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1.
Vet Parasitol Reg Stud Reports ; 37: 100825, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36623905

RESUMO

In tropical countries like Pakistan, ticks are the most prevalent vectors for transmitting diseases to wild and domestic animals leading to their morbidity and mortality. In the present study, a total of 593 ticks infesting one-humped camels (n = 244) were collected during April till June 2021 from two tehsils of Layyah district located in Punjab (Pakistan) in order to investigate their diversity, prevalence and distribution. Data analysis revealed that camels located in Tehsil Choubara were significantly more tick infested than camels from Tehsil Layyah (P = 0.02). It was observed that the older camels were more prone to tick infestation that younger ones. Hyalomma and Rhipicephalus were the two tick genera identified during the present study and tick specimens of Hyalomma genus were the most prevalent (n = 590, 99.5%). In particular, Hyalomma dromedarii was the most prevalent tick species (n = 559, 94.3%), followed by Hyalomma anatolicum (n = 24, 4%), Hyalomma marginatum (n = 7, 1.2%) and Rhipicephalus sanguineus sensu lato (n = 3, 0.5%). The overall abundance of male ticks was higher than the female ticks with a ratio of 1:2.1. Neck was the most preferred site for the tick infestation followed by ventral, sternum, under tail, head, udder and back of analyzed camels. To our knowledge, this is the first report regarding tick diversity on camels from Layyah district and based on our finding, we recommend large-scale tick control strategies to be implemented in this district to uplift the livestock sector.


Assuntos
Ixodidae , Rhipicephalus , Infestações por Carrapato , Masculino , Feminino , Animais , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/veterinária , Camelus , Prevalência , Paquistão/epidemiologia
2.
Biol Rev Camb Philos Soc ; 97(5): 1823-1843, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35580905

RESUMO

Convergence is the phenomenon whereby similar phenotypes evolve independently in different lineages. One example is resistance to toxins in animals. Toxins have evolved many times throughout the tree of life. They disrupt molecular and physiological pathways in target species, thereby incapacitating prey or deterring a predator. In response, molecular resistance has evolved in many species exposed to toxins to counteract their harmful effects. Here, we review current knowledge on the convergence of toxin resistance using examples from a wide range of toxin families. We explore the evolutionary processes and molecular adaptations driving toxin resistance. However, resistance adaptations may carry a fitness cost if they disrupt the normal physiology of the resistant animal. Therefore, there is a trade-off between maintaining a functional molecular target and reducing toxin susceptibility. There are relatively few solutions that satisfy this trade-off. As a result, we see a small set of molecular adaptations appearing repeatedly in diverse animal lineages, a phenomenon that is consistent with models of deterministic evolution. Convergence may also explain what has been called 'autoresistance'. This is often thought to have evolved for self-protection, but we argue instead that it may be a consequence of poisonous animals feeding on toxic prey. Toxin resistance provides a unique and compelling model system for studying the interplay between trophic interactions, selection pressures and the molecular mechanisms underlying evolutionary novelties.


Assuntos
Adaptação Fisiológica , Evolução Biológica , Adaptação Fisiológica/genética , Animais , Fenótipo
3.
Toxins (Basel) ; 12(10)2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33023159

RESUMO

Venomous snakes are important subjects of study in evolution, ecology, and biomedicine. Many venomous snakes have alpha-neurotoxins (α-neurotoxins) in their venom. These toxins bind the alpha-1 nicotinic acetylcholine receptor (nAChR) at the neuromuscular junction, causing paralysis and asphyxia. Several venomous snakes and their predators have evolved resistance to α-neurotoxins. The resistance is conferred by steric hindrance from N-glycosylated asparagines at amino acids 187 or 189, by an arginine at position 187 that has been hypothesized to either electrostatically repulse positively charged neurotoxins or sterically interfere with α-neurotoxin binding, or proline replacements at positions 194 or 197 of the nAChR ligand-binding domain to inhibit α-neurotoxin binding through structural changes in the receptor. Here, we analyzed this domain in 148 vertebrate species, and assessed its amino acid sequences for resistance-associated mutations. Of these sequences, 89 were sequenced de novo. We find widespread convergent evolution of the N-glycosylation form of resistance in several taxa including venomous snakes and their lizard prey, but not in the snake-eating birds studied. We also document new lineages with the arginine form of inhibition. Using an in vivo assay in four species, we provide further evidence that N-glycosylation mutations reduce the toxicity of cobra venom. The nAChR is of crucial importance for normal neuromuscular function and is highly conserved throughout the vertebrates as a result. Our research shows that the evolution of α-neurotoxins in snakes may well have prompted arms races and mutations to this ancient receptor across a wide range of sympatric vertebrates. These findings underscore the inter-connectedness of the biosphere and the ripple effects that one adaption can have across global ecosystems.


