Atovaquone, chloroquine, primaquine, quinine and tetracycline: antiproliferative effects of relevant antimalarials on Neospora caninum / Atovaquona, cloroquina, primaquina, quinino e tetraciclina: efeitos antiproliferativos de antimaláricos relevantes em Neospora caninum

Abstract Neospora caninum is an apicomplexan parasite that causes abortion in cattle, resulting in significant economic losses. There is no commercial treatment for neosporosis, and drug repositioning is a fast strategy to test possible candidates against N. caninum. In this article, we describe the effects of atovaquone, chloroquine, quinine, primaquine and tetracycline on N. caninum proliferation. The IC50 concentrations in N. caninum were compared to the current information based on previous studies for Plasmodium and Toxoplasma gondii, correlating to the described mechanisms of action of each tested drug. The inhibitory patterns indicate similarities and differences among N. caninum, Plasmodium and T. gondii. For example, atovaquone demonstrates high antiparasitic activity in all the analyzed models, while chloroquine does not inhibit N. caninum. On the other hand, tetracycline is effective against Plasmodium and N. caninum, despite its low activity in T. gondii models. The repurposing of antimalarial drugs in N. caninum is a fast and inexpensive way to develop novel formulations using well-established compounds.

Resumo Neospora caninum é um parasita Apicomplexa relacionado a abortos no gado bovino, que resultam em impactos econômicos. Não há tratamento comercial para neosporosis e o reposicionamento de drogas indica uma estratégia rápida para testar candidatos anti-N. caninum. Neste artigo, são descritos os efeitos da atovaquona, cloroquina, quinino, primaquine e tetraciclina na proliferação de N. caninum. As concentrações IC50 em N. caninum foram comparadas com a informação disponível, baseada em estudos publicados previamente para Plasmodium e Toxoplasma gondii, incluindo a correlação com os mecanismos de ação descritos para cada droga testada. Os padrões de inibição indicam pontos de similaridades e diferenças entre N. caninum, Plasmodium e T. gondii. Por exemplo, a atovaquona demonstra uma alta atividade antiparasitária em todos os modelos testados, enquanto a cloroquina não inibe N. caninum. Por outro lado, a tetraciclina é efetiva contra Plasmodium e N. caninum, em contraste com a baixa atividade em modelos de T. gondii. O reposicionamento de drogas antimaláricas em N. caninum é uma forma rápida e de baixo custo para o desenvolvimento de novas formulações que usam compostos bem estabelecidos.

Hidroxicloroquina: Del fármaco de herencia Inca hasta la inmunología moderna / Hydroxychloroquine: Inca inheritance drug to modern immunology

Resumen La hidroxicloroquina es un antiguo fármaco proveniente del árbol de quino (Cinchona pubescens), a partir del componente químico alcaloide llamado quinina. Sus primeros usos se documentaron en el Imperio Inca del Perú. Se caracteriza por distintos efectos beneficiosos en enfermedades inmunológicas, al disminuir los procesos de autoinflamación y autoinmunidad persistente. Esta revisión se enfoca en describir los mecanismos inmunomoduladores de la hidroxicloroquina, así como los efectos del fármaco en algunas de las enfermedades autoinmunes más prevalentes: lupus eritematoso sistémico, artritis reumatoide, síndrome de Sjögren, vasculitis sistémicas, nefropatía por IgA, síndrome antifosfolípido, distintas enfermedades inmunológicas de la piel. También se revisarán los efectos adversos descritos para este fármaco, especialmente la toxicidad de retina, que es el más temido.

Abstract Hydroxychloroquine is an old drug derived from the quino tree (Cinchona pubescens), from the alkaloid chemical component called quinine. Its first uses trace back to the Inca empire of Peru. It is characterized by different beneficial effects in immunological diseases, decreasing the processes of autoinflammation and persistent autoimmunity. This review focuses on describing the immunomodulatory mechanisms of hydroxychloroquine as well as the effects of the drug on some of the most prevalent autoimmune diseases: systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, systemic vasculitis, IgA nephropathy, antiphospholipid syndrome, different skin-related autoimmune disorders. The main adverse effects will be revised, focusing in the retinal toxicity.

