Trypanosomes have divergent kinesin-2 proteins that function differentially in flagellum biosynthesis and cell viability.

Trypanosoma brucei, the causative agent of African sleeping sickness, has a flagellum that is crucial for motility, pathogenicity, and viability. In most eukaryotes, the intraflagellar transport (IFT) machinery drives flagellum biogenesis, and anterograde IFT requires kinesin-2 motor proteins. In this study, we investigated the function of the two T. brucei kinesin-2 proteins, TbKin2a and TbKin2b, in bloodstream form trypanosomes. We found that, compared to kinesin-2 proteins across other phyla, TbKin2a and TbKin2b show greater variation in neck, stalk and tail domain sequences. Both kinesins contributed additively to flagellar lengthening. Silencing TbKin2a inhibited cell proliferation, cytokinesis and motility, whereas silencing TbKin2b did not. TbKin2a was localized on the flagellum and colocalized with IFT components near the basal body, consistent with it performing a role in IFT. TbKin2a was also detected on the flagellar attachment zone, a specialized structure that connects the flagellum to the cell body. Our results indicate that kinesin-2 proteins in trypanosomes play conserved roles in flagellar biosynthesis and exhibit a specialized localization, emphasizing the evolutionary flexibility of motor protein function in an organism with a large complement of kinesins.

Identification of Phytotoxic Levels of Copper and Nickel in Commercial Organic Soil Amendments Recycled from Poultry Farms and Municipal Wastes.

Commercial-scale recycling of agricultural and municipal wastes into organic soil amendments facilitates safe disposal of waste and reduces environmental contamination. However, phytotoxicity of commercial organic amendments to crops is a major concern to farmers. Consistent with this, commercial chicken manure and Milorganite (recycled from municipal waste) were found to be phytotoxic. Chicken manure aqueous extract contains 10.8 ppm Cu and 0.7 ppm Ni. The level of Cu and Ni in Milorganite is lower. The current study identified an aqueous solution containing 5 ppm Cu, lower than in chicken manure aqueous extract, was highly phytotoxic to mustard seeds germination. Therefore, phytotoxicity of chicken manure is in part due to Cu. An aqueous solution containing 1 ppm Ni was not phytotoxic; whereas 0.125 ppm Ni was phytotoxic when 62.5 ppm Na, which is nontoxic, was added to the solution. Therefore, synergistic effects of chemicals in the organic amendments may induce phytotoxicity.

Movement Demands of an Elite Cricket Team During the Big Bash League in Australia.

There is a lack of research on the movement patterns within Twenty20 (T20) cricket, thus the purpose of this study was to investigate the movement demands placed on elite T20 cricket players playing in The Big Bash League, in Australia, in the 2017/2018 season. Player positional movements were determined from the time motion data obtained from a portable 10 Hz global positioning (GPS) unit. Overall, all the players covered between 1.77km and 6.54km in a time ranging between 40.4 minutes and 96.5 minutes. Fast bowlers covered a mean distance of 6.5 (±0.5) km, batsmen 1.7 (±1.2) km and fielders 5.9 (±0.9) km. This is the first study that has looked at the movement demands of players in The Big Bash League and found that bowlers have the highest movement demands followed by fielding. With that, arguably, more attention needs to be devoted to bowling and particularly fielding which is often not prioritized. However, overall demands of T20 cricketers have decreased. Cricketers and coaches need to ensure that they adapt training to ensure that their players are physically prepared for the associated demands.

Experience-enabled enhancement of adult visual cortex function.

We previously reported in adult mice that visuomotor experience during monocular deprivation (MD) augmented enhancement of visual-cortex-dependent behavior through the non-deprived eye (NDE) during deprivation, and enabled enhanced function to persist after MD. We investigated the physiological substrates of this experience-enabled form of adult cortical plasticity by measuring visual behavior and visually evoked potentials (VEPs) in binocular visual cortex of the same mice before, during, and after MD. MD on its own potentiated VEPs contralateral to the NDE during MD and shifted ocular dominance (OD) in favor of the NDE in both hemispheres. Whereas we expected visuomotor experience during MD to augment these effects, instead enhanced responses contralateral to the NDE, and the OD shift ipsilateral to the NDE were attenuated. However, in the same animals, we measured NMDA receptor-dependent VEP potentiation ipsilateral to the NDE during MD, which persisted after MD. The results indicate that visuomotor experience during adult MD leads to enduring enhancement of behavioral function, not simply by amplifying MD-induced changes in cortical OD, but through an independent process of increasing NDE drive in ipsilateral visual cortex. Because the plasticity is resident in the mature visual cortex and selectively effects gain of visual behavior through experiential means, it may have the therapeutic potential to target and non-invasively treat eye- or visual-field-specific cortical impairment.

