ABSTRACT
OBJECTIVES: Antioxidant property like radical scavenging is a primary target to elucidate the efficacy mechanism of a drug against diseases linked to oxidative stress such as cancer, metabolic disorders, rheumatoid arthritis, etc. In alternative therapies, homeopathy is one of the preferred choices by patients and clinicians due to its potential to cure chronic and complex illnesses. However, the efficacy of homeopathic preparations at high diluted potencies attracts rational criticism due to insufficient scientific knowledge supporting the mechanism of action. Therefore, an attempt was made to estimate the total phenolic content (TPC) and radical scavenging activity of clinically prescribed homeopathic drugs. METHODS: With gallic acid as a reference control, mother tinctures (MTs) and different potencies of Eucalyptus globulus (EG), Syzygium jambolanum (SJ), Ruta graveolens (RG), and Thuja occidentalis (TO) were used to perform Folin-Ciocalteu test, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. RESULTS: The results showed TPC of MTs equivalent to µg/mL of gallic acid viz; EG (4,872.5 ± 133.2), SJ (8,840.5 ± 14.8), RG (985.6 ± 39.1), and TO (341.5 ± 19.5) with significant ABTS and DPPH radical scavenging potential. Whereas 30C and 200C potencies of each homeopathic drug showed undetectable phenolic content and insignificant radical scavenging potential compared to vehicle control, i.e., alcohol 90% (2.0 ± 1.5). CONCLUSIONS: The reported efficacy of 30C and 200C potencies of homeopathic medicines against oxidative stress-related illnesses might be due to mechanisms other than radical scavenging. Furthermore, the assays studied can be helpful in drug standardization and quality control of MTs that are used as starting material in homeopathic preparations.
Subject(s)
Antioxidants , Homeopathy , Humans , Antioxidants/pharmacology , Antioxidants/chemistry , Homeopathy/methods , Sulfonic Acids/chemistry , Gallic Acid , Phenols/pharmacologyABSTRACT
In the 21st century, the crime rate and viral infectious diseases are on peak and seems to be the real enemies of humanity. Forensic science and its various branches especially biology have a key role in modern-day justice. Forensic scientists and laboratory staffs are of great significance for elucidating the biological exhibits and generating the biological evidence which are required for criminal justice. Owing to the profession and like other medical health workers, forensic laboratory staffs are also at a greater risk in the era of COVID-19. Therefore, the safety of forensic laboratory staff is of utmost importance during this pandemic. The article emphasizes on the safety guidelines and regulations that need to be adopted by the forensic staff in connection with daily laboratory practices. Thus, the article may offer a reference or help one to implement COVID-19 advisory to forensic scientists and other laboratory staff working in forensic institutions and laboratories during the current pandemic.
ABSTRACT
BACKGROUND: Drug susceptibility testing (DST) of Mycobacterium tuberculosis (Mtb) isolates is crucial for the effective treatment of tuberculosis. Data on DST patterns in Mtb isolates in childhood tuberculosis are scanty. AIMS: To determine drug resistance patterns in Mtb isolates from a paediatric TB cohort in North India. METHODS: 403 children aged 6 months to14 year with probable intrathoracic tuberculosis were enrolled prospectively. All were treatment-naïve. 802 ambulatory-induced sputa (IS) and 787 gastric aspirate (GA) samples were cultured in BACTEC-MGIT960 system, and DST of the Mtb isolates was undertaken using the automated BACTEC-MGIT960 SIRE kit. RESULTS: Of the 403 children, 147 (36.4%) were culture-confirmed: 132 (89.8%) isolates were Mtb and 15 (10.2%) non-tuberculous mycobacteria (NTM). Five Mtb isolates were contaminated and the remaining 127 were subjected to in-vitro drug susceptibility testing against streptomycin, isoniazid, rifampicin and ethambutol. Twenty-six (20.47%) isolates were resistant to one or more drugs, seven (5.5%) were resistant to rifampicin singly or in combination, and 11 (8.7%) were resistant to isoniazid singly or in combination. Mono-resistance to isoniazid, rifampicin, streptomycin and ethambutol was detected in four (3.1%), one (0.8%), four (3.1%) and two (1.6%), respectively. Five children (3.9%) had MDR-TB; 101 (79.9%) children had Mtb isolates which were sensitive to all four drugs. CONCLUSIONS: The rifampicin and isoniazid resistance rates were much higher than those in the adult TB population in India.
