Traditional medical practices for children in five islands from the Society archipelago (French Polynesia).

BACKGROUND: Traditional Polynesian medicine for children has been poorly documented, and few data are available on their efficacy and safety. In this context, the aim of this study was to identify traditional practices used for treating children and then assess the efficacy and safety of the most cited remedies by reviewing the literature. METHODS: In 2022, a semi-structured survey was carried out on five islands from the Society archipelago (Bora Bora, Huahine, Moorea, Raiatea, and Tahiti). A total of 86 participants were interviewed including 19 experts in herbalism. A thorough literature review was performed on the most cited plant species to gather the relevant ethnobotanical, pharmacological, and clinical data of each remedy. RESULTS: Participants mentioned using 469 remedies to treat 69 health disorders. The most represented health categories were digestive system, skin disorders, infectious diseases, and respiratory system. A total of 67 plant species (representing 731 use-reports) were mentioned and Annona muricata, Gardenia taitensis, and Hibiscus rosa-sinensis were the main plants reported. Regarding the safety of cited remedies, one plant (Microsorum grossum) showed high risk of toxicity, and its use should be avoided in infants and children. CONCLUSION: Our survey confirms the importance of traditional medical practices for children in the Society Islands. A lack of data in children for most cited remedies demonstrate the need for more pharmacological and toxicological research on Polynesian medicinal plants. Finally, the potential risk of toxicity for some cited plant species reported calls for a better information of traditional medicine users and healers.

Genetic factors for differentiated thyroid cancer in French Polynesia: new candidate loci.

Background: Populations of French Polynesia (FP), where France performed atmospheric tests between 1966 and 1974, experience a high incidence of differentiated thyroid cancer (DTC). However, up to now, no sufficiently large study of DTC genetic factors in this population has been performed to reach definitive conclusion. This research aimed to analyze the genetic factors of DTC risk among the native FP populations. Methods: We analyzed more than 300 000 single nucleotide polymorphisms (SNPs) genotyped in 283 DTC cases and 418 matched controls born in FP, most being younger than 15 years old at the time of the first nuclear tests. We analyzed the genetic profile of our cohort to identify population subgroups. We then completed a genome-wide analysis study on the whole population. Results: We identified a specific genetic structure in the FP population reflecting admixture from Asian and European populations. We identified three regions associated with increased DTC risk at 6q24.3, 10p12.2, and 17q21.32. The lead SNPs at these loci showed respective p-values of 1.66 × 10-7, 2.39 × 10-7, and 7.19 × 10-7 and corresponding odds ratios of 2.02, 1.89, and 2.37. Conclusion: Our study results suggest a role of the loci 6q24.3, 10p12.2 and 17q21.32 in DTC risk. However, a whole genome sequencing approach would be better suited to characterize these factors than genotyping with microarray chip designed for the Caucasian population. Moreover, the functional impact of these three new loci needs to be further explored and validated.

Effect of continuous in-feed administration of tylosin to feedlot cattle on macrolide and tetracycline resistant enterococci in a randomized field trial.

