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1.
Vet Parasitol ; 283: 109136, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32574977

RESUMO

Bovine babesiosis is continuing as a great threat to the livestock sector causing havoc production losses with significant morbidity and mortality. Being a tick-borne disease, the great complexity in the agent-host- vector relationship has severely hampered the sincere efforts towards the development of an effective vaccine against bovine babesiosis. In these circumstances, assessing the global scenario of disease prevalence is a prerequisite to strategize the available control measures. Keeping this in view, the objective of this study was to estimate the pooled prevalence of bovine babesiosis globally. The literature search was conducted to identify all relevant published articles reporting the prevalence of bovine babesiosis and a total of 163 studies were found eligible for final systematic review and meta-analysis. Meta-analysis was conducted using meta package of R software and summary estimates of the prevalence were calculated. Meta analysis of 81099 samples from 62 countires representing six continents revealed pooled global prevalence of bovine babesiosis as 29% (95% CI = 24%-34%) with estimated prevalence of active infection as 16% (95% CI = 13%-20%) and seroprevalence as 50% (95% CI = 45%-56%) using random effects model. Continent wise highest prevalence of bovine babesiosis in South America 64% (95% CI = 49%-77%) and lowest in Asia 19% (95% CI = 14%-25%). Highest prevalence was estimated with B. bigemina 22% (95% CI = 18%-27%) and least prevalence was recorded with B. divergens 12% (95% CI = 2%-46%). The pooled prevalence estimates generated in the study is revealing an increase in disease trend and the need for immediate planning of mitigation strategies paralleled with the development of early diagnostic methods to reduce the impact of disease throughout the world.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32416594

RESUMO

The metabolic investigation in the drug discovery process is an imperative aspect for selection of drug candidates with excellent therapeutic efficacy and safety profile. Ribociclib (RIBO), an orally active Cyclin dependent kinases inhibitor recently approved by USFDA for its clinical efficacy against human epithelial growth factor receptor negative and hormonal receptor positive advanced breast cancer. Although an in vitro metabolite identification study of RIBO is available in literature, no systematic metabolic investigation including detailed structural characterization and toxicity prediction of the metabolites generated in in vivo system is reported till date. Therefore, in this study, we focused on the characterization of its entire metabolites generated in in vitro as well as in vivo matrices. In vitro study includes incubation of RIBO in rat and human liver microsomes and human S9 fraction, while in vivo study was carried out using plasma, urine and faeces samples of male Sprague Dawley rats. A total of 22 metabolites were successfully separated on Agilent SB C18 (100 × 4.6 mm, 2.7µ) column using ammonium formate (pH 3.5) and acetonitrile as mobile phase. Metabolites were identified with the help of UHPLC-ESI-Q-TOF-MS/MS by accurate mass measurement. RIBO was found to be metabolised by N- dealkylation, sulphation, acetylation, oxidation, hydroxylation, carbonylation, dehydrogenation and by a combination of these reactions. The in silico toxicity profiling of all the metabolites was carried out with the help of ProTox-II software. Ten out of twenty two newly identified metabolites showed to have potential for possessing immunotoxicity. Novelty of this investigation can be justified by the unavailability of any previously published literature on complete in vitro and in vivo metabolite profiling of RIBO. Moreover, in silico toxicity of the metabolites were also not known till date.

3.
Biomed Chromatogr ; 34(6): e4825, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32166756

RESUMO

Treatment through a combination of drugs involving cyclin D-dependent kinase inhibitors like abemaciclib and aromatase inhibitor like letrozole proved to be a potential therapeutic regimen and first-line treatment in estrogen receptor-positive breast cancer. In this study, we developed a simple and simultaneous RP-HPLC bioanalytical method for quantifying abemaciclib and letrozole in rat plasma. Abemaciclib and letrozole were separated on Zorbax Eclipse C18 column employing a gradient elution method comprising 10 mM ammonium acetate (pH 5) and acetonitrile as mobile phase. The method was found to have acceptable selectivity, accuracy (97.20-118.17%), precision (1.10-9.39%) and stability in the validation experiment performed as per the US Food and Drug Administration guidelines. The method sensitivity was low at a concentration level of 100 ng/ml. The applicability of the method has been verified through a single-dose oral pharmacokinetic study in rat. The developed method will be useful to quantitate the analytes in rat plasma samples of different preclinical studies including their pharmacokinetic drug-drug interactions in the future. To date, no method has been reported for the quantification of abemaciclib and letrozole simultaneously in any type of biological matrices. Therefore, this study makes a definite significant contribution in the field of bioanalytical research.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32004940

