Molecular insights into the anti-inflammatory activity of fermented pineapple juice using multimodal computational studies

Pineapple has been recognized for its potential to enhance health and well-being. This study aimed to gain molecular insights into the anti-inflammatory properties of fermented pineapple juice using multimodal computational studies. In this study, pineapple juice was fermented using Lactobacillus paracasei, and the solution underwent liquid chromatography-mass spectrometry analysis. Network pharmacology was applied to investigate compound interactions and targets. In silico methods assessed compound bioactivities. Protein-protein interactions, network topology, and enrichment analysis identified key compounds. Molecular docking explored compound-receptor interactions in inflammation regulation. Molecular dynamics simulations were conducted to confirm the stability of interactions between the identified crucial compounds and their respective receptors. The study revealed several compounds including short-chain fatty acids, peptides, dihydroxyeicosatrienoic acids, and glycerides that exhibited promising anti-inflammatory properties. Leucyl-leucyl-norleucine and Leu-Leu-Tyr exhibited robust and stable interactions with mitogen-activated protein kinase 14 and IκB kinase β, respectively, indicating their potential as promising therapeutic agents for inflammation modulation. This proposition is grounded in the pivotal involvement of these two proteins in inflammatory signaling pathways. These findings provide valuable insights into the anti-inflammatory potential of these compounds, serving as a foundation for further experimental validation and exploration. Future studies can build upon these results to advance the development of these compounds as effective anti-inflammatory agents.

Monkeypox outbreak 2022: What we know so far and its potential drug targets and management strategies

Monkeypox is a rare zoonotic disease caused by infection with the monkeypox virus. The disease can result in flu-like symptoms, fever, and a persistent rash. The disease is currently spreading throughout the world and prevention and treatment efforts are being intensified. Although there is no treatment that has been specifically approved for monkeypox virus infection, infected patients may benefit from using certain antiviral medications that are typically prescribed for the treatment of smallpox. The drugs are tecovirimat, brincidofovir, and cidofovir, all of which are currently in short supply due to the spread of the monkeypox virus. Resistance is also a concern, as widespread replication of the monkeypox virus can lead to mutations that produce monkeypox viruses that are resistant to the currently available treatments. This article discusses monkeypox disease, potential drug targets, and management strategies to overcome monkeypox disease. With the discovery of new drugs, it is hoped that the problem of insufficient drugs will be resolved, and it is not anticipated that drug resistance will become a major issue in the near future.

Phytochemical Compound Screening to Identify Novel Small Molecules against Dengue Virus: A Docking and Dynamics Study

The spread of the Dengue virus over the world, as well as multiple outbreaks of different serotypes, has resulted in a large number of deaths and a medical emergency, as no viable medications to treat Dengue virus patients have yet been found. In this paper, we provide an in silico virtual screening and molecular dynamics-based analysis to uncover efficient Dengue infection inhibitors. Based on a Google search and literature mining, a large phytochemical library was generated and employed as ligand molecules. In this investigation, the protein target NS2B/NS3 from Dengue was employed, and around 27 compounds were evaluated in a docking study. Phellodendroside (−63 kcal/mole), quercimeritrin (−59.5 kcal/mole), and quercetin-7-O-rutinoside (−54.1 kcal/mole) were chosen based on their binding free energy in MM-GBSA. The tested compounds generated numerous interactions at Lys74, Asn152, and Gln167 residues in the active regions of NS2B/NS3, which is needed for the protein’s inhibition. As a result, the stable mode of docked complexes is defined by various descriptors from molecular dynamics simulations, such as RMSD, SASA, Rg, RMSF, and hydrogen bond. The pharmacological properties of the compounds were also investigated, and no toxicity was found in computational ADMET properties calculations. As a result, this computational analysis may aid fellow researchers in developing innovative Dengue virus inhibitors.