Liver abscess causes substantial economic loss to the beef cattle industry through liver condemnation, reduced animal performance, and carcass yield. Continuous in-feed use of tylosin is the most effective and a commonly used practice in beef cattle production to prevent liver abscess. However, such mass medication can increase the level of antimicrobial resistant bacteria. We investigated the effect of continuous in-feed use of tylosin in feedlot cattle on (i) concentrations and prevalence of erythromycin-resistant (ERYr) and tetracycline-resistant (TETr) enterococci; (ii) associated antimicrobial resistance genes (ARGs) for resistance; (iii) species distribution; iv) macrolide and tetracycline resistance gene concentrations; and (v) tylosin concentration. A cohort of weaned calves were randomized to receive tylosin-medicated feed (Tylosin; n = 10) or nonmedicated feed (Control; n = 10) for a full feedlot cycle. Feces, feed and pen-surface samples were collected and processed by culture, droplet digital PCR, and liquid chromatography/mass spectroscopy for bacterial enumeration, detection and characterization, ARG quantification, and tylosin concentration, respectively. Data were analyzed by mixed effects linear- or binary-regression models depending on the outcomes. Tylosin administration significantly increased fecal concentration (P < 0.001) and prevalence (P = 0.021) of ERYr enterococci and erm(B) gene concentration (P < 0.001), compared to the control group. Interestingly, tylosin administration significantly reduced (P = 0.037) fecal TETr enterococci concentration compared to the control group, with no significant effect (P = 0.758) on fecal tet(M) concentration. In both treatment groups, enterococci concentrations increased over time, peaking on 174 days in feed before returning to the baseline. ERYr enterococci concentration was significantly (P = 0.012) higher in tylosin medicated feeds, with no significant effect (P = 0.321) on TETr enterococci concentration. Pen-surface concentration of ermB was significantly (P = 0.024) higher in the tylosin group, with no significant effect (P > 0.05) on bacterial concentrations. Increased diversity and a shift in the composition of enterococcal species and ARGs were observed over time, although tylosin use did not significantly affect (P > 0.05) their prevalence. Tylosin concentration was significantly higher in the feces of tylosin administered cattle (P < 0.001) and medicated feed (P = 0.027), with numerically higher pen-surface concentration (P = 0.065) in the tylosin group. In conclusion, continuous in-feed use of tylosin in feedlot cattle increases macrolide resistant enterococci and its fecal excretion, while decreasing tetracycline resistance. Two medically important species, E. faecium and E. faecalis, were predominant regardless of resistance status or sample source. Risk-based approaches including label changes to limit tylosin use such as withdrawal period, and development of effective manure treatments are potential areas of research to reduce environmental and public health impacts.

Unravelling the determinants of human health in French Polynesia: the MATAEA project.

Background: French Polynesia is a French overseas collectivity in the Southeast Pacific, comprising 75 inhabited islands across five archipelagoes. The human settlement of the region corresponds to the last massive migration of humans to empty territories, but its timeline is still debated. Despite their recent population history and geographical isolation, inhabitants of French Polynesia experience health issues similar to those of continental countries. Modern lifestyles and increased longevity have led to a rise in non-communicable diseases (NCDs) such as obesity, diabetes, hypertension, and cardiovascular diseases. Likewise, international trade and people mobility have caused the emergence of communicable diseases (CDs) including mosquito-borne and respiratory diseases. Additionally, chronic pathologies including acute rheumatic fever, liver diseases, and ciguatera, are highly prevalent in French Polynesia. However, data on such diseases are scarce and not representative of the geographic fragmentation of the population. Objectives: The present project aims to estimate the prevalence of several NCDs and CDs in the population of the five archipelagoes, and identify associated risk factors. Moreover, genetic analyses will contribute to determine the sequence and timings of the peopling history of French Polynesia, and identify causal links between past genetic adaptation to island environments, and present-day susceptibility to certain diseases. Methods: This cross-sectional survey is based on the random selection of 2,100 adults aged 18-69 years and residing on 18 islands from the five archipelagoes. Each participant answered a questionnaire on a wide range of topics (including demographic characteristics, lifestyle habits and medical history), underwent physical measurements (height, weight, waist circumference, arterial pressure, and skin pigmentation), and provided biological samples (blood, saliva, and stool) for biological, genetic and microbiological analyses. Conclusion: For the first time in French Polynesia, the present project allows to collect a wide range of data to explore the existence of indicators and/or risk factors for multiple pathologies of public health concern. The results will help health authorities to adapt actions and preventive measures aimed at reducing the incidence of NCDs and CDs. Moreover, the new genomic data generated in this study, combined with anthropological data, will increase our understanding of the peopling history of French Polynesia. Clinical trial registration: https://clinicaltrials.gov/, identifier: NCT06133400.

Medication Adherence in Hypertensive Individuals in Panama 2019: A National Cross-Sectional Study.

