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Spinal dural arteriovenous fistulas (SDAVF) are a subtype of spinal arteriovenous malformation (AVM). Although rare, SDAVF are the most common spinal vascular malformations and have potential devastating neurologic consequences, sometimes irreversible. Originally, they were treated with surgery alone, however endovascular treatment of SDAVF has evolved recently with good results and the understanding of the anatomy plays a key role. The feeder vessel of the AV shunt is supplied by the radiculomedullary or radiculopial artery, the shunt is usually located within the root sleeve of the dura and the SDAVF is drained by the medullary vein via retrograde flow. Generally the endovascular approach uses the catheterization of the segmental arteries; however, aortic thoracolumbar aneurysms can render endovascular access difficult and risky. We present a case where an SDAVF in woman with aneurysmal dilation of the descending aorta and a mural thrombus was successfully treated through percutaneous catheterization of intercostal artery.

Aim: We aimed to describe the neurosonological findings related to cerebral hemodynamics acquired using transcranial Doppler and to determine the frequency of elevated ICP by optic nerve sheath diameter (ONSD) measurement in patients with severe coronavirus disease (COVID-19) hospitalized in the intensive care unit of a national referral hospital in Peru. Methods: We included a retrospective cohort of adult patients hospitalized with severe COVID-19 and acute respiratory failure within the first 7 days of mechanical ventilation under deep sedoanalgesia, with or without neuromuscular blockade who underwent ocular ultrasound and transcranial Doppler. We determine the frequency of elevated ICP bymeasuring the diameter of the optic nerve sheath, choosing as best cut-off value a diameter equal to or >5.8mm. We also determine the frequency of sonographic patterns obtained by transcranial Doppler. Through insonation of the middle cerebral artery. Likewise, we evaluated the associations of clinical, mechanical ventilator, and arterial blood gas variables with ONSD =5.8mm and pulsatility index (PI) =1.1. We also evaluated the associations of hemodynamic findings and ONSD with mortality the effect size was estimated using Poisson regression models with robust variance. Results: This study included 142 patients. The mean age was 51.39 ± 13.3 years, and 78.9% of patients were male. Vasopressors were used in 45.1% of patients, and mean arterial pressure was 81.87 ± 10.64 mmHg. The mean partial pressure of carbon dioxide (PaCO2) was elevated (54.08 ± 16.01 mmHg). Elevated intracranial pressure was seen in 83.1% of patients, as estimated based on ONSD =5.8mm. A mortality rate of 16.2% was reported. In the multivariate analysis, age was associated with elevated ONSD (risk ratio [RR] = 1.07). PaCO2 was a protective factor (RR = 0.64) in the cases of PI = 1.1. In the mortality analysis, the mean velocity was a risk factor for mortality (RR = 1.15). Conclusions: A high rate of intracranial hypertension was reported, with ONSD measurement being themost reliablemethod for estimation. The increase in ICP measured by ONSD in patients with severe COVID-19 on mechanical ventilation is not associated to hypercapnia or elevated intrathoracic pressures derived from protective mechanical ventilation. [ABSTRACT FROM AUTHOR]

Traditional methods of phylogenetic reconstruction and species delimitation may be impeded by frequent hybridization among lineages. In this study, we conducted phylogenetic and clustering analyses of ddRAD genomic data on the entire genus Salamandra, which includes six species and over 25 subspecies of terrestrial salamanders. We expanded previous datasets to include missing subspecies and incorporated new samples, with an emphasis on secondary contact zones. Results obtained from a full dataset of 392 individuals (356,874 bp; 24,192 SNPs) were compared with those obtained after excluding substantially admixed individuals (n = 95; 835,467 bp; 51,557 SNPs) to explore the consequences of introgression on phylogenetic inference and taxonomic arrangement of subspecies. We found conflicting phylogenetic placements for taxa represented by many admixed individuals (identified by clustering ancestries). In contrast, a time-calibrated tree constructed without hybrids largely agrees with previous phylogenetic hypotheses. Within S. atra, we found paraphyly of S. atra atra, suggesting an additional candidate subspecies. Within S. infraimmaculata, two lineages are assignable to known subspecies and we additionally identified a third, deeply diverged lineage sampled near the Turkish/Syrian border. In S. algira, we found limited admixture between the subspecies S. a. tingitana and S. a. splendens despite their geographic proximity. Finally, within S. salamandra, we detected significant levels of hybridization between subspecies, which blurred their phylogenetic relationships, although the removal of admixed samples in subset analyses clarified the situation in most cases. Monophyly was recovered for subspecies that were previously found paraphyletic, including S. s. salamandra, S. s. gallaica, and S. s. fastuosa. Salamandra s. "alfredschmidti" was confirmed to be a junior synonym of S. s. bernardezi. Previously disputed subspecies, like S. s. "molleri" and S. s. "hispanica", correspond to separated lineages but are affected by admixture with other lineages. Further newly identified candidate subspecies in S. salamandra included a southern lineage within S. s. wer-neri and a western lineage within S. s. bernardezi. Finally, we re-evaluate the status of recognized subspecies in Salamandra, based on evidence from multiple delimitation criteria. Given that the evolutionary history could not be resolved for all subspecies, we highlight taxa within Salamandra that warrant further molecular examination and taxonomic revision, notably within the S. s. gallaica/"molleri"/bejarae complex. This study illustrates the impact of hybridization in phylogenetic analyses and its downstream effects in the identification of conservation units and their naming in the Linnean classification. [ABSTRACT FROM AUTHOR]

