Determination of Antioxidant, Cytotoxicity, and Acetylcholinesterase Inhibitory Activities of Alkaloids Isolated from Sophora flavescens Ait. Grown in Dak Nong, Vietnam

Traditional/herbal medicine has gained increasing interests recently, especially in Asian countries such as Vietnam, due to its diverse therapeutic actions. In the treasure of Vietnamese medicinal plants, one of the potential herbs is the roots of Sophora flavescens Ait. (SF, "Kho sam" in Vietnamese). However, limited information has been reported on the Vietnamese SF compositions and their respective alkaloids' anti-acetylcholinesterase action. Thus, this study investigated the extractions, isolations, identifications, and in-vitro antioxidant, cytotoxicity, and acetylcholinesterase inhibitory activities, of the SF root extracts and their purified alkaloid compounds. To this end, four pure compounds were successfully isolated, purity-tested by HPLC, and structurally identified by spectroscopic techniques of FTIR, MS, and NMR. These compounds, confirmed to be oxysophocarpine, oxymatrine, matrine, and sophoridine, were then determined their therapeutic actions. The SF extracts and the compounds did not possess significant antioxidant activity using the DPPH and MDA assays, and cytotoxicity action using the MTT assay on the MDA-MB-231 breast cancer cell line. On the other hand, the SF total extract yielded a moderate acetylcholinesterase inhibition effect, with an IC50 of 0.1077 ± 0.0023 mg/mL. In summary, the SF extract demonstrated potential effects as an anti-acetylcholinesterase agent and could be further researched to become a pharmaceutical product for diseases related to acetylcholine deficiency, such as dementia.

FoxP1 marks medium spiny neurons from precursors to maturity and is required for their differentiation

Identifying the steps involved in striatal development is important both for understanding the striatum in health and disease, and for generating protocols to differentiate striatal neurons for regenerative medicine. The most prominent neuronal subtype in the adult striatum is the medium spiny projection neuron (MSN), which constitutes more than 85% of all striatal neurons and classically expresses DARPP-32. Through a microarray study of genes expressed in the whole ganglionic eminence (WGE: the developing striatum) in the mouse, we identified the gene encoding the transcription factor Forkhead box protein P1 (FoxP1) as the most highly up-regulated gene, thus providing unbiased evidence for the association of FoxP1 with MSN development. We also describe the expression of FoxP1 in the human fetal brain over equivalent gestational stages. FoxP1 expression persisted through into adulthood in the mouse brain, where it co-localised with all striatal DARPP-32 positive projection neurons and a small population of DARPP-32 negative cells. There was no co-localisation of FoxP1 with any interneuron markers. FoxP1 was detectable in primary fetal striatal cells following dissection, culture, and transplantation into the adult lesioned striatum, demonstrating its utility as an MSN marker for transplantation studies. Furthermore, DARPP-32 expression was absent from FoxP1 knock-out mouse WGE differentiated in vitro, suggesting that FoxP1 is important for the development of DARPP-32-positive MSNs. In summary, we show that FoxP1 labels MSN precursors prior to the expression of DARPP-32 during normal development, and in addition suggest that FoxP1 labels a sub-population of MSNs that are not co-labelled by DARPP-32. We demonstrate the utility of FoxP1 to label MSNs in vitro and following neural transplantation, and show that FoxP1 is required for DARPP-32 positive MSN differentiation in vitro.

Liver involvement associated with dengue infection in adults in Vietnam

Globally, the number of adults hospitalized with dengue has increased markedly in recent years. It has been suggested that hepatic dysfunction is more significant in this group than among children. We describe the spectrum and evolution of disease manifestations among 644 adults with dengue who were prospectively recruited on admission to a major infectious disease hospital in southern Vietnam and compare them with a group of patients with similar illnesses not caused by dengue. Transaminase levels increased in virtually all dengue patients and correlated with other markers of disease severity. However, peak enzyme values usually occurred later than other complications. Clinically severe liver involvement was infrequent and idiosyncratic, but usually resulted in severe bleeding. Chronic co-infection with hepatitis B was associated with modestly but significantly increased levels of alanine aminotransferase, but did not otherwise impact the clinical picture.

Management of multiple drug-resistant malaria in Viet Nam

Malaria is still the most common infectious cause of mortality and morbidity in Viet Nam as it is in many developing countries in the tropics. The presence of resistance to available antimalarials and compliance in the target population are factors that influence the choice of drugs and regimens. In order to develop an ideal treatment for malaria, we conducted several clinical trials in patients with the disease in different settings. The results of these trials suggest that a combination of single dose artemisinin (or its derivatives) and mefloquine is the most effective, safe and practical treatment for acute non-complicated malaria due to multidrug-resistant Plasmodium falciparum. Concerning severe and complicated malaria, parenteral or rectal multi-doses of artemisinin or analogues are recommended due to their rapid parasite clearance time and other possible anti-cytoadherence effects. With its rapid parasite clearance, very early treatment of uncomplicated cases with artemisinin (and derivatives), especially at a health post level may help to prevent the development of complications, consequently reducing the number of severe cases and the malaria mortality rate.

Comparison of artemisinin suppositories with intravenous artesunate and intravenous quinine in the treatment of cerebral malaria

Seventy-nine comatose cerebral malaria patients given standard supportive treatment were randomized to receive specific antimalarial chemotherapy of intravenous quinine, intravenous artesunate, or artemisinin suppositories. Artesunate and artemisinin reduced peripheral asexual parasitaemia significantly more rapidly than quinine (90% clearance time 16 h, 18.9 h and 34.5 h respectively), but did not significantly reduce the duration of coma or mortality. The rapid lowering of peripheral parasitaemia may not ameliorate complications already present. These results demonstrate that artemisinin suppositories are as effective as artesunate and quinine given intravenously, and have economic and practical advantages for the treatment of severe malaria in areas remote from major medical centres. However, large numbers of patients will need to be studied if differences in mortality between the 3 treatment groups are to be demonstrated.