Expression of concern: Palladium supported on mixed-metal-organic framework (Co-Mn-MOF-74) for efficient catalytic oxidation of CO.

Expression of Concern for 'Palladium supported on mixed-metal-organic framework (Co-Mn-MOF-74) for efficient catalytic oxidation of CO' by Reda S. Salama et al., RSC Adv., 2021, 11, 4318-4326, https://doi.org/10.1039/D0RA09970H.

Carvacrol hinders the progression of hepatic fibrosis via targeting autotaxin and thioredoxin in thioacetamide-induced liver fibrosis in rat.

Fibrosis is a common outcome of nearly all chronic diseases of liver that results in changes of its functions which requires medical attention. The current research aims to investigate the potential anti-fibrotic efficacy of Carvacrol against thioacetamide (TAA)-induced liver fibrosis in male rats using Ursodeoxycholic acid (UDCA) as a reference anti-fibrotic product. Carvacrol (25 and 50 mg/kg) markedly declined TAA-increased serum liver enzymes; alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) as well as total bilirubin (TB) and direct bilirubin (DB) levels as well as increased levels of total protein (TP) and albumin. Carvacrol significantly reduced glutathione depletion (GSH), Nitric oxide (NOX) and malondialdehyde (MDA) accumulation in liver tissue. Additionally, its anti-oxidant effect brightened up via affecting markers of stress found in the cell as nuclear factor erythroid 2-related factor 2 (Nrf-2) where it still had high content and decreased Thioredoxin (Trx) level. The anti-inflammatory effect of Carvacrol was confirmed by decreasing nuclear factor kappa B (NF-κB), interleukin-1beta (IL-1ß) and inducible nitric oxide synthase (iNOS) contents. Carvacrol showed anti-fibrotic effect clarified by turning down fibrosis-related markers; TGF-ß1, matrix metalloproteinase-3 and 9 (MMP-3 and 9) and Autotaxin (ATX) contents. Furthermore, it decreased alpha smooth muscle actin (α-SMA) and caspase-3 immune-expression. The overall outcome of aforementioned markers results showed that Carvacrol suppresses the progression of liver fibrosis via its anti-oxidant, anti-inflammatory, anti-apoptotic effect and its ability in lowering Thioredoxin and Autotaxin; hence it can be categorized as a hepatoprotective natural substance.

Microwave-assisted synthesis of gold nanoparticles supported on Mn3O4 catalyst for low temperature CO oxidation.

In the present work, Mn3O4 was prepared by various methods and successfully loaded with metallic Au nanoparticles reduced by hydrazine hydrate using microwave irradiation (MWI) method. The surface morphology and composition of the prepared samples were characterized with X-ray diffraction (XRD), N2 adsorption-desorption, temperature programmed reduction (H2-TPR), transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). The experimental results showed that no significant changes in some textural and structural properties of the samples due to preparation method or Au nanoparticles deposition. While the surface composition and reducibility of the samples were greatly affected by preparation method and Au deposition. The CO oxidation reaction over the samples was selected as a model reaction to study the relation between surface properties of the samples and their catalytic performance. The results showed that a direct proportionality exists between the reducibility and the CO oxidation activity of catalysts. The kinetic study of the reaction showed that the reaction is first order. Moreover, the samples exhibited good stability in CO oxidation at 100% conversion for around 30 h under the reaction conditions.

Palladium supported on mixed-metal-organic framework (Co-Mn-MOF-74) for efficient catalytic oxidation of CO.

Successful monometallic and bimetallic metal-organic frameworks with different Co/Mn ratios have been synthesized under solvothermal conditions. The as-synthesized MOFs followed by deposition of Pd nanoparticles with 0.5 to 7 wt%. The XRD, BET, SEM, TEM, EDAX and FT-IR characterization results reveal that bimetallic MOFs and Pd nanoparticles were finely dispersed on the prepared MOFs surfaces. XRD results confirm the formation of the desire MOFs and show the high degree of dispersion of Pd nanoparticles. TEM images show that Pd nanoparticles are nano-sized with almost uniform shape. EDAX shows that Pd nanoparticles successfully loaded on Co0.5-Mn0.5-MOF-74 catalyst. CO oxidation as a model reaction was then used to assess the catalytic performance of the prepared catalysts. The catalytic activity results show enhancement in the catalytic activities of monometallic MOFs after introducing another metal in the same framework and show an excellent improvement in CO conversion after loading with Pd nanoparticles. Furthermore, the samples that contain Pd nanoparticles exhibits higher catalytic activities which raised with increasing the content of Pd nanoparticles.

