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121.
Wildlife crime such as illegal hunting of elephants and rhinos is currently one of the major issues in conservation. In order to combat poaching, law enforcement is essential. Here, we reviewed wildlife cases from the Northern Zone Anti‐Poaching Unit, Arusha, Tanzania (APU‐Arusha), focusing on the types of wildlife offence committed, prosecution outcomes and the sentences awarded to the offenders who were found guilty by the courts. Eighty‐two registered cases were thoroughly reviewed. The majority of wildlife offences committed were unlawful possession of, and failure to report, government trophies. It was found that only 16% of the accused were found guilty, 6% were acquitted, 30% of the charges were withdrawn, and 48% of the cases were discharged by the director of public prosecution (DPP) or magistrate. The poor conviction rate was attributed to weak evidence, failure of the prosecution to prove cases beyond reasonable doubt, lack of cooperation between the zonal game office and the DPP, and in some cases, the accused jumped their bails. Understanding the factors which allow individuals to continue to engage in poaching and the factors that promote the practice of good governance is vital in trying to stop wildlife crimes.  相似文献   
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Increasing evidence indicates that the Trypanosoma brucei flagellum (synonymous with cilium) plays important roles in host-parasite interactions. Several studies have identified virulence factors and signaling proteins in the flagellar membrane of bloodstream-stage T. brucei, but less is known about flagellar membrane proteins in procyclic, insect-stage parasites. Here we report on the identification of several receptor-type flagellar adenylate cyclases (ACs) that are specifically upregulated in procyclic T. brucei parasites. Identification of insect stage-specific ACs is novel, as previously studied ACs were constitutively expressed or confined to bloodstream-stage parasites. We show that procyclic stage-specific ACs are glycosylated, surface-exposed proteins that dimerize and possess catalytic activity. We used gene-specific tags to examine the distribution of individual AC isoforms. All ACs examined localized to the flagellum. Notably, however, while some ACs were distributed along the length of the flagellum, others specifically localized to the flagellum tip. These are the first transmembrane domain proteins to be localized specifically at the flagellum tip in T. brucei, emphasizing that the flagellum membrane is organized into specific subdomains. Deletion analysis reveals that C-terminal sequences are critical for targeting ACs to the flagellum, and sequence comparisons suggest that differential subflagellar localization might be specified by isoform-specific C termini. Our combined results suggest insect stage-specific roles for a subset of flagellar adenylate cyclases and support a microdomain model for flagellar cyclic AMP (cAMP) signaling in T. brucei. In this model, cAMP production is compartmentalized through differential localization of individual ACs, thereby allowing diverse cellular responses to be controlled by a common signaling molecule.  相似文献   
124.

Background

Species of Cronobacter are widespread in the environment and are occasional food-borne pathogens associated with serious neonatal diseases, including bacteraemia, meningitis, and necrotising enterocolitis. The genus is composed of seven species: C. sakazakii, C. malonaticus, C. turicensis, C. dublinensis, C. muytjensii, C. universalis, and C. condimenti. Clinical cases are associated with three species, C. malonaticus, C. turicensis and, in particular, with C. sakazakii multilocus sequence type 4. Thus, it is plausible that virulence determinants have evolved in certain lineages.

Methodology/Principal Findings

We generated high quality sequence drafts for eleven Cronobacter genomes representing the seven Cronobacter species, including an ST4 strain of C. sakazakii. Comparative analysis of these genomes together with the two publicly available genomes revealed Cronobacter has over 6,000 genes in one or more strains and over 2,000 genes shared by all Cronobacter. Considerable variation in the presence of traits such as type six secretion systems, metal resistance (tellurite, copper and silver), and adhesins were found. C. sakazakii is unique in the Cronobacter genus in encoding genes enabling the utilization of exogenous sialic acid which may have clinical significance. The C. sakazakii ST4 strain 701 contained additional genes as compared to other C. sakazakii but none of them were known specific virulence-related genes.

Conclusions/Significance

Genome comparison revealed that pair-wise DNA sequence identity varies between 89 and 97% in the seven Cronobacter species, and also suggested various degrees of divergence. Sets of universal core genes and accessory genes unique to each strain were identified. These gene sequences can be used for designing genus/species specific detection assays. Genes encoding adhesins, T6SS, and metal resistance genes as well as prophages are found in only subsets of genomes and have contributed considerably to the variation of genomic content. Differences in gene content likely contribute to differences in the clinical and environmental distribution of species and sequence types.  相似文献   
125.
Four novel thiazole containing ABP688 derivatives were synthesized and evaluated for their binding affinity towards the metabotropic glutamate receptor subtype 5 (mGluR5). (E)-3-((2-(Fluoromethyl)thiazol-4-yl)ethynyl)cyclohex-2-enone O-methyl oxime (FTECMO), the ligand with the highest binding affinity (Ki = 5.5 ± 1.1 nM), was labeled with fluorine-18. [18F]-FTECMO displayed optimal lipophilicity (log DpH7.4 = 1.6 ± 0.2) and high stability in rat and human plasma as well as sufficient stability in rat liver microsomes. In vitro autoradiography with [18F]-FTECMO revealed a heterogeneous and displaceable binding in mGluR5-rich brain regions. PET imaging with [18F]-FTECMO in Wistar rats, however, showed low brain uptake. Uptake of radioactivity into the skull was observed suggesting in vivo defluorination. Thus, although [18F]-FTECMO is an excellent ligand for the detection of mGluR5 in vitro, its in vivo characteristics are not optimal for the imaging of mGluR5 in rats in vivo.  相似文献   
126.
Niederhauser  Pius  Schanz  Ferdinand 《Hydrobiologia》1993,269(1):453-462
The effects of nutrient additions upon the epilithic diatom communities and the algal standing crop were investigated in the oligotrophic, softwater Lake Piccolo Naret, situated in the Swiss alps. Nutrient-diffusing flower pot substrates were filled with either N (0.15 mol NaNO3), P (0.015 mol Na2HPO4) or C (0.15 mol NaHCO3) or combinations of them. Twenty-five pots representing eight treatments were placed into the lake in July 1991 and sampled after 42 days of exposure.On the surfaces of all pots containing P we measured higher algal biomasses as on the control pots. The chlorophyll-a maximum of 12.9 µg cm– 2 was obtained on NPC pots (0.47 µg cm– 2 on control pots). On pots with P, NP or NPC supply high amounts of green algae were detected, also reflected in an increased chl-b/chl-c ratio related to the controls which showed algal communities dominated by diatoms.The diatom communities on the control pots as well as on the pots with N, P and NP had a structure similar to the epilithic community in Lake Piccolo Naret (dominance identity > 58 %). However, the community structures of the diatoms from pots with C addition (C, NC, PC and NPC) differed considerably. This is discussed in view of the cell densities of dominant diatom species. For further comparisons the results of two additional high-mountain lakes are used. By means of a cluster analysis it could be shown that epilithic diatom communities were considerably influenced by C addition, while N and P supply were of minor importance.  相似文献   
127.
In about 20% of patients with rheumatoid arthritis, B and T lymphocytes recruited into the inflamed synovium are organized into complex microstructures, which resemble secondary lymphoid organs. The development of such lymphoid aggregates with germinal centers appears to contribute to the pathogenesis of the disease. Growing evidence indicates that chemokines and their receptors control the recruitment and positioning of leukocytes as well as their organization into node-like lymphoid structures. Here, we comment on recent studies highlighting the importance of chemokines in rheumatoid arthritis, in particular of B-cell-activating chemokine-1 in lymphoid neogenesis in the inflamed synovium.  相似文献   
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