Predictors of low CD4 count in resource-limited settings: based on an antiretroviral-naive heterosexual thai population

A barrier to the appropriate provision of antiretroviral therapy to treat immunosuppressed HIV-infected persons in resource-poor countries is identifying who requires treatment. The World Health Organization (WHO) has suggested using a clinical algorithm combined with a total lymphocyte count (TLC) < 1200 cells/mm as a surrogate for a CD4 count less than 200 cells/mm when it is not possible to measure the CD4 count. We evaluated various TLC levels, anemia, and body mass index and compared our data with the WHO criteria to develop a more sensitive algorithm to predict CD4 counts of < 200 cells/mm and < 350 cells/mm in 839 men and women from Thailand infected with HIV-1 subtype E (CRF01_AE). The December 2003 WHO guidelines had a sensitivity of 34.1% in men and 31.8% in women to detect persons with a CD4 count < 200 cells/mm in this HIV-infected population from Thailand. The use of a TLC < 1500 cells/mm or TLC < 2000 cells/mm combined with anemia or WHO stage II infection doubled the sensitivity to detect persons with a CD4 count < 200 (63.0% in men, 68.2% in women) with less than a 6% decrease in specificity.     

Fragment antigen-binding (Fab) antibody-based lateral flow immunoassay for rapid and sensitive detection of potent phytoestrogen,deoxymiroestrol

Pueraria candollei is an ingredient of Thai herbal medicine, dietary supplements, and cosmetics. The in vitro and in vivo studies of this plant supported anti-osteoporotic activity and used for hormone replacement therapy. Deoxymiroestrol shows the most potent phytoconstituent in tuberous root of P. candollei with estrogenic activity. The quality controls are important for good agricultural practice (GAP) and good manufacturing practice (GMP) of plant-derived raw materials. The rapid detection of lateral flow immunoassay (LFIA) using colloidal gold is simply method, easy visualize detection and produce less waste than conventional chromatographic detection. In this study, LFIA for qualitative detection of deoxymiroestrol using antigen-binding fragment antibody (Fab) was developed. The result showed that the developed LFIA displays specific detection of deoxymiroestrol. Cross reactivity of this method was analyzed with miroestrol, isomiroestrol and methylisomiroestrol which showed 39.97%, 7.71% and 5.72%, respectively. After optimal condition, limit of detection (LOD) for deoxymiroestrol is 250 ng/ml. Plant samples were applied to strip test compare with indirect competitive ELISA using polyclonal antibody to confirm the application of LFIA. The results of LFIA method were comparable with those from ELISA. This developed lateral flow immunoassay can apply to detect deoxymiroestrol for the rapid testing. The developed method can use for quality control in plant samples as deoxymiroestrol is biomarker compound in P. candollei.

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Cytotoxicity and QSAR study of (thio)ureas derived from phenylalkylamines and pyridylalkylamines

Simplified 1,3-disubstituted urea derivatives (11–24) of phenylethylamines, homoveratylamines, 2-pyridylethylamines, 2-picolylamines as well as xylylenediamines were synthesized and investigated for their cytotoxic activities. The results revealed that most analogs displayed cytotoxicity against HepG2 and MOLT-3 cell lines. The bis-thiourea derivatives 23 and 24 exhibited higher inhibitory potency against HepG2 cell than the reference drug, etoposide. 1,1′-(1,3-phenylenebis(methylene))bis(3-(4-chlorophenyl)thiourea) 24 was shown to be the most potent cytotoxic compound against MOLT-3 cell line with an IC₅₀ value of 1.62 μM. QSAR studies suggested that compounds with high ionization potential displayed high cytotoxicity against HuCCA-1 cell line. Furthermore, derivatives with dimethoxyphenyl group had high radial distribution function with a correspondingly high cytotoxicity against A549 cell line. Moreover, analogs 23 and 24 had low values of E _HOMO (energy of the highest occupied molecular orbital energy) as well as high cytotoxicity against HepG2 cell line. This study affords an easily accessible approach for the synthesis of promising anticancer agents. The developed QSAR models provided pertinent information into the physicochemical properties governing the investigated biologic properties.     

