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Tran Quoc Hoa,1 Nguyen Ngoc Cuong,2 Nguyen Cong Hoan,3 Nguyen Quang Trung,2 Thieu Thi Tra My,4 Nguyen Ngoc Anh,5 Hoang Long1 1Surgery Urology, Hanoi Medical University Hospital, Hanoi Medical University, Hanoi, Vietnam; 2Radiology Center Hanoi Medical University Hospital, Hanoi Medical University, Hanoi, Vietnam; 3Outpatient department, Hanoi medical university hospital, Hanoi medical university, Hanoi, Vietnam; 4Radiology Department, Vinmec Times city Interational Hospital, Hanoi, Vietnam; 5Anatomy Department, Hanoi Medical University, Hanoi, VietnamCorrespondence: Nguyen Ngoc Cuong, Radiology center, Hanoi medical university hospital, No. 1, Ton That Tung Street, Dong Da District, Hanoi, Viet Nam, Tel +84965131314, Email cuongcdha@gmail.comPurpose: Chyluria is a rare condition primarily prevalent in developing countries in tropical regions. In chyluria, there exists the communication between lymphatic vessels and the urinary tract, but the specific mechanism of this communication remains undocumented. The objective of this study was to assess the morphology of the main lymphatic vessels including the uro-lymphatic fistula, the thoracic duct using Magnetic Resonance Lymphangiography (MRL) and Intranodal Lymphangiography (IL).Materials and Methods: A retrospective study spanning five years, from January 2020 to January 2024, included 43 patients diagnosed with chyluria through cystoscopy and quantitative urine testing for triglycerides. These patients underwent MRL and then IL for uro-lymphatic fistula embolization.Results: The study involved 43 patients with an average age of 66.1 ± 19.5 years, with a male-to-female ratio of 1:2. Uro-lymphatic fistula occurred predominantly in the left kidney (72.1%), followed by the right kidney (20.9%), and both sides (7%). MRL imaging showed the thoracic duct in 100% of cases but visualized only 84.5% of the uro-lymphatic fistulas. In contrast, IL imaging showed the thoracic duct in 51.5% of patients but visualized uro-lymphatic fistulas in 100% of cases. In the procedure of IL, the average visualization time of the thoracic duct was 45 minutes, with a range of 35 to 69 minutes.Conclusion: MRL and IL complement each other in diagnosing the main lymphatic vessels in chyluria patients. The observed circulatory stasis in the thoracic duct supports the hypothesis that it contributes to increased pressure in the thoracic duct and the formation uro-lymphatic fistula as collateral circulations.Keywords: chyluria, MR lymphangiography, intranodal lymphangiography, uro-lymphatic fistula

Nguyen Ngoc Cuong,1,* Le Hoan,2,* Thieu Thi Tra My,3 Doan Tien Luu,1 Le Tuan Linh,1 Pham Hong Canh,1 Trieu Quoc Tinh,1 Tran Nguyen Khanh Chi,1 Nguyen Quang Trung,1 Tran Quoc Hoa4 1Diagnostic Imaging and Interventional Center, Hanoi Medical University Hospital, Ha Noi, Viet Nam; 2Respiratory Department, Hanoi Medical University Hospital, Ha Noi, Viet Nam; 3Diagnostic Imaging and Nuclear Medicine Department, Vinmec Times City International Hospital, Ha Noi, Viet Nam; 4Urology Surgery department, Hanoi Medical university, Ha Noi, Viet Nam*These authors contributed equally to this workCorrespondence: Nguyen Ngoc Cuong, Diagnostic Imaging and Interventional Center, Hanoi Medical University Hospital, No. 1, Ton That Tung, Dong Da, Ha Noi, Viet Nam, Email Cuongcdha@gmail.comObjective: Chyle leak (CL) after head and neck surgery is a rare but well-known complication. In patients with high-output leakage, the treatment can be complicated. This study aims to report on a recent innovation in lymphatic intervention for treating such patients.Materials and Methods: A retrospective review of 36 patients with chyle leak after neck surgery for thyroid cancer was conducted to assess the efficacy of percutaneous lymphatic embolization and thoracic duct (TD) disruption.Results: Antegrade catheterization of the thoracic duct was achieved in 31 of 36 patients (86.1%). Therefore, embolization of the thoracic duct and thoracic duct branches was performed in 26 and 5 patients, respectively. In 5 cases of unsuccessful antegrade catheterization into the thoracic duct, transcervical access embolization was performed in 2 patients, and TD disruption (TDD) was performed in 3 patients. The pooled overall technical success rate of lymphatic embolization was 33/36 patients (91.7%). One patient who underwent thoracic duct embolization (TDE) with technical success (1/33 patients) but clinical failure had additional treatment directly sclerosing the TD under computed tomography scan. Cervical fluid collection sclerotherapy was done in 7 patients as an additional treatment. Resolution of the chyle leak after procedures was observed in all patients (100%). The mean time to resolution was 3 days (1– 7 days). There was no complication intra and after procedures.Conclusion: TDE, selective TD branches embolization and TDD are safe and effective minimally invasive treatments for CL post-surgery for thyroid carcinoma. Sclerosing cervical fluid collection contributes to clinical success.Keywords: thyroid cancer, thyroidectomy, chyle leak, thoracic duct embolization, thoracic duct disruption, sclerotherapy