Poor medication adherence is a public health concern leading to a large burden of cardiovascular disease among persons with hypertension. Using data from 3281 persons with diagnosed hypertension (N = 622,581) from the Panamanian National Health Survey (ENSPA) collected in 2019, we assessed the national prevalence of low-moderate medication adherence in hypertensive individuals using the 4-scale Morisky Medication Adherence Scale (4-MMAS) and identifying gender-specific associated factors. Multivariate logistic regression models were used to estimate the association between possible risk factors and low-moderate medication adherence with odds ratios (OR) and 95% confidence intervals (95% CI) stratified by gender. The national prevalence of low-moderate medication adherence was 78.2% (95% CI: 74.7-81.0%); in men it was 74.4% (95% CI: 67.5-80.3%) and in women it was 81.4% (78.4-84.0%). In women, low-moderate medication adherence was associated with living in indigenous area (OR: 5.15; 95% CI: 1.40-18.98), educational level (OR no formal education: 0.77, 95% CI 0.28-2.14; OR for primary education: 0.76, 95% CI 0.38-1.56; OR for secondary education: 0.90, 95% CI 0.48-1.70; Higher education as reference), increased BMI (normal as reference, OR for overweight: 1.35, 95% CI: 0.73-2.50, OR for obesity: 1.65, 95% CI: 0.90-3.03) and medical diagnosis of anxiety/depression (OR: 4.89, 95% CI: 1.36-17.49). However, in men, it was associated with having secondary education (OR: 2.94; 95% CI: 1.03-8.36), currently smoking (OR: 16.74, 95% CI: 1.83-152.70), taking antihypertensive medication with denial of hypertension diagnosis (OR: 4.35, 95% CI: 1.11-17.11) and having less than three annual check-ups (OR for no health check-ups: 2.97, 95% CI: 0.63-13.88; OR for 1-2 check-ups: 1.61, 95% CI: 0.78-3.32: three or more health check-ups: reference). Time since diagnosis was inversely associated with low-moderate adherence. This study assesses for the first time the national prevalence of low-moderate medication adherence among hypertensive individuals in Panama. Low-moderate medication adherence is an important public health issue that should be addressed to achieve blood pressure control in patients diagnosed with hypertension, taking into account gender-specific factors.

Lagoon, Anaerobic Digestion, and Composting of Animal Manure Treatments Impact on Tetracycline Resistance Genes.

Increased demand for animal protein is met by increased food animal production resulting in large quantities of manure. Animal producers, therefore, need sustainable agricultural practices to protect environmental health. Large quantities of antimicrobials are used in commercial food animal production. Consequently, antimicrobial-resistant bacteria and the resistance genes emerge and are excreted through feces. Manure management is essential for the safe disposal of animal waste. Lagoons, with or without covers, and anaerobic digesters, with the primary purpose of methane production, and composting, with the primary purpose of producing organic fertilizer, are widely used methods of manure treatment. We reviewed manure management practices and their impact on tetracycline resistance genes. Lagoons are maintained at ambient temperatures; especially uncovered lagoons are the least effective in removing tetracycline resistance genes. However, some modifications can improve the performance of lagoons: sequential use of uncovered lagoons and the use of covered lagoons resulted in a one-log reduction, while post-treatments such as biofiltration following covered lagoon treatment resulted in 3.4 log reduction. Mesophilic digestion of animal manure did not have any significant effect; only a 0.7 log reduction in tet(A) was observed in one study. While thermophilic anaerobic digesters are effective, if properly operated, they are expensive for animal producers. Aerobic thermophilic composting is a promising technology if optimized with its economic benefits. Composting of raw animal manure can result in up to a 2.5 log reduction, and postdigestion composting can reduce tetracycline resistance gene concentration by >80%. In general, manure management was not designed to mitigate antimicrobial resistance; future research is needed to optimize the economic benefits of biogas or organic fertilizer on the one hand and for the mitigation of foodborne pathogens and antimicrobial resistance on the other.