RESUMO

Flibanserin (FLB) is the first FDA approved drug showed to have significant activity against sexual desire disorder of premenopausal and postmenopausal women. Unfortunately, FLB is used as an adulterant in dietary supplement products as a performance enhancer in sports. Identification of FLB and its metabolites in the biological samples requires an authenticated analytical technique. The aim of this study was to identify N-oxide metabolite of FLB in microsomal and S9 human liver enzyme fractions, rat urine and feces. There are several N-oxide reported as genotoxic impurity or reactive metabolites based on position of N-oxide in piperazine ring. This study also describes the strategy to utilize degradation chemistry for isolation of N-oxide and its step-wise characterization. An LC-MS method has been developed and employed for identifying the N-oxide metabolite of FLB. The targeted N-oxide metabolite in the extracted ion chromatogram of the in vitro and in vivo samples has been confirmed by analyzing the changes in observed mass at m/z 407.1693. Major distinguished abundant ions at m/z 243.1104, 190.0974, 161.0705, 119.0601 confirmed the structure of the metabolite. This study will help to understand the oxidative potential of FLB in toxicokinetic study. The developed method can be useful to identify FLB or its N-oxide metabolite in dope testing in future. This is the first time to report a strategy to utilize degradation chemistry for N-oxide metabolite characterization. In this study, isolated N-oxidative degradation product was used to confirm N-oxide metabolite which was characterized by LC-MS through H/D exchange and structure was ensured by NMR spectroscopy (1H, COSY).


Assuntos
Benzimidazóis , Medição da Troca de Deutério/métodos , Fezes/química , Espectrometria de Massas em Tandem/métodos , Administração Oral , Animais , Benzimidazóis/administração & dosagem , Benzimidazóis/análise , Benzimidazóis/química , Benzimidazóis/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Espectroscopia de Ressonância Magnética , Masculino , Oxirredução , Ratos , Ratos Sprague-Dawley
5.
J Anal Toxicol ; 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32020175

RESUMO

Flibanserin (FLB) is the first USFDA approved serotonin modulator recently marketed to treat acquired generalized women hypoactive sexual desire disorder. The scope of this study was to develop and validate a sensitive, selective and reliable ultra-performance-liquid chromatography-mass spectroscopy/mass spectroscopy based quantification method for FLB in rat plasma as well as brain tissue samples. The method includes a simple liquid-liquid sample extraction procedure. FLB was subjected to chromatographic separation using a poroshell C18 column with the mobile phase comprising a mixture of acetonitrile, 10 mM ammonium acetate and acetic acid (90:10:0.1, v/v/v). Detection and quantification of FLB after positive electrospray ionization was carried out in selective ion monitoring mode. The fragment ion (m/z) of FLB (parent ion: 391.1741) and IS (parent ion: 448.1550) were monitored at 161.0704 and 285.0917, respectively. A linear response of FLB was observed over a concentration range of 2.5 to 600 ng/mL in plasma and 5 to 500 ng/mL in brain tissue homogenate. The intra and inter-day precision and accuracy of the method was met the acceptable limits specified in the USFDA bioanalytical method validation guideline. The analyte was found to be stable in benchtop, freeze-thaw, auto-injector, and dry extract stability studies. The developed method was used to quantitate FLB in the plasma and brain tissue of a single dose oral pharmacokinetic and brain tissue distribution study in female rats. Maximum FLB concentration in plasma and brain were achieved within an hour, however the total amount of the drug that reached the brain was significantly less than in plasma. Rate of elimination of FLB from brain was also faster resulting in a lesser half-life in brain compared to the plasma.

