Allergy Link – Academy of Immunology

Subtalar osteoarthritis (STOA) is often secondary to chronic ankle sprains, which seriously affects the quality of life of patients. Due to its etiology and pathogenesis was not studied equivocally yet, there is currently a lack of effective conservative treatments. Although they have been used for tissue repair, platelet-rich plasma-derived exosomes (PRP-Exo) have the disadvantage of low retention and short-lived therapeutic effects. This study aimed to determine whether incorporation of PRP-Exo in thermosensitive hydrogel (Gel) increased their retention in the joint and thereby playing a therapeutic role on STOA due to chronic mechanical instability established by transecting lateral ligaments (anterior talofibular ligament (ATFL)/calcaneal fibular ligament (CFL)).

PRP-Exo incorporated Gel (Exo-Gel) system, composed of Poloxamer-407 and 188 mixture-based thermoresponsive hydrogel matrix in an optimal ratio, was determined by its release ability of Exo and rheology of Gel response to a different temperature. The biological activity of Exo-Gel was evaluated in vitro, and the therapeutic effect of Exo-Gel on STOA was evaluated in vivo.

Exo released from Exo-Gel continuously for 28 days could promote the proliferation and migration of mouse bone mesenchymal stem cells (mBMSCs) and chondrocytes, at the same time enhance the chondrogenic differentiation of mBMSCs, and inhibit inflammation-induced chondrocyte degeneration. In vivo experiments confirmed that Exo-Gel increased the local retention of Exo, inhibited the apoptosis and hypertrophy of chondrocytes, enhanced their proliferation, and potentially played the role in stem cell recruitment to delay the development of STOA. Thus, Delivery of PRP-Exo incorporated in thermosensitive Gel provides a novel approach of cell-free therapy and has therapeutic effect on STOA.

Aquaporin 4 in Traumatic Brain Injury: From Molecular Pathways to Therapeutic Target

Traumatic brain injury (TBI) is known as an acute degenerative pathology of the central nervous system, and has been shown to increase brain aquaporin 4 (AQP4) expression. Various molecular mechanisms affect AQP4 expression, including neuronal high mobility group box 1, forkhead box O3a, vascular endothelial growth factor, hypoxia-inducible factor-1 α (HIF-1 α) sirtuin 2, NF-κB, Malat1, nerve growth factor and Angiotensin II receptor type 1. In addition, inhibition of AQP4 with FK-506, MK-801 (indirectly by targeting N-methyl-D-aspartate receptor), inactivation of adenosine A2A receptor, levetiracetam, adjudin, progesterone, estrogen, V1aR inhibitor, hypertonic saline, erythropoietin, poloxamer 188, brilliant blue G, HIF-1alpha inhibitor, normobaric oxygen therapy, astaxanthin, epigallocatechin-3-gallate, sesamin, thaliporphine, magnesium, prebiotic fiber, resveratrol and omega-3, as well as AQP4 gene silencing lead to reduced edema upon TBI. This review summarizes current knowledge and evidence on the relationship between AQP4 and TBI, and the potential mechanisms involved.

Solvent-Free Fabrication of Biphasic Lipid-Based Microparticles with Tunable Structure

Lipid-based biphasic microparticles are generally produced by long and complex techniques based on double emulsions. In this study, spray congealing was used as a solvent-free fabrication method with improved processability to transform water-in-oil non-aqueous emulsions into spherical solid lipid-based particles with a biphasic structure (b-MPs).

Emulsions were prepared by melt emulsification using different compositions of lipids (Dynasan®118 and Compritol®888 ATO), surfactants (Cetylstearyl alcohol and Span®60) and hydrophilic carriers (PEGs, Gelucire®48/16 and Poloxamer 188).

First, pseudo-ternary phase diagrams were constructed to identify the area corresponding to each emulsion type (coarse emulsion or microemulsion). The hydrophobicity of the lipid mostly affected the interfacial tension, and thus the microstructure of the emulsion. Emulsions were then processed by spray congealing and the obtained b-MPs were characterized in terms of thermal and chemical properties (by DSC and FT-IR), external and internal morphology (by SEM, CLSM and Raman mapping).

Solid free-flowing spherical particles (main size range 200-355 µm) with different architectures were successfully produced: microemulsions led to the formation of particles with a homogeneous internal structure, while coarse emulsions generated “multicores-shell” particles consisting of variable size hydrophilic cores evenly distributed within the crystalline lipid phase. Depending on their composition and structure, b-MPs could achieve various release profiles, representing a more versatile system than microparticles based on a single lipid phase. The formulation and technological strategy proposed, provides a feasible and cost-effective way of fabricating b-MPs with tunable internal structure and release behavior.

