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Background: Anomalous origin of left coronary artery from pulmonary artery is a very rare disease with incidence of one every 300,000 live births. It has a high mortality of 80% in the first year of life. This observational study summarized our experience using the technique of subclavian arterial bypass without the use of cardiopulmonary bypass (CPB) for treatment of this coronary anomaly in pediatric population. The study aims to revive an earlier technique, with modifications, as an alternative to the existing coronary translocation. Methods: From 2009 till 2015, six consecutive infants were operated by a single surgeon using subclavian artery to left coronary artery bypass done off pump, to establish a two coronary circulation. Results: Five patients had an improvement in their LV ejection fractions at the time of the last follow-up. Angiography done in two cases after 2 and 6 years after surgery revealed good flow in the left coronary artery and good growth in the length of subclavian artery. There was one surgical mortality in this series. Conclusions: The technique of off pump subclavian arterial bypass for anomalous origin of the left coronary artery from the pulmonary artery is a viable alternative to the existing standard technique of coronary translocation. It essentially eliminates extracorporeal circulatory support or a left heart bypass that may be needed after coronary translocation. Also, the advantage of avoiding CPB, both in economic terms and also the adverse effects related to use of bypass in this very sick hearts, cannot be disregarded.

In this paper, an analytical model is proposed to predict magnetic flux leakage (MFL) signals from the surface defects in ferromagnetic tubes. The analytical expression consists of elliptic integrals of first kind based on the magnetic dipole model. The radial (Bz) component of leakage fields is computed from the cylindrical holes in ferromagnetic tubes. The effectiveness of the model has been studied by analyzing MFL signals as a function of the defect parameters and lift-off. The model predicted results are verified with experimental results and a good agreement is observed between the analytical and the experimental results. This analytical expression could be used for quick prediction of MFL signals and also input data for defect reconstructions in inverse MFL problem.

Objective: To study growth and skeletal maturation in children with type 1 diabetes mellitus (T1DM). Methods: We prospectively studied the anthropometric data of 56 children with T1DM at our tertiary care teaching hospital. Height was re-measured at one year to assess height velocity. A plain radiograph of the left hand was obtained for assessment of skeletal maturation. Glycosylated haemoglobin and thyroid stimulating hormone were measured in all the patients. Results: Short stature [height standard deviation score (HtSDS)

Peptides are distinctive biomacromolecules that demonstrate potential cytotoxicity and diversified bioactivities against a variety of microorganisms including bacteria, mycobacteria, and fungi via their unique mechanisms of action. Among broad-ranging pharmacologically active peptides, natural marine-originated thiazole-based oligopeptides possess peculiar structural features along with a wide spectrum of exceptional and potent bioproperties. Because of their complex nature and size divergence, thiazole-based peptides (TBPs) bestow a pivotal chemical platform in drug discovery processes to generate competent scaffolds for regulating allosteric binding sites and peptide–peptide interactions. The present study dissertates on the natural reservoirs and exclusive structural components of marine-originated TBPs, with a special focus on their most pertinent pharmacological profiles, which may impart vital resources for the development of novel peptide-based therapeutic agents.

Prostate cancer (PCa) patients commonly experience clinical depression. Recent reports indicated that monoamine oxidase-A (MAO-A) levels elevate in PCa, and antidepressant MAO-Is show anti-PCa properties. In this work, we aimed to find potential drugs for PCa patients suffering from depression by establishing novel anti-PCa reversible monoamine oxidase-A inhibitors (MAO-AIs/RIMA); with an endeavor to understand their mechanism of action. In this investigation, twenty synthesized flavonoid derivatives, defined as KKR compounds were screened for their inhibitory potentials against human MAO-A and MAO-B isozymes. Meanwhile, the cytotoxic and antiproliferative effects were determined in three human PCa cell lines. MAO-A-kinetics, molecular docking, SAR, cell morphology, and cell migration were investigated for the most potent compounds. The screened KKRs inhibited MAO-A more potently than MAO-B, and non-toxically inhibited LNCaP cell proliferation more than the DU145 and PC3 cell lines, respectively. The results showed that the three top MAO-AI KKRs compounds (KKR11, KKR20, and KKR7 (IC50s 0.02–16 μM) overlapped with the top six antiproliferative KKRs against LNCaP (IC50s ~9.4 μM). While KKR21 (MAO-AI) and KKR2A (MAO-I) were ineffective against the PCa cells. Furthermore, KKR21 and KKR11 inhibited MAO-A competitively (Kis ≤ 7.4 nM). Molecular docking of the two compounds predicted shared hydrophobic and distinctive hydrophilic interactions—between the KKR molecule and MAO-A amino acid residues—to be responsible for their reversibility. The combined results and SAR observations indicated that the presence of specific active groups—such as chlorine and hydroxyl groups—are essential in certain MAO-AIs with anti-PCa effects. Additionally, MAO-A inhibition was found to be associated more with anti-PCa property than MAO-B. Distinctively, KKR11 [(E)-3-(3,4-dichlorophenyl)-1-(2-hydroxy-4,6-dimethoxyphenyl)prop-2-en-1-one] exhibited anti-metastatic effects on the DU145 cell line. The chlorine substitution groups might play vital roles in the KKR11 multiple actions. The obtained results indicated that the flavonoid derivative KKR11 could present a novel candidate for PCa patients with depression, through safe non-selective potent inhibition of MAOs.

