Novel starting points for fragment-based drug design against mycobacterial thioredoxin reductase identified using crystallographic fragment screening.

The increasing number of people dying from tuberculosis and the existence of extensively drug-resistant strains has led to an urgent need for new antituberculotic drugs with alternative modes of action. As part of the thioredoxin system, thioredoxin reductase (TrxR) is essential for the survival of Mycobacterium tuberculosis (Mtb) and shows substantial differences from human TrxR, making it a promising and most likely selective target. As a model organism for Mtb, crystals of Mycobacterium smegmatis TrxR that diffracted to high resolution were used in crystallographic fragment screening to discover binding fragments and new binding sites. The application of the 96 structurally diverse fragments from the F2X-Entry Screen revealed 56 new starting points for fragment-based drug design of new TrxR inhibitors. Over 200 crystal structures were analyzed using FragMAXapp, which includes processing and refinement by largely automated software pipelines and hit identification via the multi-data-set analysis approach PanDDA. The fragments are bound to 11 binding sites, of which four are positioned at binding pockets or important interaction sites and therefore show high potential for possible inhibition of TrxR.

A ready-to-use dry powder formulation based on protamine nanocarriers for pulmonary drug delivery.

The use of oral antibiotic therapy for the treatment of respiratory diseases as tuberculosis has promoted the appearance of side effects as well as resistance to these treatments. The low solubility, high metabolism, and degradation of drugs as rifabutin, have led to the use of combined and prolonged therapies, which difficult patient compliance. In this work, we develop inhalable formulations from biomaterials such as protamine to improve the therapeutic effect. Rifabutin-loaded protamine nanocapsules (NCs) were prepared by solvent displacement method and were physico-chemically characterized and evaluated for their dissolution, permeability, stability, cytotoxicity, hemocompatibility, internalization, and aerodynamic characteristics after a spray-drying procedure. Protamine NCs presented a size of around 200 nm, positive surface charge, and drug association up to 54%. They were stable as suspension under storage, as well as in biological media and as a dry powder after lyophilization in the presence of mannitol. Nanocapsules showed a good safety profile and cellular uptake with no tolerogenic effect on macrophages and showed good compatibility with red blood cells. Moreover, the aerodynamic evaluation showed a fine particle fraction deposition up to 30% and a mass median aerodynamic diameter of about 5 µm, suitable for the pulmonary delivery of therapeutics.

Mycobacterium tuberculosis and Pulmonary Rehabilitation: From Novel Pharmacotherapeutic Approaches to Management of Post-Tuberculosis Sequelae.

Tuberculosis (TB) is still a worldwide public health burden, as more than 1.3 million deaths are expected to be reported in 2021. Even though almost 20 million patients have completed specific anti-TB treatment and survived in 2020, little information is known regarding their pulmonary sequelae, quality of life, and their need to follow rehabilitation services as researchers shifted towards proper diagnosis and treatment rather than analyzing post-disease development. Understanding the underlying immunologic and pathogenic mechanisms during mycobacterial infection, which have been incompletely elucidated until now, and the development of novel anti-TB agents could lead to the proper application of rehabilitation care, as TB sequelae result from interaction between the host and Mycobacterium tuberculosis. This review addresses the importance of host immune responses in TB and novel potential anti-TB drugs' mechanisms, as well as the assessment of risk factors for post-TB disease and usefulness of guidance and optimization of pulmonary rehabilitation. The use of rehabilitation programs for patients who successfully completed anti-tuberculotic treatment represents a potent multifaceted measure in preventing the increase of mortality rates, as researchers conclude that a patient with a TB diagnosis, even when properly completing pharmacotherapy, is threatened by a potential life loss of 4 years, in comparison to healthy individuals. Dissemination of pulmonary rehabilitation services and constant actualization of protocols could strengthen management of post-TB disease among under-resourced individuals.