Genome DNA Leakage of Adeno-Associated Virus Under Freeze-Thaw Stress

Adeno-associated virus (AAV) has become an emerging tool for human gene therapies. Currently, AAV gene therapies are subjected to multiple freeze-thaw cycles during manufacturing, storage, transportation, and administration. While studies have shown that multiple freeze-thaw cycles led to a decrease in transduction efficiency, the AAV degradation mechanism during freeze-thaw is not well understood.

Here, we have characterized the impact of freeze-thaw on AAV8 by employing a variety of assays, which revealed significant increases in the amount of free single-stranded DNA (ssDNA) in AAV8 formulations after multiple freeze-thaw cycles. Subsequent analysis using Next Generation Sequencing (NGS) revealed that the ssDNA primarily consisted of genome DNA, indicating that the increased ssDNA leaked out from AAV8.

Experiments performed using different serotypes of AAV confirmed the pervasiveness of such behavior amongst AAVs. In addition, formulation screening studies were performed to understand the impact on genome DNA leakage from AAV. The formulation screening results showed that the addition of 10% sucrose and 0.1% poloxamer 188 to Dulbecco’s phosphate-buffered saline (DPBS) reduced the leakage of ssDNA in AAV samples after freeze-thaw cycles compared to the base formulation of DPBS alone. These findings shed new light on the degradation mechanism of AAVs and stabilization of the AAV-based gene therapies.

Sustained Delivery of Lactoferrin Using Poloxamer Gels for Local Bone Regeneration in a Rat Calvarial Defect Model

Lactoferrin (LF) is a multifunctional milk glycoprotein that promotes bone regeneration. Local delivery of LF at the bone defect site is a promising approach for enhancement of bone regeneration, but efficient systems for sustained local delivery are still largely missing. The aim of this study was to investigate the potential of the poloxamers for sustained delivery of LF to enhance local bone regeneration. The developed LF/poloxamer formulations were liquid at room temperature (20 °C) transforming to a sustained releasing gel depot at body temperature (37 °C). In vitro release studies demonstrated an initial burst release (~50%), followed by slower release of LF for up to 72 h.

Poloxamer 188

from TargetMol Chemicals

T40802-10mg | 10mg: Ask for price

Poloxamer 188

from TargetMol Chemicals

T40802-1g | 1g: Ask for price

Poloxamer 188

from TargetMol Chemicals

T40802-1mg | 1mg: Ask for price

Poloxamer 188

from TargetMol Chemicals

T40802-50mg | 50mg: Ask for price

Poloxamer 188

from TargetMol Chemicals

T40802-5mg | 5mg: Ask for price

100mL Poloxamer 188 - PK6

from Scientific Laboratory Supplies

13-901-CI | PK6: 137.70 EUR

100 G POLOXAMER 188, POWDER

from CORNING

61-161-RM | 100 g/pk: 80.40 EUR

Poloxamer 407

from TargetMol Chemicals

T19524-10mg | 10mg: Ask for price

Poloxamer 407

from TargetMol Chemicals

T19524-1g | 1g: Ask for price

Poloxamer 407

from TargetMol Chemicals

T19524-1mg | 1mg: Ask for price

Poloxamer 407

from TargetMol Chemicals

T19524-50mg | 50mg: Ask for price

Poloxamer 407

from TargetMol Chemicals

T19524-5mg | 5mg: Ask for price

Poloxamer Solid

from Toronto Research Chemicals

P688040 | 100g: 64.00 EUR

Poloxin

from MedKoo Biosciences

406449 | 10.0mg: 250.00 EUR

Poloxin

from ApexBio

A3732-10 | 10 mg: 44.00 EUR

Poloxin

from ApexBio

A3732-5.1 | 10 mM (in 1mL DMSO): 48.00 EUR

Poloxin

from ApexBio

A3732-50 | 50 mg: 176.00 EUR

Poloxin

from TargetMol Chemicals

T16560-10mg | 10mg: Ask for price

Poloxin

from TargetMol Chemicals

T16560-1g | 1g: Ask for price

Poloxamer, with and without LF, increased osteoblast viability at 72 h (p < 0.05) compared to control, and the immune response from THP-1 cells was mild when compared to the suture material. In rat calvarial defects, the LF/poloxamer group had lower bone volume than the controls (p = 0.0435). No difference was observed in tissue mineral density and lower bone defect coverage scores (p = 0.0267) at 12 weeks after surgery. In conclusion, LF/poloxamer formulations support cell viability and do not induce an unfavourable immune response; however, LF delivery via the current formulation of LF200/poloxamer gel did not demonstrate enhanced bone regeneration and was not compatible with the rat calvarial defect model.

