A Novel Para-Amino Salicylic Acid Magnesium Layered Hydroxide Nanocomposite Anti-Tuberculosis Drug Delivery System with Enhanced in vitro Therapeutic and Anti-Inflammatory Properties.

Designing and synthesizing biodegradable drug delivery systems are key research areas in biomedical nanotechnology. Here, we report the development of biodegradable magnesium-layered hydroxide (MgLH) based nanodelivery systems using magnesium oxide (MgO) as the precursor by a precipitation method. The designed nanocarrier does not contain any trivalent metal ions, which are most commonly used for the synthesis of layered double hydroxides (LDHs). The designed delivery system was characterized in detail using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Thermogravimetric analysis (TGA), Transmission electron microscopy (TEM) and inductively coupled plasma (ICP) analyses. The anti-tuberculosis (anti-TB) drug pyrazinamide (PZA) was successfully intercalated into interlayer galleries of MgLH, resulting in the formation of the nanocomposite, PZA-MgLH, having an average size of about 107 ± 24 nm with a uniform circular shape. The in vitro release of PZA in a human body simulated phosphate buffer saline (PBS) solution was sustained (i.e., almost 66 h) and followed a pseudo-secondorder kinetic model. Moreover, the designed nanodelivery system was found to be highly biocompatible with human normal lung cells (MRC-5) and with 3T3 fibroblast cells as controls for 24 and 48 h. Lastly, the PZA-MgLH nanocomposite showed good anti-tuberculosis activity against Mycobacterium tuberculosis and both the PZA-MgLH nanocomposite and its released free drug PZA showed antibacterial activity against tested Gram-positive and Gram-negative bacteria with percentage inhibition ranging from 5.6% to 68% against S. aureus, E. coli, and P. aeruginosa for the PZA free drug, and 32% to 32.5% against E. coli for the PZA-MgLH nanocomposite. In summary, the present results provide significant evidence that the designed nanodelivery system can be used for the delivery of PZA and, thus, should be investigated further for a wide range of anti-TB applications.

Nanomaterials and Nanodevices

We report the intercalation and characterization of para-amino salicylic acid (PASA) into zinc/aluminum-layered double hydroxides (ZLDHs) by two methods, direct and indirect, to form nanocomposites: PASA nanocomposite prepared by a direct method (PASA-D) and PASA nanocomposite prepared by an indirect method (PASA-I). Powder X-ray diffraction, Fourier-transform infrared spectroscopy, and thermogravimetric analysis revealed that the PASA drugs were accommodated within the ZLDH interlayers. The anions of the drug were accommodated as an alternate monolayer (along the long-axis orientation) between ZLDH interlayers. Drug loading was estimated to be 22.8% and 16.6% for PASA-D and PASA-I, respectively. The in vitro release properties of the drug were investigated in physiological simulated phosphate-buffered saline solution of pH 7.4 and 4.8. The release followed the pseudo-second-order model for both nanocomposites. Cell viability (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide [MTT] assays) was assessed against normal human lung fibroblast MRC-5 and 3T3 mouse fibroblast cells at 24, 48, and 72 hours. The results showed that the nanocomposite formulations did not possess any cytotoxicity, at least up to 72 hours.

Infantile hemangiomas (IHs) are the most common tumors of infancy. Imiquimod, an immune-response modifier, has been proven effective and safe in the treatment of superficial and mixed hemangiomas, but severe local reactions caused by imiquimod have been reported sporadically. To evaluate the safety of imiquimod 5% cream and the sequelae of severe local inflammatory reactions in the treatment of superficial IHs we performed a retrospective chart review of all children with superficial IHs who received topical imiquimod treatment in the Department of Plastic and Reconstructive Surgery of Shanghai 9th People's Hospital from March 2010 through February 2012 and selected those who had severe local reactions to topical imiquimod for further description. Nine of 224 (4.0%) children with superficial IHs who received imiquimod 5% cream treatment had severe local reactions. All four patients who had follow-up for longer than 1year had permanent disfiguring depigmented scars after intensive inflammatory reactions. Seven of the severe reactions happened on protruding IHs and four involved the skin folds and joints, suggesting that imiquimod 5% cream should probably be avoided in IHs with either this morphology or these sites.