6.
Int J Pharm ; 576: 119018, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31911117

RESUMO

The safety and efficacy of drug substances or products do not solely depend on its active(s). The quantity of impurities present in the product has a significant role in its safety profile. Pharmaceutical impurities are one of the primary reasons for the withdrawal of many approved products from the market. Therefore, the level of impurities in the pharmaceuticals needs to be controlled within a specified safe limit. Nowadays, setting impurity level specification remains a great challenge for pharmaceutical manufacturers. Regulatory guidelines recommend to control the impurity based on the concentration level criteria and provides limits of allowable impurities in pharmaceuticals. However, a single set of impurity limits cannot work for all the drug substances. There are numerous reasons which demand to set the impurity level specification based on safety dominated critical quality attribute principle. In this review, we have discussed the need for the consideration of both concentration based and patient safety-related approaches for setting the impurity level specification. To achieve this goal, it is required to identify the safety limits of the impurities during clinical development and provide a specification for the finished pharmaceutical products before entering the market. However, tremendous challenges faced by pharmaceutical companies to have an appropriate balance amongst the critical factors like safety, efficacy, analytical variability, process knowledge and regulatory requirement. Finally, the specification for API and finished drug product should be established considering both quality and patient safety. Considering all such factors, we have included a systematic and scientific approach that can guide to establish the safe and flexible impurity limit specification for pharmaceuticals.

7.
Int J Neurosci ; : 1-16, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31914343

RESUMO

Reactive oxygen species are generated as a by-product of routine biochemical reactions. However, dysfunction of the antioxidant system or mutations in gene function may result in the elevated production of the pro-oxidant species. Modified endogenous molecules due to chemical interactions with increased levels of reactive oxygen and nitrogen species in the cellular microenvironment can be termed as biomarkers of oxidative stress. 3-Nitrotyrosine is one such promising biomarker of oxidative stress formed due to nitration of protein-bound and free tyrosine residues by reactive peroxynitrite molecules. Nitration of proteins at the subcellular level results in conformational alterations that damage the cytoskeleton and result in neurodegeneration. In this review, we summarized the role of oxidative/nitrosative processes as a contributing factor for progressive neurodegeneration in Alzheimer's disease, Parkinson's disease, Huntington's disease, Lou Gehrig's disease and Prion disease. The selective tyrosine protein nitration of the major marker proteins in related pathologies has been discussed. The alteration in 3-Nitrotyrosine profile occurs well before any symptoms appear and can be considered as a potential target for early diagnosis of neurodegenerative diseases. Furthermore, the reduction in 3-Nitrotyrosine levels in response to treatment with neuroprotective has been highlighted which is indicative of the importance of this particular marker in oxidative stress-related brain and central nervous system pathologies.

8.
Crit Rev Anal Chem ; 50(3): 265-289, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31177807

RESUMO

Dysfunction of the antioxidant system or mutations in the gene may result in the elevated production of certain biomarkers. 3-nitrotyrosine (3-NT) is one such promising biomarker of oxidative stress formed due to nitration of protein bound and free tyrosine residues. It has a significant potential to be exploited for the early diagnosis of diseases. There are a plethora of studies in which 3-NT has been utilized from the pharmacological perspective. However, there is a lack of studies in which the absolute concentration of 3-NT has been reported. Recent breakthrough technologies and modified analytical techniques have been reported to improve the selectivity and sensitivity of 3-NT detection. In this review, we have summarized the modifications to current analytical strategies and advancements in different approaches for 3-NT analysis. For the first time, pre-fabricated biosensors available for 3-NT have been reviewed in this article. A complete discussion on other advanced approaches such as capillary electrophoresis, electron paramagnetic resonance spectroscopy, and electron-vibration-vibration two-dimensional infrared spectroscopy for 3-NT analysis has been made. We have summarized the widest array of conventional and modern analytical techniques reported till date including the recent advancement in the field for the quantification of 3-NT in various types of biological samples.

9.
Crit Rev Anal Chem ; 50(1): 50-61, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30767558

RESUMO

Determination of intracellular concentration becomes essential for the drugs having target receptors or bioactivation site inside the cells. Majority of the antiviral drugs are nucleoside analogs and their intracellular phosphorylated metabolites are active. The anticancer drugs of the cellular enzyme and nucleoside analog category are also required to be undergone intracellular drug level analysis. In this review, we have sequentially described the cell isolation protocols, cell lysis techniques and sample preparation approach to be followed for quantification of intracellular levels of selected antiviral and anticancer drugs. Major limitations for intracellular analyte quantification and their possible way out has been discussed. Currently, no literature is available summarizing these important aspects including bioanalysis of intracellular quantification of either antiviral or anticancer drugs. This review, thus, can be considered to be first of its kind and will be highly useful in providing guidance for intracellular drug analysis aiming determination of the site-specific bioavailability.


