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Genetic disorders (GDs) are challenging to treat owing to a lack of optimal treatment regimens and intricate and often difficult-to-understand underlying biological processes. Limited therapeutic approaches, which mostly provide symptomatic relief, are available. To date, a limited number of peptide-based drugs for the treatment of GDs are available, and several candidates are under clinical study. This review provides mechanistic insights into GDs and potential target areas where peptide-based drugs are beneficial. In addition, it emphasizes the usefulness of peptides as carriers for gene delivery, biomarkers for mutation detection and peptide-based vaccines for treating GDs.
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BACKGROUND: A cultural preference for sons has been well documented in India, resulting in skewed sex ratios, especially exhibited in northwest India. Previous research has shown that family sex composition is associated with family planning (FP) use and couples' desire for more children. This study examines family sex composition and fertility and FP behaviors in urban Uttar Pradesh, India; little work has examined these issues in urban settings where family sizes are smaller and FP use is common. METHODS: Data for this analysis comes from a 2010 representative survey of married, non-pregnant fecund women aged 15-49 from six cities in Uttar Pradesh, India. Multivariate analyses are used to examine the association between family sex composition and fertility desires and FP use. RESULTS: The multivariate results indicate that family sex composition is associated with fertility desires and FP use. Women without living children and without at least one child of each sex are significantly less likely to want no more children and women with both sons and daughters but more sons are significantly more likely to want no more children as compared to women that have both sons and daughters but more daughters. Women with no living children and women with daughters but no sons are less likely to be modern FP users than nonusers whereas women with both sons and daughters but more sons are more likely to be modern FP users than nonusers as compared to women with both sons and daughters but more daughters. CONCLUSIONS: These findings confirm that family sex composition affects fertility behavior and also reveals that preference for sons persists in urban Uttar Pradesh. These results underscore the importance of programs and policies that work to enhance the value of girl children.
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Comportamento Contraceptivo/etnologia , Características da Família , Serviços de Planejamento Familiar/estatística & dados numéricos , Adolescente , Adulto , Criança , Mortalidade da Criança , Feminino , Fertilidade , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Áreas de Pobreza , Razão de Masculinidade , População UrbanaRESUMO
The dawn of targeted degradation using proteolysis-targeting chimeras (PROTACs) against recalcitrant proteins has prompted numerous efforts to develop complementary drugs. Although many of these are specifically directed against undruggable proteins, there is increasing interest in small molecule-based PROTACs that target intracellular pathways, and some have recently entered clinical trials. Concurrently, small molecule-based PROTACs that target protumorigenic pathways in cancer cells, the tumor microenvironment (TME), and angiogenesis have been found to have potent effects that synergize with the action of antibodies. This has led to the augmentation of PROTACs with variable substitution patterns. Several combinations with small molecules targeting undruggable proteins are now under clinical investigation. In this review, we discuss the recent milestones achieved as well as challenges encountered in this area of drug development, as well as our opinion on the best path forward.
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Proteínas , Proteólise , Proteínas/metabolismoRESUMO
Respiratory diseases account for unprecedented mortality owing to a lack of personalized or insufficient therapeutic interventions. Fostering pulmonary research into managing pulmonary threat requires a potential alternative approach that can mimick the in vivo complexities of the human body. The in vitro miniaturized bionic simulation of the lung holds great potential in the quest for a successful therapeutic intervention. This review discusses the emerging roles of lung-on-chip microfluidic simulator devices in fostering translational pulmonary drug discovery and personalized medicine. This review also explicates how the lung-on-chip model emulates the breathing patterns, elasticity, and vascularization of lungs in creating a 3D pulmonary microenvironment.
