Antioxidant Properties of Teucrium polium Extract Contribute to Neurochemical and Brain Structural Modulations in Nicotine-Induced Mice.

INTRODUCTION: Tobacco use is a major global health issue linked to psychiatric illnesses and high mortality rates. Nicotine, the primary compound absorbed during smoking, causes harm to various organs, particularly the brain. The current study examined the modulatory effect of Teucrium polium extract (TPE) on nicotine-induced biochemical and histological changes in the brains of mice. METHODS: Twenty-four mice were divided into four groups and were treated for three weeks. Group one was the control; Group two received 100 mg/kg TPE orally; Group three was subcutaneously injected with 2.5 mg/kg nicotine, and Group four received both nicotine and TPE. RESULTS: The brain tissue of the nicotine-induced group showed histopathological alterations and oxidative stress as indicated by increased lipid peroxidation and nitric oxide levels concomitant with decreased glutathione content and superoxide dismutase activity. DNA fragmentation was also detected by comet assay. Treatment with TPE significantly decreased oxidative stress and DNA fragmentation while increasing antioxidant biomarkers. Histopathological changes were also diminished. CONCLUSION: Through the antioxidant activity of TPE, it protected against nicotine-induced neurotoxicity in mice by impacting oxidative stress, DNA fragmentation, and brain histopathological changes.

Assessing pharmacokinetics and drug-drug interactions of the combination therapy of myelofibrosis with ruxolitinib and lenalidomide by a new eco-friendly HPLC method for their simultaneous determination in plasma.

Ruxolitinib (RUX), a Janus kinase 2 (JAK2) inhibitor, and lenalidomide (LEN), an immunomodulatory agent, have recently been proposed as a combined treatment for myelofibrosis (MF). This combination has demonstrated improved efficacy, safety, and tolerability compared to monotherapy. To further refine these findings, an efficient analytical tool is needed to simultaneously determine RUX and LEN concentrations in blood plasma. This tool would enable the study of their pharmacokinetics, drug-drug interactions, and therapeutic monitoring during MF therapy. Unfortunately, such a method has not been existed in the literature. This study presents the first HPLC method with UV detection for the simultaneous quantitation of RUX and LEN in plasma. The method was validated according to the ICH guidelines for bioanalytical method validation. It exhibited linearity in the concentration ranges of 10 to 3150 ng mL- 1 for RUX and 80 to 5200 ng mL- 1 for LEN. The limits of quantitation were determined to be 25 and 90 ng mL- 1 for RUX and LEN, respectively. All other validation parameters were satisfactory. The HPLC-UV method was successfully employed to study the pharmacokinetics and drug-drug interactions of RUX and LEN in rats following oral administration of single doses. The results demonstrated that the pharmacokinetics of both drugs were changed substantially by their coadministration. LEN exhibited synergistic effects on the maximum plasma concentration (Cmax) and total bioavailability of RUX, meanwhile it exhibited diminishing effect on the values of volume of distribution (Vd) and clearance (CL). Additionally, RUX decreased the Cmax and total bioavailability of LEN, meanwhile it increased its Vd and CL. These data suggest that the use of RUX, as a combination with LEN, is a better therapeutic approach for MF, compared with RUX as a monotherapy. The effects of LEN on the pharmacokinetics of RUX should be considered and can be useful in determining the appropriate RUX dosage and dosing regimen to achieve the desired therapeutic effect when used as a combination therapy with LEN. The method's environmental friendliness was confirmed through three comprehensive tools. This method represents a valuable tool for determining the appropriate dosage and dosing regimen of RUX in combination therapy with LEN to achieve the desired therapeutic effect. Furthermore, it can aid in predicting drug distribution in different patients and assessing the drug accumulation or insufficient drug levels in specific body compartments.

Decoding the Neurodevelopment and Seizure Puzzle: A Pediatric Case of DYRK1A Gene Mutation and Autosomal Dominant Mental Retardation Type 7.