Assuntos
Antineoplásicos/análise , Antivirais/análise , Disponibilidade Biológica , Linhagem Celular Tumoral , Separação Celular , Fracionamento Químico , Cromatografia Líquida , Humanos , Manejo de Espécimes/métodos
10.
Neurosci Lett ; 711: 134438, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31422100

RESUMO

Restoration of cellular microenvironment is important in the treatment of neurodegenerative diseases for optimal functioning and survival of neurons. Oxidative stress has been proposed as one of the major pathogenic drivers in Parkinson's disease. Parkinson's model was developed by chronic administration of a pesticide rotenone that inhibits mitochondrial complex I resulting in generation of reactive oxygen species. In this study, our aim was to evaluate neuroprotective effect rendered by edaravone, a potent free radical scavenger in combination with caffeine, an effective inhibitor of adenosine A2A receptor as well as a proven antioxidant. Here we demonstrate that a three-week treatment with edaravone-caffeine combination was able to significantly diminish rotenone induced oxidative damage at the cellular level as well as muscle weakness and cognitive impairment generally associated with Parkinson's disease. This effect is attributable to edaravone's capability of scavenging the perxoynitrite free radical. Herein, we have assessed the levels of protein nitroxidation marker 3-nitrotyrosine in the striatum and lipid peroxidation marker malondialdehyde in striatum, cerebrospinal fluid, plasma and urine of rats. On the 21st day, statistical difference was observed in the striatal biomarker levels (p = 0.001) between the controls, treated and untreated groups. We discovered that when edaravone was co-administered with caffeine, the effect was more significant compared to the group solely treated with edaravone demonstrating a synergistic effect. Simultaneous therapeutic intervention with drug combination showed a pronounced decrease in oxidative damage markers as well as better muscle strength and cognition compared to the untreated groups.

11.
Biomed Chromatogr ; 33(12): e4672, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31386207

RESUMO

The combination of acebrophylline (ABP), levocetirizine (LCZ) and pranlukast (PRN) is used to treat allergic rhinitis, asthma, hay-fever and other conditions where patients experience difficulty in breathing. This study was carried out with the aim of developing and validating a reverse-phase high-performance liquid chromatographic bioanalytical method to simultaneously quantitate ABP, LCZ and PRN in rat plasma. The objective also includes determination of the pharmacokinetic interaction of these three drugs after administration via the oral route after individual and combination treatment in rat. Optimum resolution between the analytes was observed with a C18 Kinetex column (250 mm × 4.6 mm × 5 µm). The chromatography was performed in a gradient elution mode with a 1 mL/min flow rate. The calibration curves were linear over the concentration range of 100-1600 ng/mL. The intra- and inter-day precision and accuracy were found to be within acceptable limits as specified in US Food and Drug Administration guideline for bioanalytical method validation. The analytes were stable on the bench-top (8 h), after three freeze-thaw cycles, in the autosampler (8 h) and as a dry extract (-80°C for 48 h). The statistical results of the pharmacokinetic study in Sprague-Dawley rats showed a significant change in pharmacokinetic parameters for PRN upon co-administration of the three drugs.


Assuntos
Ambroxol/análogos & derivados , Cetirizina , Cromonas , Teofilina/análogos & derivados , Ambroxol/sangue , Ambroxol/química , Ambroxol/farmacocinética , Animais , Cetirizina/sangue , Cetirizina/química , Cetirizina/farmacocinética , Cromatografia Líquida de Alta Pressão , Cromonas/sangue , Cromonas/química , Cromonas/farmacocinética , Limite de Detecção , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Teofilina/sangue , Teofilina/química , Teofilina/farmacocinética
12.
Anal Sci ; 35(10): 1069-1082, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31105088