P-glycoprotein (P-gp) is an ABC transporter that exports many amphipathic or hydrophobic compounds, including chemically and functionally dissimilar anticancer drugs, from cells. To understand the role of transmembrane helices (TMH) 1 and 7 in drug-binding and transport, we selected six residues from both TMH1 (V53, I59, I60, L65, M68 and F72) and TMH7 (V713, I719, I720, Q725, F728 and F732); and substituted them with alanine by gene synthesis to generate a variant termed "TMH1,7 mutant P-gp". The expression and function of TMH1,7 mutant P-gp with twelve mutations was characterized using the BacMam baculovirus-HeLa cell expression system. The expression and conformation of TMH1,7 mutant P-gp was not altered by the introduction of the twelve mutations, as confirmed by using the human P-gp-specific antibodies UIC2, MRK16 and 4E3. We tested 25 fluorescently-labeled substrates and found that only three substrates, NBD-cyclosporine A, Rhod-2-AM and X-Rhod-1-AM were transported by the TMH1,7 mutant. The basal ATPase activity of TMH1,7 mutant P-gp was lower (40-50%) compared to wild-type (WT) P-gp, despite similar level of expression. Although most of the substrates modulate ATPase activity of P-gp, the activity of TMH1,7 mutant transporter was not significantly modulated by any of the tested substrates. Docking of selected substrates in homology models showed comparable docking scores for the TMH1,7 mutant and WT P-gp, although the binding conformations were different. Both the ATPase assay and in silico docking analyses suggest that the interactions with residues in the drug-binding pocket are altered as a consequence of the mutations. We demonstrate that it is possible to generate a variant of P-gp with a loss of broad substrate specificity and propose that TMH1 and TMH7 play a critical role in the drug efflux function of this multidrug transporter.

Background: There is a paucity of observational data from India on initial catch up growth in hypothyroid children started on thyroxine replacement therapy. Methods: We retrospectively studied 44 children and adolescents (32 girls) with a diagnosis of primary hypothyroidism i.e., (thyrotropin > 15 µIU/mL and thyroxine < 55ng/mL). All were started on treatment with oral thyroxine. The dose was adjusted to maintain thyrotropin between 0.5-5 µIU/mL. Height was measured at baseline and at each follow-up visit and height standard deviation scores (HtSDS) were calculated. We studied the therapeutic benefit of thyroxine replacement therapy on growth in the initial couple of years of treatment. Results: Dose of thyroxine required to restore euthyroidism was 4.1±2.5 µg/kg body weight. The dose fell from 9.7±2.4 µg/kg body weight in infants to 3.0±1.5 µg/kg body weight in adolescence (p

The data described in this article pertain to the article by Kuchipudi et al. (2014) titled “Highly Pathogenic Avian Influenza Virus Infection in Chickens But Not Ducks Is Associated with Elevated Host Immune and Pro-inflammatory Responses” [1]. While infection of chickens with highly pathogenic avian influenza (HPAI) H5N1 virus subtypes often leads to 100% mortality within 1 to 2 days, infection of ducks in contrast causes mild or no clinical signs. The rapid onset of fatal disease in chickens, but with no evidence of severe clinical symptoms in ducks, suggests underlying differences in their innate immune mechanisms. We used Chicken Genechip microarrays (Affymetrix) to analyse the gene expression profiles of primary chicken and duck lung cells infected with a low pathogenic avian influenza (LPAI) H2N3 virus and two HPAI H5N1 virus subtypes to understand the molecular basis of host susceptibility and resistance in chickens and ducks. Here, we described the experimental design, quality control and analysis that were performed on the data set. The data are publicly available through the Gene Expression Omnibus (GEO)database with accession number GSE33389, and the analysis and interpretation of these data are included in Kuchipudi et al. (2014) [1].