Postural Balance Ability and the Effect of Visual Restriction on Older Dancers and Non-Dancers

February 18, 2022 by Jeremy

Dance has been suggested to be an advantageous exercise modality for improving postural balance performance and reducing the risk of falls in the older population. The main purpose of this study was to investigate whether visual restriction impacts older dancers and non-dancers differently during a quiet stance balance performance test.

We hypothesized higher balance performance and greater balance deterioration due to visual restriction in dancers compared with non-dancers, indicating the superior contribution of the visual channel in the expected higher balance performances of dancers. Sixty-nine (38 men, 31 women, 74 ± 6 years) healthy older adults participated and were grouped into a Greek traditional dance group (n = 31, two to three times/week for 1.5 h/session, minimum of 3 years) and a non-dancer control group (n = 38, no systematic exercise history).

The participants completed an assessment of one-legged quiet stance trials using both left and right legs and with eyes open while standing barefoot on a force plate (Wii, A/D converter, 1,000 Hz; Biovision) and two-legged trials with both eyes open and closed. The possible differences in the anthropometric and one-legged balance parameters were examined by a univariate ANOVA with group and sex as fixed factors.

This ANOVA was performed using the same fixed factors and vision as the repeated measures factor for the two-legged balance parameters. In the one-legged task, the dance group showed significantly lower values in anteroposterior and mediolateral sway amplitudes (p = 0.001 and p = 0.035) and path length measured in both directions (p = 0.001) compared with the non-dancers. In the two-legged stance, we found a significant vision effect on path length (p < 0.001) and anteroposterior amplitude (p < 0.001), whereas mediolateral amplitude did not differ significantly (p = 0.439) between closed and open eyes. The dance group had a significantly lower CoP path length (p = 0.006) and anteroposterior (p = 0.001) and mediolateral sway amplitudes (p = 0.003) both in the eyes-open and eyes-closed trials compared with the control group.

The superior balance performance in the two postural tasks found in the dancers is possibly the result of the coordinated, aesthetically oriented intersegmental movements, including alternations between one- and two-legged stance phases, that comes with dance. Visual restriction resulted in a similar deterioration of balance performance in both groups, thus suggesting that the contribution of the visual channel alone cannot explain the superior balance performance of dancers.

Refractive corneal inlay implantation outcomes: a preliminary systematic review

Purpose: To review all case series of refractive corneal inlay implantation: Flexivue (Presbia, Netherlands), Invue (BioVision, Brügg, Switzerland) and Icolens (Neoptics, Hünenberg, Switzerland) performed in presbyopia patients and to evaluate the reported visual outcomes. In addition, our aim is to provide assessment for complications and to report the satisfaction rates.

Methods: PubMed, Web of Science and Scopus databases were consulted using “refractive corneal inlay”, “Flexivue Inlay”, “Invue Inlay” and “Icolens inlay” as keywords. 147 articles were found, and they were assessed considering the inclusion and exclusion criteria. After filtering, this systemic review included ten articles, published between 2011 and 2020.

Results: 308 eyes from 308 participants were enrolled in this systematic review. Mean maximum follow-up was 13.9 months. Nine of the ten case series included used femtosecond laser for the corneal pocket creation. Mean pocket depth was 293.75 µm. 77.5% of the eyes reported a postoperative uncorrected near visual acuity of 20/32 or better, and 19.20% of the inlay-implanted eyes achieved an uncorrected distance visual acuity of 20/20 or better. The most prominent complications were halos, pain, photophobia, and poor distance visual acuity. 27 eyes (8.7%) had to be explanted due to complications, such as near-distance spectacle dependence or blurred distance vision.

Conclusion: Refractive corneal inlay outcomes demonstrated high efficacy, safety, and satisfaction rates. Furthermore, it is a reversible technique. However, the findings must be viewed with caution due potential conflict of interest. Further research with higher sample size is needed to validate these findings.

Keywords: Flexivue inlay; Icolens inlay; Invue inlay; Refractive inlay.

Quantifying Visual Image Quality: A Bayesian View

Image quality assessment (IQA) models aim to establish a quantitative relationship between visual images and their quality as perceived by human observers. IQA modeling plays a special bridging role between vision science and engineering practice, both as a test-bed for vision theories and computational biovision models and as a powerful tool that could potentially have a profound impact on a broad range of image processing, computer vision, and computer graphics applications for design, optimization, and evaluation purposes.

The growth of IQA research has accelerated over the past two decades. In this review, we present an overview of IQA methods from a Bayesian perspective, with the goals of unifying a wide spectrum of IQA approaches under a common framework and providing useful references to fundamental concepts accessible to vision scientists and image processing practitioners.

