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271.
Meijaard E Buchori D Hadiprakarsa Y Utami-Atmoko SS Nurcahyo A Tjiu A Prasetyo D Nardiyono Christie L Ancrenaz M Abadi F Antoni IN Armayadi D Dinato A Ella Gumelar P Indrawan TP Kussaritano Munajat C Priyono CW Purwanto Y Puspitasari D Putra MS Rahmat A Ramadani H Sammy J Siswanto D Syamsuri M Andayani N Wu H Wells JA Mengersen K 《PloS one》2011,6(11):e27491
Human-orangutan conflict and hunting are thought to pose a serious threat to orangutan existence in Kalimantan, the Indonesian part of Borneo. No data existed prior to the present study to substantiate these threats. We investigated the rates, spatial distribution and causes of conflict and hunting through an interview-based survey in the orangutan's range in Kalimantan, Indonesia. Between April 2008 and September 2009, we interviewed 6983 respondents in 687 villages to obtain socio-economic information, assess knowledge of local wildlife in general and orangutan encounters specifically, and to query respondents about their knowledge on orangutan conflicts and killing, and relevant laws. This survey revealed estimated killing rates of between 750 and 1800 animals killed in the last year, and between 1950 and 3100 animals killed per year on average within the lifetime of the survey respondents. These killing rates are higher than previously thought and are high enough to pose a serious threat to the continued existence of orangutans in Kalimantan. Importantly, the study contributes to our understanding of the spatial variation in threats, and the underlying causes of those threats, which can be used to facilitate the development of targeted conservation management. 相似文献
272.
Secretor genotype (FUT2 gene) is strongly associated with the composition of Bifidobacteria in the human intestine 总被引:1,自引:0,他引:1
Wacklin P Mäkivuokko H Alakulppi N Nikkilä J Tenkanen H Räbinä J Partanen J Aranko K Mättö J 《PloS one》2011,6(5):e20113
Intestinal microbiota plays an important role in human health, and its composition is determined by several factors, such as diet and host genotype. However, thus far it has remained unknown which host genes are determinants for the microbiota composition. We studied the diversity and abundance of dominant bacteria and bifidobacteria from the faecal samples of 71 healthy individuals. In this cohort, 14 were non-secretor individuals and the remainders were secretors. The secretor status is defined by the expression of the ABH and Lewis histo-blood group antigens in the intestinal mucus and other secretions. It is determined by fucosyltransferase 2 enzyme, encoded by the FUT2 gene. Non-functional enzyme resulting from a nonsense mutation in the FUT2 gene leads to the non-secretor phenotype. PCR-DGGE and qPCR methods were applied for the intestinal microbiota analysis. Principal component analysis of bifidobacterial DGGE profiles showed that the samples of non-secretor individuals formed a separate cluster within the secretor samples. Moreover, bifidobacterial diversity (p<0.0001), richness (p<0.0003), and abundance (p<0.05) were significantly reduced in the samples from the non-secretor individuals as compared with those from the secretor individuals. The non-secretor individuals lacked, or were rarely colonized by, several genotypes related to B. bifidum, B. adolescentis and B. catenulatum/pseudocatenulatum. In contrast to bifidobacteria, several bacterial genotypes were more common and the richness (p<0.04) of dominant bacteria as detected by PCR-DGGE was higher in the non-secretor individuals than in the secretor individuals. We showed that the diversity and composition of the human bifidobacterial population is strongly associated with the histo-blood group ABH secretor/non-secretor status, which consequently appears to be one of the host genetic determinants for the composition of the intestinal microbiota. This association can be explained by the difference between the secretor and non-secretor individuals in their expression of ABH and Lewis glycan epitopes in the mucosa. 相似文献
273.