Synthesis and structure-activity relationship of 2-thiopyrimidine-4-one analogs as antimicrobial and anticancer agents

Considering that some thiopyrimidines were previously reported as potential therapeutics, the present study achieved novel analogs of bioactive 2-substituted thiopyrimidines-4-(3H)-ones via base catalyzed alkylation reaction of 2-thiouracil using alkyl and aralkyl bromides. The title compounds were 2-(1-butylthio)pyrimidine-4(3H)-one (5a), 2-(2-butylthio)pyrimidine-4(3H)-one (5b), 2-(cyclohexylmethylthio)pyrimidine-4(3H)-one (5c), 2-(benzylthio)pyrimidine-4(3H)-one (5d) and 2-(1-adamantylthio)pyrimidine-4(3H)-one (5e). Bioactivity tests revealed that thiopyrimidines 5a, 5c, 5d and 5e exhibited antimicrobial activity. The thiopyrimidine-4-one (5c) showed complete inhibition against Streptococcus pyogenes and Branhamella catarrhalis as well as antifungal action against Candida albicans. Significantly, the 1-adamantylthiopyrimidine (5e) was shown to be the most potent cytotoxic compound against multidrug-resistant small cell lung cancer (H69AR). Their structure-activity relationships were discussed.     

Lymphocyte homeostasis in HIV-infected northern Thais

Cross-sectional laboratory data were used to model the patterns of total lymphocyte count and lymphocyte subpopulation counts among persons with chronic HIV-1 subtype E (CRF01_AE) infection during the 6.5 years preceding death. The data cover 331 HIV-infected decedents from a heterosexual HIV transmission study of 590 northern Thai couples enrolled in 1992-1998. From blood collected at enrollment, the lymphocyte phenotypes (CD3, CD8, CD4, natural killer, and B cells) were stained using two-color monoclonal antibody combinations and quantified by flow cytometry. Piecewise linear splines modeled the associations between lymphocyte levels and time before death. Mean CD3, CD8, and B cell levels showed no temporal associations from 6.5 to 2 years before death, but each declined significantly during the 2 years before death. CD3 levels declined 31.0% [95% confidence interval (-40.3%, -19.8%)] and CD8 levels declined 24.6% (-35.4%, -13.5%) annually in the 2 years prior to death. In contrast, CD4 and NK cell levels declined little from 6.5 to 4.5 years before death but declined significantly over the 4.5 years prior to death. CD4 levels declined 22.1% (-29.2%, -12.0%) annually from 4.5 to 2 years prior to death and 63.7% (-72.3%, -53.6%) annually over the remaining 2 years. Similar lymphocyte patterns have been reported in U. S. and European populations with HIV-1 subtype B infection.     

MicroRNAs regulate distal region of mandibular development through Hh signaling

Mandibular anomalies are often seen in various congenital diseases, indicating that mandibular development is under strict molecular control. Therefore, it is crucial to understand the molecular mechanisms involved in mandibular development. MicroRNAs (miRNAs) are noncoding small single-stranded RNAs that play a critical role in regulating the level of gene expression. We found that the mesenchymal conditional deletion of miRNAs arising from a lack of Dicer (an essential molecule for miRNA processing, Dicer^fl/fl;Wnt1Cre), led to an abnormal groove formation at the distal end of developing mandibles. At E10.5, when the region forms, inhibitors of Hh signaling, Ptch1 and Hhip1 showed increased expression at the region in Dicer mutant mandibles, while Gli1 (a major mediator of Hh signaling) was significantly downregulated in mutant mandibles. These suggest that Hh signaling was downregulated at the distal end of Dicer mutant mandibles by increased inhibitors. To understand whether the abnormal groove formation inDicer mutant mandibles was caused by the downregulation of Hh signaling, mice with a mesenchymal deletion of Hh signaling activity arising from a lack of Smo (an essential molecule for Hh signaling activation, Smo^fl/fl;Wnt1Cre) were examined. Smo^fl/fl;Wnt1Cre mice showed a similar phenotype in the distal region of their mandibles to those in Dicer^fl/fl;Wnt1Cre mice. We also found that approximately 400 miRNAs were expressed in wild-type mandibular mesenchymes at E10.5, and six microRNAs were identified as miRNAs with binding potential against both Ptch1 and Hhip1. Their expressions at the distal end of the mandible were confirmed by in situ hybridization. This indicates that microRNAs regulate the distal part of mandibular formation at an early stage of development by involving Hh signaling activity through controlling its inhibitor expression level.     