Robotics is the science. In scientific words a "Robot" is an electromechanical arm device with a computer interface, a combination of electrical, mechanical, and computer engineering. It is a mechanical arm that performs tasks in Industries, space exploration, and science. One such idea was to make an automated arm - A robot - In laparoscopy to control the telescope-camera unit electromechanically and then with a computer interface using voice control. It took us 5 long years from 2004 to bring it to the level of obtaining a patent. That was the birth of the Swarup Robotic Arm (SWARM) which is the first and the only Indian contribution in the field of robotics in laparoscopy as a total voice controlled camera holding robotic arm developed without any support by industry or research institutes.

Changes in left coronary artery flow pattern in anomalous left coronary from pulmonary artery can provide valuable insight into pathology and natural history of disease. We wish to discuss a case with pre and post operative left coronary flow pattern with mid term follow up.

Melanoma is the most serious type of skin cancer and one of the most common cancers in the world. Advanced melanoma is often resistant to conventional therapies and has high potential for metastasis and low survival rates. Vemurafenib is a small molecule inhibitor of the BRAF serine-threonine kinase recently approved by the United States Food and Drug Administration to treat patients with metastatic and unresectable melanomas that carry an activating BRAF (V600E) mutation. Many clinical trials evaluating other therapeutic uses of vemurafenib are still ongoing. The ATP-binding cassette (ABC) transporters are membrane proteins with important physiological and pharmacological roles. Collectively, they transport and regulate levels of physiological substrates such as lipids, porphyrins and sterols. Some of them also remove xenobiotics and limit the oral bioavailability and distribution of many chemotherapeutics. The overexpression of three major ABC drug transporters is the most common mechanism for acquired resistance to anticancer drugs. In this review, we highlight some of the recent findings related to the effect of ABC drug transporters such as ABCB1 and ABCG2 on the oral bioavailability of vemurafenib, problems associated with treating melanoma brain metastases and the development of acquired resistance to vemurafenib in cancers harboring the BRAF (V600E) mutation.

Objective: The primary objective of this study was to evaluate the antihypertensive efficacy of the chlorthalidone and telmisartan combination in Indian hypertensive patients who remained uncontrolled after taking the hydrochlorothiazide and telmisartan combination. Methods: A total of 100 eligible patients were enrolled in this prospective, open label study. The patients were given telmisartan (40 mg) and chlorthalidone (12.5 mg), who had not achieved the target blood pressure (140/90 mmHg) despite taking the combination of telmisartan (40 mg) and hydrochlorothiazide (12.5 mg). The assessment was done at the end of 4 weeks and 8 weeks. Results: The mean SBP and DBP after taking telmisartan (40 mg) and hydrochlorothiazide (12.5 mg) were 154.88±9.57 (range 144 to 160) mmHg and 99.37±2.78 (range 92 to 106). At the end of 4 weeks of being on telmisartan (40 mg) and chlorthalidone (12.5 mg), the mean SBP and DBP were 145.56±5.12 (range 134 to 158) mmHg and 95.14±4.27 (range 84 to 100) mmHg. Significant falls in the SBP (5.32±2.64) and DBP (4.18±2.48) were noted at the end of the 4 week therapy. They were sustained at the end of 8 weeks also. The SBP target (

Atrial septal defect (ASD) with rheumatic mitral stenosis is popularly known as eponym of Lutembacher syndrome. Definitive treatment of Lutembacher syndrome has been under the purview of cardiothoracic surgeons but with changing times, transcatheter treatment has been possible. We present a case of 38-year-old female with Lutembacher syndrome treated transcatheterly. This case attests the feasibility of transcatheter treatment in selected group of patients of Lutembacher treatment.