RESUMO

Sample preparation is a highly important and integral part of bioanalysis for cleaning up the complex biological matrices and thereby minimizing matrix effect. Matrix effect can jeopardize the precise quantification and adversely affect the reliability of liquid chromatography-mass spectrometry-based analytical results by alteration of analyte ionization. Matrix components result in suppression or enhancement of the intensity of analyte response. In spite of the high specificity and selectivity of tandem mass spectrometry, a relatively higher concentration of coeluted matrix elements present in biofluids may alter the efficiency of quantification of a bioanalytical method. Numerous literature reports different types of sample preparation techniques employed in bioanalysis. In this review, the strategies for selection of the appropriate sample clean-up technique in bioanalysis are discussed extensively. A paradigm shift in the arena of sample preparation and bioanalytical approaches involving the liquid chromatography-mass spectroscopic technique has been scrutinized. Current trends and possible future advancements in the field of biological sample extraction methods, including instrumental techniques are analyzed in detail.


Assuntos
Métodos Analíticos de Preparação de Amostras/métodos , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Animais , Precipitação Química , Testes de Química Clínica , Humanos
13.
J Chromatogr Sci ; 57(7): 600-605, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31095671

RESUMO

A simple and sensitive bioanalytical HPLC-UV method has been developed and validated for quantification of eliglustat in rat plasma. The liquid-liquid extraction method was found to be more efficient compared to protein precipitation technique. Chromatographic separation of eliglustat was achieved using Kromasil C18 column with a mobile phase consisting of a mixture of methanol and ammonium acetate (pH 3.2) in a ratio of 60:40. Detection wavelength was set at 282 nm. The developed method was specific, accurate, precise with good recovery and stability profile. The calibration curve constructed over a range of 0.3-10 µg/mL was linear (R2 > 0.997). Accuracy in intra and inter-day assay were found to be 96.27-107.35% and 96.80-106.57%, respectively. The corresponding precision (%CV) values were within 4.31-10.90% and 4.82-9.97%, respectively. Till date, no method is available for bioanalysis of eliglustat in any type of biological matrix. This is the first time to report a bioanalytical method for this molecule. The developed bioanalytical method was applied to quantitate eliglustat in the plasma samples of a single dose oral pharmacokinetic study in Sprague Dawley rat.


Assuntos
Pirrolidinas/sangue , Animais , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Modelos Lineares , Masculino , Pirrolidinas/química , Pirrolidinas/farmacocinética , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
14.
Int J Pharm ; 565: 258-268, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31095983

RESUMO

Intranasal delivery has shown to circumvent blood-brain-barrier (BBB) and deliver the drugs into the CNS at a higher rate and extent than other conventional routes. The mechanism of drug transport from nose-to-brain is not fully understood yet, but several neuronal pathways are considered to be involved. Intranasal nanoemulsion for brain targeting is investigated extensively. Higher brain distribution of drug after administering intranasal nanoemulsion was established by many researchers. Issues with nasomucosal clearance are solved by formulating modified nanoemulsion; for instance, mucoadhesive nanoemulsion or in situ nanoemulgel. However, no intranasal nanoemulsion for brain targeted drug delivery has been able to cross the way from 'benches to bed-side' of patients. Possibilities of toxicity by repeated administration, irregular nasal absorption during the diseased condition, use of a high amount of surfactants are few of the persisting challenges that need to overcome in coming days. Understanding the ways how current developments has solved some challenges is necessary. At the same time, the future direction of the research on intranasal nanoemulsion should be figured out based on existing challenges. This review is focused on the current developments of intranasal nanoemulsion with special emphasis on the existing challenges that would help to set future research direction.


Assuntos
Encéfalo/metabolismo , Sistemas de Liberação de Medicamentos , Nanopartículas/administração & dosagem , Mucosa Nasal/metabolismo , Administração Intranasal , Animais , Emulsões , Humanos
15.
Anal Sci ; 35(7): 719-732, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-30905906

RESUMO

Significant numbers of newer anticancer drugs are regularly entering into the market worldwide to fight against different types of cancers. Analytical methodologies are being developed to quantitate those molecules in a variety of matrices during their drug development stages. Selection of biological matrices for developing bioanalytical methods is based on the mechanism of action, site of action, site of metabolism and route of excretion of the drugs or their metabolites. In this review, we have described the current scenario and advancements in bioanalytical techniques for quantification of different anticancer drugs in a variety of biomatrices with a special emphasis on sample preparation techniques. We have discussed and summarized different bioanalytical aspects for anticancer drugs, which can give direction to the researcher for choosing appropriate techniques for their quantification needs.


