Novel mitophagy inducer alleviates lupus nephritis by reducing myeloid cell activation and autoantigen presentation

Lupus nephritis (LN) is one of the most severe manifestations of systemic lupus erythematosus (SLE), but its mechanism of onset remains unclear. Since impaired mitophagy has been implicated in multiple organs in SLE, we hypothesized that mitophagy dysfunction is critical in the development of LN and that pharmacologically targeting mitophagy would ameliorate this disease. Therefore, lupus-prone MRL/MpJ-Faslpr (MRL/lpr) and NZBWF1/J mice were treated with a novel mitophagy inducer, UMI-77, during their onset of LN. This treatment effectively mitigated kidney inflammation and damage as assessed by histology and flow cytometry. Furthermore, dendritic cell (DC)-T-cell coculture assay indicated that UMI-77 treatment attenuated DC function that would drive T-cell proliferation but did not directly influence the potent T-cell proliferation in lupus mice. UMI-77 also restored mitochondrial function and attenuated proinflammatory phenotypes in lupus DCs. Adoptive transfer of DCs from MRL/lpr mice augmented serum anti-dsDNA IgG, urine protein and T-cell infiltration of the kidney in MRL/MpJ mice, which could be prevented by either treating lupus donors in vivo or lupus DCs directly with UMI-77. UMI-77 also restored mitochondrial function in myeloid cells from patients with LN in vitro as evidenced by increased ATP levels. Thus, enhancing mitophagy in SLE restrains autoimmunity and limits kidney inflammation for LN development. Hence, our findings suggest targeting mitophagy as a tangible pathway to treat LN.

Physiologically-based pharmacokinetic modeling of the drug-drug interaction between ivacaftor and lefamulin in cystic fibrosis patients

Lefamulin is being evaluated as a treatment for bacterial exacerbations in cystic fibrosis (CF). Ivacaftor is approved for the treatment of patients with CF. Lefamulin is a moderate CYP3A inhibitor and co-administration with ivacaftor may result in a drug-drug interaction (DDI). A CF population was built based on literature using the Simcyp Simulator. A previously developed and validated physiologically-based pharmacokinetic (PBPK) model for ivacaftor was used. A PBPK model for lefamulin was developed and verified. Predicted concentrations and pharmacokinetic (PK) parameters for both ivacaftor and lefamulin in healthy subjects and patients with CF were in reasonable agreement with observed data (within 1.4-fold, majority within 1.25-fold). The lefamulin model as a CYP3A4 perpetrator was validated using a different Ki value for oral (p.o.) and intravenous (i.v.) routes. The simulated changes in area under the curve of ivacaftor in patients with CF when co-administered with p.o. and i.v. lefamulin were weak-to-moderate. The predicted change in ivacaftor PK when co-administered with oral lefamulin was less than observed between ivacaftor and fluconazole. These results suggest a low liability for a DDI between lefamulin and ivacaftor in patients with CF.

Urate-Lowering Drugs and Muscle Injury: A Systematic Review and Network Meta-Analysis

Several urate-lowering drugs have been linked to muscle injury. This study investigated the association of oral urate-lowering drugs with the risk of muscle injury by performing a network meta-analysis of randomized and non-randomized controlled trials. A systematic search of MEDLINE, via PubMed, the ClinicalTrials.gov website, and the Cochrane Central Register of Controlled Trials was conducted to identify relevant studies with a primary outcome of "all muscle injuries." A random-effects model was used to perform a frequentist network meta-analysis to estimate whether there was significant heterogeneity among the studies. In total, 32 studies including 28,327 participants with 2694 (9.5%) "all muscle injuries" were assessed, and the overall risk of bias was judged to be low to moderate. No statistically significant differences were found between placebo and 6 urate-lowering therapies: allopurinol (risk ratio, RR, 1.05; 95% confidence interval, 95%CI, 0.63-1.73), febuxostat (RR 1.10, 95%CI 0.71-1.70), lesinurad (RR 7.00, 95%CI 0.31-160.36), lesinurad concomitant with allopurinol (RR 0.85, 95%CI 0.34-2.11), lesinurad concomitant with febuxostat (RR 1.97, 95%CI 0.55-7.03), and topiroxostat (RR 0.99, 95%CI 0.37-2.65). The findings suggest that there is little need to consider the risk of muscle injury when using urate-lowering drugs in the clinical setting.

Safety and Pharmacokinetics Following Oral or Intravenous Lefamulin in Adults With Cystic Fibrosis

PURPOSE

Methicillin-resistant Staphylococcus aureus infections are increasing in prevalence in patients with cystic fibrosis (CF) and are associated with worsening lung function and increased mortality. Lefamulin is a pleuromutilin antimicrobial approved to treat community-acquired bacterial pneumonia based on potent in vitro activity and clinical efficacy. This Phase I, open-label, randomized crossover study assessed the safety and pharmacokinetic profile of oral and intravenous (IV) lefamulin in adults with CF.

METHODS

The study comprised 2 dosing periods in which adults with CF (N = 13) received a single dose of lefamulin via a 150-mg IV infusion or 600-mg immediate-release orally administered tablet, separated by a 4- to 7-day washout period. Pharmacokinetic and safety parameters were assessed after lefamulin treatment.

FINDINGS

Single doses of lefamulin administered via oral tablet or IV infusion resulted in comparable drug exposure, and sputum analysis suggested rapid penetration of lefamulin into the lung. Comparison of the present results with those obtained from prior single-dose studies of healthy volunteers indicate no meaningful difference in the pharmacokinetic properties of lefamulin in patients with CF. Treatment-emergent adverse events were consistent with previous reports, and the majority were mild in severity.

IMPLICATIONS

These results show similar lefamulin pharmacokinetic and safety profiles between patients with CF and healthy volunteers receiving the same oral and IV doses, suggesting no need for lefamulin dose adjustment in patients with CF and indicating the potential of lefamulin as therapy for lung infections in patients with CF.

CLINICALTRIALS

gov identifier: NCT05225805.

7-Year (2015-21) longitudinal surveillance of lefamulin in vitro activity against bacterial pathogens collected worldwide from patients with respiratory tract infections including pneumonia and characterization of resistance mechanisms

OBJECTIVES

Lefamulin (Xenleta™), a pleuromutilin antibiotic, was approved for the oral and IV treatment of community-acquired bacterial pneumonia (CABP) in adults in 2019/2020. This study evaluated the in vitro activity of lefamulin and comparators against 19 584 unique bacterial isolates collected from patients with community-acquired respiratory tract infections and hospitalized patients with pneumonia within the global SENTRY Antimicrobial Surveillance Program during 2015-21.

METHODS

Isolates were susceptibility tested by the CLSI broth microdilution method, and resistance mechanisms were investigated in isolates with elevated lefamulin MICs.

RESULTS

Lefamulin exhibited potent antibacterial activity against the most common and typical CABP pathogens tested, including Streptococcus pneumoniae [MIC50/90, 0.06/0.25 mg/L; 99.9% susceptible (S)], Staphylococcus aureus (MIC50/90, 0.06/0.12 mg/L; 99.6% S), Haemophilus influenzae (MIC50/90, 0.5/2 mg/L; 99.1% S) and Moraxella catarrhalis (MIC50/90, 0.06/0.12 mg/L; 100.0% S). Potent activity was also observed against the less common pneumonia pathogens: β-haemolytic (MIC50/90 of 0.03/0.06 mg/L) and viridans group Streptococcus spp. (MIC50/90 of 0.06/0.25 mg/L) and Haemophilus parainfluenzae (MIC50/90 of 1/4 mg/L). Lefamulin's activity was not adversely affected by resistance to macrolides, penicillin, tetracyclines, fluoroquinolones and other resistance phenotypes. Non-susceptibility/resistance to lefamulin was rare and primarily determined by ribosomal protection through vga(A) variants in S. aureus, overexpression of AcrAB-TolC efflux pump in H. influenzae or modifications in L3, L4 and 23SrRNA in Streptococcus spp.