Autosomal Dominant Mental Retardation Type 7 is a disorder caused by pathogenic variants in the DYRK1A gene. Clinical features associated with this gene mutation include focal dysmorphism, developmental delay, and epilepsy. In this report, we present a case of an 8-year-old boy with a DYRK1A gene mutation, whose clinical manifestations underscore the rarity and clinical challenges of this genetic condition. The patient is a known case of global developmental delay with intractable epilepsy on multiple anti-epileptic medications. Upon examination, the patient showed delayed developmental milestones, hypotonia with brisk deep tendon reflexes, as well as dysmorphic features in the form of microcephaly, deep-set eyes, prominent ears, and a short nose. MRI was done, and findings were suggestive of a DYRK1A gene mutation. The diagnosis was later confirmed by Whole Exome Sequencing (WES). Our report aims to contribute to the growing knowledge about DYRK1A mutations, facilitating a better understanding of the associated clinical features and implications for patient care.

The anti­hepatitis B virus activity of sea buckthorn is attributed to quercetin, kaempferol and isorhamnetin.

The present study assessed the in vitro anti-hepatitis B virus (HBV) effects of cold-adapted sea buckthorn (Hippophae rhamnoides). Sea buckthorn leaf ethanol extracts subjected to chloroform (SB-Chl), ethyl acetate (SB-Eac), n-butanol (SB-But) and aqueous (SB-Aqu) fractionation were first examined (MTT assay) for their toxic effects on HepG2 cells. While SB-Chl (IC50, 32.58 µg/ml) exhibited high cytotoxicity, SB-Eac, SB-But SB-Aqu were non-toxic at up to 150 µg/ml. High performance liquid chromatography analysis led to the identification of the anti-HBV active flavonols, quercetin (93.09 µg/g), kaempferol (44.19 µg/g) and isorhamnetin (138.75 µg/g) in the extract. The analysis of the anti-HBV effects of SB-Eac, SB-But and SB-Aqu (50 µg/ml, each) on HepG2.2.15 cells revealed the marked inhibition of HBsAg and HBeAg expression levels. At the concentration of 10 µg/ml, quercetin and kaempferol exerted potent inhibitory effects on HBsAg (60.5 and 62.3%, respectively) and HBeAg synthesis (64.4 and 60.2%, respectively), as compared to isorhamnetin (30.5 and 28.4%, respectively). The HBV-polymerase inhibitor drug, lamivudine (2 µM), inhibited HBsAg and HBeAg expression by 87.4 and 83.5%, respectively. The data were in good agreement with a previous in vitro and in silico molecular docking analysis performed by the authors where quercetin, kaempferol and lamivudine had formed stable complexes with HBV-polymerase binding-pocket amino acids. On the whole, to the best of our knowledge, the present study provides the first report of the anti-HBV therapeutic potential of sea buckthorn, attributed to quercetin, kaempferol and isorhamnetin.

Abdominoplasty Panniculus as a Source for Human Acellular Dermis: A Preliminary Report.

BACKGROUND: In extensive deep dermal burn injuries, split-thickness skin graft (STSG) has been the most preferred treatment option for resurfacing burn wounds. A thick split-thickness skin graft is ideal for preventing graft contracture but is associated with delayed donor healing and the lack of adequate donor skin. When applied with STSG, the dermal substitutes offer better-reconstructed skin than STSG alone. Human-derived acellular dermal matrix (HADM) obtained from cadaver skin is a dermal equivalent with good clinical outcomes. However, high cost and limited cadaver donor skin availability limit its clinical utility. Developing a low-cost preparation method and finding an alternate source of human donated skin can help reduce the cost. The objective of this study was to explore the feasibility of making HADM from abdominoplasty panniculus skin. METHODS: Skin samples were collected from the abdominoplasty panniculus of ten eligible donors with their informed consent. A combination of low-cost reagents-sodium chloride and hypotonic solution (water for injection) was used for decellularizing the skin. Characterization of the prepared Acellular Dermis Matrix prototype was done. RESULTS: The skin was deepidermized with one molar NaCl treatment at 37 °C for 24 h. The deepidermized dermis became acellular with hypotonic solution treatment at 4 °C for two weeks. The hematoxylin and eosin staining and cytotoxicity test confirmed the acellularity and non-cytotoxicity of the prepared HADM prototype. The HADM prototype also facilitated the formation of neo-epithelium in the 3D cell co-culture model. CONCLUSION: This study confirms that abdominoplasty panniculus can be a viable alternative for HADM preparation. Further characterization studies are required to prove the concept.

