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Background: The efficacy of Centella asiatica for incision and burn wounds are not fully understood. Here, we report the wound healing activities of sequential hexane, ethyl acetate, methanol, and water extracts of Centella asiatica in incision and partial-thickness burn wound models in rats., Methods: Male Sprague-Dawley rats weighing 250-300 g were randomly divided into incision and burn wound groups. Each group was stratified into seven subgroups: (1) untreated; (2) NSS-; (3) Tween 20®- (vehicle control); (4) hexane extract-; (5) ethyl acetate extract-; (6) methanol extract-; and (7) aqueous extract-treated groups. The test substances were applied topically once daily. The tensile strength of the incision wound was measured on the seventh day after wound infliction. The general appearance and degree of wound healing of the burn wound were assessed on Days 3, 7, 10 and 14 after burn injury and prior to histopathological evaluation., Results: On the seventh day after wound infliction, the tensile strength of incision wound in all extract-treated groups was significantly higher than that of the vehicle control (Tween 20®), but comparable to the NSS-treated group. The degrees of healing in the burn wound with the four extracts were significantly higher than that of the control on Days 3, 10 and 14. Histopathological findings on Day 14 after burn injury revealed prominent fibrinoid necrosis and incomplete epithelialization in the control and untreated groups, whereas fully developed epithelialization and keratinization were observed in all extract-treated groups. Analysis by thin layer chromatography demonstrated that the phyto-constituents β-sitosterol, asiatic acid, and asiaticoside and madecassocide were present in the hexane, ethyl acetate and methanol extracts, respectively., Conclusions: All extracts of Centella asiatica facilitate the wound healing process in both incision and burn wounds. Asiatic acid in the ethyl acetate extract seemed to be the most active component for healing the wound.

Objective: To assess safety and tolerability of enfuvirtide, an antiretroviral, in Thai patients with advanced HIV-1 disease who have received antiretroviral treatment and failed on regimens that contain at least one of each antiretroviral (ARV) classes (PIs, NRTIs, and NNRTIs), or who have intolerance to previous antiretroviral regimens., Material and Method: An open-label non-comparative study of enfuvirtide used in salvage regimens along with the backbone antiretroviral therapy of choice in Thai HIV-1 experienced cases that have been treated with at least one of each available ARV classes., Results: Twenty-three patients were recruited from five participating centers. Seventeen patients (74%) completed 96 weeks of the treatment. Six patients prematurely withdrew from the present study in which three expired from HIV related complications, two withdrew consents, and one from adverse event. The most common adverse event is injection site reactions, which occurred in 22 patients. The manifestations and intensity varied from rash, erythema, edema, pain, induration, and bleeding at the injection sites, to inflammatory nodules. Most of the patients tolerated the treatment well. Enfuvirtide administered along with other antiretroviral combination provided a good control of the disease., Conclusion: Enfuvirtide was well tolerated by Thai patients who participated in the present study. The adverse events did not compromise the patient compliance.

The constitutive expression of the rice Osmyb4 gene in Arabidopsis plants gives rise to enhanced abiotic and biotic stress tolerance, probably by activating several stress-inducible pathways. However, the effect of Osmyb4 on stress tolerance likely depends on the genetic background of the transformed species. In this study, we explored the potential of Osmyb4 to enhance the cold and freezing tolerance of Osteospermum ecklonis, an ornamental and perennial plant native to South Africa, because of an increasing interest in growing this species in Europe where winter temperatures are low. Transgenic O. ecklonis plants were obtained through transformation with the Osmyb4 rice gene under the control of the CaMV35S promoter. We examined the phenotypic adaptation of transgenic plants to cold and freezing stress. We also analysed the ability of wild-type and transgenic Osteospermum to accumulate several solutes, such as proline, amino acids and sugars. Using nuclear magnetic resonance, we outlined the metabolic profile of this species under normal growth conditions and under stress for the first time. Indeed, we found that overexpression of Osmyb4 improved the cold and freezing tolerance and produced changes in metabolite accumulation, especially of sugars and proline. Based on our data, it could be of agronomic and economic interest to use this gene to produce Osteospermum plants capable of growing in open field, even during the winter season in climatic zone Z9., (2010 Elsevier Masson SAS. All rights reserved.)

