Selection of aquatic microbiota exposed to the herbicides flufenacet and metazachlor

Herbicides are important, ubiquitous environmental contaminants, but little is known about their interaction with bacterial aquatic communities. Here, we sampled a protected natural freshwater habitat and characterised its microbiome in interaction with herbicides. We evolved the freshwater microbiomes in a microcosm assay of exposure (28 days) to flufenacet and metazachlor at environmental concentrations of 0.5, 5 and 50 μg L⁻¹. Inhibitory effects of herbicides were exemplarily assessed in cultured bacteria from the same pond (Pseudomonas alcaligenes, Paenibacillus amylolyticus and Microbacterium hominis). Findings were compared to long-term concentrations as provided by local authorities. Here, environmental concentrations reached up to 11 μg L⁻¹ (flufenacet) and 76 μg L⁻¹ (metazachlor). Bacteria were inhibited at minimum inhibitory concentrations far above these values; however, concentrations of 50 μg L⁻¹ of flufenacet resulted in measurable growth impairment. While most herbicide-exposed microcosm assays did not differ from controls, Acidobacteria were selected at high environmental concentrations of herbicides. Alpha-diversity (e.g., taxonomic richness on phylum level) was reduced when aquatic microbiomes were exposed to 50 μg metazachlor or flufenacet. One environmental strain of P. alcaligenes showed resistance to high concentrations of flufenacet (50 g L⁻¹). In total, this study reveals that ecologic imbalance due to herbicide use significantly impacts aquatic microbiomes.     

Clinical Evaluation of Adriamycin,a New Antitumour Antibiotic

Adriamycin, a new antitumour antibiotic of the anthracycline group with a structural formula very similar to daunorubicin, has proved to have potent tumour-growth-inhibiting properties, and to be particularly effective in childhood malignancies. Though adriamycin produces a higher percentage of side-effects than daunorubicin—namely, stomatitis and alopecia—a lower dosage may be used for therapy.     

A Genome-wide RNAi Screen Reveals a Trio-Regulated Rho GTPase Circuitry Transducing Mitogenic Signals Initiated by G Protein-Coupled Receptors

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Highlights? Human cancers harbor frequent mutations in Gq-linked GPCRs and Gα_q subunits ? A genome-wide RNAi screen revealed that Trio is essential for activating AP-1 via Gα_q ? A network of Trio-regulated Rho GTPases and MAPKs links Gq to the nucleus ? A hard-wired Gq-Trio signaling axis promotes the growth of many human malignancies     

Two novel dermonecrotic toxins LiRecDT4 and LiRecDT5 from brown spider (Loxosceles intermedia) venom: from cloning to functional characterization

Loxoscelism (the condition produced by the bite of brown spiders) has been reported worldwide, but especially in warmer regions. Clinical manifestations include skin necrosis with gravitational spreading while systemic loxoscelism may include renal failure, hemolysis and thrombocytopenia. The venom contains several toxins, of which the best biochemically and biologically studied is the dermonecrotic toxin, a phospholipase-D. Purified toxin induces cutaneous and systemic loxoscelism, especially necrotic lesions, hematological disturbances and renal failure. Herein, we describe cloning, heterologous expression and purification of two novel dermonecrotic toxins: LiRecDT4 and LiRecDT5. The recombinant proteins stably expressed in Escherichia coli cells were purified from culture supernatants in a single step using Ni(2+)-chelating chromatography producing soluble proteins of 34 kDa (LiRecDT4) and 37 kDa (LiRecDT5). Circular dichroism analysis evidenced correctly folding for toxins but differences in secondary structures. Both proteins were recognized by whole venom serum antibodies and by a specific antibody to dermonecrotic toxin. Also, recombinant toxins with phospholipase activity induced experimental skin lesions and caused a massive inflammatory response in rabbit skin dermis. Nevertheless, toxins displayed different effects upon platelet aggregation, increase in vascular permeability and not caused death in mice. These characteristics in combination with functional studies illustrates that a family of dermonecrotic toxins exists, and includes two novel members that are useful for future structural and functional studies. They will also be useful in biotechnological ends, for example, as inflammatory and platelet aggregating studies, as antigens for serum therapy source and for lipids biochemical research.     