Response Surface Methodology (RSM)-Based Optimization of Ultrasound-Assisted Extraction of Sennoside A, Sennoside B, Aloe-Emodin, Emodin, and Chrysophanol from Senna alexandrina (Aerial Parts): HPLC-UV and Antioxidant Analysis.

In this study, ultrasound-assisted extraction conditions were optimized to maximize the yields of sennoside A, sennoside B, aloe-emodin, emodin, and chrysophanol from S. alexandrina (aerial parts). The three UAE factors, extraction temperature (S1), extraction time (S2), and liquid to solid ratio (S3), were optimized using response surface methodology (RSM). A Box-Behnken design was used for experimental design and phytoconstituent analysis was performed using high-performance liquid chromatography-UV. The optimal extraction conditions were found to be a 64.2 °C extraction temperature, 52.1 min extraction time, and 25.2 mL/g liquid to solid ratio. The experimental values of sennoside A, sennoside B, aloe-emodin, emodin, and chrysophanol (2.237, 12.792, 2.457, 0.261, and 1.529%, respectively) agreed with those predicted (2.152, 12.031, 2.331, 0.214, and 1.411%, respectively) by RSM models, thus demonstrating the appropriateness of the model used and the accomplishment of RSM in optimizing the extraction conditions. Excellent antioxidant properties were exhibited by S. alexandrina methanol extract obtained using the optimized extraction conditions with a DPPH assay (IC50 = 59.7 ± 1.93, µg/mL) and ABTS method (47.2 ± 1.40, µg/mL) compared to standard ascorbic acid.

Nephroprotective effect of persimmon leaves (Diospyros kaki L.f.) against CCl4-induced renal toxicity in Swiss Albino rats.

Diospyros kaki L.f. fruit and leaves are traditionally used for the treatment of hypertension, angina, internal hemorrhage, antithrombotic and anti-inflammatory effects.In the current study, the protective effects of ethyl acetate (Per-1), n-butanol (Per-2), and aqueous (Per-3) fractions of Diospyros kaki leaves against carbon tetrachloride (CCl4) induced nephrotoxicity in Swiss albino rats were tested. Animal were divided into nine groups; each group consists of six animals. The groups were : group I was untreated and kept as control, group II was treated with CCl4 only, group III (silymarin with CCl4); group IV (Per-1 100 mg/kg with CCl4);group V (Per-1 200 mg/kg with CCl4); group VI (Per-2 100 mg/kg with CCl4); group VII (Per-2 200 mg/kg with CCl4); group VIII (Per-3 100 mg/kg with CCl4); and group IX (Per-3 200 mg/kg with CCl4). Silymarin was used as standard drug. All tested fractions were found active (except Per-1 at low dose of 100 mg/kg) with significant value (p < 0.001) compared to CCl4 only group. Serum creatinine, malondialdehyde (MDA), and uric acid were significantly (p < 0.001) lowered in group VII-IX as compared to CCl4 only group. Similarly, total protein (TP) and non-protein sulfhydryls(NP-SH) level in kidney tissues were significantly (p < 0.001) elevated in the same groups compared to CCl4 only group. Further to check the cardio-protective potential, biochemical parameters such as LDH, creatine kinase, TP, MDA, and NP-SH levels in myocardial tissues were also estimated.These findings confirmed that the n-butanol and aqueous fractions are active and recommended for further bioactive phytoconstituents screening. Repeated column chromatography on silica gel G and sephadex-LH-20 of the active n-butanol fraction, four flavonoids were isolated. Based on the spectroscopic NMR data, compounds were identified as kaempferol (1), quercetin (2), astragalin (3), and rutin (4).