Polynesian medicine used to treat diarrhea and ciguatera: An ethnobotanical survey in six islands from French Polynesia.

ETHNOPHARMACOLOGICAL RELEVANCE: In French Polynesia, many pathologies common or endemic to the territory cause diarrhea. This is the case for rotavirus gastroenteritis, salmonella food poisoning, ingestion of water contaminated by bacteria, and ciguatera. To treat these ailments, the population may employ traditional medicine for cultural reasons, geographical isolation, and poor health coverage. Polynesian remedies are often used without medical consultation and there is no data on their benefit-risk balance. A few ethnobotanical studies have been carried out in order to identify the traditional remedies used for various ailments, but few studies have focused on gastrointestinal pathologies. In this context, an ethnobotanical survey was carried out to identify treatments used for diarrhea and ciguatera, inventory the plants used, better understand the local representation of these remedies, and provide efficacy and safety data on these uses. MATERIALS AND METHODS: From February to April 2021, a semi-structured survey was conducted on six islands in French Polynesia, including one island in the Windward Islands archipelago (Tahiti), three islands in the Marquesas archipelago (Hiva Oa, Nuku Hiva, Tahuata), and two islands in the Leeward Islands archipelago (Raiatea, Tahaa). A total of 133 people was interviewed including 34 specialists (of which 29 experts in herbalism). RESULTS: These people mentioned the use of 27 plants for the treatment of diarrhea, and 24 for the treatment of ciguatera. Citrus aurantiifolia, Psidium guajava and Cordyline fruticosa were the three most cited plant species used for treating diarrhea, while Cocos nucifera, Punica granatum and Barringtonia asiatica were the most cited for ciguatera. A large majority of plants are widespread and introduced plants, which is congruent with the history of Polynesian people. While some plants are well known for similar uses (e.g. Psidium guajava for diarrhea, Heliotropium arboreum for ciguatera), others are less well known and may present toxicity risks (e.g. Barringtonia asiatica for ciguatera). CONCLUSION: Traditional Polynesian medicine is an integral part of the local culture so important to be preserved and valued. However, more pharmacological and toxicological studies are still needed to determine the benefit-risk balance of some of these remedies and to allow their official integration into the Polynesian health system.

Dosis Diaria Definida de antibióticos en pacientes atendidos en hospitales públicos de Panamá

Objetivo: Determinar la Dosis Diaria Definida (DDD) de antibióticos utilizados en los Servicios de Medicina Interna de cuatro hospitales públicos en Panamá. Métodos: Se escogió una muestra a conveniencia de 4 hospitales públicos de segundo nivel de atención de la seguridad social y Ministerio de Salud, atendiendo características en cuanto a ubicación en provincias, población atendida, servicios médicos ofrecidos y con Dosis Unitaria en funcionamiento. Se obtuvieron datos de los pacientes hospitalizados entre los meses de enero a marzo del 2017 y la información era registrada en una base de datos anotándose generales del paciente, diagnósticos, antibióticos, dosis, frecuencia, tiempo de tratamiento. Igualmente se anotaron los consumos y costos unitarios de todos los antibióticos usados en los hospitales durante el año 2016, para calcular la DDD y Dosis Diaria Prescrita. Resultados: La oxacilina fue el antibiótico con mayor DDD días cama con 60.5, luego le siguen ceftriaxona (45.2), cefalotina (35.5), clindamicina (35.5). Por grupo farmacológico, las cefalosporinas tienen consumos más altos con 87.6 DDD días cama, la penicilina MRSA 60.5, la lincosamidas con 35.5 DDD días cama, seguido de las quinolonas con 29.3. Conclusiones: Los resultados pueden ser utilizados para implementar programas para mejorar el uso racional y gasto de antibióticos a nivel hospitalario y que la DDD se use para medir el consumo y a la vez propiciar el control de antibióticos a través de comunicaciones escritas con los médicos tratantes. Se deben realizar estudios de DDD días cama relacionando con los aspectos microbiológicos para relacionar mejor el uso de los antibióticos. (provisto por Infomedic International)

