Abiotic environmental variation drives virulence evolution in a fish host-parasite geographic mosaic

1. Parasite virulence varies greatly. Theory predicts that this arises from parasites optimising a trade-off between the mortality they inflict on current hosts, and their transmission to future hosts. The effect of the environment on this coevolution is rarely considered. 2. Geographic mosaics are fertile systems for studying coevolution, but again, the diversity of outcomes is often assumed to result from co-evolutionary dynamism, rather than being moulded by the environment. 3. Here we quantify variation in virulence among lakes in a geographic mosaic of coevolution between a trematode ectoparasite (Gyrodactylus arcuatus) and its three-spined stickleback(Gasterosteus aculeatus) host. 4. Virulence varies greatly in this system, and parasites are generally locally adapted to their hosts. 5. Parasites are also locally adapted to the water in their own lake, and virulence is strongly related to lake pH, the dominant axis of abiotic environmental variation in this system. 6. These results suggest that the evolution of virulence can be substantially affected by the abiotic environment, which has important implications for understanding coevolution. There are also implications for the evolutionary management of disease e.g. ectoparasites in aquaculture, the impacts of which might be expected to reduce given ongoing acidification of aquatic ecosystems

INVESTIGATION OF THYROIDS DYSFUNCTION AMONG INFERTILE WOMEN IN NASIRIYAH CITY

Objective: Epidemiological studies revealed that 10-15 % of couples in the world experience infertility. Thyroid dysfunction (hyperthyroidism and hypothyroidism) possessed adverse effect on reproductive health and resulted in, interference with ovulation, reduced rates of conception, increased early pregnancy loss, and adverse effects on pregnancy and neonatal outcomes. The current study aims to explore the thyroid dysfunction among infertile women in Nasiriyah city-Iraq. Methods: The study was conducted on 60 infertile women (age group 17–45 y) who visited infertility departments in Al-Hussein hospital, Al-Haboubi hospital and Bent AL Huda hospital, in Nasiriyah city, from October 2019 to March 2020. Thirty normal females (age matched) were taken as controls. TSH, T3, T4, LH, FSH, prolactin, progesterone and estradiol levels were determine by using VIDAS® Assay. Results: The prevalence of hyperthyroidism among infertile women was 13.33% and hypothyroidism was 10.00%. Both hyper and hypothyroidism induced adverse changes in the serum levels of LH, FSH, prolactin and gonadal hormones. Conclusion: Thyroid dysfunction was associated with a risk of not getting pregnancy. Women were advised to achieve euthyroidism before planning a pregnancy

Prior exposure to long-day photoperiods alters immune responses and increases susceptibility to parasitic infection in stickleback

Seasonal disease and parasitic infection are common across organisms, including humans, and there is increasing evidence for intrinsic seasonal variation in immune systems. Changes are orchestrated through organisms' physiological clocks using cues such as day length. Ample research in diverse taxa has demonstrated multiple immune responses are modulated by photoperiod, but to date, there have been few experimental demonstrations that photoperiod cues alter susceptibility to infection. We investigated the interactions among photoperiod history, immunity and susceptibility in laboratory-bred three-spined stickleback (a long-day breeding fish) and its external, directly reproducing monogenean parasite Gyrodactylus gasterostei. We demonstrate that previous exposure to long-day photoperiods (PLD) increases susceptibility to infection relative to previous exposure to short days (PSD), and modifies the response to infection for the mucin gene muc2 and Treg cytokine foxp3a in skin tissues in an intermediate 12 L : 12 D photoperiod experimental trial. Expression of skin muc2 is reduced in PLD fish, and negatively associated with parasite abundance. We also observe inflammatory gene expression variation associated with natural inter-population variation in resistance, but find that photoperiod modulation of susceptibility is consistent across host populations. Thus, photoperiod modulation of the response to infection is important for host susceptibility, highlighting new mechanisms affecting seasonality of host-parasite interactions

Environmental Microcystin Targets the Microbiome and Increases the Risk of Intestinal Inflammatory Pathology via NOX2 in Underlying Murine Model of Nonalcoholic Fatty Liver Disease

With increased climate change pressures likely to influence harmful algal blooms, exposure to microcystin, a known hepatotoxin and a byproduct of cyanobacterial blooms can be a risk factor for NAFLD associated comorbidities. Using both in vivo and in vitro experiments we show that microcystin exposure in NAFLD mice cause rapid alteration of gut microbiome, rise in bacterial genus known for mediating gut inflammation and lactate production. Changes in the microbiome were strongly associated with inflammatory pathology in the intestine, gut leaching, tight junction protein alterations and increased oxidative tyrosyl radicals. Increased lactate producing bacteria from the altered microbiome was associated with increased NOX-2, an NADPH oxidase isoform. Activationof NOX2 caused inflammasome activation as shown by NLRP3/ASCII and NLRP3/Casp-1 colocalizations in these cells while use of mice lacking a crucial NOX2 component attenuated inflammatory pathology and redox changes. Mechanistically, NOX2 mediated peroxynitrite species were primary to inflammasome activation and release of inflammatory mediators. Thus, in conclusion, microcystin exposure in NAFLD could significantly alter intestinal pathology especially by the effects on microbiome and resultant redox status thus advancing our understanding of the co-existence of NAFLD-linked inflammatory bowel disease phenotypes in the clinic

Staged humerus lengthening with monolateral fixation followed by a circular frame: Technique of fixator change

