Leeaoside,a new megastigmane diglycoside from the leaves of <Emphasis Type="Italic">Leea thorelii</Emphasis> Gagnep

A new megastigmane diglycoside, leeaoside, was isolated along with four known compounds; benzyl O-α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside, quercetin 3-O-α-l-rhamnopyranoside, myricetin 3-O-α-l-rhamnopyranoside and citroside A from the leaves of Leea thorelli. The structure determinations were based on physical data and spectroscopic evidence.     

Cardiovascular effects of 14-deoxy-11,12-didehydroandrographolide and Andrographis paniculata extracts

Andrographis paniculata has been widely used as a traditional medicine for the treatment of common cold, diarrhea and hypertension. The three major active diterpenoids are andrographolide (AP1), 14-deoxy-11,12-didehydroandrographolide (AP3) and neoandrographolide (AP4). It has been reported that AP3 has hypotensive and vasorelaxation effects. However, there is only limited information on the cardiovascular effects of the other diterpenoids and crude extracts containing different levels of AP3. Therefore, the present study investigated the effects of these diterpenoids, AP1, AP3, and AP4, isolated from A. paniculata, and different aqueous plant extracts on blood pressure, vascular and chronotropic responses by using conscious rats and their isolated aortas and right atria as the test models. Among the three major diterpenoids, AP3 was the most potent compound for inducing vasorelaxation and decreasing heart rate. In addition, Extract B (high level of AP3) had greater hypotensive effect in conscious rats than Extract A (low level of AP3). Verapamil, a Ca2+ channel blocker, also had a hypotensive effect less than that of Extract C containing a high level of AP3. At the doses and durations of Extract A and B which produced hypotension, the responses of the Extract A-treated aorta to norepinephrine, and the vascular muscarinic responses to acetylcholine of both extracts were decreased. However, repeated doses of both extracts did not alter cardiac beta-adrenoceptor and muscarinic responses of extract-treated rats to NE and ACh, respectively. The results of this study suggest that vascular smooth muscle is the major site of these hypotensive effects of both AP3 and A. paniculata extracts. Furthermore, the consumption of A. paniculata products containing high levels of AP3 may be responsible for causing hypotension in some patients taking this herbal drug.     

Additional Drug Resistance of Multidrug-Resistant Tuberculosis in Patients in 9 Countries

Data from a large multicenter observational study of patients with multidrug-resistant tuberculosis (MDR TB) were analyzed to simulate the possible use of 2 new approaches to treatment of MDR TB: a short (9-month) regimen and a bedaquiline-containing regimen. Of 1,254 patients, 952 (75.9%) had no resistance to fluoroquinolones and second-line injectable drugs and thus would qualify as candidates for the 9-month regimen; 302 (24.1%) patients with resistance to a fluoroquinolone or second-line injectable drug would qualify as candidates for a bedaquiline-containing regimen in accordance with published guidelines. Among candidates for the 9-month regimen, standardized drug-susceptibility tests demonstrated susceptibility to a median of 5 (interquartile range 5–6) drugs. Among candidates for bedaquiline, drug-susceptibility tests demonstrated susceptibility to a median of 3 (interquartile range 2–4) drugs; 26% retained susceptibility to <2 drugs. These data may assist national TB programs in planning to implement new drugs and drug regimens.     

Anti-metastatic effects of aqueous extract of Helixanthera parasitica

Metastasis, the spread of cancer in body, is a major cause of death. We have screened anti-metastatic activity of aqueous and dichloromethane extracts of several not previously studied Thai herbs, using an in vitro invasion test. This involves the in vitro invasion of HCC-S102, a hepatocellular carcinoma cell line derived from a Thai patient, through a reconstituted-basement membrane (Matrigel). The aqueous extract of a plant (Helixanthera parasitica) revealed a significant inhibitory effect on the cancer cell invasion, and showed antioxidant activity. The aqueous extract was partially purified by silica gel column chromatography, and the highest anti-metastatic activity fraction showed 83% inhibition of invasion with low cytotoxic effect. However, anti-metastatic activity was not associated with the antioxidant activity of the aqueous extract.     