Oral Beta-blocker in Problematic Infantile Hemangioma.

One of the most common benign vascular endothelial tumors is infantile hemangioma. These lesions are commonly found in the head and neck, and sometimes it is a challenge to decide the method of treatment if the lesions are problematic hemangiomas, interfering with function or aesthetic appearance. This study reports a case of girl aged 3 years, 7 months, diagnosed with periorbital infantile hemangioma that was successfully treated with oral propranolol in specific doses and gradual tapering off dose. The patient had marked involution of the lesion with no significant side effects after starting her treatment at the age of 4 months, for a total of 13 months with no reported rebound growth after almost 2 years since the termination of treatment. Oral beta-blockers can be used safely in treatment of problematic infantile hemangioma as a single modality, without any surgical intervention.

Impact of Different Extraction Methods on Furanosesquiterpenoids Content and Antibacterial Activity of Commiphora myrrha Resin.

The oleo-gum-resin of Commiphora myrrha is one of the most known natural antimicrobial agents, mainly due to its furanosesquiterpenes. A validated method based on sample extraction by matrix solid-phase dispersion (MSPD) followed by high-performance column chromatography (HPLC) determination is applied to analyze two furanosesquiterpenoids, namely, 2-methoxyfuranodiene (CM-1) and 2-acetoxyfuranodiene (CM-2), existing in C. myrrha. The trial parameters that controlled the extraction prospective were studied and optimized. These include the nature of dispersant, mass ratio of sample to the dispersant, and the volume of elution solvent. A comparative antimicrobial study that used the Minimum Inhibitory Concentration Assay (MIC) method between MSPD, ultrasonic, and Soxhlet of myrrh extracts was also conducted. The optimal MSPD parameters used were (i) 15 mL of methanol applied as elution solvent; (ii) silica gel/sample mass at a 2 : 1 ratio; and (iii) a dispersing sorbent selected as silica gel. Technique retrievals were regulated from 96.87% to 100.54%, with relative standard deviations (RSDs) from 1.24% to 4.45%. Commiphora myrrha-MSPD (CM-MSPD) extract showed the highest antibacterial activity against gram-positive and gram-negative bacteria (156.25 µg/mL and 312.5 µg/mL, respectively) and antifungal activity (156.25 µg/mL). Yields acquired through the MSPD technique were larger than yields from other extraction techniques (sonication and traditional reflux extraction methods) with less consumption of time, sample, and solvent. The mode of antibacterial action of CM-1 and CM-2 was elucidated by performing molecular docking with bacterial DNA gyrase. Both the compounds interacted with key residues of DNA gyrase.

Charge-Transfer Complex of Linifanib with 2,3-dichloro-3,5-dicyano-1,4-benzoquinone: Synthesis, Spectroscopic Characterization, Computational Molecular Modelling and Application in the Development of Novel 96-microwell Spectrophotometric Assay.