CONCLUSIONS

Based on the coverage of the most important CABP pathogens and lacking cross-resistance, lefamulin may represent a valuable empirical treatment option for ambulatory and hospitalized patients with CABP, particularly in settings with high prevalence of resistance.

Target attainment of intravenous lefamulin for treatment of acute bacterial skin and skin structure infections

OBJECTIVES

Lefamulin is a pleuromutilin antibiotic approved for the treatment of community-acquired bacterial pneumonia (CABP). Its spectrum of activity, good penetration into soft tissues and low rates of cross-resistance also make lefamulin a potentially valuable option for treatment of acute bacterial skin and skin structure infections (ABSSSIs). A Phase 2 trial of lefamulin for ABSSSI indicated similar efficacy of 100 and 150 mg q12h IV dosing regimens. In the present study, the potential of lefamulin for this indication was further evaluated from a translational pharmacokinetic/pharmacodynamic perspective.

METHODS

PTA was determined for various dosages using Monte Carlo simulations of a population pharmacokinetic model of lefamulin in ABSSSI patients and preclinical exposure targets associated with bacteriostasis and a 1-log reduction in bacterial count. Overall target attainment against MSSA and MRSA was calculated using lefamulin MIC distributions.

RESULTS

Overall attainment of the bacteriostasis target was 94% against MSSA and 84% against MRSA for the IV dosage approved for CABP (150 mg q12h). Using the same target, for the 100 mg q12h regimen, overall target attainment dropped to 68% against MSSA and 50% against MRSA. Using the 1-log reduction target, overall target attainment for both regimens was <40%.

CONCLUSIONS

Lefamulin at the currently approved IV dosage covers most Staphylococcus aureus isolates when targeting drug exposure associated with bacteriostasis, suggesting potential of lefamulin for the treatment of ABSSSIs. Lefamulin may not be appropriate in ABSSSI when rapid bactericidal activity is warranted.

Eu3+-Modified Covalent Organic Frameworks for the Detection of a Vinyl Chloride Monomer Exposure Biomarker

The vinyl chloride monomer (VCM), a common raw material in the plastics industry, is one of the environmental pollutants to which humans are mostly exposed. Thiodiglycolic acid (TDGA) in human urine is a specific biomarker of its exposure. TDGA plays an important role in understanding the relationships between exposure to the VCM and the identification of subgroups that are at increased risk for disease diagnosis. Therefore, its detection is of great significance. Here, we designed and established a ratiometric fluorescent sensor for TDGA by using Eu3+ as a bridge connecting the covalent organic framework (COF) and the energy donor molecule 2,6-dipicolinic acid (DPA) and named it DPA/Eu@PY-DHPB-COF-COOH. The sensor not only possesses the advantages of a ratiometric fluorescent sensor that can provide built-in self-calibration to correct a variety of target-independent factors but also presents high selectivity and high sensitivity. Currently, there are only a few reports on the detection of TDGA, and to the extent of our knowledge, this report is the first work on the detection of TDGA based on a COF system; so, it has an important reference value and lays a solid foundation for designing advanced sensors of TDGA.

Hydrophobic/hydrophilic separation performance evaluation of a mixed-mode ionic liquid embedded stearyl thioglycolate functionalized silica stationary phase

In this work, a novel imidazolium ionic liquid embedded multifunctional chromatographic stationary phase (Sil-AVI-ST) was synthesized by the radical-mediated thiol-ene click reaction. A wide range of samples including hydrophilic sulfonamides, vitamins and nucleosides/bases as well as hydrophobic phthalates, bisphenols, alkylphenols and steroid hormones were selected to evaluate the separation ability of the newly obtained Sil-AVI-ST. As expected, an efficient separation of the above tested analytes was successfully achieved in different chromatographic modes. It was proved that multiple stationary phase-analyte interaction forces promoted the selective separation. The Sil-AVI-ST column provided multiple retention mechanisms, enabling the efficient separation of diverse analytes with different polarity. More importantly, embedding a polar ligand (1-allyl-3-vinyl-imidazolium) could improve the separation efficiency of long-chain alkyl bonded stationary phases for hydrophilic analytes, and the developed Sil-AVI-ST column could also realize the detection of hydrophobic analytes under water-rich conditions, which is impossible for the conventional hydrophobic columns. Therefore, the newly prepared Sil-AVI-ST stationary phase has a good practical application potential.

Reliable strategy of sensitive fluorescent nanoprobe for sensing silver nanoparticles using specific carbon dots derived from mercaptoacetic acid and melamine

Nitrogen and sulfur element co-decorated carbon nanodots (N,S-CDs) were synthesized by solid state hydrothermal method utilizing mercaptoacetic acid and melamine as the precursors. The obtained N,S-CDs had wonderful optical and chemical stability. The experimental results demonstrated that silver nanoparticles (AgNPs) could noticeably quench the fluorescence of N,S-CDs. The quenching of fluorescence signal from the presence of AgNPs may be attributed to inner filter effect. The crafted nanoprobe for sensing AgNPs was endowed with some specialties such as simplicity, excellent selectivity and sensitivity, environmental friendliness and low cost. The probe exhibited specific linearity from 0.024 to 1.77 nM, and was endowed a good limit of detection down to 0.022 nM. The experimental results demonstrated that the built probe could be an efficient tool for AgNPs detection and had a prospective application, and also provided a new direction for establishing innovative method for determining and monitoring pollutants from nanoparticles.

Spectrophotometric quantitative analysis of lesinurad using extractive acid dye reaction based on greener selective computational approach

Computational studies introduce an integral approach for finding greener methods through testing solvents for reactions and extractions. Lesinurad is a novel selective uric acid reabsorption inhibitor prescribed for the treatment of chronic gout. Computational calculations were achieved to choose the best acid dye used for sensitive visible spectrophotometric determination of lesinurad. The calculations were performed using Gaussian 03 software based on density functional theory method with B3LYP/6-31G(d) basis set. The obtained results revealed that bromophenol blue was preferred for lesinurad than other acid dyes based on the higher calculated interaction energy. The described method was based on the reaction of lesinurad with the theoretically selected acid dye bromophenol blue to form a yellow ion-pair complex. The absorption spectra showed maximum sharp peaks at 418 nm. Different factors affecting the reaction were optimized. Beer's law was demonstrated over the concentration range of 2-12 μg/mL lesinurad. The described reaction was utilized for the spectrophotometric determination of lesinurad in pure form and in the pharmaceutical preparation. The greenness of the described method was assessed using four different tools namely, the national environmental method index, the analytical eco-scale, the green analytical procedure index and the novel analytical greenness metric. The proposed method seemed to be superior to the reported HPLC method with respect to the metrics of the greenness characters.

