Effects of exercise induced muscle damage on cardiovascular responses to isometric muscle contractions and post-exercise circulatory occlusion

Purpose: The aim of the present study was to investigate whether exercise-induced muscle damage (EIMD) influences cardiovascular responses to isometric exercise and post-exercise circulatory occlusion (PECO). We hypothesized that EIMD would increase muscle afferent sensitivity and, accordingly, increase blood pressure responses to exercise and PECO. Methods: Eleven male and nine female participants performed unilateral isometric knee extension at 30% of maximal voluntary contraction (MVC) for 3-min. A thigh cuff was rapidly inflated to 250 mmHg for two min PECO, followed by 3 min recovery. Heart rate and blood pressure were monitored beat-by-beat, with stroke volume and cardiac output estimated from the Modelflow algorithm. Measurements were taken before and 48 h after completing eccentric knee-extension contractions to induce muscle damage (EIMD). Results: EIMD caused 21% decrease in MVC (baseline: 634.6 ± 229.3 N, 48 h: 504.0 ± 160 N), and a 17-fold increase in perceived soreness using a visual-analogue scale (0–100 mm; VASSQ) (both p < 0.001). CV responses to exercise and PECO were not different between pre and post EIMD. However, mean arterial pressure (MAP) was higher during the recovery phase after EIMD (p < 0.05). Significant associations were found between increases in MAP during exercise and VASSQ, Rate of Perceived Exertion (RPE) and Pain after EIMD only (all p < 0.05). Conclusion: The MAP correlations with muscle soreness, RPE and Pain during contractions of damaged muscles suggests that higher afferent activity was associated with higher MAP responses to exercise

Origin and main ramifications of coeliac artery in Cerdocyon thous

Background: Cerdocyon thous is the canid with the greatest geographical coverage in South America. The aim of this study was to describe the origin, skeletopy, length and main branches of the coeliac artery in C. thous. Materials and methods: The dissections were performed on 14 cadavers of adult specimens, 6 males and 8 females, with a rostrosacral length average of 67.00 ± 4.7 cm and 62.09 ± 5.7 cm, respectively. The specimens were collected dead on highways on the banks of the Atlantic Forest (Rio de Janeiro) and the Pampa biome (Rio Grande do Sul) in Brazil. The cadavers were fixed and preserved in a formaldehyde solution until dissection. The coeliac artery was dissected, the length was measured “in situ” and its main branches were recorded. The coeliac artery emerged as a single artery in all dissected animals. Results: The average length of the coeliac artery was 1.43 ± 0.17 cm in males and 1.39 mm ± 0.24 cm in females, with no significant difference in this measurement between sexes. The predominant skeletopy was at the level of the second lumbar vertebra (57.1%), positioned on average 1.43 cm cranially to the cranial mesenteric artery. In most individuals (92.9%), the classic trifurcation was formed: the coeliac artery branched into the hepatic, left gastric, and lienal arteries. Only 1 male animal presented a bifurcation formed between the hepatic artery and a gastrolienal trunk. Conclusions: These anatomical characteristics are similar to those of other species of the Canidae family, possibly due to their phylogenetic proximity

Anatomical characterisation of the kidneys of Didelphis aurita (Didelphimorphia: Didelphidae)

Background: Didelphis aurita is a marsupial with wide distribution in the South American continent and highly adapted to urban centres. The objective of this study was to describe the measurements and skeletopy of the kidneys and renal vascularisation of this species.Materials and methods: With this aim, 29 cadavers (14 males and 15 females) of D. aurita collected on highways were analysed. The rostrum-sacral length of specimens, kidney measurements (length, width and thickness) and the length of the renal vessels were measured and the renal skeletopy registered.Results: In the right kidney, average length, width, thickness and ellipsoid volume were 28.6 ± 5.0 mm, 15.6 ± 2.9 mm, 12.8 ± 3.0 mm and 3.3 ± 2.4 cm3, respectively; in the left kidney, 31.0 ± 3.8 mm, 14.5 ± 3.6 mm, 12.6 ± 2.6 mm and 3.2 ± 2.2 cm3, respectively. There was no significant difference in the comparison of averages of renal dimensions between sexes and between antimeres. The right renal artery (13.2 ± 2.6 mm) was significantly longer (p &lt; 0.01) than the left renal artery (10.7 ± 2.3 mm). In contrast, the left renal vein (13.9 ± 3.5 mm) was longer (p &lt; 0.01) than the right renal vein (7.0 ± 2.3 mm). The skeletopy of the right kidney predominated between T13–L1 in 58.6% of the cases and the skeletopy of the left kidney between L1–L3 in 41.4%. The average length of the kidneys corresponded to 6% to 8% of the rostrum-sacral length of the specimens.Conclusions: The data of the present study characterised the measurements and topography of kidneys and renal vessels in D. aurita and can support the interpretation of clinical, experimental and pathological findings in this species

Photobiomodulation reduces the cytokine storm syndrome associated with Covid-19 in the zebrafish model