Objective. Determine the Defined Daily Dose of antibiotics used in the Internal Medicine Services of 4 public hospitals in Panama. Methods. A convenience sample of 4 public hospitals of the second level of social security care and the Ministry of Health was chosen, considering characteristics in terms of location in the provinces, population served, medical services offered and with Unit Dose in operation. Data were obtained from hospitalized patients between the months of January to March 2017 and the information was recorded in a database, noting general patient reports, diagnoses, antibiotics, dose, frequency, treatment time. Likewise, the consumptions and unit costs of all antibiotics used in hospitals during 2016 were recorded to calculate the DDD and Prescribed Daily Dose. Results. Oxacillin was the antibiotic with the highest DDD bed days with 60.5, followed by ceftriaxone (45.2), cephalothin (35.5), and clindamycin (35.5). By pharmacological group, cephalosporins have higher intakes with 87.6 DDD bed days, penicillin MRSA 60.5, and lincosamides with 35.5 DDD bed days, followed by quinolones with 29.3. Conclusions. The results can be used to implement programs to improve the rational use and expense of antibiotics at the hospital level and that the DDD is used to measure the consumption and at the same time promote the control of antibiotics through written communications with the treating physicians. Bed-day DDD studies should be carried out relating to microbiological aspects to better relate the use of antibiotics. (provided by Infomedic International)

Anaerobic Digestion of Tetracycline Spiked Livestock Manure and Poultry Litter Increased the Abundances of Antibiotic and Heavy Metal Resistance Genes.

Anaerobic digestion is used for the treatment of animal manure by generating biogas. Heavy metals cause environmental pollutions and co-select for antimicrobial resistance. We evaluated the impact of mesophilic anaerobic digestion of cattle manure (CM), swine manure (SM) and poultry litter (PL) on the concentrations of seven tetracycline [tet(A), tet(B), tet(G), tet(M), tet(O), tet(Q), and tet(W)], macrolide [erm(B)], methicillin (mecA and mecC), copper (copB, pcoA, pcoD, and tcrB) and zinc (czrC) resistance genes, and three bacterial species (E. coli, Enterococcus spp. and Staphylococcus aureus). The total bacterial population and total abundance of the seven tet genes significantly increased in the three manure types after digestion. Concentration of tet(M) was strongly correlated with that of erm(B) and enterococci. As concentration of tetracyclines declined during anaerobic digestion, that of four tet genes (A, B, Q, and W) and 16S rRNA increased, that of tet(M) decreased, and that of tet(G) and tet(O) did not change. Concentrations of copB and pcoA did not change; while that of pcoD did not change in the PL, it increased in the SM and CM. While the concentration of enterococci remained unchanged in CM, it significantly increased in the PL and SM. Concentrations of tcrB significantly increased in the three manure types. While concentrations of S. aureus significantly increased in the CM and PL, that of SM was not affected. Concentrations of mecC significantly increased in all manure types after digestion; while mecA concentrations did not change in the SM, they significantly increased in CM and PL. While concentration of czrC remained low in the CM, it increased in the PL but declined in the SM. In conclusion, while mesophilic anaerobic digestion of animal manure decreased concentration of tetracyclines, it increased the concentrations of total bacteria, tet genes, E. coli, enterococci and S. aureus and methicillin resistance genes. It did not have any effect on concentrations of heavy metals; concentrations of heavy metal resistance genes either increased or remained unaffected depending on the animal species. This study showed the need for post-digestion treatments of animal manure to remove bacteria, antibiotic resistance genes, heavy metals and their resistance genes.

Anaerobic digestion of livestock and poultry manures spiked with tetracycline antibiotics.