Synthesis, characterization, and in vitro evaluation of gamma radiationinduced PEGylated isoniazid

Background: The search for innovative anti-tubercular agents has received increasing attention in tuberculosis chemotherapy because Mycobacterium tuberculosis infection has steadily increased over the years. This underlines the necessity for new methods of preparation for polymer-drug adducts to treat this important infectious disease. The use of poly(ethylene glycol)(PEG) is an alternative producing anti-tubercular derivatives. However, it is not yet known whether PEGylated isonicotinylhydrazide conjugates obtained by direct links with PEG are useful for therapeutic applications. Results: Here, we synthesized a PEGylated isoniazid (PEG-g-INH or PEG­INH) by gamma radiation-induced polymerization, for the first time. The new prodrugs were characterized using Raman and UV/Vis spectrometry. The mechanism of PEGylated INH synthesis was proposed. The in vitro evaluation of a PEGylated isonicotinylhydrazide macromolecular prodrug was also carried out. The results indicated that PEG­INH inhibited the bacterial growth above 95% as compared with INH, which showed a lower value (80%) at a concentration of 0.25 µM. Similar trends are observed for 0.1, 1, and 5 µM. Conclusions: In summary, the research suggests that it is possible to covalently attach the PEG onto INH by the proposed method and to obtain a slow-acting isoniazid derivative with little toxicity in vitro and higher antimycobacterial potency than the neat drug.

Possible Biological and Clinical Applications of Phenothiazines.

Phenothiazines have been used in many areas of medicine, mainly in psychopharmacology. These compounds are able to effectively inhibit dopamine, histamine, serotonin, acetylcholine, and α-adrenergic receptors; thus, their effect and side-effect profiles are extremely diverse. Besides their antipsychotic activity, phenothiazines have a significant antimicrobial effect as well, since they can enhance the bactericidal function of macrophages and inhibit efflux pumps. They are also able to eliminate bacterial resistance plasmids and destroy bacteria by their membrane-destabilizing effect. Their antiviral, antiprotozoal, antifungal, and antiprion activities have also been described. Phenothiazines have also been proven to destroy cancer cells and sensitize them to chemotherapy. Anti-angiogenesis and anticancer stem cell activities have also been reported, and they might be applied as adjuvants in the treatment of infections and tumors in the future. Finally, phenothiazines can also be effective in the treatment of neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease.

Discovery of novel N-phenyl 1,4-dihydropyridines with a dual mode of antimycobacterial activity.

There is an urgent need for novel drugs for the treatment of tuberculosis (TB) due to the increasing prevalence of antibiotic resistance among Mycobacterium tuberculosis (Mtb) strains against first-line and second-line therapeutics. We developed novel N-phenyl 1,4-dihydropyridines as potential antituberculotic agents. The observed activity depends on the substitution patterns of the aromatic residues. N-unsubstituted 1,4-dihydropyridines are known inhibitors of the cancer-relevant transmembrane efflux pump ABCB1. Based on the similarity of ABCB1 amino acids sequences relevant to 1,4-dihydropyridine binding and the MTb efflux pump Rv0194, we determined ABCB1-inhibitory properties of our compounds in a cell line model. We identified one compound, which substantially increased the activity of two antituberculotic drugs which are substrates of ABCB1. The data indicate that our N-phenyl 1,4-dihydropyridines represent a novel compound class which improves the efficacy of anti-TB drugs by interfering with transmembrane efflux pumps in Mtb.

Review of the present situation and improvement of the level of reimbursement related to infec-tious diseases medical care:Take tuberculosis as an example / 中国卫生政策研究

Purpose:Taking tuberculosis as an example, this paper aims at to analyzing the level of reimburse-ment for infectious diseases care, and clarifying the government responsibility. Methods:In order to achieve the ob-jective of this research, UHC framework was used to analyze the security level. Result:The findings of this research reveal that TB in-patients' Compensation Ratio of the New Cooperative Medical Scheme ( NCMS) was lower than aver-age level of all the NCMS patients, the out-patients' was even lower. The categories of anti-tuberculotic for free was limited, the utilization was not as expected. Medical assistance covered few people in spite of its high level of reim-bursement. Conclusion:Based on the findings of this review, it has been revealed that the medical insurance didn't make a big difference in financial protection for patients with infectious diseases. As the treatment for of infectious diseases is a quasi-public good, the government has to shoulder the responsibility of improving the compensation ratio of the patients.