Effects of Intraduodenal Infusion of the Bitter Tastant, Quinine, on Antropyloroduodenal Motility, Plasma Cholecystokinin, and Energy Intake in Healthy Men

BACKGROUND/AIMS: Nutrient-induced gut hormone release (eg, cholecystokinin [CCK]) and the modulation of gut motility (particularly pyloric stimulation) contribute to the regulation of acute energy intake. Non-caloric bitter compounds, including quinine, have recently been shown in cell-line and animal studies to stimulate the release of gastrointestinal hormones by activating bitter taste receptors expressed throughout the gastrointestinal tract, and thus, may potentially suppress energy intake without providing additional calories. This study aims to evaluate the effects of intraduodenally administered quinine on antropyloroduodenal pressures, plasma CCK and energy intake. METHODS: Fourteen healthy, lean men (25 ± 5 years; BMI: 22.5 ± 2.0 kg/m²) received on 4 separate occasions, in randomized, double-blind fashion, 60-minute intraduodenal infusions of quinine hydrochloride at doses totaling 37.5 mg (“Q37.5”), 75 mg (“Q75”) or 225 mg (“Q225”), or control (all 300 mOsmol). Antropyloroduodenal pressures (high-resolution manometry), plasma CCK (radioimmunoassay), and appetite perceptions/gastrointestinal symptoms (visual analog questionnaires) were measured. Ad libitum energy intake (buffet-meal) was quantified immediately post-infusion. Oral quinine taste-thresholds were assessed on a separate occasion using 3-alternative forced-choice procedure. RESULTS: All participants detected quinine orally (detection-threshold: 0.19 ± 0.07 mmol/L). Intraduodenal quinine did not affect antral, pyloric or duodenal pressures, plasma CCK (pmol/L [peak]; control: 3.6 ± 0.4, Q37.5: 3.6 ± 0.4, Q75: 3.7 ± 0.3, Q225: 3.9 ± 0.4), appetite perceptions, gastrointestinal symptoms or energy intake (kcal; control: 1088 ± 90, Q37.5: 1057 ± 69, Q75: 1029 ±70, Q225: 1077 ± 88). CONCLUSION: Quinine, administered intraduodenally over 60 minutes, even at moderately high doses, but low infusion rates, does not modulate appetite-related gastrointestinal functions or energy intake.

Etude comparative des profils de dissolution in vitro de quinine sulfate générique et princeps en utilisant la Chromatographie Liquide Haute Performance

Introduction : La quinine est une molécule préconisée pour le traitement du paludisme dans les régions où les souches de P. falciparum sont poly-résistantes. Face à l'importante utilisation de ses médicaments génériques d'une part, et au fléau des médicaments de qualité inférieure d'autre part, il devient plus que nécessaire d'appuyer les données des tests physico-chimiques par celles de dissolution in vitro dont l'évaluation et la comparaison des cinétiques permettra de prédire le comportement in vivo du principe actif et par conséquent l'efficacité du médicament générique. L'objectif de la présente étude était de réaliser une étude comparative de la cinétique de dissolution d'un princeps et d'un générique à base de quinine comprimé 300 mg commercialisés à Kinshasa.Matériels et méthodes : L'étude a été réalisée en utilisant trois milieux de pH différents (1,2 - 4,5 - 6,8) tels que recommandés par l'Agence Européenne de Médicament et en se servant d'un appareil de dissolution, tandis que l'équipement de chromatographie liquide à haute performance couplée à un détecteur à barrette de diodes a été utilisé pour la quantification. La méthode statistique fit factor a été appliquée pour comparer les résultats de dosage de la quinine dans les trois milieux tout en ayant évalué le biais à différents temps de dissolution.Résultats : Les différents échantillons de médicaments générique et princeps ont été conformes quant à l'identification et au dosage de la quinine, par contre leurs cinétiques de dissolution étaient non-similaires.Discussion : Ceci pourrait avoir une influence sur l'efficacité du produit générique et la sécurité des consommateurs, dénotant l'importance d'examiner les profils de dissolution des génériques avant toute autorisation de mise sur le marché plus particulièrement dans les pays en voie de développement

Blackwater Fever Followed by Severe Falciparum Malaria in a Child

Blackwater fever is a serious clinical syndrome manifested by acute intravascular hemolysis, fever, and the passage of black or red urine, which is classically associated with falciparum malaria and irregular administration of quinine. In Korea, Plasmodium vivax is the only endemic malaria circulating; a number of imported cases of falciparum malaria have been reported in patients following return from international travel to a malaria endemic area. Therefore, it is important for health care professionals including pediatricians to be aware of the falciparum malaria and its clinical courses. Herein, we report a case of a 14-year-old girl with severe falciparum malaria that was complicated by blackwater fever.