We investigated the anaerobic degradation of tetracycline antibiotics (tetracycline [TC], oxytetracycline [OTC] and chlortetracycline [CTC]) in swine, cattle, and poultry manures. The manures were anaerobically digested inside polyvinyl chloride batch reactors for 64 days at room temperature. The degradation rate constants and half-lives of the parent tetracyclines were determined following first-order kinetics. For CTC the fastest degradation rate was observed in swine manure (k = 0.016 ± 0.001 d-1; half-life = 42.8 days), while the slowest degradation rate was observed in poultry litter (k = 0.0043 ± 0.001 d-1; half-life = 161 days). The half-lives of OTC ranged between 88.9 (cattle manure) and 99.0 days (poultry litter), while TC persisted the longest of the tetracycline antibiotics studied with half-lives ranging from 92.4 days (cattle manure) to 330 days (swine manure). In general, the tetracyclines were found to degrade faster in cattle manure, which had the lowest concentrations of organic matter and metals as compared to swine and poultry manures. Our results demonstrate that tetracycline antibiotics persist in the animal manure after anaerobic digestion, which can potentially lead to emergence and persistence of antibiotic resistant bacteria in the environment when anaerobic digestion byproducts are land applied for crop production.

Bis(imino)pyridine iron complexes for catalytic carbene transfer reactions.

The bis(imino)pyridine iron complex, for the first time, is developed as an effective metal carbene catalyst for carbene transfer reactions of donor-acceptor diazo compounds. Its broad catalytic capability is demonstrated by a range of metal carbene reactions, from cyclopropanation, cyclopropenation, epoxidation, and Doyle-Kirmse reaction to O-H insertion, N-H insertion, and C-H insertion reactions. The asymmetric cyclopropanation of styrene and methyl phenyldiazoacetate was successfully achieved by the new chiral bis(imino)pyridine iron catalyst, which delivers a new gateway for the development of chiral iron catalysis for metal carbene reactions.

Abundances of Tetracycline Resistance Genes and Tetracycline Antibiotics during Anaerobic Digestion of Swine Waste.

The impact of anaerobic digestion of animal waste on the persistence of antibiotic resistance genes (ARGs) and antibiotics is not widely studied. Two identical, 800-L digesters seeded with swine slurry were followed up to 100 d in three separate trials. The trials received varying amounts of antibiotic-free corn ( L.) mixed with water to maintain the digestion process. Biogas production, seven tetracycline resistance () genes, and three tetracyclines and their transformation products were measured. Biogas production proportionally increased as the feeding loads increased between trials. In Trial 1, log gene copies showed small but statistically significant ( < 0.01) increases during digestion. In Trial 2, anaerobic digestion did not have a significant ( > 0.05) effect except for significant reductions in B ( < 0.0001) and G ( = 0.0335) log gene copies. In Trial 3, which received the highest amount of corn mix, log copies of the 16S ribosomal RNA and the genes significantly ( < 0.0001) reduced over time during digestion. Up to 36 µg L tetracycline, 112 µg L chlortetracycline, 11.9 mg L isochlortetracycline, and 30 µg L 4-epitetracycline were detected both in the liquid and solid digestates. Results of this study revealed that although anaerobic digestion of swine waste can produce useful biogas, it does not result in complete removal of bacteria, ARGs, and antibiotics regardless of differences in the feeding loads between trials. Further effluent and sludge treatments are required prior to their downstream use in crop production to minimize emergence and environmental dissemination of antimicrobial-resistant bacteria through animal manure.

One-step synthesis of NaLu80-xGdxF4:Yb183+/Er23+(Tm3+) upconversion nanoparticles for in vitro cell imaging.