Nano-MOFs as targeted drug delivery agents to combat antibiotic-resistant bacterial infections.

The drug resistance of bacteria is a significant threat to human civilization while the action of antibiotics against drug-resistant bacteria is severely limited owing to the hydrophobic nature of drug molecules, which unquestionably inhibit its permanency for clinical applications. The antibacterial action of nanomaterials offers major modalities to combat drug resistance of bacteria. The current work reports the use of nano-metal-organic frameworks encapsulating drug molecules to enhance its antibacterial activity against model drug-resistant bacteria and biofilm of the bacteria. We have attached rifampicin (RF), a well-documented antituberculosis drug with tremendous pharmacological significance, into the pore surface of zeolitic imidazolate framework 8 (ZIF8) by a simple synthetic procedure. The synthesized ZIF8 has been characterized using the X-ray diffraction (XRD) method before and after drug encapsulation. The electron microscopic strategies such as scanning electron microscope and transmission electron microscope methods were performed to characterize the binding between ZIF8 and RF. We have also performed picosecond-resolved fluorescence spectroscopy to validate the formation of the ZIF8-RF nanohybrids (NHs). The drug release profile experiment demonstrates that ZIF8-RF depicts pH-responsive drug delivery and is ideal for targeting bacterial disease corresponding to its inherent acidic nature. Most remarkably, ZIF8-RF gives enhanced antibacterial activity against methicillin-resistant Staphylococcus aureus bacteria and also prompts entire damage of structurally robust bacterial biofilms. Overall, the present study depicts a detailed physical insight for manufactured antibiotic-encapsulated NHs presenting tremendous antimicrobial activity that can be beneficial for manifold practical applications.

Prevalence of Salmonella and E. coli in neonatal diarrheic calves.

Neonatal calf diarrhea remains one of the most important problems faced by livestock, causing great economic losses. This study investigated the prevalence of Salmonella and Escherichia coli, especially enterotoxigenic E. coli (ETEC), in diarrheic calves. Fecal samples were collected from 127 diarrheic calves up to 3 months of age at 12 farms from different governorates in Egypt. 119 bacterial isolates (93.7%) were recovered and the prevalences of Salmonella and E. coli in diarrheic calves were 18.1% and 75.6%, respectively. Serotyping of Salmonella isolates revealed that S. Enteritidis and S. Typhimurium were the most prevalent serotypes, representing 60.9% and 30.4%, respectively, while S. Dublin was 8.7%. Serogrouping of E. coli isolates showed that 10 O-serogroups were obtained where O26 and O103 were the most prevalent (17.7% of each). Salmonella serotypes showed positive results with PCR test using oligonucleotide primer amplifying 521 bp fragment of invA gene of Salmonella while 70% of E. coli serogroups possessed ETEC virulent gene (K99). The in-vitro antibiotic sensitivity test indicated that Salmonella serotypes showed high sensitivity against enrofloxacin, spectinomycin and neomycin while E. coli isolates showed high sensitivities against marbofloxacin, spectinomycin and neomycin only.

Suppression of leopard moth (Lepidoptera: Cossidae) populations in olive trees in Egypt through mating disruption.

