Genomic and transcriptomic analyses reveal the adaptation to semi-aquatic and aquatic life in spiders

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  Genomic and transcriptomic analyses reveal the adaptation to semi-aquatic and aquatic life in spiders Abstract Spiders are largely terrestrial, but some lineages have independently adapted to marine and freshwater habitats. Although physiological and behavioral traits supporting these evolutionary transitions have been characterized, the genomic basis of adaptation to aquatic and semi-aquatic habitats in spiders remains unclear. Here, we report a chromosome-level genome assembly for the aquatic spider Argyroneta aquatica. Comparative analysis of 22 spider species supports two independent transitions in semi-aquatic (∼56 Mya) and aquatic (∼44 Mya) lineages. The aquatic spider show distinct respiratory morphology compared with terrestrial spiders, including anterior spiracles and denser tracheoles. Molecular evolution analyses identified lineage-specific shifts in selective constraint or evidence of positive selection linked to trachea development (e.g., Wnt-1, Catenin beta, TMEM23...

Fibrinogen supplementation enhances antivenom efficacy in treating coagulopathy due to hemotoxic snakebite envenoming by Trimeresurus and Agkistrodon species in Yunnan, China

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By Rushen - Trimeresurus hageni, Hagen's pit viper (male) - Bang Lang National Park, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=110226136

Fibrinogen supplementation enhances antivenom efficacy in treating coagulopathy due to hemotoxic snakebite envenoming by Trimeresurus and Agkistrodon species in Yunnan, China

Background: Timely administration of antivenom remains the cornerstone of treatment for hemotoxic snakebite envenoming, primarily aimed at neutralizing circulating toxins and halting the progression of venom-induced consumption coagulopathy (VICC), thus facilitating gradual recovery of the hemostatic system. However, immediate access to antivenom is not always possible, and variations in venom composition among snake species, along with individual patient differences, can result in significant morbidity (including persistent complications of coagulopathy) and mortality.

Methods: This retrospective study evaluated 116 cases of hemotoxic snakebite envenoming caused by Trimeresurus stejnegeri, T. mucrosquamatus, and Agkistrodon halys at three hospitals in Yunnan Province, China (The First People's Hospital of Yunnan Province 63 cases, The People's Hospital of Linxiang District 28 cases, and The First People's Hospital of Xuanwei City 25 cases). Among these, thirty-three patients consented to receive adjunctive therapy with fibrinogen (Fg) in addition to standard antivenom treatment (Agkistrodon acutus antivenom or Agkistrodon halys antivenom), while the remaining 83 received antivenom alone. Coagulation parameters were measured at admission and discharge. Statistical analyses were performed using IBM SPSS Statistics and GraphPad Prism, employing the Mann-Whitney U test for non-normally distributed data and Student's t-test for normally distributed data.

Results: In the antivenom-only group, significant reductions were observed in prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (APTT), and D-dimer (DD2) levels (all P < 0.05), accompanied by increases in Fg and fibrin degradation products (FDP; P < 0.05). Patients receiving the combined regimen demonstrated decreases in PT, INR, thrombin time (TT), APTT, FDP, and DD2 (all P < 0.05), along with a significant rise in Fg levels (P < 0.05). Those who received Fg presented with more severe coagulation deficits at baseline. Despite this, by the time of discharge, the median Fg level in the combination group [1.94 (1.52–2.20) g/L] was significantly higher than in the antivenom-only group [0.84 (0.68–1.17) g/L] (P < 0.0001), and closer to the physiological range (2–4 g/L). Moreover, the hospital stay in the combination group (4.88 ± 1.47 days) was significantly shorter than in the antivenom-only group (7.07 ± 2.02 days; P < 0.0001).

Conclusions: These findings suggest that adjunctive Fg supplementation may improve the laboratory parameters of coagulopathy and reduce the length of hospital stay in hemotoxic snakebite envenoming. However, further clinical evaluations are needed to support the use of Fg as an adjuvant in the management of hemotoxic snakebite envenoming.

Gao, Q., Wang, Y., Teng, Y., Huang, Q., Wang, Y., Feng, S., Han, B., & Li, Z. (2025). Fibrinogen supplementation enhances antivenom efficacy in treating coagulopathy due to hemotoxic snakebite envenoming by Trimeresurus and Agkistrodon species in Yunnan, China. Frontiers in Medicine, 12, 1667800. https://doi.org/10.3389/fmed.2025.1667800