Monolateral external fixator (MEF) has been commonly used for limb lengthening in both upper and lower extremities. Since MEF can only lengthen or shorten the bone, sagittal, coronal, and torsional deformities need to be corrected acutely at the time of MEF application. Acute correction, particularly torsional correction, may endanger the radial or peroneal nerves. Gradual correction of torsion may be safely achieved using a circular external fixator (CEF) frame. We present a case study of humeral lengthening with derotation to describe a technique, whereby it is possible to first lengthen with MEF and then derotate with CEF. This is a case report of a 14-year-old boy with a history of neonatal sepsis and growth arrest of the proximal humerus that led to a short right humerus and loss of external rotation. Humerus lengthening was achieved (6.6 cm) using MEF. Conversion to CEF was done after the distraction phase and prior to regenerate bone consolidation. Two 2/3 rings were connected to the proximal and distal fixation half-pins, and then the six connecting struts were added. The rotation deformity correction was then performed gradually to achieve 60° of external rotation. The described technique to convert the MEF into CEF is versatile and can be employed in the clinic safely and without sedation

Abiotic environmental variation drives virulence evolution in a fish host-parasite geographic mosaic

1. Parasite virulence varies greatly. Theory predicts that this arises from parasites optimising a trade-off between the mortality they inflict on current hosts, and their transmission to future hosts. The effect of the environment on this coevolution is rarely considered. 2. Geographic mosaics are fertile systems for studying coevolution, but again, the diversity of outcomes is often assumed to result from co-evolutionary dynamism, rather than being moulded by the environment. 3. Here we quantify variation in virulence among lakes in a geographic mosaic of coevolution between a trematode ectoparasite (Gyrodactylus arcuatus) and its three-spined stickleback(Gasterosteus aculeatus) host. 4. Virulence varies greatly in this system, and parasites are generally locally adapted to their hosts. 5. Parasites are also locally adapted to the water in their own lake, and virulence is strongly related to lake pH, the dominant axis of abiotic environmental variation in this system. 6. These results suggest that the evolution of virulence can be substantially affected by the abiotic environment, which has important implications for understanding coevolution. There are also implications for the evolutionary management of disease e.g. ectoparasites in aquaculture, the impacts of which might be expected to reduce given ongoing acidification of aquatic ecosystems

Gasterosteus and Gyrodactylus: results of artificial infection experiments showing local adaptation

The file contains the results from five experiments. Experiments 1 to 4 show the outcome of artificial infections of stickleback hosts from different populations (lakes) with Gyrodactylus parasites from different lakes. Data shown are the populations of origin of the host and parasite, the sex, length (mm) and family (where applicable) of hosts, and the total number of parasites counted on the host over the course of the experiment. Different experiments are for different combinations of host and parasite populations, and had slightly different experimental conditions (e.g. number of parasites used to start an infection, and frequency of counts). Experiment 5 shows the results (in hours until death) of an experiment in which parasites from different lakes (and detached from hosts), were reciprocally exposed to water from the same lakes

Data from: Abiotic environmental variation drives virulence evolution in a fish host-parasite geographic mosaic

1.Parasite virulence varies greatly. Theory predicts that this arises from parasites optimising a trade-off between the mortality they inflict on current hosts, and their transmission to future hosts. The effect of the environment on this coevolution is rarely considered. 2.Geographic mosaics are fertile systems for studying coevolution, but again, the diversity of outcomes is often assumed to result from co-evolutionary dynamism, rather than being moulded by the environment. 3.Here we quantify variation in virulence among lakes in a geographic mosaic of coevolution between a trematode ectoparasite (Gyrodactylus arcuatus) and its three-spined stickleback (Gasterosteus aculeatus) host. 4.Virulence varies greatly in this system, and parasites are generally locally adapted to their hosts. 5.Parasites are also locally adapted to the water in their own lake, and virulence is strongly related to lake pH, the dominant axis of abiotic environmental variation in this system. 6.These results suggest that the evolution of virulence can be substantially affected by the abiotic environment, which has important implications for understanding coevolution. There are also implications for the evolutionary management of disease e.g. ectoparasites in aquaculture, the impacts of which might be expected to reduce given ongoing acidification of aquatic ecosystems

Drug resistance-related mutations in multidrug-resistant Mycobacterium tuberculosis isolates from diverse geographical regions

Background: Drug resistance in Mycobacterium tuberculosis is associated with chromosomal mutations in selected genes. These mutations can be screened for an early warning system for drug-resistant tuberculosis. The prevalence of individual mutations differs geographically, which must be considered in developing globally applicable screening tests. Methods: In order to analyse the geographical distribution and frequency of mutations conferring resistance to rifampicin, isoniazid and fluoroquinolones, the researchers investigated the presence of mutations in the rpoB gene, the katG gene, the mabA-inhA promoter region and the gyrA gene in clinical isolates of multidrug-resistant tuberculosis (MDR-TB) from Belarus, China, Iran/Iraq, Honduras, Romania and Uganda. For each study site, the researchers described the distribution of specific mutations in 20 clinical MDR-isolates. Results: The distribution of resistance-related mutations varied significantly between the study sites. Settings with a high incidence of MDR-TB, such as Belarus, showed a narrower spectrum of mutations related to rifampicin and isoniazid resistance and also a higher prevalence of fluoroquinolone resistance than study sites with a lower MDR-TB prevalence. Conclusion: This study confirms that there are significant geographical differences in the distribution of resistance-related mutations and suggests that an increased understanding of such differences in the specific distribution of resistance conferring mutations is crucial for development of new, generally applicable, molecular tools for rapid diagnosis of drug-resistant TB. The fact that a narrower distribution of mutations in high MDR-TB prevalence settings was seen suggests that much of the problems in these settings can be a result of an ongoing transmission of certain MDR-TB strains