Quantifying H2O2 by ratiometric fluorescence sensor platform of N-GQDs/rhodamine B in the presence of thioglycolic acid under the catalysis of Fe3

In the presence of thioglycolic acid (TGA) and under the catalysis of Fe³⁺, a simple, rapid, sensitive, selective and effective ratiometric fluorescence sensor platform based on the mixed physically blue nitrogen-doped graphene quantum dots (N-GQDs) as probe signals and orange rhodamine B as internal standard signals has been constructed for analysis of H₂O₂ in human serum. TGA is the key factor for fluorescence response toward H₂O₂ by N-GQDs and the mechanism is H₂O₂ reacts speedily with TGA under the catalysis of Fe³⁺, and produces intermediate of superoxide anions (O₂^-), which accepts electrons from N-GQDs, and generates graphene oxide, causing the fluorescence quench of N-GQDs. Compared with N-GQDs probe, the sensitivity of the ratiometric fluorescence sensor platform of N-GQDs/rhodamine B for analysis of H₂O₂ has been improved by nearly 5-folds. Under the optimum conditions, F_λ=580nm/F_λ=440nm has a good linear relationship with the concentration of H₂O₂ and the detection limit of H₂O₂ is 0.46 μmol/L with 3.5% RSD. The established sensor platform has been successfully used for probing H₂O₂ in human serum with satisfactory results. The superior performance of the probe lies in its high selectivity and can be directly employed in detecting H₂O₂ in serum samples without any sample pretreatment procedures.

[Effect of Curcumin on Apoptosis of Acute T-Lymphoblastic Leukemia Cells induced by UMI-77 and Its Related Mechanism]

AbstractObjective: To explore the effect and mechanism of curcumin on human T-cell acute lymphoblastic leukemia (T-ALL) cell apoptosis induced by Mcl-1 small molecule inhibitors UMI-77.

METHODS

T-ALL cell line Molt-4 was cultured, and the cells were treated with different concentrations of curcumin and Mcl-1 small molecule inhibitor UMI-77 for 24 h. The MTT method was used to detect the cell survival rate after different treatment; According to the results of curcumin and UMI-77, the experimental settings were divided into control group, curcumin group (20 μmol/L curcumin treated cells), UMI-77 group (15 μmol/L Mcl-1 small molecule inhibitor UMI-77 treated cells) and curcumin+ UMI-77 group (20 μmol/L curcumin and 15 μmol/L Mcl-1 small molecule inhibitor UMI-77 treated cells), MTT method was used to detect cell proliferation inhibition rate, Annexin V-FITC/PI double staining method and TUNEL staining were used to detect cell apoptosis, DCFH-DA probe was used to detect cell reactive oxygen species, JC-1 fluorescent probe was used to detect mitochondrial membrane potential, Western blot was used to detect the expression levels of apoptosis-related proteins and Notch1 signaling pathway-related proteins.

RESULTS

After the treatment of Molt-4 cells with different concentrations of curcumin and Mcl-1 small molecule inhibitor UMI-77, the cell survival rate was decreased (P<0.05); Compared with the control group, the cell proliferation inhibition rate of the curcumin group and the UMI-77 group were increased, the apoptosis rate of cell was increased, the level of ROS was increased, the protein expression of Bax, Caspase-3 and Caspase-9 in the cells were all increased, and the protein expression of Bcl-2 was reduced (P<0.05); Compared with the curcumin group or UMI-77 group, the cell proliferation inhibition rate and apoptosis rate of the curcumin+UMI-77 group were further increased, and the level of ROS was increased. At the same time, the protein expression of Bax, Caspase-3 and Caspase-9 in the cells were all increased, the protein expression of Bcl-2 was reduced (P<0.05); In addition, the mitochondrial membrane potential of the cells after curcumin treatment was decreased, and the proteins expression of Notch1 and HES1 were reduced (P<0.05).

CONCLUSION

Curcumin can enhance the apoptosis of T-ALL cells induced by Mcl-1 small molecule inhibitor UMI-77 by reducing the mitochondrial membrane potential, the mechanism may be related to the inhibition of Notch1 signaling pathway.

Thioglycolic acid-modified AuNPs as a colorimetric sensor for the rapid determination of the pesticide chlorpyrifos

Herein, we report the preparation of a gold nanoparticle-thioglycolic acid (TGA@AuNP) suspension for the label-free colorimetric detection of the organophosphorus pesticide chlorpyrifos. This colorimetric sensor was synthesized by a one-pot method, providing thioglycolic acid (TGA)-modified gold nanoparticles with a negatively charged surface. The formation of TGA@AuNPs was confirmed by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and dynamic light scattering (DLS). In addition, chlorpyrifos was quantitatively determined by UV-vis spectrophotometry. The modification time, TGA concentration, pH, incubation time, temperature, ionic strength, and interference of other pesticides were also investigated. The synthesized TGA@AuNP colorimetric sensor possesses a detection limit as low as 20 μg L^-1 and a selective sensing response, and the detection time is less than 2 minutes. In addition, this method can also be applied to detect various practical samples in life, such as environmental water samples and tea.

The protective effects of erdosteine on subacute diazinon-induced oxidative stress and inflammation in rats

In today's world, pesticides are commonly used to control pests and in advanced agriculture. As an organophosphorus insecticide (OPI), diazinon (DZN) is a commonly used substance. However, the widespread usage of DZN increases the probability of incidence of toxication. This toxication has been reported to be shaped not through cholinergic syndromes that are experienced as a result of acetylcholinesterase inhibition, which is the primary effect of these cases. It is rather shaped by the altering of the facilitation of oxidative stress and inflammatory response. In this study, the protective effect of administering erdosteine (ERDOS) subacute DZN exposure was investigated. A total of 24 male Wistar albino rats were separated into 4 groups (with 6 rats in each group), namely, the control, DZN (15 mg/kg/day), ERDOS (10 mg/kg/day), and DZN + ERDOS (15 mg/kg/day DZN + 10 mg/kg/day ERDOS) groups. These medications were given through oral gavage for 28 days. With the whole blood, plasma, and serum samples taken from the rats, oxidant-antioxidant parameters and cytokine levels were measured. The MDA and NOx levels and SOD and CAT enzyme activities of the DZN group were higher than those of the control group, while the GSH levels and TAC and GPx activities of the DZN group were lower than those of the control group (p < 0.05). It was also found that cytokine (IL-1β, IL-10, and TNF-α) levels in the DZN group were higher than those in the control group (p < 0.05). On the other hand, the ERDOS implementations were detected to ameliorate the harmful effects of DZN on the oxidant-antioxidant parameters and cytokine levels (p < 0.05). Conclusively, besides the known mucolytic efficacy of ERDOS, it may also be stated to display free radical scavenger, antioxidant, and anti-inflammatory characteristics to inhibit some proinflammatory cytokines that are specifically involved in oxidative stress. Additionally, the ameliorating property of ERDOS can be benefited from in possible DZN-induced toxication cases.

The influence of erdosteine administration on lead-induced oxidative stress in rat muscle

Lead-exposure is known to disrupt the redox balance of tissues leading to oxidative stress. Due to the fact that a mucolytic drug, erdosteine, exerts also antioxidant properties, we decided to perform a pilot study on rats to evaluate its therapeutic potency in lead poisoning. Male Wistar rats were divided randomly into the following seven groups having 10 animals in each. Group I served as the control group. During 8-week period, rats in groups II-IV, except standard alimentation, received: erdosteine in a dose 350 mg/kg (collateral control group), 1200 ppm of lead acetate in drinking water and placebo, as well as the same doses of lead and erdosteine, respectively. Rats in group V-VII received 1200 ppm of lead acetate in drinking water for the initial 6-week period and then administered: placebo, erdosteine and EDTA for 2 weeks, respectively. The levels of malondialdehyde (MDA) were significantly higher in groups III and V compared to the control group. The activities of catalase (CAT) were significantly higher in groups IV, V, and VI compared to the control group. The activities of glutathione-S-transferase (GST) were significantly lower in group II and significantly higher in groups VI and VII compared to the control group, while the activities of glutathione reductase (GR) were significantly lower in group III and significantly higher in group VI. Erdosteine has an effect of protection against lead-induced oxidative stress which is not worse than that of EDTA.