The influence of lactation on insulin and glucose metabolism, lipid profile, and cytokines in pregnant mares.

Glucose metabolism adapts to gestation, resulting in progressive physiological insulin resistance and increased insulin secretion to maintain maternal euglycemia and glucose availability for the developing fetus. These changes can impact mare fertility and maternal and neonatal health. This is the first comparison of body condition, regional adiposity, insulin and glucose dynamics, lipid metabolism, and cytokine production between lactating and non-lactating mares before, during pregnancy, and early postpartum. Twelve pregnancies from 9 broodmares, five nonlactating (NL) and seven lactating (L), were used. Evaluations were performed on the day of ovulation, at 55, 110, 165, 220, 275, and 330 days of gestation (D55, D110, D165, D220, D275, D330) and 21 days postpartum (21pp). Mares in the L group had lower basal insulin and glucose at the beginning of pregnancy, smaller area under the curve of insulin and glucose, and greater insulin sensitivity and glucose tolerance. Resistin was higher in D110 and D165 than in D0, D275, 330 and 21pp, while leptin was higher in D55, and in D110, at D110 it was equal to D0, D220, and D275, but higher than at D330 and D21pp. As for the groups, L presented lower body condition score (BCS), crest neck score (CNS), rump fat thickness (RUM), basal insulin, glucose area under the curve (AUCg), MIRG and higher RISQI, adiponectin and tumor necrosis factor (TNFα). There was no effect over time in non-esterified fatty acids (NEFA) concentrations between the L mares; in the NL, D275 presented higher concentrations than those of D0, D55, and D110, which in turn were equal to the other time points; there were higher concentrations in NL mares than L in samples D165 and D275. In conclusion, a different metabolic profile during pregnancy was detected, and NL mares were closer to the metabolic threshold for the occurrence of metabolic syndrome during pregnancy. Understanding the impacts of these differences on mare's health and their offspring's future is fundamental as most of our recipient mares for embryo transfer are non-lactating. Therefore, we suggest that further studies be performed to evaluate lactation's influence on mares' metabolic parameters.

Using mycobacterium cell wall fraction to decrease equine chorionic gonadotropin after abortion.

BACKGROUND: Equine embryonic loss following the development of endometrial cups delays return to cyclicity due to the production of equine chorionic gonadotropin (eCG). Natural degradation of endometrial cups coincides with an influx of immune cells at 100-120 days of gestation, but therapeutic stimulation of reduced eCG production has been relatively unsuccessful. Recently, we observed an increase in pro-inflammatory cytokine production following the use of the immunostimulant mycobacterium cell wall fraction (MCWF). OBJECTIVES: To evaluate the efficacy of hysteroscopic-guided injection of MCWF on the accelerated decline of eCG secretion. STUDY DESIGN: In vivo experiment. METHODS: Mares were pharmacologically aborted at 40-45 days of gestation, and then divided into groups: MCWF-treated (6 mg MCWF suspended in 20 mL LRS; n = 10) and Control (20 mL LRS; n = 6). Five days after abortion, hysteroscopic-guided injection of endometrial cups was performed, with 1 mL of volume placed into each visible endometrial cup. This was repeated 7 days later. Trans-rectal ultrasonography was performed to monitor ovarian activity, and serum was obtained to assess eCG and cytokine concentrations. RESULTS: Concentrations of eCG decreased in the MCWF-treated group (p < 0.01) with a significant suppression noted as early as 14 days after onset of treatment and remained suppressed for the duration of the study. This coincided with an increase in peripheral IFN-γ (p < 0.01) and IL-1ß (p < 0.01) concentrations. Eight out of ten MCWF-treated mares (80%) developed pre-ovulatory follicles, in comparison to 2/6 controls (33%). A pre-ovulatory follicle was noted 23 ± 4 days after onset of treatment. MAIN LIMITATIONS: No pregnancy data was obtained following treatment. CONCLUSIONS: This is the first report of a treatment for the accelerated reduction of eCG following abortion. Stimulation of this process allowed mares to develop a pre-ovulatory follicle within a month of MCWF treatment onset, granting repeat attempts at breeding within the confines of a single breeding season.