BACKGROUND: Linifanib (LFB) is a multi-targeted receptor tyrosine kinase inhibitor used in the treatment of hepatocellular carcinoma and other types of cancer. The charge-transfer (CT) interaction of LFB is important in studying its receptor binding mechanisms and useful in the development of a reliable CT-based spectrophotometric assay for LFB in its pharmaceutical formulation to assure its therapeutic benefits. PURPOSE: The aim of this study was to investigate the CT reaction of LFB with 2,3-dichloro-3,5-dicyano-1,4-benzoquinone (DDQ) and its application in the development of a novel 96-microwell spectrophotometric assay for LFB. METHODS: The reaction was investigated, its conditions were optimized, the physicochemical and constants of the CT complex and stoichiometric ratio of the complex were determined. The solid-state LFB-DDQ complex was synthesized and its structure was analyzed by UV-visible, FT-IR, and 1H-NMR spectroscopic techniques, and also by the computational molecular modeling. The reaction was employed in the development of a novel 96-microwell spectrophotometric assay for LFB. RESULTS: The reaction resulted in the formation of a red-colored product, and the spectrophotometric investigations confirmed that the reaction had a CT nature. The molar absorptivity of the complex was linearly correlated with the dielectric constant and polarity index of the solvent; the correlation coefficients were 0.9526 and 0.9459, respectively. The stoichiometric ratio of LFB:DDQ was 1:2. The spectroscopic and computational data confirmed the sites of interaction on the LFB molecule, and accordingly, the reaction mechanism was postulated. The reaction was utilized in the development of the first 96-microwell spectrophotometric assay for LFB. The assay limits of detection and quantitation were 1.31 and 3.96 µg/well, respectively. The assay was successfully applied to the analysis of LFB in its bulk and tablets with high accuracy and precision. CONCLUSION: The assay is simple, rapid, accurate, eco-friendly as it consumes low volumes of organic solvent, and has high analysis throughput.

Darunavir: A comprehensive profile.

Darunavir: (3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-yl [(2S,3R)-4-{[(4-aminophenyl)sulfonyl] (isobutyl)amino}-3-hydroxy-1-phenyl-2-butanyl]carbamate is a synthetic non-peptide protease inhibitor. On June 2006, it was first approved by the Food and Drug administration (FDA) for treatment of resistant type-1 of the human immunodeficiency virus (HIV). In July 2016, the FDA expanded the approval for use of darunavir in pregnant women with HIV infection. Darunavir prevents the replication of HIV virus by inhibiting the catalytic activity of the HIV-1 protease enzyme, and selectively inhibits the cleavage of HIV encoded Gag-Pol polyproteins in virus-infected cells, which prevents the formation of mature infectious virus particles. Darunavir is unique among currently available protease inhibitors because it maintains antiretroviral activity against a variety of multidrug-resistant HIV strains. This article discusses, by a critical extensive review of the literature, the description of darunavir in terms of its names, formulae, elemental composition, appearance, and use in the treatment of HIV-infected patients. The article also discusses the methods for preparation of darunavir, its physical-chemical properties, analytical methods for its determination, pharmacological properties, and dosing information.

In Vitro Antioxidant, Cytotoxic Activities, and Phenolic Profile of Senecio glaucus from Saudi Arabia.

Current treatments for complex diseases have remarkable side effects that negatively impact patients' quality of life. Thus, natural compounds with fewer side effects represent a promising source for safe drugs. The genus Senecio is widely used in folk medicine due to its various pharmacological properties. In the present study, the total phenolic content of Senecio glaucus, which is grown in Saudi Arabia, was assessed using the Folin-Ciocalteau colorimetric method. Scavenging DPPH and ABTS assays were utilized to determine the antioxidant properties of S. glaucus fractions, and MTT assay was used to screen the cytotoxic activity of S. glaucus against various cancer cells. In addition, HPLC-UV was utilized to detect the presence of two phenolic acids, namely, vanillic acid (VA) and gallic acid (GA). Among all fractions tested, S. glaucus chloroform fraction (SGCF) yielded the highest value (125.3 mg·GA/g) in terms of total phenolic content. SGCF also exhibited the highest scavenging activities (76.7 and 74.1%) on both DPPH and ABTS assays, respectively. Similarly, SGCF also possessed the most potent cytotoxic activity against the MCF-7 cell line, with an IC50 value of 41.8 µg/ml. The validated HPLC method confirmed the presence of VA (4.8 µg/mg DW) and GA (3.9 µg/mg DW) in SGCF. Overall, our data show that S. glaucus had antioxidant and cytotoxic properties. A developed validated HPLC method which could be helpful for quantifying phenolic compounds in S. glaucus was established.

