Gas exchanges by Phymatotrichum omnivorum in a closed,axenic system

Gas exchanges byPhymatotrichum omnivorum were studied in a closed, axenic system. The fungus liberated CO₂ and ethylene, and appeared to utilize N₂. Over a 44-day test period, CO₂ increased from 0.1 to 312.8 ml/liter. Oxygen decreased from 211 to 17.8 ml/liter and N₂ decreased from 789 to 669.5 ml/liter during the same period. The combined uptake of N₂ and O₂ was equal to the release of CO₂ in the ambient gas.A rapid increase in ethylene was observed 14 to 28 days after the flasks were inoculated (15 to 160 nliter/liter). Mycelial strands and sclerotial initials formed on the flask sides, but mature sclerotia did not develop.Supported in part by Cooperative Agreement 70-178 from Cotton Incorporated. A contribution of the Texas Agricultural Experiment Station.     

Some self-consistent two-state sliding filament models of muscle contraction.

The general formalism required to treat two-state sliding filament models of muscle contraction, including free energy considerations, is first reviewed and amplified. This formalism is then used to examine, and modify as needed, three models studied previously by Podolsky and Nolan, in which cross-bridge attachment-detachment and ATP turnover are not tightly coupled. No attempt is made here to establish an optimal, self-consistent model of this type because our interest is primarily in methadology rather than in fitting experimental results. But it appears from this preliminary study that such a model, with satisfactory mechanical and thermodynamic properties, could be found. An extremely simple but unrealistic two-state model is also studied which is of interest because it demonstrates the fact that it is possible, in principle at least, for sliding filament models to work with very high thermodynamic efficiencies (50-100 percent). An appendix is included that is concerned with the form of the dependence of certain first-order rate constants on the concentrations of ATP, ADP, and P.     

Influence of nutrition on reproduction in the ewe with special emphasis on progesterone concentration.

Influence of nutrition on lambing rate and progesterone levels was studied in Rambouillet ewes. In the first experiment, two groups of 10 ewes each were individually fed on a diet containing either high (3.04 kg/day) or low (1.89 kg/day) levels of total digestible nutrients. Ewes on the High Plane of nutrition had lower pregnancy rates and fewer lambs than the ewes on the Low Plane. Plasma progesterone concentration was not significantly different between treatment groups when compared before and after mating.In the second experiment two groups of 25 ewes each were grazed on pasture and supplemented with a pelleted concentrate. One group was fed to gain weight, while the other group was fed to maintain their body weight. There was no significant difference in lambing rate between these two groups.     

Methodichlorophen as anti-tumor drug.

Methodichlorophen was given to 26 patients with terminal malignant disease. Eight patients received adequate doses, and five of them showed objective evidence of tumour regression while three failed to respond. Those who responded included four out of five patients with lung cancer (three with squamous-cell carcinoma and one with oat-cell carcinoma) and a patient with hypernephroma. Two patients with testicular teratomas and one with acute myeloid leukemia failed to respond. The drug may be given safely by mouth to outpatients if certain precautions are taken.     

Making genomic surveillance deliver: A lineage classification and nomenclature system to inform rabies elimination

The availability of pathogen sequence data and use of genomic surveillance is rapidly increasing. Genomic tools and classification systems need updating to reflect this. Here, rabies virus is used as an example to showcase the potential value of updated genomic tools to enhance surveillance to better understand epidemiological dynamics and improve disease control. Previous studies have described the evolutionary history of rabies virus, however the resulting taxonomy lacks the definition necessary to identify incursions, lineage turnover and transmission routes at high resolution. Here we propose a lineage classification system based on the dynamic nomenclature used for SARS-CoV-2, defining a lineage by phylogenetic methods for tracking virus spread and comparing sequences across geographic areas. We demonstrate this system through application to the globally distributed Cosmopolitan clade of rabies virus, defining 96 total lineages within the clade, beyond the 22 previously reported. We further show how integration of this tool with a new rabies virus sequence data resource (RABV-GLUE) enables rapid application, for example, highlighting lineage dynamics relevant to control and elimination programmes, such as identifying importations and their sources, as well as areas of persistence and routes of virus movement, including transboundary incursions. This system and the tools developed should be useful for coordinating and targeting control programmes and monitoring progress as countries work towards eliminating dog-mediated rabies, as well as having potential for broader application to the surveillance of other viruses.     

SARS-CoV-2 seropositivity and COVID-19 among 5 years-old Amazonian children and their association with poverty and food insecurity

BackgroundThe epidemiology of childhood SARS-CoV-2 infection and COVID-19-related illness remains little studied in high-transmission tropical settings, partly due to the less severe clinical manifestations typically developed by children and the limited availability of diagnostic tests. To address this knowledge gap, we investigate the prevalence and predictors of SARS-CoV-2 infection (either symptomatic or not) and disease in 5 years-old Amazonian children.Methodology/Principal findingsWe retrospectively estimated SARS-CoV-2 attack rates and the proportion of infections leading to COVID-19-related illness among 660 participants in a population-based birth cohort study in the Juruá Valley, Amazonian Brazil. Children were physically examined, tested for SARS-CoV-2 IgG and IgM antibodies, and had a comprehensive health questionnaire administered during a follow-up visit at the age of 5 years carried out in January or June-July 2021. We found serological evidence of past SARS-CoV-2 infection in 297 (45.0%; 95% confidence interval [CI], 41.2–48.9%) of 660 cohort participants, but only 15 (5.1%; 95% CI, 2.9–8.2%) seropositive children had a prior medical diagnosis of COVID-19 reported by their mothers or guardians. The period prevalence of clinically apparent COVID-19, defined as the presence of specific antibodies plus one or more clinical symptoms suggestive of COVID-19 (cough, shortness of breath, and loss of taste or smell) reported by their mothers or guardians since the pandemic onset, was estimated at 7.3% (95% CI, 5.4–9.5%). Importantly, children from the poorest households and those with less educated mothers were significantly more likely to be seropositive, after controlling for potential confounders by mixed-effects multiple Poisson regression analysis. Likewise, the period prevalence of COVID-19 was 1.8-fold (95%, CI 1.2–2.6-fold) higher among cohort participants exposed to food insecurity and 3.0-fold (95% CI, 2.8–3.5-fold) higher among those born to non-White mothers. Finally, children exposed to household and family contacts who had COVID-19 were at an increased risk of being SARS-CoV-2 seropositive and–even more markedly–of having had clinically apparent COVID-19 by the age of 5 years.Conclusions/SignificanceChildhood SARS-CoV-2 infection and COVID-19-associated illness are substantially underdiagnosed and underreported in the Amazon. Children in the most socioeconomically vulnerable households are disproportionately affected by SARS-CoV-2 infection and disease.