Phytochemical investigation of the whole plants of Vernonia gratiosa Hance. led in the isolation and identification of two new stigmastane-type steroidal glucosides ( 1 - 2 ), namely vernogratiosides A ( 1 ), and B ( 2 ). Their chemical structures were fully elucidated based on 1 D/2D NMR spectroscopic, HR-ESI-MS data analyses, and by producing derivatives by chemical reactions. The binding potential of the isolated compounds to replicase protein - main protease of SARS-CoV-2 were examined using the molecular docking simulations. Our results show that the isolated steroidal glucosides ( 1 - 2 ) bind to the substrate-binding site of SARS-CoV-2 main protease with binding affinities of -7.2 and -7.6 kcal/mol, respectively, as well as binding abilities equivalent to N3 inhibitor that has already been reported (-7.5 kcal/mol).

Species belonging to the Vernonia (Asteraceae), the largest genus in the tribe Vernonieae (consisting of about 1,000 species), are widely used in food and medicine. These plants are rich sources of bioactive sesquiterpene lactones and steroid saponins, likely including many as yet undiscovered chemical components. A phytochemical investigation resulted in the separation of three new stigmastane-type steroidal saponins (1 - 3), designated as vernogratiosides A-C, from whole plants of V. gratiosa . Their structures were elucidated based on infrared spectroscopy (IR), one-dimensional (1D) and two-dimensional nuclear magnetic resonance (2D NMR), high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), and electronic circular dichroism analyses (ECD), as well as chemical reactivity. Molecular docking analysis of representative saponins with α-glucosidase inhibitory activity was performed. Additionally, the intended substances were tested for their ability to inhibit α-glucosidase activity in a laboratory setting. The results suggested that stigmastane-type steroidal saponins from V. gratiosa are promising candidate antidiabetic agents.

Two new compounds, named eudesm-4(15),7-diene-3α,9β,11-triol (1) and eudesm-4(15),7-diene-1β,3α,9β,11-tetraol (2) together with three known sesquiterpene lactones (1S,5R,7R,10R)-secoatractylolactone (3), (1S,5R,7R,10R)-secoatractylolactone-11-O-β-D-glucopyranoside (4) atractylenolide III (5) were isolated from the rhizomes of Atractylodes macrocephala. Their structures were elucidated by using one-dimensional (1D) and 2D-NMR spectra and high resolution electrospray ionization (HR-ESI)-MS data. Compound 5 exhibited the most active anti-inflammatory activity with IC 50 values of 27.5 µM in inhibiting of nitric oxide production. Compounds 1, 2, and 3 showed moderate effects while compound 4 was inactive.