In the present study, we have developed a green approach for the synthesis of silver nanoparticles (DSAgNPs) using aqueous extract of Durio zibethinus seed and determined its antibacterial, photocatalytic and cytotoxic effects. Surface plasmon resonance confirmed the formation of DSAgNPs with a maximum absorbance (λmax) of 420 nm. SEM and TEM images revealed DSAgNPs were spherical and rod shaped, with a size range of 20 nm and 75 nm. The zeta potential was found to be −15.41 mV. XRD and EDX analyses confirmed the nature and presence of Ag and AgCl. DSAgNPs showed considerable antibacterial activity, exhibited better cytotoxicity against brine shrimp, and shown better photocatalytic activity against methylene blue. Based on the present research work, it can be concluded that DSAgNPs could be used in the field of water treatment, pharmaceuticals, biomedicine, biosensor and nanotechnology in near future.

Background: Thyroid disorders are known to cause metabolic disturbances. Dyslipidemia, one of the important modifiable cardiovascular risk factors is known in patients with overt hypothyroidism (OHT) and is also reported in sub clinical hypothyroidism (SHT). Aims: To evaluate dyslipidemia, lipid ratios and atherogenic index in patients with OHT and SHT in comparison with healthy controls and between the hypothyroid patients. Material and Methods: The study included 36 patients with OHT, 36 patients with SHT and 39 euthyroid controls. OHT was diagnosed with thyroid stimulating hormone (TSH) level of >15 mU/L and thyroxine (T4)

ABSTRACT Objective: This study was to evaluate the levels of NT-proBNP in patients with myocarditis which occurred after a scorpion sting envenomation. Material and Methods: A total of 30 patients with scorpion sting envenomation and 21 patients with heart failure which was caused by cardiomyopathy, were prospectively studied. The data included the patient demographics, clinical features, echocardiography and the NT-proBNP levels. Results: An echocardiographic evidence of myocarditis with a left ventricular ejection fraction of less than 50%, was found in 22 patients. In all the 22 patients, NT-proBNP was significantly elevated. The NT-proBNP levels were very high in the patients with severe LV dysfunction. However, it was in the normal range in the patients without an evidence of myocarditis. The elevated NT-proBNP levels were correlated with the LV dysfunction and myocarditis. When they were compared with the patients with heart failure which was caused by cardiomyopathy, the NTproBNP levels were found to be significantly more elevated in scorpion sting myocarditis. Conclusions: The NT-proBNP levels were significantly elevated in myocarditis which occurred after a scorpion sting envenomation.

Hemolytic anemia following a mitral valve repair is a very rare complication, with only 70 cases reported worldwide. We present a case of an 8-year-old girl who presented with a very early onset hemolytic anemia following a mitral valve repair with ring annuloplasty, which necessitated a reoperation. The report also discusses the various mechanisms of traumatic hemolysis associated with valve repair and probable lessons learnt and ways to avoid this complication.

Introduction: Non-invasive tests are used to diagnose and prognosticate Coronary Artery Disease (CAD) patients and also in pre-operative evaluation and rehabilitation. Millions of these tests are performed worldwide in these situations. However, previous studies have shown inappropriate use of these tests. Aim: The study was to evaluate the appropriate use of treadmill exercise test. Materials and Methods: The present retrospective study was done in Rajiv Gandhi Super Speciality Hospital, Raichur and Institute of Medical sciences and RKB Super Speciality Clinic, Raichur, Karnataka, India. Tread Mill Tests (TMT) which were done between November 2013 and February 2016 were included in the study. A total of 600 tests were evaluated for appropriateness. Demographic, clinical and risk factors, indications were studied. Results: Overall 298 (49.66%) tests were found to be inappropriate. Younger age, female sex, pre-operative evaluation, evaluation in master health check up and insurance were predictors of inappropriate use (p

Introduction: Vitamin D deficiency has been found to contribute to various cardiac conditions, such as hypertension, coronary artery disease, stroke, and atherosclerosis. However, the clinical cardiovascular benefits after short term supplementation have not been reported. Aim: To study the beneficial effect of Vitamin D supplementation on angina episodes in Vitamin D deficient patients with chronic stable angina on medical management. Materials and Methods: A total of 40 patients were studied with group 1 (20 patients) with low Vitamin D levels and group 2 with normal Vitamin D levels. 60000 IU of Vitamin D supplementation was given every week for 8 weeks in group 1. Frequency of anginal episodes and use of sub-lingual nitrates were compared at base-line and after 8 weeks post supplementation. Results: Significant 20% (p