Elevated genetic structure in the coastal tailed frog (Ascaphus truei) in managed redwood forests.

Landscape alterations have dramatic impacts on the distribution of genetic variation within and among populations and understanding these effects can guide contemporary and future conservation strategies. We initiated a landscape-scale genetic study of the coastal tailed frog (Ascaphus truei) on commercial timberlands within the southern range of the species in Mendocino County (CA, USA). In total, 294 individuals from 13 populations were analyzed at 9 microsatellite loci. None of the sampled populations departed from mutation-drift equilibrium, indicating recent population bottlenecks were not detected in contemporary samples. Fine-scale analysis indicated sampled populations were structured at the watershed level (mean F (ST) = 0.077 and mean G'(ST) = 0.425). Landscape analyses suggested wet and moist areas may serve as significant corridors for gene flow within watersheds in this region (r (2) = 0.32-0.54 for moisture-related features). Results indicate populations of frogs may have persisted at this scale through intense periods of timber harvest, making southern range edge populations of coastal tailed frogs resilient to past land use practices.

FAZ assembly in bloodstream form Trypanosoma brucei requires kinesin KIN-E.

Trypanosoma brucei, the causative agent of African sleeping sickness, uses its flagellum for movement, cell division, and signaling. The flagellum is anchored to the cell body membrane via the flagellum attachment zone (FAZ), a complex of proteins, filaments, and microtubules that spans two membranes with elements on both flagellum and cell body sides. How FAZ components are carried into place to form this complex is poorly understood. Here, we show that the trypanosome-specific kinesin KIN-E is required for building the FAZ in bloodstream-form parasites. KIN-E is localized along the flagellum with a concentration at its distal tip. Depletion of KIN-E by RNAi rapidly inhibits flagellum attachment and leads to cell death. A detailed analysis reveals that KIN-E depletion phenotypes include failure in cytokinesis completion, kinetoplast DNA missegregation, and transport vesicle accumulation. Together with previously published results in procyclic form parasites, these data suggest KIN-E plays a critical role in FAZ assembly in T. brucei.

Social complexity, life-history and lineage influence the molecular basis of castes in vespid wasps.

A key mechanistic hypothesis for the evolution of division of labour in social insects is that a shared set of genes co-opted from a common solitary ancestral ground plan (a genetic toolkit for sociality) regulates caste differentiation across levels of social complexity. Using brain transcriptome data from nine species of vespid wasps, we test for overlap in differentially expressed caste genes and use machine learning models to predict castes using different gene sets. We find evidence of a shared genetic toolkit across species representing different levels of social complexity. We also find evidence of additional fine-scale differences in predictive gene sets, functional enrichment and rates of gene evolution that are related to level of social complexity, lineage and of colony founding. These results suggest that the concept of a shared genetic toolkit for sociality may be too simplistic to fully describe the process of the major transition to sociality.

Ruling out and ruling in neural codes.

The subject of neural coding has generated much debate. A key issue is whether the nervous system uses coarse or fine coding. Each has different strengths and weaknesses and, therefore, different implications for how the brain computes. For example, the strength of coarse coding is that it is robust to fluctuations in spike arrival times; downstream neurons do not have to keep track of the details of the spike train. The weakness, though, is that individual cells cannot carry much information, so downstream neurons have to pool signals across cells and/or time to obtain enough information to represent the sensory world and guide behavior. In contrast, with fine coding, individual cells can carry much more information, but downstream neurons have to resolve spike train structure to obtain it. Here, we set up a strategy to determine which codes are viable, and we apply it to the retina as a model system. We recorded from all the retinal output cells an animal uses to solve a task, evaluated the cells' spike trains for as long as the animal evaluates them, and used optimal, i.e., Bayesian, decoding. This approach makes it possible to obtain an upper bound on the performance of codes and thus eliminate those that are insufficient, that is, those that cannot account for behavioral performance. Our results show that standard coarse coding (spike count coding) is insufficient; finer, more information-rich codes are necessary.

