Clinical Management of North American Snake and Marine Envenomations.

Envenomations are the 23rd most common reason for calls to US poison control centers, with over 35,000 incidents reported annually. Snake bites account for over 20% of those calls, while marine envenomations are likely underreported at 3% to 4%.1 While these types of envenomations may not be encountered on a daily basis for many physicians, the different types of envenomations warrant unique management strategies based on the offending creature and symptom presentation. This text serves as a review of the epidemiology, clinical presentations, and management of endemic North American species of snakes and marine vertebrate and invertebrate envenomations.

Fishing Out a Bone From the Neck.

Foreign body ingestion is a common medical issue in Asian populations. Fish bones are the most commonly ingested foreign bodies due to the practice of cooking fish whole with bones intact, unlike in Western countries where fish are typically prepared as fillets or patties. Patients who have swallowed fish bones usually present with foreign body sensations, odynophagia, and pricking sensations during deglutination. Fish bones can generally be removed in an outpatient setting, but in some cases, patients must be placed under general anesthesia, where rigid esophagoscopy is performed. In some cases, neck exploration is required to extricate the bone. Here, we report the case of a 71-year-old man who underwent neck exploration for a 2.1 cm fish bone lateral to his thyroid cartilage, penetrating the left thyroid lobe.

Evaluation of the toxicological properties of Himantura imbricata Venom using a zebrafish model (Danio rerio).

The stingrays of the genus Himantura imbricata are present in all of the world's oceans, but the toxicity of their venoms has not yet been thoroughly characterized. The zebrafish as a toxicology model can be used for general toxicity testing of drugs and the investigation of toxicological mechanisms. The aim of this study was to evaluate the effect of crude venom from the stingray H. imbricata on the zebrafish Danio rerio. Juvenile zebrafish were injected with different concentrations of venom from H. imbricata via subcutaneous injections. The venom's effects were established via histological examination and hemolytic activity in zebrafish. The histopathological analysis revealed significant tissue damage in the organs of the zebrafish injected with venom, including liver necrosis and kidney degeneration. A blood examination revealed echinocytes, hemolysis, and nuclear abnormalities. Bodyweight estimations and histopathological attributes of the gills, heart, muscle, liver, intestine, eye, and brain were determined. The histological staining studies of the gills, liver, and intestine were measurably higher in the venom groups compared with the other two groups. Aggregately, the result shows that zebrafish may act as a valuable biomarker for alterations impelled by H. imbricata venom. The work delivers a useful model with substantial pharmacological potential for new drugs and a better comprehension of research on stingray venom.

Bioactive Properties of Venoms Isolated from Whiptail Stingrays and the Search for Molecular Mechanisms and Targets.

The venom-containing barb attached to their 'whip-like' tail provides stingrays a defensive mechanism for evading predators such as sharks. From human encounters, dermal stingray envenomation is characterized by intense pain often followed by tissue necrosis occurring over several days to weeks. The bioactive components in stingray venoms (SRVs) and their molecular targets and mechanisms that mediate these complex responses are not well understood. Given the utility of venom-derived proteins from other venomous species for biomedical and pharmaceutical applications, we set out to characterize the bioactivity of SRV extracts from three local species that belong to the Dasyatoidea 'whiptail' superfamily. Multiple cell-based assays were used to quantify and compare the in vitro effects of these SRVs on different cell lines. All three SRVs demonstrated concentration-dependent growth-inhibitory effects on three different human cell lines tested. In contrast, a mouse fibrosarcoma cell line was markedly resistant to all three SRVs, indicating the molecular target(s) for mediating the SRV effects are not expressed on these cells. The multifunctional SRV responses were characterized by an acute disruption of cell adhesion leading to apoptosis. These findings aim to guide future investigations of individual SRV proteins and their molecular targets for potential use in biomedical applications.

Effect of photobiomodulation therapy as a multimodal approach to treatment of dermal abrasions in cownose rays (Rhinoptera bonasus).