We discuss the implications of the successes and limitations of modern IQA methods for biological vision and the prospect for vision science to inform the design of future artificial vision systems. (The detailed model taxonomy can be found at http://ivc.uwaterloo.ca/research/bayesianIQA/.) Expected final online publication date for the Annual Review of Vision Science, Volume 7 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Nitric oxide in infertile females in the niger-delta region of Nigeria

Background: Infertility is a public health challenge and it is a distressing personal tragedy for couples, more so for the female partners. Risk factors and causes of infertility vary from region to region. Reactive species is of current interest in the pathogenesis and management of infertility, especially in the Niger-Delta Region of Nigeria where environmental hazards of oil exploration exists.

Aim: The overall goal of this study was to determine and compare the serum reactive species levels (nitric oxide) in fertile and infertile women attending the infertility clinic at the Delta State University Teaching Hospital, Oghara, and Central Hospital, Warri.

Methods: This was a prospective case-control study in which 70 women evaluated for infertility were recruited into the study. A fertile patient matched for age and body mass index (BMI) attending family planning clinic was selected as control. Serum nitric oxide estimation was done using the BioVision Nitric Oxide Colorimetric Assay Kit. Statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS). Student’s t-test was applied to compare the serum levels of nitric acid and the differences were considered significant if P < 0.05.

Biotinylated Bovine Serum Albumin (Biotin-LC-BSA) (3 biotin/BSA)

from Biovision

7097-25 | each: 266.40 EUR

Biotinylated Bovine Serum Albumin (Biotin-LC-BSA) (3 biotin/BSA)

from Biovision

7097-5 | each: 138.00 EUR

Biotinylated Bovine Serum Albumin (Biotin-LC-BSA) (5 biotin/BSA)

from Biovision

7098-25 | each: 279.60 EUR

Biotinylated Bovine Serum Albumin (Biotin-LC-BSA) (5 biotin/BSA)

from Biovision

7098-5 | each: 144.00 EUR

Biotinylated Bovine Serum Albumin (Biotin-LC-BSA) (12 biotin/BSA)

from Biovision

7099-25 | each: 292.80 EUR

Biotinylated Bovine Serum Albumin (Biotin-LC-BSA) (12 biotin/BSA)

from Biovision

7099-5 | each: 157.20 EUR

BIO

from Biovision

1673-1 | each: 189.60 EUR

7BIO

from Biovision

9690-5 | each: 222.00 EUR

7BIO

from Biovision

9690-25 | each: 705.60 EUR

D-(+)-Biotin

from Biovision

9587-10G | each: 418.80 EUR

D-(+)-Biotin

from Biovision

9587-5G | each: 288.00 EUR

Bioymifi

from Biovision

9424-25 | each: 652.80 EUR

Bioymifi

from Biovision

9424-5 | each: 210.00 EUR

Biotin-NHS

from Biovision

2347-1000 | each: 561.60 EUR

Biotin-NHS

from Biovision

2347-250 | each: 326.40 EUR

Biotin-NHS

from Biovision

2347-50 | each: 138.00 EUR

Results: Infertile women had significantly higher mean serum nitric oxide levels than fertile women: 34.33 (SD 5.93) μmol/L versus 18.27 (SD 2.63) μmol/L (P < 0.001). Women with secondary infertility had significantly higher mean levels of nitric oxide than those with primary infertility: 38.13 (SD 3.39) μmol/L versus 22.72 (SD 4.36) μmol/L (P < 0.001).

Conclusion: The study showed that serum nitric oxide level was significantly elevated in women with infertility compared to women of proven fertility. Hence, oxidative stress from reactive species may be a contributory factor to infertility in women in the Niger-Delta Region of Nigeria.

Drugs(1) Identification of the PA1113 Gene Product as an ABC Transporter Involved in the Uptake of Carbenicillin in Pseudomonas aeruginosa PAO1

February 18, 2022 by Jeremy

The resistance of Pseudomonas aeruginosa to antibiotics is multi factorial and complex. Whereas efflux pumps such as MexAB-OprM have been thought to predominate, here we show that a novel ATP Binding Cassette (ABC) transporter that mediates influx of carbenicillin from the periplasm to the cytoplasm and away from its cell wall target plays an important role in the resistance of P. aeruginosa to this antibiotic.

Treatment of P. aeruginosa with verapamil, an inhibitor of ABC transporters in eukaryotic cells, increases its sensitivity to carbenicillin.

Using amino acid sequence homology with known verapamil protein targets as a probe, we determined that the PA1113 gene product, an ABC transporter, mediates carbenicillin uptake into the bacterial cytoplasm.