Bioactivities and modes of action of VUAA1

BACKGROUND

The compound 2-((4-ethyl-5-(pyridin-3-yl)-4H-1,2,4-triazol-3-yl)thio)-N-(4-ethylphenyl) acetamide (VUAA1) is reported to be an odorant receptor co-receptor (Orco) agonist in insects with potential use as an insect repellent. For this study, the biological activity of VUAA1 was investigated in several bioassays with Aedes aegypti, including adult contact, spatial repellency, and larval repellency assays, as well as topical, injection, and feeding toxicity assays. Neurophysiological action was further explored by analysis of fruit fly central nervous system firing, cockroach axon recordings, patch clamp analysis of Kv2 potassium channel, and acetylcholinesterase inhibition studies. Finally, the metabolic impact on the toxicity of VUAA1 was explored by applying it in combination with established metabolic synergists.

RESULTS

In repellency and bite protection screens, VUAA1 showed little activity against adult mosquitoes, apparently due to its low volatility, since its effectiveness was increased by heating or mixing with transfluthrin acid and citronella oil. It did produce measurable repellency of mosquito larvae that was more potent than N,N-diethyl-m-toluamide (DEET). Overall, VUAA1 showed low acute toxicity to both insects and mice, and it was weakly synergized by triphenyl phosphate. There was no observed cross-resistance in a pyrethroid-resistant strain of Anopheles gambiae. VUAA1 showed a two-phase effect on the central nervous system, with neuroexcitation at 1 μmol L^-1 and an inhibitory effect at 100 μmol L^-1 that may relate to block of Kv2 potassium channels.

CONCLUSIONS

VUAA1 presented low toxicity, similar to other insect repellents. Its limited solubility, low volatility, and resulting poor adult repellency without additional adjuvants may restrict the utility of VUAA1 in typical public health applications. © 2020 Society of Chemical Industry.

Synthesis of Cadmium Telluride Nanoparticles Using Thioglycolic Acid, Thioglycerol, and L-Cysteine

Cadmium telluride (CdTe) nanoparticles (NPs) are known for their unique physical and chemical properties. NP synthesis via a size-controlled procedure has become an intriguing research topic because NPs exhibit novel optical and physical properties depending on their size. Their sizes and properties can vary depending on the types and concentrations of stabilizers, which are bound to the surface of the NPs and protect the NPs from aggregation. In this study, we synthesized CdTe NPs stabilized by thioglycolic acid (TGA), 1-thioglycerol (TGC), and L-cysteine (L-C). The ratio of stabilizer to Cd²⁺ was 1:2.4. Transmission electron microscopy (TEM), X-ray diffraction (XRD), and photoluminescence (PL) were employed for characterization of the NPs. The average sizes of the synthesized NPs were 4.2, 4.1, and 3.7 nm for TGA, TGC, and L-C, respectively. The maximum fluorescent emission peaks of the three NP solutions were at 554.9, 551.6, and 538.3 nm for TGA, TGC, and L-C, respectively. The produced particles were crystalline in structure with a face-centered cubic (fcc) system.

Different chemometric assisted approaches for spectrophotometric quantitative analysis of lesinurad and allopurinol

Three chemometric assisted spectrophotometric approaches were designed for precise quantitative analysis of lesinurad and allopurinol, in their recently FDA approved combination pharmaceutical dosage form. By utilizing the recorded absorption spectral data of lesinurad and allopurinol mixtures, principle component regression, partial least squares and genetic algorithm partial least squares were developed and compared for the spectrophotometric quantitative analysis of the cited drugs in their binary mixture. Experimental design for different concentrations of the studied drugs was done based on the spectral sensitivity and the commercial ratio of the two drugs in the combined pharmaceutical dosage form. Optimization of the described models was done using five-levels, two factors experimental design principle. Quantitative assay of the two drugs in Duzallo® tablet was successfully done and the data obtained was statistically compared with the results of another published HPLC quantitative analytical method.

Micelle-Enhanced conventional and synchronous spectrofluorimetric methods for the simultaneous determination of lesinurad and febuxostat: Application to human plasma

A simple synchronous spectrofluorimetric method was developed for simultaneous determination of lesinurad and febuxostat. The investigated drugs were measured at 294 and 329 nm, respectively in the presence of each other without interference at Δλ of 50 nm (Method I). The different experimental parameters affecting the fluorescence intensities were carefully studied and optimized. The maximum synchronous fluorescence intensities were obtained at pH 6.5 using borate buffer and distilled water was used as a diluting solvent. Excellent linearity ranges were obtained using 20.0-500.0 ng mL^-1 and 1.0-80.0 ng mL^-1 for lesinurad and febuxostat, respectively. The method exhibited high sensitivity with detection limits down to 4.0 ng mL^-1 and 0.01 ng mL^-1 and quantitation limits down to 12.12 ng mL^-1 and 0.02 ng mL^-1, respectively. Recovery percentages ranged from 97.68 to 103.37% were obtained upon spiking of human plasma samples, indicating high bioanalytical applicability. Concerning Method II, methanolic solution of lesinurad was measured spectroflourimetrically with λ_excitation at 290 nm and λ_emission at 341 nm with high sensitivity using borate buffer of pH 6.5 and methanol as a diluting solvent. A considerable enhancement of the fluorescence intensity was achieved by using 1.0% w/v cetremide as a micellar system. The method was rectilinear over the concentration range of 3.0-80.0 ng mL^-1 with detection and quantitation limits down to 0.47 and 1.42 ng mL^-1, respectively. The developed method was efficiently applied for the estimation of the cited drug in spiked human plasma with high recovery percentages (98.58-101.64%). The methods were validated according to the ICH guidelines and further applied to commercial tablets with good results.

Spectrophotometric determination of lesinurad and allopurinol in recently approved FDA pharmaceutical preparation

Different spectrophotometic quantitative analytical methods have been developed and applied for quantitative determination of lesinurad and allopurinol in their newly FDA approved pharmaceutical dosage form. lesinurad was quantitatively analyzed based on its unique UV spectra without any mathematical processing step. Direct quantitative analysis was done through its recorded zero-order absorption spectra at 290 nm without any contribution from allopurinol. On the other hand two processing mathematical spectrophotometric methods were applied to enable quantitative analysis of allopurinol through resolving of the recorded overlapping UV spectra between lesinurad and allopurinol. Ratio difference and ratio derivative spectra manipulated methods were enabled successful quantitative determination of allopurinol without any contribution from lesinurad. The described methods were successfully applied for the quantitative analysis of the two drugs in Duzallo ® pharmaceutical dosage form.