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Descoberta de Drogas , Pulmão , Humanos , Sistemas de Liberação de Medicamentos , Microfluídica , Dispositivos Lab-On-A-ChipRESUMO
Malaria remains a major vector borne disease claiming millions of lives worldwide due to infections caused by Plasmodium sp. Discovery and development of antimalarial drugs have previously been dominated majorly by single drug therapy. The malaria parasite has developed resistance against first line and second line antimalarial drugs used in the single drug therapy. This has drawn attention to find ways to alleviate the disease burden supplanted by combination therapy with multiple drugs to overcome drug resistance. Emergence of resistant strains even against the combination therapy has now mandated the revision of the current antimalarial pharmacotherapy. Research efforts of the past decade led to the discovery and identification of several new structural classes of antimalarial agents with improved biological attributes over the older ones. The following is a comprehensive review, addressed to the new structural classes of heterocyclic and natural compounds that have been identified during the last decade as antimalarial agents. Some of the classes included herein contain one or more pharmacophores amalgamated into a single bioactive scaffold as antimalarial agents, which act upon the conventional and novel targets.
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Antimaláricos , Malária , Plasmodium , Antimaláricos/química , Resistência a Medicamentos , Humanos , Malária/tratamento farmacológico , Plasmodium falciparumRESUMO
Objective: To gain better insight into the extent of secondary bacterial and fungal infections in hospitalized patients in India, and to assess how these alter the course of coronavirus disease 2019 (COVID-19) so that control measures can be suggested. Methods: In this retrospective, multicentre study, the data of all patients who tested positive for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) on reverse transcriptase polymerase chain reaction (RT-PCR), admitted to hospital between March 2020 and July 2021, were accessed from the electronic health records of a network of 10 hospitals across five states in North India. Results: Of 19,852 patients testing positive for SARS-CoV-2 on RT-PCR and admitted to the study hospitals during the study period, 1940 (9.8%) patients developed secondary infections (SIs). Patients with SIs were, on average, 8 years older than patients without SIs (median age 62.6 vs 54.3 years; P<0.001). The risk of SIs was significantly (P<0.001) associated with age, severity of disease at admission, diabetes, admission to the intensive care unit (ICU), and ventilator use. The most common site of infection was urine (41.7%), followed by blood (30.8%) and sputum/bronchoalveolar lavage/endotracheal fluid (24.8%); the least common was pus/wound discharge (2.6%). Gram-negative bacilli (GNB) were the most common organisms (63.2%), followed by Gram-positive cocci (GPC) (19.6%) and fungi (17.3%). Most patients with SIs were on multiple antimicrobials. The most commonly used antibiotics against GNB were beta-lactam/beta-lactamase inhibitors (76.9%), carbapenems (57.7%), cephalosporins (53.9%), and antibiotics against carbapenem-resistant Enterobacteriaceae (47.1%). Empirical use of antibiotics against GPC was seen in 58.9% of patients with SIs, and empirical use of antifungals was observed in 56.9% of patients with SIs. The average length of hospital stay for patients with SIs was almost twice as long as that of patients without SIs (median 13 vs 7 days). Overall mortality among patients with SIs (40.3%) was more than eight times higher than that among patients without SIs (4.6%). Only 1.2% of patients with SIs with mild COVID-19 at admission died, compared with 17.5% of those with moderate COVID-19 at admission and 58.5% of those with severe COVID-19 at admission (P<0.001). The mortality rate was highest in patients with bloodstream infections (49.8%), followed by those with hospital-acquired pneumonia (47.9%), urinary tract infections (29.4%), and skin and soft tissue infections (29.4%). The mortality rate in patients with diabetes with SIs was 45.2%, compared with 34.3% in those without diabetes (P<0.001). Conclusions: SIs complicate the course of patients hospitalized with COVID-19. These patients tend to have a much longer hospital stay, a higher requirement for oxygen and ICU care, and a significantly higher mortality rate compared with those without SIs. The groups most vulnerable to SIs are patients with more severe COVID-19, elderly patients and patients with diabetes. Judicious empirical use of combination antimicrobials in these groups of vulnerable patients can save lives. It is desirable to have region- or country-specific guidelines for appropriate use of antibiotics and antifungals to prevent their overuse.