In situ Hybridization for the Detection and Localization of the Bitter Taste Receptor Tas2r108 in the Murine Submandibular Gland

Mammals have 3 pairs of major salivary glands i.e., the parotid, submandibular, and sublingual glands. Saliva secretion of these glands is modulated by taste perception. Salivary glands are composed mainly of acinar and ductal cells. Primary saliva is secreted by acinar cells and modified during ductal flow. Recently, of the murine 35 bitter taste receptors, Tas2r108 was expressed at highest levels in the submandibular gland by qPCR. Further, Tas2r108-transfected cells respond to a range of bitter compounds, such as denatonium, quinine, colchicine, diphenidol, caffeine and dapson. The objective of the present study was to characterize the expression of Tas2r108 mRNA in acinar and/or ductal cells of the submandibular gland using in situ hybridization (ISH). Male 42-60 days old DBA2 mice were used in the study. Messenger RNAs were extracted from the submandibular gland for generating digoxigenin (DIG) labeled-cRNA probes. These probes were transcribed in anti-sense and sense orientation using T7 RNA polymerase. Dot blot hybridization was performed using DIG labeled-cRNA probes, in order to estimate integrity and optimal diluting concentration of these probes. Subsequently, ISH was performed on murine submandibular gland to detect Tas2r108 mRNA. Dot blot hybridization data demonstrated that Tas2r108 DIG labeled-cRNA anti-sense probes specifically detected Tas2r108 cDNA. ISH results showed that the anti-sense probes labeled acinar and ductal cells in the submandibular gland, whereas no staining was visible in sense controls. Interestingly, the Tas2r108 expression levels were higher in acinar than ductal cells. These results suggested that Tas2r108 might be more associated with primary saliva secretion than with ductal modification of saliva composition.

The Use of Orphan Drugs for Infectious Disease: Current Status and Unmet Needs / 대한내과학회지

BACKGROUND/AIMS: The aim of this study was to investigate the inconveniences and potential improvements in the use of orphan drugs for the treatment of infectious diseases, as determined by a survey of medical professionals. METHODS: An email was sent twice to the members of the Korean Society for Chemotherapy, and an online survey was conducted. The data collected were analyzed in terms of the frequency of drug use and associated difficulties as well as the scope for improvement. RESULTS: A total of 77 medical professionals participated in this survey. Rabies vaccine (n = 52), rabies immunoglobulin (n = 47), and foscarnet injection (n = 43) were supplied mainly through the Korea Orphan Drug Center (KODC), while artesunate (n = 29), quinine sulfate capsule (n = 24), quinine dihydrochloride injection (n = 23), and quinidine gluconate injection (n = 21) were supplied mainly through the National Medical Center (NMC). Difficulties in obtaining orphan drugs through the KODC were related to the KODC drug retrieval system (n = 67, 95.7% of respondents), lack of supplies on holidays (n = 66, 94.3%), complicated application procedures and documents (n = 61, 87.1%), and shipping inconveniences (n = 61, 87.1%). With regard to the use of orphan drugs supplied through the NMC, 52 participants (98.1%) responded that a staff visit should be mandatory for obtaining the drugs. CONCLUSIONS: Antivirals and antimalarial drugs are major orphan drugs used for the treatment of rare infections. It is necessary to establish a more efficient system to ensure a stable supply of orphan drugs, including on holidays, to enhance the smart drug searching system, and to simplify related administrative procedures.