The leopard moth, Zeuzera pyrina (L.) (Lepidoptera: Cossidae), is a damaging pest for many fruit trees (e.g., apple [Malus spp.], pear [Pyrus spp.] peach [Prunus spp.], and olive [Olea]). Recently, it caused serious yield losses in newly established olive orchards in Egypt, including the death of young trees. Chemical and biological control have shown limited efficiency against this pest. Field tests were conducted in 2005 and 2006 to evaluate mating disruption (MD) for the control of the leopard moth, on heavily infested, densely planted olive plots (336 trees per ha). The binary blend of the pheromone components (E,Z)-2,13-octadecenyl acetate and (E,Z)-3,13-octadecenyl acetate (95:5) was dispensed from polyethylene vials. Efficacy was measured considering reduction of catches in pheromone traps, reduction of active galleries of leopard moth per tree and fruit yield in the pheromone-treated plots (MD) compared with control plots (CO). Male captures in MD plots were reduced by 89.3% in 2005 and 82.9% in 2006, during a trapping period of 14 and 13 wk, respectively. Application of MD over two consecutive years progressively reduced the number of active galleries per tree in the third year where no sex pheromone was applied. In all years, larval galleries outnumbered moth captures. Fruit yield from trees where sex pheromone had been applied in 2005 and 2006 increased significantly in 2006 (98.8 +/- 2.9 kg per tree) and 2007 (23 +/- 1.3 kg per tree) compared with control ones (61.0 +/- 3.9 and 10.0 +/- 0.6 kg per tree, respectively). Mating disruption shows promising for suppressing leopard moth infestation in olives.

Comparative analysis of the sialic acid binding activity and the tropism for the respiratory epithelium of four different strains of avian infectious bronchitis virus.

Avian infectious bronchitis virus (IBV) is a major pathogen in commercial poultry flocks. We recently demonstrated that sialic acid serves as a receptor determinant for IBV on the tracheal epithelium. Here we compared the IBV strains Beaudette, 4/91, Italy02, and QX for their sialic acid-binding properties. We demonstrate that sialic acid binding is important for the infection of primary chicken kidney cells and the tracheal epithelium by all four strains. There were only slight differences between the four strains, indicating the universal usage of sialic acids as receptor determinants by IBV. In addition, we analysed the primary target cells in the respiratory epithelium of the four different strains and found that all of them infected ciliated cells and goblet cells.

Comparative pharmacokinetics of ivermectin alone and a novel formulation of ivermectin and rafoxanide in calves and sheep.

This study investigated the comparative serum disposition kinetics of ivermectin (IVM) after a single subcutaneous dose of 200 microg/kg body weight of IVM alone or in combination with an anthelmintic consisting of ivermectin and rafoxanide (200 microg/kg of IVM and 2.5 mg/kg rafoxanide) for use in calves and sheep. The IVM concentrations in serum samples were analyzed by high-performance liquid chromatography with fluorescence detection. In sheep serum, rafoxanide induced a rapid absorption of IVM when given in combined form manifested by a shorter absorption half-life time of IVM by 68.49% when given in combination as compared with IVM when given alone. In addition, there is an increase in the value of the area under the concentration curve (AUC) by 15.48% while the value of elimination rate constant was decreased by 38.2% and significantly increased the half-life time of elimination from 2.04 days for IVM alone to 3.3 days when given in combination with rafoxanide. In calves serum, the mean t1/2ab for IVM/rafoxanide was 0.131 days and for the control formulation 0.16 days, and t1/2el was 5.78 and 4.95, respectively. IVM Cmax for IVM/rafoxanide was 22.4 ng/ml and for the control formulation 19.1 ng/ml. T (max) values were 0.99 and 1.12 days, and the mean AUC values were 188.9 and 165.4 ng/ml/day. The difference in Cmax, AUC, Kab, K el, and t1/2el was significant. However, there was no statistical difference between the Tmax and t1/2ab. These findings revealed that the combination of rafoxanide with IVM in sheep and calves increased the absorption of IVM and delayed its elimination.

Optimized conventional synthesis of "RGD" and "RGDS" peptides and their sarcosine mimics as integrin GP IIb/IIIa antagonists.

Synthetic arginyl-glycyl- alpha-aspartyl "RGD" and arginyl-glycyl- alpha-aspartyl-serinyl "RGDS" peptide sequences, which are originally located in matrix proteins, are confirmed to be as versatile integrin GP IIb/IIIa antagonists. Since integrins, as cell surface glycoprotein receptors are implicated in several physiological mechanisms, these peptides are recently specially considered in the design of new therapeutics. Replacing glycine by sarcosine, as its more lipophilic isomer, in RGD peptides seemed, accordingly, interesting in revealing some structural/biological activity relationships. To render "RGD" peptides more conveniently available, an ameliorated quasi-gram yield conventional synthesis in solution of the parent "RGD" and "RGDS" [8, Scheme 1A & 15, Scheme 1B] and their sarcosine analogues, [8', Scheme 1A & 15', Scheme 1B] respectively, is herein described.A compilation of the mild hydrogenolysis removable Z and NO(2) groups and/or the acidiolytic removable Boc group were manipulated for the amino temporary protecting steps. Both the DCCI/HOBt and MA methodologies served well as peptide coupling methods.