Constitutive expression of the rice cold-inducible Osmyb4 gene in transgenic Arabidopsis (Arabidopsis thaliana) plants improves adaptive responses to cold and drought stress, most likely due to the constitutive activation of several stress-inducible pathways and to the accumulation of several compatible solutes (e.g., glucose, fructose, sucrose, proline, glycine betaine and some aromatic compounds). Although the Osmyb4 gene seems able to activate stress responsive pathways in different species, we previously reported that its specific effect on stress tolerance depends on the transformed species. In the present work, we report the effects of the Osmyb4 expression for improving the stress response in apple (Malus pumila Mill.) plants. Namely, we found that the ectopic expression of the Myb4 transcription factor improved physiological and biochemical adaptation to cold and drought stress and modified metabolite accumulation. Based on these results it may be of interest to use Osmyb4 as a tool for improving the productivity of woody perennials under environmental stress conditions.

Mybleu is a natural incomplete transcription factor of rice (Oryza sativa), consisting of a partial Myb repeat followed by a short leucine zipper. We previously showed its localization to the apical region of rice roots and coleoptiles. Specifically, in coleoptiles, Mybleu is expressed under both aerobic and anaerobic conditions, whereas in roots, it is expressed only under aerobic conditions. Mybleu is able to dimerize with canonical leucine zippers and to activate transcription selectively. To investigate Mybleu function in vivo, we transformed Arabidopsis thaliana and evaluated several morphological, physiological and biochemical parameters. In agreement with a hypothesized role of Mybleu in cell elongation in the differentiation zone, we found that the constitutive expression of this transcription factor in Arabidopsis induced elongation in the primary roots and in the internodal region of the floral stem; we also observed a modification of the root apex morphology in transformed lines. Based on the high expression of Mybleu in anaerobic rice coleoptiles, we studied the role of this transcription factor in transgenic plants grown under low-oxygen conditions. We found that overexpression of this transcription factor increased tolerance to oxygen deficit. In transgenic plants, this effect may depend both on the maintenance of a higher metabolism during stress and on the higher expression levels of certain genes involved in the anaerobic response.

Stavudine is a nucleoside analogue used for the treatment of HIV-1 infection, as part of highly active antiretroviral treatment. In developing countries, stavudine is used widely, owing to low cost and inclusion in generic fixed-dose combinations. In developed countries, stavudine is now rarely used, although it is highly effective. This is because newer drugs show lower rates of mitochondrial toxicities, such as lipoatrophy, peripheral neuropathy and lactic acidosis. In the development of stavudine, there was evidence that a dosage of 20-30 mg b.i.d. was effective, but the 40-mg b.i.d. dose gained regulatory approval. This review analyses the clinical trials conducted before and after the regulatory approval of stavudine, and shows that the dose of 30 mg b.i.d. has equivalent antiviral efficacy (given the caveats of meta-analysis), with some evidence of lower rates of peripheral neuropathy and lipoatrophy. With limited resources for HIV-1 treatment in developing countries, and only 25% of eligible patients receiving highly active antiretroviral treatment, low-cost treatment options such as stavudine still need to be pursued, if safety can be improved by dose optimisation.

Spinal cord injury without radiologic abnormalities is a rare condition that occurs more frequently in children and contributes to a high rate of morbidity among these patients. We report the case of a five-month-old infant, victim of automobile accident, who was brought to our service with a sensitive level in T2 and bilateral crural paraplegia. Radiographic exams and computed tomography of spine did not evidence of bone or ligaments injuries. Magnetic resonance image showed complete spinal cord transection and spine avulsion in the segment between T3 and T7. We discuss this pathology according to its epidemiology, pathophysiology, diagnosis, treatment and prognostic aspects.