Docking and pharmacological analyses showed that verapamil and carbenicillin compete for the same site on the PA1113 gene protein, explaining the inhibitory effect of verapamil on carbenicillin uptake, and furthermore suggest that the PA1113 ABC transporter accounts for about 30% of P. aeruginosa carbenicillin resistance.

Our findings demonstrate that the PA1113 gene product helps mediate carbenicillin resistance by transporting it away from its cell wall target and represents a promising new therapeutic target.

MexXY RND pump of Pseudomonas aeruginosa PA7 effluxes bi-anionic β-lactams carbenicillin and sulbenicillin when it partners with the outer membrane factor OprA but not with OprM

Antibiotic resistance in Pseudomonas aeruginosa is a serious concern in healthcare systems. Among the determinants of antibiotic resistance in P. aeruginosa, efflux pumps belonging to the resistance-nodulation-division (RND) family confer resistance to a broad range of antibacterial compounds.

The MexXY efflux system is widely overexpressed in P. aeruginosa isolates from cystic fibrosis (CF) patients. MexXY can form functional complexes with two different outer membrane factors (OMFs), OprA and OprM. In this study, using state-of-the-art genetic tools, the substrate specificities of MexXY-OprA and MexXY-OprM complexes were determined.

Our results show, for the first time, that the substrate profile of the MexXY system from P. aeruginosa PA7 can vary depending on which OM factor (OprM or OprA) it complexes with. While both MexXY-OprA and MexXY-OprM complexes are capable of effluxing aminoglycosides, the bi-anionic β-lactam molecules carbenicillin and sulbenicillin were found to only be the substrate of MexXY-OprA. Our study therefore shows that by partnering with different OMF proteins MexY can expand its substrate profile.

Octenidine/carbenicillin GUMBOS as potential treatment for oropharyngeal gonorrhoea

Background: Reducing Neisseria gonorrhoeae colonies in the oropharynx is a viable solution to minimize the transmission of this bacterium amongst individuals.

Objectives: A strategy involving the electrostatic interaction between a common antiseptic and a discontinued antibiotic (i.e. octenidine and carbenicillin) was evaluated as a potential treatment for gonorrhoea. Octenidine/carbenicillin is a novel group of uniform materials based on organic salts (GUMBOS) with inherent in vitro antibacterial activity that comes from its parent antiseptic and antibacterial ions, octenidine and carbenicillin, respectively.

Methods: Antibacterial activities for octenidine dihydrochloride, disodium carbenicillin, octenidine/carbenicillin and stoichiometrically equivalent 1:1 octenidine dihydrochloride to disodium carbenicillin were assessed using the Kirby-Bauer disc diffusion assay for N. gonorrhoeae (ATCC 49226) and three clinical isolates. Predictive permeability using the Parallel Artificial Membrane Permeability Assay and cytotoxicity against HeLa cells was also evaluated.

Results: Additive in vitro antibacterial activities against N. gonorrhoeae were observed in this study, which suggests octenidine/carbenicillin could be a useful agent in reducing N. gonorrhoeae transmission and minimizing gonorrhoea infections.

Octenidine/carbenicillin also exhibited bioequivalence to azithromycin and doxycycline, two currently prescribed antibiotics. Likewise, octenidine/carbenicillin had improved predicted permeability compared with octenidine dihydrochloride.

Conclusions: Antimicrobial GUMBOS synthesized in this study could be used as an adjunctive treatment approach to current drug therapies for oropharyngeal gonorrhoea infection control and prevention.

SERS investigation and high sensitive detection of carbenicillin disodium drug on the Ag substrate.

The reliable and ultrasensitive detection of antibiotic drug residue is of great interest for environmental protection and human health. Herein, we propose a simple SERS strategy based on Ag nanoparticles (NPs) as substrate with the assistance of aggregation agent (MgSO4) for the SERS investigation and the high sensitive detection of antibiotic drug carbenicillin disodium (CBDM).

The density functional theory calculation was performed for the assignment and identification of Raman bands of the CBDM molecule. The results indicate that the CBDM molecule is close to the Ag NP substrate surface through the carboxyl group. The CBDM molecules on Ag NP substrate exhibit the largest SERS enhancement, when the concentration of MgSO4 is 1 × 10-2 mol/L and the pH value of CBDM solution is 6.

By this SERS method, the limit of detection of CBDM is 0.63 × 10-8 mol/L, which is lower than the standard of European Union for the maximum residue limit of antibiotic drug (1.2 × 10-8 mol/L). And, a quantitative detection method of CBDM can be established. There is a good linear relationship (R2 = 0.9908) in the concentration range of 1.0 × 10-8-1.0 × 10-3 mol/L.

