Identification of monoclonal antibody drug substances using non-destructive Raman spectroscopy.

Monoclonal antibodies provide highly specific and effective therapies for the treatment of chronic diseases. These protein-based therapeutics, or drug substances, are transported in single used plastic packaging to fill finish sites. According to good manufacturing practice guidelines, each drug substance needs to be identified before manufacturing of the drug product.

Biochemical and molecular properties of LHCX1, the essential regulator of dynamic photoprotection in diatoms.

Light harvesting is regulated by a process triggered by the acidification of the thylakoid lumen, known as nonphotochemical "energy-dependent quenching" (qE). In diatoms, qE is controlled by the light-harvesting complex (LHC) protein LHCX1, while the LHC stress-related (LHCSR) and photosystem II subunit S proteins are essential for green algae and plants, respectively. Here, we report a biochemical and molecular characterization of LHCX1 to investigate its role in qE.

A novel method produces native light-harvesting complex II aggregates from the photosynthetic membrane revealing their role in nonphotochemical quenching.

Nonphotochemical quenching (NPQ) is a mechanism of regulating light harvesting that protects the photosynthetic apparatus from photodamage by dissipating excess absorbed excitation energy as heat. In higher plants, the major light-harvesting antenna complex (LHCII) of photosystem (PS) II is directly involved in NPQ. The aggregation of LHCII is proposed to be involved in quenching.

Rapid regulation of photosynthetic light harvesting in the absence of minor antenna and reaction centre complexes.

Plants are subject to dramatic fluctuations in the intensity of sunlight throughout the day. When the photosynthetic machinery is exposed to high light, photons are absorbed in excess, potentially leading to oxidative damage of its delicate membrane components. A photoprotective molecular process called non-photochemical quenching (NPQ) is the fastest response carried out in the thylakoid membranes to harmlessly dissipate excess light energy.

Novel Tetrahydroquinazolinamines as Selective Histamine 3 Receptor Antagonists for the Treatment of Obesity.

The histamine 3 receptor (H3R) is a presynaptic receptor, which modulates several neurotransmitters including histamine and various essential physiological processes, such as feeding, arousal, cognition, and pain. The H3R is considered as a drug target for the treatment of several central nervous system disorders. We have synthesized and identified a novel series of 4-aryl-6-methyl-5,6,7,8-tetrahydroquinazolinamines that act as selective H3R antagonists.

An insight into tetrahydro-β-carboline-tetrazole hybrids: synthesis and bioevaluation as potent antileishmanial agents.

A series of 2,3,4,9-tetrahydro-β-carboline tetrazole derivatives () have been synthesized utilizing the Ugi multicomponent reaction and were identified as potential antileishmanial chemotypes. Most of the screened derivatives exhibited significant activity against the promastigote (IC from 0.59 ± 0.

Plant and algal chlorophyll synthases function in Synechocystis and interact with the YidC/Alb3 membrane insertase.

In the model cyanobacterium Synechocystis sp. PCC 6803, the terminal enzyme of chlorophyll biosynthesis, chlorophyll synthase (ChlG), forms a complex with high light-inducible proteins, the photosystem II assembly factor Ycf39 and the YidC/Alb3/OxaI membrane insertase, co-ordinating chlorophyll delivery with cotranslational insertion of nascent photosystem polypeptides into the membrane. To gain insight into the ubiquity of this assembly complex in higher photosynthetic organisms, we produced functional foreign chlorophyll synthases in a cyanobacterial host.

Ycf48 involved in the biogenesis of the oxygen-evolving photosystem II complex is a seven-bladed beta-propeller protein.

Robust photosynthesis in chloroplasts and cyanobacteria requires the participation of accessory proteins to facilitate the assembly and maintenance of the photosynthetic apparatus located within the thylakoid membranes. The highly conserved Ycf48 protein acts early in the biogenesis of the oxygen-evolving photosystem II (PSII) complex by binding to newly synthesized precursor D1 subunit and by promoting efficient association with the D2 protein to form a PSII reaction center (PSII RC) assembly intermediate. Ycf48 is also required for efficient replacement of damaged D1 during the repair of PSII.