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In continuing our search of potent antimalarials based on 8-aminoquinoline structural framework, three series of novel bis(8-aminoquinolines) using convenient one to four steps synthetic procedures were synthesized. The bisquinolines were evaluated for in vitro antimalarial (Plasmodiumfalciparum), antileishmanial (Leishmaniadonovani), antimicrobial (a panel of pathogenic bacteria and fungi), cytotoxicity, ß-hematin inhibitory and methemoglobin (MetHb) formation activities. Several compounds exhibited superior antimalarial activities compared to parent drug primaquine. Selected compounds (44, 61 and 79) when tested for in vivo blood-schizontocidal antimalarial activity (Plasmodiumberghei) displayed potent blood-schizontocial activities. The bisquinolines showed negligible MetHb formation (0.2-1.2%) underlining their potential in the treatment of glucose-6-phosphate dehydrogenase deficient patients. The bisquinoline analogues (36, 73 and 79) also exhibited promising in vitro antileishmanial activity, and antimicrobial activities (43, 44 and 76) against a panel of pathogenic bacteria and fungi. The results of this study provide evidence that bis(8-aminoquinolines), like their bis(4-aminoquinolines) and artemisinin dimers counterparts, are a promising class of antimalarial agents.
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Aminoquinolinas/farmacologia , Anti-Infecciosos/farmacologia , Antiprotozoários/farmacologia , Hemeproteínas/antagonistas & inibidores , Metemoglobina/biossíntese , Aminoquinolinas/síntese química , Animais , Anti-Infecciosos/química , Antiprotozoários/química , HumanosRESUMO
Malaria is a major public health problem mainly due to the development of resistance by the most lethal causative parasitic species, Plasmodium falciparum to the mainstay drugs like chloroquine. New drugs with unique structures and mechanism of action are urgently required to treat sensitive and drug-resistant strains of malaria. Historically, compounds containing novel structure from natural origin represent a major source for the discovery and development of new drugs for several diseases. This review presents recent advances in antimalarial drug discovery from natural sources, including plant extracts, and compounds isolated from plants, bacteria, fungi and marine organisms. These compounds offer new and novel scaffolds for development as antimalarials. The literature from 1998 to October 2008 is reviewed. The review present literature compilation from plant and marine extracts, alkaloids (naphthylisoquinolines, bisbenzylisoquinolines, protoberberines and aporphines, indoles, manzamines, and miscellaneous alkaloids) terpenes (sesquiterpenes, triterpenes, diterpenes, and miscellaneous terpenes) quassinoids, flavonoids, limonoids, chalcones, peptides, xanthones, quinones and coumarines, and miscellaneous antimalarials from nature. The review also provides an outlook to recent semisynthetic approaches to antimalarial drugs discovered from natural sources.