Posterior reversible encephalopathy syndrome (PRES) is a rare neurological complication of allogeneic stem cell transplantation (incidence of 1.1-22%). Usually presents as a disorder of consciousness or encephalopathy, associated in most cases with headache, visual disturbance, Hypertension and epileptic seizures. Literature describes the presence of PRES in patients who have received immunosuppressive agents after Hematopoietic Stem Cells transplantation, including cyclosporine, tacrolimus, and sirolimus, as well as chemotherapy such as cyclophosphamide, vincristine, methotrexate, L-aspar, among others. Two cases of hematological patients with PRES are presented, and a review of the literature on PRES after Hematopoietic Stem Cells transplantation. [ABSTRACT FROM AUTHOR]

The area around the Malagasy village of Andasibe, which includes Analamazaotra-Mantadia National Park as well as other protected areas, is characterized by very species-rich and well-studied communities of animals and plants, but new species are still regularly discovered. Three species of phytotelmic frogs of the subgenus Pandanusicola in the genus Guibemantis are known from this area, G. flavobrunneus, G. liber, and G. pulcher. Further Pandanusicola frogs from this area have been provisionally assigned to G. bicalcaratus or G. albolineatus, pending detailed taxonomic review. During preliminary exploration of the ecology of these specialized frogs that live and reproduce in the leaf axils of Pandanus screw pines, we noticed the syntopic presence of two differently colored and differently sized Pandanusicola in Andasibe that could not be unambiguously assigned to any known species. A genetic screening revealed that these correspond to yet two further species in the area. Based on our data, seven species of Pandanusicola occur in Andasibe and nearby forests: (1) G. liber, the only non-phytotelmic species of the subgenus in the region; (2) G. flavobrunneus which is the largest species and characterized by a diagnostic yellowish brown dorsal pattern; (3) G. pulcher, characterized by translucent-green color with purplish brown spotting not observed in any other species in the area; (4) G. methueni, a brownish species usually lacking contrasted dorsolateral bands that differs from the other species in the area by emitting a characteristic trill-like advertisement call series (rather than clicks or chirps) and according to our data is widespread along Madagascars east coast; as well as three new species: (5) G. ambakoana sp. nov., a brownish species, typically with contrasted incomplete light dorsolateral bands and with single click-like advertisement calls; (6) G. vakoa sp. nov., a species that is equally brownish but lacks contrasted light dorsolateral bands and that has single click-like advertisement calls of very short duration; and (7) G. rianasoa sp. nov., a species that is smaller sized and has less distinct femoral glands than all the others, and emits a short series of soft chirp-like advertisement calls. All these species are genetically highly distinct, with >5% uncorrected pairwise distances in the mitochondrial 16S rRNA gene, and lack of haplotype sharing in two nuclear-encoded genes. The co-occurrence of seven Pandanusicola frogs in a relatively small geographic area is unprecedented in Madagascar and calls for in-depth studies of a possible differentiation in habitat use and life history.

Rapid biodiversity loss sets new requirements for taxonomic research, prompting updating some long-established practices to maximize timely documentation of species before they have gone extinct. One of the crucial procedures associated with the description of new taxa in Linnean taxonomy is assigning them a diagnosis, which is an account of the specific features of the taxon, differentiating it from already described species. Traditionally, diagnostic characters have been morphological, but especially in the case of morphologically cryptic species, molecular diagnoses become increasingly important. In this chapter, we provide detailed protocols for molecular taxon diagnosis with the bioinformatic tool MolD which is available as open-source Python code, command-line driven binary, GUI-driven executable for Windows and Mac, and Galaxy implementation. MolD identifies diagnostic combinations of nucleotides (DNCs) in addition to single (pure) diagnostic sites, enabling users to base DNA diagnoses on a minimal number of diagnostic sites necessary for reliable differentiation of taxa., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)