Upconversion nanoparticles (UCNPs) possess a unique type of photoluminescence (PL) in which lower-energy excitation is converted into higher-energy emission via multi-photon absorption processes. In this work, we have used a facile one-step hydrothermal method promoted water solubility to synthesis NaLuGdF4:Yb3+/Er3+(Tm3+) UCNPs coated with malonic acid (MA). Scanning electron microscopy images and X-ray diffraction patterns reveal sphere-shaped UCNPs with an average size of ~80nm crystallized in the cubic NaLuF4 structure. The characteristic vibrations of cubic UCNPs have been taken into account by using Fourier-transform infrared spectroscopy. Based on PL studies, we have determined an optimal concentration of Gd3+ doping. The dependence of upconversion PL intensity on Gd3+ concentration is discussed via the results of magnetization measurements, which is related to the coupling/uncoupling of Gd3+ ions. Particularly, our study reveals that carboxyl-functionalized NaLuGdF4:Yb3+/Er3+(Tm3+) UCNPs have a relatively high cell viability with HeLa cells.

Effect of xanthan/enzyme-modified guar gum mixtures on the stability of whey protein isolate stabilized fish oil-in-water emulsions.

The effect of xanthan gum (XG) and enzyme-modified guar (EMG) gum mixtures on the physicochemical properties and oxidative stability of 2wt% whey protein isolate (WPI) stabilized oil-in-water (O/W) emulsions containing 20%v/v fish oil was investigated. EMG was obtained by hydrolyzing native guar gum using α-galactosidase enzyme. At higher gum concentrations (0.2 and 0.3wt%), the viscosity of the emulsions containing XG/EMG gum mixtures was significantly higher (P<0.05) of all emulsions. Increasing concentrations (0-0.3wt%) of XG/EMG gum mixtures did not affect the droplet size of emulsions. Microstructure images revealed decreased flocculation at higher concentrations. Primary and secondary lipid oxidation measurements indicated a slower rate of oxidation in emulsions containing XG/EMG gum mixtures, compared to XG, guar (GG), and XG/GG gum mixtures. These results indicate that XG/EMG gum mixtures can be used in O/W emulsions to increase physical and oxidative stabilities of polyunsaturated fatty acids in foods.

Efficient and inexpensive method for purification of heparin binding proteins.

Heparin binding (HB) proteins mediate a wide range of important cellular processes, which makes this class of proteins biopharmaceutically important. Engineering HB proteins may bring many advantages, but it necessitates cost effective and efficient purification methodologies compared to currently available methods. One of the most important classes of HB proteins are fibroblast growth factors (FGFs) and their receptors (FGFRs). In this study, we report an efficient off-column purification of FGF-1 from soluble fractions and purification of the D2 domain of FGFR from insoluble inclusion bodies, using a weak Amberlite cation (IRC) exchanger. FGF-1 and the D2 domain have been expressed in Escherichia coli and purified to homogeneity using IRC resin. This approach is an alternative to conventional affinity column chromatography, which exhibits several disadvantages, including time-consuming experimental procedures for purification and regeneration and results in the expensive production of recombinant proteins. Results of the heparin binding chromatography and steady state fluorescence experiments show that the FGF-1 and the D2 are in a native conformation. The findings of this study will not only aid an in-depth investigation of this class of proteins but will also provide avenues for inexpensive and efficient purification of other important biological macromolecules.

Human ancient and extant mtDNA from the Gambier Islands (French polynesia): evidence for an early Melanesian maternal contribution and new perspectives into the settlement of easternmost Polynesia.

Molecular anthropology has been widely used to infer the origin and processes of the colonization of Polynesia. However, there are still a lack of representative geographical studies of Eastern Polynesia and unchallenged genetic data about ancient Polynesian people. The absence of both of these elements prevents an accurate description of the demographic processes of internal dispersion within the Polynesian triangle. This study provides a twofold analysis of ancient and modern mtDNA in the eastern part of French Polynesia: the Gambier Islands. The paleogenetic analyses conducted on burials of the Temoe Atoll (14(th) -17(th) centuries) represent the first fully authenticated ancient human sequences from Polynesia. The identification of the "Melanesian" Q1 mtDNA lineage in ancient human remains substantiates the Near Oceanic contribution to the early gene pool of this region. Modern samples originate from Mangareva Island. Genealogical investigations enable us to reliably identify the conservation of the Melanesian component in Easternmost Polynesia, despite recent European colonization. Finally, the identification of rare mutations in sequences belonging to haplogroup B4a1a1a provides new perspectives to the debate on the internal peopling of the Polynesian region. Altogether, the results laid out in our study put the emphasis on the necessity of controlled sampling when discussing the internal settlement of Polynesia.