Pharmacodynamic Interaction of Doxycycline and Artemisinin in Plasmodium falciparum

Parallel in vitro tests, assessing the inhibition of schizont maturation, were conducted with 31 fresh isolates of Plasmodium falciparum from Thailand, using artemisinin, doxycycline, and combinations of both. The activities of artemisinin and doxycycline are obviously not correlated. Both compounds showed consistent synergism at 50% effective concentration (EC(50)), EC(90), and EC(99) levels.     

Characterization of patients with disc displacement without reduction unresponsive to nonsurgical treatment: a preliminary study.

PURPOSE: Arthrocentesis and arthroscopic lysis and lavage have been described as effective treatment modalities for temporomandibular joint (TMJ) disc displacement without reduction (DDw/oR). More commonly, nonsurgical intervention is offered as the desired first-line treatment; however, a certain group of DDw/oR patients receiving nonsurgical treatment may remain unresponsive, thereby prolonging suffering and treatment dissatisfaction. The purpose of this study is to characterize these nonresponders by evaluating the characteristic pretreatment findings peculiar to this group. PATIENTS AND METHODS: This retrospective study was based on the review of pretreatment clinical and magnetic resonance imaging (MRI) findings of 52 DDw/oR patients who were treated with stabilization appliance, jaw-stretching exercise, and nonsteroidal anti-inflammatory medication. On the last treatment visit, each patient was classified as either a responder (R) or nonresponder (NR) based on the satisfaction or dissatisfaction with the treatment received, respectively. Pretreatment data were then examined and analyzed by logistic regression to identify which clinical and MRI findings were specifically related to the NR group. RESULTS: Logistic regressions indicated that NR had significantly higher odds ratio for pretreatment pain-free mouth opening of less than 30 mm (odds ratio [OR] = 7.385), "stuck" disc (OR = 4.521), and unchanged disc shape during mouth opening (OR = 4.050). Multiple logistic regression analyses revealed that these factors combined gave the highest likelihood ratio of 15.90 ( P = .001), indicating a strong possibility that these factors are associated with the NR group. CONCLUSIONS: Nonresponders can be characterized by their pretreatment pain-free mouth opening (<30 mm) in combination with MRI confirmation of "stuck" disc and unchanged disc shapes during mouth opening.     

Genetic differences of E gene of a Thai strain of Japanese encephalitis virus that determine small plaque size phenotype but not neurovirulence in suckling mice

Two small plaque variants of Japanese encephalitis virus (JEV), S4P9 and S9P10, were recovered from the wild type of JEV strain KE-093 using plaque purification in combination with the temperature-shift induction technique. Growth patterns of the S4P9 and S9P10 in BHK-21 cells as well as neurovirulence in suckling mice were similar to that of KE-093. An amino acid substitution, lysine for glutamic acid, was present in envelope protein at residue E-83 in the small plaque variants. This study shows that small plaque phenotype is not always associated with attenuation in vivo.     

Larval morphology of Chrysomya nigripes (Diptera: Calliphoridae), a fly species of forensic importance

The morphology of all instars of Chrysomya nigripes Aubertin, a blow fly species of forensic importance, is presented with the aid of both light microscopy and scanning electron microscopy (SEM). Morphological features of the cephalopharyngeal skeleton, anterior spiracle, posterior spiracle, and dorsal spines between the prothorax and mesothorax are highlighted. No consistent features were found, even using SEM, for distinguishing the first instar of C. nigripes from that of Chrysomya megacephala (F.) or Chrysomya rufifacies (Macquart), two other commonly associated blow fly species in corpses in Thailand. Several features observed in second and third instars proved to be valuable characteristics for separating these species.     

Friedolanostanes and lanostanes from the leaves of Garcinia hombroniana

Five new triterpenes, one 17,14-friedolanostane (garcihombronane F, 1), three 17,13-friedolanostanes (garcihombronanes G-I, 2-4), and one lanostane (garcihombronane J, 5), were isolated from the leaves of Garcinia hombroniana together with nine known compounds including five triterpenes, two ionone-derived glycosides, and two flavonoid glucosides. Their structures were identified by analysis of spectroscopic data and comparison of the NMR data with those previously reported.