Molecular Origin of Photoprotection in Cyanobacteria Probed by Watermarked Femtosecond Stimulated Raman Spectroscopy.

Photoprotection is fundamental in photosynthesis to avoid oxidative photodamage upon excess light exposure. Excited chlorophylls (Chl) are quenched by carotenoids, but the precise molecular origin remains controversial. The cyanobacterial HliC protein belongs to the Hlip family ancestral to plant light-harvesting complexes, and binds Chl a and β-carotene in 2:1 ratio.

Liquid chromatography-tandem mass spectrometry method for the quantification of a potent H receptor antagonist conessine in serum and its application to pharmacokinetic studies.

Conessine, a steroidal alkaloid obtained from the bark and seeds of the plant species of Apocynaceae family, elicits a histamine antagonistic action, selectively for the H histaminergic receptors. This alkaloid is used mainly for the treatment of dysentery and helminthic disorders. For the quantification of conessine in serum, a liquid chromatography-tandem mass spectrometry method was developed.

Binding of pigments to the cyanobacterial high-light-inducible protein HliC.

Cyanobacteria possess a family of one-helix high-light-inducible proteins (HLIPs) that are widely viewed as ancestors of the light-harvesting antenna of plants and algae. HLIPs are essential for viability under various stress conditions, although their exact role is not fully understood. The unicellular cyanobacterium Synechocystis sp.

Substituted carbamothioic amine-1-carbothioic thioanhydrides as novel trichomonicidal fungicides: Design, synthesis, and biology.

Sexually transmitted diseases like trichomoniasis along with opportunistic fungal infections like candidiasis are major global health burden in female reproductive health. In this context a novel non-nitroimidazole class of substituted carbamothioic amine-1-carbothioic thioanhydride series was designed, synthesized, evaluated for trichomonacidal and fungicidal activities, and was found to be more active than the standard drug Metronidazole (MTZ). Compounds were trichomonicidal in the MIC ranges of 4.

Model based population PK-PD analysis of furosemide for BP lowering effect: A comparative study in primary and secondary hypertension.

Though numerous reports have demonstrated multiple mechanisms by which furosemide can exert its anti-hypertensive response. However, lack of studies describing PK-PD relationship for furosemide featuring its anti-hypertensive property has limited its usage as a blood pressure (BP) lowering agent. Serum concentrations and mean arterial BP were monitored following 40 and 80mgkg multiple oral dose of furosemide in spontaneously hypertensive rats (SHR) and DOCA-salt induced hypertensive (DOCA-salt) rats.

Effect of arteether and pyrimethamine coadministration on the pharmacokinetic and pharmacodynamic profile of ormeloxifene.

The study was intended to investigate the effect of concomitant administration of antimalarial drug (pyrimethamine or arteether) on pharmacokinetic and post coitus contraceptive efficacy of ormeloxifene in female Sprague-Dawley rats. A serial sampling technique coupled with LC-MS/MS detection was utilized for quantification of ormeloxifene in plasma samples collected from female rats treated with ormeloxifene only and ormeloxifene with pyrimethamine or arteether. Coitus-proven female rats were utilized to investigate the effect of pyrimethamine or arteether coadministration on contraceptive efficacy of ormeloxifene by investigating the presence or absence of implantations and status of corpora lutea on day 10 post coitum.

Novel aryl piperazines for alleviation of 'andropause' associated prostatic disorders and depression.

A series of seventeen piperazine derivatives have been synthesized and biologically evaluated for the management of andropause-associated prostatic disorders and depression. Five compounds 16, 19, 20, 21 and 22 significantly inhibited proliferation of androgen-sensitive LNCaP prostatic cell line with EC values of 12.4 μM, 15.

Simultaneous LC-MS-MS Determination of Lopinavir and Rifabutin in Human Plasma.

Tuberculosis (TB) with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome represents the most common infectious diseases worldwide. Anti-TB drugs are used concurrently with antiretroviral drug for treatment of TB-HIV co-morbidities. Due to lower risk of interaction with protease inhibitors, rifabutin is preferred over rifampicin in treatment of HIV and TB co-morbidity.

Twisting a β-Carotene, an Adaptive Trick from Nature for Dissipating Energy during Photoprotection.