Assuntos
Resistência a Medicamentos , Evolução Molecular , Junção Neuromuscular/efeitos dos fármacos , Neurotoxinas/toxicidade , Antagonistas Nicotínicos/toxicidade , Receptores Nicotínicos/efeitos dos fármacos , Mordeduras de Serpentes/metabolismo , Venenos de Serpentes/toxicidade , Serpentes/metabolismo , Animais , Sítios de Ligação , Resistência a Medicamentos/genética , Glicosilação , Mutação , Junção Neuromuscular/metabolismo , Junção Neuromuscular/fisiopatologia , Neurotoxinas/metabolismo , Antagonistas Nicotínicos/metabolismo , Filogenia , Ligação Proteica , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Mordeduras de Serpentes/fisiopatologia , Venenos de Serpentes/metabolismo , Especificidade da Espécie
4.
Toxins (Basel) ; 11(10)2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31623073

RESUMO

The binding of compounds to nicotinic acetylcholine receptors is of great interest in biomedical research. However, progress in this area is hampered by the lack of a high-throughput, cost-effective, and taxonomically flexible platform. Current methods are low-throughput, consume large quantities of sample, or are taxonomically limited in which targets can be tested. We describe a novel assay which utilizes a label-free bio-layer interferometry technology, in combination with adapted mimotope peptides, in order to measure ligand binding to the orthosteric site of nicotinic acetylcholine receptor alpha-subunits of diverse organisms. We validated the method by testing the evolutionary patterns of a generalist feeding species (Acanthophis antarcticus), a fish specialist species (Aipysurus laevis), and a snake specialist species (Ophiophagus hannah) for comparative binding to the orthosteric site of fish, amphibian, lizard, snake, bird, marsupial, and rodent alpha-1 nicotinic acetylcholine receptors. Binding patterns corresponded with diet, with the Acanthophis antarcticus not showing bias towards any particular lineage, while Aipysurus laevis showed selectivity for fish, and Ophiophagus hannah a selectivity for snake. To validate the biodiscovery potential of this method, we screened Acanthophis antarcticus and Tropidolaemus wagleri venom for binding to human alpha-1, alpha-2, alpha-3, alpha-4, alpha-5, alpha-6, alpha-7, alpha-9, and alpha-10. While A. antarcticus was broadly potent, T. wagleri showed very strong but selective binding, specifically to the alpha-1 target which would be evolutionarily selected for, as well as the alpha-5 target which is of major interest for drug design and development. Thus, we have shown that our novel method is broadly applicable for studies including evolutionary patterns of venom diversification, predicting potential neurotoxic effects in human envenomed patients, and searches for novel ligands of interest for laboratory tools and in drug design and development.


Assuntos
Receptores Nicotínicos/metabolismo , Venenos de Serpentes , Animais , Sítios de Ligação , Aves , Colubridae , Elapidae , Ensaios de Triagem em Larga Escala , Humanos , Ligantes , Lagartos , Marsupiais , Ophiophagus hannah , Peptídeos/metabolismo , Filogenia , Roedores , Especificidade da Espécie
5.
Bioinorg Chem Appl ; 2017: 4101735, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28373829

RESUMO

Although nanoparticles (NPs) have made incredible progress in the field of nanotechnology and biomedical research and their applications are demanded throughout industrial world particularly over the past decades, little is known about the fate of nanoparticles in ecosystem. Concerning the biosafety of nanotechnology, nanotoxicity is going to be the second most priority of nanotechnology that needs to be properly addressed. This review covers the chemical as well as the biological concerns about nanoparticles particularly titanium dioxide (TiO2) NPs and emphasizes the toxicological profile of TiO2 at the molecular level in both in vitro and in vivo systems. In addition, the challenges and future prospects of nanotoxicology are discussed that may provide better understanding and new insights into ongoing and future research in this field.