Paederia scandens (Lour.) is a widely used medicinal herb in Vietnam, China, India, and Japan for the treatment of a variety of conditions, including toothache, chest pains, piles, and spleen inflammation. There is broad interest in identifying the composition of its extracts and confirming their numerous biological activities, including anti-nociceptive, antiviral, and anticancer properties. Two iridoid glucosides obtained from the MeOH extract of P. scandens , 6'-O- E -feruloylmonotropein (6-FMT) and 10'-O- E -feruloylmonotropein (10-FMT), are potential antioxidants based on their structure. In this study, the hydroperoxyl scavenging activity of 6-FMT and 10-FMT was examined in silico by using density functional theory. These FMTs are predicted to be weak antioxidants in non-polar environments, whereas a good HOO˙ scavenging activity is expected in polar environments (pH = 7.4) with k overall = 3.66 × 10 7 M -1 s -1 and 9.45 × 10 6 M -1 s -1 , respectively. This activity is better than many common antioxidants such as trolox and nearly equivalent to ascorbic acid and resveratrol. The hydroperoxyl scavenging activity was exerted mainly by the di-anion form of FMTs in water at physiological pH following the single electron transfer mechanism. The results suggest that FMTs are promising natural antioxidants in aqueous physiological environments., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Phytochemical investigation of a methanol extract of Panax pseudoginseng flower buds resulted in the isolation of 22 dammarane-type triterpenoid saponins, including three new compounds, pseudoginsenosides A-C ( 1 - 3 ), and 19 known analogs. Their chemical structures were identified by the comprehensive spectroscopic methods, including 1 D and 2 D NMR and mass spectra. In addition, their cytotoxic effects toward three human carcinoma cell lines, including liver (HepG2), breast (MCF7), and lung (A549) were also evaluated.

In this study, the performance of 17 different density functional theory functionals was compared for the calculation of the bond dissociation energy (BDE) values of X-H (X=C, N, O, S) bonds of aromatic compounds. The effect of the size of the basis set (expansions of 6-31(G)) was also assessed for the initial geometry and zero-point energy calculations, followed by the single-point BDE calculations with different model chemistries with the 6-311 + (3df,2p) basis set. It was found that the size of the basis set for geometry optimization has a much smaller effect on the accuracy of BDE than the choice of functional for the following single-point calculations. The M06-2X, M05-2X and M08-HX functionals yielded highly accurate BDE values compared to experimental data (with the average mean unsigned error MUE = 1.2-1.5 kcal mol -1 ), performing better than any of the other functionals. The results suggest that geometry optimization may be performed with B3LYP functional and a small basis set, whereas the M06-2X, M05-2X and M08-HX density functionals with a suitably large basis set offer the best method for calculating BDEs of ArX-H (X=C, N, O, S) bonds., (© 2022 The Authors.)

Background: Chronic hepatitis B virus (CHB) infection is a major health problem and leading cause of hepatocellular carcinoma (HCC) worldwide. Several point and deletion mutations on the PreS/S gene have been intensively considered associated with HCC. This study aimed to describe the characteristics of HBV PreS/S mutations in Vietnamese CHB-infected patients and their association with HCC., Methods: This cross-sectional study was conducted from 02/2020 to 03/2021, recruited Vietnamese CHB-infected patients with HBV-DNA >3 log10-copies/mL and successful PreS/S gene sequencing. Mutations were detected by direct Sanger sequencing., Results: 247 CHB-infected patients were recruited, characterized by 68.8% males, 54.7% HBV genotype B, 57.5% HBeAg positive, 23.1% fibrosis score ≥F3 and 19.8% HCC. 61.8% amino acid replacements were detected throughout the PreS1/PreS2/S genes. The most common point-mutations included N/H51Y/T/S/Q/P (30.4%), V68T/S/I (44.9%), T/N87S/T/P (46.2%) on PreS1 gene; T125S/N/P (30.8%), I150T (42.5%) on PreS2 gene; S53L (37.7%), A184V/G (39.3%), S210K/N/R/S (39.3%) on S gene. The rates of case(s) with any point-mutation on the Major Hydrophylic Region (MHR) and the "a" determinant region were 63.6% and 39.7%, respectively. Most of S point-mutations were presented with low rates such as T47A/E/V/K (9.3%), P120S/T (8.5%), G145R (2%). On multivariable analysis, males (OR = 4.51, 95%CI 1.78-11.4, p = 0.001), age≥40 (OR = 5.5, 95%CI 2.06-14.68, p = 0.001), W4P/R/Y on PreS1 (OR = 11.56, 95%CI 1.99-67.05, p = 0.006) and 4 S point-mutations as: T47A/E/V/K (OR = 3.67, 95%CI 1.19-11.29, p = 0.023), P120S/T (OR = 3.38, 95%CI 1.09-10.49, p = 0.035), S174N (OR = 29.73, 95%CI 2.12-417.07, p = 0.012), P203R (OR = 8.45, 95%CI 1.43-50.06, p = 0.019) were associated with HCC., Conclusions: We detected 61% amino acid changes on PreS/S regions in Vietnamese CHB patients. One point-mutation at amino acid 4 on PreS1 gene and 4 point-mutations at amino acids 47, 120, 174, and 203 on S gene were associated with HCC. Further investigations are recommended to further clarify the relationship and interaction between mutations in HBV genome and HCC progression., Competing Interests: The authors have declared that no competing interests exist.