Model for Teaching the Helping Babies Survive Course Series and Advanced Life Support in Obstetrics Workshops to Rural Skilled Birth Attendants in Uganda.

Background: Uganda, like much of Sub-Saharan Africa and other underserved regions continues to face the challenge of high neonatal and maternal mortality. The Helping Babies Survive (HBS) course and the Advanced Life Support in Obstetrics (ALSO) provide hands on education to train providers in key life-saving interventions. A uterine balloon tamponade (UBT) procedure can be life-saving in the event of uterine bleeding. The purpose of this implementation research is to gain more insight into the effectiveness of a tailored down 5-day combined HBS-ALSO-UBT course. In this study, we found that a tailored down 5-day combined HBS-ALSO-UBT could be performed with significantly improved self-assessment in diagnosing and managing a wide range of peripartum conditions.

Neuronal death during combined intermittent hypoxia/hypercapnia is due to mitochondrial dysfunction.

Breathing-disordered states, such as in obstructive sleep apnea, which are cyclical in nature, have been postulated to induce neurocognitive morbidity in both pediatric and adult populations. The oscillatory nature of intermittent hypoxia, especially when chronic, may mimic the paradigm of ischemia-reperfusion in that tissues and cells are exposed to episodes of low and high O(2) and this may lead to oxidant stress. Therefore, we decided to explore the potential contribution of oxidant stress in our intermittent hypoxia/hypercapnia animal model and the role that mitochondria might play in this stress. Neonatal mice were exposed to intermittent hypoxia/hypercapnia for 10 days and 2 wk. Combined intermittent hypoxia/hypercapnia led to a marked increase in apoptotic cell death in the cerebral cortex. Oxygen consumption studies in isolated mitochondria from intermittent hypoxia/hypercapnia-exposed brains demonstrated significant reductions in both state 4 and state 3 respiratory activities by approximately 60% and 75%, respectively. Electron paramagnetic resonance spectroscopy registered a significant increase in superoxide production during nonphosphorylating state 4 by 37%, although superoxide leakage during state 3 did not increase upon treatment. Neuronal superoxide-specific dihydroethidium oxidation was also greater in exposed animals. These studies indicate that intermittent hypoxia/hypercapnia leads to oxidative stress due to mitochondrial response within the mouse central nervous system.

Epidermal growth factor receptor translocation to the mitochondria: regulation and effect.

Co-overexpression of the epidermal growth factor (EGF) receptor (EGFR) and c-Src frequently occurs in human tumors and is linked to enhanced tumor growth. In experimental systems this synergistic growth requires EGF-dependent association of c-Src with the EGFR and phosphorylation of Tyr-845 of the receptor by c-Src. A search for signaling mediators of Tyr(P)-845 revealed that mitochondrial cytochrome c oxidase subunit II (CoxII) binds EGFR in a Tyr(P)-845- and EGF-dependent manner. In cells this association involves translocation of EGFR to the mitochondria, but regulation of this process is ill-defined. The current study demonstrates that c-Src translocates to the mitochondria with similar kinetics as EGFR and that the catalytic activity of EGFR and c-Src as well as endocytosis and a mitochondrial localization signal are required for these events. CoxII can be phosphorylated by EGFR and c-Src, and EGF stimulation reduces Cox activity and cellular ATP, an event that is dependent in large part on EGFR localized to the mitochondria. These findings suggest EGFR plays a novel role in modulating mitochondrial function via its association with, and modification of CoxII.

Insulin/PI3K signaling protects dentate neurons from oxygen-glucose deprivation in organotypic slice cultures.