Preparation and Characterization of Two Immunogens and Production of Polyclonal Antibody with High Affinity and Specificity for Darunavir.

Darunavir (DRV) is a potent antiviral drug used for treatment of infections with human immunodeficiency virus (HIV). Effective and safe treatment with DRV requires its therapeutic drug monitoring (TDM) in patient's plasma during therapy. To support TDM of DRV, a specific antibody with high affinity is required in order to develop a sensitive immunoassay for the accurate determination of DRV in plasma. In this study, two new and different immunogens were prepared and characterized. These immunogens were the DRV conjugates with keyhole limpet hemocyanin (KLH) protein. The first immunogen (DRV-KLH) was prepared by zero-length direct linking of DRV via its aromatic amino group with the tyrosine amino acid residues of KLH by diazotization/coupling reaction. The second immunogen (G-DRV-KLH) was prepared by conjugation of the N-glutaryl derivative of DRV (G-DRV) with KLH. The 5-carbon atoms-spacing G-DRV hapten was synthesized by reaction of DRV via its aromatic amino group with glutaric anhydride. The reaction was monitored by HPLC and the chemical structure of G-DRV was confirmed by mass, 1H-NMR, and 13C-NMR spectroscopic techniques. The hapten (G-DRV) was linked to the KLH protein by water-soluble 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) coupling procedure. The pertinence of the coupling reactions of haptens to protein was confirmed, and the immunogens were characterized by ultraviolet (UV) spectrophotometry. Both DRV-KLH and G-DRV-KLH were used for the immunization of animals and the animal's antiserum that showed the highest affinity was selected. The collected antiserum (polyclonal antibody) had very high affinity to DRV (IC50 value = 0.2 ng mL-1; defining IC50 as the DRV concentration that can inhibit antibody binding by 50% of its maximum binding) and high specificity to DRV among other drugs used in the combination therapy with DRV. Cumulative results from direct and competitive enzyme-linked immunosorbent assay (ELISA) using this polyclonal antibody proved that the immunogens were highly antigenic and elicited a specific polyclonal antibody. The produced polyclonal antibody is valuable for the development of highly sensitive and selective immunoassays for TDM of DRV.

Rapid and Sensitive Method for Extraction of Plicosepalus acacia with Determination of Its Main Polyphenolic Compounds Using Validated HPLC.

Matrix solid phase dispersion (MSPD) trailed by HPLC is a quick and fruitful technique utilized for fortitude of flavonoids such as Catechin, Kaempferol, Quercetin, and Rutin existing in P. acacia. The trial parameters that influenced the extraction potential (comprising the mass ratio of sample to the dispersant, nature of dispersant, and the nature of elution solvent and its volume) were examined and optimized. These MSPD optimized parameters regulated are as follows: 8 mL of methanol was utilized as elution solvent, silica gel/sample mass ration was selected to be 2 : 1, and dispersing sorbent was silica gel. The technique retrievals were regulated to be "from 96.87 to 100.54%" and the RSDs from 1.24 to 4.45%. The product of extract obtained by MSPD method was larger than that of other methods, i.e., sonication extraction or traditional reflux with lessened necessities on time, sample, and solvent.

Development of a highly sensitive ELISA for determination of darunavir in plasma samples using a polyclonal antibody with high affinity and specificity.

Aim: To support pharmacokinetic studies and therapeutic monitoring of darunavir (DRV), a highly sensitive ELISA was developed for the determination of DRV in plasma samples at picogram levels. Results: The assay LOD and LOQ were 15 and 30 pg ml-1, respectively. The working range of the assay was 20-2000 pg ml-1. Analytical recoveries of DRV from spiked plasma were in the ranges of 98.4-113.0 and 86.0-99.1% for intra-assay and inter-assay runs, respectively. The precision of the assay was satisfactory. Conclusion: The ELISA is characterized by high throughput and it is expected to significantly contribute to routine analysis of DRV in its pharmacokinetic studies and therapeutic monitoring.