It proves that the proposed SERS method is a simple, rapid (within 6 min), reliable and highly sensitive scheme with a good reproducibility for the detection of CBDM. And, the proposed SERS strategy can also be applied for the high sensitive detection and identification of other antibiotic drug (penicillin).

Mechanisms of RsaL mediated tolerance to ciprofloxacin and carbenicillin in Pseudomonas aeruginosa.

The Pseudomonas aeruginosa RsaL is a negative regulator of the quorum sensing signal synthesis gene lasI. The expression of RsaL is directly activated by the LasI cognate regulator LasR. Thus, RsaL and LasI-LasR (LasI/R) form a regulatory loop.

Further studies revealed that RsaL is a global regulator which controls the expression of numerous genes through quorum sensing system dependent and independent pathways. However, whether RsaL is involved in antibiotic tolerance remains elusive. In this study, we found that the mutation of rsaL increased bacterial tolerance to ciprofloxacin and carbenicillin.

Through motif search, gene expression analyses and electrophoretic mobility shift assays, we found that RsaL directly represses the expression of the narK1K2GHJI operon, which is involved in the tolerance to ciprofloxacin. We further demonstrated that the narK1K2GHJI operon is directly regulated by LasR. In combination, our study revealed a novel operon under the control of the RsaL, LasI/R regulatory loop.

Metal-carbenicillin framework-based nanoantibiotics with enhanced penetration and highly efficient inhibition of MRSA.

The development of effective therapies to control methicillin-resistant Staphylococcus aureus (MRSA) infections is challenging because antibiotics can be degraded by the production of certain enzymes, for example, β-lactamases. Additionally, the antibiotics themselves fail to penetrate the full depth of biofilms formed from extracellular polymers.

Nanoparticle-based carriers can deliver antibiotics with better biofilm penetration, thus combating bacterial resistance. In this study, we describe a general approach for the construction of β-lactam antibiotics and β-lactamase inhibitors co-delivery of nanoantibiotics based on metal-carbenicillin framework-coated mesoporous silica nanoparticles (MSN) to overcome MRSA.

Carbenicillin

from ABM

G054 | 1.0 g: 145.00 EUR

Carbenicillin

from ApexBio

B3412-1000 | 1 g: 93.00 EUR

Carbenicillin

from ApexBio

B3412-250 | 250mg: 73.00 EUR

Carbenicillin

from ApexBio

B3412-5000 | 5 g: 338.00 EUR

CARBENICILLIN

from PhytoTechnology Laboratories

C346 | 100G: 40.12 EUR

Carbenicillin

from MedChemExpress

HY-B0525 | 5g: 308.40 EUR

CARBENICILLIN

from IBI Scientific

IB02010 | 1GM: 40.04 EUR

CARBENICILLIN

from IBI Scientific

IB02020 | 5GM: 98.00 EUR

CARBENICILLIN

from IBI Scientific

IB02025 | 25GM: 119.44 EUR

Carbenicillin

from EWC Diagnostics

MD007-1PK | 1 unit: Ask for price

Carbenicillin 2Na

from Abbexa

abx082066-1g | 1 g: 243.60 EUR

Carbenicillin 2Na

from Abbexa

abx082363-100mg | 100 mg: 226.80 EUR

Carbenicillin 2Na

from Abbexa

abx082534-100mg | 100 mg: 226.80 EUR

Carbenicillin 2Na

from Abbexa

abx082066-100l | 100 µl: 212.50 EUR

Carbenicillin 2Na

from Abbexa

abx082066-1ml | 1 ml: Ask for price

Carbenicillin 2Na

from Abbexa

abx082066-200l | 200 µl: Ask for price

Carbenicillin 2Na

from Abbexa

abx082363-100l | 100 µl: 150.00 EUR

Carbenicillin 2Na

from Abbexa

abx082363-1ml | 1 ml: Ask for price

Carbenicillin 2Na

from Abbexa

abx082363-200l | 200 µl: Ask for price

Carbenicillin 2Na

from Abbexa

abx082534-100l | 100 µl: 162.50 EUR

Carbenicillin 2Na

from Abbexa

abx082534-1ml | 1 ml: Ask for price

Carbenicillin, a β-lactam antibiotic, was used as an organic ligand that coordinates with Fe3+ to form a metal-carbenicillin framework to block the pores of the MSN.

Furthermore, these β-lactamase inhibitor-loaded nanoantibiotics were stable under physiological conditions and could synchronously release antibiotic molecules and inhibitors at the bacterial infection site to achieve a better elimination of antibiotic resistant bacterial strains and biofilms.