Fruit Bromelain-Derived Peptide Potentially Restrains the Attachment of SARS-CoV-2 Variants to hACE2: A Pharmacoinformatics Approach

Before entering the cell, the SARS-CoV-2 spike glycoprotein receptor-binding domain (RBD) binds to the human angiotensin-converting enzyme 2 (hACE2) receptor. Hence, this RBD is a critical target for the development of antiviral agents. Recent studies have discovered that SARS-CoV-2 variants with mutations in the RBD have spread globally. The purpose of this in silico study was to determine the potential of a fruit bromelain-derived peptide. DYGAVNEVK. to inhibit the entry of various SARS-CoV-2 variants into human cells by targeting the hACE binding site within the RBD. Molecular docking analysis revealed that DYGAVNEVK interacts with several critical RBD binding residues responsible for the adhesion of the RBD to hACE2. Moreover, 100 ns MD simulations revealed stable interactions between DYGAVNEVK and RBD variants derived from the trajectory of root-mean-square deviation (RMSD), radius of gyration (Rg), and root-mean-square fluctuation (RMSF) analysis, as well as free binding energy calculations. Overall, our computational results indicate that DYGAVNEVK warrants further investigation as a candidate for preventing SARS-CoV-2 due to its interaction with the RBD of SARS-CoV-2 variants.

Sequencing batch reactor technology for landfill leachate treatment: A state-of-the-art review

Landfill has become an underlying source of surface and groundwater pollution if not efficiently managed, due to the risk of leachate infiltration into to land and aquifers. The generated leachate is considered a serious environmental threat for the public health, because of the toxic and recalcitrant nature of its constituents. Thus, it must be collected and appropriately treated before being discharged into the environment. At present, there is no single unit process available for proper leachate treatment as conventional wastewater treatment processes cannot achieve a satisfactory level for degrading toxic substances present. Therefore, there is a growing interest in examination of different leachate treatment processes for maximum operational flexibility. Based on leachate characteristics, discharge requirements, technical possibilities, regulatory requirements and financial considerations, several techniques have been applied for its degradation, presenting varying degrees of efficiency. Therefore, this article presents a comprehensive review of existing research articles on the pros and cons of various leachate degradation methods. In line with environmental sustainability, the article stressed on the application and efficiency of sequencing batch reactor (SBR) system treating landfill leachate due to its operational flexibility, resistance to shock loads and high biomass retention. Contributions of integrated leachate treatment technologies with SBR were also discussed. The article further analyzed the effect of different adopted materials, processes, strategies and configurations on leachate treatment. Environmental and operational parameters that affect SBR system were critically discussed. It is believed that information contained in this review will increase readers fundamental knowledge, guide future researchers and be incorporated into future works on experimentally-based SBR studies for leachate treatment.

Dielectric Study of Gel Polymer Electrolyte Based on PVA-K2CO3-SiO2

In this study, effect of filler (SiO2) on dielectric and electrical properties of gel polymer electrolyte (GPE) based on PVA-K2CO3 has been investigated and reported. The electrolyte were prepared by incorporating silica particle as a filler into the un-plasticized electrolyte (PVA-K2CO3). The prepared electrolyte were characterized physicochemically (FTIR) and electrochemically based on electrochemical impedance spectroscopy (EIS). Based on the impedance spectroscopy, complex permittivity (ε*) (dielectric constant and loss) and complex electrical modulus (M*) (real and imaginary modulus) were calculated. Characterization result indicate that SiO2 particles has successfully interacts with PVA-K2CO3 in the form of a three dimensional polymeric network. At low frequencies, high values of complex permittivity (dielectric constant and dielectric loss) were observed, which increased with increasing temperature, signifying an increase in ionic conductivity of the electrolyte. With the incorporation of filler, the peaks of both ε* and M* shifts towards higher frequency side suggesting the speed up the relaxation time. From the electrical modulus, the developed electrolyte is shown to be highly capacitive in nature. Based on the peak shape of the imaginary part of electric modulus, the non-Debye type relaxation predicted. Analysis of both dielectric permittivity and electrical modulus suggest that ionic and polymer segmental motions are strongly coupled. An optimum ionic conductivity of 3.25 × 104 mScm1 was achieved at ambient temperature at a composition of 15 wt.% SiO2 (PKS15).

Personal values, subjective well-being and destination-loyalty intention of international students

What are the factors that predict international students’ destination-loyalty intention? This is the main question this paper addresses, using an online survey among 396 (short-term, N = 182) and (long-term, N = 214) international students at a Norwegian university. Structural equation model-AMOS was conducted to examine relationships among personal values, subjective well-being and destination-loyalty intentions. The results showed that: (1) universalism was positively related to subjective well-being for short-term students; and (2) subjective well-being was positively related to destination-loyalty intention for all groups. We found that relatively stable and happy individuals might be important for ensuring destination-loyalty intentions. Results also indicated that personal values that emphasize justice and equity are also important for short-term international students’ well-being.