Bioavailability of TBI-166, a novel antituberculotic, in beagle dogs / 国际药学研究杂志

Objective To develop a LC-MS/MS method for the quantification of TBI-166, a novel antituberculotic, in beagle dog plasma, and apply it to the pharmacokinetic and bioavailability study. Methods The preparation of plasma sample was a simple deproteinization by the addition of acetonitrile followed by centrifugation. The separation was performed on a Symmetry C 8 column (2.1 mm × 50 mm,3.5μm) with mobile phase of acetonitrile/water containing 0.1%formic acid(V/V) using a gradient elution mode at a flow rate of 0.2 ml/min. The detection was performed in positive selected reaction monitoring (SRM) mode with an electrospray ionization source. The analytes were quantified at m/z 590→478 for TBI-166 and m/z 260→183 for propranolol (internal standard, IS). Results Linear detection responses were obtained for TBI-166 in dog plasma ranging from 2 to 1000 ng/ml. The intra- and inter-day precisions (RSD%) were no more than 10%. The average recovery was greater than 98.6%, and there was good stability and no obvious matrix effect for the quantification. The method was successfully applied in the pharmacokinetic study of TBI-166 in beagle dogs. The AUC(0-t), Cmax and Tmax of TBI-166 in male and female dogs were(897.2±318.6) and(2615.1±1524.4) h·μg/L,(65.4±2.3) and(122.0±34.6) ng/ml and(1.4±0.5) and(4.4±3.5) h after oral administration at 3 mg/kg. The t1/2z, AUC(0-t), and CL of TBI-166 in male and female dogs were (69.6±35.3) and (112.9±25.3) h, (1798.0±729.2) and (3222.4±1656.2) h·μg/L,(0.2±0.1) and (0.3 ±0.1) L/(h·kg) after intravenous administration at 0.5 mg/kg. Conclusion An accurate, simple and sensitive LC-MS/MS method for the determination of TBI-166 in beagle dog plasma was developed and validated. This method was applied to the pharmacokinetic study of TBI-166 in beagle dogs. There was a gender difference on the pharmacokinetic profiles of TBI-166 in dogs. TBI-166 was eliminated slowly and the bioavailability of TBI-166 was 8.3-13.5% in male and female dogs.

Clinical effect and safety of Feilaoling preparation combined with conventional therapy in treatment of pulmonary tuberculosis / 中草药

Objective: To observe the clinical effect and safety of Feilaoling preparation which is a traditional Chinese prescription that can improve immune function in 60 cases of untreated pulmonary tuberculosis patients. Methods: Patients with pulmonary tuberculosis (120 cases) were randomly divided into treatment (n = 60) and control (n = 60) groups. The patients in the treatment group were treated with both Feilaoling preparation and conventional chemotherapy, and the patients in the control group were only treated with conventional chemotherapy. The clinical effects, lesions absorption, and side effects of drugs were observed in two groups. Results: The clinical symptoms and signs in treatment group were better than those in control group. Sputum negative conversion rates of two months and six months and cavitates closure have no significant difference between two groups (P > 0.05). But the hemoptysis treatment, lesions absorption improved, incidence rates of liver damage, and white blood reduction in two groups were all effectively changed, the treatment group was better than the control group (P < 0.05). The treatment group has a significant change compared with the control group (P < 0.01) in the incidence rate of severe gastrointestinal discomfort. Conclusion: Feilaoling preparation has a reliable effect on promotion lesions absorption and reducing the side effects of Western anti-tuberculosis, with certain clinical value.