The Bitter Taste Receptor Agonist Quinine Reduces Calorie Intake and Increases the Postprandial Release of Cholecystokinin in Healthy Subjects

BACKGROUND/AIMS: Bitter taste receptors are expressed throughout the digestive tract. Data on animals have suggested these receptors are involved in the gut hormone release, but no data are available in humans. Our aim is to assess whether bitter agonists influence food intake and gut hormone release in healthy subjects. METHODS: Twenty healthy volunteers were enrolled in a double-blind cross-over study. On 2 different days, each subject randomly received an acid-resistant capsule containing either placebo or 18 mg of hydrochloride (HCl) quinine. After 60 minutes, all subjects were allowed to eat an ad libitum meal until satiated. Plasma samples were obtained during the experiment in order to evaluate cholecystokinin (CCK) and ghrelin levels. Each subject was screened to determine phenylthiocarbamide (PTC) tasting status. RESULTS: Calorie intake was significantly lower when subjects received HCl quinine than placebo (514 +/- 248 vs 596 +/- 286 kcal; P = 0.007). Significantly higher CCK DeltaT90 vs T0 and DeltaT90 vs T60 were found when subjects received HCl quinine than placebo (0.70 +/- 0.69 vs 0.10 +/- 0.86 ng/mL, P = 0.026; 0.92 +/- 0.75 vs 0.50 +/- 0.55 ng/mL, P = 0.033, respectively). PTC tasters ingested a significantly lower amount of calories when they received HCl quinine compared to placebo (526 +/- 275 vs 659 +/- 320 kcal; P = 0.005), whereas no significant differences were found for PTC non-tasters (499 +/- 227 vs 519 +/- 231 kcal; P = 0.525). CONCLUSIONS: This study showed that intra-duodenal release of a bitter compound is able to significantly affect calorie intake and CCK release after a standardized meal. Our results suggest that bitter taste receptor signaling may have a crucial role in the control of food intake.

Partial characterization of Plasmodium falciparum trophozoite proteome under treatment with quinine, mefloquine and the natural antiplasmodial diosgenone / Caracterización parcial del proteoma del trofozoíto de Plasmodium falciparum bajo tratamiento con quinina, mefloquina y el compuesto natural diosgenona

Introduction: Despite efforts to control malaria, around 10% of the world population is at risk of acquiring this disease. Plasmodium falciparum accounts for the majority of severe cases and deaths. Malaria control programs have failed due to the therapeutic failure of first-line antimalarials and to parasite resistance. Thus, new and better therapeutic alternatives are required. Proteomic analysis allows determination of protein expression levels under drug pressure, leading to the identification of new therapeutic drug targets and their mechanisms of action. Objective: The aim of this study was to analyze qualitatively the expression of P.falciparum trophozoite proteins (strain ITG2), after exposure to antimalarial drugs, through a proteomic approach. Materials and methods: In vitro cultured synchronized parasites were treated with quinine, mefloquine and the natural antiplasmodial diosgenone. Protein extracts were prepared and analyzed by two-dimensional electrophoresis. The differentially expressed proteins were selected and identified by MALDI-TOF mass spectrometry. Results: The following proteins were identified among those differentially expressed in the parasite in the presence of the drugs tested: enolase (PF10_0155), calcium-binding protein (PF11_0098), chaperonin (PFL0740c), the host cell invasion protein (PF10_0268) and proteins related to redox processes (MAL8P1.17). These findings are consistent with results of previous studies where the parasite was submitted to pressure with other antimalarial drugs. Conclusion: The observed changes in the P. falciparum trophozoite protein profile induced by antimalarial drugs involved proteins mainly related to the general stress response.