The expression of the gene Osmyb4, detected at low level in rice (Oryza sativa) coleoptiles grown for 3 days at 29 degrees C, is strongly induced by treatments at 4 degrees C. At sublethal temperatures of 10 and 15 degrees C, its expression in rice seedlings is already evident, but this effect cannot be vicariated by other stresses or ABA treatment. We demonstrate by transient expression that Myb4 transactivates the PAL2, ScD9 SAD and COR15a cold-inducible promoters. The Osmyb4 function in vivo is demonstrated overexpressing its cDNA in Arabidopsis thaliana plants (ecotype Wassilewskija) under the control of the constitutive CaMV 35S promoter. Myb4 overexpressing plants show a significant increased cold and freezing tolerance, measured as membrane or Photosystem II (PSII) stability and as whole plant tolerance. Finally, in Osmyb4 transgenic plants, the expression of genes participating in different cold-induced pathways is affected, suggesting that Myb4 represents a master switch in cold tolerance.

INH preventive therapy (IPT) has been shown in several randomized controlled trials to reduce the risk of developing active TB in tuberculin skin test (TST) or purified protein derivative (PPD) positive HIV infected individuals. Detection of latent tuberculosis by TST and determination of factors associated with the PPD positivity in HIV-infected persons are important for the targeting of chemoprophylaxis. Six hundred asymptomatic and early symptomatic HIV-infected subjects attending the AIDS Clinic of the Chulalongkorn University Hospital, Bangkok, Thailand were enrolled in two randomized clinical trials of chemoprophylaxis against TB from December 1994 to December 1996. The availability of baseline characteristics, including TST reactivity, among these participants enabled a cross-sectional analysis of factors associated with PPD positivity. The results showed that 117 (19.5%) were PPD positive and 483 (80.5%) were PPD negative with ages 18-65 years (median 29 years). HIV exposure category was 46.2%, 34.5%, and 6.7% for heterosexual contact, commercial sex work, and homosexual and bisexual male contact respectively. The median CD4 cell count was 315/mm3 (range, 5-1,074/mm3). HIV exposure category and CD4 cell count were significantly associated with PPD status. Homosexual/bisexual contact had 3 times higher risk of PPD positivity than heterosexual contact (adjusted OR=2.9; 95% CI, 1.4-6.1) and risk of PPD positivity was higher among patients with CD4 cell counts of 200-500/ mm3 (adjusted OR=1.8; 95% CI, 1.0-3.1) and above 500/mm3 (adjusted OR=3.4; 95% CI, 1.7-6.7) when compared to patients with CD4 cell counts of less than 200/mm3. The HIV-infected persons in Bangkok with homosexual/bisexual contact are at higher risk for latent TB. Population-based tuberculin screening without accompanying HIV testing cannot be used to estimate the prevalence of actual latent TB in a population where HIV infection is widespread, such as in Thailand.

(31)P nuclear magnetic resonance spectroscopy was used to measure intracellular pH in living tissues. Oxygen deprivation caused fast cytoplasmic acidification from pH 7.4 to 7.0 in shoots of rice, Oryza sativa L. var arborio, a species highly resistant to anoxia. Acidification was complete after 10 minutes of anoxia. Alkalinization of both cytosplasm and vacuole followed thereafter. In the anoxia intolerant wheat shoots, Triticum aestivum L. var MEK, the same treatment caused a sharper cytoplasmic acidification, from pH 7.4 to 6.6, which occurred during a period of 2 hours. Cytoplasmic acidification continued with progress of anoxia and there was no vacuolar alkalinization comparable to the one observed in rice. In wheat oxyen, withdrawal also caused the reduction of both glucose-6-phosphate level and of metabolic rate. It also induced heavy losses of inorganic phosphate from tissues. Conversely, in rice, glucose-6-phosphate level and metabolic rate were increased and inorganic phosphate leakage from tissues was completely absent. These results are discussed in relation to the mechanisms of plant resistance to anoxia.