Activity of Pyrazinamide Gel Against Mycobacterium Tuberculosis in Vitro and Eva luation of Its Security / 中国药房

OBJECTIVE:To observe the activity of Pyrazinamide gel against Mycob ac terium tuberculosis in vitro and its security in bronchial interventional therap y METHODS:The MIC and MBC of Pyrazinamide and Pyrazinamide gel were measured b y handwork method and instrument method and secuity of Pyrazinamide gel was asse ssed by bronchial interventional therapy in rabbits RESULTS:The MICs of pyrazi namide gel to M tuberculosis H37 RV,M bovis and M phlei were 1mg/L,1mg/L,1 0mg/L,the MBCs of Pyrazinamide gel to M tuberculosis H37RV,M bovis and M ph lei were 10mg/L,10mg/L,40mg/L respectively;the MIC and MBC of Pyrazinamide gel and those of Pyrazinamide had no significant differences;the animal security ex periment was negative CONCLUSION:These results suggest that Pyrazinamide gel a nd Pyrazinamide have the same efficacy against M tuberculosis,because carbomer dose not affect the activity of Pyrazinamide against M tuberculosis;Pyrazinami de gel which contains carbomer is safe in bronchial interventional therapy

Efficacy of Reduced Glutathione Against Hepatic Lesion Induced by Antituberculotic Agents / 中国药房

OBJECTIVE:To observe the efficacy of the reduced glutathione against hepatic lesion induced by antituberculotic agents.METHODS:A total of 226 patients with pulmonary tuberculosis undergoing short- course chemotherapy were randomly assigned to receive antituberculotic agents plus reduced glutathione throughout the course(treatment group,n = 114 cases) or to receive Inosine plus Glucurolactone(control group,n = 112).The patients were followed for 3～6 months with the incidence of hepatic lesion compared between the two groups.RESULTS:There were significant differences between the treatment group and the control group in the incidence of hepatic lesion,6 cases(5.3%) in treatment group vs.29 cases (25.9%) in the control group(P

Investigation and Analysis of Antituberculotics Used in 138 Hospitals of Six Cities During the 1999～2001 Period and Trend Analysis / 中国药房

OBJECTIVE:To analyze the present situation and trend of the application of antituberculotics in hospitals of 6 cities METHODS:The antituberculotics used in 138 hospitals of 6 cities during the 1999～2001 period were analysed in respect to the cost,sales volume of pharmaceutical enterprises and situation of clinical application RESULTS:The costs of consumption of antituberculotics were 6 227 520,7 204 738 and 7 537 601 yuan in 1999,2000 and 2001 respectively with a rising trend year by year The average annual cost of antituberculotics was 282 yuan per sickbed CONCLUSION:The antituberculotics are fewer in kind and inexpensive in price but they occupy an important place in a hospital and their consumption is unceasingly increasing

The Present Status of Antituberculotic Drug Markets and Development of the New Varieties of Antituberculotic in China / 中国药房

In the whole world, about 10 millions people suffer from pulmonary tuberculosis each year, of them, three millions died of this disease. At present, there are 5～6 million patients suffering from pulmonary tuberculosis in China. The spread of AIDS results in increase of TB patients. This article emphatically describes the present status of antituberculotie drug markets and the development of the new varieties of antituberculotic in China.

Application of PASS System in Synchronized Monitoring of Medical Orders for Inpatients with Tuberculosis / 中国药房

OBJECTIVE:To evaluate the medical orders in terms of the medication for the inpatients with tuberculosis in our hospital.METHODS:The medical orders for the inpatients in Tuberculosis institute from Dec.7th,2007 to Jan.6th,2008 were synchronously monitored and analyzed.RESULTS:Of the total 5 592 medical orders monitored,1 461 were warned by PASS,of which,562 were warnings about drug interactions,884 about dosage and 15 were about incompatibility.CONCLUSION:Medical orders synchronously monitored by PASS could help correct and monitor the irrational medication.But the function of PASS remained to be strengthened and the data base remained to be enriched and renewed in time.