Partinen M Saarenpää-Heikkilä O Ilveskoski I Hublin C Linna M Olsén P Nokelainen P Alén R Wallden T Espo M Rusanen H Olme J Sätilä H Arikka H Kaipainen P Julkunen I Kirjavainen T 《PloS one》2012,7(3):e33723
Background
Narcolepsy is a rare neurological sleep disorder especially in children who are younger than 10 years. In the beginning of 2010, an exceptionally large number of Finnish children suffered from an abrupt onset of excessive daytime sleepiness (EDS) and cataplexy. Therefore, we carried out a systematic analysis of the incidence of narcolepsy in Finland between the years 2002–2010.Methods
All Finnish hospitals and sleep clinics were contacted to find out the incidence of narcolepsy in 2010. The national hospital discharge register from 2002 to 2009 was used as a reference.Findings
Altogether 335 cases (all ages) of narcolepsy were diagnosed in Finland during 2002–2009 giving an annual incidence of 0.79 per 100 000 inhabitants (95% confidence interval 0.62–0.96). The average annual incidence among subjects under 17 years of age was 0.31 (0.12–0.51) per 100 000 inhabitants. In 2010, 54 children under age 17 were diagnosed with narcolepsy (5.3/100 000; 17-fold increase). Among adults ≥20 years of age the incidence rate in 2010 was 0.87/100 000, which equals that in 2002–2009. Thirty-four of the 54 children were HLA-typed, and they were all positive for narcolepsy risk allele DQB1*0602/DRB1*15. 50/54 children had received Pandemrix vaccination 0 to 242 days (median 42) before onset. All 50 had EDS with abnormal multiple sleep latency test (sleep latency <8 min and ≥2 sleep onset REM periods). The symptoms started abruptly. Forty-seven (94%) had cataplexy, which started at the same time or soon after the onset of EDS. Psychiatric symptoms were common. Otherwise the clinical picture was similar to that described in childhood narcolepsy.Interpretation
A sudden increase in the incidence of abrupt childhood narcolepsy was observed in Finland in 2010. We consider it likely that Pandemrix vaccination contributed, perhaps together with other environmental factors, to this increase in genetically susceptible children. 相似文献274.
275.
Shazia N. Aslam Graham J. C. Underwood Hermanni Kaartokallio Louiza Norman Riitta Autio Michael Fischer Harri Kuosa Gerhard S. Dieckmann David N. Thomas 《Polar Biology》2012,35(5):661-676
Extracellular polymeric substances (EPS) are known to help microorganisms to survive under extreme conditions in sea ice.
High concentrations of EPS are reported in sea ice from both poles; however, production and dynamics of EPS during sea ice
formation have been little studied to date. This investigation followed the production and partitioning of existing and newly
formed dissolved organic matter (DOM) including dissolved carbohydrates (dCHO), dissolved uronic acids (dUA) and dissolved
EPS (dEPS), along with bacterial abundances during early stages of ice formation. Sea ice was formed from North Sea water
with (A) ambient DOM (NSW) and (B) with additional algal-derived DOM (ADOM) in a 6d experiment in replicated mesocosms. In
ADOM seawater, total bacterial numbers (TBN) increased throughout the experiment, whereas bacterial growth occurred for 5d
only in the NSW seawater. TBN progressively decreased within developing sea ice but with a 2-fold greater decline in NSW compared
to ADOM ice. There were significant increases in the concentrations of dCHO in ice. Percentage contribution of dEPS was highest
(63%) in the colder, uppermost parts in ADOM ice suggesting the development of a cold-adapted community, producing dEPS possibly
for cryo-protection and/or protection from high salinity brines. We conclude that in the early stages of ice formation, allochthonous
organic matter was incorporated from parent seawater into sea ice and that once ice formation had established, there were
significant changes in the concentrations and composition of dissolved organic carbon pool, resulting mainly from the production
of autochthonous DOM by the bacteria. 相似文献
276.
Lindberg HK Falck GC Catalán J Koivisto AJ Suhonen S Järventaus H Rossi EM Nykäsenoja H Peltonen Y Moreno C Alenius H Tuomi T Savolainen KM Norppa H 《Mutation research》2012,745(1-2):58-64
In vitro studies have suggested that nanosized titanium dioxide (TiO(2)) is genotoxic. The significance of these findings with respect to in vivo effects is unclear, as few in vivo studies on TiO(2) genotoxicity exist. Recently, nanosized TiO(2) administered in drinking water was reported to increase, e.g., micronuclei (MN) in peripheral blood polychromatic erythrocytes (PCEs) and DNA damage in leukocytes. Induction of micronuclei in mouse PCEs was earlier also described for pigment-grade TiO(2) administered intraperitoneally. The apparent systemic genotoxic effects have been suggested to reflect secondary genotoxicity of TiO(2) due to inflammation. However, a recent study suggested that induction of DNA damage in mouse bronchoalveolar lavage (BAL) cells after intratracheal instillation of nanosized or fine TiO(2) is independent of inflammation. We examined here, if inhalation of freshly generated nanosized TiO(2) (74% anatase, 26% brookite; 5 days, 4 h/day) at 0.8, 7.2, and (the highest concentration allowing stable aerosol production) 28.5 mg/m(3) could induce genotoxic effects in C57BL/6J mice locally in the lungs or systematically in peripheral PCEs. DNA damage was assessed by the comet assay in lung epithelial alveolar type II and Clara cells sampled immediately following the exposure. MN were analyzed by acridine orange staining in blood PCEs collected 48 h after the last exposure. A dose-dependent deposition of Ti in lung tissue was seen. Although the highest exposure level produced a clear increase in neutrophils in BAL fluid, indicating an inflammatory effect, no significant effect on the level of DNA damage in lung epithelial cells or micronuclei in PCEs was observed, suggesting no genotoxic effects by the 5-day inhalation exposure to nanosized TiO(2) anatase. Our inhalation exposure resulted in much lower systemic TiO(2) doses than the previous oral and intraperitoneal treatments, and lung epithelial cells probably received considerably less TiO(2) than BAL cells in the earlier intratracheal study. 相似文献
277.