Illicit drug use is a serious issue in Vietnam, but information about their prevalence is scarce, mainly based on seizure data. Wastewater-based epidemiology (WBE) is an alternative tool for obtaining such information, especially when stigma related to drug use can hinder survey approaches. The study aimed to apply WBE to assess the prevalence of use of a range of illicit drugs in an urban population of Vietnam. A total of 184 wastewater samples were collected at two different sites along a sewage canal, receiving sewage from over 400,000 people in Hanoi, Vietnam, in three different periods between 2018 and 2020. Illicit drugs and their metabolites were measured by direct injection using liquid chromatography-tandem mass spectrometry. The results were back-estimated, normalised to per capita daily consumption for assessement of consumption patterns and trends. Most drugs were detected in all the samples except cocaine, benzoylecgonine, amphetamine indicating a low prevalence of cocaine and amphetamine use. The estimated consumption level of methamphetamine was varied from 119.5 to 553.5 mg/d/1000 pp. The market of illicit drugs in Vietnam has changed from opiates to amphetamine-type simulants, and methamphetamine has replaced heroin as the No.1 drug, its use can be as much as 3 times more than heroin use. Moreover, we observed the considerable and potentially increasing level of ketamine consumption in Hanoi. No statistical difference was found in daily consumption per capita among days of the week for any drugs, both legal (codeine, methadone) and illegal (methamphetamine, MDMA, ketamine and heroin), suggesting the drugs were consumed mainly by regular users. This study provides important information related the illicit drug consumption in Vietnam, which will help to formulate appropriate drug control policies in this country., Competing Interests: Declaration of competing interest Authors declare no competing interests., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Oxoberberine (OB, 2,10-dihydroxy-3,9-dimethoxy-8-oxo-protoberberine, artathomsonine), which was isolated from Artabotrys thomsonii, was shown to exhibit potent antioxidant activity in vitro , however that is the only reported evidence of the radical scavenging activity of this compound thus far. In the present study, thermodynamic and kinetic calculations were used to determine the free radical scavenging activity of OB against a range of biologically important species, under physiological conditions. In the first part the activity is calculated against the HOO˙ radical that is both biologically important and a reference radical for comparison. It was found that OB has high antiradical capacity against HOO˙ in both lipid medium and water at physiological pH with k overall = 1.33 × 10 5 and 1.73 × 10 6 M -1 s -1 , respectively. The formal hydrogen transfer mechanism defined the activity in nonpolar environments, whereas in the aqueous solution the single electron transfer competes with the hydrogen transfer pathway. The results showed that, in lipid medium, the HOO˙ trapping capability of OB is better than typical antioxidants such as Trolox, BHT, resveratrol and ascorbic acid. Similarly, the activity of OB in water at pH 7.4 is roughly 19 and 7 times faster than those of Trolox and BHT, respectively, but slightly lower than the activities of resveratrol or ascorbic acid. In the second part, it was found that OB also exhibits high activity against other typical free radicals such as CH 3 O˙, CH 3 OO˙, CCl 3 OO˙, NO 2 , SO 4 ˙ - , DPPH and ABTS˙ + with k f ranging from 2.03 × 10 5 to 5.74 × 10 7 M -1 s -1 . Hence, it is concluded that OB is a promising radical scavenger in the physiological environment., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Chemical investigation of a peanut-associated fungal strain Aspergillus niger IMBC-NMTP01 resulted in isolation and identification of 14 secondary metabolites, including two new, epi -aspergillusol ( 1 ) and aspernigin ( 3 ), and 12 known compounds: pyrophen ( 2 ), 2-(hydroxyimino)-3-(4-hydroxyphenyl)propanoic acid ( 4 ), aspergillusol A ( 5 ), rubrofusarin B ( 6 ), nigerasperone A ( 7 ), fonsecin ( 8 ), TMC-256C1 ( 9 ), pyranonigrin A ( 10 ), orlandin ( 11 ), nigerasperone C ( 12 ), asperpyrone A ( 13 ), and 5-(hydroxymethyl)-2-furancarboxylic acid ( 14 ). Compounds 9 , 12-14 showed cytotoxicity toward all six human cancer cell lines, including HepG2, KB, HL-60, MCF-7, SK-Mel2, and LNCaP, with IC 50 values ranging from 8.4 to 84.5 µM, compounds 3-5 were cytotoxic against five cancer cell lines except HepG2, whereas 1 exhibited cytotoxicity toward HepG2, KB, and MCF-7 cells. All of the compounds, except 2 and 13 , inhibited NO overproduction in LPS-induced RAW264.7 cells. In addition, all of the compounds displayed antimicrobial effects against Enterococcus faecalis , whereas 13 compounds, except 10 , significantly inhibited the growth of the yeast Candida albican s.