It is known that ischemia/reperfusion induces neurodegeneration in the hippocampus in a subregion-dependent manner. This study investigated the mechanism of selective resistance/vulnerability to oxygen-glucose deprivation (OGD) using mouse organotypic hippocampal cultures. Analysis of propidium iodide uptake showed that OGD-induced duration- and subregion-dependent neuronal injury. When compared with the CA1-3 subregions, dentate neuronal survival was more sensitive to inhibition of phosphatidylinositol 3-kinase (PI3K)/Akt signaling under basal conditions. Dentate neuronal sensitivity to PI3K/Akt signaling activation was inversely related to its vulnerability to OGD-induced injury; insulin/insulin-like growth factor 1 pre-treatment conferred neuroprotection to dentate neurons via activation of PI3K/Akt signaling. In contrast, CA1 and CA3 neurons were less sensitive to disruptions of endogenous PI3K/Akt signaling and protective effects of insulin/insulin-like growth factor 1, but more vulnerable to OGD. OGD-induced injury in CA1 was reduced by inhibition of NMDA receptor or mitogen-activated protein kinase signaling, and was prevented by blocking NMDA receptor in the presence of insulin. The CA2 subregion was distinctive in its response to glutamate, OGD, and insulin, compared with other CA subregions. CA2 neurons were sensitive to the protective effects of insulin against OGD-induced injury, but more resistant to glutamate. Distinctive distribution of insulin receptor beta and basal phospho-Akt was detected in our slice cultures. Our results suggest a role for insulin signaling in subregional resistance/vulnerability to cerebral ischemia.

Pneumonia in Papua New Guinea, from the past to the future.

This paper briefly describes a journey with pneumonia and the pneumococcus that began in partnership with Ian Riley at the Lae Hospital in 1967 and continues 43 years later. It is a journey that signalled the global emergence of penicillin-resistant pneumococci and played an important role in the licensure of pneumococcal polysaccharide vaccine for use in adults around the world. The journey involved many other people whose experience began in Papua New Guinea (PNG), playing lead roles in the global program to reduce pneumonia deaths in developing countries. But none of this has benefitted Papua New Guineans as it could and should have done. In this paper I assert that substantial benefits could now follow from widespread use of the 23-valent polysaccharide vaccine in PNG adults not suffering from HIV and that there is also good scientific reason why children over the age of 9 months should be offered the potential benefits from use of this vaccine that were demonstrated in PNG in the 1980s. Indeed there are very good medical and economic reasons why it should happen.

Addressing the corona virus pandemic: will a novel filtered eye mask help?

OBJECTIVE: Non-hermetically sealed eye protection does not fully protect the eyes from airborne particles. Hermetically sealed eye protection fully protects the eyes from particles, but tends to fog up, rendering it unusable. This study aimed to build and test a filtered eye mask (FEM) to protect the eyes from airborne particles, while being usable without excessive fog build up. METHODS: The steps performed to build the FEM were described. A hermetically-sealed standard eye mask (SEM) and an FEM were examined at 1-minute, 5-minute and 60-minute periods for performance metrics relating to fog. RESULTS: The SEM showed minimal fog at 1minute, lots of fog at 5minutes and was dripping with condensation at 60minutes. The FEM was clear at 1minute, 5minutes and showed minimal fog at 60minutes. CONCLUSION: An FEM may play an important role in preventing novel coronavirus (COVID-19) exposure by protecting the eyes from airborne particles and preventing fog, rendering it usable. Further research is strongly recommended.

Uterine responses and equine chorionic gonadotropin concentrations after two intrauterine infusions with kerosene post early fetal loss in mares.