Introducción. A pesar de los esfuerzos para controlar la malaria, esta sigue siendo un problema de salud pública. Plasmodium falciparum es responsable de la mayoría de los casos graves y de las muertes. Los programas de control de la malaria han sido cuestionados debido al fracaso del tratamiento y a la resistencia del parásito a los antipalúdicos de primera línea, por lo que se requieren nuevas y mejores alternativas. El análisis proteómico permite identificar y determinar los niveles de expresión de las proteínas bajo la presión de los medicamentos, lo que posibilita la identificación de nuevos blancos terapéuticos y mecanismos de acción. Objetivo. Analizar cualitativamente la expresión diferencial de proteínas del citosol del trofozoíto de P. falciparum bajo tratamiento con quinina, mefloquina y el compuesto natural diosgenona mediante una aproximación proteómica. Materiales y métodos. Se trataron trofozoítos sincronizados y cultivados in vitro de P. falciparum (cepa ITG2) con quinina, mefloquina y el compuesto natural diosgenona. Los extractos proteicos se prepararon y analizaron por electroforesis bidimensional. Las proteínas con aparente expresión diferencial se seleccionaron e identificaron mediante espectrometría de masas MALDI-TOF. Resultados. Se encontraron las siguientes proteínas diferencialmente expresadas en el trofozoíto: la enolasa (PF10_0155), la proteína de unión a calcio (PF11_0098), la chaperonina (PFL0740c), la proteína de invasión a la célula del huésped (PF10_0268) y la proteína relacionada con procesos de reducción y oxidación (redox) (MAL8P1.17). Estos hallazgos son congruentes con resultados previos de estudios en los que el parásito fue presionado con otros medicamentos antipalúdicos. Conclusión. Los cambios observados en el perfil de proteínas del trofozoíto de P. falciparum tratado con antipalúdicos involucraron preferencialmente proteínas relacionadas con la respuesta al estrés general.

Effects of pyrroloquinoline quinine on oxidative stress-induced apoptosis of Schwann cells and its mechanism / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the effects of Pyrroloquinoline quinine (PQQ) on hydrogen peroxide-induced apoptosis of Schwann cells (SCs) and its mechanism.</p><p><b>METHODS</b>SCs were isolated and cultured in vitro, and identified by S-100 immunofluorescence staining. The cultured SCs were divided into control group, hydrogen peroxide-treated group, hydrogen peroxide and PQQ treated groups. The intracellular superoxide dismutase (SOD) and malondialdehyde (MDA) content was detected; the apoptotic rate of SCs induced by hydrogen peroxide was determined by flow cytometry assay. The Hoechst33342 staining was used to detect the nuclear fragmentation and apoptotic nuclear condensation of SCs; the Rhodamine123 staining was used to detect the changes of mitochondrial membrane potential in SCs, the Western blot analysis was used to detect the expression of Bcl-2 in hydrogen peroxide induced SCs.</p><p><b>RESULTS</b>The SOD activity was significantly decreased and MDA level was increased in H2O2 induced SCs (P < 0.05), after addition of PQQ, the SOD content increased and MDA content decreased (P < 0.05). Flow cytometry results showed that the early apoptotic rate was 58.8% in H2O2 induced SCs, which has significant difference compared with the control group (P < 0.05), after addition of 10, 50, 100 nmol/L PQQ, the apoptotic rates were reduced to 33.7%, 18.7%, 3.9% respectively, showing significantly different with injured group (P < 0.05). Hoechst 33342 staining showed that H2O2 induced SCs had typical morphological characteristics, such as uptake of nuclear chromatin, nuclear shrinkage, nuclear fragmentation phenomenon. The proportion of apoptotic cells after PQQ treatment reduced. Rhodamine staining results showed that the H2O2 induced mitochondrial membrane potential reduction in SCs, which was reversed by addition of PQQ. Western blot analysis showed that the expression of Bcl-2 was decreased in H2O2 induced SCs, while it increased significantly after addition of PQQ (P < 0.05).</p><p><b>CONCLUSION</b>PQQ has a protective effect on oxidative stress-induced apoptosis of SCs.</p>

Differences in Taste Thresholds According to Sex and Age Groups in Korean / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The aim of the study was to compare the gustatory function between age-matched men and women in Korean subjects. SUBJECTS AND METHOD: Healthy non-smoking volunteers without smell and taste disorders were investigated. Thirty-nine men and women of the same age group were evaluated for gustatory function. Whole mouth taste test was performed with successive solutions of sucrose, sodium chloride, citric acid, and quinine hydrochloride. The electrical taste thresholds were measured using an electrogustometer for four different sites in the oral cavity, i.e., both sides of anterior and posterior tongue. RESULTS: Female subjects had lower mean values of detection and recognition thresholds for all of the four tastes than male subjects, although these results did not reach statistical significance except for the detection threshold for salt and the recognition threshold for quinine. In electrogustometry, thresholds in the posterior tongue of glossopharyngeal nerve area were significantly higher for men than women. CONCLUSION: Men had higher taste threshold than women of the same age category. For additional information on the effects of gender and aging on taste thresholds, further studies including a large number of well-controlled subjects are essential.