A highly selective and simple fluorescent probe for salbutamol detection based on thioglycolic acid-capped CdTe quantum dots

In this paper, a highly fluorescent water-soluble CdTe quantum dots (CdTe QDs) stabilized with thioglycolic acid (TGA) were synthesized for the quantitative and selective determination of salbutamol (SAL). When ten different of 2.09 × 10^-6 mol L^-1 alpha-2 adrenoceptor agonist were added to 4.38 × 10^-4 mol L^-1CdTe QDs solution, the fluorescence signal of the CdTe QDs quenched obviously by SAL with 57.32% and 0.815% - 7.00% for other nine kinds of veterinary medicine, such as tulobuterol, fenoterol, phenylethanamine A, simatero, penbutolol, clenbuterol, ractopamine, terbutaline and clorprenaline. The result shows that the CdTe QDs is highly sensitive sensor for SAL. The quenching mechanism has been investigated by absorption spectroscopy and K_SV at different temperatures, and shew a static quenching process than dynamic quenching. Under the optimal conditions, respectively the straight line equation (F₀/F = 0.1491 × 10⁶ C + 1.3078) was found between the relative fluorescence intensity and the concentration of SAL was in the range of 6.27 × 10^-8 to 2.09 × 10^-7 mol L^-1, and the limit of detection was 4.2 × 10^-8 mol L^-1. The proposed method has been applied to the determination of SAL in pig urine samples.

Application of different spectrofluorimetric methods for determination of lesinurad and allopurinol in pharmaceutical preparation and human plasma

Lesinurad and allopurinol combination is newly FDA approved for treatment of patients suffering from hyperuricemia associated with uncontrolled gout. In the present work, two different highly sensitive, selective and accurate fluorescence spectroscopic methods were developed for quantitative analysis of lesinurad and allopurinol in their pharmaceutical dosage form without any tedious operation procedure. Lesinurad was quantitatively analyzed based on its unique native fluorescence nature. Lesinurad fluorescence emission was quantitatively determined at 343 nm after excitation at 288 nm without any interference from allopurinol. Allopurinol, has free terminal secondary amino group, reacted with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBDCl) through nucleophilic substitution mechanism forming highly fluorescent dark yellow fluorophore. Allopurinol was quantitavely analyzed based on measurement the emission fluorescence intensity of the fluorescent dark yellow fluorophore at 535 nm after excitation at 465 nm. Different parameters which affect the described methods of the studied drugs were carefully checked and optimized. Calibration graphs were found to be linear over the concentration range of 0.25-4.0 μg/mL for lesinurad and 0.2-20 μg/mL for allopurinol. The proposed methods were successfully applied for the quantitative analysis of the two drugs in Duzallo® pharmaceutical dosage form and spiked human plasma.

Lefamulin: A Novel Semisynthetic Pleuromutilin Antibiotic for Community-acquired Bacterial Pneumonia

Community-acquired bacterial pneumonia (CABP) remains a significant cause of morbidity and mortality worldwide. Antimicrobial resistance, including in pathogens that cause CABP, continues to spread at an alarming rate. Because of these factors, the development of new antibiotic classes is urgently needed. Lefamulin, previously known as BC-3781, is a semisynthetic pleuromutilin antibiotic that was approved by the Food and Drug Administration for the treatment of CABP in adults. Available in both oral and intravenous formulations, lefamulin has potent in vitro activity against both typical and atypical CABP pathogens. The first pleuromutilin to be used systemically in humans, lefamulin has a unique mechanism of action that inhibits protein synthesis by preventing the binding of tRNA for peptide transfer. This review summarizes the available data on lefamulin, including recent evidence from 2 phase III clinical trials (LEAP 1 and LEAP 2), and discusses its potential role in the treatment of CABP.

Simultaneous determination of cefixime and erdosteine in combined dosage form using validated spectrophotometric methods

Four accurate and precise spectrophotometric methods were developed and validated for the simultaneous determination of a binary mixture of cefixime (CEF) and erdosteine (ERD) without previous separation. Method A was first derivative ratio spectrophotometric method (¹DD) where the amplitudes at 310 and 315 nm and the amplitude at 248 nm were chosen to simultaneously estimate CEF and ERD, respectively. Method B depends on ratio difference spectrophotometry (RDSM), in which the difference in amplitudes at 325 and 326 nm on the ratio spectrum of the mixture was directly proportional to the concentration of CEF; independent of the interfering component. Similarly, the amplitude difference between 236 and 249 nm on the ratio spectrum was used for the determination of ERD. Method C was based on simultaneous determination of CEF and ERD using classical least squares (CLS) and partial least squares (PLS) chemometric techniques. Method D was the mean centering of ratio spectra (MCR) at 313 and 237 nm for the determination of CEF and ERD respectively. The developed methods were successfully employed to the determination of CEF and ERD in laboratory prepared mixtures and dosage form showing satisfactory recoveries. Methods validation was performed according to the International Conference on Harmonization (ICH) guidelines. The obtained results were statistically compared to those of the reference method, revealing no significant difference with respect to precision and accuracy. Precision and cost effectiveness of the developed methods permit their application in quality control laboratories for the determination of the binary mixture.

One week of continuous corticosterone exposure impairs hepatic metabolic flexibility, promotes islet β-cell proliferation, and reduces physical activity in male C57BL/6 J mice

Clinical glucocorticoid use, and diseases that produce elevated circulating glucocorticoids, promote drastic changes in body composition and reduction in whole body insulin sensitivity. Because steroid-induced diabetes is the most common form of drug-induced hyperglycemia, we investigated mechanisms underlying the recognized phenotypes associated with glucocorticoid excess. Male C57BL/6 J mice were exposed to either 100ug/mL corticosterone (cort) or vehicle in their drinking water. Body composition measurements revealed an increase in fat mass with drastically reduced lean mass during the first week (i.e., seven days) of cort exposure. Relative to the vehicle control group, mice receiving cort had a significant reduction in insulin sensitivity (measured by insulin tolerance test) five days after drug intervention. The increase in insulin resistance significantly correlated with an increase in the number of Ki-67 positive β-cells. Moreover, the ability to switch between fuel sources in liver tissue homogenate substrate oxidation assays revealed reduced metabolic flexibility. Furthermore, metabolomics analyses revealed a decrease in liver glycolytic metabolites, suggesting reduced glucose utilization, a finding consistent with onset of systemic insulin resistance. Physical activity was reduced, while respiratory quotient was increased, in mice receiving corticosterone. The majority of metabolic changes were reversed upon cessation of the drug regimen. Collectively, we conclude that changes in body composition and tissue level substrate metabolism are key components influencing the reductions in whole body insulin sensitivity observed during glucocorticoid administration.

Anti-inflammatory effects of a traditional Korean medicine: Ojayeonjonghwan

OBJECTIVE

To study the anti-inflammatory properties of OJ.

CONTEXT

Ojayeonjonghwan (OJ) is a traditional Korean prescription, which has been widely used for the treatment of prostatitis. However, no scientific study has been performed of the anti-inflammatory effects of OJ.

MATERIALS AND METHODS

Peritoneal macrophages were isolated 3-4 days after injecting a C57BL/6J mouse with thioglycollate. They were then treated with OJ water extract (0.01, 0.1, and 1 mg/mL) for 1 h and stimulated with lipopolysaccharide (LPS) for different times. Nitric oxide (NO), inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, and proinflammatory cytokine levels were determined by NO assay, Western blotting, RT-PCR and ELISA.

RESULTS

NO generation and iNOS induction were increased in the LPS-activated mouse peritoneal macrophages. However, NO generation and iNOS induction by LPS were suppressed by treatment with OJ for the first time. The IC₅₀ value of OJ with respect to NO production was 0.09 mg/mL. OJ did not influence LPS-stimulated COX-2 induction, but did significantly decrease LPS-stimulated secretions and mRNA expressions of tumour necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β. Inhibition rates of TNF-α, IL-6, and IL-1β at an OJ concentration of 1 mg/mL were 77%, 88%, and 50%, respectively. OJ also suppressed the LPS-induced nuclear translocation of NF-κB. High-performance liquid chromatography showed schizandrin and gomisin A are major components of OJ.