Cyanobacteria possess a family of one-helix high light-inducible proteins (Hlips) that are homologous to light-harvesting antenna of plants and algae. An Hlip protein, high light-inducible protein D (HliD) purified as a small complex with the Ycf39 protein is evaluated using resonance Raman spectroscopy. We show that the HliD binds two different β-carotenes, each present in two non-equivalent binding pockets with different conformations, having their (0,0) absorption maxima at 489 and 522 nm, respectively.

Preclinical pharmacokinetics and ADME characterization of a novel anticancer chalcone, cardamonin.

Cardamonin (CRD), a chalconoid obtained from several medicinal plants of Zingiberaceae family, had shown promising potential in cancer prevention and therapy. For further development and better pharmacological elucidation, we performed a series of in vitro and in vivo studies to characterize its preclinical pharmacokinetics. The study samples were analyzed using validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) and high performance liquid chromatography-ultra violet (HPLC-UV) methods.

A combination of complexation and self-nanoemulsifying drug delivery system for enhancing oral bioavailability and anticancer efficacy of curcumin.

Objective: Curcumin, the golden spice from Indian saffron, has shown chemoprotective action against many types of cancer including breast cancer. However, poor oral bioavailability is the major hurdle in its clinical application. In the recent years, self-nanoemulsifying drug delivery system (SNEDDS) has emerged as a promising tool to improve the oral absorption and enhancing the bioavailability of poorly water-soluble drugs.

2-Methyl-4/5-nitroimidazole derivatives potentiated against sexually transmitted Trichomonas: Design, synthesis, biology and 3D-QSAR study.

Trichomoniasis is the most prevalent, non-viral sexually transmitted diseases (STD) caused by amitochondriate protozoan Trichomonas vaginalis. Increased resistance of T. vaginalis to the marketed drug Metronidazole necessitates the development of newer chemical entities.

PEGylated chitosan nanoparticles potentiate repurposing of ormeloxifene in breast cancer therapy.

Aim: Development and optimization of ormeloxifene-loaded PEGylated chitosan nanoparticles (CNPs) for enhancing its literature profound therapeutic activity against breast cancer.

Methods: CNPs were prepared by ionotropic gelation method and characterized.

Results: Optimized formulation (CNPs10) had average 304 nm particle size with 0.

Insights into the pharmacokinetic properties of antitubercular drugs.

Introduction: The furiously advancing cases of multidrug-resistant tuberculosis (TB) along with the recent emergence of total drug resistant TB and TB-AIDS comorbidity present an increased threat to global public health. Knowledge of pharmacokinetic properties helps in selecting an appropriate anti-TB dosage regimen to achieve optimal results in patients.

Areas Covered: This article provides a brief compilation of the information available regarding published pharmacokinetic data for anti-TB drugs and may act as a single window for investigators/medical practitioners in this field.

Role of enterohepatic recirculation in drug disposition: cooperation and complications.

Enterohepatic recirculation (EHC) concerns many physiological processes and notably affects pharmacokinetic parameters such as plasma half-life and AUC as well as estimates of bioavailability of drugs. Also, EHC plays a detrimental role as the compounds/drugs are allowed to recycle. An in-depth comprehension of this phenomenon and its consequences on the pharmacological effects of affected drugs is important and decisive in the design and development of new candidate drugs.

LC-coupled ESI MS for quantification of miltefosine in human and hamster plasma.

Background: Leishmaniasis, a fatal parasitic disease, is the second largest parasitic killer in the world and miltefosine is the first and only oral drug available for its treatment.

Results: A rapid, sensitive and simple LC-MS/MS method for miltefosine quantification in hamster and human plasma was developed and validated over the range of 2.5-400 ng/ml.

Identification of gallic acid based glycoconjugates as a novel tubulin polymerization inhibitors.

A novel class of gallic acid based glycoconjugates were designed and synthesized as potential anticancer agents. Among all the compounds screened, compound 2a showed potent anticancer activity against breast cancer cells. The latter resulted in tubulin polymerization inhibition and induced G2/M cell cycle arrest, generation of reactive oxygen species, mitochondrial depolarization and subsequent apoptosis in breast cancer cells.