First Report of Neutrophil Involvement of Exflagellated Plasmodium vivax Microgametes

No abstract available.

Efficacy of Phenytoin for Nocturnal Muscle Cramps: A Preliminary Study

BACKGROUND: Nocturnal muscle cramps are sudden, involuntary, painful muscle contractions that occur in the night and are accompanied by hardening of the muscles. Many symptomatic treatments have been introduced for nocturnal muscle cramps, such as quinine, magnesium, and phenytoin. However, the efficacy and safety of these drugs have not been adequately evaluated. To demonstrate the efficacy and safety of phenytoin treatment for nocturnal muscle cramps, we conducted a retrospective study of 16 patients with nocturnal muscle cramps. METHODS: We reviewed 16 patients (6 men, 10 women) who suffered frequent nocturnal muscle cramps and were treated with phenytoin. The patients' clinical information (age, sex, disease duration, and locations of cramps), treatment dosage, and frequency of cramps were obtained by reviewing their medical records. RESULTS: The patients were aged 63.1+/-14.7 years (mean+/-SD; age range, 30-80 years; median age, 68 years). Twelve and four patients received phenytoin doses of 100 and 200 mg/day, respectively. The median duration of medication was 51 days (range, 14-378 days). Phenytoin treatment was effective in all patients; 13 patients (81.3%) experienced a total remission of their symptoms, and a significant reduction (66.7-85.7%) in the frequency of cramps was found in the remaining 3 patients. No adverse effects were reported by any of the patients. CONCLUSIONS: While this retrospective study was conducted with only a small number of patients, the clinical results suggest that phenytoin is a safe and helpful therapy for the treatment of nocturnal muscle cramps.

Cuantificación de quinina en extractos de Cinchona pubescens y evaluación de la actividad antiplasmodial y citotóxica / Quantification of quinine in extracts from stems Cinchona pubescens and evaluation of antiplasmodial and cytotoxic activity

Plants belonging to the genus Cinchona L. (Rubiaceae), whose active ingredient is quinine, was used for centuries to treat malaria. Plants of this genus are a potential source of new structural templates in the search for new antimalarial candidates. This study aimed to the identification, quantification of quinine and other metabolites present in extracts of different polarity of the stems of Cinchona pubescens Vahl. , oxoquinovic acid isolation, antiplasmodial activity, and measuring its cytotoxic effect. The results show a high activity to antiplasmodial alkaloids extract (IC50 = 2.20 +/- 0.0325 ug/mL), cytotoxicity (CC50 = 80.2 +/- 12.2 ug/mL), and a quinine content of 21.3+/-0.0247 ppm. The compound known as acid antiplasmodial activity oxoquinovic presented in IC50 = 11.3 +/- 0.741 ug/mL, and cytotoxicity CC50 = 72.4 +/- 3.85 ug/mL. These results motivate phytochemical studies in the search for active structural analogues quinine and quinolinic core as a source of new antimalarial agents.

Las plantas pertenecientes al género Cinchona L. (familia Rubiaceae), cuyo principio activo es la quinina, fueron utilizadas durante siglos para tratar la malaria. Este género es una fuente potencial de nuevas plantillas estructurales en la búsqueda de nuevos candidatos antimaláricos. El presente trabajo tuvo como objetivo la identificación y, cuantificación de la quinina y de otros metabolitos presentes en los extractos de diferente polaridad, de los tallos de Cinchona pubescens Vahl. , el aislamiento del ácido oxoquinóvico, la actividad antiplasmodial y, además, la medición de su efecto citotóxico. Los resultados muestran una alta actividad antiplasmodial para el extracto de los alcaloides (IC50 = 2,20 +/- 0,0325 ug/mL), una baja citotoxicidad (CC50 = 80,2 +/- 12,2 ug/mL), y un alto contenido de quinina el cual fue 21,3+/-0,0247 ppm. El compuesto ácido oxoquinóvico presentó una actividad antiplasmodial de IC50 = 11,3 +/- 0.741 ug/mL, y una citotoxicidad de CC50 = 72,4 +/- 3,85 ug/mL. Estos resultados motivan los estudios fitoquímicos en la búsqueda de principios activos y análogos estructurales en diferentes especies de Cinchonas como una fuente de nuevos agentes antimaláricos.

