Anurans employ a wide variety of anti‐predator mechanisms to defend themselves. In casque‐headed hylids, defence is thought to be a complex combination of several anti‐predator mechanisms. However, ...the defence traits of only a few species are known; some hypotheses have yet to be addressed, whereas others, already tested in some species, need to be tested in additional taxa. The anti‐predator mechanism of the casque‐headed frog, Argenteohyla siemersi, is described here. It is a complex mechanism consisting of (1) behavioural and ecological traits, including secretive and semi‐phragmotic habits and posture; (2) morphological features, including cryptic and aposematic colourations, a skull covered with bony dermal spines and protuberances that are associated with two types of granular venom glands; and (3) physiological and chemical traits, such as a highly lethal skin secretion. Our results are compared with those of previous studies of defence mechanisms in casque‐headed frogs in an effort to understand the mechanisms and evaluate their potential phylogenetic signal in this group of anurans.
The complex anti‐predator mechanisms of the casque‐headed frog, Argenteohyla siemersi, are described, consisting of (1) behavioural and ecological traits, including secretive and semi‐phragmotic habits and posture; (2) morphological features, including cryptic and aposematic colourations, a skull covered with bony dermal spines and protuberances that are associated with two types of granular venom glands; and (3) physiological and chemical traits, such as a highly lethal skin secretion.
A Lochkovian (Early Devonian) ophiuroid (Echinodermata), Ophiocantabria elegans n. gen. and sp., is based on a single small, well-preserved specimen collected from a shale-rich horizon of the Furada ...Formation, Asturias, Spain. Sedimentologic and palaeontologic data suggest its occurrence was in a near-shore setting subjected to frequent storms. Ophiocantabria is assigned to the Encrinasteridae based on the morphology of individual skeletal elements, although overall form of the new species is similar to that of approximately coeval members of the asteroid family Xenasteridae. Such homoplasy, especially among earlier members of asterozoan class-level clades, is an important but not well understood aspect of subphylum evolution. KEYWORDS Ophiuroidea Echinodermata. Devonian. Spain. Phylogeny.
Accurate and timely prenatal diagnosis of spina bifida (SB) is a major goal of modern antenatal care. Prenatal screening for open SB should be first performed at the time of routine first-trimester ...ultrasound by examining the posterior fossa for obliteration or non-visualization of the fourth ventricle (“intracranial translucency”) and cisterna magna. The second step of screening is the second-trimester anatomy scan, at which time the features of the Chiari type II malformation should be looked for, including ventriculomegaly, scalloping of the frontal bones (“lemon” sign), and backward and caudal displacement of the cerebellar vermis with obliteration of the cisterna magna (“banana” sign). In cases with positive findings, evaluation must include a focused examination of the spine for defects. In cases of closed SB and SB occulta, the cranial and posterior fossa features will not be present as they are not associated with leaking of spinal fluid and resultant hindbrain herniation, highlighting the fact that the spine should be examined thoroughly whenever possible during the second-trimester scan. In tertiary fetal medicine centers, two-dimensional and three-dimensional ultrasound allows an accurate determination of the location, type, extent, and upper level of the spinal defect as well as the presence of associated anomalies. Fetal magnetic resonance imaging should be restricted to candidates for intrauterine surgery as part of the preoperative protocol.
The ability to correlate with high precision among geological successions is critical in evaluating the global coincidence and therefore magnitude and duration of geological events. This is a ...difficult problem given resolution uncertainties and ambiguities in biostratigraphic data sets. The magnetostratigraphy susceptibility (MSS) method, based on low-field bulk magnetic susceptibility (MS) measurements of closely spaced samples, provides a well-established, abiotic, high-resolution correlation tool in stratigraphy, that when combined with bio-, chemostratigraphic, and other geophysical techniques, offers ways to resolve correlation problems. In addition, such data sets lend themselves to time-series analysis, where developing high-resolution timing of events becomes possible. This paper examines the final episode (equivalent to the Geneseo Bioevent in the Appalachian Basin) of the important Taghanic Biocrisis known from globally distributed Middle Devonian geological sections. The Geneseo Bioevent is important because the extinction of some major fossil groups occurred during this time, while other groups declined significantly, including many benthonic groups. However, the maxima of extinctions does not appear to have occurred everywhere simultaneously. To help resolve timing of this bioevent, results are reported for two Middle Devonian successions from Northern Spain, the S. Huergas de Gordón and Punta Boletos sections, both showing the final Taghanic Biocrisis, Geneseo interval, and correlate these successions to the same interval within an independent, global database. Time-series analyses of the MSS data sets from the Spanish sections was performed using Multi-Taper (MTM) and Fourier Transform (FT) methods, and have extracted well-defined Milankovitch bands from the primary MS data from each section. Using FT and MTM values for eccentricity at ~
400
kyr and ~
100
kyr, a floating-point time scale was developed for the two Spanish sections that provides age resolution to ~
50
kyr for these successions. The results show that the Geneseo Bioevent in Northern Spain occurred within a narrow time window estimated to have lasted for ~
70
kyr. This time window fall
s within the
Polygnathus ansatus (uppermost part)–
Ozarkodina semialternans conodont zones, just at the Middle–Upper Givetian boundary of the Middle Devonian in what appears to be the upper, regressive phase of T–R cycle IIa.