We confirmed that these β-lactamase inhibitor-loaded nanoantibiotics had better penetration depth into biofilms and an obvious effect on the inhibition of MRSA both in vitro and in vivo.

Biofunctional Hyaluronic Acid/κ-Carrageenan Injectable Hydrogels for Improved Drug Delivery and Wound Healing

February 18, 2022 by Jeremy

The in situ injectable hydrogel system offers a widespread range of biomedical applications in prompt chronic wound treatment and management, as it provides self-healing, maintains a moist wound microenvironment, and offers good antibacterial properties.

This study aimed to develop and evaluate biopolymer-based thermoreversible injectable hydrogels for effective wound-healing applications and the controlled drug delivery of meropenem. The injectable hydrogel was developed using the solvent casting method and evaluated for structural changes using proton nuclear magnetic resonance, Fourier transforms infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy.

The results indicated the self-assembly of hyaluronic acid and kappa-carrageenan and the thermal stability of the fabricated injectable hydrogel with tunable gelation properties.

The viscosity assessment indicated the in-situ gelling ability and injectability of the hydrogels at various temperatures. The fabricated hydrogel was loaded with meropenem, and the drug release from the hydrogel in phosphate buffer saline (PBS) with a pH of 7.4 was 96.12%, and the simulated wound fluid with a pH of 6.8 was observed to be at 94.73% at 24 h, which corresponds to the sustained delivery of meropenem. Antibacterial studies on P. aeruginosa, S. aureus, and E. coli with meropenem-laden hydrogel showed higher zones of inhibition.

The in vivo studies in Sprague Dawley (SD) rats presented accelerated healing with the drug-loaded injectable hydrogel, while 90% wound closure with the unloaded injectable hydrogel, 70% in the positive control group (SC drug), and 60% in the negative control group was observed (normal saline) after fourteen days. In vivo wound closure analysis confirmed that the developed polymeric hydrogel has synergistic wound-healing potential.

Effect of κ-carrageenan on the gelation properties of oyster protein

Proteins and polysaccharides commonly coexist in the food system, forming complexes and coacervates to make tailor-made food. In this study, the effects of κ-carrageenan on the rheological behavior, network structure, textures, and molecular force of oyster protein (OP treated with high-pressure homogenization were investigated.

Rheological results showed that κ-carrageenan improved the storage modulus of OP, and the higher concentration of κ-carrageenan accelerated the gelation of OP.

The second derivative of infrared spectroscopy revealed that κ-carrageenan contributed to the formation of β-sheet in OP. Molecular force and texture analysis showed that κ-carrageenan might promote the increase of hydrophobic bonds and disulfide bonds, which was helpful to enhance gel strength.

The microstructure showed that the OP gel with 1.5% κ-carrageenan had a compact network structure with abundant minor mesh and sheet edge. This study reveals the gelation mechanism of OP/κ-carrageenan and provides the theoretical basis for developing innovative oyster products.

Efficacy of a carrageenan gel in increasing clearance of anal HPV infections in men: interim analysis of a double-blind randomized controlled trial

Pre-clinical studies demonstrated carrageenan’s anti-human papillomavirus (HPV) activity. We assessed efficacy of a carrageenan-based gel compared to a placebo gel in increasing the clearance of anal HPV infections among gay, bisexual, and other men who have sex with men (gbMSM).

Of 255 enrolled gbMSM, 134 were HPV-positive at baseline and had valid HPV results for ≥2 visits. Carrageenan did not differ from placebo in clearing all baseline infections (HR=0.84, 95% CI: 0.31-2.27), based on having two consecutive HPV-negative visits following at least one HPV-positive. There were no remarkable differences for analyses at the HPV-type level or by HIV status.

Combination of Colchicine and Ticagrelor Inhibits Carrageenan-Induced Thrombi in Mice

The formation of a thrombus is closely related to oxidative stress and inflammation. Colchicine is one of the most commonly prescribed medication for gout treatment, with anti-inflammation and antioxidative stress properties. Therefore, we speculated that it is possible for colchicine to treat thrombosis.

In this study, we used carrageenan to induce thrombosis in BALB/c mice and fed mice with colchicine, ticagrelor, and their combination, respectively. We found colchicine inhibited carrageenan-induced thrombi in mouse tail, and the inhibition was enhanced by ticagrelor.

In vitro, colchicine inhibited thrombin-induced retraction of human platelet clots. Mechanically, colchicine inhibited platelet activation by reducing the expression of platelet receptors, protease-activated receptor 4 (PAR4) and CD36, and inactivating of AKT and ERK1/2 pathways.