Kallikrein-kininogen system activation and bradykinin (B2) receptors in indomethacin induced enterocolitis in genetically susceptible Lewis rats

BACKGROUND

The plasma kallikrein-kinin (K-K) system is activated in acute and chronic relapsing intestinal inflammation induced in Lewis rats by intramural injection of exogenous bacterial components.

AIMS

To determine whether this effect is model specific, K-K system activation was investigated in a modified indomethacin induced enterocolitis model, as well as bradykinin 2 (B2) receptor distribution in the normal and acutely inflamed intestine.

METHODS

Lewis rats injected with daily sublethal doses of indomethacin for two days developed acute (two days) and chronic (14 days) intestinal inflammation. Plasma prekallikrein (amidolytic), high molecular weight kininogen (HK, coagulant) and cleavage of HK (western blot) were assayed to detect K-K activation.

RESULTS

Liver and spleen weights were significantly higher, and body weights and haematocrit values were significantly lower in the indomethacin group than in the control group. During both acute and chronic phases, rats displayed K-K system activation manifested by a significant decrease in plasma prekallikrein and HK functional levels, and by HK cleavage. Plasma T kininogen (a major acute phase protein) was significantly elevated. B2 receptors were identified in both normal and inflammatory intestine with more prominent specific immunohistochemical staining in the acutely inflamed tissue.

CONCLUSIONS

K-K system activation occurs in association with both acute and chronic phases of intestinal injury, regardless of the triggering agent, suggesting that activation of this system is integrally involved in intestinal inflammation in genetically susceptible hosts. Localisation of B2 receptors across intestinal layers provides a structural basis for the kinin function in the intestine.

Specific inhibition of plasma kallikrein modulates chronic granulomatous intestinal and systemic inflammation in genetically susceptible rats

The kallikrein-kinin (K-K) (contact) system is activated during acute and chronic relapsing phases of enterocolitis induced in genetically susceptible Lewis rats by intramural injection of peptidoglycan-polysaccharide (PG-APS). Using the selective plasma kallikrein inhibitor P8720, we investigate whether activation of the K-K system plays a primary role in chronic granulomatous intestinal and systemic inflammation in this model. Group I (negative control) received human serum albumin intramurally. Group II (treatment) received PG-APS intramurally and P8720 orally. Group III (positive control) received PG-APS intramurally and albumin orally. P8720 attenuated the consumption of the contact proteins, high molecular weight kininogen (P<0.03), and factor XI (P<0.04) in group II vs. group III. P8720 decreased chronic intestinal inflammation measured by blinded gross (P<0.01) and histologic (P<0.0005) scores as well as systemic complications (arthritis, splenomegaly, hepatomegaly, leukocytosis, and acute-phase reaction) (P<0.01) in group II as compared with group III. We conclude that relapsing chronic enterocolitis and systemic complications are in part due to plasma K-K system activation, and that inhibition of this pathway is a potential therapeutic approach to human inflammatory bowel disease and associated extraintestinal manifestations.

Activation of the kallikrein-kinin system in arthritis and enterocolitis in genetically susceptible rats: modulation by a selective plasma kallikrein inhibitor

We have developed models of acute and chronic inflammatory arthritis and enterocolitis using peptidoglycan-polysaccharide injected intraperitoneally or subserosally (intramurally) into the distal ileum and cecum. Acute inflammation occurs in both Buffalo and Lewis rats, characterized by inflammation of the injected areas of the intestine. However, only the genetically susceptible Lewis rat develops chronic synovitis and joint erosion or adhesions and granulomatous enterocolitis. In the Lewis rat but not the Buffalo rat, these changes are accompanied by a decrease in plasma prekallikrein and high-molecular-weight kininogen, reflecting activation of the kallikrein-kinin system. Pretreatment with a specific plasma kallikrein inhibitor modulates the acute and chronic arthritis. The same inhibitor partially abrogates the acute changes characteristic of enterocolitis, and preliminary data suggest similar results in the chronic model. The results of these studies indicate that the kallikrein-kinin system plays an important role in arthritis and enterocolitis induced by bacterial products and that kallikrein inhibitors are potential therapeutic agents for inflammatory arthritis and inflammatory bowel disease.

Selective kallikrein-kinin system activation in inbred rats differentially susceptible to granulomatous enterocolitis

BACKGROUND & AIMS

Crohn's disease is characterized by unrestrained inflammation with a genetic component. Genetic susceptibility and activation of the kalli-krein-kinin (contact) system were investigated in experimental enterocolitis and extraintestinal inflammation induced by bacterial polymers.