Non-protein coding RNA (npcRNA) is a functional RNA molecule that is not translated into a protein. Bacterial npcRNAs are structurally diversified molecules, typically 50-200 nucleotides in length. They play a crucial physiological role in cellular networking, including stress responses, replication and bacterial virulence. In this study, by using an identified npcRNA gene (Sau-02) in Methicillin-resistant Staphylococcus aureus (MRSA), we identified the Gram-positive bacteria S. aureus. A Sau-02-mediated monoplex Polymerase Chain Reaction (PCR) assay was designed that displayed high sensitivity and specificity. Fourteen different bacteria and 18 S. aureus strains were tested, and the results showed that the Sau-02 gene is specific to S. aureus. The detection limit was tested against genomic DNA from MRSA and was found to be ~10 genome copies. Further, the detection was extended to whole-cell MRSA detection, and we reached the detection limit with two bacteria. The monoplex PCR assay demonstrated in this study is a novel detection method that can replicate other npcRNA-mediated detection assays.

Influenza viruses are among the major infectious disease threats of animal and human health. This review examines the recent discovery of novel influenza viruses in bats and cattle, the evolving complexity of influenza virus host range including the ability to cross species barriers and geographic boundaries, and implications to animal and human health.

Objective: This study was to evaluate echocardiographic findings and its usefulness in clinical management of patients with scorpion sting envenomation. Material and Methods: A total of 84 consecutive patients were prospectively studied. The data included demographics, at the time of presentation to the hospital, the clinical features, echocardiographic findings, admission to intensive care unit, use of inotropic medication, time to discharge, and mortality. Results: Out of 84 patients studied 60 patients (71.4%) had echocardiographic evidence of myocarditis (LVEF

Signal transducer and activators of transcription-3 (STAT3) regulates diverse biological functions including cell growth, differentiation, and apoptosis. In addition, STAT3 plays a key role in regulating host immune and inflammatory responses and in the pathogenesis of many cancers. Several studies reported differential regulation of STAT3 in a range of viral infections. Interestingly, STAT3 appears to direct seemingly contradictory responses and both pro- and antiviral roles of STAT3 have been described. This review summarized the currently known functions of STAT3 in the regulation of viral replication and pathogenesis of viral infections. Some of the key unanswered questions and the gap in our current understanding of the role of STAT3 in viral pathogenesis are discussed.

The efflux transporter P-glycoprotein (P-gp) is an important mediator of various pharmacokinetic parameters, being expressed at numerous physiological barriers and also in multidrug-resistant cancer cells. Molecular cloning of homologous cDNAs is an important tool for the characterization of functional differences in P-gp between species. However, plasmids containing mouse mdr1a cDNA display significant genetic instability during cloning in bacteria, indicating that mdr1a cDNA may be somehow toxic to bacteria, allowing only clones containing mutations that abrogate this toxicity to survive transformation. We demonstrate here the presence of a cryptic promoter in mouse mdr1a cDNA that causes mouse P-gp expression in bacteria. This expression may account for the observed toxicity of mdr1a DNA to bacteria. Sigma 70 binding site analysis and GFP reporter plasmids were used to identify sequences in the first 321 bps of mdr1a cDNA capable of initiating bacterial protein expression. An mdr1a M107L cDNA containing a single residue mutation at the proposed translational start site was shown to allow sub-cloning of mdr1a in E. coli while retaining transport properties similar to wild-type P-gp. This mutant mdr1a cDNA may prove useful for efficient cloning of mdr1a in E. coli.

Salmonellosis, a communicable disease caused by members of the Salmonella species, transmitted to humans through contaminated food or water. It is of paramount importance, to generate accurate detection methods for discriminating the various Salmonella species that cause severe infection in humans, including S. Typhi and S. Paratyphi A. Here, we formulated a strategy of detection and differentiation of salmonellosis by a multiplex polymerase chain reaction assay using S. Typhi non-protein coding RNA (sRNA) genes. With the designed sequences that specifically detect sRNA genes from S. Typhi and S. Paratyphi A, a detection limit of up to 10 pg was achieved. Moreover, in a stool-seeding experiment with S. Typhi and S. Paratyphi A, we have attained a respective detection limit of 15 and 1.5 CFU/mL. The designed strategy using sRNA genes shown here is comparatively sensitive and specific, suitable for clinical diagnosis and disease surveillance, and sRNAs represent an excellent molecular target for infectious disease.