Synthesis and properties of new substituted 1,2,4-triazoles: potential antitumor agents.

Cycloaddition of the reactive intermediates 4 with 1-(cyanomethyl)benzotriazole (5) and its N-2 isomer 9 furnished, after spontaneous rearrangements, the 1,2,4-triazole derivatives 8 and 10. Analogously, reaction of 4 with ethyl cyanoacetate lead to the 1,3,5-trisubstituted 1,2,4-triazoles 12, which gave on treatment with hydrazine the corresponding hydrazides 13. Treatment of 13d with galactose or phenyl isothiocayanate gave the 1-D-galactose-acylhydrazone 14 and the 1,2,4-triazole derivative 15, respectively. Compounds 8c; 10b,c; 13a,c and 14 were selected for the antitumor screening, whereby 8c, 13a, and 13c showed remarkable activity against leukemia, ovarian, renal and lung cancers (8c with Gl(50) of 0.70 microM, 0.07 microM against leukemia (CCRF-CEM and RPMI-8226), 0.02 microM against ovarian (OVCAR-3) and 0.60 microM against renal (CARKI-1) and lung cancers, respectively).

Attachment of some internal laryngeal muscles at the base of the arytenoid cartilage.

The attachments of the lateral cricoarytenoid muscle, thyroarytenoid muscle and interarytenoid muscle at the base of the arytenoid cartilage were studied in six adult larynges. Fresh specimens were treated by the acetylthiocholine method, sections were made with a freezing microtome and stained with Van Gieson stain. The muscle fibres could thus be traced to their fibrous tendinous attachments. The extent of attachment of each muscle at the base of the arytenoid was traced and its relationship to the maximum concavity of the arytenoid articular facet was computed. The lateral cricoarytenoid muscle attachment extends anteromedially from the muscular process but falls short of the anterior border with a variation of 5,800M-7,800M. These variations are statistically significant. The thyroarytenoid and interarytenoid muscles' attachments show similar variations as described and discussed. The interpretation of these results is discussed and conclusions are drawn as regards the influence of these variations on the function of the glottis.

Intrinsic innervation of the oesophagus in dogs with special reference to the presence of muscle spindles.

The study of the intrinsic innervation of the oesophagus in dogs revealed the presence of capsulated ganglia and scattered neurons in the upper and lower thirds of the organ. The cells were either oval or pyriform with multiple dendrites and ill-defined capsules of pericellular satellites. Furthermore, muscle spindles were detected amidst the obliquely set muscle fibres of the oesophageal muscular coat. Simple motor and plates supplied the striated extrafusal muscle fibres. The submucous nerve plexus contained no ganglia. Its nerve fibres extended to form periacinar and intra-acinar axons to the oesophageal submucous glands. Subjacent to the mucosa, the subepithelial nerve plexus gave intraepithelial free terminals that penetrated the basement membrane to end within the stratified epithelium just beneath its cornified layer.

Experimental studies on the afferent innervation of the cricothyroid muscle in dogs.

The cricothyroid muscle in dogs received branches from two independent nerves, namely the external ramus of the cranial laryngeal nerve and the pharyngeal branch of the vagus. Classical spindles are infrequent in the muscle. Atypical forms of sensory endings were identified. Two end-plates were frequently met with on a single extrafusal fibre. Sectioning of the external ramus of the cranial laryngeal nerve was followed by degeneration of spindles. Intact axons detected up to 6 months after operation are probably derived from the pharyngeal branch of the vagus. Chromatolytic changes occurred in the ipsilateral dorsal vagal nucleus and the capsulated ganglion at the entry of the nerve into the muscle. Chromatolysis occurred in the intramuscular ganglion cell rows and in neurons of the ipsilateral nodose ganglion. Morphological alterations were more pronounced in the ipsilateral medial column of the nucleus ambiguus. No changes were observed in the somata of the mesencephalic nucleus.