Subject(s)
Antitubercular Agents/therapeutic use , Drug Resistance, Bacterial , Mycobacterium tuberculosis/isolation & purification , Tuberculosis, Pulmonary/drug therapy , Tuberculosis, Pulmonary/epidemiology , Adolescent , Child , Child, Preschool , Female , Humans , India/epidemiology , Infant , Male , Microbial Sensitivity Tests , Mycobacterium tuberculosis/drug effects , Prevalence , Prospective Studies , Tuberculosis, Pulmonary/microbiologyABSTRACT
BACKGROUND: Tuberculosis (TB) in children is neglected, mainly due to lack of sensitive diagnostic tools. Recently Xpert MTB/RIF assay has revolutionized the diagnostic field, but its usefulness in pediatric TB has not been reported from India and no report is available on its use on long term archived samples. METHODS: We recruited 130 pediatric patients with probable intrathoracic tuberculosis and their gastric aspirate (GA) and induced sputum (IS) samples on 2 consecutive days were collected between January 2009 and December 2012. All samples (n = 520) were subjected to smear examination, BACTEC-MGIT culture and in-house multiplex PCR. An aliquot of each sample was stored at -80 °C and tested in Xpert MTB/RIF assay in 2013. RESULTS: Sample wise and patient wise detection rate of smear microscopy was 4.4 % and 10 %, while for BACTEC-MGIT culture this rate was 24.4 % and 46.9 %, respectively. Of the 130 day 1 GA samples, 31.5 % and 27.7 % day 2 GA samples were culture positive. Only 17.7 % GA samples were positive on both days. Of the 130 IS samples collected on day 1 and day 2, 15.4 % and 23.1 % samples were culture positive. A combination of GA and IS yielded best results. Combining both GA and IS, the overall sensitivity of Xpert MTB/RIF on smear and culture positive samples was 95.6 %. In smear negative and culture positive samples its sensitivity was 62.5 %. The duration of sample storage impacted the Xpert MTB/RIF test performance (p = 0.0001). In smear positive samples stored for 650-849 days, its sensitivity was 85.7 % and 77.1 % for IS and GA samples which dropped to 33.3 % and 50 %, respectively, if stored for more than 1050 days. DISCUSSION: Confirmatory diagnosis of tuberculosis particularly in children is a medical challenge. No laboratory or radiological test can reach to a satisfactory level of diagnostic sensitivity. However, in this study we found that combination of multiple samples and multiple diagnostic tests can give much better yield, though not optimum. In present study, combination of 2 gastric aspirates (GA) and 2 induced sputum (IS) samples collected on two consecutive days, and tested on three diagnostic methods yielded a significantly high detection rate. Despite long term storage, the overall sensitivity of Xpert MTB/RIF on smear and -culture positive samples remained very high. But after storing these samples under subfreezing conditions the sensitivity of Xpert MTB/RIF decreased significantly. This is expected because even if the sample is smear and culture positive, the count of surviving mycobacteria goes down, after several years this count can reach to a undetectable level. CONCLUSION: This report shows that smear and culture positive samples stored at subfreezing conditions for several years can be used in the Xpert MTB/RIF assay, while maintaining appreciable diagnostic test sensitivity and specificity.
Subject(s)
Bacteriological Techniques/methods , Gastric Juice/microbiology , Molecular Diagnostic Techniques/methods , Mycobacterium tuberculosis/isolation & purification , Sputum/microbiology , Tuberculosis, Pulmonary/diagnosis , Adolescent , Child , Child, Preschool , Female , Humans , India , Infant , Male , Microscopy/methods , Randomized Controlled Trials as Topic , Sensitivity and SpecificityABSTRACT
The MTBDRplus line probe assay (LPA) and Xpert MTB/RIF have been endorsed by the World Health Organization for the rapid diagnosis of drug-resistant tuberculosis. However, there is no clarity regarding the superiority of one over the other. In a double-blinded prospective study, we evaluated the efficacy of the Xpert MTB/RIF on samples that were first tested by LPA under the revised national tuberculosis control program of India. A total of 405 sputum samples from suspected drug-resistant tuberculosis patients were included. Of these, 285 smear-positive samples were subjected to LPA. Seventy-two (25.8%) samples showed multidrug resistance, 62 (22.2%) showed rifampin monoresistance, 29 (10.3%) showed isoniazid monoresistance, and 116 (41.5%) were pan-susceptible. Six (2.1%) of the samples gave invalid results. Of the 62 rifampin-monoresistant samples by LPA, 38 (61.4%) showed rifampin resistance, while 21 (33.8%) were found susceptible to rifampin by Xpert MTB/RIF using cartridge version G4. Three (4.8%) samples gave an error. Of the 116 pan-susceptible samples, only 83 were available for Xpert MTB/RIF testing; 4 (5.1%) were rifampin resistant, 74 (94.8%) were susceptible, and 5 (6.0%) showed an error. The 25 discrepant samples were further subjected to MGIT960 drug susceptibility testing. The MGIT960 results showed 100% agreement with LPA results but only 64.4% agreement with Xpert MTB/RIF results. Sequencing analysis of discrepant samples showed 91.3% concordance with LPA but only 8.7% concordance with the Xpert MTB/RIF assay. These findings indicate that by using Xpert MTB/RIF testing we might be underestimating the burden of drug-resistant tuberculosis and indicate that country-specific probes need to be designed to increase the sensitivity of the Xpert MTB/RIF.