistent or an inadequately resolved chronic inflammation may be a
causative agent, in the presence other factors, leading to several pathologies such as IBD,
CRC and T2DM.
TGFβ plays a crucial role in pancreatic β cell malfunctioning as glucotoxicity stimulates its
signaling cascade through smad 3, IL-6 and epithelial to mesenchymal transition. Such a
cascade could lead to macrophages and other cells recruitment, inflammation, then IBD and
CRC.
NFkB is also another key regulator in the crosstalk among the pathways leading to the three
disease entities. It plays a major role in linking inflammation to cancer development through
its ability to up regulate several inflammatory and tumor promoting cytokines like: IL-6, IL-1 α
and TNF α, as well as genes like BCL2 and BCLXL. It activates JAK/STAT signaling
network via STAT3 transcription factors and promotes epithelial to mesenchymal transition.
It also increases the risk for T2DM in obese people. In brief, NFKB is a matchmaker
between inflammation, IBD, cancer and diabetes.
In addition, TNFα plays a pivotal role in systemic inflammation. It is increased in the mucosa
of IBD patients and has a central role in its pathogenesis. It also activates other signaling
pathways like NFKB and MAPK leading to CRC. It is also overexpressed in the adipose
tissues of obese patients thus linking it to T2DM, chronic inflammation and consequently
CRC.On the other hand, increasing evidence suggests that dysbiosis plays a role in initiating,
maintaining and determining the severity of IBD. Actually, among its functions, it modulates
genotoxic metabolites which are able to induce CRC, a fact proven to be sustained by stool
transfer from patients with CRC. Probiotics, however, may actively prevent CRC as well as
IBD and results in a significant decrease in fasting glycemia in T2DM patients.
In conclusion, IBD, CRC and T2DM are commonly occurring interrelated clinical problems
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In vitro study on the cell adhesion ability of immobilized lactobacilli on natural supports
The aim of the present study was to investigate the effect of probiotic immobilization onto wheat grains, both wet and freeze dried, on the adhesion properties of the probiotic cells and make comparisons with wet and freeze dried free cells. Lactobacillus casei ATCC 393 and Lactobacillus plantarum NCIMB 8826 were used as model probiotic strains. The results showed satisfactory adhesion ability of free cells to a monolayer of Caco-2 cells (> 1000 CFU/100 Caco-2 cells for wet cells). Cell immobilization resulted in a significant decrease in adhesion, for both wet and freeze dried formulations, most likely because immobilized cells did not have direct access to the Caco-2 cells, but it still remained in adequate levels (> 100 CFU/100 Caco-2 cells for wet cells). No clear correlation could be observed between cell adhesion and the hydrophobicity of the bacterial cells, measured by the hexadecane adhesion assay. Most notably, immobilization enhanced the monolayer integrity of Caco-2 cells, demonstrated by a more than 2-fold increase in transepithelial electrical resistance (TEER) compared to free cells. SEM micrographs ascertained the adhesion of both immobilized and free cells to the brush border microvilli. Finally, the impact of the food matrix on the adhesion properties of probiotic bacteria and on the design of novel functional products is discussed
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