6.
J Phys Ther Sci ; 28(10): 2942-2949, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27821967

RESUMO

[Purpose] The present study aimed to determine the changes in physical and balance performance following exercise-induced muscle damage using a sport-specific protocol. [Subjects and Methods] Fifteen collegiate soccer players were asked to perform a sport-specific sprint protocol to induce muscle damage. The markers of muscle damage (soreness, range of motion, limb girth, muscle strength, creatine kinase and lactate dehydrogenase), physical performance (speed, agility and power) and balance (static and dynamic balance) were assessed at baseline and 24, 48 and 72 hours following the sprint protocol. [Results] All variables, including the markers of muscle damage, physical performance and balance showed a significant difference when assessed at the 4 time points. [Conclusion] The study demonstrated that both the physical and balance performance were affected following repeated sprint protocol in soccer players. It is recommended the balance performance of an athlete be continually assessed following exercise-induced muscle damage so as to determine the appropriate return to sport decision thereby, minimizing the risk of further injury.

7.
J Infect Dis ; 210 Suppl 1: S152-61, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25316830

RESUMO

Pakistan is one of 3 countries where transmission of indigenous wild poliovirus (WPV) has never been interrupted. Numbers of confirmed polio cases have declined by >90% from preeradication levels, although outbreaks occurred during 2008-2013. During 2012 and 2013, 58 and 93 WPV cases, respectively, were reported, almost all of which were due to WPV type 1. Of the 151 WPV cases reported during 2012-2013, 123 (81%) occurred in the conflict-affected Federally Administered Tribal Areas (FATA) and in security-compromised Khyber Pakhtunkhwa province. WPV type 3 was isolated from only 3 persons with polio in a single district in 2012. During August 2012-December 2013, 62 circulating vaccine-derived poliovirus type 2 cases were detected, including 40 cases (65%) identified in the FATA during 2013. Approximately 350 000 children in certain districts of the FATA have not received polio vaccine during supplementary immunization activities (SIAs) conducted since mid-2012, because local authorities have banned polio vaccination. In other areas of Pakistan, SIAs have been compromised by attacks targeting polio workers, which started in mid-2012. Further efforts to reach children in conflict-affected and security-compromised areas will be necessary to prevent reintroduction of WPV into other areas of Pakistan and other parts of the world.


Assuntos
Erradicação de Doenças , Poliomielite/epidemiologia , Poliomielite/prevenção & controle , Poliovirus/isolamento & purificação , Adolescente , Criança , Pré-Escolar , Surtos de Doenças , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Paquistão/epidemiologia , Poliovirus/classificação , Vacinas contra Poliovirus/administração & dosagem , Vacinação/estatística & dados numéricos
8.
Gene ; 550(1): 74-80, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25111117

RESUMO

To study the life processes of all eukaryotes, yeast (Saccharomyces cerevisiae) is a significant model organism. It is also one of the best models to study the responses of genes at transcriptional level. In a living organism, gene expression is changed by chemical stresses. The genes that give response to chemical stresses will provide good source for the strategies in engineering and formulating mechanisms which are chemical stress resistant in the eukaryotic organisms. The data available through microarray under the chemical stresses like lithium chloride, lactic acid, weak organic acids and tomatidine were studied by using computational tools. Out of 9335 yeast genes, 388 chemical stress responding genes were identified and characterized under different chemical stresses. Some of these are: Enolases 1 and 2, heat shock protein-82, Yeast Elongation Factor 3, Beta Glucanase Protein, Histone H2A1 and Histone H2A2 Proteins, Benign Prostatic Hyperplasia, ras GTPase activating protein, Establishes Silent Chromatin protein, Mei5 Protein, Nondisjunction Protein and Specific Mitogen Activated Protein Kinase. Characterization of these genes was also made on the basis of their molecular functions, biological processes and cellular components.


Assuntos
Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Compostos Inorgânicos/farmacologia , Compostos Orgânicos/farmacologia , Saccharomyces cerevisiae/genética , Estresse Fisiológico/genética , Simulação por Computador , Ontologia Genética , Genes Fúngicos/genética , Ácido Láctico/farmacologia , Cloreto de Lítio/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas de Saccharomyces cerevisiae/genética , Tomatina/análogos & derivados , Tomatina/farmacologia , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética
9.
AAPS PharmSciTech ; 14(2): 558-68, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23483431