Objective: The primary objective of this study was to assess the use of moxonidine, a centrally acting anti–hypertensive agent in real world practice. Material and Methods: Patients who attended out-patients clinic with diagnosis of hypertension were enrolled in the study. Demographics with co-morbid illnesses of all patients were recorded. Patient’s prescriptions were recorded and antihypertensive medications were also analysed. Results: A total of 990 patients were eligible during the study period. Moxonidine was used in 4.54% of patients. Two groups could be identified in moxonidine users – one Group with resistant hypertension (30 patients, 3.03% of total, 66.66% of moxonidine users) on multiple drugs to control BP and another Group with intolerance to conventional, first line drugs (15 patients 1.51% of total, 33.33% of moxonidine users). Moxonidine was not used in newly diagnosed hypertension cases. Resistant hypertension and renal failure predicted the use of moxonidine. Majority of drug used was as per current guidelines. Conclusions: Our study results reflected real world practice of current anti-hypertensive therapy. Patients generally receive medications in accordance with current recommendations and guidelines. Small but significant proportion of patients may require use of drugs like moxonidine to control high BP. Guidelines need to incorporate these real world practices.

The present investigation reports the synthesis of a phenylalanine-rich N-methylated cyclopeptide, cordyheptapeptide A (8), previously isolated from the insect pathogenic fungus Cordyceps sp. BCC 1788, accomplished through the coupling of N-methylated tetrapeptide and tripeptide fragments followed by cyclization of the linear heptapeptide unit. Structure elucidation of the newly synthesized cyclopolypeptide was performed by means of FT-IR, 1H-NMR, 13C-NMR, and fast atom bombardment mass spectrometry (FABMS), and screened for its antibacterial, antidermatophytic, and cytotoxic potential. According to the antimicrobial activity results, the newly synthesized N-Methylated cyclopeptide exhibited potent antibacterial activity against Gram-negative bacteria Pseudomonas aeruginosa and Klebsiella pneumoniae and antifungal activity against dermatophytes Trichophyton mentagrophytes and Microsporum audouinii at a concentration of 6 μg/mL, in comparison to the reference drugs, gatifloxacin and griseofulvin. In addition, cyclopolypeptide 8 displayed suitable levels of cytotoxicity against Dalton’s lymphoma ascites (DLA) and Ehrlich’s ascites carcinoma (EAC) cell lines.

Respiratory epithelial cells play a key role in influenza A virus (IAV) pathogenesis and host innate response. Transformed human respiratory cell lines are widely used in the study of IAV-host interactions due to their relative convenience, and inherent difficulties in working with primary cells. Transformed cells, however, may have altered susceptibility to virus infection. Proper characterization of different respiratory cell types in their responses to IAV infection is therefore needed to ensure that the cell line chosen will provide results that are of relevance in vivo. We compared replication kinetics of human H1N1 (A/USSR/77) IAVs in normal primary human bronchial epithelial (NHBE) and two commonly used respiratory epithelial cell lines namely BEAS-2B and A549 cells. We found that IAV replication was distinctly poor in BEAS-2B cells in comparison with NHBE, A549 and Madin-Darby canine kidney (MDCK) cells. IAV resistance in BEAS-2B cells was accompanied by an activated antiviral state with high basal expression of interferon (IFN) regulatory factor-7 (IRF-7), stimulator of IFN genes (STING) and IFN stimulated genes (ISGs). Treatment of BEAS-2B cells with a pan-Janus-activated-kinase (JAK) inhibitor decreased IRF-7 and ISG expression and resulted in increased IAV replication. Therefore, the use of highly resistant BEAS-2B cells in IAV infection may not reflect the cytopathogenicity of IAV in human epithelial cells in vivo.

A natural heptacyclopeptide, stylissamide G (7), previously isolated from the Bahamian marine sponge Stylissa caribica from the Caribbean Sea, was synthesized via coupling of the tetrapeptide l-phenylalanyl-l-prolyl-l-phenylalanyl-l-proline methyl ester with the tripeptide Boc-l-leucyl-l-isoleucyl-l-proline, followed by cyclization of the linear heptapeptide fragment. The structure of the synthesized cyclooligopeptide was confirmed using quantitative elemental analysis, FT-IR, 1H NMR, 13C NMR and mass spectrometry. Results of pharmacological activity studies indicated that the newly synthesized cycloheptapeptide displayed good anthelmintic potential against Megascoplex konkanensis, Pontoscotex corethruses and Eudrilus eugeniea at 2 mg/mL and in addition, potent antifungal activity against pathogenic Candida albicans and dermatophytes Trichophyton mentagrophytes and Microsporum audouinii at a concentration of 6 μg/mL.