CONCLUSIONS

OJ reduces inflammatory response, and this probably explains its positive impact on the prostatitis associated inflammation.

The relationship between the length of surface ligand and effects of CdTe quantum dots on the physiological functions of isolated mitochondria

The potential toxicity of Quantum dots (QDs) should be assessed comprehensively for their fast spreading applications. Many studies have shown the toxicity of QDs is associated with their surface ligands. In this work, two analog ligands with one carbon difference, 2-mercaptoacetic acid (TGA) and 3-mercaptopropionic acid (MPA) were used as coating materials in the syntheses of two types of CdTe QDs with similar physicochemical properties. Then the biological effects of QDs on isolated mitochondria were studied. It was found that the two types of QDs could impair mitochondrial respiration and induce mitochondrial permeability transition (MPT). However, as compared with TGA-CdTe QDs, MPA-CdTe QDs had a stronger effect on MPT. The weaker effect of TGA-CdTe QDs on MPT might be owing to their better stability and thus less amount of released Cd²⁺, which could be further explained by the stronger affinity between the ligand (TGA) and the cadmium complexes in the crystal growth of QDs. These results highlighted the importance of ligands responsible for the toxicity of QDs at the sub-cellular level.

Incidence of Propionibacterium acnes in initially culture-negative thioglycollate broths-a prospective cohort study at a Danish University Hospital

The aim of this study was to prospectively investigate the incidence of Propionibacterium acnes in thioglycollate broths reported as culture-negative at the Department of Clinical Microbiology, Rigshospitalet, to evaluate whether 5 days of incubation was enough to find all relevant cases. Five hundred thioglycollate broths reported as culture-negative after 5 days were consecutively collected and incubated for at least a further 9 days (at least 14 days of incubation in total). Only tissue samples from sterile sites of the body (n = 298), bone tissue (n = 197) and foreign material (n = 5) were included in this study. Samples were divided into two groups: infected group and control group. This made it possible to compare findings between groups, thereby making it possible to estimate the level of true-positive findings and contamination. Samples from 296 participants were included in this study. After exclusion criteria were met, P. acnes was cultured from ten out of 151 patients (6.6%) in the infected group and from one out of 138 participants (0.7%) in the control group. This resulted in more findings of P. acnes in the infected group on day 14 than on day 5 (p 0.002). Furthermore, P. acnes was cultured more often from bone tissue and tissue surrounding foreign materials on day 14 than on day 5 (p 0.04). Clinical microbiology laboratories should consider incubating thioglycollate broths for at least 14 days to find all relevant cases of P. acnes, especially when it comes to bone tissue and tissue surrounding foreign materials.

Organic-coated nanoparticulate zero valent iron for remediation of chemical oxygen demand (COD) and dissolved metals from tropical landfill leachate

The use of nanoparticulate zero valent iron (NZVI) in the treatment of inorganic contaminants in landfill leachate and polluted plumes has been the subject of many studies, especially in temperate, developed countries. However, NZVI's potential for reduction of chemical oxygen demand (COD) and treatment of metal ion mixtures has not been explored in detail. We investigated the efficiency of NZVI synthesized in the presence of starch, mercaptoacetic, mercaptosuccinic, or mercaptopropenoic acid for the reduction of COD, nutrients, and metal ions from landfill leachate in tropical Sri Lanka. Synthesized NZVI were characterized with X-ray diffraction (XRD), transmission electron microscopy, X-ray photoelectron spectroscopy, scanning electron microscopy (SEM), thermal gravimetric analysis, Fourier transform infrared spectroscopy (FTIR) and Brunauer-Emmett-Teller. Of the samples tested, Starch-NZVI (S-NZVI) and mercaptoacetic-NZVI (MA-NZVI) performed well for treatment both COD and metal mixture. The removal percentages for COD, nitrate-nitrogen, and phosphate from S-NZVI were 50, 88, and 99 %, respectively. Heavy metal removal was higher in S-NZVI (>95 %) than others. MA-NZVI, its oxidation products, and functional groups of its coating showed the maximum removal amounts for both Cu (56.27 mg g(-1)) and Zn (28.38 mg g(-1)). All mercapto-NZVI showed well-stabilized nature under FTIR and XRD investigations. Therefore, we suggest mercapto acids as better agents to enhance the air stability for NZVI since chemically bonded thiol and carbonyl groups actively participation for stabilization process.

Pineal arylalkylamine N-acetyltransferase (Aanat) gene expression as a target of inflammatory mediators in the chicken

Previously, we demonstrated that experimental peritonitis in chickens was attenuated by treatment with exogenous melatonin, while the developing inflammation decreased pineal AANAT activity. This suggested the existence of a bidirectional relationship between the activated immune system and pineal gland function. The aim of the present study was to identify the step(s) in the chicken pineal melatonin biosynthetic pathway that are affected by inflammation. Peritonitis was evoked by i.p. injection of thioglycollate solution, either 2h after the start, or 2h before the end of the light period, and the animals were sacrificed 4h later. The effect of inflammation on the expression of genes encoding enzymes participating in melatonin biosynthesis in the pineal gland, i.e. tryptophan hydroxylase 1 (Tph1), dopa decarboxylase (Ddc), arylalkylamine N-acetyltransferase (Aanat) and acetylserotonin O-methyltransferase (Asmt), was evaluated by qPCR. The pineal and serum melatonin concentration as well as the content of its precursors in the pineal gland were measured, along with the activity of the relevant biosynthetic enzymes. Developing peritonitis caused an increase in the pineal levels of the Tph1 mRNA during the night and the Asmt mRNA during the day, while nocturnal Aanat transcription was reduced. Both the pineal and serum melatonin level and the pineal content of N-acetylserotonin (NAS) were decreased during the night in birds with peritonitis. The amount and activity of pineal AANAT were significantly reduced, while the activity of HIOMT was increased under these experimental conditions. These results indicate that the observed decrease in MEL biosynthesis in chickens with developing inflammation is a result of transcriptional downregulation of the Aanat gene, followed by reduced synthesis and activity of the encoded enzyme.

The chemerin/ChemR23 system does not affect the pro-inflammatory response of mouse and human macrophages ex vivo

Macrophages constitute a major component of innate immunity and play an essential role in defense mechanisms against external aggressions and in inflammatory responses. Chemerin, a chemoattractant protein, is generated in inflammatory conditions, and recruits cells expressing the G protein-coupled receptor ChemR23, including macrophages. Chemerin was initially expected to behave as a pro-inflammatory agent. However, recent data described more complex activities that are either pro- or anti-inflammatory, according to the disease model investigated. In the present study, peritoneal macrophages were generated from WT or ChemR23(-/-) mice, stimulated with lipopolyssaccharide in combination or not with IFN-γ and the production of pro- (TNF-α, IL-1β and IL-6) and anti-inflammatory (IL-10) cytokines was evaluated using qRT-PCR and ELISA. Human macrophages generated from peripheral blood monocytes were also tested in parallel. Peritoneal macrophages from WT mice, recruited by thioglycolate or polyacrylamide beads, functionally expressed ChemR23, as assessed by flow cytometry, binding and chemotaxis assays. However, chemerin had no effect on the strong upregulation of cytokine release by these cells upon stimulation by LPS or LPS/IFN-γ, whatever the concentration tested. Similar data were obtained with human macrophages. In conclusion, our results rule out the direct anti-inflammatory effect of chemerin on macrophages ex vivo, described previously in the literature, despite the expression of a functional ChemR23 receptor in these cells.