Multisensory mechanisms in temporo-parietal cortex support self-location and first-person perspective

Self-consciousness has mostly been approached by philosophical enquiry and not by empirical neuroscientific study, leading to an overabundance of diverging theories and an absence of data-driven theories. Using robotic technology, we achieved specific bodily conflicts and induced predictable changes in a fundamental aspect of self-consciousness by altering where healthy subjects experienced themselves to be (self-location). Functional magnetic resonance imaging revealed that temporo-parietal junction (TPJ) activity reflected experimental changes in self-location that also depended on the first-person perspective due to visuo-tactile and visuo-vestibular conflicts. Moreover, in a large lesion analysis study of neurological patients with a well-defined state of abnormal self-location, brain damage was also localized at TPJ, providing causal evidence that TPJ encodes self-location. Our findings reveal that multisensory integration at the TPJ reflects one of the most fundamental subjective feelings of humans: the feeling of being an entity localized at a position in space and perceiving the world from this position and perspective.     

Fix your eyes in the space you could reach: neurons in the macaque medial parietal cortex prefer gaze positions in peripersonal space

Interacting in the peripersonal space requires coordinated arm and eye movements to visual targets in depth. In primates, the medial posterior parietal cortex (PPC) represents a crucial node in the process of visual-to-motor signal transformations. The medial PPC area V6A is a key region engaged in the control of these processes because it jointly processes visual information, eye position and arm movement related signals. However, to date, there is no evidence in the medial PPC of spatial encoding in three dimensions. Here, using single neuron recordings in behaving macaques, we studied the neural signals related to binocular eye position in a task that required the monkeys to perform saccades and fixate targets at different locations in peripersonal and extrapersonal space. A significant proportion of neurons were modulated by both gaze direction and depth, i.e., by the location of the foveated target in 3D space. The population activity of these neurons displayed a strong preference for peripersonal space in a time interval around the saccade that preceded fixation and during fixation as well. This preference for targets within reaching distance during both target capturing and fixation suggests that binocular eye position signals are implemented functionally in V6A to support its role in reaching and grasping.     

CRM197 (nontoxic diphtheria toxin): effects on advanced cancer patients

Purpose: Many years ago, diphtheria toxin (DT) showed antitumor activity in mice and in humans, but it was unclear whether this depended on the toxicity of the molecule only or on its strong inflammatory-immunological property as well. To deal with this open question, we planned to treat a group of cancer patients with cross-reacting material 197 (CRM197). CRM197 is a nontoxic mutant of DT that shares the immunological properties of the native molecule and its ability to bind to heparin-binding epidermal growth factor (HB-EGF), the specific cell-membrane receptor for DT that is often overexpressed in cancer. Methods: 25 outpatients with various advanced tumors who were refractory to standard therapies (23 subjects) or had refused, in whole or in part, conventional therapies (2 subjects) were treated with CRM197 injected subcutaneously in the abdominal wall, on alternate days, for 6 days. Three different dosages (1.7, 2.6, or 3.5 mg/day) were used according to the patients degree of immunological reactivity to DT/CRM197 (none, moderate, or high). Results: After the first administration of CRM197, a significant increase in the number of circulating neutrophils and in the serum level of TNF- was detected. Toxicities were minimal. Only patients with delayed-type hypersensitivity to DT/CRM197 had irritating skin reactions in the injection sites and a flu-like syndrome with fever. Pharmacokinetics showed a mean peak concentration (12.7 ng/ml) 12 h after the first injection and a mean half-life of 18.1 h. There were two complete and one partial responses (metastatic breast carcinoma, neuroblastoma, and metastatic breast carcinoma) lasting 4, 45+, and 15 months, respectively. Six cases of stable disease, lasting from 1 to 15 months, were also recorded. Conclusions: CRM197 injected subcutaneously elicited an inflammatory-immunological reaction, caused tolerable toxicities, was absorbed to a good extent into the circulatory system, and exerted some degree of biological antitumor activity. A possible role of neutrophils and TNF- in the mode of action of the molecule is hypothesized.     

μ3-S bonding mode in H2M3(CO)9S clusters of Ru and Os. An UVPES and theoretical study

The electronic structure of H₂M₃(CO)₉S clusters (M = Ru, Os) is discussed on the basis of their He I and He II excited gas-phase photoelectron spectra and on the basis of CNDO quantum mechanical calculations. The PE data clearly demonstrate the cleavage of two direct MM interactions by operation of the bridging hydrides, giving rise to three-center two-electron MHM levels. The μ₃-S bonding mode has been described in detail and compared with previous results on related μ₃-CY cluster derivatives. The CNDO results on Ru₃(CO)₉S⁼, HRu₃(CO)₉S^? and H₂Ru₃(CO)₉S indicate that the μ₃-S—cluster interaction is mostly independent of the presence of the bridging hydrides.