Photobiomodulation therapy (PBMT) has become increasingly utilized in the zoo and aquarium fields to treat ailments in various species; however, its use in teleosts and elasmobranchs is relatively underrepresented in the literature. This study examined the efficacy of PBMT as an adjunct treatment to reduce the healing time of dermal abrasions in cownose rays (Rhinoptera bonasus). Ten cownose rays were included in this study and separated into control (n = 5) and treatment groups (n = 5). Animals in both treatment and control groups received intramuscular injections of enrofloxacin every 72 h to provide broad-spectrum antibiotic coverage. Cownose rays in the treatment group additionally received PBMT using the Companion® CTC-12 unit using the large, noncontact head. Control group rays were subjected to identical handling without the use of PBMT. A total of 196 Joules were delivered at a power of 2 W based on a dose of 5 J/cm2 at each session. Observational analysis revealed a lack of appreciable difference in healing time between the treatment and control groups in the aforementioned settings; however, it is recommended that PBMT protocols should be re-evaluated if there is little to no response in healing after three to four sessions. PBMT use on acute superficial dermal abrasions in cownose rays was well-tolerated in this study and may have utility in a multimodal treatment approach to wound healing. This study also produced a wound scoring metric based on photographs captured at each treatment. Future studies should utilize increased fluence (J/cm2) and irradiance (W/cm2) and incorporate synchronous histological analysis and increased sample size.

Length-weight relationship for Potamotrygon wallacei (Carvalho, Rosa and Araújo, 2016) caught in the middle Negro River, Barcelos, Brazilian Amazon

Abstract This research aimed to estimate the length-weight ratio (LWR) of the stingray Potamotrygon wallacei, known locally as the cururu, which was caught in streams and lakes in the middle Negro River region, Amazonas, Brazil. The stingrays were captured during the night (from 11 pm to 1 am) near the shores of streams and lakes, through active search using wooden canoes, head lanterns and scoop nets. The samplings were carried out in November 2017 (5 days), February (8 days), March (3 days) and April (2 days) of 2018, totaling 18 days of sampling. The total fresh weight was measured to 0.1 g of accuracy and the disc width to 0.1 cm accuracy. The parameters a and b of the equation W=a.DWb were estimated. This study provides new maximum length data for the cururu stingray.

Resumo Esta pesquisa teve como objetivo estimar a relação peso-comprimento (LWR) da arraia Potamotrygon wallacei, conhecida localmente como cururu, que foi capturada em igarapés e lagos na região do médio Rio Negro, Amazonas, Brasil. As arraias foram capturadas durante a noite (das 23h-1h) nas margens dos igarapés e lagos, por meio de busca ativa utilizando canoas de madeira, lanternas de cabeça e puçás. As coletas foram realizadas nos meses de novembro de 2017 (5 dias), fevereiro (8 dias), março (3 dias) e abril (2 dias) de 2018, totalizando 18 dias de amostragem. Foram medidos o peso fresco total com precisão de 0,01 g e a largura do disco com precisão de 0,1 cm. Os parâmetros a e b da equação W= a.DWb foram estimados. Este estudo prover novos dados de comprimento máximo para a arraia cururu.

Length-weight relationship for Potamotrygon wallacei (Carvalho, Rosa and Araújo, 2016) caught in the middle Negro River, Barcelos, Brazilian Amazon / Relação peso-comprimento de Potamotrygon wallacei (Carvalho, Rosa e Araújo, 2016) capturada no médio Rio Negro, Barcelos, Amazônia Brasileira

Abstract This research aimed to estimate the length-weight ratio (LWR) of the stingray Potamotrygon wallacei, known locally as the cururu, which was caught in streams and lakes in the middle Negro River region, Amazonas, Brazil. The stingrays were captured during the night (from 11 pm to 1 am) near the shores of streams and lakes, through active search using wooden canoes, head lanterns and scoop nets. The samplings were carried out in November 2017 (5 days), February (8 days), March (3 days) and April (2 days) of 2018, totaling 18 days of sampling. The total fresh weight was measured to 0.1 g of accuracy and the disc width to 0.1 cm accuracy. The parameters a and b of the equation W=a.DWb were estimated. This study provides new maximum length data for the cururu stingray.