Anthraquinones (ANQs) isolated from Paederia plants are known to have antidiarrheal, antitussive, anthelmintic, analgesic, anti-inflammatory, antihyperlipidemic, antihyperglycaemic, and antimicrobial activities. The antioxidant properties were also noted but not confirmed thus far. In this study, the superoxide and hydroperoxide radical scavenging activities of six ANQs were evaluated using a computational approach. The results suggest that the ANQs exhibit low HOO • antiradical activity in all environments, including the gas phase ( k < 10 2 M -1 s -1 ). In contrast, the ANQs might exert excellent O 2 •- radical scavenging activity, particularly in aqueous solution. The rate constants of the superoxide anion scavenging in water (at pH = 7.4) range from 3.42 × 10 6 to 3.70 × 10 8 M -1 s -1 . Compared with typical antioxidants such as ascorbic acid and quercetin, the superoxide anion scavenging activity of ANQs is significantly higher. Thus, the ANQs are promising O 2 •- radical scavengers in polar media., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Background: Nasopharyngeal carcinoma (NPC) is a rare epithelial carcinoma arising from the nasopharyngeal region. The pathogenesis of NPC is linked to Epstein-Barr virus (EBV) infection, although genetics and lifestyle factors appears to be also implicated. NKG2D is an immunoreceptor expressed by NK and T-cell subsets that recognizes MICA protein and other ligands on tumor cells. NKG2D interaction with MICA plays a role in the immunosurveillance to viruses and cancer., Methods: We investigated potential associations between functional polymorphisms in NKG2D and MICA genes with NPC susceptibility. We conducted a case-control study including 255 Vietnamese patients with EBV + non-differentiated NPC and 220 healthy controls., Results: We observed a significant association between the LNK/LNK genotype of rs1049174 (a variant associated with lower NKG2D receptor expression and reduced NK cell cytotoxicity) and increased susceptibility to NPC (adjusted OR = 1.66, 95% CI 1.07-2.59; p = 0.024). Similarly, the AA genotype of MICA rs2596542 was significantly associated with NPC (adjusted OR = 2.12; 95% CI 1.22-3.81; p = 0.009). In addition, tumor specimens of NPC patients with the AA genotype displayed a higher expression level of MICA proteins and showed higher EBV titers compared with tumor tissues from patients with the GG or GA genotypes. Higher EBV copy numbers were also observed in tumors with the A allele of MICA rs1051792 (also known as MICA-129 Met/Val) compared with those with the G allele; however, MICA rs1051792 variants were not associated with NPC susceptibility. These results suggest that genetic variants in components of the NKG2D axis may influence the individual susceptibility to EBV-induced NPC.