Possible artemisinin-based combination therapy-resistant malaria in Nigeria: a report of three cases

Artemisinin-based combination therapy-resistant malaria is rare in Sub-Saharan Africa. The World Health Organization identifies monitoring and surveillance using day-3 parasitaemia post-treatment as the standard test for identifying suspected artemisinin resistance. We report three cases of early treatment failure due to possible artemisinin-based combination therapy-resistant Plasmodium falciparum malaria. All cases showed adequate clinical and parasitological responses to quinine. This study reveals a need to re-evaluate the quality and efficacy of artemisinin-based combination therapy agents in Nigeria and Sub-Saharan Africa.

Metabolites and metabolic pathways of mesaconitine in rat liver microsomal investigated by using UPLC-MS/MS method in vitro / 药学学报

Mesaconitine was incubated with rat liver microsomes in vitro. The metabolites of mesaconitine in rat liver microsomes were identified by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method with high resolution power. A typical reaction mixture of 100 mol L-1 Tris-HCI buffer (pH 7.4) containing 0.5 gL-1 microsomal protein and 50 micro molL-1 mesaconitine was prepared. The above reaction mixture was divided into six groups, and the volume of each group was 200 micro L. The incubation mixture was pre-incubated at 37 degrees C for 2 min and the reactions were initiated by adding NADPH generating system. After 90 min incubation at 37 degrees C, 200 micro L of acetonitrile was added to each group to stop the reaction. The metabolites of mesaconitine were investigated by UPLC-MS/MS method. Mesaconitine and 6 metabolites M1-M6 were found in the incubation system. The structures were characterized according to the data from MS/MS spectra and literatures. The metabolic reactions of mesaconitine in rat liver microsomes included the demethylation, deacetylation, dehydrogenation and hydroxylation. The major metabolic pathways of mesaconitine in rat liver microsomes were determined by UPLC-MS/MS on multiple reaction monitoring (MRM) mode combined with specific inhibitors of cytochrome P450 (CYP) isoforms, including alpha-naphthoflavone (CYP1A2), quinine (CYP2D), diethyldithiocarbamate (CYP2E1), ketoconazole (CYP3A) and sulfaphenazole (CYP2C), separately. Mesaconitine was mainly metabolized by CYP3A. CYP2C and CYP2D were also more important CYP isoforms for the metabolism reactions of mesaconitine, but CYP1A2 and CYP2E1 haven't any contribution to MA metabolism in rat liver microsomes.

Congenital plasmodium falciparum in a neonate in Kuwait

We report the case of a newborn infant who was diagnosed with congenital malaria. This baby was admitted for evaluation of fever which began four days prior to admission. The newborn was pale and had spleenomegaly and normal neonatal reflexes. Laboratory tests, including a peripheral blood smear, revealed Plasmodium falciparum in the red cells. His mother had suffered from malaria eight months back in India for which she took quinine for seven days. The newborn was successfully treated with quinine. He was discharged from the hospital in a good condition with negative blood smears

Chemotherapy and drug resistance status of malaria parasite in northeast India

India reports the highest number of malaria cases in Southeast Asia, of which Plasmodium falciparum contribute more than half of the cases every year. North eastern states of India contribute only 3.96% of country's population but account for >10% of total reported malaria cases, 11% of Plasmodium falciparum cases and 20% of malaria related deaths annually. In India, chloroquine resistance was reported for the first time from northeast region and since then chloroquine treatment failure is being reported from many parts of the region. Increased chloroquine treatment failure has led to change of the drug policy to artemisinin combination therapy as first line of malaria treatment in the region. However, replacing chloroquine to artemisinin combination therapy has not shown significant difference in the overall malaria incidence in the region. The present review addresses the current malaria situation of northeastern region of India in the light of antimalarials drug resistance.