Resumo Esta pesquisa teve como objetivo estimar a relação peso-comprimento (LWR) da arraia Potamotrygon wallacei, conhecida localmente como cururu, que foi capturada em igarapés e lagos na região do médio Rio Negro, Amazonas, Brasil. As arraias foram capturadas durante a noite (das 23h-1h) nas margens dos igarapés e lagos, por meio de busca ativa utilizando canoas de madeira, lanternas de cabeça e puçás. As coletas foram realizadas nos meses de novembro de 2017 (5 dias), fevereiro (8 dias), março (3 dias) e abril (2 dias) de 2018, totalizando 18 dias de amostragem. Foram medidos o peso fresco total com precisão de 0,01 g e a largura do disco com precisão de 0,1 cm. Os parâmetros a e b da equação W= a.DWb foram estimados. Este estudo prover novos dados de comprimento máximo para a arraia cururu.

Estudo da toxicidade das peçonhas da arraia Potamotrygon leopoldi em embriões de Zebrafish

Among aquatic animals, there are some species of venomous fish that represent a public health problem, including freshwater stingrays. Accidents involving these animals result in local pain, edema, tissue necrosis, tissue laceration caused by the sting with serrated edges and the risk of the clinical condition developing into a serious infection due to exposure to bacteria. In the Xingu River basin, accidents involving freshwater stingrays are common, especially with the species Potamotrygon leopoldi, whose defense apparatus is a stinger and spines on its tail. As this is an understudied species whose accidents occur in a region far from large urban centers, they are underreported and often do not receive adequate treatment. Therefore, the aim of this study was to evaluate the venom toxicity present in the sting and spines of adult P. leopoldi of both genera. The samples were collected in the Xingu River basin in the state of Pará, stored in 50 mL Falcon tubes containing PBS, kept under refrigeration and transported to the Applied Toxinology Laboratory at the Butantan Institute. After epithelial scraping of the sting and maceration of spines, we used the Bradford technique to quantify the proteins, electrophoresis to identify the protein profile and the acute toxicity test on zebrafish embryos to determine the lethal and sublethal toxicity parameters after the exposition to 6.25, 25, and 50 μg of protein. The results showed a variation in the amount of stings protein between males and females, with 2.93 mg/mL and 1.91 mg/mL, respectively; this was also reproduced in the protein values of the spines, 7.71 for the female samples and 12.27 mg/mL for the males. The electrophoretic profile of the proteins did not differ significantly between the groups; however, it was complex with around 8-12 bands distributed between 198 and 6 kDa. With regard to the toxicity test, we found a low mortality rate at low doses, where the groups exposed to both the sting and thorn toxins did not exceed 20% mortality. When the dose was increased, mortality and teratogenicity were high, especially the female spines at the dose of 25 μg. We can conclude that the proteins in the spines of both genera stand out compared to the stingers. However, the results of the toxicity test suggested that the toxin from the stingers is more toxic compared to the spines, except at a dose of 25 μg, where it caused greater toxic effects on the zebrafish embryos.

Dentre os animais aquáticos existem algumas espécies de peixes peçonhentos que representam um problema de saúde pública, dentre eles destacam-se as arraias de água doce. Os acidentes com esses animais resultam em dor local, edema, necrose tecidual, dilaceração do tecido causada pelo ferrão com bordas serrilhadas e risco de evoluir o quadro clínico para uma infecção grave devido a exposição a bactérias. Na bacia do rio Xingu os acidentes com arraias de água doce são comuns, em especial com a espécie Potamotrygon leopoldi, que apresenta como aparato de defesa ferrão e espinhos na cauda. Por se tratar de uma espécie pouco estudada e cujos acidentes acontecem em uma região afastada de grandes centros urbanos, estes são subnotificados e comumente não recebem um tratamento adequado. Dessa forma, este trabalho tem como objetivo avaliar a toxicidade da peçonha presente no ferrão e espinhos da espécie P. leopoldi adulta de ambos os gêneros. As amostras foram coletadas na bacia do rio Xingu no estado do Pará, armazenadas em tubos Falcon de 50 mL contendo PBS, mantidos sob refrigeração e transportados até o Laboratório de Toxinologia Aplicada do Instituto Butantan. Após a raspagem epitelial do ferrão e maceração dos espinhos, utilizamos a técnica de Bradford para quantificar as proteínas, eletroforese a fim de identificar o perfil proteico e o teste de toxicidade aguda em embriões de zebrafish para determinar os parâmetros letais e subletais de toxicidade após a exposição de concentrações de 6,25, 25 e 50 μg. Os resultados destacaram uma variação na quantidade de proteínas dos ferrões entre machos e fêmeas, sendo 2,93 mg/mL e 1,91 mg/mL, respectivamente; o que também se reproduz nos valores proteicos dos espinhos, 7,71 para as amostras de fêmeas e 12,27 mg/mL para os machos. O perfil eletroforético das proteínas não divergiu expressivamente entre os grupos; no entanto, demonstrou-se complexo com cerca de 8-12 bandas distribuídas entre 198 a 6 kDa. Com relação ao teste de toxicidade verificamos baixa taxa de mortalidade em menores doses, onde os grupos expostos tanto a peçonha do ferrão quanto a do espinho não ultrapassaram 20% de mortalidade. Ao aumentar a dose, a mortalidade e teratogenicidade tiveram índices altos, em destaque o espinho das fêmeas na dose de 25 μg. Podemos concluir que as proteínas dos espinhos de ambos os gêneros se sobressaem em comparação aos ferrões. Porém, os resultados do teste de toxicidade sugerem que a peçonha dos ferrões é mais tóxica em comparação aos espinhos, exceto na dose de 25 μg, onde causaram maiores efeitos tóxicos nos embriões de zebrafish.