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Antimaláricos/química , Antimaláricos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sequência de Aminoácidos , Animais , Antimaláricos/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Descoberta de Drogas , Dados de Sequência Molecular , Extratos Vegetais/isolamento & purificação , Plasmodium/efeitos dos fármacosRESUMO
In the search of therapeutic agents for emerging drug-resistant parasites, the synthesis of newer classes of 8-quinolinamines has emerged as a successful chemotherapeutic approach. We report synthesis of 8-quinolinamines bearing 5-alkoxy, 4-methyl, and 2-tert-butyl groups in the quinoline framework and their amino acid conjugates as broad-spectrum anti-infectives. 8-Quinolinamines exhibited potent in vitro antimalarial activity [IC50 = 20-4760 ng/mL (drug-sensitive Plasmodium falciparum D6 strain) and IC50 = 22-4760 ng/mL (drug-resistant P. falciparum W2 strain)]. The most promising analogues have cured all animals at 25 mg/kg/day against drug-sensitive Plasmodium berghei and at 50 mg/kg/day against multidrug-resistant Plasmodium yoelii nigeriensis infections in Swiss mice. The in vitro antileishmanial activities (IC50 = 0.84-5.0 µg/mL and IC90 = 1.95-7.0 µg/mL) comparable to standard drug pentamidine were exhibited by several of the synthesized 8-quinolinamines. At the same time, very promising antifungal activities (Candida albicans-IC50 = 4.93-19.38 µg/mL; Candida glabrata-IC50 = 3.96-19.22 µg/mL; Candida krusei-IC50 = 2.89-18.95 µg/mL; Cryptococcus neoformans-IC50 = 0.67-18.64 µg/mL; and Aspergillus fumigatus-IC50 = 6.0-19.32 µg/mL) and antibacterial activities (Staphylococcus aureus-IC50 = 1.33-18.9 µg/mL; methicillin-resistant S. aureus-IC50 = 1.38-15.34 µg/mL; and Mycobacterium intracellulare-IC50 = 3.12-20 µg/mL) were also observed. None of the 8-quinolinamines exhibited cytotoxicity and therefore are a promising structural class of compounds as antiparasitic and antimicrobials.
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United Arab Emirates (UAE) has a high prevalence of hypovitaminosis D. Not much data are available regarding the prevalence of Vitamin D deficiency among multiethnic UAE adult population. (1) To determine the prevalence of hypovitaminosis D in multiethnic UAE population (2) To compare the Vitamin D status in Arab and non-Arab population (3) To identify the demographic variables associated with hypovitaminosis D. It was a retrospective study conducted at a secondary care hospital. Electronic case records of all the subjects who had checked their Vitamin D levels during the time period of May 2010-October 2012 were considered for the study. Vitamin D severe deficiency, deficiency, insufficiency, and sufficiency were defined as serum 25-hydroxy Vitamin D (25(OH)D) levels < 10 ng/mL, 10-20 ng/mL, 21-30 ng/mL, and > 30 ng/mL, respectively. A total 425 subjects were included for the data analysis. Vitamin D deficiency was diagnosed in 208 (48.9%) subjects followed by severe Vitamin D deficiency and insufficiency in 141 (33.2%) and 63 (14.8%) subjects, respectively. The overall prevalence of hypovitaminosis D was 96.9%. Negative association (r = -0.196, P < 0.01) was observed between body mass index (BMI) and 25(OH)D levels. Ethnicity was not (P = 0.103) a predictor of 25(OH)D levels. Majority of our study subjects had Vitamin D deficiency. There was no substantial difference in 25(OH)D levels of different ethnic groups. Female gender, age, and BMI were the predictors 25(OH)D levels.
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BACKGROUND: Calcineurin (CaN) is an important serine-threonine phosphatase (PP2B), which plays a crucial role in calcium-calmodulin mediated signal transduction events. Calcineurin has been implicated in pathogenesis of various diseases cardiac hypertrophy, diabetic neuropathy and Alzheimer's, however its role in neoplasia remains unclear. RESULTS: In view of this we evaluated the calcineurin activity in serum and biopsy samples collected from women diagnosed with invasive squamous cell carcinoma of cervix. A significant reduction was observed in the calcineurin activity in cancer cervix patients compared to the control group. However the calcineurin activity remained unaltered in the cervical scrapes obtained from patients diagnosed with low-grade squamous intra epithelial lesions (LSIL). Interestingly the downregulation of calcineurin activity in squamous cell carcinomas was not accompanied by any significant change in DNA-binding affinity of the transcriptional factor NFAT (Nuclear Factor of Activated T-cells). All the squamous cell carcinoma samples used in the present study were positive for high-risk human papillomavirus (HPV) types. CONCLUSION: The present study demonstrates the downregulation of calcineurin activity in squamous cell carcinoma of cervix with high risk HPV infection. We conclude that perturbations in calcineurin-mediated pathway may be involved in development of cervical neoplasia.