Injection of paraoxonase 1 (PON1) to mice stimulates their HDL and macrophage antiatherogenicity

We analyzed, for the first time, the effects of recombinant PON1 (rePON1) intraperitoneal injection to C₅₇BL/6 mice on their HDL and macrophage antiatherogenic properties. Thioglycolate-treated mice were injected with either saline (Control), or rePON1 (50 μg/mouse), and 20 H post injection, their blood samples and peritoneal macrophages (MPM) were collected. A significant increase in serum and HDL-PON1 arylesterase and lactonase activities was noted. Similarly, a significant increment, by 3.8 and 2.8 fold, in MPM-PON1 arylesterase and lactonase activities, respectively, as compared to the activities in control MPM was observed. The HDL from rePON1-injected mice was resistant to oxidation by copper ions as compared to control HDL. Furthermore, enrichment of the mouse HDL with rePON1 increased its ability to induce cholesterol efflux from J774A.1 macrophage cell line, and to inhibit macrophage-mediated LDL oxidation. In MPM from rePON1-injected mice vs. control MPM, there was a significant reduction in cholesterol mass, by 42%, in association with inhibition in cellular cholesterol biosynthesis rate, by 33%, and with significant stimulation, by 65%, of human HDL-mediated cholesterol efflux from the cells. We conclude that rePON1 injection to mice improved the mice HDL and MPM antiatherogenic properties, and these effects could probably lead to attenuation of atherosclerosis development.

[Study on the estrogen derivative marked by CdTe quantum dots]

Water-soluble CdTe quantum dots (QDs) stabilized by thioglycolic acid (TGA) with high quantum yield were synthesized. And the small biomolecule 17beta-amino-estradiol was marked successfully by CdTe QDs. The analysis of UV-Vis spectroscopy, fluorescence spectroscopy, infrared spectroscopy and inverted microscope photographs showed that the surface carboxyl of CdTe quantum dots conjugated with the amino of 17beta-amino-estradiol through the activation of N-hydroxysuccinimide. 17beta-amino-estradiol marked by CdTe QDs successfully provided an experimental basis for new drug screening model.

The Stability of Thioglycollate Solutions: Part II. Miscellaneous Factors Associated with the Oxidation and Stability

The rate of oxidation of thioglycollate in aqueous solution increases with increasing pH, but when dextrose is present, neutral solutions are oxidised more rapidly than alkaline solutions. The effect of sodium metabisulphite on the oxidation was indecisive. Boiling thioglycollate solutions evolved hydrogen sulphide. Heating old solutions of thioglycollate caused regeneration of the oxidised material but the extent of this regeneration was less than might have been expected. A yellow colour in some thioglycollate solutions is believed to be due to the action of alkali on the thioglycollic acid. The tetracarboxy acid occurring in samples of the acid was isolated. It is recommended that thioglycollate media be stored in air-tight containers at as low a temperature as possible.

Factor VII deficiency impairs cutaneous wound healing in mice

Skin keratinocytes express tissue factor (TF) and are highly associated with skin wound healing. Although it has been demonstrated that perivascular TF expression in granulation tissue formed after dermal injury is downregulated during healing, studies of the mechanism of factor (F) VII, a TF ligand, in skin wound healing are lacking. We reported the use of a dermal punch model to demonstrate that low-expressing FVII mice (approximately 1% of wild type [WT]) exhibited impaired skin wound healing compared with WT controls. These low-FVII mice showed defective reepithelialization and reduced inflammatory cell infiltration at wound sites. This attenuated reepithelialization was associated with diminished expression of the transcription factor early growth response 1 (Egr-1). In vitro, Egr-1 was shown to be essential for the FVIIa-induced regulation of keratinocyte migration and inflammation. Both Egr-1 upregulation and downstream inflammatory cytokine appearance in keratinocytes depended on FVIIa/TF/protease-activated receptor 2 (PAR-2)-induced signaling and did not require subsequent generation of FXa and thrombin. The participation of Egr-1 in FVIIa-mediated regulation of keratinocyte function was confirmed by use of Egr-1-deficient mice, wherein a significant delay in skin wound healing after injury was observed, relative to WT mice. The results from these studies demonstrate an in vivo mechanistic relationship between FVIIa, Egr-1 and the inflammatory response in keratinocyte function during the wound healing process.

PECAM-independent thioglycollate peritonitis is associated with a locus on murine chromosome 2

Background

Previous studies have demonstrated that knockout or inhibition of Platelet/Endothelial Cell Adhesion Molecule (PECAM, CD31) in a number of murine strains results in impaired inflammatory responses, but that no such phenotype is seen in the C57BL/6 (B6) murine background.

Methodology/Principal Findings

We have undertaken a quantitative trait locus (QTL) mapping effort between FVB/n (FVB) and B6 mice deficient for PECAM to identify the gene or genes responsible for this unique feature of B6 mice. We have identified a locus on murine chromosome 2 at approximately 35.8 Mb that is strongly associated (LOD score = 9.0) with inflammatory responses in the absence of PECAM.

Conclusions/Significance

These data potentiate further study of the diapedesis machinery, as well as potential identification of new components of this machinery. As such, this study is an important step to better understanding the processes of inflammation.

Adiponectin deficiency promotes endothelial activation and profoundly exacerbates sepsis-related mortality

Sepsis is a multifactorial, and often fatal, disorder typically characterized by widespread inflammation and immune activation with resultant endothelial activation. In the present study, we postulated that the adipokine adiponectin serves as a critical modulator of survival and endothelial activation in sepsis. To this aim, we evaluated both loss-of-function (adiponectin gene-deficient mice) and subsequent gain-of-function (recombinant adiponectin reconstitution) strategies in two well-established inflammatory models, cecal ligation perforation (CLP) and thioglyocollate-induced peritonitis. Adipoq(-/-) mice, subjected to CLP, exhibited a profound ( approximately 8-fold) reduction in survival compared with their wild-type Adipoq(+/+) littermates after 48 h. Furthermore, compared with wild-type controls, thioglycollate challenge resulted in a markedly greater influx of peritoneal neutrophils in Adipoq(-/-) mice accompanied by an excess production of key chemoattractant cytokines (IL-12p70, TNFalpha, MCP-1, and IL-6) and upregulation of aortic endothelial adhesion molecule VCAM-1 and ICAM-1 expressions. Importantly, all of these effects were blunted by recombinant total adiponectin administration given 3 days prior to thioglycollate challenge. The protective effects of adiponectin were ascribed largely to higher-order adiponectin oligomers, since administration of recombinant C39A trimeric adiponectin did not attenuate endothelial adhesion molecule expression in thioglycollate-challenged Adipoq(-/-) mice. These data suggest a critical role of adiponectin as a modulator of survival and endothelial inflammation in experimental sepsis and a potential mechanistic link between adiposity and increased sepsis.