Accuracy of Emergency Medicine Residents Using Point-of-Care Ultrasound (POCUS) to Detect Retained Stingray Barbs.

BACKGROUND: Stingray envenomation is a common presenting complaint for coastal emergency departments in the United States. Currently, radiograph is the gold standard to evaluate for a retained stingray barb, but ultrasound may be a useful tool to detect retained barbs. OBJECTIVE: To determine if emergency medicine residents could use ultrasound to identify stingray barbs embedded in animal tissue models. A secondary objective was to determine if resident experience affected their ability to detect stingray barbs. METHODS: Thirty-two emergency medicine residents participated in the study. After a short didactic session on foreign body identification with ultrasound, they rotated through six simulation stations and were asked to identify whether a stingray barb was present in pig and chicken tissue models. They were given 2 min per model to identify the presence, size, and depth of a stingray barb. Pre- and postexperiment surveys were collected to assess the residents' level of experience and confidence regarding foreign body identification using ultrasound. RESULTS: Residents accurately identified barbs in chicken drumsticks with a sensitivity of 72.92% (95% confidence interval [CI] 63.89-81.48) and a specificity of 64.58% (95% CI 54.16-74.08), and in pig's feet with a sensitivity of 50.00% (95% CI 39.62-60.38) and specificity of 68.75% (95% CI 58.48-77.82). There was no statistically significant difference regarding accuracy for any outcome measured based on experience or level of training. CONCLUSIONS: The use of point-of-care ultrasound by novice sonographers lacks sensitivity to identify retained stingray barbs in animal models and is not significantly impacted by resident experience with point-of-care ultrasound.

Exploring indicators of success in chronic total occlusion percutaneous coronary intervention with Stingray system-based antegrade dissection re-entry: Insights from retrospective analysis.

BACKGROUND: The predictors of success of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) through antegrade dissection and re-entry (ADR) using the Stingray system (Stingray ADR) remain elusive, mainly owing to the lack of consecutive angiographic and procedural records of patients. OBJECTIVES: This study aimed to identify indicators that can determine the success of CTO PCI performed using the Stingray ADR technique. METHODS: The clinical data of 115 patients who underwent CTO PCI through Stingray ADR at the same cardiac center were retrospectively and consecutively collected. Multivariate logistic regression analysis was performed to investigate the indicators of the success of ADR attempts. RESULTS: The technical success rate of Stingray ADR in CTO PCI was 72.2%. The overall technical success rate of CTO recanalization was 78.3% in all CTO PCIs having used Stingray Low Profile balloon. Vessel calcification (odds ratio [OR]: 4.03; 95% confidence interval [CI]: 1.49-11.88; p = 0.008), and retrograde puncture indicator (OR: 4.89; 95% CI: 1.51-17.11; p = 0.009) were identified as independent positive predictors. Blunt/no stump proximal to the occlusion segment (OR: 0.22; 95% CI: 0.06-0.64; p = 0.009), decision time before Stingray ADR (per 1 h increase) (OR: 0.54; 95% CI: 0.31-0.92; p = 0.026), operation duration of Stingray ADR (per 10 min increase) (OR: 0.62; 95% CI: 0.40-0.94; p = 0.028), and puncture site at the intraplaque region (OR: 0.24; 95% CI: 0.06-0.84; p = 0.026) were identified as the four negative independent predictors. CONCLUSIONS: This study revealed independent predictors of the success of CTO PCI performed using the Stingray ADR technique. As for CTO characteristics, the presence of calcification in the CTO segment and a tapered stump proximal to the lesion site can facilitate successful Stingray ADR. As for the procedures, the success rate of Stingray ADR can be improved by initiating the technique decisively and promptly, operating the system quickly and accurately and creating a puncture in the distal cap region of CTO under retrograde guidance.

