The impact of ectoparasitism on thermoregulation in Yarrow ’s Spiny Lizards (Sceloporus jarrovii)

Canadian Journal of Zoology, e-First Articles. Parasites are ubiquitous and can have large impacts on the fitness of their hosts. The effects of ectoparasites on physiology, behaviour, and immune function suggest that they could be part of the factors which impact thermoregulation. We tested the hypothesis that ectoparasites impact thermoregulation in Yarrow ’s Spiny Lizards (Sceloporus jarrovii Cope in Yarrow, 1875) living along an elevational gradient. We predicted a positive association between ectoparasite load and body temperature (Tb), and a negative association between ectoparasite load and effectiveness of thermoregulation (de – db index). W e also predicted that the impacts of ectoparasites would be greatest at high elevation where thermal quality of the environment is low because the costs of thermoregulation increase with elevation and these costs can impact thermal immune responses. We found a significant association between the num ber of chiggers (Trombiculoidea) harboured by lizards and Tb that depended on elevation, but no association between ectoparasite load and de – db index. The mean chigger infection rate was associated with a ΔTb of +0.18 °C at low elevation (consistent with fever) and of –1.07 °C at high eleva tion (consistent with hypothermia). These findings suggest that parasitism by chiggers impacts lizard Tb in a way that depends on environmental thermal quality.
Source: Canadian Journal of Zoology - Category: Zoology Authors: Source Type: research

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Conclusion: This paper features an autonomous, portable, 1-min analysis time, and low-cost per test device, without the need for samples, centrifugation, allowing the use of whole blood. Significance: The presented device is a step ahead for meeting the growing clinical demands for reliable, rapid, portable, and quantitative malaria diagnosis.
Source: IEEE Transactions on Biomedical Engineering - Category: Biomedical Engineering Source Type: research
This week's very cool case was donated by Dr. Mike Feely. We haven't had anything like this one before on the blog!The specimen below was submitted by a young woman who found this " worm " by her arm, right below her mouth, upon waking from a nap. She reported having abdominal pain with associated diarrhea for several weeks prior to presentation, but was otherwise healthy. After being in formalin:Histologic sections (H&E):Identification? Any additional information that you would like?
Source: Creepy Dreadful Wonderful Parasites - Category: Parasitology Source Type: blogs
Despite a 30% decline in mortality since 2000, malaria still affected 219 million subjects and caused 435,000 deaths in 2017. Red blood cells (RBC) host Plasmodium parasites that cause malaria, of which Plasmodium falciparum is the most pathogenic. The deformability of RBC is markedly modified by invasion and development of P. falciparum. Surface membrane area is potentially impacted by parasite entry and development, the cytoskeleton is modified by parasite proteins and cytosol viscosity is altered by parasite metabolism. RBC hosting mature parasites (second half of the asexual erythrocytic cycle) are abnormally stiff but...
Source: Frontiers in Physiology - Category: Physiology Source Type: research
Publication date: Available online 21 August 2019Source: Ticks and Tick-borne DiseasesAuthor(s): R. Megía-Palma, D. Paranjpe, P. Blaimont, R. Cooper, B. SinervoAbstractIt is generally accepted that parasites exert negative effects on their hosts and that natural selection favors specific host responses that mitigate this impact. It is also known that some components of the host immune system often co-evolve with parasite antigens resulting in a host-parasite arms race. In addition to immunological components of the anti-parasitic response, host behavioral responses are also important in this arms race and natural se...
Source: Ticks and Tick borne Diseases - Category: Zoology Source Type: research
This study was aimed at evaluating the antimalarial effect of leaf latex and isolates obtained from Aloe megalacantha against chloroquine sensitive Plasmodium berghei ANKA strain in Swiss albino mice. Peters' 4-day suppressive test method was used to test the antimalarial activity of both leaves latex and isolates. Three isolates were obtained using thin layer chromatography and were coded as AM1, AM2, and AM3 in ascending order of their retention factor. After treatment of Plasmodium berghei infected mice with leaf latex of Aloe megalacantha for four days at 100, 200, and 400 mg/kg, it shows 30.3%, 43.4%, and 56.4%...
Source: Evidence-based Complementary and Alternative Medicine - Category: Complementary Medicine Tags: Evid Based Complement Alternat Med Source Type: research
Abstract Plasmodium falciparum infection causes febrile illness and severe disease with multiple organ failure and death when treatment is delayed. Antipyretic treatment is standard, and inducing hypothermia has been proposed to protect the brain in cerebral malaria. Here, we investigated the temperature dependence of asexual-stage parasite development and parasite multiplication in vitro. Plasmodium falciparum laboratory strain TM267 was incubated for 2 hours (short exposure) or 48 hours (continuous exposure) at different temperatures (32°C, 34°C, 35°C, 38°C, 39°C, and 40°C). The starting ...
Source: The American Journal of Tropical Medicine and Hygiene - Category: Tropical Medicine Authors: Tags: Am J Trop Med Hyg Source Type: research
We examined the impact of short pulses of low temperature on ring-stage susceptibility of Plasmodium falciparum to artemisinin in vitro. The usually artemisinin-sensitive clone 3D7 exhibited substantially reduced ring-stage susceptibility to a 4-h pulse of 700 nM dihydro-artemisinin administered during a 5-h pulse of low temperature down to 17 °C. Parasite growth through the subsequent asexual cycle was not affected by the temperature pulse. Chloroquine and pyronaridine susceptibility, in a standard 48-h test, was not affected by brief exposures to low temperature. Fever-like temperature pulses up to 40 °C we...
Source: International Journal for Parasitology: Drugs and Drug Resistance - Category: Parasitology Source Type: research
We report a case of left-sided renal cell carcinoma (RCC) with level 4 cavoatrial tumor thrombus where robotic assistance was used to achieve hemostasis around the kidney in order to minimize coagulopathic hemorrhage from the nephrectomy bed during subsequent open completion nephrectomy and cavoatrial thrombectomy under extracorporeal circulation and hypothermic circulatory arrest. Robotic assistance allowed for meticulous dissection and ligation of parasitic and arterial vessels to the kidney, release of renal attachments, and exposure of the inferior vena cava. The kidney was mobilized while leaving the renal vein attach...
Source: Journal of Robotic Surgery - Category: Surgery Source Type: research
CONCLUSION: Although cardiac hydatid disease is rare, its prevalence seems to have increased in the last decade. Any patient with suspected cardiac symptoms suggesting mass lesions should be considered for a differential diagnosis of cardiac hydatid disease, especially in developing countries. Definitive treatment is removal of the cyst, combined with medical therapy. PMID: 28218769 [PubMed - as supplied by publisher]
Source: Cardiovascular Journal of Africa - Category: Cardiology Authors: Tags: Cardiovasc J Afr Source Type: research
Intra-abdominal polymicrobial infections cause significant morbidity and mortality. An experimental mouse model of Candida albicans-Staphylococcus aureus intra-abdominal infection (IAI) results in 100% mortality by 48 to 72 h postinoculation, while monomicrobial infections are avirulent. Mortality is associated with robust local and systemic inflammation without a requirement for C. albicans morphogenesis. However, the contribution of virulence factors coregulated during the yeast-to-hypha transition is unknown. This also raised the question of whether other Candida species that are unable to form hyphae are as virulent as...
Source: Infection and Immunity - Category: Infectious Diseases Authors: Tags: Fungal and Parasitic Infections Source Type: research
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