Furthermore, in human umbilical vein endothelial cells (HUVECs), colchicine showed antioxidative stress effects through increasing protein expression of glutathione peroxidase-1 (GPx-1), and mRNA levels of forkhead box O3 (FOXO3a) and superoxide dismutase 2 (SOD2). In RAW264.7 cells, colchicine reduced LPS-enhanced inflammatory response through attenuating toll-like receptor 4 (TLR4) activation.

In addition, colchicine reduced LPS or ox-LDL-induced monocyte adhesion to HUVECs by inhibiting intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) levels. Taken together, our study demonstrates that colchicine exerts antithrombotic function by attenuating platelet activation and inhibiting oxidative stress and inflammation. We also provide a potential new strategy for clinical treatment.

Thermal and acidic denaturation of phycocyanin from Arthrospira platensis: Effects of complexation with λ-carrageenan on blue color stability

The pH and temperature sensitivity of the natural blue pigment phycocyanin from Arthrospira platensis limits its application as food colorant. This study examines the effect of protein stabilization by the anionic polysaccharide λ-carrageenan on phycocyanins color appearance at pH 2.5-6.0, unheated and after heat treatments (70/90 °C). Electrostatic interactions, hydrophobic interactions, hydrogen bonds and disulfide-bridges were assessed by adding NaCl, urea and dithiothreitol (DTT) to the samples.

Measurements of the zeta potential, transmittance and two-dimensional gel electrophoresis coupled to mass spectrometry confirmed electrostatic interactions around the zero surface charge of phycocyanin over a broad pH range (∼4.1-6.4). Despite a color shift towards turquoise, the color remained stable during heating, especially below of pH 3.5.

Precipitation was inhibited over the entire pH range. Overall, electrostatic complexation of phycocyanin and λ-carrageenan is a promising technique to stabilize proteinaceous colorants, helping to reduce food waste and foster a shift to renewable materials.

Spray-drying microencapsulation of tea extracts using green starch, alginate or carrageenan as carrier materials

Tea industry generates many by-products which could be used to produce and incorporate bioactive tea extracts (TE) into nutraceuticals, cosmetics and/or clinical applications. However, sensibility to external factors is a major disadvantage hindering its utilization.

This study deals with the implementation and characterization of suitable biopolymer delivery systems based on starch, carrageenan or alginate, as microencapsulation, to stabilize and protect TE through innovative thin-carbohydrate-coated formulations.

Carrageenan

from NACALAI TESQUE

07350-94 | 10G: 24.50 EUR

CARRAGEENAN

from PhytoTechnology Laboratories

C257 | 1KG: 632.46 EUR

Carrageenan

from Bio Basic

CN1138 | 500g: 101.76 EUR

Carrageenan

from TargetMol Chemicals

T35327-10mg | 10mg: Ask for price

Carrageenan

from TargetMol Chemicals

T35327-1g | 1g: Ask for price

Carrageenan

from TargetMol Chemicals

T35327-1mg | 1mg: Ask for price

Carrageenan

from TargetMol Chemicals

T35327-50mg | 50mg: Ask for price

Carrageenan

from TargetMol Chemicals

T35327-5mg | 5mg: Ask for price

λ-Carrageenan

from NACALAI TESQUE

09186-04 | 5G: 21.00 EUR

κ-Carrageenan

from TargetMol Chemicals

T38499-10mg | 10mg: Ask for price

κ-Carrageenan

from TargetMol Chemicals

T38499-1g | 1g: Ask for price

κ-Carrageenan

from TargetMol Chemicals

T38499-1mg | 1mg: Ask for price

κ-Carrageenan

from TargetMol Chemicals

T38499-50mg | 50mg: Ask for price

κ-Carrageenan

from TargetMol Chemicals

T38499-5mg | 5mg: Ask for price

Carrageenan, Iota

from Glycomatrix

40300040-1 | 100 g: 52.41 EUR

Carrageenan, Iota

from Glycomatrix

40300040-2 | 500 g: 168.46 EUR

Carrageenan, Kappa

from Glycomatrix

40300044-1 | 100 g: 35.99 EUR

Carrageenan, Kappa

from Glycomatrix

40300044-2 | 500 g: 146.28 EUR

TE were spray-dried and microencapsulated in recycled carrier materials (alginate, carrageenan or starch). Product yields varied from 55 to 58%. High microencapsulation and loading efficiencies were achieved (60-93% and 65-84%, respectively). Antioxidant capacity varied from 32 to 46 g Trolox/100 g extract, within different carrier-systems; which also showed promising rheological and UV-protective properties when transformed into gels. Total phenolic content, particle-size distribution, HPSEC-analysis, SEM-analysis and FTIR-analysis were also performed.

In sum, this paper characterizes and discusses the high potential of these recycled carbohydrate-coated microparticles for future applications.