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AIM: To assess the effects of early oral hydration after elective caesarian section. METHODS: Hundred women were selected from the maternity wards of LHMC and SSK Hospital, and alternately assigned into control and study groups of 50 each. Women with medical complications and antepartum haemorrhage were excluded. In the study group, oral hydration was started 6-h postextubation irrespective of presence of bowel sounds. Solid food was started after bowel sounds appeared. In the control group, traditional regime of oral hydration after the appearance of bowel sounds and then a gradual shift to the solids was adopted. The return of bowel activity, time of ambulating and complications were compared. RESULTS: Bowel sounds appeared in a significantly shorter duration of time in study group, the mean being 7.4 h as compared to 11.5 h in the control group. Passage of flatus and bowel evacuation was earlier in the study group (9.14 and 23.7 h, respectively) than in the control (19.9 and 32.3 h, respectively). Women ambulated faster in the study group than the control group (15 h versus 25 h, respectively). Mean oral fluid intake was much more and return to soft and then full diet was faster in the study group. Sixty percent women preferred early feeding to the traditional one. CONCLUSION: Early oral hydration in the postoperative period helps in the faster recovery of the patient by means of quicker return to normal feeding habits and early ambulation, the two main concerns of any surgeon before discharging the woman after caesarian section.
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Cesárea , Hidratação , Intestinos/fisiologia , Cuidados Pós-Operatórios , Auscultação , Dieta , Ingestão de Líquidos , Feminino , Flatulência , Humanos , Atividade Motora , Complicações Pós-Operatórias/epidemiologia , Gravidez , Fatores de TempoRESUMO
To eliminate an unwarranted metabolic pathway of the quinoline ring, a set of two compounds, where C-2 position of the antimalarial drug primaquine is blocked by metabolically stable bulky alkyl group are synthesized. Compound 2 [R = C(CH(3))(3)] of the series has produced excellent antimalarial efficacy against P. berghei and highly virulent multidrug-resistant P. yoelii nigeriensis strain in vivo. Compound 2 was also evaluated for methemoglobin (MetHb) toxicity. This study describes the discovery of a highly potent blood-schizontocidal antimalarial analogue 2, completely devoid of MetHb toxicity.
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Antimaláricos/síntese química , Metemoglobina/análise , Primaquina/análogos & derivados , Primaquina/síntese química , Animais , Antimaláricos/farmacologia , Antimaláricos/toxicidade , Malária/sangue , Malária/mortalidade , Malária/parasitologia , Camundongos , Plasmodium berghei/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Plasmodium yoelii/efeitos dos fármacos , Primaquina/farmacologia , Primaquina/toxicidade , Relação Estrutura-AtividadeRESUMO
Three new series of 8-aminoquinolines with modifications in the side-chain by conjugation with amino acids, dipeptides and pseudodipeptides have been synthesized. The synthesized compounds were tested for in vitro antimalarial activity against chloroquine-sensitive and chloroquine-resistant Plasmodium falciparum strains, in vitro cytotoxicity in mammalian kidney cells (Vero), in vitro antileishmanial activity against Leishmania donovani, in vitro antimicrobial activity and in vitro inhibition of ß-haematin formation. The promising compounds were also evaluated for in vivo blood-schizontocidal antimalarial activity against Plasmodium berghei infected mice. The analogues 55 and 101 produced highest antimalarial activities, in vitro. Analogues 52 and 59 exhibited promising antileishmanial and broad spectrum of antifungal activities, respectively.