A Novel Parallel Wire-based Antegrade Dissection Re-entry Technique for Failed Retrograde Attempt of Coronary Chronic Total Occlusions with Risk Nomogram Analysis.

BACKGROUND: Rapid development in coronary chronic total occlusion (CTO) interventional techniques and devices have achieved a greater success rate with favorable outcomes. Antegrade dissection re-entry (ADR) technique is an important CTO crossing strategy and a desirable approach for long CTOs with good distal landing zone. However, unsuccessful procedures in contemporary CTO-percutaneous coronary intervention (PCI) remain, especially in lesions with non-interventional collaterals. METHOD: Based on a single center experience, a hybrid interventional algorithm, parallel wire-based ADR (PW-ADR) combines the advantages of parallel wire technique (PWT) and device-based ADR to target CTO lesions with failed retrograde approach. A retrospective analysis of patients who underwent PW-ADR was performed. A risk nomogram was created to identify patients at high risk for technical failure. RESULTS: A total of 57 patients treated with PW-ADR were ultimately included in the present study. A total of 46 (80.7%) cases achieved technical success and procedural success, with low incidence of in-hospital complications or 1-year major adverse cardiac events (MACE). The risk nomogram identified 3 predictor variables associated with technical failure of PW-ADR, including tortuous vessel, J-CTO score, and times of antegrade coronary angiography (CAG) during ADR, with promising accuracy (AUROC 0.947). CONCLUSION: The novel hybrid CTO-PCI algorithm, PW-ADR, provided an alternative interventional approach for complex CTO lesions with a promising success rate. The risk nomogram served as a prompter for high-risk cases, which may warrant a change in treatment strategy.

The present study reported a new hybrid-PCI strategy with a promising success rate for the treatment of CTO from a single center experience, over last 5 years. A retrospective analysis of patients who underwent PW-ADR was performed. A risk nomogram was created to identify patients at high risk for technical failure. 80.7% of patients treated with PW-ADR were achieved technical success and procedural success, with low incidence of in-hospital complications or 1-year MACE in the present study. A total of 3 predictor variables were identified to be associated with technical failure of PW-ADR, including tortuous vessel, J-CTO score, and times of antegrade CAG during ADR. This prediction tool may allow early identification of more complex and difficult CTO cases that require a timely switch in strategic approach or termination of the procedure to avoid unnecessary surgical risk.

The evolutionary origin of the durophagous pelagic stingray ecomorph.

Studies of the origin of evolutionary novelties (novel traits, feeding modes, behaviours, ecological niches, etc.) have considered a number of taxa experimenting with new body plans, allowing them to occupy new habitats and exploit new trophic resources. In the marine realm, colonization of pelagic environments by marine fishes occurred recurrently through time. Stingrays (Myliobatiformes) are a diverse clade of batoid fishes commonly known to possess venomous tail stings. Current hypotheses suggest that stingrays experimented with a transition from a benthic to a pelagic/benthopelagic habitat coupled with a transition from a non-durophagous diet to extreme durophagy. However, there is no study detailing macroevolutionary patterns to understand how and when habitat shift and feeding specialization arose along their evolutionary history. A new exquisitely preserved fossil stingray from the Eocene Konservat-Lagerstätte of Bolca (Italy) exhibits a unique mosaic of plesiomorphic features of the rajobenthic ecomorph, and derived traits of aquilopelagic taxa, that helps to clarify the evolutionary origin of durophagy and pelagic lifestyle in stingrays. A scenario of early evolution of the aquilopelagic ecomorph is proposed based on new data, and the possible adaptive meaning of the observed evolutionary changes is discussed. The body plan of †Dasyomyliobatis thomyorkei gen. et sp. nov. is intermediate between the rajobenthic and more derived aquilopelagic stingrays, supporting its stem phylogenetic position and the hypothesis that the aquilopelagic body plan arose in association with the evolution of durophagy and pelagic lifestyle from a benthic, soft-prey feeder ancestor.