METHODS

Kinetics of inflammation in inbred Lewis and Buffalo rats injected subserosally with peptidoglycan-polysaccharide polymers were correlated with in vivo and in vitro activation of the contact system.

RESULTS

Lewis rats had a biphasic course of enterocolitis. Acute inflammation peaked 1 day after injection, gradually decreasing until day 14 when intestinal inflammation spontaneously reactivated and persisted for 16 weeks, accompanied by arthritis, granulomatous hepatitis, anemia, and leukocytosis. Self-limited acute enterocolitis in Buffalo rats resolved by 24 days without extraintestinal involvement. Consumption of the precursor proteins prekalli-krein and high-molecular-weight kininogen indicated activation of the plasma contact system in Lewis rats and closely correlated with chronic intestinal inflammation. Contact system activation did not occur in Buffalo rats, even during acute inflammation. In vitro studies showed a decreased rate of kininogen cleavage in Buffalo plasma.

CONCLUSIONS

Selective in vivo and in vitro activation of the contact system in susceptible Lewis rats suggests that this pathway is one determinant of genetic susceptibility to granulomatous enterocolitis and systemic complications.

Cryptosporidium in Khartoum, Sudan

Diarrhoea caused by the protozoan parasite Cryptosporidium has been shown in several tropical countries to be an important health problem, particularly in children. Although infection is often associated with contact with animals, it may also occur through person to person transmission and via contaminated water or food. We have undertaken a cross sectional study to determine the prevalence of Cryptosporidium in children with diarrhoea and in their family contacts, and also investigated its occurrence in adult food handlers. Sixteen of 100 children with diarrhoea and none of the controls, were positive for Cryptosporidium. In addition, seven children had one or more sibs with diarrhoea who also excreted Cryptosporidium. None of the food handlers or asymptomatic children were positive. The results confirm earlier findings that Cryptosporidium is an important cause of diarrhoea in children in Sudan, and suggest that intrafamilial spread occurs.

Contiguous binding and inhibitory sites on kininogens required for the inhibition of platelet calpain

Both high molecular weight kininogen (HK) and low molecular weight kininogens (LK) are potent tight binding inhibitors of platelet calpain (Ki = 2 nM), but the molecular basis for the inhibitory function is not well delineated. The amino acid sequences of the calpain inhibitory domain 2 from human and rat HK were compared for homology with the noninhibitory domains from human and rat domain 3 and from domain 2 of rat T-kininogen, and two areas of nonconserved differences were detected. Computer three-dimensional models were constructed on a template built using the x-ray crystallographic data for cystatin, an evolutionary precursor of HK. Two nonconserved regions in the calpain inhibitory domains flank the highly conserved motif QVVAG to form a continuous surface for interaction with cysteine proteases. Three peptide sequences, components of the modeled surface, were chosen for synthesis from HK D-2: VHPISTQSPDLE (peptide 146-156, NH2-terminal), CTDNAYIDIQLRIASFSQNC (peptide 229-248, COOH-terminal), and CQRQVVAGLNFRIC (185-189, central) containing QVVAG. This last peptide differs from the natural sequence by substitutions of A185C and T195C. Peptides 185-198 and 229-248 were folded by air oxidation of their cysteine residues and then tested for their ability to inhibit calpain and papain. The folded peptide 229-248 inhibited calpain with an IC50 35 microM and unfolding reduced this effect. The folded peptide 185-198 did not inhibit calpain, but when preincubated with calpain, could block the inhibition by HK indicating a probable enzyme binding site. Peptide 146-157 did not inhibit calpain but could inhibit papain with an IC50 of 20 microM. We have thus defined separate binding and inhibitory sequences on HK which form a contiguous surface for thiol protease interactions.

Total intravenous anesthesia with etomidate, alfentanil and droperidol

Forty-six women admitted for gynecologic surgery, were given alfentanil 1 mg, droperidol 2.5 mg and etomidate 0.3 mg/kg body weight intravenously for induction. Anesthesia was maintained using etomidate infused at a rate of 0.1 mg/kg/min for 5 minutes and at 0.01 mg/kg/min afterwards. Analgesia was achieved with a bolus injection of alfentanil prior to surgery, supplemented with additional injections of alfentanil as needed. Controlled ventilation was done with a mixture of air/oxygen. Anesthesia was uneventful in all but two patients. Blood pressure and heart rate remained stable during the entire operative period. Recovery from anesthesia was smooth, although the combination with etomidate and droperidol appears to prolong the recovery time.