P-glycoprotein (Pgp, ABCB1) is an ATP-Binding Cassette (ABC) transporter that is associated with the development of multidrug resistance in cancer cells. Pgp transports a variety of chemically dissimilar amphipathic compounds using the energy from ATP hydrolysis. In the present study, to elucidate the binding sites on Pgp for substrates and modulators, we employed site-directed mutagenesis, cell- and membrane-based assays, molecular modeling and docking. We generated single, double and triple mutants with substitutions of the Y307, F343, Q725, F728, F978 and V982 residues at the proposed drug-binding site with cys in a cysless Pgp, and expressed them in insect and mammalian cells using a baculovirus expression system. All the mutant proteins were expressed at the cell surface to the same extent as the cysless wild-type Pgp. With substitution of three residues of the pocket (Y307, Q725 and V982) with cysteine in a cysless Pgp, QZ59S-SSS, cyclosporine A, tariquidar, valinomycin and FSBA lose the ability to inhibit the labeling of Pgp with a transport substrate, [(125)I]-Iodoarylazidoprazosin, indicating these drugs cannot bind at their primary binding sites. However, the drugs can modulate the ATP hydrolysis of the mutant Pgps, demonstrating that they bind at secondary sites. In addition, the transport of six fluorescent substrates in HeLa cells expressing triple mutant (Y307C/Q725C/V982C) Pgp is also not significantly altered, showing that substrates bound at secondary sites are still transported. The homology modeling of human Pgp and substrate and modulator docking studies support the biochemical and transport data. In aggregate, our results demonstrate that a large flexible pocket in the Pgp transmembrane domains is able to bind chemically diverse compounds. When residues of the primary drug-binding site are mutated, substrates and modulators bind to secondary sites on the transporter and more than one transport-active binding site is available for each substrate.

The oral second-generation bis-aryl urea fms-like tyrosine kinase 3 (FLT3) inhibitor quizartinib (AC220) has favorable kinase selectivity and pharmacokinetics. It inhibits mutant and wild-type FLT3 in vivo at 0.1 and 0.5 µM, respectively, and has shown favorable activity and tolerability in phase I and II trials in acute myeloid leukemia, with QT prolongation as the dose-limiting toxicity. Co-administration with chemotherapy is planned. We characterized interactions of quizartinib with the ATP-binding cassette (ABC) proteins ABCB1 (P-glycoprotein) and ABCG2 (breast cancer resistance protein). Its effects on uptake of fluorescent substrates and apoptosis were measured by flow cytometry, binding to ABCB1 and ABCG2 drug-binding sites by effects on [¹²⁵I]iodoarylazidoprazosin ([¹²⁵I]-IAAP) photolabeling and ATPase activity, and cell viability by the WST-1 colorimetric assay. Quizartinib inhibited transport of fluorescent ABCG2 and ABCB1 substrates in ABCG2- and ABCB1-overexpressing cells in a concentration-dependent manner, from 0.1 to 5 µM and from 0.5 to 10 µM, respectively, and inhibited [¹²⁵I]-IAAP photolabeling of ABCG2 and ABCB1 with IC₅₀ values of 0.07 and 3.3 µM, respectively. Quizartinib at higher concentrations decreased ABCG2, but not ABCB1, ATPase activity. Co-incubation with quizartinib at 0.1 to 1 µM sensitized ABCG2-overexpressing K562/ABCG2 and 8226/MR20 cells to ABCG2 substrate chemotherapy drugs in a concentration-dependent manner in cell viability and apoptosis assays. Additionally, quizartinib increased cellular uptake of the ABCG2 substrate fluoroquinolone antibiotic ciprofloxacin, which also prolongs the QT interval, in a concentration-dependent manner, predicting altered ciprofloxacin pharmacokinetics and pharmacodynamics when co-administered with quizartinib. Thus quizartinib inhibits ABCG2 at pharmacologically relevant concentrations, with implications for both chemosensitization and adverse drug interactions. These interactions should be considered in the design of treatment regimens combining quizartinib and chemotherapy drugs and in choice of concomitant medications to be administered with quizartinib.