З метою оцінки якості здійснено кількісне визначення і контроль супутніх домішок протитуберкульозного препарату ІІ ряду протіонаміду. Дослідження проводились методом обернено-фазової високоефективної рідинної хроматографії, на спектрофотометричному детекторі, в ізократичному режимі з детектуванням в УФ- області спектра. Кількісне визначення основної речовини зроблено з використанням зовнішнього стандарту. Для встановлення кількості домішок був застосований метод порівняння з розведеним розчином основної речовини. Показано, що за перевіреними параметрами лікарський препарат відповідає вимогам нормативних документів: містить 99,7 % від заявленої кількості протіонаміду і < 0,54 % домішок.

Background: This aim is so widely used and believed to have healing properties that it is called “true aloe.” Aloe vera has been used for centuries to treat laxity and as a cleansing cleanser. Some of the most common health benefits of are as follows: Promotes wound healing, anti-fungal activity, hypoglycemia or antidiabetes effects, anti-inflammatory properties, anticancer properties, immobilomodulatory properties, and gastroprotective properties. Aims and Objectives: The objective of this study was to determine the antioxidant activity of A. vera juice against antituberculosis drugs ethionamide (ETH) and para-aminosalicylic acid (PAS) by quantifying antioxidant enzymes such as glutathione (GSH) and malondialdehyde (MDA) and catalase (CAT) and electrolytes in rats. Materials and Methods: Fresh leaves of A. vera were collected from botanical garden and the sample was identified. The sample was brought to the laboratory of the Department of Zoology at Patkar-Verde College, Goregaon, Mumbai. 50 g of leaves were ground with 50 mL of distilled water in a sterilized pestle and mortar and the yield so determined by comparing the weight of the extract with the weight of pulp. In the experiment, 48 Sprague-Dawley rats of either sex (average weight 150–250 g) were used. Each group was given the drugs ETH, PAS drug, and A. vera juice on a daily basis for 28 days. The serum of the rat was withdrawn and analyzed for antioxidant enzymes and electrolyte levels. Results: We observed a decrease in the level of GSH in rats treated with anti-tuberculosis (TB) drugs ETH and PAS. However, when A. vera juice was coadministered with PAS, either independently or in combination, it resulted in improved levels of GSH. In addition, the rats treated with A. vera juice showed a decrease in the level of MDA. Furthermore, coadministration of A. vera juice in combination with ETH + PAS + A. vera juice led to increased levels of CAT in rats. The concentration of Na+ in rats treated with A. vera juice in combination with ETH and PAS showed a decrease, which could potentially aid in normal metabolism. On the other hand, the elevation of K+ in the rats treated with A. vera juice indicates their adaptation to salinity, as K+ levels act somatically to prevent influx into roots and shoots. This elevation in K+ can be utilized to lower salt levels in rats experiencing stress. Moreover, the rats treated solely with A. vera juice exhibited the lowest level of Ca+, confirming their low salt stress condition. Finally, it was observed that the rats treated with A. vera juice experienced depletion in A. vera concentration. Conclusion: Based on the aforementioned findings, it can be inferred that A. vera is rich in phenolic and flavonoids, which exhibit antioxidant properties. This unequivocally demonstrates that possesses the ability to scavenge free radicals and plays a beneficial role in combating pathological conditions induced by reactive oxygen species. Furthermore, it has been established that reduces electrolyte levels and diminishes salt accumulation in comparison to groups administered with anti-TB medications ETH and PAS.

Mycobacterium tuberculosis in Solid Organ Transplant Recipients

Among the 731 persons with Mycobacterium tuberculosis infection who were tested in Massachusetts in 1972, an incidence of 3.16% (23 cases) of primary resistance to antituberculous drugs was observed. Nine cases (1.23 %) were resistant to isoniazid alone, and six cases (0.82%) were resistant to three drugs (isoniazid, streptomycin, and either para-aminosalicylic acid or ethambutol). Four cases (0.55%) were resistant to streptomycin and para-aminosalicylic acid combined, and one case (0.14%) was resistant to each of the following: streptomycin alone, isoniazid and streptomycin, isoniazid and para-aminosalicylic acid, and isoniazid and ethambutol. Twelve of the 23 primary drug-resistant patients had a history of alcoholism or addiction to narcotics; 10 of the 12 addicts were infected by multiple drug-resistant tubercle bacilli.