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Aminoácidos/química , Aminoquinolinas/química , Aminoquinolinas/farmacologia , Técnicas de Química Sintética , Dipeptídeos/química , Hemeproteínas/antagonistas & inibidores , Peptidomiméticos/química , Aminoquinolinas/síntese química , Aminoquinolinas/toxicidade , Animais , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/toxicidade , Chlorocebus aethiops , Fungos/efeitos dos fármacos , Hemeproteínas/metabolismo , Leishmania donovani/efeitos dos fármacos , Camundongos , Plasmodium falciparum/efeitos dos fármacos , Células VeroRESUMO
2-tert-Butylprimaquine (NP-96) is a novel quinoline anti-malarial compound with superior therapeutic profile than primaquine (PQ). Moreover, it is the first 8-aminoquinoline that is established to be devoid of methemoglobin toxicity. The purpose of the present study was to investigate covalent adduct formation tendency of PQ, NP-96 and their phase I metabolites with glutathione (GSH) and N-acetylcysteine (NAc). For the same, the two compounds were incubated in human and rat liver microsomes in the presence of trapping agents and NADPH. In a control set, NADPH was excluded, while a blank was also studied that was devoid of both NADPH and microsomes. The components in the reaction mixtures were initially separated on a C-18 column (250 mm×4.6mm, 5 µm) using a mobile phase composed of acetonitrile and 10 mM ammonium acetate in a gradient mode. The samples were then subjected to LC-MS(n) and LC-HR-MS analyses, and data were collected in full scan MS, data dependent MS/MS, targeted MS/MS, neutral loss scan (NLS) and accurate mass (MS/TOF) modes. In a significant finding, both PQ and NP-96 themselves showed potential to bind covalently with GSH and NAc, as adducts were observed even in the control and blank incubations. Intense peaks corresponding to covalent adduct of mono-hydroxy metabolite of NP-96 with GSH and NAc were also detected in NADPH supplemented reaction solution.
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Acetilcisteína/química , Cromatografia Líquida de Alta Pressão/métodos , Glutationa/química , Primaquina/análogos & derivados , Primaquina/química , Espectrometria de Massas em Tandem/métodos , Acetilcisteína/metabolismo , Animais , Glutationa/metabolismo , Humanos , Microssomos Hepáticos/metabolismo , Primaquina/metabolismo , RatosRESUMO
The quinoline scaffold is prevalent in a variety of pharmacologically active synthetic and natural compounds. The discovery of chloroquine, the most famous drug containing this scaffold resulted in control and eradication of malaria for decades. The other known antimalarial drugs from the quinoline family include: quinine, amodiaquine, piperaquine, primaquine, and mefloquine. The drugs from this group mostly act during the blood stages of the parasite's life cycle but some like primaquine targets the tissue stages. This review provides a comprehensive literature compilation concerning the study of quinolines and also other heterocycles structurally similar to quinoline scaffold in the treatment of malaria. This review covers advances made in the last ten years and it is subdivided into eight sub-headings. It consists of discussion on the biological activities, structure-activity relationship, and potential biochemical pathways of 4-aminoquinolines, 4-anilinoquinolines, 8-aminoquinolines, quinolines from nature, quinolones, isoquinolines and tetrahydroquinolines, ring-modified quinolines, and miscellaneous quinolines.
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Antimaláricos/química , Antimaláricos/farmacologia , Quinolinas/química , Quinolinas/farmacologia , Animais , Humanos , Relação Estrutura-AtividadeRESUMO
An ultra-high performance liquid chromatographic tandem mass spectroscopy (UHPLC-MS/MS) method was developed and validated for the quantification of an investigational anti-malarial entity, 2-tert-butylprimaquine (NP-96), in rat plasma. Simple protein precipitation by acetonitrile was used for the sample preparation. Effective separation of NP-96, internal standard (IS) and matrix components were achieved on an UHPLC column (Hypersil Gold C18, 50mmx2.1mm, 1.9microm) using a mobile phase composed of acetonitrile and 20mM ammonium acetate, which was pumped in a gradient mode at a flow rate of 450microl/min. Selective reaction monitoring (SRM) was utilized for quantitation of the molecules. To increase sensitivity of the method, two ions of m/z 299 and m/z 231 were selected for NP-96, while IS was monitored for an ion of m/z 489. The method was validated according to FDA guideline on bioanalytical method validation and showed good compliance. The intra-day and inter-day precision expressed as R.S.D. was lower than 15% at all the tested quality control levels, including upper and lower limits of quantification. The calibration range was 2.5-500ng/ml. Total runtime for the method was 5min, which was suitable to produce high-throughput results for pharmacokinetic evaluation.