Spectroscopic and molecular docking studies reveal binding characteristics of nazartinib (EGF816) to human serum albumin.

The interactions of novel anti-cancer therapeutic agents with the different plasma and tissue components, specifically serum albumins, have lately gained considerable attention due to the significant influence of such interactions on the pharmacokinetics and/or -dynamics of this important class of therapeutics. Nazartinib (EGF 816; NAZ) is a new anti-cancer candidate proposed as a third-generation epidermal growth factor receptor tyrosine kinase inhibitor that is being developed and clinically tested for the management of non-small cell lung cancer. The current study aimed to characterize the interaction between NAZ and human serum albumin (HSA) using experimental and theoretical approaches. Experimental results of fluorescence quenching of HSA induced by NAZ revealed the development of a statically formed complex between NAZ and HSA. Interpretation of the observed fluorescence data using Stern-Volmer, Lineweaver-Burk and double-log formulae resulted in binding constants for HSA-NAZ complex in the range of (2.34-2.81) × 104 M-1 over the studied temperatures. These computed values were further used to elucidate thermodynamic attributes of the interaction, which showed that NAZ spontaneously binds to HSA with a postulated electrostatic force-driven interaction. This was further verified by theoretical examination of the NAZ docking on the HSA surface that revealed an HSA-NAZ complex where NAZ is bound to HSA Sudlow site I driven by hydrogen bonding in addition to electrostatic forces in the form of pi-H bond. The HSA binding pocket for NAZ was shown to encompass ARG 257, ARG 222, LYS 199 and GLU 292 with a total binding energy of -25.59 kJ mol-1.

Ocular Trematodiasis Caused by the Avian Eye Fluke Philophthalmus in Southern Texas.

A trematode identified as a Philophthalmus sp was extracted from the bulbar conjunctiva of a patient in southern Texas with short-distance travel to Mexico. This parasite is very rarely reported from humans, and species identification is challenging. Aspects of diagnosis, zoonotic transmission, and unresolved questions about Philophthalmus spp are discussed.

Novel BTK inhibitor acalabrutinib (ACP-196) tightly binds to site I of the human serum albumin as observed by spectroscopic and computational studies.

Spectrofluorometric, UV-vis spectroscopic and theoretical tools were recruited to comprehend the interaction of acalabrutinib (ACP-196; ACLB) with human serum albumin (HSA). Fluorescence intensity determinations revealed that ACLB statically quenched the HSA-native fluorescence. Analysis of the observed fluorescence data resulting from the ACLB-HSA interaction presented binding constants in the range of 6.65-7.54 × 104 M-1 with the studied temperatures. Those constants showed steady decline with the rising temperatures that further signifies static interaction of the HSA and ACLB. Binding energetics were also interpreted using the fluorescence-recorded results that exhibited a spontaneous exothermic binding reaction with a negative change in Gibbs free energy as well as negative enthalpy and positive entropy changes. Those results suggested the involvement of electrostatic forces as discovered by further computational investigation. Those docking results verified that ACLB binds to domain IIA (site I) of the HSA as demonstrated experimentally by site markers displacement binding studies. Circular dichroism studies along with the synchronous and 3D fluorescence observations showed that ACL binding does not alter the HSA conformation.

Association between oral fluoroquinolone use and lateral canthal tendon rupture: case report.

It is well established and documented that fluoroquinolone use is associated with the development of tendinopathy. However, little is known about the possible effects of this class of antibiotics on the orbit. We present a case of lateral canthal tendon rupture that presented with an acute right lower eyelid ectropion in a young, renal compromised patient in the setting of recent fluoroquinolone use for pneumonia. Eye care clinicians need to be aware of the possible effects of fluoroquinolones on the eyelids.