Pregnancy loss during the normal lifespan of endometrial cups (∼37-120-150 days of gestation) may affect a mare's ability to conceive again in the same breeding season, as equine chorionic gonadotropin (eCG) secretion by retained endometrial cups can lead to abnormal ovulations and follicular growth. While intrauterine kerosene infusion has anecdotally been proposed as a treatment for endometrial cup retention, there are no controlled studies evaluating kerosene's ability to enhance endometrial cup regression following abortion. The objectives of this study were to assess uterine response, systemic side effects, and efficacy of intrauterine kerosene infusions after abortion. We hypothesized that kerosene infusions would hasten regression of endometrial cups without detrimental effects on the endometrium and the mare's general health. Twelve light-breed mares were enrolled in the study after an experimentally induced abortion with cloprostenol (n = 12) by 60 ± 2 days of gestation. Mares were randomly allocated to receive an intrauterine infusion with 500 mL of kerosene (n = 6) or 500 mL saline (n = 6) on days 21 and 35 after pregnancy termination. Uterine biopsies were collected at days 7, 21, 35, and 49 post-abortion to evaluate the degree of endometrial fibrosis with Picrosirius Red Stain and to be graded according to the Kenney & Doig 1986 classification. Furthermore, histomorphometry analysis of the endometrium lining, glandular epithelium and glandular density was performed. Endometrial lymphocyte B CD20+, lymphocyte T CD3+, and macrophage IBA-1+ cell populations were characterized by immunohistochemistry. Physical examinations, blood cell counts, and serum biochemistry were performed before, and for 2 days after each uterine infusion. Serum samples were collected for assessment of eCG concentrations. Continuous data were analyzed with MIXED procedure with repeated measures in SAS, categorical data with LOGISTIC procedure of SAS. Significance was set at p < 0.05. Kerosene infusion did not affect complete blood cell counts, serum chemistry parameters, or physical examinations. Concentrations of eCG decreased over time (p < 0.001), but there were no differences between groups or time by group interactions (p = 0.72). Histological evaluation of the uterus showed no signs of increased fibrosis or degeneration in the treatment group. In conclusion, while kerosene infusions did not appear to have detrimental effects on mare health, our findings suggest that the use of kerosene in the uterus does not enhance the regression of endometrial cups by 49 days post-abortion.

Experience-dependent plasticity from eye opening enables lasting, visual cortex-dependent enhancement of motion vision.

Developmentally regulated plasticity of vision has generally been associated with "sensitive" or "critical" periods in juvenile life, wherein visual deprivation leads to loss of visual function. Here we report an enabling form of visual plasticity that commences in infant rats from eye opening, in which daily threshold testing of optokinetic tracking, amid otherwise normal visual experience, stimulates enduring, visual cortex-dependent enhancement (>60%) of the spatial frequency threshold for tracking. The perceptual ability to use spatial frequency in discriminating between moving visual stimuli is also improved by the testing experience. The capacity for inducing enhancement is transitory and effectively limited to infancy; however, enhanced responses are not consolidated and maintained unless in-kind testing experience continues uninterrupted into juvenile life. The data show that selective visual experience from infancy can alone enable visual function. They also indicate that plasticity associated with visual deprivation may not be the only cause of developmental visual dysfunction, because we found that experientially inducing enhancement in late infancy, without subsequent reinforcement of the experience in early juvenile life, can lead to enduring loss of function.

Overexpression of 5 alpha-reductase type 1 increases sensitivity of prostate cancer cells to low concentrations of testosterone.

INTRODUCTION: Conversion of testosterone to dihydrotestosterone (DHT) by the enzymes 5 alpha-reductase types 1 (5 alpha R1) and 2 (5 alpha R2) is important for normal and pathological growth of the prostate. The predominant isoenzyme in normal prostate is 5 alpha R2. However, prostate cancer (PCa) development is accompanied by a decrease in 5 alpha R2 and an increase in 5 alpha R1. The biological significance of increased 5 alpha R1 expression is not fully understood. Therefore, the aim of this study was to determine the effect of overexpression of 5 alpha R1 on growth and prostate-specific antigen (PSA) production in PCa cells. MATERIALS AND METHODS: LNGK-9 PCa cells, transiently transfected with pTRE-5 alpha R1 or pTRE alone, were cultured in the presence or absence of testosterone at varying concentrations. Cell growth and PSA secretion were measured after 4-6 days. Cyclin E1, Ki67, and PSA mRNA levels were evaluated using RT-PCR after 24 hr of treatment. RESULTS: 10 pM testosterone increased growth of pTRE-5 alpha R1 transfectants by 54.1% over cells grown in the absence of testosterone, compared to 25.0% in pTRE transfectants (P < 0.01). Likewise, PSA secretion was increased by 56-fold in pTRE-5 alpha R1 transfectants treated with 10 pM testosterone, compared to 26-fold in pTRE transfectants (P < 0.01). At concentrations of testosterone above 10 pM, the stimulatory effect on growth and PSA secretion was not distinguishable between pTRE-5 alpha R1 and pTRE transfectants. CONCLUSIONS: These results demonstrate that upregulation of 5 alpha R1 enhances the cellular response to low, but not high, concentrations of testosterone. This explains one mechanism by which castration-recurrent PCa can proliferate in the presence of castrate levels of circulating testosterone.