A Kiviniemi J Mäkelä J Mäkilä T Saanijoki H Liljenbäck P Poijärvi-Virta H Lönnberg T Laitala-Leinonen A Roivainen P Virta 《Bioconjugate chemistry》2012,23(9):1981-1988
Esterified precursors of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA; 18) and 1,4,7-triazacyclononane-1,4,7-trisacetic acid (NOTA; 17,19) ligands bearing a dimethoxytritylated hydroxyl side arm were prepared and immobilized via an ester linkage to long chain alkyl amine derivatized controlled pore glass (LCAA-CPG). Oligonucleotide chains were then assembled on the hydroxyl function and conjugates were released and deprotected by a two-step cleavage with aqueous alkali and ammonia. The 3'-DOTA and 3'-NOTA conjugated oligonucleotides were converted to (68)Ga chelates by a brief treatment with [(68)Ga]Cl(3) at elevated temperature. Applicability of the conjugates for in vivo imaging with positron emission tomography (PET) was verified. 相似文献
278.
Noponen V Belt H Lahtinen M Valkonen A Salo H Ulrichová J Galandáková A Sievänen E 《Steroids》2012,77(3):193-203
Design, synthesis, and characterization of six novel bile acid-cysteamine conjugates together with investigation of their structural studies, gelation properties, and preliminary toxicity evaluation, are reported. Solid state properties of selected compounds were studied by means of X-ray diffraction and (13)C CPMAS NMR spectroscopy. N-(2-thioethyl)-3α,7α,12α-trihydroxy-5β-cholan-24-amide was shown to exhibit (pseudo)polymorphism, and a single crystal structure of its non-stoichiometric hydrate is reported herein. Cholyl and dehydrocholyl derivatives bearing three functionalities in their steroidal backbone were shown to undergo self-assembly leading to gelation in certain organic solvents. Preliminary morphology studies of the formed gels by scanning electron microscopy (SEM) were performed. The standard model mouse fibroblast cell line together with the MTT and NR tests were utilized for evaluating the toxicity of the prepared compounds. Lithocholyl, ursodeoxycholyl, and dehydrocholyl derivatives turned out to be relatively non-toxic in the conditions studied. 相似文献
279.
KV Ahonen MK Lahtinen MS Löfman AM Kiesilä AM Valkonen EI Sievänen Nonappa ET Kolehmainen 《Steroids》2012,77(11):1141-1151
Synthesis and solid-state structural characterization of five bile acid amides of 4-aminopyridine (4-AP) are reported. Systematic crystallization experiments revealed a number of structural modifications and/or solvate/hydrate systems for these conjugates. Particularly, cholic acid conjugate exhibited five distinct structure modifications, including one anhydrous form, mono- and dihydrates, as well as ethanol and 2-butanol solvates. The obtained crystal forms were examined extensively with various analytical methods, including solid-state NMR, Raman, and IR spectroscopies, powder and single crystal X-ray diffraction methods, thermogravimetry, and differential scanning calorimetry. After releasing their crystal solvent molecules, the resulted non-solvated structure forms showed 50-75°C higher melting points than corresponding bile acids, and thermal degradation occurred for all conjugates at about 300-330°C. Moreover, the single crystal X-ray structure of the ursodeoxycholic acid-4-aminopyridine conjugate is reported. 相似文献
280.
The main aim of this study was to investigate occupational exposure to electric fields, and current densities and contact currents associated with tasks at air-insulated 110 kV substations and analyze if the action value of EU Directive 2004/40/EC was exceeded. Four workers volunteered to simulate the following tasks: Task (A) maintenance of an operating device of a disconnector at ground or floor level, Task (B) maintenance of an operating device of a circuit breaker at ground or floor level, Task (C) breaker head maintenance from a man hoist, and Task (D) maintenance of an operating device of a circuit breaker from a service platform. The highest maximum average current density in the neck was 1.8 mA/m(2) (calculated internal electric field 9.0-18.0 mV/m) and the highest contact current was 79.4 μA. All measured values at substations were lower than the limit value (10 mA/m(2)) of the EU Directive 2004/40/EC and the 2010 basic restrictions (0.1 and 0.8 V/m for central nervous system tissues of the head, and all tissues of the head and body, respectively) of the International Commission on Non-Ionizing Radiation Protection (ICNIRP). 相似文献