Dihexadecyldimethylammonium hydroxide admicelles on silica for the preconcentration of selected phenols.

Admicelle based extractions, where sorbents used are prepared by immobilizing charged surfactants in a bilayer arrangement onto a silica or aluminum oxide surface, have been used for preconcentrating a wide variety of analytes. These analytes have a certain degree of hydrophobicity interacting with the alkyl chains of the surfactant or they are counter-charged interacting electrostatically with the charged polar group of the surfactant. Weakly hydrophobic molecules are more challenging to efficiently extract onto this type of medium. Presented is an admicelle extraction procedure for extracting weak acid phenols. An acid-base reaction takes place between modified surfactants containing hydroxide counter ions and weak acid phenols. The result of this reaction is the production of phenolate ions that remain counter to the cationic surfactant. The acid-base reaction together with the fluid nature of the surfactant phase protects the phenolate ions from being removed by counter ions in natural solutions. High extraction efficiencies result.

Investigation of a variety of cationic surfactants attached to cation-exchange silica for hydrophobicity optimization in admicellar solid-phase extraction for high-performance liquid and gas chromatography.

A series of cationic surfactants were attached to cation-exchange silica that included silica modified with sulfopropyl groups and unmodified silica to create hydrophobic solid-phase extraction sorbents. Various chain lengths and chain numbers of amine, ammonium and pyridinium-based cationic surfactants were investigated to reach sufficient sorbent hydrophobicity to capture US Environmental Protection Agency (EPA) priority polycyclic aromatic hydrocarbons (PAHs). Of the tested surfactant/silica combinations, dihexadecyldimethylammonium cations attached to unmodified silica resulted in the sorbent having the greatest hydrophobicity. This sorbent provided strong hydrophobic attraction of PAHs and also efficient elution because the PAHs were removed together with the surfactant using a very mild 5% acetic acid in methanol rinse solution. This admicellar solid-phase extraction procedure was applied for the determination of these PAHs for both high-performance liquid and gas chromatography. The detection limits of these PAHs were below the EPA's maximum contaminant level of 0.2 microg/L.

Determination of polyaromatic hydrocarbons in river water using a sorbent consisting of removable octadecyltrimethylammonium ions attached to cation exchange silica in conjunction with commercial C18 silica.

An application that highlights the usefulness of a solid phase extraction sorbent having a removable surfactant "stationary phase" is introduced. Polyaromatic hydrocarbons (PAHs) efficiently trap on commercially available non-polar sorbents (i.e., C(18) silica). However, solvents that are necessary to break strong hydrophobic interactions between the analyte and sorbent are harmful and incompatible for direct introduction into a reversed phase liquid chromatographic setup. In the presented approach, the entire "stationary phase"-analyte association is removed, resulting in very efficient elutions with a final extract that is mild and reversed phase liquid chromatographic compatible. Commercial C(18) silica was placed adjacent to this sorbent to provide more efficient trapping of less hydrophobic PAHs. PAHs were preconcentrated from river water and were determined using fluorescence detection coupled to HPLC. Detection limits for all PAHs examined were in the sub [micro sign]g L(-1) level.

A solid-phase microextraction device for the analysis of electrochemical reaction products by gas chromatography/mass spectrometry.

Presented is a solid-phase microextraction syringe-electrode assembly that may be used to identify electrode reaction products. After an electrochemical experiment, the electrode within this syringe-electrode assembly can be introduced into the injection port of a gas chromatograph. Electrochemical reaction products can be analyzed, provided they adhere to the electrode surface and are amenable to gas chromatographic/mass spectrometric analysis. We highlight the potential usefulness of this device using well-known electrochemical reaction of quinones.