Although the exact mechanism of the pathogenesis of COVID-19 is not fully understood, oxidative stress and the release of pro-inflammatory cytokines have been highlighted as playing a vital role in the pathogenesis of the disease. In this sense, alternative treatments are needed to reduce the inflammation caused by COVID-19. Therefore, this study aimed to investigate the potential effect of red PBM as an attractive therapy to downregulate the cytokine storm caused by COVID-19 from a zebrafish model. RT-PCR analyses and protein-protein interaction prediction among SARS-CoV-2 and Danio rerio proteins showed that rSpike was responsible for generating systemic inflammatory processes with significantly increased pro-inflammatory (il1b, il6, tnfa, and nfkbiab), oxidative stress (romo1) and energy metabolism (slc2a1a, coa1) mRNA markers, with a pattern like those observed in COVID-19 cases in humans. On the other hand, PBM treatment decreased the mRNA levels of these pro-inflammatory and oxidative stress markers compared with rSpike in various tissues, promoting an anti-inflammatory response. Conversely, PBM promotes cellular and tissue repair of injured tissues and significantly increases the survival rate of rSpike-inoculated individuals. Additionally, metabolomics analysis showed that the most impacted metabolic pathways between PBM and the rSpike-treated groups were related to steroid metabolism, immune system, and lipids metabolism. Together, our findings suggest that the inflammatory process is an incisive feature of COVID-19, and red PBM can be used as a novel therapeutic agent for COVID-19 by regulating the inflammatory response. Nevertheless, the need for more clinical trials remains, and there is a significant gap to overcome before clinical trials.publishedVersio

Tegumentary leishmaniasis and coinfections other than HIV

<div><p>Background</p><p>Tegumentary leishmaniasis (TL) is a disease of skin and/or mucosal tissues caused by <i>Leishmania</i> parasites. TL patients may concurrently carry other pathogens, which may influence the clinical outcome of TL.</p><p>Methodology and principal findings</p><p>This review focuses on the frequency of TL coinfections in human populations, interactions between <i>Leishmania</i> and other pathogens in animal models and human subjects, and implications of TL coinfections for clinical practice. For the purpose of this review, TL is defined as all forms of cutaneous (localised, disseminated, or diffuse) and mucocutaneous leishmaniasis. Human immunodeficiency virus (HIV) coinfection, superinfection with skin bacteria, and skin manifestations of visceral leishmaniasis are not included. We searched MEDLINE and other databases and included 73 records: 21 experimental studies in animals and 52 studies about human subjects (mainly cross-sectional and case studies). Several reports describe the frequency of <i>Trypanosoma cruzi</i> coinfection in TL patients in Argentina (about 41%) and the frequency of helminthiasis in TL patients in Brazil (15% to 88%). Different hypotheses have been explored about mechanisms of interaction between different microorganisms, but no clear answers emerge. Such interactions may involve innate immunity coupled with regulatory networks that affect quality and quantity of acquired immune responses. Diagnostic problems may occur when concurrent infections cause similar lesions (e.g., TL and leprosy), when different pathogens are present in the same lesions (e.g., <i>Leishmania</i> and <i>Sporothrix schenckii</i>), or when similarities between phylogenetically close pathogens affect accuracy of diagnostic tests (e.g., serology for leishmaniasis and Chagas disease). Some coinfections (e.g., helminthiasis) appear to reduce the effectiveness of antileishmanial treatment, and drug combinations may cause cumulative adverse effects.</p><p>Conclusions and significance</p><p>In patients with TL, coinfection is frequent, it can lead to diagnostic errors and delays, and it can influence the effectiveness and safety of treatment. More research is needed to unravel how coinfections interfere with the pathogenesis of TL.</p></div

Climatic and topographic changes since the Miocene influenced the diversification and biogeography of the tent tortoise (Psammobates tentorius) species complex in Southern Africa

Background: Climatic and topographic changes function as key drivers in shaping genetic structure and cladogenic radiation in many organisms. Southern Africa has an exceptionally diverse tortoise fauna, harbouring one-third of the world’s tortoise genera. The distribution of Psammobates tentorius (Kuhl, 1820) covers two of the 25 biodiversity hotspots in the world, the Succulent Karoo and Cape Floristic Region. The highly diverged P. tentorius represents an excellent model species for exploring biogeographic and radiation patterns of reptiles in Southern Africa. Results: We investigated genetic structure and radiation patterns against temporal and spatial dimensions since the Miocene in the Psammobates tentorius species complex, using multiple types of DNA markers and niche modelling analyses. Cladogenesis in P. tentorius started in the late Miocene (11.63–5.33 Ma) when populations dispersed from north to south to form two geographically isolated groups. The northern group diverged into a clade north of the Orange River (OR), followed by the splitting of the group south of the OR into a western and an interior clade. The latter divergence corresponded to the intensifcation of the cold Benguela current, which caused western aridifcation and rainfall seasonality. In the south, tectonic uplift and subsequent exhumation, together with climatic fuctuations seemed responsible for radiations among the four southern clades since the late Miocene. We found that each clade occurred in a habitat shaped by diferent climatic parameters, and that the niches difered substantially among the clades of the northern group but were similar among clades of the southern group. Conclusion: Climatic shifts, and biome and geographic changes were possibly the three major driving forces shaping cladogenesis and genetic structure in Southern African tortoise species. Our results revealed that the cladogenesis of the P. tentorius species complex was probably shaped by environmental cooling, biome shifts and topographic uplift in Southern Africa since the late Miocene. The Last Glacial Maximum (LGM) may have impacted the distribution of P. tentorius substantially. We found the taxonomic diversify of the P. tentorius species complex to be highest in the Greater Cape Floristic Region. All seven clades discovered warrant conservation attention, particularly Ptt-B–Ptr, Ptt-A and Pv-