The use of Near Infrared Spectroscopy (NIRS) as a fast and non-destructive technique was employed for the control and monitoring of the tableting step during a continuous manufacturing process. Two NIRS methods were optimized in order to in-line control the blend uniformity in the tablet feed frame and the API concentration of freshly pressed tablets prior the ejection. The novelty of this work first lies in the acquisition speed of NIR spectra reaching up to 70,000 tablets/h. Partial Least Square (PLS) regression was used as chemometric tool for the computation that resulted in excellent predictive calibration results. A coefficient of correlation (r) value of 0.99 was obtained for both probes. The root mean square error of calibration (RMSEC) and the root mean square error of prediction (RMSEP) were respectively 1.8% and 1.8% for active content in the tablet feeder and 2.2% and 2.3% for the tablet content. In addition, calibration performance and robustness of the methods were evaluated. Moreover several qualitative methods were proposed to monitor the tableting process in different stages of development (single wavelength, Principal Component Analysis, and Independent Component Analysis). In early phase development, the requirement/quality of the input material is not established yet; hence the use of a qualitative approach allows to confirm the suitability of the PAT methodology for in-process material monitoring & control. Later, the qualitative approach constitutes the foundation for the quantitative approach when input materials are fixed and larger production size occurs. The proposed strategy is a performant PAT tool for continuous manufacturing and a step forward to real time release., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Two new guaiane sesquiterpene lactones, vulgarolides A and B (1 and 2), were isolated from Artemisia vulgaris aerial parts using various chromatographic separations. The structure elucidation was performed by combination of spectroscopic experiments including 1D and 2D NMR, HR ESI MS, and CD. Their in vitro cytotoxic activities against five human cancer cell lines were also evaluated using SRB method.

In field survey, Pteris vittata and Pityrogramma calomelanos were only found in arsenic (As) contaminated areas with soil pH 7.2-8.8 and 2.3-4.2, respectively. In the first pot experiment, two fern species were grown on the soil amended with 300 mg kg -1 As at soil pH of 5.1, 7.2 and 9. P. calomelanos survived all pH treatments, and had the highest frond As concentration and soil As removal efficiency at soil pH 5.1. All P. vittata plants were dead at soil pH 5.1. P. vittata had higher frond As concentration, biomass and the amount of As removed from the soil than those of P. calomelanos at soil pH of 7.2 and 9. In the second pot experiment, P. vittata was demonstrated to have greater life time, biomass, As tolerance and accumulation than those of P. calomelanos as planted on alkaline soil (pH 7.8) spiked with various concentrations of As.

The consumption of fuel by vehicles emits nitrogen oxides (NOx) and non-methane hydrocarbons (NMHCs) into the atmosphere, which are important ozone precursors. Ozone is formed as a secondary pollutant via photochemical processes and is not emitted directly into the atmosphere. In this paper, the ozone increase resulting from the use of biodiesel and diesel fuels was investigated, and the different ozone formation trends were experimentally evaluated. Known amounts of exhaust gas from a power generator operated using biodiesel and diesel fuels were added to ambient air. The quality of the ambient air, such as the initial NMHC and NOx concentrations, and the irradiation intensity have an effect on the ozone levels. When 30 cm(3) of biodiesel fuel exhaust gas (BFEG) or diesel fuel exhausted gas (DFEG) was added to 18 dm(3) of ambient air, the highest ratios of ozone increase from BFEG compared with DFEG in Japan and Vietnam were 31.2 and 42.8%, respectively, and the maximum ozone increases resulting from DFEG and BFEG compared with the ambient air in Japan were 17.4 and 26.4 ppb, respectively. The ozone increase resulting from the use of BFEG was large and significant compared to that from DFEG under all experimental conditions. The ozone concentration increased as the amount of added exhaust gas increased. The ozone increase from the Jatropha-BFEG was slightly higher than that from waste cooking oil-BFEG., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Heterometallics are an important class of catalysts. Alloy nanoparticles have higher activities than monometallic counterparts in catalysis because of the synergistic effects between the two metals. The Ni-Co composition, which is a typical alloy chemical composition, has a remarkable effect on catalytic activity. Ni-Co mixed oxides were characterized by thermal effect, X-ray diffraction, energy dispersive X-ray spectroscopy, Scanning Electron Microscope and BET specific surface area techniques. X-ray diffraction show that the formation of small spinel oxides nanoparticles. Very small amounts of gold-silver alloy nanoparticles deposited on such mixed oxides improve the catalytical activity for CO oxidation.

3'-(α-L-Aminoacylamido)deoxyadenosines are ribosomal A-site binders and mimic the nascent peptide accepting 3'-terminus of aminoacyl transfer RNA. Their α-amino groups exhibit intrinsic basicities in bulk water that differ by up to 1.8 pK(a) units. Only the neutral form of these nucleophiles can be active during ribosomal peptidyl transfer catalysis.