Increased expression of CD11b, the beta-integrin marker of microglia, represents microglial activation during neurodegenerative inflammation. However, the molecular mechanism behind increased microglial CD11b expression is poorly understood. The present study was undertaken to explore the role of nitric oxide (NO) in the expression of CD11b in microglial cells. Bacterial lipopolysaccharide (LPS) induced the production of NO and increased the expression of CD11b in mouse BV-2 microglial cells and primary microglia. Either a scavenger of NO (PTIO) or an inhibitor of inducible nitric-oxide synthase (L-NIL) blocked this increase in microglial CD11b expression. Furthermore, co-microinjection of PTIO with LPS was also able to suppress LPS-mediated expression of CD11b and loss of dopaminergic neuronal fibers and neurotransmitters in striatum in vivo. Similarly, other inducers of NO production such as interferon-gamma, interleukin-1beta, human immunodeficiency virus type-1 gp120, and double-stranded RNA (poly(IC)) also increased the expression of CD11b in microglia through NO. The role of NO in the expression of CD11b was corroborated further by the expression of microglial CD11b by GSNO, an NO donor. Because NO transduces many intracellular signals via guanylate cyclase (GC), we investigated the role of GC, cyclic GMP (cGMP), and cGMP-activated protein kinase (PKG) in microglial expression of CD11b. Inhibition of LPS- and GSNO-mediated up-regulation of CD11b either by NS2028 (a specific inhibitor of GC) or by KT5823 and Rp-8-bromo-cGMP (specific inhibitors of PKG), and increase in CD11b expression either by 8-bromo-cGMP or by MY-5445 (a specific inhibitor of cGMP phosphodiesterase) alone suggest that NO increases microglial expression of CD11b via GC-cGMP-PKG. In addition, GSNO induced the activation of cAMP response element-binding protein (CREB) via PKG that was involved in the up-regulation of CD11b. This study illustrates a novel biological role of NO in regulating the expression of CD11b in microglia through GC-cGMP-PKG-CREB pathway that may participate in the pathogenesis of devastating neurodegenerative disorders.

The treatment of tuberculosis by chemotherapy is complicated due to multiple drug prescriptions, long treatment duration, and adverse side effects. We report here for the first time an in vitro therapeutic effect of nanocomposites based on para-aminosalicylic acid with zinc layered hydroxide (PAS-ZLH) and zinc-aluminum layered double hydroxides (PAS-Zn/Al LDH), against mycobacteria, Gram-positive bacteria, and Gram-negative bacteria. The nanocomposites demonstrated good antimycobacterial activity and were found to be effective in killing Gram-positive and Gram-negative bacteria. A biocompatibility study revealed good biocompatibility of the PAS-ZLH nanocomposites against normal human MRC-5 lung cells. The para-aminosalicylic acid loading was quantified with high-performance liquid chromatography analysis. In summary, the present preliminary in vitro studies are highly encouraging for further in vivo studies of PAS-ZLH and PAS-Zn/Al LDH nanocomposites to treat tuberculosis.

Tuberculosis is a lethal epidemic, difficult to control disease, claiming thousands of lives every year. We have developed a nanodelivery formulation based on para-aminosalicylic acid (PAS) and zinc layered hydroxide using zinc nitrate salt as a precursor. The developed formulation has a fourfold higher efficacy of PAS against mycobacterium tuberculosis with a minimum inhibitory concentration (MIC) found to be at 1.40 μg/mL compared to the free drug PAS with a MIC of 5.0 μg/mL. The newly developed formulation was also found active against Gram-positive bacteria, Gram-negative bacteria, and Candida albicans. The formulation was also found to be biocompatible with human normal lung cells MRC-5 and mouse fibroblast cells-3T3. The in vitro release of PAS from the formulation was found to be sustained in a human body simulated phosphate buffer saline (PBS) solution at pH values of 7.4 and 4.8. Most importantly the nanocomposite prepared using zinc nitrate salt was advantageous in terms of yield and free from toxic zinc oxide contamination and had higher biocompatibility compared to one prepared using a zinc oxide precursor. In summary, these promising in vitro results are highly encouraging for the continued investigation of para-aminosalicylic acid and zinc layered hydroxide nanocomposites in vivo and eventual preclinical studies.