► Well-defined Milankovitch bands from the primary magnetic susceptibility data. ► Timing of Taghanic Biocrisis, Geneseo Bioevent in mid-Devonian successions, Spain. ► S. Huergas de Gordón and Punta Boletos section examined and correlated. ► Time-series of Geneseo Bioevent estimates event lasted for ~
70
kyr. ► Timing falls within
Polygnathus ansatus–
Ozarkodina semialternans conodont Zone.
To review the prenatal complications, management, and perinatal outcome in pregnancies complicated by placental chorioangioma.
Cases of placental chorioangioma diagnosed prenatally as part of a ...prospective, multicentric program for fetal diagnosis and therapy were identified. All cases were evaluated with color flow imaging. In the latter part of the study, three-dimensional power Doppler angiography was also used to study the vascular pattern of the tumor. Information on maternal demographics, prenatal sonographic findings, pregnancy complications, antenatal intervention, and perinatal outcome was obtained by reviewing the medical records or contacting the referring obstetricians.
In the 5-year period from January 1997 to December 2001, 11 cases of placental chorioangioma were diagnosed prenatally. Nine cases were diagnosed in singleton and two in twin pregnancies. Among the nine cases occurring in singletons, five (56%) were associated with pregnancy complications, including polyhydramnios (
n = 3), oligohydramnios (
n = 2), fetal growth restriction (
n = 2), and nonimmune hydrops (
n = 1). Amniodrainage was required in one of these cases, allowing prolongation of pregnancy until term. Four (44%) singletons delivered before 35 weeks. Overall, two fetuses died, including one twin due to complications of twin–twin transfusion syndrome and another with hydrops after alcohol injection into the chorioangioma. In four pregnancies, no prenatal complications were detected in spite of continuous growth and vascularity of the placental mass in three of them.
Placental chorioangioma is associated with an increased risk of pregnancy complications, the most common being polyhydramnios and preterm delivery. In selected cases, amniodrainage allows continuation of the pregnancy with improving perinatal outcome. Fetuses who develop hydrops are at the highest risk for perinatal death, with limited therapeutic options being available. Close follow-up is advised, even in those cases with no associated findings at the time of the diagnosis.
Perhaps reflecting that children with COVID-19 rarely exhibit severe respiratory symptoms and often remain asymptomatic, little attention has been paid to explore the immune response in pediatric ...COVID-19. Here, we analyzed the phenotype and function of circulating neutrophils from children with COVID-19.
An observational study including 182 children with COVID-19, 21 children with multisystem inflammatory syndrome (MIS-C), and 40 healthy children was performed in Buenos Aires, Argentina. Neutrophil phenotype was analyzed by flow cytometry in blood samples. Cytokine production, plasma levels of IgG antibodies directed to the spike protein of SARS-CoV-2 and citrullinated histone H3 were measured by ELISA. Cell-free DNA was quantified by fluorometry.
Compared with healthy controls, neutrophils from children with COVID-19 showed a lower expression of CD11b, CD66b, and L-selectin but a higher expression of the activation markers HLA-DR, CD64 and PECAM-1 and the inhibitory receptors LAIR-1 and PD-L1. No differences in the production of cytokines and NETs were observed. Interestingly, the expression of CD64 in neutrophils and the serum concentration of IgG antibodies directed to the spike protein of SARS-CoV-2 distinguished asymptomatic from mild and moderate COVID-19.
Acute lung injury is a prominent feature of severe COVID-19 in adults. A low expression of adhesion molecules together with a high expression of inhibitory receptors in neutrophils from children with COVID-19 might prevent tissue infiltration by neutrophils preserving lung function.
This study was supported by the Ministry of Science and Technology (National Agency for Scientific and Technological Promotion, IP-COVID-19-0277 and PMO BID PICT 2018-2548), and University of Buenos Aires from Argentina (20020170100573BA).
García-Alcalde (1972) proposed the new genus Xana (type species Xana bubo García-Alcalde, 1972) for a terebratulid brachiopod included in the superfamily Stringocephalacea from the Lower Devonian of ...the Cantabrian Mountains (Northwestern Spain). In an email message sent on April 3, 2018, the entomologist Dr. Eduardo I. Faundez, from the Patagonia Institute, Magallanes University, Chile, warned the author that Xana was a name previously used by Kurdjumov (1917) for a hymenopteran genus. Xana García-Alcalde, 1972 would be so a later homonym of Xana Kurdjumov, 1917. In accordance with articles 52.3, 52.4, 53.2, 60.3 of the International Code of Zoological Nomenclature (ICZN) (2000), it is proposed here to replace the invalid name with the new name Xanastur.
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