Characterization of Some Dermato-Cosmetic Preparations with Marine Lipids from Black Sea Wild Stingray.

The traditional knowledge about the therapeutic and nutritional value of fish has been unanimously recognized among the population since ancient times. So, thanks to the therapeutic virtues of these marine animals, it was possible to develop therapies for certain pathologies as well as the use of bioactive compounds as adjunctive therapies incorporated into the treatment regimen of patients. In the present study, stingray liver oil from wild species collected from the Romanian coast of the Black Sea was isolated and analyzed. Fatty acid analysis was performed by gas chromatography. The analysis of the distribution of fatty acids in the composition of stingray liver oil indicates a ratio of 2.83 of omega 3 fatty acids to omega 6, a ratio of 1.33 of polyunsaturated fatty acids to monounsaturated fatty acids, an iodine index of 111.85, and a total percentage of 68.98% of unsaturated fatty acids. Stingray liver oil was used to evaluate the healing action after preparing a fatty ointment. According to the experimental data, a complete regeneration capacity of the wounds was noted in 12 days without visible signs. Four emulgels with stingray liver oil were formulated and analyzed from a rheological and structural point of view in order to select the optimal composition, after which the anti-inflammatory effect on inflammation caused in laboratory rats was studied and an anti-inflammatory effect was found significant (a maximum inhibitory effect of 66.47% on the edemas induced by the 10% kaolin suspension and 65.64% on the edemas induced by the 6% dextran solution).

Venomous Bites, Stings and Poisoning by European Vertebrates as an Overlooked and Emerging Medical Problem: Recognition, Clinical Aspects and Therapeutic Management.

Europe presents a high number of venomous and poisonous animals able to elicit medically relevant symptoms in humans. However, since most of the accidents involving venomous or poisonous animals in Europe are unreported, their incidence and morbidity are severely overlooked. Here we provide an overview of the European vertebrate species of greatest toxicological interest, the clinical manifestations their toxins can cause, and their treatment. We report the clinical symptoms induced by envenomations and poisoning caused by reptiles, fishes, amphibians and mammals in Europe, ranging from mild, local symptoms (e.g., erythema, edema) to systemic and potentially deadly. The present work constitutes a tool for physicians to recognize envenomation/poisoning symptoms caused by the most medically relevant European vertebrates and to decide which approach is the most appropriate to treat them.

Stingray Envenomation: Consequences of an Embedded Spine.

Rays and skates are fish with flattened, pancake-shaped bodies that frequent shallow water, where they often lie hidden under the sand. Some of the batoid species are characterized by a stinger with serrated edges, which is covered by a tegument made up of specialized cells that secrete toxins and enzymes with proteolytic activity. Stingray injuries to humans are common in warm coastal regions. In this report, we present a case of an injury due to the insertion of a barb from a Pacific cownose ray, Rhinoptera steindachneri. We assess the tissue complications due to the retention of the spine in the foot, the subsequent infection that caused tissue necrosis, and the reconstructive surgery performed. Based on previous experience, we highly recommend performing diagnostic procedures such as soft tissue radiographs and MRI to ensure the absence of the barb within the wound and thereby avoid further complications. Current textbook treatment is based on limited scientific studies, case reports, and successful clinical treatment of many victims.

Management of a stingray barb laceration and suspect envenomation in a dog.

This case report describes the successful management of a stingray laceration and suspected envenomation using a combination of opioid analgesia, heat compression, antimicrobial therapy, surgical debridement and closure. Stingray envenomation in the dog is a rare clinical presentation and is yet to be documented in the Australian veterinary literature. Envenomation can be markedly painful and may cause swelling and local tissue necrosis. No consensus on treatment guidelines has been published. Diagnostics and treatments performed are outlined with recommendations on a management plan for future cases.

Stingray epidermal microbiomes are species-specific with local adaptations.