Assuntos
Antineoplásicos/análise , Testes de Química Clínica/métodos , Métodos Analíticos de Preparação de Amostras , Antineoplásicos/sangue , Antineoplásicos/urina , Humanos
16.
Bioanalysis ; 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30663327

RESUMO

Analytical techniques may not be compatible or sufficiently sensitive to the analytes, unless it undergoes a specific sample extraction procedure. Sample extraction can be considered as one of the key steps in analysis. Analysis of a poorly treated sample may produce inferior quality of analytical data. Continuous advancement and development of newer sample extraction techniques such as solid phase microextraction, ultrasound, magnetically and microwave assisted magnetic extraction; electro-membrane extraction and dried blood spotting are to address the shortcomings of the existing techniques and to provide more automation, minimizing preparation time and make them high throughput. This review summarizes the suitability of application of the advanced sample preparation techniques available for chemical and bioanalysis in a comprehensive manner. This review also provides a scientific guidance for selecting the appropriate sample extraction technique based on sample type.

17.
Drug Dev Res ; 79(8): 391-399, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30329161

RESUMO

Hit, Lead & Candidate Discovery The thiazole ring system represents a significant building block that exists in many biologically active natural products and clinically successful anticancer drugs. Modifications of the thiazole core have been a proven and highly effective method in improving anticancer potency. We designed a novel thiazole-based molecule, 4-(dimethylamino)-2-(p-tolylamino) thiazole-5-carbonitrile, which showed potent in vitro anticancer effect against targeted Bcl-2 Jurkat cell-line quantified using 3-(4, 5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Physicochemical parameters (pKa, LogP, LogD) of the molecule have also been evaluated as a part of the drug development process. Moreover, a rapid Reverse phase-high performance liquid chromatography (RP-HPLC) bioanalytical method has been developed to quantitate the molecule in human plasma. The method has been validated following the United States Food and Drug Administration bioanalytical method validation guideline. The stability studies showed no significant instability of the analyte in respective stability conditions (6 hr autosampler, 8 hr bench top, 30 days long-term, and 3 freeze-thaw cycles). The molecule was found to be stable for 3 hr in human plasma. The molecule was shown to have high plasma protein binding affinity. It showed favorable pKa (11), Log P (3.01), Log D (2.96), and plasma protein binding (90%) values toward its further exploitation as a lead anticancer candidate molecule. The developed bioanalytical method can be used for quantifying the molecule in different pharmacokinetic, toxicokinetic, or other clinical trial samples involving human plasma during development process or in routine bioavailability and bioequivalence study after its regulatory approval.


Assuntos
Antineoplásicos/análise , Antineoplásicos/sangue , Desenvolvimento de Medicamentos/métodos , Tiazóis/análise , Tiazóis/sangue , Proteínas Sanguíneas/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Células Jurkat , Ligação Proteica/fisiologia , Reprodutibilidade dos Testes
18.
Artigo em Inglês | MEDLINE | ID: mdl-30179754

RESUMO

Ethyl 3-(2-(4-fluorophenyl)amino)-4-phenylthiazo)-5-yl)-3-oxopropanoate is a novel molecule with potent acetylcholinesterase inhibition property. In this research, we have developed a rapid and selective RP-HPLC bioanalytical method for quantitative measurement of the molecule. The method has been validated following the USFDA bioanalytical method validation guideline. In addition, as a part of drug development, in vitro metabolite identification has also been performed. A Kromasil C18 column was used in eluting the molecule chromatographically. The optimized mobile phase was composed of a mixture of acetonitrile and 10 mM ammonium formate buffer (pH 4.6) in 70:30 ratio (v/v). The response of the molecule was found to be linear over a calibration range of 0.2 µg/mL to 12 µg/mL. The inter-day and intra-day accuracy of the method ranged from 89.95% to 101.90% and 99.84% to 104.08%, respectively. On the other hand, the precision (%CV) value for inter-day was in between 3.50% to 6.91% and for intra-day, it was 2.11% to 8.03%. The mean recovery of the molecule at three different quality control levels was more than 85%. The analyte was stable under different stability conditions including 12 h autosampler, 8 h bench top, 15 days long term at -20 °C and three freeze-thaw cycles. The method was applied to determine stability of the molecule in human plasma. The molecule was found to be stable with more than 90% remaining even after 120 min of incubation in plasma. Two metabolites each in rat liver microsome and human liver microsome has been identified.