RESUMO

Three new solvates [mono-dimethyl sulfoxide (mono-DMSO), mono-dimethyl acetamide (mono-DMA) and mono-dimethyl formamide (mono-DMF)] of 10-Deacetyl baccatin III, were generated by slow evaporation in DMSO, DMF, and DMSO/DMA (1:1) solvent systems respectively. Two concomitant forms mono-DMSO(a new form) and di-DMSO (a known form) were obtained in the DMSO solvent system. Yet two other concomitant forms mono-DMA (a new form) and di-DMSO (a known form) were obtained in DMSO/DMA (1:1) solvent system. A fourth solvate mono-DMF (a new form) was crystallized in unimolar ratio using DMF as a solvent. These solvates were characterized using powder X-ray diffraction, differential scanning calorimeter, thermogravimetric analysis (TGA), and spectroscopic [(13)C solid-state nuclear magnetic spectroscopy, solution (1)H NMR, and Fourier transform infrared] techniques. The interactions between host and guest molecules were elucitated by single-crystal X-ray diffraction data. In all the cases, guest molecules are connected to the host molecules by O-H∙∙∙O hydrogen bonds. A remarkable difference in the desolvation onset temperatures of di- and mono-DMSO solvates was observed which was also featured by a corresponding weight loss during TGA analysis.


Assuntos
Antineoplásicos Fitogênicos/química , Taxoides/química , Acetamidas/química , Varredura Diferencial de Calorimetria , Química Farmacêutica , Cristalização , Cristalografia por Raios X , Dimetil Sulfóxido/química , Dimetilformamida/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Difração de Pó , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Tecnologia Farmacêutica/métodos , Temperatura , Termogravimetria
10.
J Oral Maxillofac Res ; 4(1): e2, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24422025

RESUMO

OBJECTIVES: Head and neck/oral cancer, predominantly head and neck squamous cell carcinoma (HNSCC), is the sixth most common cancer in the world. While substantial advances have been made to define the genomic alterations associated with head and neck/oral cancer, most studies are focused on protein coding genes. The aim of this article is to review the current literature on identified genomic aberrations of non-coding genes (e.g., microRNA) in head and neck/oral cancer (HNOC), and their contribution to the initiation and progression of HNOC. MATERIAL AND METHODS: A comprehensive review of the available literature relevant to microRNA deregulation in HNSCC/HNOC, was undertaken using PubMed, Medline, Scholar Google and Scopus. Keywords for the search were: microRNA and oral cancer, microRNA and squamous cell carcinoma, microRNA deregulation and oral cancer, microRNA and carcinogenesis in the head and neck/oral cavity. Only full length articles in the English language were included. RESULTS: We recently identified a panel of microRNA deregulations that were consistently observed in HNSCC [Chen et al., Oral Oncol. 2012;48(8):686-91], including 7 consistently up-regulated microRNAs (miR-21, miR-7, miR-155, miR-130b, miR-223, miR-34b), and 4 consistently down-regulated microRNAs (miR-100, miR-99a, miR-125b, miR-375). In this review, we will first provide an overview on microRNA and HNSCC. We will then provide a comprehensive review on the roles of microRNA deregulations in HNSCC. The functional significance of the identified HNSCC-associated microRNAs and a number of other relevant microRNAs (e.g., miR-138, miR-98, miR-137, miR-193a and miR-218) will be discussed in detail. CONCLUSIONS: Based on current literature, microRNA deregulation plays a major role in head and neck/oral cancer.

11.
J Pharm Biomed Anal ; 58: 27-33, 2012 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-22014653

RESUMO

A simple and rapid capillary zone electrophoretic method was developed for determining dimethyl sulfate a possible human carcinogen and mutagen and chloroacetyl chloride a potential genotoxic agent at trace levels in pharmaceutical drug substances by indirect photometric detection. A systematic screening of various anionic probes was performed to obtain the best separation conditions and sensitivity. High sensitivities with low quantification and detection levels were achieved for dimethylsulfate and chloroacetyl chloride using a background electrolyte (BGE) containing 5 mM pyridine dicarboxylic acid as the probe ion. The method is specific, precise and accurate for the two genotoxins. The optimized method was validated for specificity, precision, linearity, accuracy and stability in solution. Calibration curves were linear (R>0.999) for both dimethylsulfate and chloroacetyl chloride in the range LOQ - 300% of nominal concentrations. The CE method was effectively implemented for estimating dimethylsulfate and chloroacetyl chloride in two different active pharmaceutical ingredients (APIs).