Peptide dendrimers built by iteration of the diamino acid dendron Dap-His-Ser (His = histidine, Ser = Serine, Dap = diamino propionic acid) display a strong positive dendritic effect for the catalytic hydrolysis of 8-acyloxypyrene 1,3,6-trisulfonates, which proceeds with enzyme-like kinetics in aqueous medium (Delort, E.; Darbre, T.; Reymond, J.-L. J. Am. Chem. Soc. 2004, 126, 15642-3). Thirty-two mutants of the original third generation dendrimer A3 ((Ac-His-Ser)8(Dap-His-Ser)4(Dap-His-Ser)2Dap-His-Ser-NH2) were prepared by manual synthesis or by automated synthesis with use of a Chemspeed PSW1100 peptide synthesizer. Dendrimer catalysis was specific for 8-acyloxypyrene 1,3,6-trisulfonates, and there was no activity with other types of esters. While dendrimers with hydrophobic residues at the core and histidine residues at the surface only showed weak activity, exchanging serine residues in dendrimer A3 against alanine (A3A), beta-alanine (A3B), or threonine (A3C) improved catalytic efficiency. Substrate binding was correlated with the total number of histidines per dendrimer, with an average of three histidines per substrate binding site. The catalytic rate constant kcat depended on the placement of histidines within the dendrimers and the nature of the other amino acid residues. The fastest catalyst was the threonine mutant A3C ((Ac-His-Thr)8(Dap-His-Thr)4(Dap-His-Thr)2Dap-His-Thr-NH2), with kcat = 1.3 min(-1), kcat/k(uncat) = 90'000, KM = 160 microM for 8-bytyryloxypyrene 1,3,6-trisulfonate, corresponding to a rate acceleration of 18'000 per catalytic site and a 5-fold improvement over the original sequence A3.

Objective: To evaluate the effect of combined iron-zinc supplementation on micronutrient status, growth and morbidity., Design: Randomized, double-masked, placebo-controlled supplementation trial., Setting: Rural district of Que Vo, in the Red River Delta in Vietnam., Subjects: A total of 915 breast-fed infants aged 4-7 months were included and 784 completed the study., Interventions: The Fe-group received daily and for a 6-month period 10 mg of iron, the Zn-group 10 mg zinc, the Fe-Zn group 10 mg iron+10 mg zinc and the placebo group a placebo. Hemoglobin (Hb), serum ferritin (SF) and zinc (SZn), and anthropometry were measured before and at the end of the intervention. Morbidity was recorded daily., Results: Changes of Hb and SF were higher in both Fe and Fe+Zn groups (respectively 22.6 and 20.6 g/l for Hb; 36.0 and 24.8 microg/l for SF) compared to Zn and placebo groups (Hb: 6.4 and 9.8 g/l; SF: -18.2 and -16.9 microg/l, P<0.0001). SZn increased more in Zn group (10.3 micromol/l) than in Fe+Zn group (8.0 micromol/l, P=0.03) and more in these groups compared to Fe and placebo groups (1.6 and 1.2 micromol/l, P<0.0001). Weight gain was higher in the Zn group. No significant effects of supplementations on growth in length or morbidity., Conclusions: Combined iron-zinc supplementation had a positive effect on iron and zinc status in infants. However, the positive effect of zinc alone on SZn and weight would indicate a negative interaction of iron when added to zinc supplements., Sponsorship: UNICEF New York.

[reaction: see text] An efficient procedure for the immobilization of 3'-deoxy-3'-(O-methyltyrosyl)aminoadenosine was developed. A poly(ethylene glycol)-derived diacid linker/spacer was attached to aminomethyl polystyrene. Coupling of the 2'-hydroxy instead of the 2'-O-succinylated ribonucleoside resulted in high immobilization yields (over 80%) and allowed for the recovery of valuable unreacted material. This specific procedure should be applicable to other ribonucleosides containing a bulky modification at the 3'-position and can be used for the stepwise construction of 3'-aminoacyl- or 3'-peptidyl-RNA conjugates.

3'-aminoacylamino-3'-deoxyadenosines, analogues of the antibiotic puromycin, have been synthesized from adenosine. They key 3'-azido derivative 10 was obtained through a 3'-oxidation/reduction/substitution procedure. A modified purification protocol on a larger scale was developed for the oxidation step using the Garegg reagent. The coupling reaction between an Fmoc-l-amino acid and the fully protected form of 3'-amino-3'-deoxyadenosine 11 furnished the aminoacylated compounds 12 in high yields. The puromycin analogues were obtained in 10 steps and up to 23% (14c) overall yield.