Marine host-associated microbiomes are affected by a combination of species-specific (e.g., host ancestry, genotype) and habitat-specific features (e.g., environmental physiochemistry and microbial biogeography). The stingray epidermis provides a gradient of characteristics from high dermal denticles coverage with low mucus to reduce dermal denticles and high levels of mucus. Here we investigate the effects of host phylogeny and habitat by comparing the epidermal microbiomes of Myliobatis californica (bat rays) with a mucus rich epidermis, and Urobatis halleri (round rays) with a mucus reduced epidermis from two locations, Los Angeles and San Diego, California (a 150 km distance). We found that host microbiomes are species-specific and distinct from the water column, however composition of M. californica microbiomes showed more variability between individuals compared to U. halleri. The variability in the microbiome of M. californica caused the microbial taxa to be similar across locations, while U. halleri microbiomes were distinct across locations. Despite taxonomic differences, Shannon diversity is the same across the two locations in U. halleri microbiomes suggesting the taxonomic composition are locally adapted, but diversity is maintained by the host. Myliobatis californica and U. halleri microbiomes maintain functional similarity across Los Angeles and San Diego and each ray showed several unique functional genes. Myliobatis californica has a greater relative abundance of RNA Polymerase III-like genes in the microbiome than U. halleri, suggesting specific adaptations to a heavy mucus environment. Construction of Metagenome Assembled Genomes (MAGs) identified novel microbial species within Rhodobacteraceae, Moraxellaceae, Caulobacteraceae, Alcanivoracaceae and Gammaproteobacteria. All MAGs had a high abundance of active RNA processing genes, heavy metal, and antibiotic resistant genes, suggesting the stingray mucus supports high microbial growth rates, which may drive high levels of competition within the microbiomes increasing the antimicrobial properties of the microbes.

The first record of gravid spiny butterfly ray (Gymnura altavela) in the northern Mediterranean Sea, with description of near-term foetuses.

This paper describes the first record of the critically endangered gravid female spiny butterfly ray, Gymnura altavela (Linnaeus, 1758), in the northern Mediterranean and simultaneously the only record of the species in this century for the Adriatic Sea. The female (173 cm disc width and 43.25 kg total weight) was captured at c. 200 m, off Vlorë in the southern Adriatic Sea off Albania on 12 May 2022. Upon necropsy, seven near-term foetuses (mean 328 ± 6.47 mm disc width and mean 355 ± 20.06 g in total weight) were transported for further in-vitro incubation. These results represent the deepest capture for the species, as well as the largest litter size and largest size at birth in the Mediterranean Sea, which indicates the need for further research.

The seven day itch: A delayed histamine reaction to stingray injury.

Stingray injuries are common presentations to emergency departments near warm coastal waters. Commonly reported injuries include puncture wounds, lacerations, and envenomations, the latter of which cause severe pain but are usually easily treated with warm water immersion. We report a case of delayed histamine reaction in a patient who sustained a stingray envenomation one week prior which we believe is the first such report in the medical literature but is found on discussion boards for those who have sustained stingray injuries. The literature on such envenomations is reviewed.

Preparation and evaluation of stingray skin collagen/oyster osteoinductive composite scaffolds.

The regeneration of bone defects is a major challenge for clinical orthopaedics. Herein, we designed and prepared a new type of bioactive material, using stingray skin collagen and oyster shell powder (OSP) as raw materials. A stingray skin collagen/oyster osteoinductive composite scaffold (Col-OSP) was prepared for the first time by genipin cross-linking, pore-forming and freeze-drying methods. These scaffolds were characterized by ATR-FTIR, SEM, compression, swelling, cell proliferation, cell adhesion, alkaline phosphatase activity, alizarin red staining and RT-PCR etc. The Col-OSP scaffold had an interconnected three-dimensional porous structure, and the mechanical properties of the Col-OSP composite scaffold were enhanced compared with Col, combining with the appropriate swelling rate and degradation rate, the scaffold was more in line with the requirements of bone tissue engineering scaffolds. The Col-OSP scaffold was non-toxic, promoted the proliferation, adhesion, and differentiation of MC3T3-E1 cells, and stimulated the osteogenesis-related genes expressions of osteocalcin (OCN), collagen type I (COL-I) and RUNX2 of MC3T3-E1 cells.