Application of a modified Haug and Lantzsch method for the rapid and accurate photometrical phytate determination in soybean, wheat, and maize meals

A modified version of the Haug and Lantzsch method for rapid photometrical phytate determination was applied for the analysis of phytate in soybean, wheat, and maize meals. In comparison to the original protocol, the amount of the toxic reagent thioglycolic acid is reduced substantially to minimize potential health risks for laboratory personnel. Different extraction conditions for soybean meal were tested, and boiling for at least 30 min was found to be necessary to remove an interfering compound in soybean meal extracts. Phytate contents determined according to the modified Haug and Lantzsch method did not differ from those obtained by measuring total precipitated phosphorus or by sensitive and specific high-performance ion chromatography. Applicability and accuracy of the modified method for phytate analysis in major feed substrates, including soy-based textured vegetable protein, were demonstrated.

Perkinsus chesapeaki in stout razor clams Tagelus plebeius from Delaware Bay

Perkinsus chesapeaki is reported from stout razor clams Tagelus plebeius in Delaware Bay, extending the known range of P. chesapeaki north of Chesapeake Bay. P. marinus, which causes dermo disease, is prevalent in cultured and wild oysters at this site, but was not detected in T. plebeius. Evidence for the presence of disseminated neoplasia, also reported from Chesapeake Bay, was equivocal. Although P. chesapeaki infections were associated with mortality events, light infection intensities and a general lack of histopathological evidence of disease limit inferences about a causal relationship. A comparison of Ray's fluid thioglycollate medium (RFTM)-based and PCR-based detection assays highlight differences in detection capabilities related to the quantity and type of tissue processed rather than assay sensitivity per se, a point that should be considered when surveying populations for disease prevalence. Investigators are further cautioned to use care when applying and interpreting diagnostic assays when used with novel species.

Galphai2 is required for chemokine-induced neutrophil arrest

Chemokines, including CXCL1, participate in neutrophil recruitment by triggering the activation of integrins, which leads to arrest from rolling. The downstream signaling pathways which lead to integrin activation and neutophil arrest following G-protein-coupled receptor engagement are incompletely understood. To test whether Galpha(i2) is involved, mouse neutrophils in their native whole blood were investigated in mouse cremaster postcapillary venules and in flow chambers coated with P-selectin, ICAM-1, and CXCL1. Gnai2(-/-) neutrophils showed significantly reduced CXCL1-induced arrest in vitro and in vivo. Similar results were obtained with leukotriene B(4) (LTB(4)). Lethally irradiated mice reconstituted with Gnai2(-/-) bone marrow showed a similar defect in chemoattractant-induced arrest as that of Gnai2(-/-) mice. In thioglycollate-induced peritonitis and lipopolysaccaride (LPS)-induced lung inflammation, chimeric mice lacking Galpha(i2) in hematopoietic cells showed about 50% reduced neutrophil recruitment similar to that seen in Gnai2(-/-) mice. These data show that neutrophil Galpha(i2) is necessary for chemokine-induced arrest, which is relevant for neutrophil recruitment to sites of acute inflammation.

The Fps/Fes kinase regulates leucocyte recruitment and extravasation during inflammation

Fps/Fes and Fer comprise a distinct subfamily of cytoplasmic protein-tyrosine kinases, and have both been implicated in the regulation of innate immunity. Previous studies showed that Fps/Fes-knockout mice were hypersensitive to systemic lipopolysaccharide (LPS) challenge, and Fer-deficient mice displayed enhanced recruitment of leucocytes in response to localized LPS challenge. We show here for the first time, a role for Fps in the regulation of leucocyte recruitment to areas of inflammation. Using the cremaster muscle intravital microscopy model, we observed increased leucocyte adherence to venules, and increased rates and degrees of transendothelial migration in Fps/Fes-knockout mice relative to wild-type animals subsequent to localized LPS challenge. There was also a decreased vessel wall shear rate in the post-capillary venules of LPS-challenged Fps/Fes-knockout mice, and an increase in neutrophil migration into the peritoneal cavity subsequent to thioglycollate challenge. Using flow cytometry to quantify the expression of surface molecules, we observed prolonged expression of the selectin ligand PSGL-1 on peripheral blood neutrophils from Fps/Fes-knockout mice stimulated ex vivo with LPS. These observations provide important insights into the observed in vivo behaviour of leucocytes in LPS-challenged Fps/Fes-knockout mice and provide evidence that the Fps/Fes kinase plays an important role in the innate immune response.

Furan-2-ylmethylene Thiazolidinediones as Novel, Potent, and Selective Inhibitors of Phosphoinositide 3-Kinase γ

Class I phosphoinositide 3-kinases (PI3Ks), in particular PI3Kgamma, have become attractive drug targets for inflammatory and autoimmune diseases. Here, we disclose a novel series of furan-2-ylmethylene thiazolidinediones as selective, ATP-competitive PI3Kgamma inhibitors. Structure-based design and X-ray crystallography of complexes formed by inhibitors bound to PI3Kgamma identified key pharmacophore features for potency and selectivity. An acidic NH group on the thiazolidinedione moiety and a hydroxy group on the furan-2-yl-phenyl part of the molecule play crucial roles in binding to PI3K and contribute to class IB PI3K selectivity. Compound 26 (AS-252424), a potent and selective small-molecule PI3Kgamma inhibitor emerging from these efforts, was further profiled in three different cellular PI3K assays and shown to be selective for class IB PI3K-mediated cellular effects. Oral administration of 26 in a mouse model of acute peritonitis led to a significant reduction of leukocyte recruitment.

Suppression of inflammation by low-dose methotrexate is mediated by adenosine A2A receptor but not A3 receptor activation in thioglycollate-induced peritonitis

Prior studies demonstrate that adenosine, acting at one or more of its receptors, mediates the anti-inflammatory effects of methotrexate in animal models of both acute and chronic inflammation. Both adenosine A2A and A3 receptors contribute to the anti-inflammatory effects of methotrexate treatment in the air pouch model of inflammation, and the regulation of inflammation by these two receptors differs at the cellular level. Because different factors may regulate inflammation at different sites we examined the effect of low-dose weekly methotrexate treatment (0.75 mg/kg/week) in a model of acute peritoneal inflammation in adenosine A2A receptor knockout mice and A3 receptor knockout mice and their wild-type littermates. Following intraperitoneal injection of thioglycollate there was no significant difference in the number or type of leukocytes, tumor necrosis factor alpha (TNF-alpha) and IL-10 levels that accumulated in the thioglycollate-induced peritoneal exudates in adenosine A2A knockout mice or wild-type control mice. In contrast, there were more leukocytes, TNF-alpha and IL-10 in the exudates of the adenosine A3 receptor-deficient mice. Low-dose, weekly methotrexate treatment increased the adenosine concentration in the peritoneal exudates of all mice studied, and reduced the leukocyte accumulation in the wild-type mice and A3 receptor knockout mice but not in the A2A receptor knockout mice. Methotrexate reduced exudate levels of TNF-alpha in the wild-type mice and A3 receptor knockout mice but not the A2A receptor knockout mice. More strikingly, IL-10, a critical regulator of peritoneal inflammation, was increased in the methotrexate-treated wild-type mice and A3 knockout mice but decreased in the A2A knockout mice. Dexamethasone, an agent that suppresses inflammation by a different mechanism, was similarly effective in wild-type mice, A2A mice and A3 knockout mice. These findings provide further evidence that adenosine is a potent regulator of inflammation that mediates the anti-inflammatory effects of methotrexate. Moreover, these data provide strong evidence that the anti-inflammatory effects of methotrexate and adenosine are mediated by different receptors in different inflammatory loci, an observation that may explain why inflammatory diseases of some organs but not of other organs respond to methotrexate therapy.