Assuntos
Acetatos/análise , Carcinógenos/análise , Eletroforese Capilar/métodos , Mutagênicos/análise , Preparações Farmacêuticas/análise , Ésteres do Ácido Sulfúrico/análise , Acetatos/química , Calibragem , Carcinógenos/química , Eletrólitos/química , Mutagênicos/química , Preparações Farmacêuticas/química , Sensibilidade e Especificidade , Ésteres do Ácido Sulfúrico/química
12.
J Pharm Biomed Anal ; 59: 162-6, 2012 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-22030076

RESUMO

A series of novel 6-fluoro1,4-dihydro-4-oxo-3-quinoline carboxylic acid dimers were synthesized as potential antibacterial agents from commercially available substituted fluorobenzoic acids. A stability indicating HPLC method was developed to determine these novel fluoroquinolone dimers using a systematic method development approach. Samples were subjected to stress conditions of hydrolysis, oxidation, photolysis and thermal degradation; and analyzed to demonstrate the specificity and stability indicating ability of the developed method. The precision for all four fluoroquinolone dimers was within 2.0% RSD. Calibration curves were linear (LOQ, 150%), with regression coefficients >0.99 for all dimers. The method was conveniently applied for determining purity and assay of these four novel fluoroquinolone dimers.


Assuntos
Antibacterianos/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Fluoroquinolonas/isolamento & purificação , Antibacterianos/síntese química , Antibacterianos/química , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/normas , Dimerização , Estabilidade de Medicamentos , Fluoroquinolonas/síntese química , Fluoroquinolonas/química , Limite de Detecção , Modelos Lineares , Estrutura Molecular , Padrões de Referência , Reprodutibilidade dos Testes , Soluções
13.
J Coll Physicians Surg Pak ; 17(9): 558-61, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17903406

RESUMO

OBJECTIVE: To evaluate the frequency of short-term pulmonary complications in the patients undergoing various head and neck cancer surgeries in our setup and to assess possible risk factors responsible for these complications. STUDY DESIGN: Quasi experimental study. PLACE AND DURATION OF STUDY: Department of ENT, Head and Neck Surgery, Combined Military Hospital, Rawalpindi from July 2005 till August 2006. PATIENTS AND METHODS: Seventy patients of age group 20 to 80 years, regardless of gender, treated surgically for head and neck cancers were enrolled. Main outcome measures included development of pulmonary complications following 15 days of oncological surgery. The complications studied were pneumothorax, bronchopneumonia, atelectasis, pulmonary embolism and cardiopulmonary arrest. RESULTS: A total of 24.28% patients suffered from postoperative pulmonary complications; 17.14% developed bronchopneumonia, 5.71% pulmonary embolism, and 1.42% went into cardiopulmonary arrest, none developed pneumothorax or pulmonary atelectasis. A significant correlation of postoperative bronchopneumonia was seen with heavy smoking and assisted ventilation. Pulmonary embolism was associated with extended assisted ventilation and prolonged surgery. Cardiopulmonary arrest was associated with comorbidity and assisted ventilation after surgery. CONCLUSION: The frequency of bronchopneumonia supersedes all of the postoperative pulmonary complications in head and neck oncological surgery. Patients at risk of developing postoperative complications are heavy smokers, diabetics, those undergoing prolonged surgery, tracheostomy, and extended assisted ventilation.

14.
J Coll Physicians Surg Pak ; 17(2): 94-7, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17288855

RESUMO

OBJECTIVE: To determine the etiology and pattern of maxillofacial injuries in the Armed Forces of Pakistan in terms of anatomical distribution of injuries. DESIGN: A descriptive study. PLACE AND DURATION OF STUDY: January 2001 to Jan 2004 at the Oral and Maxillofacial Surgery Department, AFID, Rawalpindi. PATIENTS AND METHODS: Three hundred consecutive patients of Armed Forces of Pakistan with maxillofacial injuries reporting to AFID and admitted to the hospital or treated as out-patients in the oral surgery clinic, were included in this study. Isolated nasal bone and frontal sinus fractures were excluded from the study. Anatomical distribution, frequency and etiology of fractures, rank at job and occupational as well as personal hobbies were recorded. Descriptive analyses were used to determine mean, standard deviation, percentage and range values. RESULTS: The most frequent bone fractured was the mandible, which accounted for 159 cases (53%). The zygomatic complex was fractured in 51 cases (17%), the maxilla in 12 cases (4 %), and the alveolar process in 21 cases (7%). The most common cause was road traffic accident (168 cases; 56%), followed by accidental fall (69 cases; 23%), gunshot injuries (27 cases; 9%), sports related injuries (15 cases; 5%), and injury associated with a fight (12 cases; 4%); there were only 9 cases of animals related injuries (3%). CONCLUSION: In this series, mandible was the most commonly fractured facial bone, while road traffic accident was the most common etiological factor. Results could be influenced by the personal and working environment.