Discovery of novel halogenated 8-hydroxyquinoline-based anti-MRSA agents: In vitro and QSAR studies

Methicillin-resistant Staphylococcus aureus (MRSA) infection has been considered to be one of global health problems due to limited classes of effective antimicrobial drugs. Herein, 8-hydroxyquinoline (8HQ) and its derivatives ( 1-7 ) were investigated for their anti-MRSA and antioxidant activities. Cloxyquin ( 2 ), a halogenated 8HQ, exerted the highest antimicrobial activity (MIC₅₀ ≤ 5.57 μM) with high safety index, whereas an amino-derivative 7 showed the strongest antioxidant activity. Additionally, quantitative structure-activity relationship (QSAR) study demonstrated that mass, polarizability, topological charge, and van der Waals volume are essential properties governing the anti-MRSA activity. Taken together, cloxyquin was highlighted as a promising compound for further development as a novel anti-MRSA agent. QSAR findings would also benefit for further rational design of novel 8HQ-based compounds to combat the MRSA resistance.     

Attenuation of oxidative stress-induced neuronal cell death by Hydnophytum formicar-um Jack.

Objective: To investigate protective effects of Hydnophytum formicarum Jack.(H. formicarum) extracts via regulation of SIRT1-FOXO3a-ADAM10 signaling and antioxidant activity against H_2O_2-induced neurotoxicity in neuroblastoma SH-SY5Y cells. Methods: Cell viability and apoptosis of neuronal cells pretreated with H. formicarum Jack. extracts under oxidative stress were determined by MTT assay and flow cytometry. The intracellular reactive oxygen species(ROS) was performed using Carboxy-DCFDA assay. Additionally, a profile of protein expressions related to neuroprotection was detected by western blot analysis. Results: The plant extracts(methanol and ethyl acetate) elicited protective effects on the neuronal cell death as performed by the MTT assay and by apoptosis analysis via the activation of BCL-2. Both ethyl acetate and methanol extracts exerted inhibitory effects against H_2O_2-induced ROS generation in the SH-SY5Y cells. Furthermore, the possible mechanism of neuroprotection of H. formicarum Jack. was observed through its antioxidant properties by maintaining the levels of catalase and SOD2 proteins as well as activating SIRT1-FOXO3a pathway. Importantly, pretreatment of neuronal cells with H. formicarum Jack. significantly recovered the levels of ADAM10 protein compared with the H_2O_2 treatment alone. Conclusions: The recent findings suggest the protective effects of H. formicarum Jack. plant extracts on attenuating H_2O_2-induced neurotoxicity in human SH-SY5Y cells.     

Synthesis and cytotoxicity of novel 4-(4-(substituted)-1H-1,2,3-triazol-1-yl)-N-phenethylbenzenesulfonamides

A new series of 4-(4-(substituted)-1H-1,2,3-triazol-1-yl)-N-phenethylbenzenesulfonamide derivatives 5 were synthesized through the Click approach and evaluated for their cytotoxic activity against four cancer cell lines (HuCCA-1, HepG2, A549, and MOLT-3). Most of the synthesized triazoles 5 displayed cytotoxicity against MOLT-3 cell line, except for analogs 5a–c and 5e. Significantly, 4-phenyltriazoles (5a and 5n), 4-(naphthalen-2-yloxy)methyltriazole 5d, as well as 4-((2-oxo-2H-chromen-7-yl)oxy)methyltriazole 5l showed higher cytotoxic activity against HepG2 cells than the reference drug, etoposide. Interestingly, the 4-phenyltriazole 5a was the most potent and promising compound with IC₅₀ value of 9.07 μM against HepG2 cell line. The analog 5a also exerted the highest cytotoxic activity against HuCCA-1 cells. This finding provides the novel lead molecules for further development.