Phylogenetic analysis of human Chlamydia pneumoniae strains reveals a distinct Australian indigenous clade that predates European exploration of the continent

© 2015 Roulis et al. Background: The obligate intracellular bacterium Chlamydia pneumoniae is a common respiratory pathogen, which has been found in a range of hosts including humans, marsupials and amphibians. Whole genome comparisons of human C. pneumoniae have previously highlighted a highly conserved nucleotide sequence, with minor but key polymorphisms and additional coding capacity when human and animal strains are compared. Results: In this study, we sequenced three Australian human C. pneumoniae strains, two of which were isolated from patients in remote indigenous communities, and compared them to all available C. pneumoniae genomes. Our study demonstrated a phylogenetically distinct human C. pneumoniae clade containing the two indigenous Australian strains, with estimates that the most recent common ancestor of these strains predates the arrival of European settlers to Australia. We describe several polymorphisms characteristic to these strains, some of which are similar in sequence to animal C. pneumoniae strains, as well as evidence to suggest that several recombination events have shaped these distinct strains. Conclusions: Our study reveals a greater sequence diversity amongst both human and animal C. pneumoniae strains, and suggests that a wider range of strains may be circulating in the human population than current sampling indicates

Low Secondary Risks for Captive Coyotes from a Sodium Nitrite Toxic Bait for Invasive Wild Pigs

An acute toxic bait is being developed to deliver micro‐encapsulated sodium nitrite (SN) to stimulate severe methemoglobinemia and humane death for invasive wild pigs (Sus scrofa), thereby providing a new tool for reducing their populations. During April 2016, we evaluated sensitivity to SN and outcomes of secondary consumption in the ubiquitous mammalian scavenger, coyote (Canis latrans), to determine secondary risks of consuming carcasses of wild pigs that died from consuming the SN toxic bait. At the National Wildlife Research Center in Fort Collins, Colorado, USA, we first evaluated whether coyotes fed carcasses of domestic pigs killed by consumption of SN bait showed signs of SN intoxication. Second, we conducted chemical analysis of residual SN in the coyotes for evidence of SN passing from pigs to coyotes. Last, we conducted an acute oral toxicity test (LD50) with SN for coyotes by feeding them meatballs containing capsules of SN. We found no evidence that captive coyotes experienced SN intoxication from consuming on carcasses that had been freshly poisoned with SN, despite consuming ¯ x = 1.6 kg of tissues/coyote within 24 hours. None of the captive coyotes consumed digestive tracts or stomach contents from poisoned carcasses, which contained the highest levels of residual SN. Chemical analysis indicated that only ≤34.14 mg/kg of residual SN were passed from the tissues of the pigs into the coyotes, confirming that SN does not bioaccumulate. All coyotes quickly vomited various doses of SN during the LD50 test and fully recovered, suggesting a natural defense against secondary poisoning from SN. Testing with captive coyotes indicates that the risks of secondary poisoning for free‐ranging coyotes are likely low, although field‐testing should be used to confirm

Characterizing human lung tissue microbiota and its relationship to epidemiological and clinical features

Background: The human lung tissue microbiota remains largely uncharacterized, although a number of studies based on airway samples suggest the existence of a viable human lung microbiota. Here we characterized the taxonomic and derived functional profiles of lung microbiota in 165 non-malignant lung tissue samples from cancer patients. Results: We show that the lung microbiota is distinct from the microbial communities in oral, nasal, stool, skin, and vagina, with Proteobacteria as the dominant phylum (60 %). Microbiota taxonomic alpha diversity increases with environmental exposures, such as air particulates, residence in low to high population density areas, and pack-years of tobacco smoking and decreases in subjects with history of chronic bronchitis. Genus Thermus is more abundant in tissue from advanced stage (IIIB, IV) patients, while Legionella is higher in patients who develop metastases. Moreover, the non-malignant lung tissues have higher microbiota alpha diversity than the paired tumors. Conclusions: Our results provide insights into the human lung microbiota composition and function and their link to human lifestyle and clinical outcomes. Studies among subjects without lung cancer are needed to confirm our findings

Effect of synthetic hormones on reproduction in Mastomys natalensis

Rodent pest management traditionally relies on some form of lethal control. Developing effective fertility control for pest rodent species could be a major breakthrough particularly in the context of managing rodent population outbreaks. This laboratory-based study is the first to report on the effects of using fertility compounds on an outbreaking rodent pest species found throughout sub-Saharan Africa. Mastomys natalensis were fed bait containing the synthetic steroid hormones quinestrol and levonorgestrel, both singly and in combination, at three concentrations (10, 50, 100 ppm) for seven days. Consumption of the bait and animal body mass was mostly the same between treatments when analysed by sex, day and treatment. However, a repeated measures ANOVA indicated that quinestrol and quinestrol+levonorgestrel treatments reduced consumption by up to 45%, particularly at the higher concentrations of 50 and 100 ppm. Although there was no clear concentration effect on animal body mass, quinestrol and quinestrol+levonorgestrel lowered body mass by up to 20% compared to the untreated and levonorgestrel treatments. Quinestrol and quinestrol+levonorgestrel reduced the weight of male rat testes, epididymis and seminal vesicles by 60-80%, and sperm concentration and motility were reduced by more than 95%. No weight changes were observed to uterine and ovarian tissue; however, high uterine oedema was observed among all female rats consuming treated bait at 8 days and 40 days from trial start. Trials with mate pairing showed there were significant differences in the pregnancy rate with all treatments when compared to the untreated control group of rodents

The Origin of the Speeches: language evolution through collaborative reinforcement learning.

This project proposes that language evolve through reinforcement learning where agents communicate with each other and provide rewards if communication is successful. The fundamental difference between the learning mechanisms that humans use to communicate with one another and how machines learn to communicate is that the system used by humans presupposes that the adult already knows the meanings associated with the human language. Languages evolve historically to be optimal communication systems where human language learning mechanisms have evolved in order to learn these systems more efficiently. Machines in their learning of natural language, have to start at a place that humans mastered thousands of years ago. Uttering previously unheard signals and collectively establishing meaning. The question that this paper deals with is how can a communication system evolve if none of the conspirators have mastered the system previously using evolutionary computation and reinforcement learning

The influence of health literacy on the timely diagnosis of symptomatic cancer: A systematic review

Low health literacy has been associated with poor cancer screening uptake, difficulty in making treatment choices and reduced quality of life following a cancer diagnosis, yet it is unclear whether and how health literacy influences the pathway to diagnosis for patients with cancer symptoms. This systematic review aimed to evaluate the influence of health literacy on the timely diagnosis of symptomatic cancer. Literature was searched between January 1990 and May 2017 using MEDLINE, Embase, Scopus, ASSIA, CINAHL and PsycINFO. Only three papers met the inclusion criteria. These reported two qualitative studies and one quantitative, with adult patients diagnosed with gastrointestinal (colon, rectum and pancreas), cervical and breast cancer. The definition and assessment of health literacy varied between the studies, as did the descriptions of the pathway to diagnosis. Due to the methodological weaknesses identified, the conclusions are limited; however, the studies did highlight important considerations in the definition and measurement of health literacy. Further research is required that clearly defines health literacy and follows the principles of the Aarhus Statement to assess the influence of health literacy on the pathway to cancer diagnosis. The protocol for this review was registered with PROSPERO (CRD42016048917)