Assuntos
Inibidores da Colinesterase/análise , Inibidores da Colinesterase/metabolismo , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Inibidores da Colinesterase/sangue , Inibidores da Colinesterase/química , Humanos , Modelos Lineares , Microssomos Hepáticos/metabolismo , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Acta Parasitol ; 63(3): 609-616, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-29975642

RESUMO

Fasciolosis in ruminants in India is caused by the liver fluke Fasciola gigantica. Radix (Lymnaea) spp. are known to carry the infective stages of this parasite. Understanding the seasonal prevalence of F. gigantica infection in the intermediate host is of extreme importance in order to elucidate the transmission dynamics of the parasite. So the present study was designed to determine the bioclimatic distribution of larval stages of F. gigantica in Radix spp. snails as well as to explore the genetic diversity of F. gigantica in three geographical regions (Deccan plateau, Western Ghats and coastal region) of Karnataka. The lymnaeid snails were sampled (n = 2077) for a period of one year (June 2015 to May 2016) at 24 sites. The snails were morphologically identified and the infection status was established through cercarial shedding and nested polymerase chain reaction (PCR) based technique targeting second internal transcribed spacers (ITS-2) of nuclear ribosomal DNA. The sensitivity of PCR (8.2%) for detection of F. gigantica infection within snail is significantly higher than cercarial shedding (4.3%) with an overall prevalence of 5.1%. The prevalence of infection was higher in winter than in the rainy and summer seasons (6.2% instead of 4.6% and 4.3% respectively). Deccan plateau (5.8%) showed a higher prevalence of infection compared to Western Ghats (5.2%) and Coastal region (3.6%). The sequencing ITS-2 region permitted the identification of the parasite as F. gigantica which is having high implication in studying the population genetic structure of the parasite in the country. In conclusion, overall results indicated that Radix spp. snails harboured F. gigantica developmental stages throughout the year and nested PCR was found to be sensitive and specific for detection of F. gigantica infection in snails compared to routine parasitological techniques.


Assuntos
Fasciola hepatica/genética , Fasciolíase/veterinária , Animais , Cercárias , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Fasciola hepatica/isolamento & purificação , Fasciolíase/epidemiologia , Fasciolíase/parasitologia , Índia/epidemiologia , Larva , Filogenia , Reação em Cadeia da Polimerase/veterinária , Ruminantes , Sensibilidade e Especificidade , Caramujos/parasitologia
20.
Int J Pharm ; 543(1-2): 328-344, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29635054

RESUMO

Different regulatory guidelines recommend establishing stability profile of pharmaceuticals at the time of drug development. The expiry date, retesting period and storage conditions of active drugs or products are established through stability analysis. Several regulatory guidelines exist for stability testing of pharmaceuticals. Mostly, ICH stability guidelines are followed in practice. This guideline recommends to validate stability indicating method using forced degradation samples that contains all possible degradation impurities. ICH guidelines provide general recommendations for inclusion of stability indicating parameters in a stability testing protocol. However, those guidelines do not provide specific requirements and experimental methodology to be followed for stability studies. Due to this gap, often confusion arises in the scientific community in designing stability testing protocol. Therefore, significant variations are observed in reported literature in selection of stability indicating parameters. Procedural dissimilarity amongst reported stability studies is also evident. This review discusses the regulatory guidelines and procedures to follow in performing stability testing of pharmaceuticals. Scope of this review also includes recommendations on practical approaches for designing stability testing protocol to fulfill current regulatory requirements for drug substances and their formulations.


Assuntos
Química Farmacêutica/legislação & jurisprudência , Estabilidade de Medicamentos , Legislação de Medicamentos , Química Farmacêutica/métodos
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