Assuntos
Traumatismos Maxilofaciais/epidemiologia , Medicina Militar , Militares/estatística & dados numéricos , Acidentes de Trânsito/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Causalidade , Feminino , Humanos , Incidência , Masculino , Fraturas Mandibulares/epidemiologia , Fraturas Mandibulares/etiologia , Fraturas Maxilares/epidemiologia , Fraturas Maxilares/etiologia , Traumatismos Maxilofaciais/classificação , Traumatismos Maxilofaciais/etiologia , Paquistão/epidemiologia , Fatores de Risco
15.
J Chromatogr B Analyt Technol Biomed Life Sci ; 846(1-2): 119-23, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-16962393

RESUMO

A stereospecific HPLC method for separation of Frovatriptan enantiomers in bulk drug and pharmaceutical formulations was developed and validated on a normal-phase amylose derivertized chiral column. The effects of the organic modifiers namely 2-propanol, ethanol and diethyl amine (DEA) in the mobile phase were optimized to obtain the best enantiomeric separation. Calibration curves were linear over the range of 200-6150 ng/mL, with a regression coefficient (R(2)) of 0.9998. The limit of detection (LOD) and limit of quantification (LOQ) were 65 ng/mL and 200 ng/mL, respectively. The method was accurate and precise and suitable for the intended purpose. Analysis results were compared with the results obtained by using a validated chiral CE method and found to be in very good agreement. This method can be successfully applied to the enantiomeric purity analysis of Frovatriptan in pharmaceutical bulk drug samples and formulations.


Assuntos
Amilose/química , Carbazóis/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Agonistas do Receptor de Serotonina/isolamento & purificação , Triptaminas/isolamento & purificação , Carbazóis/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Agonistas do Receptor de Serotonina/química , Estereoisomerismo , Triptaminas/química
16.
J Pharm Biomed Anal ; 41(4): 1447-52, 2006 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-16672183

RESUMO

A cyclodextrin modified capillary zone electrophoretic method has been developed for the evaluation of chiral purity of Frovatriptan using sulfobutyl ether beta cyclodextrin (SB-beta-CD) as the chiral selector. The method is highly specific, accurate and reproducible. The method was optimized with a systematic method development approach by optimizing the pH of electrolyte, attempting the separation in different classes of chiral selectors and modifying parameters such as cyclodextrin concentration and the organic modifier type and concentration. The optimized method was validated for specificity, precision, linearity, accuracy and stability in solution using Imidazole as the internal standard. The limit of detection (LOD) and limit of quantification (LOQ) were 1.0 microg/mL and 5.0 microg/mL respectively for each isomer. The method was applied for estimating the chiral purity of various batches of Frovatriptan.


Assuntos
Carbazóis/isolamento & purificação , Eletroforese Capilar/métodos , Agonistas do Receptor de Serotonina/isolamento & purificação , Triptaminas/isolamento & purificação , Ciclodextrinas , Concentração de Íons de Hidrogênio , Estereoisomerismo
17.
Endocr Pathol ; 9(1): 353-361, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-12114784

RESUMO

Hemorrhagic adrenal pseudocysts are uncommon nonneoplastic lesions that have been reported as secondary to intraparenchymal hemorrhage or alternatively related to endothelial (vascular) cysts. Ultrastructural and ammunohistochemical evidence in support of the latter has been presented, but the exact nature of hemorrhagic adrenal pseudocysts remains poorly defined. We evaluated six surgical specimens of hemorrhagic adrenal pseudocysts using immunohistochemical staining for CD31 and CD34, as well as conventional histochemistry. All six cases had hemorrhagic contents within a wall of variable thickness possessing focal areas of linear, disrupted elastin, and smooth muscle. Three cases demonstrated extensive thrombosis with organization, including papillary endothelial hyperplasia, simulating angiosarcoma. In these cases, CD3I and CD34 staining decorated areas of papillary endothelial hyperplasia as well as foci of the internal cyst lining, whereas the other cases were negative for both antibodies. Of interest is the history of FNA prior to surgical resection in three cases of hemorrhagic adrenal pseudocysts, two of which showed papillary endothelial hyperplasia. The presence of papillary endothelial hyperplasia and our immunohistochemical findings support the conclusion that adrenal pseudocysts are posthemorrhagic and derive from vascular disruption. Furthermore, FNA or other interventional studies may be associated with papillary endothelial hyperplasia in hemorrhagic adrenal pseudocysts.

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