The rationale behind the measurement of anti-tuberculous (Anti-TB) drugs in biological fluids, especially in the management of tuberculous meningitis (TBM), has been briefly discussed. A short review on methods available for laboratory use has been presented. Finally a systematic approach using liquid chromatography (LC) is presented for consideration. This approach involves a preliminary organic solvent extraction of pyrazinamide (PZA) and rifampicin (RIF) and its 25-desacetyl metabolite, 25-DRIF, from cerebrospinal fluid (CSF) or plasma samples. The drugs and their internal standards are separated on a RPB precolumn linked to a μBondapak cartridge in a Zmodule by a gradient solvent program which delivers 6% to 48% v/v of acetonitrile in a phosphate buffer (10 mM KH2PO4 pH3.5) in 10 min at 1.5 ml/min. The eluate is detected at 215 nm. This LC system can also resolve 2 other anti-TB drugs (isoniazid and p-aminosalicylic acid). Patients with TBM were treated with various combinations of anti-TB dr...

The treatment of tuberculosis (TB) poses a major challenge as frontline therapeutic agents become increasingly ineffective with the emergence and spread of drug-resistant strains of Mycobacterium tuberculosis (Mtb). To combat this global health problem, new antitubercular agents with novel modes of action are needed. We have screened a close family of 17 organometallic half-sandwich Os(II) complexes [(arene)Os(phenyl-azo/imino-pyridine)(Cl/I)]+Y– containing various arenes (p-cymene, biphenyl, or terphenyl), and NMe2, F, Cl, or Br phenyl or pyridyl substituents, for activity towards Mtb in comparison with normal human lung cells (MRC5). In general, complexes with a monodentate iodido ligand were more potent than chlorido complexes, and the five most potent iodido complexes (MIC 1.25–2.5 µM) have an electron-donating Me2N or OH substituent on the phenyl ring. As expected, the counter anion Y (PF6–, Cl–, I–) had little effect on the activity. The pattern of potency of the complexes towards Mtb is similar to that towards human cells, perhaps because in both cases intracellular thiols are likely to be involved in their activation and their redox mechanism of action. The most active complex against Mtb is the p-cymene Os(II) NMe2-phenyl-azopyridine iodido complex (2), a relatively inert complex that also exhibits potent activity towards cancer cells. The uptake of Os from complex 2 by Mtb is rapid and peaks after 6 h, with temperature-dependence studies suggesting a major role for active transport. Significance to Metallomics Antimicrobial resistance is a global health problem. New advances are urgently needed in the discovery of new antibiotics with novel mechanisms of action. Half-sandwich organometallic complexes offer a versatile platform for drug design. We show that with an appropriate choice of the arene, an N,N-chelated ligand, and monodentate ligand, half-sandwich organo–osmium(II) complexes can exhibit potent activity towards Mycobacterium tuberculosis (Mtb), the leading cause of death from a single infectious agent. The patterns of activity of the 17 azo- and imino-pyridine complexes studied here towards Mtb and normal lung cells suggest a common redox mechanism of action involving intracellular thiols.

A novel, sensitive, and selective method has been developed for determination of p-aminobenzoic (PABA) and p-aminosalicylic (PAS) acids in the N-benzoyl-L-tyrosyl-PABA/ PAS test. PAS is measured as a ternary complex with terbium and EDTA (lambda(ex) = 324 nm, lambda(em) = 546 nm) in alkaline aqueous solution (pH approximately 12.6), whereas both compounds (PABA and PAS) are measured as ternary complexes with terbium and tri-n-octylphosphine oxide (lambda(ex) = 292 nm, lambda(em) = 546 nm) in weakly acidic aqueous solution (pH approximately 5.5). We inve stigated and implemented optimum conditions for formation of these complexes, yielding respective detection limits for PABA and PAS of 0.07 and 0.02 micromol/L and ranges of application of 0-10 and 0-40 micromol/L (final concentration). The method has been successfully applied to determinations of PABA and PAS in urine and, after alkaline hydrolysis, to determinations of PABA in serum that has been deproteinized with acetonitrile. Within-run imprecision of the PABA determination ranges from 0.8% to 4.2 % for urine samples and from 3.9% to 8.2% for serum samples; day-to-day imprecision varies from 3.2% to 10% for serum samples.

Contribution of Transmembrane Tumor Necrosis Factor to Host Defense against Mycobacterium bovis Bacillus Calmette-Guerin and Mycobacterium tuberculosis Infections