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Antimaláricos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Drogas em Investigação , Primaquina/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Animais , Antimaláricos/química , Antimaláricos/farmacocinética , Calibragem , Relação Dose-Resposta a Droga , Estabilidade de Medicamentos , Congelamento , Masculino , Estrutura Molecular , Primaquina/sangue , Primaquina/química , Primaquina/farmacocinética , Controle de Qualidade , Distribuição Aleatória , Ratos , Ratos Wistar , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Temperatura , Fatores de TempoRESUMO
Malaria caused by protozoa of the genus Plasmodium, because of its prevalence, virulence, and drug resistance, is the most serious and widespread parasitic disease encountered by mankind. The inadequate armory of drugs in widespread use for the treatment of malaria, development of strains resistant to commonly used drugs such as chloroquine, and the lack of affordable new drugs are the limiting factors in the fight against malaria. These factors underscore the continuing need of research for new classes of antimalarial agents, and a re-examination of the existing antimalarial drugs that may be effective against resistant strains. This review provides an in-depth look at the most significant progress made during the past 10 years in antimalarial drug development.
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Antimaláricos/química , Antimaláricos/uso terapêutico , Malária/tratamento farmacológico , Animais , Desenho de Fármacos , Resistência a Medicamentos , Humanos , Plasmodium/efeitos dos fármacos , Plasmodium/metabolismoRESUMO
Epigenetic events play a prominent role during cancer development. This is evident from the fact that almost all cancer types show aberrant DNA methylation. These abnormal DNA methylation levels are not restricted to just a few genes but affect the whole genome. Previous studies have shown genome-wide DNA hypomethylation and gene-specific hypermethylation to be a hallmark of most cancers. Molecules like DNA methyltransferase act as effectors of epigenetic reprogramming. In the present study we have examined the possibility that the reprogramming genes themselves undergo epigenetic modifications reflecting their changed transcriptional status during cancer development. Comparison of DNA methylation status between the normal and cervical cancer samples was carried out at the promoters of a few reprogramming molecules. Our study revealed statistically significant DNA methylation differences within the promoter of DNMT3L. A regulator of de novo DNA methyltransferases DNMT3A and DNMT3B, DNMT3L promoter was found to have lost DNA methylation to varying levels in 14 out of 15 cancer cervix samples analysed. The present study highlights the importance of DNA methylation profile at DNMT3L promoter not only as a promising biomarker for cervical cancer, which is the second most common cancer among women worldwide, but also provides insight into the possible role of DNMT3L in cancer development.
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DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , Epigênese Genética , Neoplasias do Colo do Útero/genética , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Feminino , Humanos , Proteínas Supressoras de Tumor/genética , Neoplasias do Colo do Útero/enzimologia , Neoplasias do Colo do Útero/patologia , Dedos de Zinco/genéticaRESUMO
We have recently reported that the attachment of a bulky metabolically stable tert-butyl group at the C-2 position of a quinoline ring in primaquine results in a tremendous improvement in the blood schizontocidal antimalarial activity of 8-quinolinamine. Because free heme released from hemoglobin catabolism in a malarial parasite is highly toxic, the parasite protects itself mainly by crystallization of heme into insoluble nontoxic hemozoin. We now demonstrate the ability of 2-tert-butylprimaquine to inhibit in vitro beta-hematin formation, to form a complex with heme with a stoichiometry of 1:1, and to enhance heme-induced hemolysis. The results described herein indicate that a major improvement in the blood-schizontocidal antimalarial activity of 2-tert-butylprimaquine might be due to a disturbance of heme catabolism pathway in the malarial parasite.